Trans-alveolar Sliding Buccal Flap for Keratinized Mucosa Augmentation in Posterior Maxilla: A Case Report

Trans-alveolar Sliding Buccal Flap for Keratinized Mucosa Augmentation in Posterior Maxilla: A Case Report | 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 Case Report Trans-alveolar Sliding Buccal Flap for Keratinized Mucosa Augmentation in Posterior Maxilla: A Case Report Shuai Lu, Zhaohan Yu, Yue Guo, Yun Huang, Lin Yang, Siqi Luo, and 2 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6743445/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 Objective. To evaluate a trans-alveolar pedicle half-thickness flap technique for augmenting keratinized mucosa (KM) dimensions around posterior maxillary implants. Materials and Methods. Two patients with KM deficiency in the maxillary posterior region underwent modified surgery. A partial-thickness KM flap with buccal pedicle was dissected across the alveolar ridge, apically repositioned to cover implants, and secured with interrupted sutures. Precise measurements guided mucogingival junction relocation 5 mm apically. Palatal donor sites were protected using concentrated growth factor membranes. Healing abutments were connected 8 weeks post-surgery. Clinical assessments included soft tissue thickness (STT) and KM width at 3-month follow-up. Results. The technique was applied at four implant sites, achieving mean STT of 3.1 ± 0.7 mm and KM width of 4.3 ± 0.6 mm. All sites maintained stable mucosal profiles. Conclusions. This vascularized flap technique simplifies KM augmentation in maxillary molars compared to free gingival grafts, effectively enhancing peri-implant mucosal dimensions through minimally invasive approach. Peri-implant mucosa Trans-alveolar sliding buccal pedicle half-thick flap Maxillary posterior implants Keratinized mucosa thickening Figures Figure 1 Figure 2 Figure 3 Introduction The keratinized mucosa (KM) surrounding dental implants plays an important role in long-term maintenance of implants and the esthetic outcome. The absence of adequate KM or around dental implants, especially in the posterior region, was associated with higher plaque accumulation and gingival inflammation(Chung, Oh, Shotwell, Misch, & Wang, 2006 ). Clinical evidence indicates that the width of KM (> 2 mm) around implants effectively maintains gingival health(Bouri, Bissada, Al-Zahrani, Faddoul, & Nouneh, 2008 ; Tavelli et al., 2021 ), while soft tissue augmentation with autogenous grafts yields improved peri-implant health, manifested by enh4anced KM dimensions (width and thickness), reduced marginal bone loss, and decreased peri-implantitis incidence(Sanz et al., 2022 ; Thoma et al., 2018 ). Soft tissue grafting procedures aim to augment both the width and thickness of peri-implant KM free gingival graft (FGG), most commonly harvested from the posterior hard palate, remain a highly successful technique for treating peri-implant soft tissue defects. The combination of apically positioned flap (AFP) and FGG is considered a well-established technique with proven clinical effcacy for peri-implant KM widening. Multiple surgical modalitis for peri-implant soft tissue augmentation have been proposed: modifications of surgical options(Akolu, Lele, Dodwad, & Yewale, 2023 ; Hassani, Sadrimanesh, Vahdati, & Sadr-eshkevari, 2010 ; G. Tabanella, 2019 ; Tang, Zhang, Zhang, & Peng, 2024 ), soft tissue harvested procedures(Akolu et al., 2023 ; De Greef et al., 2024 ; Urban, Nagy, Werner, & Meyer, 2019 ), connective tissue graft (CTG) (Saqr, Arboleda, & Min, 2024 ; Ustaoğlu, Paksoy, & Gümüş, 2020 ) and substitutes grafting materials including xenogeneic collagen matrices(Huang, Wang, Dai, Sun, & Ding, 2024 ; Giorgio Tabanella, 2022 ) and platelet-rich fibrin (PRF) membranes(Hehn, Schwenk, Striegel, & Schlee, 2016 ; Patnaik et al., 2024 ), all demonstrating favorable outcomes in clinical applications. In the posterior maxilla, particularly around the second molar with buccal KM deficiency following dental implant placement, AFP suturing or vestibular deepening poses major operative challenges due to restricted spatial access and compromised visual field in this anatomically constrained area. Considering the FGG donor site is located in the maxillary palate side, adjacent to the recipient site following APF closure, this case series aims to present a trans-alveolar sliding buccal pedicle half-thick flap technique, which increases the amount of KM around the maxillary posterior implants without the need for connective tissue grafts or application of allograft material, prior to the second stage of the procedure. Materials and methods Clinical Trial Number: Not applicable. Technical note and Surgical schematic diagram (Figure 1) The trans-alveolar sliding buccal pedicle half-thick flap was described as follows: 1. Localization of palatal side horizontal incision: the incision was designed parallel to the alveolar ridge and about 18 mm away from the mucogingival junction (MGJ), according to the following criteria: an average width of 8 mm for alveolar ridge 8 mm, 5 mm reserved on the buccal side for keratinized mucosa width (KMW), and 5 mm reserved on the palatal side to cover the implant. Two vertical releasing incisions were designed at the mesial and distal of the implant, with a distance no less than the length of the horizontal incision (>18 mm). The vertical releasing incisions should extend to 10mm from the top of the alveolar ridge on the buccal side (Fig 1). A periodontal probe (UNC 15; Hu-Friedy, Chicago, IL) was used to measure the size of the incision. 2. Sliding flap preparation: A 15C blade was used to make an incision above the periosteum along the existing horizontal incision. A partial-thickness flap was elevated buccally, extending across the alveolar ridge to the MGJ. The dissection was continued apically while preserving the integrity of the free gingival margin and vascular pedicle. The resultant keratinized flap measured 1.2-2.0 mm in thickness, with the non-keratinized buccal mucosa forming the complete pedicle. The MGJ was identified and the flap was repositioned to ensure coverage of the alveolar ridge by the keratinized tissue component (Fig 1C). 3. Sliding flap fixation: the ideal MGJ position was established by reshaping vestibular depth according to adjacent natural teeth while preserving adequate keratinized mucosa bilaterally on buccal and palatal aspects of the implant following healing abutment placement. Initial fixation involved securing the MGJ to the periosteal apical region using a horizontal mattress suture. Subsequently, the flap was tightly adapted to the recipient site's periosteum along alveolar ridge contours, with palatal corners stabilized using single-interrupted sutures (Fig 1D). Supplementary interrupted sutures were placed along flap margins for additional stabilization. Final flap compaction was achieved through 2-3 horizontal cross mattress sutures (Fig 1E). All surgical sutures were performed using 5/0 non-resorbable monofilament suture (Ethicon J&J, New Brunswick, NJ). The buccal non-keratinized mucosa and vascular pedicle were folded at the MGJ apical extent. 4. Treatment of exposed wound: after the sutures of the sliding flap, the exposed wound at the palatal side was covered with concentrated growth factor (CGF)(Borsani et al., 2018), produced by centrifuging the patient’s blood at alternate and regulated speeds in a specially designed centrifuge (Medifuge, Silfradentsrl, Italy), the CGF was extracted and carefully placed on the exposed periosteum, and fixed with 2-3 horizontal cross mattress sutures using a 5/0 non-resorbable monofilament (Fig 1E). This case report series was prepared in accordance with the CARE guidelines for case reports. Case presentation Two patients with maxillary molar implantation, and loss of KM on the buccal side of the implant during the second stage surgery were treated at Department of Stomatology, the General Hospital of Western Theater Command, using the trans-alveolar sliding buccal pedicle half-thick flap technique mentioned above to increase the width and thickness of KM. Written informed consents were signed after communicating with the soft tissue thickening and widening plan before restoration. Case 1 A 69 year-old male has been wearing partially removable dentures for many years due to missing upper right posterior teeth. Three dental implants were implanted through maxillary sinus external elevation surgery. Prior to the second stage surgery, partial bone resorption was found at the second molar implant, and a lack of KM on the buccal side and alveolar ridge, accompanied by insufficient mucosal thickness. This patient refused bone augmentation again and requested direct restoration on the existing basis. Soft tissue augmentation and repositioning was designed for this case to increase the width and thickness of KM around the second molar implant. Case 2 A 67 year-old woman suffering from osteoporosis and missing left posterior teeth in her upper jaw was consulting for restoration with implants. The patient's first premolar had horizontal bone resorption, and she refused horizontal bone augmentation surgery. A single-ended fixed bridge was designed, supported by implants at the second premolar, first molar, and second molar. Prior to the second stage surgery, the width of the KM on the buccal side of the implant was insufficient at the position of two molars. Following aseptic precautions and facial and oral disinfection, local infiltration anesthesia was performed on the buccal and palatal surgical areas of the alveolar ridge, using 1.7 mL articaine hydrochloride and epinephrine tartrate injection (1:100,000). The mucogingival surgeries were performed by the same experienced periodontist following the technical protocol. Postoperative instructions and medication: Ibuprofen (300 mg, b.i.d., 6 days), Amoxicillin (500 mg, t.i.d., 5 days), and 0.12% chlorhexidine mouthwash (10 mL for 1 minute, 3 times daily, 2 weeks). The patients were also asked to avoid chewing or brushing the surgical site, and strictly prohibit smoking and drinking. Sutures were removed after 2 weeks, and a follow-up visit was conducted 2 months later for the placement of a healing abutment. Surgical procedures and follow-up visits were photo recorded, respectively (Fig. 2 and Fig. 3 ). Results Both surgeries were successfully completed, and the sliding flaps were well fixed without looseness or necrosis. At the first 2-week follow-up after surgery, the wound healed well without any infection detected (Fig. 2 E and Fig. 3 H). The second follow-up visit after surgery was arranged 2 months later; sufficient KM was found covering the alveolar crest and buccal side, and the width increasedobviously. In patient 2, it was found that although the wound in the CGF-covered area healed well, there was insufficient thickness in the soft tissue (Fig. 3 I). The next follow-up was scheduled one month after the installation of the healing abutment, with a pre-restoration impression and observation of the emergence profile. In both patients, a deepened vestibule was formed, and the KM around the implants was sufficient in width and thickness, at least 3 and 2 mm, respectively (Fig. 2 H and Fig. 3 J).Both cases demonstrated favorable clinical outcomes using the aforementioned technique, with stable and sufficient KM around the restorations. Discussion This case report aims to describe a solution for insufficient KM around dental implants in the maxillary posterior region. Implant cases in this area are often encountered in clinical practice, especially in elderly patients and those who have lost their teeth for a long time without restoration, where the alveolar shows buccal bone loss. During the second stage of surgery, insufficient KM is usually found, accompanied by shallowed vestibular, thin mucosa, and coronal displacement of the MGJ, especially in cases requiring bone augmentation and soft tissue release. In Linkevicius Tomas's book 'Zero Bone Loss Concepts', the vertical tissue thickness at the crest may be considered a significant influence on marginal bone stability around implants (Linkevicius, Apse, Grybauskas, & Puisys, 2009 ). Experimental results from other research centers also support the close relationship between soft tissue thickness and loss of crest bone(van Eekeren, van Elsas, Tahmaseb, & Wismeijer, 2017 ). The relocation of MGJ to the top of the alveolar ridge crest often represents insufficient thickness of vertical soft tissue. In addition to insufficient KM width, the two cases mentioned in the article also require an increase in vertical soft tissue thickness. FGG is an effective method for augmentation of KM, usually by obtaining keratinized tissue from the upper palate (Hassani et al., 2010 ). Therefore, when there is a lack of KM on the buccal side of the maxillary posterior tooth area, the donor and recipient areas are adjacent on both sides of the alveolar ridge. In the first case, the patient refused further bone augmentation surgery despite bone absorption at the implant neck. Soft tissue augmentation is the only way to solve problems before restoration. Our initial idea for this case was to obtain a half-thick KM flap from the palatal side and slide it to the buccal side to achieve widening of KM and thickening of the vertical soft tissue thickness synchronously. For patients who are unwilling to undergo multiple surgical steps, such a procedure may be considered impractical, combining three surgical procedures, including APF, FGG, and CTG. Studies about the dimensional changes of FGG showed a reduction of approximately 40% shrinkage of the original graft dimension, while the changes were approximately 10% greater at the implant sites than at the tooth sites (Golmayo et al., 2021 ; Monje, Blasi, Amerio, Sanz-Martin, & Nart, 2022 ). So, we designed the horizontal incision at a distance of about 18 mm from the MGJ: the diameter of the implant is usually 5 mm in the posterior tooth area, covering 5 mm on the buccal and palatal sides, and then referring to a 50% shrinkage after sliding. For the thickness of the sliding flap, the separation process was steadily controlled and close to the periosteum to ensure the flap with sufficient submucosal tissue, with an average KM thickness of 1.5-2.0 mm. Attention should be paid when separating the non-keratinized mucosa on the apical side of MGJ, as the mucosa thickness of this part significantly decreases. For fixation of the sliding flap, the key point was to reposition the MGJ to the buccal periosteum with a horizontal mattress suture, and the two interrupted sutures (Fig. 1 D and 1 E) assisted fixation of the sliding flap end. Installing a healing abutment during this procedure may assist in the fixation of the sliding flap and prevent mucosal atrophy as a blocking nail. However, as a preliminary attempt at this technique, in order to avoid damaging the blood supply of the mucoperiosteum and facilitate the survival of the sliding flap, the healing abutment was not placed during the operation since the buccal pedicle is relatively thin. Subsequent operations could be considered such as placing healing abutments at the same time, and evaluating the treatment effect. In this study, the CGF was prepared as a membrane and used to cover the palatal wound after flap sliding and be well sutured, this fibrin matrix and platelets contribute to wound healing (Malcangi et al., 2023 ). However, a soft tissue defect was observed at the palatal donor site during the 2 months post-operation follow-up in the second case (Fig. 3 I). This is consistent with the conclusion reported that platelet rich fibrous material does not increase soft tissue thickness alone (Hehn et al., 2016 ). To overcome the limitation of tissue defect, collagen matrix materials can serve as a supplement for soft tissue recovery (Giorgio Tabanella, 2022 ). Conclusion This case series presents a novel combined buccal pedicle flap and trans-alveolar sliding flap technique, a surgical approach for volume augmentation around dental implants, which could be applied in posterior maxillary implant rehabilitation. While initial outcomes suggest improved hard-soft tissue interface preservation, further multicenter studies with extended follow-up (≥ 5 years) are required to assess volumetric stability, complication profiles, and patient-reported outcomes. Declarations These authors contributed equally to this work. Acknowledgements The authors were grateful to Dr. Yong He and Dr. Shuyong Yang for their clinical support in patient management and technical guidance during specialized dental procedures. Special recognition was given to Dongwen Li for optimizing equipment logistics and maintaining operational efficiency. Funding Declaration ： No Funding. Author Contributions Shuai Lu: conceptualization, investigation, writing – original draft, methodology, data curation, formal analysis. Zhaohan Yu: investigation, data curation, writing – original draft, formal analysis. Yue Guo: conceptualization, supervision. Yun Huang: data curation, writing – original draft. Lin Yang: data curation, writing – original draft. Siqi Luo: formal analysis, writing – original draft, software. Yuanjiao Chen: conceptualization, investigation, methodology, writing – review and editing, data curation. Yan Guo: formal analysis, writing – original draft, writing – review and editing, data curation. Patient Consent Written informed consent was obtained from the patients for the publication of this case report, including the description of the implant surgery and the intraoral photographs presented in this manuscript. A copy of the signed consent form is available from the corresponding author upon request. Conflicts of Interest The authors declare no conflicts of interest. References Akolu, P., Lele, P., Dodwad, V., & Yewale, M. (2023). The Buccal Pedicle Sliding Flap Technique for Keratinized Tissue Augmentation During the Second-Stage Surgery: A Report of Two Cases. Cureus, 15 (10), e46362. Retrieved from http://dx.doi.org/10.7759/cureus.46362. doi:10.7759/cureus.46362 Borsani, E., Bonazza, V., Buffoli, B., Nocini, P. F., Albanese, M., Zotti, F., . . . Rodella, L. F. (2018). 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Titanium-Prepared Platelet-Rich Fibrin Versus Connective Tissue Graft on Peri-Implant Soft Tissue Thickening and Keratinized Mucosa Width: A Randomized, Controlled Trial. J Oral Maxillofac Surg, 78 (7), 1112-1123. doi:10.1016/j.joms.2020.02.019 van Eekeren, P., van Elsas, P., Tahmaseb, A., & Wismeijer, D. (2017). The influence of initial mucosal thickness on crestal bone change in similar macrogeometrical implants: a prospective randomized clinical trial. Clinical Oral Implants Research, 28 (2), 214-218. Retrieved from https://onlinelibrary.wiley.com/doi/abs/10.1111/clr.12784. doi:https://doi.org/10.1111/clr.12784 Additional Declarations No competing interests reported. Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-6743445","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Case Report","associatedPublications":[],"authors":[{"id":493334662,"identity":"5fdb8496-10bd-41bc-b8e8-bfa0a0011e59","order_by":0,"name":"Shuai Lu","email":"","orcid":"","institution":"General Hospital of Western Theater Command PLA","correspondingAuthor":false,"prefix":"","firstName":"Shuai","middleName":"","lastName":"Lu","suffix":""},{"id":493334663,"identity":"0aeaf685-49a9-4ddf-8e0d-28c2dd53d0a2","order_by":1,"name":"Zhaohan Yu","email":"","orcid":"","institution":"General Hospital of Western Theater Command PLA","correspondingAuthor":false,"prefix":"","firstName":"Zhaohan","middleName":"","lastName":"Yu","suffix":""},{"id":493334664,"identity":"489439ab-02d1-43db-b14a-f24824590256","order_by":2,"name":"Yue Guo","email":"","orcid":"","institution":"General Hospital of Western Theater Command PLA","correspondingAuthor":false,"prefix":"","firstName":"Yue","middleName":"","lastName":"Guo","suffix":""},{"id":493334665,"identity":"4d6d1257-dac5-4528-b13a-91f98dfe7183","order_by":3,"name":"Yun Huang","email":"","orcid":"","institution":"General Hospital of Western Theater Command PLA","correspondingAuthor":false,"prefix":"","firstName":"Yun","middleName":"","lastName":"Huang","suffix":""},{"id":493334666,"identity":"b140e827-9c3d-4ff9-8769-c798304b3c27","order_by":4,"name":"Lin Yang","email":"","orcid":"","institution":"General Hospital of Western Theater Command PLA","correspondingAuthor":false,"prefix":"","firstName":"Lin","middleName":"","lastName":"Yang","suffix":""},{"id":493334667,"identity":"e3451c0b-2a39-41f8-88d4-6055de883ea9","order_by":5,"name":"Siqi Luo","email":"","orcid":"","institution":"General Hospital of Western Theater Command PLA","correspondingAuthor":false,"prefix":"","firstName":"Siqi","middleName":"","lastName":"Luo","suffix":""},{"id":493334672,"identity":"81223070-1484-4f0a-9fb4-4677fade6cab","order_by":6,"name":"Yuanjiao Chen","email":"","orcid":"","institution":"General Hospital of Western Theater Command PLA","correspondingAuthor":false,"prefix":"","firstName":"Yuanjiao","middleName":"","lastName":"Chen","suffix":""},{"id":493334673,"identity":"5e2a5cc9-1b0d-49bc-98d2-25c38f0c7592","order_by":7,"name":"Yan Guo","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAtUlEQVRIiWNgGAWjYBACNvmHDQc+/Kix42dvIFILH0Ny48GZPceSJXsOEKlFjiG9+TAHGzPjhhsJxDqM4WDDYQYeNmbJmY833mCosYkmrIWxseFwgYUMH790WrEFw7G03AaCWpgZGw7PANkyO8dMAsgmQgsbUBkPyC83zxCrhQem5QYPsVqAyqCBDPRLAjF+kZ/B/vgDJCoPb7zxocaGsBZkYCCRQIpyiBZSdYyCUTAKRsHIAADKFj80ij0PDQAAAABJRU5ErkJggg==","orcid":"","institution":"General Hospital of Western Theater Command PLA","correspondingAuthor":true,"prefix":"","firstName":"Yan","middleName":"","lastName":"Guo","suffix":""}],"badges":[],"createdAt":"2025-05-25 11:38:23","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-6743445/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-6743445/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":88102478,"identity":"788a7006-b9d3-4902-874c-6200aa2572cc","added_by":"auto","created_at":"2025-08-01 11:39:39","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":18862683,"visible":true,"origin":"","legend":"\u003cp\u003eSchematic diagram of the operation of widening and thickening KM using the sliding flap. (A) Insufficient KM on the buccal and coronal sides of the implant before the second stage surgery for maxillary posterior tooth implantation. (B) Horizontal incision of the palate, stealthy separation of the half-thick flap, crossing the alveolar ridge to the deep buccal region. (C) Slide the half-thick flap towards the vestibular to cover the crown, buccal, and palate of the implant with KM, the un-keratinized mucosa was folded. (D) MGJ repositioning and wound dealing: buccal side fixation using horizontal mattress suture and the end of the sliding flap using interrupted sutures, exposed wound covered with the CGF. (E) horizontal cross mattress suture to fix the sliding flap and the CGF, observed from the occlusion.\u003c/p\u003e","description":"","filename":"fig1.png","url":"https://assets-eu.researchsquare.com/files/rs-6743445/v1/10916cec5bdb82616a1a27bf.png"},{"id":88099420,"identity":"aad93ef2-1041-4f53-9f7a-8206d258fbff","added_by":"auto","created_at":"2025-08-01 11:15:39","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":5192145,"visible":true,"origin":"","legend":"\u003cp\u003eSurgical procedures in patient 1. (A) Initial status of the second molar implant before the second stage surgery. (B) Sliding flap design and incisions. (C) KM augmentation and repositioning. (D) Suturing and wound treatment. (E) Removing the sutures two weeks after surgery. (F) Two months after surgery. (G) Second stage surgery. (H) Emergence profile with sufficient KM, three months after surgery.\u003c/p\u003e","description":"","filename":"fig2.png","url":"https://assets-eu.researchsquare.com/files/rs-6743445/v1/d6dafb4cd14591445b0cc501.png"},{"id":88099415,"identity":"08367288-38e4-488b-be1a-d4d8edd0b5a3","added_by":"auto","created_at":"2025-08-01 11:15:39","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":6297788,"visible":true,"origin":"","legend":"\u003cp\u003eSurgical procedures in patient 2. (A) Initial status of the second molar implant before the second stage surgery. (B) Sliding flap design and incisions. (C) Stealthy separation of the half-thick flap. (D) KM augmentation and repositioning. (E) Fixation and suturing of the sliding flap. (F) Wound treatment: covered with the CGF. (G) The CGF fixation. (H) Removing the sutures two weeks after surgery. (I) Two months after surgery, the KM was sufficient. (J) Emergence profile with sufficient KM, three months after surgery.\u003c/p\u003e","description":"","filename":"fig3.png","url":"https://assets-eu.researchsquare.com/files/rs-6743445/v1/0c77e02155ffdfd3f478e605.png"},{"id":97140745,"identity":"7eddcc7a-f7b6-40e5-b70f-a2ae205fd897","added_by":"auto","created_at":"2025-12-01 10:05:42","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":26621914,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6743445/v1/318eee18-ef2b-4099-b139-daaa1665d9f1.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Trans-alveolar Sliding Buccal Flap for Keratinized Mucosa Augmentation in Posterior Maxilla: A Case Report","fulltext":[{"header":"Introduction","content":"\u003cp\u003eThe keratinized mucosa (KM) surrounding dental implants plays an important role in long-term maintenance of implants and the esthetic outcome. The absence of adequate KM or around dental implants, especially in the posterior region, was associated with higher plaque accumulation and gingival inflammation(Chung, Oh, Shotwell, Misch, \u0026amp; Wang, \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e2006\u003c/span\u003e). Clinical evidence indicates that the width of KM (\u0026gt;\u0026thinsp;2 mm) around implants effectively maintains gingival health(Bouri, Bissada, Al-Zahrani, Faddoul, \u0026amp; Nouneh, \u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e2008\u003c/span\u003e; Tavelli et al., \u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e2021\u003c/span\u003e), while soft tissue augmentation with autogenous grafts yields improved peri-implant health, manifested by enh4anced KM dimensions (width and thickness), reduced marginal bone loss, and decreased peri-implantitis incidence(Sanz et al., \u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e2022\u003c/span\u003e; Thoma et al., \u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e2018\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eSoft tissue grafting procedures aim to augment both the width and thickness of peri-implant KM free gingival graft (FGG), most commonly harvested from the posterior hard palate, remain a highly successful technique for treating peri-implant soft tissue defects. The combination of apically positioned flap (AFP) and FGG is considered a well-established technique with proven clinical effcacy for peri-implant KM widening. Multiple surgical modalitis for peri-implant soft tissue augmentation have been proposed: modifications of surgical options(Akolu, Lele, Dodwad, \u0026amp; Yewale, \u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e2023\u003c/span\u003e; Hassani, Sadrimanesh, Vahdati, \u0026amp; Sadr-eshkevari, \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e2010\u003c/span\u003e; G. Tabanella, \u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e2019\u003c/span\u003e; Tang, Zhang, Zhang, \u0026amp; Peng, \u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e2024\u003c/span\u003e), soft tissue harvested procedures(Akolu et al., \u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e2023\u003c/span\u003e; De Greef et al., \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e2024\u003c/span\u003e; Urban, Nagy, Werner, \u0026amp; Meyer, \u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e2019\u003c/span\u003e), connective tissue graft (CTG) (Saqr, Arboleda, \u0026amp; Min, \u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e2024\u003c/span\u003e; Ustaoğlu, Paksoy, \u0026amp; G\u0026uuml;m\u0026uuml;ş, \u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e2020\u003c/span\u003e) and substitutes grafting materials including xenogeneic collagen matrices(Huang, Wang, Dai, Sun, \u0026amp; Ding, \u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e2024\u003c/span\u003e; Giorgio Tabanella, \u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e2022\u003c/span\u003e) and platelet-rich fibrin (PRF) membranes(Hehn, Schwenk, Striegel, \u0026amp; Schlee, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e2016\u003c/span\u003e; Patnaik et al., \u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e2024\u003c/span\u003e), all demonstrating favorable outcomes in clinical applications.\u003c/p\u003e\u003cp\u003eIn the posterior maxilla, particularly around the second molar with buccal KM deficiency following dental implant placement, AFP suturing or vestibular deepening poses major operative challenges due to restricted spatial access and compromised visual field in this anatomically constrained area. Considering the FGG donor site is located in the maxillary palate side, adjacent to the recipient site following APF closure, this case series aims to present a trans-alveolar sliding buccal pedicle half-thick flap technique, which increases the amount of KM around the maxillary posterior implants without the need for connective tissue grafts or application of allograft material, prior to the second stage of the procedure.\u003c/p\u003e"},{"header":"Materials and methods","content":"\u003cp\u003e\u003cstrong\u003eClinical Trial Number:\u003c/strong\u003e Not applicable.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTechnical note and Surgical schematic diagram (Figure 1)\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe trans-alveolar sliding buccal pedicle half-thick flap was described as follows:\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e1. Localization of palatal side horizontal incision:\u003c/strong\u003e the incision was designed parallel to the alveolar ridge and about 18 mm away from the mucogingival junction (MGJ), according to the following criteria: an average width of 8 mm for alveolar ridge 8 mm, 5 mm reserved on the buccal side for keratinized mucosa width (KMW), and 5 mm reserved on the palatal side to cover the implant. Two vertical releasing incisions were designed at the mesial and distal of the implant, with a distance no less than the length of the horizontal incision (\u0026gt;18 mm). The vertical releasing incisions should extend to 10mm from the top of the alveolar ridge on the buccal side (Fig 1). A periodontal probe (UNC 15; Hu-Friedy, Chicago, IL) was used to measure the size of the incision.\u003c/p\u003e\n\u003cp\u003e2. \u003cstrong\u003eSliding flap preparation:\u0026nbsp;\u003c/strong\u003eA 15C blade was used to make an incision above the periosteum along the existing horizontal incision. A partial-thickness flap was elevated buccally, extending across the alveolar ridge to the MGJ. The dissection was continued apically while preserving the integrity of the free gingival margin and vascular pedicle. The resultant keratinized flap measured 1.2-2.0 mm in thickness, with the non-keratinized buccal mucosa forming the complete pedicle. The MGJ was identified and the flap was repositioned to ensure coverage of the alveolar ridge by the keratinized tissue component (Fig 1C).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e3. \u003cstrong\u003eSliding flap fixation:\u0026nbsp;\u003c/strong\u003ethe ideal MGJ position was established by reshaping vestibular depth according to adjacent natural teeth while preserving adequate keratinized mucosa bilaterally on buccal and palatal aspects of the implant following healing abutment placement. Initial fixation involved securing the MGJ to the periosteal apical region using a horizontal mattress suture. Subsequently, the flap was tightly adapted to the recipient site\u0026apos;s periosteum along alveolar ridge contours, with palatal corners stabilized using single-interrupted sutures (Fig 1D). Supplementary interrupted sutures were placed along flap margins for additional stabilization. Final flap compaction was achieved through 2-3 horizontal cross mattress sutures (Fig 1E). All surgical sutures were performed using 5/0 non-resorbable monofilament suture (Ethicon J\u0026amp;J, New Brunswick, NJ). The buccal non-keratinized mucosa and vascular pedicle were folded at the MGJ apical extent.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e4. Treatment of exposed wound:\u0026nbsp;\u003c/strong\u003eafter the sutures of the sliding flap, the exposed wound at the palatal side was covered with concentrated growth factor (CGF)(Borsani et al., 2018), produced by centrifuging the patient\u0026rsquo;s blood at alternate and regulated speeds in a specially designed centrifuge (Medifuge, Silfradentsrl, Italy), the CGF was extracted and carefully placed on the exposed periosteum, and fixed with 2-3 horizontal cross mattress sutures using a 5/0 non-resorbable monofilament (Fig 1E).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eThis case report series was prepared in accordance with the CARE guidelines for case reports.\u003c/p\u003e"},{"header":"Case presentation","content":"\u003cp\u003eTwo patients with maxillary molar implantation, and loss of KM on the buccal side of the implant during the second stage surgery were treated at Department of Stomatology, the General Hospital of Western Theater Command, using the trans-alveolar sliding buccal pedicle half-thick flap technique mentioned above to increase the width and thickness of KM. Written informed consents were signed after communicating with the soft tissue thickening and widening plan before restoration.\u003c/p\u003e\n\u003ch3\u003eCase 1\u003c/h3\u003e\n\u003cp\u003eA 69 year-old male has been wearing partially removable dentures for many years due to missing upper right posterior teeth. Three dental implants were implanted through maxillary sinus external elevation surgery. Prior to the second stage surgery, partial bone resorption was found at the second molar implant, and a lack of KM on the buccal side and alveolar ridge, accompanied by insufficient mucosal thickness. This patient refused bone augmentation again and requested direct restoration on the existing basis. Soft tissue augmentation and repositioning was designed for this case to increase the width and thickness of KM around the second molar implant.\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\n\u003ch3\u003eCase 2\u003c/h3\u003e\n\u003cp\u003eA 67 year-old woman suffering from osteoporosis and missing left posterior teeth in her upper jaw was consulting for restoration with implants. The patient's first premolar had horizontal bone resorption, and she refused horizontal bone augmentation surgery. A single-ended fixed bridge was designed, supported by implants at the second premolar, first molar, and second molar. Prior to the second stage surgery, the width of the KM on the buccal side of the implant was insufficient at the position of two molars.\u003c/p\u003e\u003cp\u003eFollowing aseptic precautions and facial and oral disinfection, local infiltration anesthesia was performed on the buccal and palatal surgical areas of the alveolar ridge, using 1.7 mL articaine hydrochloride and epinephrine tartrate injection (1:100,000). The mucogingival surgeries were performed by the same experienced periodontist following the technical protocol.\u003c/p\u003e\u003cp\u003ePostoperative instructions and medication: Ibuprofen (300 mg, b.i.d., 6 days), Amoxicillin (500 mg, t.i.d., 5 days), and 0.12% chlorhexidine mouthwash (10 mL for 1 minute, 3 times daily, 2 weeks). The patients were also asked to avoid chewing or brushing the surgical site, and strictly prohibit smoking and drinking. Sutures were removed after 2 weeks, and a follow-up visit was conducted 2 months later for the placement of a healing abutment. Surgical procedures and follow-up visits were photo recorded, respectively (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e and Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e).\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003eBoth surgeries were successfully completed, and the sliding flaps were well fixed without looseness or necrosis. At the first 2-week follow-up after surgery, the wound healed well without any infection detected (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eE and Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003eH). The second follow-up visit after surgery was arranged 2 months later; sufficient KM was found covering the alveolar crest and buccal side, and the width increasedobviously. In patient 2, it was found that although the wound in the CGF-covered area healed well, there was insufficient thickness in the soft tissue (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003eI). The next follow-up was scheduled one month after the installation of the healing abutment, with a pre-restoration impression and observation of the emergence profile. In both patients, a deepened vestibule was formed, and the KM around the implants was sufficient in width and thickness, at least 3 and 2 mm, respectively (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eH and Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003eJ).Both cases demonstrated favorable clinical outcomes using the aforementioned technique, with stable and sufficient KM around the restorations.\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eThis case report aims to describe a solution for insufficient KM around dental implants in the maxillary posterior region. Implant cases in this area are often encountered in clinical practice, especially in elderly patients and those who have lost their teeth for a long time without restoration, where the alveolar shows buccal bone loss. During the second stage of surgery, insufficient KM is usually found, accompanied by shallowed vestibular, thin mucosa, and coronal displacement of the MGJ, especially in cases requiring bone augmentation and soft tissue release. In Linkevicius Tomas's book 'Zero Bone Loss Concepts', the vertical tissue thickness at the crest may be considered a significant influence on marginal bone stability around implants (Linkevicius, Apse, Grybauskas, \u0026amp; Puisys, \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e2009\u003c/span\u003e). Experimental results from other research centers also support the close relationship between soft tissue thickness and loss of crest bone(van Eekeren, van Elsas, Tahmaseb, \u0026amp; Wismeijer, \u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e2017\u003c/span\u003e). The relocation of MGJ to the top of the alveolar ridge crest often represents insufficient thickness of vertical soft tissue. In addition to insufficient KM width, the two cases mentioned in the article also require an increase in vertical soft tissue thickness.\u003c/p\u003e\u003cp\u003eFGG is an effective method for augmentation of KM, usually by obtaining keratinized tissue from the upper palate (Hassani et al., \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e2010\u003c/span\u003e). Therefore, when there is a lack of KM on the buccal side of the maxillary posterior tooth area, the donor and recipient areas are adjacent on both sides of the alveolar ridge. In the first case, the patient refused further bone augmentation surgery despite bone absorption at the implant neck. Soft tissue augmentation is the only way to solve problems before restoration. Our initial idea for this case was to obtain a half-thick KM flap from the palatal side and slide it to the buccal side to achieve widening of KM and thickening of the vertical soft tissue thickness synchronously. For patients who are unwilling to undergo multiple surgical steps, such a procedure may be considered impractical, combining three surgical procedures, including APF, FGG, and CTG.\u003c/p\u003e\u003cp\u003eStudies about the dimensional changes of FGG showed a reduction of approximately 40% shrinkage of the original graft dimension, while the changes were approximately 10% greater at the implant sites than at the tooth sites (Golmayo et al., \u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e2021\u003c/span\u003e; Monje, Blasi, Amerio, Sanz-Martin, \u0026amp; Nart, \u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e2022\u003c/span\u003e). So, we designed the horizontal incision at a distance of about 18 mm from the MGJ: the diameter of the implant is usually 5 mm in the posterior tooth area, covering 5 mm on the buccal and palatal sides, and then referring to a 50% shrinkage after sliding. For the thickness of the sliding flap, the separation process was steadily controlled and close to the periosteum to ensure the flap with sufficient submucosal tissue, with an average KM thickness of 1.5-2.0 mm. Attention should be paid when separating the non-keratinized mucosa on the apical side of MGJ, as the mucosa thickness of this part significantly decreases.\u003c/p\u003e\u003cp\u003eFor fixation of the sliding flap, the key point was to reposition the MGJ to the buccal periosteum with a horizontal mattress suture, and the two interrupted sutures (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003eD and \u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003eE) assisted fixation of the sliding flap end. Installing a healing abutment during this procedure may assist in the fixation of the sliding flap and prevent mucosal atrophy as a blocking nail. However, as a preliminary attempt at this technique, in order to avoid damaging the blood supply of the mucoperiosteum and facilitate the survival of the sliding flap, the healing abutment was not placed during the operation since the buccal pedicle is relatively thin. Subsequent operations could be considered such as placing healing abutments at the same time, and evaluating the treatment effect.\u003c/p\u003e\u003cp\u003eIn this study, the CGF was prepared as a membrane and used to cover the palatal wound after flap sliding and be well sutured, this fibrin matrix and platelets contribute to wound healing (Malcangi et al., \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e2023\u003c/span\u003e). However, a soft tissue defect was observed at the palatal donor site during the 2 months post-operation follow-up in the second case (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003eI). This is consistent with the conclusion reported that platelet rich fibrous material does not increase soft tissue thickness alone (Hehn et al., \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e2016\u003c/span\u003e). To overcome the limitation of tissue defect, collagen matrix materials can serve as a supplement for soft tissue recovery (Giorgio Tabanella, \u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e2022\u003c/span\u003e).\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eThis case series presents a novel combined buccal pedicle flap and trans-alveolar sliding flap technique, a surgical approach for volume augmentation around dental implants, which could be applied in posterior maxillary implant rehabilitation. While initial outcomes suggest improved hard-soft tissue interface preservation, further multicenter studies with extended follow-up (\u0026ge;\u0026thinsp;5 years) are required to assess volumetric stability, complication profiles, and patient-reported outcomes.\u003c/p\u003e"},{"header":"Declarations","content":"These authors contributed equally to this work.\n\u003cp\u003e\u003cstrong\u003eAcknowledgements\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors were grateful to Dr. Yong He and Dr. Shuyong Yang for their clinical support in patient management and technical guidance during specialized dental procedures. Special recognition was given to Dongwen Li for optimizing equipment logistics and maintaining operational efficiency.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding Declaration\u003c/strong\u003e\u003cstrong\u003e：\u003c/strong\u003eNo Funding.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthor Contributions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eShuai Lu:\u0026nbsp;\u003c/strong\u003econceptualization, investigation, writing\u0026nbsp;–\u0026nbsp;original draft, methodology, data curation, formal analysis. \u003cstrong\u003eZhaohan Yu:\u003c/strong\u003e investigation, data curation, writing\u0026nbsp;–\u0026nbsp;original draft, formal analysis. \u003cstrong\u003eYue Guo:\u0026nbsp;\u003c/strong\u003econceptualization, supervision. \u003cstrong\u003eYun Huang:\u0026nbsp;\u003c/strong\u003edata curation, writing – original draft. \u003cstrong\u003eLin Yang:\u003c/strong\u003edata curation, writing – original draft. \u003cstrong\u003eSiqi Luo:\u003c/strong\u003e formal analysis, writing – original draft, software. \u003cstrong\u003eYuanjiao Chen:\u0026nbsp;\u003c/strong\u003econceptualization, investigation, methodology, writing\u0026nbsp;–\u0026nbsp;review and editing, data curation. \u003cstrong\u003eYan Guo:\u003c/strong\u003e formal analysis, writing – original draft, writing – review and editing, data curation.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003ePatient Consent\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eWritten informed consent was obtained from the patients for the publication of this case report, including the description of the implant surgery and the intraoral photographs presented in this manuscript. A copy of the signed consent form is available from the corresponding author upon request. \u0026nbsp;\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConflicts of Interest\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare no conflicts of interest.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n \u003cli\u003eAkolu, P., Lele, P., Dodwad, V., \u0026amp; Yewale, M. (2023). The Buccal Pedicle Sliding Flap Technique for Keratinized Tissue Augmentation During the Second-Stage Surgery: A Report of Two Cases. \u003cem\u003eCureus, 15\u003c/em\u003e(10), e46362. Retrieved from http://dx.doi.org/10.7759/cureus.46362. doi:10.7759/cureus.46362\u003c/li\u003e\n \u003cli\u003eBorsani, E., Bonazza, V., Buffoli, B., Nocini, P. F., Albanese, M., Zotti, F., . . . Rodella, L. F. (2018). Beneficial Effects of Concentrated Growth Factors and Resveratrol on Human Osteoblasts In Vitro Treated with Bisphosphonates. \u003cem\u003eBioMed Research International, 2018\u003c/em\u003e(1), 4597321. Retrieved from https://onlinelibrary.wiley.com/doi/abs/10.1155/2018/4597321. doi:https://doi.org/10.1155/2018/4597321\u003c/li\u003e\n \u003cli\u003eBouri, A., Jr., Bissada, N., Al-Zahrani, M. S., Faddoul, F., \u0026amp; Nouneh, I. (2008). Width of keratinized gingiva and the health status of the supporting tissues around dental implants. \u003cem\u003eInt J Oral Maxillofac Implants, 23\u003c/em\u003e(2), 323-326.\u003c/li\u003e\n \u003cli\u003eChung, D. M., Oh, T.-J., Shotwell, J. L., Misch, C. E., \u0026amp; Wang, H.-L. (2006). Significance of Keratinized Mucosa in Maintenance of Dental Implants With Different Surfaces. \u003cem\u003eJournal of Periodontology, 77\u003c/em\u003e(8), 1410-1420. Retrieved from https://aap.onlinelibrary.wiley.com/doi/abs/10.1902/jop.2006.050393. doi:https://doi.org/10.1902/jop.2006.050393\u003c/li\u003e\n \u003cli\u003eDe Greef, A., Carcuac, O., De Mars, G., Stankov, V., Cortasse, B., Giordani, G., \u0026amp; Van Dooren, E. (2024). The expanded mesh free gingival graft: A novel approach to increase the width of keratinized mucosa. \u003cem\u003eClinical Advances in Periodontics, 14\u003c/em\u003e(3), 157-164. Retrieved from https://aap.onlinelibrary.wiley.com/doi/abs/10.1002/cap.10264. doi:https://doi.org/10.1002/cap.10264\u003c/li\u003e\n \u003cli\u003eGolmayo, P., Barallat, L., Losada, M., Valles, C., Nart, J., \u0026amp; Pascual-La Rocca, A. (2021). Keratinized tissue gain after free gingival graft augmentation procedures around teeth and dental implants: A prospective observational study. \u003cem\u003eJournal of Clinical Periodontology, 48\u003c/em\u003e(2), 302-314. Retrieved from https://onlinelibrary.wiley.com/doi/abs/10.1111/jcpe.13394. doi:https://doi.org/10.1111/jcpe.13394\u003c/li\u003e\n \u003cli\u003eHassani, A., Sadrimanesh, R., Vahdati, S. A., \u0026amp; Sadr-eshkevari, P. (2010). Free Gingival Graft Immobilization: A Pilot Study on a Newly Designed Stent. \u003cem\u003eJournal of Oral Implantology, 36\u003c/em\u003e(2), 123-130. Retrieved from https://doi.org/10.1563/AAID-JOI-D-09-00034. doi:10.1563/aaid-joi-d-09-00034\u003c/li\u003e\n \u003cli\u003eHehn, J., Schwenk, T., Striegel, M., \u0026amp; Schlee, M. (2016). The effect of PRF (platelet-rich fibrin) inserted with a split-flap technique on soft tissue thickening and initial marginal bone loss around implants: results of a randomized, controlled clinical trial. \u003cem\u003eInternational Journal of Implant Dentistry, 2\u003c/em\u003e(1), 13. Retrieved from https://doi.org/10.1186/s40729-016-0044-4. doi:10.1186/s40729-016-0044-4\u003c/li\u003e\n \u003cli\u003eHuang, J.-P., Wang, Y.-Y., Dai, A., Sun, P., \u0026amp; Ding, P.-H. (2024). A combination technique of strip free gingival grafts and xenogeneic collagen matrix in augmenting keratinized mucosa around dental implants: a single-arm clinical trial. \u003cem\u003eBMC Oral Health, 24\u003c/em\u003e(1), 634. Retrieved from https://doi.org/10.1186/s12903-024-04184-y. doi:10.1186/s12903-024-04184-y\u003c/li\u003e\n \u003cli\u003eLinkevicius, T., Apse, P., Grybauskas, S., \u0026amp; Puisys, A. (2009). The influence of soft tissue thickness on crestal bone changes around implants: a 1-year prospective controlled clinical trial. \u003cem\u003eInt J Oral Maxillofac Implants, 24\u003c/em\u003e(4), 712-719.\u003c/li\u003e\n \u003cli\u003eMalcangi, G., Patano, A., Palmieri, G., Di Pede, C., Latini, G., Inchingolo, A. D., . . . Inchingolo, A. M. (2023). Maxillary Sinus Augmentation Using Autologous Platelet Concentrates (Platelet-Rich Plasma, Platelet-Rich Fibrin, and Concentrated Growth Factor) Combined with Bone Graft: A Systematic Review. \u003cem\u003eCells, 12\u003c/em\u003e(13), 1797. Retrieved from https://www.mdpi.com/2073-4409/12/13/1797.\u003c/li\u003e\n \u003cli\u003eMonje, A., Blasi, G., Amerio, E., Sanz-Martin, I., \u0026amp; Nart, J. (2022). Dimensional changes in free epithelialized gingival/mucosal grafts at tooth and implant sites: A prospective cohort study. \u003cem\u003eJournal of Periodontology, 93\u003c/em\u003e(7), 1014-1023. Retrieved from https://aap.onlinelibrary.wiley.com/doi/abs/10.1002/JPER.21-0521. doi:https://doi.org/10.1002/JPER.21-0521\u003c/li\u003e\n \u003cli\u003ePatnaik, B. B., Penmetsa, G. S., Raju, M. S., Haripriya, N., Gera, D., \u0026amp; Ramesh, K. (2024). Peri-implant mucosal enhancement using leukocyte platelet rich fibrin under Sohn\u0026apos;s poncho technique: A randomized controlled clinical trial. \u003cem\u003eClin Adv Periodontics, 14\u003c/em\u003e(2), 134-141. doi:10.1002/cap.10259\u003c/li\u003e\n \u003cli\u003eSanz, M., Schwarz, F., Herrera, D., McClain, P., Figuero, E., Molina, A., . . . Heitz-Mayfield, L. (2022). Importance of keratinized mucosa around dental implants: Consensus report of group 1 of the DGI/SEPA/Osteology Workshop. \u003cem\u003eClinical Oral Implants Research, 33\u003c/em\u003e(S23), 47-55. Retrieved from https://onlinelibrary.wiley.com/doi/abs/10.1111/clr.13956. doi:https://doi.org/10.1111/clr.13956\u003c/li\u003e\n \u003cli\u003eSaqr, A., Arboleda, S., \u0026amp; Min, S. (2024). Semilunar Lingualized Apically Positioned Flap (SLAP) for Peri-implant Soft Tissue Phenotype Modification Therapy Around Mandibular Implants: A Case Report. \u003cem\u003eInt J Periodontics Restorative Dent, 44\u003c/em\u003e(5), 556-567. doi:10.11607/prd.6872\u003c/li\u003e\n \u003cli\u003eTabanella, G. (2019). The buccal pedicle flap technique for periimplant soft tissue boosting. \u003cem\u003eInt J Esthet Dent, 14\u003c/em\u003e(1), 18-18.\u003c/li\u003e\n \u003cli\u003eTabanella, G. (2022). Buccal Pedicle Flap Technique Combined With Porcine Collagen Matrix for Volumetric Augmentation of Peri-Implant Mucosa. \u003cem\u003eClinical Advances in Periodontics, 12\u003c/em\u003e(1), 5-11. Retrieved from https://aap.onlinelibrary.wiley.com/doi/abs/10.1002/cap.10128. doi:https://doi.org/10.1002/cap.10128\u003c/li\u003e\n \u003cli\u003eTang, C., Zhang, P., Zhang, X., \u0026amp; Peng, L. (2024). A modified geometric technique to increase peri-implant keratinized mucosa. \u003cem\u003eJournal of Esthetic and Restorative Dentistry, 36\u003c/em\u003e(8), 1100-1108. Retrieved from https://onlinelibrary.wiley.com/doi/abs/10.1111/jerd.13202. doi:https://doi.org/10.1111/jerd.13202\u003c/li\u003e\n \u003cli\u003eTavelli, L., Barootchi, S., Avila-Ortiz, G., Urban, I. A., Giannobile, W. V., \u0026amp; Wang, H.-L. (2021). Peri-implant soft tissue phenotype modification and its impact on peri-implant health: A systematic review and network meta-analysis. \u003cem\u003eJournal of Periodontology, 92\u003c/em\u003e(1), 21-44. Retrieved from https://aap.onlinelibrary.wiley.com/doi/abs/10.1002/JPER.19-0716. doi:https://doi.org/10.1002/JPER.19-0716\u003c/li\u003e\n \u003cli\u003eThoma, D. S., Naenni, N., Figuero, E., H\u0026auml;mmerle, C. H. F., Schwarz, F., Jung, R. E., \u0026amp; Sanz-S\u0026aacute;nchez, I. (2018). Effects of soft tissue augmentation procedures on peri-implant health or disease: A systematic review and meta-analysis. \u003cem\u003eClinical Oral Implants Research, 29\u003c/em\u003e(S15), 32-49. Retrieved from https://onlinelibrary.wiley.com/doi/abs/10.1111/clr.13114. doi:https://doi.org/10.1111/clr.13114\u003c/li\u003e\n \u003cli\u003eUrban, I. A., Nagy, K., Werner, S., \u0026amp; Meyer, M. (2019). Evaluation of the Combination of Strip Gingival Grafts and a Xenogeneic Collagen Matrix for the Treatment of Severe Mucogingival Defects: A Human Histologic Study. \u003cem\u003eInt J Periodontics Restorative Dent, 39\u003c/em\u003e(1), 9-14. doi:10.11607/prd.3921\u003c/li\u003e\n \u003cli\u003eUstaoğlu, G., Paksoy, T., \u0026amp; G\u0026uuml;m\u0026uuml;ş, K. (2020). Titanium-Prepared Platelet-Rich Fibrin Versus Connective Tissue Graft on Peri-Implant Soft Tissue Thickening and Keratinized Mucosa Width: A Randomized, Controlled Trial. \u003cem\u003eJ Oral Maxillofac Surg, 78\u003c/em\u003e(7), 1112-1123. doi:10.1016/j.joms.2020.02.019\u003c/li\u003e\n \u003cli\u003evan Eekeren, P., van Elsas, P., Tahmaseb, A., \u0026amp; Wismeijer, D. (2017). The influence of initial mucosal thickness on crestal bone change in similar macrogeometrical implants: a prospective randomized clinical trial. \u003cem\u003eClinical Oral Implants Research, 28\u003c/em\u003e(2), 214-218. Retrieved from https://onlinelibrary.wiley.com/doi/abs/10.1111/clr.12784. doi:https://doi.org/10.1111/clr.12784\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","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":"Peri-implant mucosa, Trans-alveolar sliding buccal pedicle half-thick flap, Maxillary posterior implants, Keratinized mucosa thickening","lastPublishedDoi":"10.21203/rs.3.rs-6743445/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6743445/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eObjective.\u003c/h2\u003e\u003cp\u003eTo evaluate a trans-alveolar pedicle half-thickness flap technique for augmenting keratinized mucosa (KM) dimensions around posterior maxillary implants.\u003c/p\u003e\u003ch2\u003eMaterials and Methods.\u003c/h2\u003e\u003cp\u003eTwo patients with KM deficiency in the maxillary posterior region underwent modified surgery. A partial-thickness KM flap with buccal pedicle was dissected across the alveolar ridge, apically repositioned to cover implants, and secured with interrupted sutures. Precise measurements guided mucogingival junction relocation 5 mm apically. Palatal donor sites were protected using concentrated growth factor membranes. Healing abutments were connected 8 weeks post-surgery. Clinical assessments included soft tissue thickness (STT) and KM width at 3-month follow-up.\u003c/p\u003e\u003ch2\u003eResults.\u003c/h2\u003e\u003cp\u003eThe technique was applied at four implant sites, achieving mean STT of 3.1\u0026thinsp;\u0026plusmn;\u0026thinsp;0.7 mm and KM width of 4.3\u0026thinsp;\u0026plusmn;\u0026thinsp;0.6 mm. All sites maintained stable mucosal profiles.\u003c/p\u003e\u003ch2\u003eConclusions.\u003c/h2\u003e\u003cp\u003eThis vascularized flap technique simplifies KM augmentation in maxillary molars compared to free gingival grafts, effectively enhancing peri-implant mucosal dimensions through minimally invasive approach.\u003c/p\u003e","manuscriptTitle":"Trans-alveolar Sliding Buccal Flap for Keratinized Mucosa Augmentation in Posterior Maxilla: A Case Report","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-08-01 11:15:34","doi":"10.21203/rs.3.rs-6743445/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":"a544108f-6c78-4a30-8a5c-5f71decde2e9","owner":[],"postedDate":"August 1st, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2025-11-29T18:38:26+00:00","versionOfRecord":[],"versionCreatedAt":"2025-08-01 11:15:34","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-6743445","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-6743445","identity":"rs-6743445","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}