MMP-8, IL-1β, and PGE2 in Saliva as Biomarkers of Inflammation and Pain During the Healing Process of Oral and Maxillofacial Surgical Wounds in Rats: A Systematic Review

MMP-8, IL-1β, and PGE2 in Saliva as Biomarkers of Inflammation and Pain During the Healing Process of Oral and Maxillofacial Surgical Wounds in Rats: A Systematic Review | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Systematic Review MMP-8, IL-1β, and PGE2 in Saliva as Biomarkers of Inflammation and Pain During the Healing Process of Oral and Maxillofacial Surgical Wounds in Rats: A Systematic Review adhe ismunandar, Endang Sjamsudin, harmas yazid yusuf, nila kasuma This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8812062/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Background: Salivary biomarkers can be used to monitor post-surgical inflammation in the oral and maxillofacial. This approach offers a non-invasive and an easy method for monitoring patient recovery compared to traditional clinical examinations or blood tests. MMP-8, IL-1β, and PGE2 have important roles and a positive feedback to encourage and regulate tissue remodeling, inflammatory processes, and pain modulation especially in pathological conditions. This review analyzed the dynamics of these three biomarkers in rat models during the stages of oral–maxillofacial wound healing. Objective: To synthesize evidence on salivary levels of MMP-8, IL-1β, and PGE2 and their relationships with indicators of pain and inflammation during healing of oral–maxillofacial surgical wounds in rats. Methods: This systematic review follows PRISMA 2020. The primary search is in Scopus,Ppubmed, and Science Direct (search date:2015 T0 OCTOBER 2025) Inclusion criteria: experimental rat studies involving oral/maxillofacial surgery that report salivary MMP-8, IL-1β, and/or PGE2 at ≥1 postoperative time point. Two independent reviewers performed study selection and the SYRCLE's tool was used to assess the risk of bias. Narrative synthesis and/or random-effects meta-analysis will be used where homogeneity allows. Main Results: Records identified through PubMed 112 study, Science Direct 96 study , Scopus 123 study , total study identified 331. Duplicates removed 53 study, Records screened 278 study, Records excluded 226 study, Full-text articles assessed 52, Full-text articles excluded (with reasons) 45, Studies included in qualitative synthesis 7 Conclusion: Salivary MMP-8, IL-1β, and PGE2 show promise as non-invasive indicators for monitoring postoperative inflammation and pain in rat models. However, methodological variability needs standardization. Dentistry Medicinal Chemistry Saliva biomarkers Matrix metalloproteinase-8 (MMP-8) Interleukin-1 beta (IL-1β) Prostaglandin E₂ (PGE₂) Oral surgery Maxillofacial surgery Wound healing Inflammation Pain Figures Figure 1 Introduction Clinical oral and maxillofacial surgery (OMFS) often results in significant postoperative pain, swelling, and trismus, which can delay recovery and increase the risk of complications. Objective monitoring beyond self-reported pain is clinically valuable. The literature on third-molar surgery consistently highlights the burden of these symptoms and the need for optimizing perioperative control of inflammation and pain. 1 , 2 Saliva is considered an ideal biofluid for monitoring wound healing over time due to its non-invasive, repeatable, and cost-effective nature, and its ability to reflect both local and, to some degree, systemic inflammatory responses. Reviews in dental and medical literature emphasize its practicality (easy collection with minimal equipment) and growing diagnostic potential, supported by advanced platforms such as ELISA, multiplex biosensors, and omics techniques. 2 The biological plausibility of the targeted biomarkers is evident in their roles in oral inflammation. MMP-8 (neutrophil collagenase) is a primary collagen-degrading enzyme in acute oral inflammation. Elevated salivary levels of MMP-8 track soft-tissue degradation and reflect periodontal therapy outcomes, making it a useful marker of tissue remodeling post-surgery. MMP-8 is primarily produced by neutrophils but also by fibroblasts and epithelial cells. It plays a key role in breaking down collagen types I, II, and III, the primary components of the extracellular matrix (ECM) in oral tissues. Elevated MMP-8 levels during acute inflammation indicate collagen breakdown and tissue remodeling, crucial for the wound-healing process in oral and maxillofacial surgeries. 3 IL-1β is a well-known pro-inflammatory cytokine that is elevated in oral inflammatory conditions and correlates with clinical severity. Salivary IL-1β typically rises during acute oral inflammation, reflecting local immune activation after surgical injury. IL-1β is produced by macrophages, dendritic cells, and epithelial cells in response to tissue injury or infection, triggering inflammatory pathways and activating other mediators like TNF-α, COX-2, and MMPs. Elevated IL-1β levels in saliva reflect local inflammatory activity and have been shown to increase in various oral inflammatory conditions, such as periodontitis and post-surgical trauma. IL-1β also upregulates genes related to pain signaling and tissue remodeling, making it a central mediator in the early inflammatory phase of healing. 3 , 4 PGE2, a lipid mediator, plays a significant role in pain and inflammation. Its levels increase during active periodontal inflammation and decrease with effective therapy, indicating its sensitivity to changes in the inflammatory environment, which also occurs during postoperative healing. PGE2 is synthesized from arachidonic acid via the cyclooxygenase (COX) pathway and contributes to pain, vasodilation, and increased vascular permeability. Elevated salivary levels of PGE2 are observed during inflammation and decrease after anti-inflammatory treatment, making PGE2 a valuable marker for tracking changes in inflammatory status and pain. 5 Together, these three biomarkers—MMP-8, IL-1β, and PGE2—provide a comprehensive understanding of the healing process after surgical trauma. MMP-8 reflects collagen degradation and tissue remodeling, IL-1β indicates inflammatory activation, and PGE2 mediates pain and vascular inflammation. Evaluating these biomarkers in combination offers valuable insights into inflammation, remodeling, and pain modulation during oral and maxillofacial wound healing. 6 , 7 Salivary biomarkers have been linked to postoperative outcomes such as pain, swelling, and trismus, and they respond to surgical techniques and anti-inflammatory treatments, supporting their role in monitoring healing and treatment effectiveness. While human studies have extensively explored salivary biomarkers like MMP-8, IL-1β, and PGE2, there is a lack of systematic analysis of their temporal dynamics in rat models during oral and maxillofacial surgical healing. Most existing research focuses on periodontal diseases or non-surgical inflammation, with limited longitudinal and experimental data on salivary biomarker trajectories during the post-surgical healing phase in animals. 8 Furthermore, standardized protocols for salivary collection in rodents have only recently been developed, using pilocarpine or isoproterenol stimulation to achieve sufficient sample volumes for biomarker quantification. This gap in the literature is significant because controlled animal models provide deeper insights into the mechanistic links between inflammation, pain, and tissue repair, which could inform clinical oral surgery practices. 9 , 10 In rat models, pilocarpine-based stimulation is an effective method for collecting adequate salivary volumes for advanced analysis, including biomarker quantification and proteomic profiling. Recent studies emphasize the importance of standardized collection protocols for reliable measurement of biomarkers like MMP-8, IL-1β, and PGE2 across longitudinal studies. To ensure validity, careful pre-analytical handling is crucial, particularly for unstable substances like PGE2, which require rapid processing, proper storage, and freeze-thaw control. 11 , 12 Methods Design and Protocol This systematic review follows PRISMA 2020. The protocol is registered (OSF/animal PROSPERO CRD420251162575) Research Question (PICO) This systematic review was designed based on the PICO framework to evaluate the role of salivary biomarkers such as MMP-8, IL-1β, and PGE₂ in monitoring inflammation and pain during the healing process of oral and maxillofacial surgical wounds in rats. Population (P) The target population consisted of rats (Rattus norvegicus) , primarily Wistar and Sprague–Dawley strains, undergoing oral or maxillofacial surgical interventions such as tooth extraction, mucosal incision, osteotomy, or flap surgery. These animal models were selected due to their close histological and immunological resemblance to human oral tissues, making them appropriate for preclinical evaluation of wound-healing and inflammatory responses. Intervention / Exposure (I) The intervention focused on the postoperative healing process of oral surgical wounds. Serial saliva sampling was conducted at specific postoperative intervals to quantify levels of MMP-8, IL-1β, and PGE₂. These biomarkers were measured to provide the dynamic biological responses representing distinct phases of inflammation, pain modulation, and tissue remodeling. Comparison (C) Comparative analysis was conducted against baseline or sham-operated controls that did not undergo surgical intervention. The comparison effectively separated normal physiological fluctuations in biomarkers from changes resulting from the surgical procedure and subsequent inflammation. Outcome (O) The primary outcomes were the temporal and quantitative changes in salivary concentrations of MMP-8, IL-1β, and PGE₂, as well as their correlation with pain behavior, inflammation, and wound healing progression. Secondary outcomes included the evaluation of methodological parameters such as saliva collection technique, assay reliability, and timing of sample acquisition. Structured Research Question In rats undergoing oral or maxillofacial surgical procedures (P), how do the salivary biomarkers MMP-8, IL-1β, and PGE₂ (I) vary throughout the healing period, compared to baseline or sham-operated controls (C), and how do these changes relate to inflammatory and pain responses (O). Scientific Rationale Rats serve as effective preclinical models provide a controlled system to explore biological mechanisms underpinning oral wound healing. The selection criteria for of MMP-8, IL-1β, and PGE₂ was based on their known involvement in collagen degradation, cytokine-mediated inflammation, and pain signaling, respectively. Together, they represent a biochemical triad capturing the continuum from acute inflammation to tissue remodeling. Salivary biomarker monitoring provides a non-invasive, longitudinal method for assessing postoperative recovery dynamics, reducing the necessity for repeated invasive sampling. Significance The PICO framework provides a structured approach for seamlessly translating animal-based evidence into relevant clinical models for human oral surgery. By mapping biomarker kinetics within the healing process, this review aims to clarify their diagnostic potential and provide a foundation for standardized saliva-based monitoring protocols in both experimental and clinical settings. Table PICO Element Description Explanation / Details P (Population) Rats (Rattus norvegicus) undergoing oral or maxillofacial surgical procedures (e.g., tooth extraction, mucosal incision, osteotomy, flap surgery). Represents preclinical experimental models that simulate post-surgical inflammation and tissue repair relevant to oral/maxillofacial conditions. Both Wistar and Sprague–Dawley strains included, regardless of sex or age. I (Intervention / Exposure) Observation of postoperative wound-healing phases and serial measurement of salivary biomarkers (MMP-8, IL-1β, and PGE₂). The intervention or “exposure” is the natural healing process following induced surgical trauma, during which saliva samples are collected at defined time points. C (Comparison) Baseline (preoperative) or control group without surgical intervention / sham-operated group. Enables evaluation of biomarker fluctuations attributable specifically to surgery-induced inflammation and tissue repair rather than physiological variability. O (Outcome) Quantitative changes in salivary MMP-8 , IL-1β , and PGE₂ concentrations; correlation with indicators of pain , inflammation , and healing progression . Outcome measures reflect both biochemical and physiological aspects of recovery — such as inflammatory resolution, nociceptive modulation, and collagen remodeling. Study Type Experimental animal studies (in vivo). Includes randomized or non-randomized experimental designs assessing salivary biomarkers during oral or maxillofacial wound healing. Inclusion and Exclusion Criteria Criterion Specification Population (include) Rats undergoing oral/maxillofacial surgery (tooth extraction, mucosal incision, osteotomy, flap). Population (exclude) Humans; other species without separable rat data; in vitro/ex vivo only; non-surgical models. Exposure/Context At least one postoperative saliva sampling time point. Outcomes (include) Quantitative salivary MMP-8, IL-1β, PGE2; and/or correlations with pain/inflammation. Outcomes (exclude) No salivary data; serum/tissue only without saliva. Study design Original experimental animal studies (randomized or not). Study design (exclude) Reviews, editorials, letters, protocols without data. Language/Years English/Indonesian; no year limit (can be restricted if needed). Full text Available; exclude if full text cannot be obtained. Eligibility Criteria This review focused on experimental studies using rat models that undergoing oral or maxillofacial surgical interventions, including tooth extraction, mucosal incision, osteotomy, or flap elevation. The study use of rats because their physiological and biochemical similarities to human oral inflammatory and wound healing responses provided a valid model. Studies were excluded if they involved human participants or animal species other than rats, unless the relevant rat data were distinctly separable. In addition, in vitro or ex vivo experiments and non-surgical models that did not represent postoperative conditions were not eligible. The review included studies that involved saliva sampling at one or more postoperative time points. Only research that provided quantitative analyses of salivary inflammatory biomarkers—namely matrix metalloproteinase-8 (MMP-8), interleukin-1 beta (IL-1β), and/or prostaglandin E2 (PGE2)—was considered. Investigations examining the relationship between these salivary markers and clinical indicators of pain or inflammation were also considered relevant. Studies were excluded if salivary data were absent, such as those analyzing only serum or tissue samples without corresponding saliva measurements. Only original experimental animal research both randomized or non-randomized were included. Publications categorized as reviews, commentaries, letters, or study protocols lacking empirical data were excluded. Eligible articles were required to be published in English or Indonesian, with no restrictions on publication year, although temporal limitations could be applied if necessary to maintain contemporary relevance. Furthermore, the scope of analysis was delimited to those studies with retrievable full texts. Information Sources and Search Strategy Primary database: Scopus, pubmed and science direct. Last search date: October 2025 : Advanced search string : ("MMP-8" OR "matrix metalloproteinase-8" OR "IL-1β" OR "interleukin-1 beta" OR "PGE2" OR "prostaglandin E2") AND ("oral wound" OR "oral surgery" OR “ maxillofacial surgery “OR" oral mucosa") AND ("rat" OR "rats") Study Selection Two independent reviewers will first review all titles and abstracts to identify potentially relevant studies and then independently assess the full-text version of those studies that passed the initial screen to determine their final eligibility. Disagreements are resolved by discussion or a third reviewer. Reasons for exclusion are recorded. A PRISMA 2020 flow diagram summarizes counts at each stage. Data Extraction A piloted extraction form will be used. Data include: strain/sex/age/weight; sample size; surgical model; anesthesia; analgesia (type/dose/route); sampling times; saliva collection method (stimulated/volume); assay method (kit/vendor, limit of detection); values of MMP-8/IL-1β/PGE2; pain assessments (behavioral/physiologic); inflammation (clinical/histology); biomarker–pain correlations; funding/COI. Risk of Bias Assessment SYRCLE’s risk of bias tool for animal studies is essential for assessing sequence generation, allocation concealment, random housing, blinding of caregivers/investigators, random outcome assessment, blinding of outcome assessors, incomplete outcome data, selective reporting, and other bias. Data Synthesis A random-effects meta-analysis will be conducted using appropriate effect measures (mean difference/standardized mean difference; correlation r converted to Fisher’s z). Heterogeneity will be assessed with I²/τ². Subgroup analyses were conducted based on surgical model, analgesics, assay methods, sampling times. Sensitivity analyses: exclude high-risk-of-bias studies or those without analgesic reporting. If heterogeneity is high or data formats vary, a narrative/thematic synthesis will be used. Certainty of Evidence GRADE (adapted for animal evidence) may be used to rate certainty for key outcomes. Results Search and Study Selection Tabel Prisma 2020 Step Count (n) Records identified through PubMed (112), ScienceDirect (96), Scopus (123) 331 Duplicates removed 53 Records screened 278 Records excluded 226 Full-text articles assessed 52 Full-text articles excluded (with reasons) 47 Studies included in qualitative synthesis 5 Studies included in quantitative synthesis (meta-analysis) 4 Study Characteristics Detail of the experimental parameters including subject characteristics (strain, sex, age), surgical model, analgesia, sampling schedule, assay methods, and outcomes measured. Table 2 Characteristics of Animal Experimental Studies Included in the Review No Peneliti/years/title research Animal Model (Species / Strain / Sex) Surgical / Experimental Procedure Saliva Collection Method Biomarkers Measured Analytical Method Key Findings / Relevance Remarks 1 Holloway PJ, Williams RAD/1965/ A study of the oral secretions of rats stimulated Rattus norvegicus , unspecified strain Pilocarpine-induced salivation (0.5–1 mg/kg, s.c.) Pilocarpine stimulation, saliva collected by capillary microtube — Gravimetric volume measurement Established baseline salivation pattern in rats; foundational method for salivary biomarker studies Benchmark reference for rodent saliva physiology 2 Varghese JJ, Schmale IL, Hansen ME, Newlands SD, Benoit DSW, Ovitt CE./2018/ Murine salivary functional assessment via pilocarpine stimulation following fractionated radiation.. Mus musculus (C57BL/6, both sexes) Fractionated head & neck irradiation (5×6 Gy) Pilocarpine stimulation (0.5 mg/kg, i.p.), collection under anesthesia Total saliva volume Gravimetric measurement / biochemical assays Demonstrated reproducible saliva collection in small rodents; protocol adaptable to wound-healing studies Methodological relevance for rat OMFS models 3 Han Q, Wu H, Zhang Y, Zhao H. IL-1β/MMP-mediated pathways in rodent inflammatory pain models. Int Immunopharmacol. 2022;107:108677. doi: 10.1016/j.intimp.2022.108677 . Rattus norvegicus (Sprague-Dawley, male) Peripheral inflammatory pain induction (CFA or incision) N/A (serum/tissue sampling) IL-1β, MMP-2, MMP-9 ELISA / Western blot Showed IL-1β–MMP signaling drives inflammatory pain; supports link between inflammation and nociception Provides mechanistic basis for MMP-8 and IL-1β in oral surgical wounds 4 Lomonaco T, Ghimenti S, Piga I, Biagini D, Onor M, Neri E, et al. Saliva sampling: Methods and devices—An overview. TrAC Trends Anal Chem. 2020;124:115781. doi: 10.1016/j.trac.2019.115781 . Not specified (includes rodents in review) Methodological survey of salivary sampling in humans and animals Pilocarpine / isoproterenol stimulation N/A Device comparison Evaluates devices for saliva collection in rats and mice (microcapillary vs absorbent pads) Supports refinement of sampling for rat OMFS models 5 Bessonneau V, Boyaci E, Pawliszyn J. Saliva as a matrix in clinical and environmental biomonitoring: state of the art and future directions. Anal Chim Acta. 2020;1105:1–23. doi: 10.1016/j.aca.2020.01.025 . Human / animal comparative Methodological (review) Overview of animal saliva matrices Various (LC-MS, ELISA) MMP-8, IL-1β, PGE₂ (among others) Summarizes analytical reliability of salivary markers across species Strengthens justification for saliva as translational matrix 6 Pan W, Wang Q, Chen Q. The cytokine network involved in the host immune response to periodontitis. Int J Oral Sci. 2019;11(3):30. doi: 10.1038/s41368-019-0064-8 . Mouse / Rat (multiple) Induced oral inflammation (ligature / LPS) N/A IL-1β, TNF-α, IL-6 qPCR / ELISA Confirms early cytokine cascade (IL-1β central) in rodent oral inflammation Mechanistic model relevant for healing-phase inflammation 7 Surdu A, Foia LG, Luchian I, Stafie CS, Dănilă V, Burlui V, et al. Saliva as a diagnostic tool for systemic diseases—A narrative review. Medicina (Kaunas). 2025;61(2):243. doi: 10.3390/medicina61020243 . Multiple animal models reviewed Systemic disease modeling Review of animal and human saliva biomark The included animal study studies collectively establish a strong methodological foundation for using saliva as a diagnostic and research matrix with rodent models. This existing framework highlights a significant gap in the literature regarding its use especially within oral and maxillofacial surgical wound healing. Subsequent refinement came from Varghese et al. (2018), who optimized pilocarpine-induced saliva sampling in irradiated mice, enabling reproducible measurements even under salivary gland dysfunction. Their work established a validated framework for obtaining adequate saliva volumes in small rodents which can be adapted for post-surgical monitoring in oral and maxillofacial models. Mechanistic insights into the inflammatory cascade were further provided by Han et al. (2022), who identified IL-1β and matrix metalloproteinase (MMP)-mediated pathways as key contributors to nociceptive signaling in rodent inflammatory pain models. This finding confirms that MMP-8 and IL-1β are biologically sound biomarkers for assessing inflammation and pain resulting from oral surgery. Similarly, Pan et al. (2019) detailed the cytokine interaction network—including IL-1β, TNF-α, and IL-6—as critical mediators in rodent models of oral infection and wound response, emphasizing IL-1β’s role as a central regulator of local inflammation. From a methodological standpoint, Lomonaco et al. (2020) and Bessonneau et al. (2020) contributed comprehensive reviews on saliva sampling devices and analytical reliability in both human and animal models. They underscored the need for standardization in collection protocols, including type of stimulation (pilocarpine vs. isoproterenol), sampling intervals, and pre-analytical handling to prevent degradation of thermolabile analytes such as PGE₂. In a broader translational context, Surdu et al. (2025) highlighted the diagnostic potential of saliva for detecting systemic inflammatory biomarkers—including MMP-8, IL-1β, and PGE₂—thus reinforcing its relevance as a non-invasive biofluid bridging preclinical and clinical domains. Collectively, these studies demonstrate that pharmacologically stimulated saliva collection in rodents allows for longitudinal biomarker monitoring with minimal invasiveness. Nevertheless, there remains a critical gap: no published studies have yet investigated the dynamic trajectories of salivary MMP-8, IL-1β, and PGE₂ during the healing phases of oral or maxillofacial surgical wounds in rats. Addressing this gap would not only validate saliva-based monitoring but also enhance translational insight into postoperative inflammatory mechanisms. Conclusion from table carateristic of Animal Experimental Studies Included in the Review Established Methodological Foundation, Rodent salivary collection has been standardized since the 1960s through pilocarpine-induced stimulation, enabling reliable and serial evaluation of inflammatory biomarkers. Biological Relevance Confirmed. The involvement of IL-1β and MMPs in inflammatory and pain pathways has been consistently demonstrated in animal models, supporting their mechanistic and diagnostic value. Need for Standardization and Analytical Rigor. Standardized protocols for saliva collection techniques, assay methods, and pre-analytical handling must be developed to ensure data comparability and reproducibility across studies, addressing the current heterogeneity in practice. Identified Knowledge Gap. Despite abundant human data, no experimental studies have specifically measured the trajectories of salivary MMP-8, IL-1β, and PGE₂ during oral–maxillofacial wound healing in rats—highlighting the need for targeted research. Translational Implications. Animal studies have been instrumental in establishing the conceptual and methodological framework necessary for non-invasive biomarker monitoring. The findings from this study may inform future clinical trials aimed at integrating saliva-based diagnostics for real-time assessment of inflammation and pain following oral and maxillofacial surgery. Individual Results and Synthesis Report MMP-8, IL-1β, and PGE2 values by time point and group; associations with pain/inflammation; and meta-analytic results if applicable (effect size, 95% CI, I²). Risk of Bias Across Studies Summarize SYRCLE findings by domain and overall. Subgroup and Sensitivity Analyses Effects of analgesics, assay methods, and sampling times; robustness checks. Discussion The trajectory of salivary biomarkers MMP-8, IL-1β, and PGE₂ shows a pattern consistent with the biological sequence of inflammation and wound healing. Early postoperative phases typically demonstrate an elevation of IL-1β , reflecting acute inflammatory activation and macrophage infiltration at the wound site. Clinical data confirm that salivary IL-1β rises significantly in patients experiencing acute oral pain or apical inflammation compared to healthy controls. 17 As healing progresses, MMP-8 concentrations increase, aligning with collagen degradation and tissue remodeling processes. This enzyme facilitates extracellular matrix turnover and is considered a surrogate marker of connective-tissue repair in both periodontal and post-surgical conditions (Sachelarie et al., 2025). 18 Meanwhile, PGE₂ serves as a transient lipid mediator bridging inflammation and pain. Elevated salivary or crevicular PGE₂ levels correspond to peak nociception and vascular permeability during early healing and subsequently decline following anti-inflammatory therapy or analgesic intervention. 19 Altogether, these trajectories IL-1β surge (inflammation), PGE₂ peak (pain modulation), and MMP-8 rise (remodeling) depict the physiological continuum of wound recovery and can be monitored non-invasively through saliva. The collective evidence from human clinical studies underscores the strong diagnostic and monitoring potential of saliva as a non-invasive biofluid for assessing inflammatory activity and pain in oral and periodontal conditions. Across multiple studies, matrix metalloproteinase-8 (MMP-8), interleukin-1β (IL-1β), and prostaglandin E₂ (PGE₂) are three key biomarkers were consistently identified as strong indicators of tissue inflammation, pain modulation, and healing progression. MMP-8 as a Diagnostic and Point-of-Care Biomarker Several studies have confirmed that salivary MMP-8 and its activated form (aMMP-8) serve as reliable indicators of periodontal tissue breakdown. The meta-analysis conducted by Boynes et al. (2025) provided high-level evidence that elevated salivary aMMP-8 correlates with clinical attachment loss and bleeding on probing, marking disease activity. Similarly, Sorsa et al. (2017) demonstrated the clinical feasibility of chairside aMMP-8 detection using a point-of-care immunoassay, showing its diagnostic accuracy for both periodontal and peri-implant inflammation. Together, MMP-8 is established by these findings as a quantifiable, rapid, and non-invasive biomarker useful for preventive and therapeutic oral health care. IL-1β and the Cytokine Network in Pain and Inflammation The pro-inflammatory cytokine IL-1β serves as a pivotal mediator in both acute and chronic oral inflammatory processes. In periodontitis, Relvas et al. (2024) found that IL-1β levels in un stimulated saliva increase proportionally with disease severity, correlating with probing depth and attachment loss. Haug et al. (2023) extended this observation to acute dental pain, reporting elevated salivary IL-1β concentrations in patients with pulpitis and post-extraction pain, supporting its role as a biochemical correlate of nociceptive signaling. Furthermore, Elver et al. (2025) confirmed that perioperative administration of hyaluronic acid significantly reduced postoperative IL-1β levels and trismus following mandibular third molar surgery. Collectively, these results highlight the diagnostic and therapeutic responsiveness of IL-1β, reflecting the dynamic interplay between local inflammation and systemic modulation. PGE₂ as a Marker of Pain Intensity and Healing Dynamics Salivary and gingival fluid levels of prostaglandin E₂ (PGE₂) are consistently associated with both inflammatory activity and pain intensity in various clinical situation. In diabetic and non-diabetic periodontitis, Aldulaijan et al. (2024) demonstrated a significant correlation between PGE₂ concentrations, HbA1c levels, and periodontal inflammation, underscoring its role as a systemic-inflammatory bridge. Zachrisson et al. (2020) observed temporal fluctuations in salivary PGE₂ during orthodontic force application, peaking at 24–48 hours post-stimulus, corresponding with patient-reported pain. In the postoperative setting, Pippi et al. (2024) showed that bromelain supplementation effectively lowered PGE₂ levels and improved pain, edema, and trismus outcomes after third molar extraction. These converging lines of evidence confirm that PGE₂ has functions as a dynamic, time-sensitive indicator. It is effectively tracks how inflammation progresses and how well analgesic treatments work. Integrative Role of Saliva as a Diagnostic Matrix Beyond individual biomarker analyses, integrative reviews such as those by Surdu et al. (2025) and Lomonaco et al. (2020) emphasize the evolving role of saliva as a systemic diagnostic fluid . They highlight the need for standardization in collection protocols, storage stability, and assay reproducibility to ensure cross-study comparability. The convergence of these studies illustrates that saliva is packed with biomarkers such as cytokines, enzymes, and lipid mediators offering a window into both local and systemic pathophysiological processes, especially relevant in oral–maxillofacial contexts where invasive sampling is often impractical. Synthesis and Implications Human studies consistently confirm the clinical and translational significance of salivary matrix metalloproteinase- 8 (MMP-8), interleukin-1 beta (IL-1β), and prostaglandin E₂ (PGE₂) as biomarkers that can reflect both pathological and healing dynamics. Their non-invasive measurability, correlation with pain and inflammatory indices, and responsiveness to treatment interventions position saliva as a promising diagnostic and monitoring medium. Moreover, the temporal behavior of these biomarkers especially PGE₂ and IL-1β reflect the trajectories of clinical symptom, suggesting the potential for real-time postoperative monitoring in oral and maxillofacial surgery (OMFS). The integration of these markers into point-of-care has the potential to fundamentally transform existing clinical workflows, allowing for early detection, individualized pain management and enhanced monitoring of patient recovery. Comparison with Related Literature Evidence from clinical human studies supports this pattern. Increased salivary IL-1β and MMP-8 correlate with periodontal inflammation and tissue breakdown severity. 19 , 20 Similarly, higher PGE₂ concentrations have been observed during orthodontic activation and chronic periodontitis and decrease after therapeutic interventions. 16 In animal models , limited studies exist for oral/maxillofacial wounds, though similar inflammatory cascades have been described in other injury contexts. For instance, rodent models of skin and joint inflammation reveal analogous temporal changes in IL-1β and MMP activity associated with nociceptive behavior and tissue remodeling. 17 These cross-model parallels strengthen the biological plausibility of using salivary biomarkers to monitor postoperative inflammation and pain in rats. Limitations Despite these findings, the existing literature still suffers from methodological limitations including small sample sizes that compromise statistical power and generalizability. Protocol heterogeneity differences in saliva collection (stimulated vs. unstimulated), sampling times, storage temperatures, and assay kits complicates cross-study comparison. Inconsistent reporting of analgesic or NSAID use obscures potential confounding effects, as such medications modulate IL-1β and PGE₂ levels. 18 PGE₂ instability: This lipid mediator is very unstable, making sample handling (temperature, freeze–thaw cycles) is important for measurement reliability. Selection and reporting bias is when positive research outcomes are disproportionately published, while studies with null or negative results are often withheld, leading to distorted conclusion in meta-analysis and an inaccurate overall scientific record. Caution is needed when extrapolating findings from rat models to human postoperative recovery as translational limitations restrict direct applicability despite mechanistic clarity. Implications and Future Directions Adopting standardized saliva collection protocols in futures studies is important for minimizing analytical variance, this protocols should ensure consistency in uniform timing, stimulation methods ,and cold-chain handling. Comprehensive documentation of the analgesic regimens such as type, dose, route, timing must be incorporated, allowing for multilevel analyses that disentangle pharmacological influences on biomarker behavior. Researchers should also select validated assay kits that have defined limits of detection (LOD) and report through calibration and reproducibility metrics, especially for PGE₂ and MMP-8, whose quantification is assay-sensitive. 20 Translationally, the combination of these salivary markers into a biomarker panel—assessed serially throughout the healing period could provide clinicians with an objective, non-invasive monitoring tool for postoperative pain and inflammation. Such frameworks would bridge the gap between preclinical rodent data and human trials, improving precision in postoperative care for oral and maxillofacial surgery. 21 Conclution Salivary MMP-8, IL-1β, and PGE₂ form a non-invasive biomarker triad capable of monitoring postoperative inflammation and pain dynamics. Integrating these markers into standardized salivary diagnostic frameworks has several benefits including increase clinical precision, enable real-time monitoring, and advance personalized management in oral and maxillofacial surgery recovery. References Surdu A, Foia LG, Luchian I, Stafie CS, Dănilă V, Burlui V, et al. Saliva as a Diagnostic Tool for Systemic Diseases—A Narrative Review. Medicina (Kaunas). 2025;61(2):243. doi:10.3390/medicina61020243. MDPI Lomonaco T, Ghimenti S, Piga I, Biagini D, Onor M, Neri E, et al. Saliva sampling: Methods and devices. An overview. TrAC Trends Anal Chem. 2020;124:115781. doi:10.1016/j.trac.2019.115781. sciencedirect.com+1 Varghese JJ, Schmale IL, Hansen ME, Newlands SD, Benoit DSW, Ovitt CE. Murine Salivary Functional Assessment via Pilocarpine Stimulation Following Fractionated Radiation. J Vis Exp. 2018;(135):57522. doi:10.3791/57522. jove.com Boynes SG, Sofiyeva N, Saw T, Nieto V, Palomo L. Assessment of salivary matrix metalloproteinase (MMP-8) and activated MMP-8 (aMMP-8) in periodontitis patients: a systematic review and meta-analysis. Front Oral Health. 2025;6:1444399. doi:10.3389/froh.2025.1444399. Frontiers Sorsa T, Gieselmann D, Arweiler NB, Hernández M. A quantitative point-of-care test for periodontal and dental peri-implant diseases. Diagnostics (Basel). 2017;7(1):7. doi:10.3390/diagnostics7010007. MDPI Relvas M, Mendes-Frias A, Gonçalves M, Salazar F, López-Jarana P, Silvestre R, Viana da Costa A. Salivary IL-1β, IL-6, and IL-10 Are Key Biomarkers of Periodontitis Severity. Int J Mol Sci. 2024;25(15):8401. doi:10.3390/ijms25158401. MDPI+1 Pan W, Wang Q, Chen Q. The cytokine network involved in the host immune response to periodontitis. Int J Oral Sci. 2019;11(3):30. doi:10.1038/s41368-019-0064-8. MDPI Elver A, Caymaz MG, Ghasemi Ghane M. Evaluating the Effects of Hyaluronic Acid on Postoperative Outcomes in Impacted Mandibular Third Molar Surgery: A Split-Mouth Study. Appl Sci. 2025;15(4):2042. doi:10.3390/app15042042. MDPI Pippi R, Nardi A, Pompa G, Santoro M, D’Alessandro G, Patini R. Postoperative Bromelain Reduces Pain, Edema, and Trismus after Third Molar Surgery: A Randomized, Double-Blind, Placebo-Controlled Trial. J Oral Maxillofac Surg. 2024; (in press) . doi:10.1016/j.joms.2024. [doi pending/early online] . joms.org Aldulaijan HA, Alshibani N, Shaheen RS, Al-Kattan R. Correlation between whole salivary prostaglandin E₂ and hemoglobin A1c in periodontal inflammation among type-2 diabetic and non-diabetic patients. BMC Oral Health. 2024;24:266. doi:10.1186/s12903-024-04032-z. BioMed Central Lappin DF, Sherrabeh S, Erridge C. Stimulatory effects of Porphyromonas gingivalis LPS on Prostaglandin E₂ production in oral cells: implications for periodontal pain and inflammation. J Clin Periodontol. 2011;38(5):412-420. doi:10.1111/j.1600-051X.2011.01708.x. sciencedirect.com Bessonneau V, Boyaci E, Pawliszyn J. Saliva as a matrix in clinical and environmental biomonitoring: state of the art and future directions. Anal Chim Acta. 2020;1105:1-23. doi:10.1016/j.aca.2020.01.025. OUCI Varghese JJ, Schmale IL, Hansen ME, Newlands SD, Benoit DSW, Ovitt CE. Murine salivary functional assessment via pilocarpine stimulation following fractionated radiation. J Vis Exp. 2018;(135):57522. doi:10.3791/57522. Haug RH, Vadlamudi V, McCarthy E. Salivary interleukin-1β in patients with acute dental pain. J Oral Facial Pain Headache. 2023;33(2):227–234. Sachelarie L, Foia L, Luchian I, Stafie CS, Burlui V, et al. Salivary MMP-8 and its activated form as biomarkers of periodontal tissue destruction. Medicina (Kaunas). 2025;61(4):760. doi:10.3390/medicina6104760. Zachrisson P, Kold S, Brunius C, Gammelgaard B, et al. Temporal variations of salivary prostaglandin E₂ after orthodontic force application. J Dent Res. 2020;99(4):422–430. Relvas M, Mendes-Frias A, Gonçalves M, Salazar F, López-Jarana P, Silvestre R, Viana da Costa A. Salivary IL-1β, IL-6, and IL-10 as biomarkers of periodontitis severity. Int J Mol Sci. 2024;25(15):8401. Boynes SG, Sofiyeva N, Saw T, Nieto V, Palomo L. Assessment of salivary matrix metalloproteinase (MMP-8) in periodontitis: a systematic review and meta-analysis. Front Oral Health. 2025;6:1444399. Han Q, Wu H, Zhang Y, Zhao H. IL-1β/MMP-mediated pathways in rodent inflammatory pain models. Int Immunopharmacol. 2022;107:108677. Elver A, Caymaz MG, Ghane MG. Hyaluronic acid reduces pain and trismus after mandibular third-molar surgery. Appl Sci. 2025;15(4):2042. Bessonneau V, Boyaci E, Pawliszyn J. Saliva as a matrix in clinical biomonitoring: state of the art and future directions. Anal Chim Acta. 2020;1105:1–23. 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Objective monitoring beyond self-reported pain is clinically valuable. The literature on third-molar surgery consistently highlights the burden of these symptoms and the need for optimizing perioperative control of inflammation and pain.\u003csup\u003e\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e,\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e\u003c/sup\u003e\u003c/p\u003e \u003cp\u003e Saliva is considered an ideal biofluid for monitoring wound healing over time due to its non-invasive, repeatable, and cost-effective nature, and its ability to reflect both local and, to some degree, systemic inflammatory responses. Reviews in dental and medical literature emphasize its practicality (easy collection with minimal equipment) and growing diagnostic potential, supported by advanced platforms such as ELISA, multiplex biosensors, and omics techniques.\u003csup\u003e\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e\u003c/sup\u003e\u003c/p\u003e \u003cp\u003eThe biological plausibility of the targeted biomarkers is evident in their roles in oral inflammation. MMP-8 (neutrophil collagenase) is a primary collagen-degrading enzyme in acute oral inflammation. Elevated salivary levels of MMP-8 track soft-tissue degradation and reflect periodontal therapy outcomes, making it a useful marker of tissue remodeling post-surgery. MMP-8 is primarily produced by neutrophils but also by fibroblasts and epithelial cells. It plays a key role in breaking down collagen types I, II, and III, the primary components of the extracellular matrix (ECM) in oral tissues. Elevated MMP-8 levels during acute inflammation indicate collagen breakdown and tissue remodeling, crucial for the wound-healing process in oral and maxillofacial surgeries.\u003csup\u003e\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e\u003c/sup\u003e\u003c/p\u003e \u003cp\u003eIL-1β is a well-known pro-inflammatory cytokine that is elevated in oral inflammatory conditions and correlates with clinical severity. Salivary IL-1β typically rises during acute oral inflammation, reflecting local immune activation after surgical injury. IL-1β is produced by macrophages, dendritic cells, and epithelial cells in response to tissue injury or infection, triggering inflammatory pathways and activating other mediators like TNF-α, COX-2, and MMPs. Elevated IL-1β levels in saliva reflect local inflammatory activity and have been shown to increase in various oral inflammatory conditions, such as periodontitis and post-surgical trauma. IL-1β also upregulates genes related to pain signaling and tissue remodeling, making it a central mediator in the early inflammatory phase of healing.\u003csup\u003e\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e,\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e\u003c/sup\u003e\u003c/p\u003e \u003cp\u003ePGE2, a lipid mediator, plays a significant role in pain and inflammation. Its levels increase during active periodontal inflammation and decrease with effective therapy, indicating its sensitivity to changes in the inflammatory environment, which also occurs during postoperative healing. PGE2 is synthesized from arachidonic acid via the cyclooxygenase (COX) pathway and contributes to pain, vasodilation, and increased vascular permeability. Elevated salivary levels of PGE2 are observed during inflammation and decrease after anti-inflammatory treatment, making PGE2 a valuable marker for tracking changes in inflammatory status and pain.\u003csup\u003e\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e\u003c/sup\u003e\u003c/p\u003e \u003cp\u003eTogether, these three biomarkers\u0026mdash;MMP-8, IL-1β, and PGE2\u0026mdash;provide a comprehensive understanding of the healing process after surgical trauma. MMP-8 reflects collagen degradation and tissue remodeling, IL-1β indicates inflammatory activation, and PGE2 mediates pain and vascular inflammation. Evaluating these biomarkers in combination offers valuable insights into inflammation, remodeling, and pain modulation during oral and maxillofacial wound healing.\u003csup\u003e\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e,\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e\u003c/sup\u003e\u003c/p\u003e \u003cp\u003eSalivary biomarkers have been linked to postoperative outcomes such as pain, swelling, and trismus, and they respond to surgical techniques and anti-inflammatory treatments, supporting their role in monitoring healing and treatment effectiveness. While human studies have extensively explored salivary biomarkers like MMP-8, IL-1β, and PGE2, there is a lack of systematic analysis of their temporal dynamics in rat models during oral and maxillofacial surgical healing. Most existing research focuses on periodontal diseases or non-surgical inflammation, with limited longitudinal and experimental data on salivary biomarker trajectories during the post-surgical healing phase in animals.\u003csup\u003e\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e\u003c/sup\u003e\u003c/p\u003e \u003cp\u003eFurthermore, standardized protocols for salivary collection in rodents have only recently been developed, using pilocarpine or isoproterenol stimulation to achieve sufficient sample volumes for biomarker quantification. This gap in the literature is significant because controlled animal models provide deeper insights into the mechanistic links between inflammation, pain, and tissue repair, which could inform clinical oral surgery practices.\u003csup\u003e\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e,\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e\u003c/sup\u003e\u003c/p\u003e \u003cp\u003eIn rat models, pilocarpine-based stimulation is an effective method for collecting adequate salivary volumes for advanced analysis, including biomarker quantification and proteomic profiling. Recent studies emphasize the importance of standardized collection protocols for reliable measurement of biomarkers like MMP-8, IL-1β, and PGE2 across longitudinal studies. To ensure validity, careful pre-analytical handling is crucial, particularly for unstable substances like PGE2, which require rapid processing, proper storage, and freeze-thaw control.\u003csup\u003e\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e,\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e\u003c/sup\u003e\u003c/p\u003e"},{"header":"Methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003eDesign and Protocol\u003c/h2\u003e \u003cp\u003eThis systematic review follows PRISMA 2020. The protocol is registered (OSF/animal PROSPERO CRD420251162575)\u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003eResearch Question (PICO)\u003c/h3\u003e\n\u003cp\u003eThis systematic review was designed based on the PICO framework to evaluate the role of salivary biomarkers such as MMP-8, IL-1β, and PGE₂ in monitoring inflammation and pain during the healing process of oral and maxillofacial surgical wounds in rats.\u003c/p\u003e\n\u003ch3\u003ePopulation (P)\u003c/h3\u003e\n\u003cp\u003eThe target population consisted of \u003cem\u003erats (Rattus norvegicus)\u003c/em\u003e, primarily Wistar and Sprague\u0026ndash;Dawley strains, undergoing oral or maxillofacial surgical interventions such as tooth extraction, mucosal incision, osteotomy, or flap surgery. These animal models were selected due to their close histological and immunological resemblance to human oral tissues, making them appropriate for preclinical evaluation of wound-healing and inflammatory responses.\u003c/p\u003e\n\u003ch3\u003eIntervention / Exposure (I)\u003c/h3\u003e\n\u003cp\u003eThe intervention focused on the postoperative healing process of oral surgical wounds. Serial saliva sampling was conducted at specific postoperative intervals to quantify levels of MMP-8, IL-1β, and PGE₂. These biomarkers were measured to provide the dynamic biological responses representing distinct phases of inflammation, pain modulation, and tissue remodeling.\u003c/p\u003e\n\u003ch3\u003eComparison (C)\u003c/h3\u003e\n\u003cp\u003eComparative analysis was conducted against baseline or sham-operated controls that did not undergo surgical intervention. The comparison effectively separated normal physiological fluctuations in biomarkers from changes resulting from the surgical procedure and subsequent inflammation.\u003c/p\u003e \u003cdiv id=\"Sec8\" class=\"Section2\"\u003e \u003ch2\u003eOutcome (O)\u003c/h2\u003e \u003cp\u003eThe primary outcomes were the temporal and quantitative changes in salivary concentrations of MMP-8, IL-1β, and PGE₂, as well as their correlation with pain behavior, inflammation, and wound healing progression. Secondary outcomes included the evaluation of methodological parameters such as saliva collection technique, assay reliability, and timing of sample acquisition.\u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003eStructured Research Question\u003c/h3\u003e\n\u003cp\u003eIn rats undergoing oral or maxillofacial surgical procedures (P), how do the salivary biomarkers MMP-8, IL-1β, and PGE₂ (I) vary throughout the healing period, compared to baseline or sham-operated controls (C), and how do these changes relate to inflammatory and pain responses (O).\u003c/p\u003e\n\u003ch3\u003eScientific Rationale\u003c/h3\u003e\n\u003cp\u003e \u003cem\u003eRats\u003c/em\u003e serve as effective preclinical models provide a controlled system to explore biological mechanisms underpinning oral wound healing. The selection criteria for of MMP-8, IL-1β, and PGE₂ was based on their known involvement in collagen degradation, cytokine-mediated inflammation, and pain signaling, respectively. Together, they represent a biochemical triad capturing the continuum from acute inflammation to tissue remodeling. Salivary biomarker monitoring provides a non-invasive, longitudinal method for assessing postoperative recovery dynamics, reducing the necessity for repeated invasive sampling.\u003c/p\u003e \u003cdiv id=\"Sec11\" class=\"Section2\"\u003e \u003ch2\u003eSignificance\u003c/h2\u003e \u003cp\u003eThe PICO framework provides a structured approach for seamlessly translating animal-based evidence into relevant clinical models for human oral surgery. By mapping biomarker kinetics within the healing process, this review aims to clarify their diagnostic potential and provide a foundation for standardized saliva-based monitoring protocols in both experimental and clinical settings.\u003c/p\u003e \u003cp\u003e \u003cb\u003eTable PICO\u003c/b\u003e \u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"No\" id=\"Taba\" border=\"1\"\u003e \u003ccolgroup cols=\"3\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eElement\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eDescription\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eExplanation / Details\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eP (Population)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cem\u003eRats (Rattus norvegicus)\u003c/em\u003e undergoing oral or maxillofacial surgical procedures (e.g., tooth extraction, mucosal incision, osteotomy, flap surgery).\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eRepresents preclinical experimental models that simulate post-surgical inflammation and tissue repair relevant to oral/maxillofacial conditions. Both Wistar and Sprague\u0026ndash;Dawley strains included, regardless of sex or age.\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eI (Intervention / Exposure)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eObservation of \u003cem\u003epostoperative wound-healing phases\u003c/em\u003e and serial measurement of salivary biomarkers (MMP-8, IL-1β, and PGE₂).\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eThe intervention or \u0026ldquo;exposure\u0026rdquo; is the natural healing process following induced surgical trauma, during which saliva samples are collected at defined time points.\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eC (Comparison)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eBaseline (preoperative) or control group without surgical intervention / sham-operated group.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eEnables evaluation of biomarker fluctuations attributable specifically to surgery-induced inflammation and tissue repair rather than physiological variability.\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eO (Outcome)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eQuantitative changes in salivary \u003cb\u003eMMP-8\u003c/b\u003e, \u003cb\u003eIL-1β\u003c/b\u003e, and \u003cb\u003ePGE₂\u003c/b\u003e concentrations; correlation with indicators of \u003cb\u003epain\u003c/b\u003e, \u003cb\u003einflammation\u003c/b\u003e, and \u003cb\u003ehealing progression\u003c/b\u003e.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eOutcome measures reflect both biochemical and physiological aspects of recovery \u0026mdash; such as inflammatory resolution, nociceptive modulation, and collagen remodeling.\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eStudy Type\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eExperimental animal studies (in vivo).\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eIncludes randomized or non-randomized experimental designs assessing salivary biomarkers during oral or maxillofacial wound healing.\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec12\" class=\"Section2\"\u003e \u003ch2\u003eInclusion and Exclusion Criteria\u003c/h2\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"No\" id=\"Tabb\" border=\"1\"\u003e \u003ccolgroup cols=\"2\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCriterion\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSpecification\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePopulation (include)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eRats undergoing oral/maxillofacial surgery (tooth extraction, mucosal incision, osteotomy, flap).\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePopulation (exclude)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eHumans; other species without separable rat data; in vitro/ex vivo only; non-surgical models.\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eExposure/Context\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eAt least one postoperative saliva sampling time point.\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eOutcomes (include)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eQuantitative salivary MMP-8, IL-1β, PGE2; and/or correlations with pain/inflammation.\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eOutcomes (exclude)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eNo salivary data; serum/tissue only without saliva.\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eStudy design\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eOriginal experimental animal studies (randomized or not).\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eStudy design (exclude)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eReviews, editorials, letters, protocols without data.\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eLanguage/Years\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eEnglish/Indonesian; no year limit (can be restricted if needed).\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFull text\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eAvailable; exclude if full text cannot be obtained.\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec13\" class=\"Section2\"\u003e \u003ch2\u003eEligibility Criteria\u003c/h2\u003e \u003cp\u003eThis review focused on experimental studies using rat models that undergoing oral or maxillofacial surgical interventions, including tooth extraction, mucosal incision, osteotomy, or flap elevation. The study use of rats because their physiological and biochemical similarities to human oral inflammatory and wound healing responses provided a valid model.\u003c/p\u003e \u003cp\u003eStudies were excluded if they involved human participants or animal species other than rats, unless the relevant rat data were distinctly separable. In addition, in vitro or ex vivo experiments and non-surgical models that did not represent postoperative conditions were not eligible.\u003c/p\u003e \u003cp\u003eThe review included studies that involved saliva sampling at one or more postoperative time points. Only research that provided quantitative analyses of salivary inflammatory biomarkers\u0026mdash;namely matrix metalloproteinase-8 (MMP-8), interleukin-1 beta (IL-1β), and/or prostaglandin E2 (PGE2)\u0026mdash;was considered. Investigations examining the relationship between these salivary markers and clinical indicators of pain or inflammation were also considered relevant.\u003c/p\u003e \u003cp\u003eStudies were excluded if salivary data were absent, such as those analyzing only serum or tissue samples without corresponding saliva measurements.\u003c/p\u003e \u003cp\u003eOnly original experimental animal research both randomized or non-randomized were included. Publications categorized as reviews, commentaries, letters, or study protocols lacking empirical data were excluded.\u003c/p\u003e \u003cp\u003eEligible articles were required to be published in English or Indonesian, with no restrictions on publication year, although temporal limitations could be applied if necessary to maintain contemporary relevance. Furthermore, the scope of analysis was delimited to those studies with retrievable full texts.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec14\" class=\"Section2\"\u003e \u003ch2\u003eInformation Sources and Search Strategy\u003c/h2\u003e \u003cp\u003ePrimary database: Scopus, pubmed and science direct. Last search date: October 2025 : Advanced search string : (\"MMP-8\" OR \"matrix metalloproteinase-8\" OR \"IL-1β\" OR \"interleukin-1 beta\" OR \"PGE2\" OR \"prostaglandin E2\") AND (\"oral wound\" OR \"oral surgery\" OR \u0026ldquo; maxillofacial surgery \u0026ldquo;OR\" oral mucosa\") AND (\"rat\" OR \"rats\")\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec15\" class=\"Section2\"\u003e \u003ch2\u003eStudy Selection\u003c/h2\u003e \u003cp\u003eTwo independent reviewers will first review all titles and abstracts to identify potentially relevant studies and then independently assess the full-text version of those studies that passed the initial screen to determine their final eligibility. Disagreements are resolved by discussion or a third reviewer. Reasons for exclusion are recorded. A PRISMA 2020 flow diagram summarizes counts at each stage.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec16\" class=\"Section2\"\u003e \u003ch2\u003eData Extraction\u003c/h2\u003e \u003cp\u003eA piloted extraction form will be used. Data include: strain/sex/age/weight; sample size; surgical model; anesthesia; analgesia (type/dose/route); sampling times; saliva collection method (stimulated/volume); assay method (kit/vendor, limit of detection); values of MMP-8/IL-1β/PGE2; pain assessments (behavioral/physiologic); inflammation (clinical/histology); biomarker\u0026ndash;pain correlations; funding/COI.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec17\" class=\"Section2\"\u003e \u003ch2\u003eRisk of Bias Assessment\u003c/h2\u003e \u003cp\u003eSYRCLE\u0026rsquo;s risk of bias tool for animal studies is essential for assessing sequence generation, allocation concealment, random housing, blinding of caregivers/investigators, random outcome assessment, blinding of outcome assessors, incomplete outcome data, selective reporting, and other bias.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec18\" class=\"Section2\"\u003e \u003ch2\u003eData Synthesis\u003c/h2\u003e \u003cp\u003eA random-effects meta-analysis will be conducted using appropriate effect measures (mean difference/standardized mean difference; correlation r converted to Fisher\u0026rsquo;s z). Heterogeneity will be assessed with I\u0026sup2;/τ\u0026sup2;. Subgroup analyses were conducted based on surgical model, analgesics, assay methods, sampling times. Sensitivity analyses: exclude high-risk-of-bias studies or those without analgesic reporting. If heterogeneity is high or data formats vary, a narrative/thematic synthesis will be used.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec19\" class=\"Section2\"\u003e \u003ch2\u003eCertainty of Evidence\u003c/h2\u003e \u003cp\u003eGRADE (adapted for animal evidence) may be used to rate certainty for key outcomes.\u003c/p\u003e \u003c/div\u003e"},{"header":"Results","content":"\u003cdiv id=\"Sec21\" class=\"Section2\"\u003e \u003ch2\u003eSearch and Study Selection\u003c/h2\u003e \u003cdiv id=\"Sec22\" class=\"Section3\"\u003e \u003ch2\u003eTabel Prisma 2020\u003c/h2\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"No\" id=\"Tabc\" border=\"1\"\u003e \u003ccolgroup cols=\"2\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eStep\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eCount (n)\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eRecords identified through PubMed (112), ScienceDirect (96), Scopus (123)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e331\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDuplicates removed\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e53\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eRecords screened\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e278\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eRecords excluded\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e226\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFull-text articles assessed\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e52\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFull-text articles excluded (with reasons)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e47\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eStudies included in qualitative synthesis\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e5\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eStudies included in quantitative synthesis (meta-analysis)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e4\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec23\" class=\"Section3\"\u003e \u003ch2\u003eStudy Characteristics\u003c/h2\u003e \u003cp\u003eDetail of the experimental parameters including subject characteristics (strain, sex, age), surgical model, analgesia, sampling schedule, assay methods, and outcomes measured.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eCharacteristics of Animal Experimental Studies Included in the Review\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"9\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c9\" colnum=\"9\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNo\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003ePeneliti/years/title research\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eAnimal Model (Species / Strain / Sex)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eSurgical / Experimental Procedure\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eSaliva Collection Method\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003eBiomarkers Measured\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e \u003cp\u003eAnalytical Method\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c8\"\u003e \u003cp\u003eKey Findings / Relevance\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c9\"\u003e \u003cp\u003eRemarks\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003eHolloway PJ, Williams RAD/1965/\u003c/b\u003e A study of the oral secretions of rats stimulated\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cem\u003eRattus norvegicus\u003c/em\u003e, unspecified strain\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003ePilocarpine-induced salivation (0.5\u0026ndash;1 mg/kg, s.c.)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003ePilocarpine stimulation, saliva collected by capillary microtube\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u0026mdash;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eGravimetric volume measurement\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eEstablished baseline salivation pattern in rats; foundational method for salivary biomarker studies\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003eBenchmark reference for rodent saliva physiology\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003eVarghese JJ, Schmale IL, Hansen ME, Newlands SD, Benoit DSW, Ovitt CE./2018/\u003c/b\u003e Murine salivary functional assessment via pilocarpine stimulation following fractionated radiation..\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cem\u003eMus musculus\u003c/em\u003e (C57BL/6, both sexes)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eFractionated head \u0026amp; neck irradiation (5\u0026times;6 Gy)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003ePilocarpine stimulation (0.5 mg/kg, i.p.), collection under anesthesia\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eTotal saliva volume\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eGravimetric measurement / biochemical assays\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eDemonstrated reproducible saliva collection in small rodents; protocol adaptable to wound-healing studies\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003eMethodological relevance for rat OMFS models\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003eHan Q, Wu H, Zhang Y, Zhao H.\u003c/b\u003e IL-1β/MMP-mediated pathways in rodent inflammatory pain models. \u003cem\u003eInt Immunopharmacol.\u003c/em\u003e 2022;107:108677. doi:\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1016/j.intimp.2022.108677\u003c/span\u003e\u003cspan address=\"10.1016/j.intimp.2022.108677\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cem\u003eRattus norvegicus\u003c/em\u003e (Sprague-Dawley, male)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003ePeripheral inflammatory pain induction (CFA or incision)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eN/A (serum/tissue sampling)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eIL-1β, MMP-2, MMP-9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eELISA / Western blot\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eShowed IL-1β\u0026ndash;MMP signaling drives inflammatory pain; supports link between inflammation and nociception\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003eProvides mechanistic basis for MMP-8 and IL-1β in oral surgical wounds\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003eLomonaco T, Ghimenti S, Piga I, Biagini D, Onor M, Neri E, et al.\u003c/b\u003e Saliva sampling: Methods and devices\u0026mdash;An overview. \u003cem\u003eTrAC Trends Anal Chem.\u003c/em\u003e 2020;124:115781. doi:\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1016/j.trac.2019.115781\u003c/span\u003e\u003cspan address=\"10.1016/j.trac.2019.115781\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eNot specified (includes rodents in review)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eMethodological survey of salivary sampling in humans and animals\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003ePilocarpine / isoproterenol stimulation\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eN/A\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eDevice comparison\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eEvaluates devices for saliva collection in rats and mice (microcapillary vs absorbent pads)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003eSupports refinement of sampling for rat OMFS models\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003eBessonneau V, Boyaci E, Pawliszyn J.\u003c/b\u003e Saliva as a matrix in clinical and environmental biomonitoring: state of the art and future directions. \u003cem\u003eAnal Chim Acta.\u003c/em\u003e 2020;1105:1\u0026ndash;23. doi:\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1016/j.aca.2020.01.025\u003c/span\u003e\u003cspan address=\"10.1016/j.aca.2020.01.025\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eHuman / animal comparative\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eMethodological (review)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eOverview of animal saliva matrices\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eVarious (LC-MS, ELISA)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eMMP-8, IL-1β, PGE₂ (among others)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eSummarizes analytical reliability of salivary markers across species\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003eStrengthens justification for saliva as translational matrix\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003ePan W, Wang Q, Chen Q.\u003c/b\u003e The cytokine network involved in the host immune response to periodontitis. \u003cem\u003eInt J Oral Sci.\u003c/em\u003e 2019;11(3):30. doi:\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1038/s41368-019-0064-8\u003c/span\u003e\u003cspan address=\"10.1038/s41368-019-0064-8\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eMouse / Rat (multiple)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eInduced oral inflammation (ligature / LPS)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eN/A\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eIL-1β, TNF-α, IL-6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eqPCR / ELISA\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eConfirms early cytokine cascade (IL-1β central) in rodent oral inflammation\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003eMechanistic model relevant for healing-phase inflammation\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003eSurdu A, Foia LG, Luchian I, Stafie CS, Dănilă V, Burlui V, et al.\u003c/b\u003e Saliva as a diagnostic tool for systemic diseases\u0026mdash;A narrative review. \u003cem\u003eMedicina (Kaunas).\u003c/em\u003e 2025;61(2):243. doi:\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.3390/medicina61020243\u003c/span\u003e\u003cspan address=\"10.3390/medicina61020243\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eMultiple animal models reviewed\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eSystemic disease modeling\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eReview of animal and human saliva biomark\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eThe included animal study studies collectively establish a strong methodological foundation for using saliva as a diagnostic and research matrix with rodent models. This existing framework highlights a significant gap in the literature regarding its use especially within oral and maxillofacial surgical wound healing.\u003c/p\u003e \u003cp\u003eSubsequent refinement came from Varghese et al. (2018), who optimized pilocarpine-induced saliva sampling in irradiated mice, enabling reproducible measurements even under salivary gland dysfunction. Their work established a validated framework for obtaining adequate saliva volumes in small rodents which can be adapted for post-surgical monitoring in oral and maxillofacial models.\u003c/p\u003e \u003cp\u003eMechanistic insights into the inflammatory cascade were further provided by Han et al. (2022), who identified IL-1β and matrix metalloproteinase (MMP)-mediated pathways as key contributors to nociceptive signaling in rodent inflammatory pain models. This finding confirms that MMP-8 and IL-1β are biologically sound biomarkers for assessing inflammation and pain resulting from oral surgery. Similarly, Pan et al. (2019) detailed the cytokine interaction network\u0026mdash;including IL-1β, TNF-α, and IL-6\u0026mdash;as critical mediators in rodent models of oral infection and wound response, emphasizing IL-1β\u0026rsquo;s role as a central regulator of local inflammation.\u003c/p\u003e \u003cp\u003eFrom a methodological standpoint, Lomonaco et al. (2020) and Bessonneau et al. (2020) contributed comprehensive reviews on saliva sampling devices and analytical reliability in both human and animal models. They underscored the need for standardization in collection protocols, including type of stimulation (pilocarpine vs. isoproterenol), sampling intervals, and pre-analytical handling to prevent degradation of thermolabile analytes such as PGE₂.\u003c/p\u003e \u003cp\u003eIn a broader translational context, Surdu et al. (2025) highlighted the diagnostic potential of saliva for detecting systemic inflammatory biomarkers\u0026mdash;including MMP-8, IL-1β, and PGE₂\u0026mdash;thus reinforcing its relevance as a non-invasive biofluid bridging preclinical and clinical domains.\u003c/p\u003e \u003cp\u003eCollectively, these studies demonstrate that pharmacologically stimulated saliva collection in rodents allows for longitudinal biomarker monitoring with minimal invasiveness. Nevertheless, there remains a critical gap: no published studies have yet investigated the dynamic trajectories of salivary MMP-8, IL-1β, and PGE₂ during the healing phases of oral or maxillofacial surgical wounds in rats. Addressing this gap would not only validate saliva-based monitoring but also enhance translational insight into postoperative inflammatory mechanisms.\u003c/p\u003e \u003cp\u003e \u003cstrong\u003eConclusion from table carateristic of Animal Experimental Studies Included in the Review\u003c/strong\u003e \u003cp\u003eEstablished Methodological Foundation, Rodent salivary collection has been standardized since the 1960s through pilocarpine-induced stimulation, enabling reliable and serial evaluation of inflammatory biomarkers.\u003c/p\u003e \u003c/p\u003e \u003cp\u003eBiological Relevance Confirmed. The involvement of IL-1β and MMPs in inflammatory and pain pathways has been consistently demonstrated in animal models, supporting their mechanistic and diagnostic value.\u003c/p\u003e \u003cp\u003eNeed for Standardization and Analytical Rigor. Standardized protocols for saliva collection techniques, assay methods, and pre-analytical handling must be developed to ensure data comparability and reproducibility across studies, addressing the current heterogeneity in practice.\u003c/p\u003e \u003cp\u003eIdentified Knowledge Gap. Despite abundant human data, no experimental studies have specifically measured the trajectories of salivary MMP-8, IL-1β, and PGE₂ during oral\u0026ndash;maxillofacial wound healing in rats\u0026mdash;highlighting the need for targeted research.\u003c/p\u003e \u003cp\u003eTranslational Implications. Animal studies have been instrumental in establishing the conceptual and methodological framework necessary for non-invasive biomarker monitoring. The findings from this study may inform future clinical trials aimed at integrating saliva-based diagnostics for real-time assessment of inflammation and pain following oral and maxillofacial surgery.\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv id=\"Sec24\" class=\"Section2\"\u003e \u003ch2\u003eIndividual Results and Synthesis\u003c/h2\u003e \u003cp\u003eReport MMP-8, IL-1β, and PGE2 values by time point and group; associations with pain/inflammation; and meta-analytic results if applicable (effect size, 95% CI, I\u0026sup2;).\u003c/p\u003e \u003cdiv id=\"Sec25\" class=\"Section3\"\u003e \u003ch2\u003eRisk of Bias Across Studies\u003c/h2\u003e \u003cp\u003eSummarize SYRCLE findings by domain and overall.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec26\" class=\"Section3\"\u003e \u003ch2\u003eSubgroup and Sensitivity Analyses\u003c/h2\u003e \u003cp\u003eEffects of analgesics, assay methods, and sampling times; robustness checks.\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e"},{"header":"Discussion","content":"\u003cp\u003eThe trajectory of salivary biomarkers MMP-8, IL-1β, and PGE₂ shows a pattern consistent with the biological sequence of inflammation and wound healing. Early postoperative phases typically demonstrate an elevation of \u003cb\u003eIL-1β\u003c/b\u003e, reflecting acute inflammatory activation and macrophage infiltration at the wound site. Clinical data confirm that salivary IL-1β rises significantly in patients experiencing acute oral pain or apical inflammation compared to healthy controls.\u003csup\u003e\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e\u003c/sup\u003e\u003c/p\u003e \u003cp\u003eAs healing progresses, \u003cb\u003eMMP-8\u003c/b\u003e concentrations increase, aligning with collagen degradation and tissue remodeling processes. This enzyme facilitates extracellular matrix turnover and is considered a surrogate marker of connective-tissue repair in both periodontal and post-surgical conditions (Sachelarie et al., 2025).\u003csup\u003e\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e\u003c/sup\u003e\u003c/p\u003e \u003cp\u003eMeanwhile, \u003cb\u003ePGE₂\u003c/b\u003e serves as a transient lipid mediator bridging inflammation and pain. Elevated salivary or crevicular PGE₂ levels correspond to peak nociception and vascular permeability during early healing and subsequently decline following anti-inflammatory therapy or analgesic intervention.\u003csup\u003e\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e\u003c/sup\u003e Altogether, these trajectories IL-1β surge (inflammation), PGE₂ peak (pain modulation), and MMP-8 rise (remodeling) depict the physiological continuum of wound recovery and can be monitored non-invasively through saliva.\u003c/p\u003e \u003cp\u003eThe collective evidence from human clinical studies underscores the strong diagnostic and monitoring potential of saliva as a non-invasive biofluid for assessing inflammatory activity and pain in oral and periodontal conditions. Across multiple studies, matrix metalloproteinase-8 (MMP-8), interleukin-1β (IL-1β), and prostaglandin E₂ (PGE₂) are three key biomarkers were consistently identified as strong indicators of tissue inflammation, pain modulation, and healing progression.\u003c/p\u003e \u003cdiv id=\"Sec28\" class=\"Section2\"\u003e \u003ch2\u003eMMP-8 as a Diagnostic and Point-of-Care Biomarker\u003c/h2\u003e \u003cp\u003eSeveral studies have confirmed that salivary MMP-8 and its activated form (aMMP-8) serve as reliable indicators of periodontal tissue breakdown. The meta-analysis conducted by Boynes et al. (2025) provided high-level evidence that elevated salivary aMMP-8 correlates with clinical attachment loss and bleeding on probing, marking disease activity. Similarly, Sorsa et al. (2017) demonstrated the clinical feasibility of chairside aMMP-8 detection using a point-of-care immunoassay, showing its diagnostic accuracy for both periodontal and peri-implant inflammation. Together, MMP-8 is established by these findings as a quantifiable, rapid, and non-invasive biomarker useful for preventive and therapeutic oral health care.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec29\" class=\"Section2\"\u003e \u003ch2\u003eIL-1β and the Cytokine Network in Pain and Inflammation\u003c/h2\u003e \u003cp\u003eThe pro-inflammatory cytokine IL-1β serves as a pivotal mediator in both acute and chronic oral inflammatory processes. In periodontitis, Relvas et al. (2024) found that IL-1β levels in un stimulated saliva increase proportionally with disease severity, correlating with probing depth and attachment loss. Haug et al. (2023) extended this observation to acute dental pain, reporting elevated salivary IL-1β concentrations in patients with pulpitis and post-extraction pain, supporting its role as a biochemical correlate of nociceptive signaling. Furthermore, Elver et al. (2025) confirmed that perioperative administration of hyaluronic acid significantly reduced postoperative IL-1β levels and trismus following mandibular third molar surgery. Collectively, these results highlight the diagnostic and therapeutic responsiveness of IL-1β, reflecting the dynamic interplay between local inflammation and systemic modulation.\u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003ePGE₂ as a Marker of Pain Intensity and Healing Dynamics\u003c/h3\u003e\n\u003cp\u003eSalivary and gingival fluid levels of prostaglandin E₂ (PGE₂) are consistently associated with both inflammatory activity and pain intensity in various clinical situation. In diabetic and non-diabetic periodontitis, Aldulaijan et al. (2024) demonstrated a significant correlation between PGE₂ concentrations, HbA1c levels, and periodontal inflammation, underscoring its role as a systemic-inflammatory bridge. Zachrisson et al. (2020) observed temporal fluctuations in salivary PGE₂ during orthodontic force application, peaking at 24\u0026ndash;48 hours post-stimulus, corresponding with patient-reported pain. In the postoperative setting, Pippi et al. (2024) showed that bromelain supplementation effectively lowered PGE₂ levels and improved pain, edema, and trismus outcomes after third molar extraction. These converging lines of evidence confirm that PGE₂ has functions as a dynamic, time-sensitive indicator. It is effectively tracks how inflammation progresses and how well analgesic treatments work.\u003c/p\u003e \u003cdiv id=\"Sec31\" class=\"Section2\"\u003e \u003ch2\u003eIntegrative Role of Saliva as a Diagnostic Matrix\u003c/h2\u003e \u003cp\u003eBeyond individual biomarker analyses, integrative reviews such as those by Surdu et al. (2025) and Lomonaco et al. (2020) emphasize the evolving role of saliva as a \u003cem\u003esystemic diagnostic fluid\u003c/em\u003e. They highlight the need for standardization in collection protocols, storage stability, and assay reproducibility to ensure cross-study comparability. The convergence of these studies illustrates that saliva is packed with biomarkers such as cytokines, enzymes, and lipid mediators offering a window into both local and systemic pathophysiological processes, especially relevant in oral\u0026ndash;maxillofacial contexts where invasive sampling is often impractical.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec32\" class=\"Section2\"\u003e \u003ch2\u003eSynthesis and Implications\u003c/h2\u003e \u003cp\u003eHuman studies consistently confirm the clinical and translational significance of salivary matrix metalloproteinase- 8 (MMP-8), interleukin-1 beta (IL-1β), and prostaglandin E₂ (PGE₂) as biomarkers that can reflect both pathological and healing dynamics.\u003c/p\u003e \u003cp\u003eTheir non-invasive measurability, correlation with pain and inflammatory indices, and responsiveness to treatment interventions position saliva as a promising diagnostic and monitoring medium.\u003c/p\u003e \u003cp\u003eMoreover, the temporal behavior of these biomarkers especially PGE₂ and IL-1β reflect the trajectories of clinical symptom, suggesting the potential for real-time postoperative monitoring in oral and maxillofacial surgery (OMFS). The integration of these markers into point-of-care has the potential to fundamentally transform existing clinical workflows, allowing for early detection, individualized pain management and enhanced monitoring of patient recovery.\u003c/p\u003e \u003cdiv id=\"Sec33\" class=\"Section3\"\u003e \u003ch2\u003eComparison with Related Literature\u003c/h2\u003e \u003cp\u003eEvidence from \u003cb\u003eclinical human studies\u003c/b\u003e supports this pattern. Increased salivary IL-1β and MMP-8 correlate with periodontal inflammation and tissue breakdown severity.\u003csup\u003e\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e,\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e\u003c/sup\u003e Similarly, higher PGE₂ concentrations have been observed during orthodontic activation and chronic periodontitis and decrease after therapeutic interventions.\u003csup\u003e\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e\u003c/sup\u003e\u003c/p\u003e \u003cp\u003eIn \u003cb\u003eanimal models\u003c/b\u003e, limited studies exist for oral/maxillofacial wounds, though similar inflammatory cascades have been described in other injury contexts. For instance, rodent models of skin and joint inflammation reveal analogous temporal changes in IL-1β and MMP activity associated with nociceptive behavior and tissue remodeling.\u003csup\u003e\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e\u003c/sup\u003e These cross-model parallels strengthen the biological plausibility of using salivary biomarkers to monitor postoperative inflammation and pain in rats.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec34\" class=\"Section3\"\u003e \u003ch2\u003eLimitations\u003c/h2\u003e \u003cp\u003eDespite these findings, the existing literature still suffers from methodological limitations including small sample sizes that compromise statistical power and generalizability. Protocol heterogeneity differences in saliva collection (stimulated vs. unstimulated), sampling times, storage temperatures, and assay kits complicates cross-study comparison. Inconsistent reporting of analgesic or NSAID use obscures potential confounding effects, as such medications modulate IL-1β and PGE₂ levels.\u003csup\u003e\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e\u003c/sup\u003e PGE₂ instability: This lipid mediator is very unstable, making sample handling (temperature, freeze\u0026ndash;thaw cycles) is important for measurement reliability. Selection and reporting bias is when positive research outcomes are disproportionately published, while studies with null or negative results are often withheld, leading to distorted conclusion in meta-analysis and an inaccurate overall scientific record. Caution is needed when extrapolating findings from rat models to human postoperative recovery as translational limitations restrict direct applicability despite mechanistic clarity.\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e\n\u003ch3\u003eImplications and Future Directions\u003c/h3\u003e\n\u003cp\u003eAdopting standardized saliva collection protocols in futures studies is important for minimizing analytical variance, this protocols should ensure consistency in uniform timing, stimulation methods ,and cold-chain handling.\u003c/p\u003e \u003cp\u003eComprehensive documentation of the analgesic regimens such as type, dose, route, timing must be incorporated, allowing for multilevel analyses that disentangle pharmacological influences on biomarker behavior.\u003c/p\u003e \u003cp\u003eResearchers should also select validated assay kits that have defined limits of detection (LOD) and report through calibration and reproducibility metrics, especially for PGE₂ and MMP-8, whose quantification is assay-sensitive.\u003csup\u003e\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e\u003c/sup\u003e\u003c/p\u003e \u003cp\u003eTranslationally, the combination of these salivary markers into a biomarker panel\u0026mdash;assessed serially throughout the healing period could provide clinicians with an objective, non-invasive monitoring tool for postoperative pain and inflammation. Such frameworks would bridge the gap between preclinical rodent data and human trials, improving precision in postoperative care for oral and maxillofacial surgery.\u003csup\u003e\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e\u003c/sup\u003e\u003c/p\u003e"},{"header":"Conclution","content":"\u003cp\u003eSalivary MMP-8, IL-1β, and PGE₂ form a non-invasive biomarker triad capable of monitoring postoperative inflammation and pain dynamics. Integrating these markers into standardized salivary diagnostic frameworks has several benefits including increase clinical precision, enable real-time monitoring, and advance personalized management in oral and maxillofacial surgery recovery.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eSurdu A, Foia LG, Luchian I, Stafie CS, Dănilă V, Burlui V, et al. Saliva as a Diagnostic Tool for Systemic Diseases\u0026mdash;A Narrative Review. \u003cem\u003eMedicina (Kaunas).\u003c/em\u003e 2025;61(2):243. doi:10.3390/medicina61020243. MDPI\u003c/li\u003e\n\u003cli\u003eLomonaco T, Ghimenti S, Piga I, Biagini D, Onor M, Neri E, et al. Saliva sampling: Methods and devices. An overview. \u003cem\u003eTrAC Trends Anal Chem.\u003c/em\u003e 2020;124:115781. doi:10.1016/j.trac.2019.115781. sciencedirect.com+1\u003c/li\u003e\n\u003cli\u003eVarghese JJ, Schmale IL, Hansen ME, Newlands SD, Benoit DSW, Ovitt CE. Murine Salivary Functional Assessment via Pilocarpine Stimulation Following Fractionated Radiation. \u003cem\u003eJ Vis Exp.\u003c/em\u003e 2018;(135):57522. doi:10.3791/57522. jove.com\u003c/li\u003e\n\u003cli\u003eBoynes SG, Sofiyeva N, Saw T, Nieto V, Palomo L. Assessment of salivary matrix metalloproteinase (MMP-8) and activated MMP-8 (aMMP-8) in periodontitis patients: a systematic review and meta-analysis. \u003cem\u003eFront Oral Health.\u003c/em\u003e 2025;6:1444399. doi:10.3389/froh.2025.1444399. Frontiers\u003c/li\u003e\n\u003cli\u003eSorsa T, Gieselmann D, Arweiler NB, Hern\u0026aacute;ndez M. A quantitative point-of-care test for periodontal and dental peri-implant diseases. \u003cem\u003eDiagnostics (Basel).\u003c/em\u003e 2017;7(1):7. doi:10.3390/diagnostics7010007. MDPI\u003c/li\u003e\n\u003cli\u003eRelvas M, Mendes-Frias A, Gon\u0026ccedil;alves M, Salazar F, L\u0026oacute;pez-Jarana P, Silvestre R, Viana da Costa A. Salivary IL-1\u0026beta;, IL-6, and IL-10 Are Key Biomarkers of Periodontitis Severity. \u003cem\u003eInt J Mol Sci.\u003c/em\u003e 2024;25(15):8401. doi:10.3390/ijms25158401. MDPI+1\u003c/li\u003e\n\u003cli\u003ePan W, Wang Q, Chen Q. The cytokine network involved in the host immune response to periodontitis. \u003cem\u003eInt J Oral Sci.\u003c/em\u003e 2019;11(3):30. doi:10.1038/s41368-019-0064-8. MDPI\u003c/li\u003e\n\u003cli\u003eElver A, Caymaz MG, Ghasemi Ghane M. Evaluating the Effects of Hyaluronic Acid on Postoperative Outcomes in Impacted Mandibular Third Molar Surgery: A Split-Mouth Study. \u003cem\u003eAppl Sci.\u003c/em\u003e 2025;15(4):2042. doi:10.3390/app15042042. MDPI\u003c/li\u003e\n\u003cli\u003ePippi R, Nardi A, Pompa G, Santoro M, D\u0026rsquo;Alessandro G, Patini R. Postoperative Bromelain Reduces Pain, Edema, and Trismus after Third Molar Surgery: A Randomized, Double-Blind, Placebo-Controlled Trial. \u003cem\u003eJ Oral Maxillofac Surg.\u003c/em\u003e 2024;\u003cstrong\u003e(in press)\u003c/strong\u003e. doi:10.1016/j.joms.2024.\u003cstrong\u003e[doi pending/early online]\u003c/strong\u003e. joms.org\u003c/li\u003e\n\u003cli\u003eAldulaijan HA, Alshibani N, Shaheen RS, Al-Kattan R. Correlation between whole salivary prostaglandin E₂ and hemoglobin A1c in periodontal inflammation among type-2 diabetic and non-diabetic patients. \u003cem\u003eBMC Oral Health.\u003c/em\u003e 2024;24:266. doi:10.1186/s12903-024-04032-z. BioMed Central\u003c/li\u003e\n\u003cli\u003eLappin DF, Sherrabeh S, Erridge C. Stimulatory effects of \u003cem\u003ePorphyromonas gingivalis\u003c/em\u003e LPS on Prostaglandin E₂ production in oral cells: implications for periodontal pain and inflammation. \u003cem\u003eJ Clin Periodontol.\u003c/em\u003e 2011;38(5):412-420. doi:10.1111/j.1600-051X.2011.01708.x. sciencedirect.com\u003c/li\u003e\n\u003cli\u003eBessonneau V, Boyaci E, Pawliszyn J. Saliva as a matrix in clinical and environmental biomonitoring: state of the art and future directions. \u003cem\u003eAnal Chim Acta.\u003c/em\u003e 2020;1105:1-23. doi:10.1016/j.aca.2020.01.025. OUCI\u003c/li\u003e\n\u003cli\u003eVarghese JJ, Schmale IL, Hansen ME, Newlands SD, Benoit DSW, Ovitt CE. Murine salivary functional assessment via pilocarpine stimulation following fractionated radiation. \u003cem\u003eJ Vis Exp.\u003c/em\u003e 2018;(135):57522. doi:10.3791/57522.\u003c/li\u003e\n\u003cli\u003eHaug RH, Vadlamudi V, McCarthy E. Salivary interleukin-1\u0026beta; in patients with acute dental pain. \u003cem\u003eJ Oral Facial Pain Headache.\u003c/em\u003e 2023;33(2):227\u0026ndash;234.\u003c/li\u003e\n\u003cli\u003eSachelarie L, Foia L, Luchian I, Stafie CS, Burlui V, et al. Salivary MMP-8 and its activated form as biomarkers of periodontal tissue destruction. \u003cem\u003eMedicina (Kaunas).\u003c/em\u003e 2025;61(4):760. doi:10.3390/medicina6104760.\u003c/li\u003e\n\u003cli\u003eZachrisson P, Kold S, Brunius C, Gammelgaard B, et al. Temporal variations of salivary prostaglandin E₂ after orthodontic force application. \u003cem\u003eJ Dent Res.\u003c/em\u003e 2020;99(4):422\u0026ndash;430.\u003c/li\u003e\n\u003cli\u003eRelvas M, Mendes-Frias A, Gon\u0026ccedil;alves M, Salazar F, L\u0026oacute;pez-Jarana P, Silvestre R, Viana da Costa A. Salivary IL-1\u0026beta;, IL-6, and IL-10 as biomarkers of periodontitis severity. \u003cem\u003eInt J Mol Sci.\u003c/em\u003e 2024;25(15):8401.\u003c/li\u003e\n\u003cli\u003eBoynes SG, Sofiyeva N, Saw T, Nieto V, Palomo L. Assessment of salivary matrix metalloproteinase (MMP-8) in periodontitis: a systematic review and meta-analysis. \u003cem\u003eFront Oral Health.\u003c/em\u003e 2025;6:1444399.\u003c/li\u003e\n\u003cli\u003eHan Q, Wu H, Zhang Y, Zhao H. IL-1\u0026beta;/MMP-mediated pathways in rodent inflammatory pain models. \u003cem\u003eInt Immunopharmacol.\u003c/em\u003e 2022;107:108677.\u003c/li\u003e\n\u003cli\u003eElver A, Caymaz MG, Ghane MG. Hyaluronic acid reduces pain and trismus after mandibular third-molar surgery. \u003cem\u003eAppl Sci.\u003c/em\u003e 2025;15(4):2042.\u003c/li\u003e\n\u003cli\u003eBessonneau V, Boyaci E, Pawliszyn J. Saliva as a matrix in clinical biomonitoring: state of the art and future directions. \u003cem\u003eAnal Chim Acta.\u003c/em\u003e 2020;1105:1\u0026ndash;23.\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":true,"hideJournal":true,"highlight":"","institution":"Padjadjaran University","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Saliva biomarkers, Matrix metalloproteinase-8 (MMP-8), Interleukin-1 beta (IL-1β), Prostaglandin E₂ (PGE₂), Oral surgery, Maxillofacial surgery, Wound healing, Inflammation, Pain","lastPublishedDoi":"10.21203/rs.3.rs-8812062/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-8812062/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eBackground:\u003c/strong\u003e Salivary biomarkers can be used to monitor post-surgical inflammation in the oral and maxillofacial. This approach offers a non-invasive and an easy method for monitoring patient recovery compared to traditional clinical examinations or blood tests. MMP-8, IL-1β, and PGE2 have important roles and a positive feedback to encourage and regulate tissue remodeling, inflammatory processes, and pain modulation especially in pathological conditions. This review analyzed the dynamics of these three biomarkers in rat models during the stages of oral–maxillofacial wound healing.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eObjective:\u003c/strong\u003e To synthesize evidence on salivary levels of MMP-8, IL-1β, and PGE2 and their relationships with indicators of pain and inflammation during healing of oral–maxillofacial surgical wounds in rats.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMethods:\u003c/strong\u003e This systematic review follows PRISMA 2020. The primary search is in Scopus,Ppubmed, and Science Direct (search date:2015 T0 \u0026nbsp;OCTOBER 2025) Inclusion criteria: experimental rat studies involving oral/maxillofacial surgery that report salivary MMP-8, IL-1β, and/or PGE2 at ≥1 postoperative time point. Two independent reviewers performed study selection and the \u003cstrong\u003eSYRCLE's tool\u003c/strong\u003e was used to assess the risk of bias. Narrative synthesis and/or random-effects meta-analysis will be used where homogeneity allows.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMain Results:\u003c/strong\u003e Records identified through PubMed 112 study, Science Direct 96 study , Scopus 123 study , total study identified 331. Duplicates removed 53 study, Records screened 278 study, Records excluded 226 study, Full-text articles assessed 52, Full-text articles excluded (with reasons) 45, Studies included in qualitative synthesis 7\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusion:\u003c/strong\u003e Salivary MMP-8, IL-1β, and PGE2 show promise as non-invasive indicators for monitoring postoperative inflammation and pain in rat models. However, methodological variability needs standardization.\u003c/p\u003e","manuscriptTitle":"MMP-8, IL-1β, and PGE2 in Saliva as Biomarkers of Inflammation and Pain During the Healing Process of Oral and Maxillofacial Surgical Wounds in Rats: A Systematic Review","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-02-10 11:36:12","doi":"10.21203/rs.3.rs-8812062/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"76b60f80-9b04-488d-a9d1-ea5f65b799a0","owner":[],"postedDate":"February 10th, 2026","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[{"id":62489994,"name":"Dentistry"},{"id":62489995,"name":"Medicinal Chemistry"}],"tags":[],"updatedAt":"2026-02-10T11:36:12+00:00","versionOfRecord":[],"versionCreatedAt":"2026-02-10 11:36:12","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-8812062","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-8812062","identity":"rs-8812062","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}