A case report of a patient with metal-based complete dentures from a long-term follow-up perspective

A case report of a patient with metal-based complete dentures from a long-term follow-up perspective | 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 A case report of a patient with metal-based complete dentures from a long-term follow-up perspective Hitoshi AKIYAMA This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6458372/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 21 Nov, 2025 Read the published version in BMC Oral Health → Version 1 posted 14 You are reading this latest preprint version Abstract Background: Denture treatment is crucial for edentulous patients to maintain a long and healthy life, as well as restore their chewing function. After complete dentures are fitted, it is not uncommon for them to become ill-fitting due to ridge resorption over time, requiring adjustments or relining procedures. Residual ridge resorption results from the combined influence of various local and systemic factors. There have been no reported cases of patients who have worn complete dentures for an extended period without experiencing significant alveolar ridge resorption. I report a case of a patient who had not visited a dentist or had any adjustments for 28 years after being fitted with complete dentures. Case presentation: The patient, a 56-year-old woman, visited the general dentistry of the Nippon Dental University Hospital in Tokyo in March 1994. The diagnosis was masticatory dysfunction caused by ill-fitting upper and lower complete dentures. The treatment plan aimed to improve oral hygiene, restore the health of the alveolar ridge, and achieve proper occlusal contact with a final prosthetic device. The upper and lower dentures were fitted in May 1994. In November 2022, her artificial tooth broke, and she visited the clinic requesting denture repair for the first time in 28 years. A medical interview revealed that the patient had never visited another dental clinic since having dentures fitted 28 years ago. Although wear of the artificial teeth was observed, when the fitting condition of the upper and lower dentures was checked using fitting test materials, it was confirmed that there were no problems with the fitting condition and that there was almost no alveolar ridge resorption. Conclusion: I report on a patient who has worn the same dentures for 28 years. Although wear of the artificial teeth was observed due to bilateral balanced occlusion, the occlusal balance was appropriately maintained. It has been found that metal-based dentures, when fabricated using proper methods, do not promote alveolar ridge resorption. complete denture ridge resorption occlusal balance metal-based denture bilateral balanced occlusion Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Background As the average life expectancy increases in an ultra-aging society, there is a growing need for prosthetic dental treatments to restore the oral health, function, and quality of life for edentulous patients [1]. Complete denture treatment is crucial for edentulous patients to maintain a long and healthy life, as well as to restore their chewing function. After complete dentures are fitted, it is not uncommon for them to become ill-fitting due to ridge resorption over time, requiring adjustments or relining procedures. Residual ridge resorption is the chronic, progressive reduction in the quantity and quality of the alveolar bone occurring after teeth are extracted [2]. Residual ridge resorption is a result of the influence of many local and systemic factors (patient’s age, traumatic damage, different pathological conditions, mineral metabolism disorders, osteoporosis, hyperparathyroidism, and hormone disbalance) [3]. The continuous ridge resorption smaller the denture bearing area that further reduces stability and retention of the denture [4]. There have been no reported cases of patients who have worn complete dentures for an extended period without experiencing significant alveolar ridge resorption. I report a case of a patient who had not visited a dentist or had any adjustments for 28 years after being fitted with complete dentures. Case presentation The patient, a 56-year-old woman, visited the general dentistry of the Nippon Dental University Hospital in Tokyo in March 1994. The situation at the time of the first visit was confirmed using data stored at the university hospital. The patient's main complaint was, "The upper and lower dentures do not fit together. I feel pain when eating, and it is difficult to speak." The patient's medical history included hypertension, and she was taking medication. Regarding the History of the current illness, after the remaining teeth were extracted due to periodontal disease, a temporary tooth replacement was performed on the old denture. The patient was currently edentulous in both the upper and lower jaws and was wearing resin dentures in both arches (Fig. 2 ). The examination consisted of a medical interview, a research cast examination, an imaging examination using panoramic X-rays, and an oral examination. Panoramic X-ray images revealed moderate resorption of the maxillary ridge, with more significant bone resorption on the left side of the mandible compared to the right side. The diagnosis was masticatory dysfunction caused by ill-fitting upper and lower complete dentures. The treatment plan aimed to improve oral hygiene, restore the health of the alveolar ridge, and subsequently achieve proper occlusal contact with a final prosthetic device. First, individual trays were prepared, and muscle pressure was formed. Selective pressure impressions were then made using dental zinc oxide eugenol-based impression material. After making a working model, a virtual occlusal plane was determined using the bite plate, and the occlusal vertical dimension was determined using the rest space method. After face-bow recording, working casts of the upper and lower jaws were attached to a semi-adjustable articulator. The horizontal jaw position was measured using the Gothic arch tracing method. As a result, the tapping point and the apex were aligned. The occlusion pattern was bilateral balanced occlusion in this case. After polymerization, the polymerized dentures were reattached to the articulator, and final occlusal adjustments were made to the articulator. The upper and lower dentures were fitted in May 1994. The upper and lower metal-based complete dentures are shown in Fig. 1 . The intraoral findings when the dentures were worn are presented in Fig. 2 . After two adjustments, the treatment was completed. The facial appearance was aesthetically restored with the upper and lower complete dentures in place. In November 2022, her artificial tooth broke, and she visited the clinic requesting denture repair for the first time in 28 years. A medical interview revealed that the patient had never visited another dental clinic since having dentures fitted 28 years ago. She said, "I'm so glad that you're still here. I've never been to the dentist since then. My dentures were in good condition, so I've been using the same ones for 28 years." The upper and lower dentures after repair are shown in Fig. 3 . Figure 4 shows the intraoral findings at the patient's 28-year follow-up visit. Figure 5 shows the intraoral findings when the patient was wearing dentures. The dentures, which had been worn for 28 years, were examined in detail. Although wear of the artificial teeth was observed, when the fitting condition of the upper and lower dentures was checked using fitting test materials, it was confirmed that there were no problems with the fitting condition and that there was almost no alveolar ridge resorption (Fig. 6 ). The denture was well adhered to, and the test results showed that the glucosensor value was within normal range at 176 mg/dL. Discussion and Coclusions Atwood reported that continuous ridge resorption in complete denture wearing causes major oral disease [5]. Resorption is the result of the bone remodeling process and the main factors related to the resorption are gender, age, facial structure, edentia, denture wearing habits, number of wearing dentures, oral hygiene, oral parafunction, occlusion, denture quality, food, general health, usage of medications, systemic diseases and osteoporosis [6]. Denture wearing is also very important in alveolar ridge resorption [7]. The number of lower dentures worn is very often related to the period of edentia and alveolar ridge resorption [8]. Individuals who wear their complete dentures continuously day and night have more resorptive changes in the jaws compared to those who wear dentures daily. Bone resorption under the denture base is also an essential kind of denture. Patients with lower frontal natural teeth have more significant resorption of the edentulous maxilla than patients with lower complete dentures or natural teeth [9]. The number of dentures worn and oral hygiene are related to alveolar ridge resorption [10]. Although many of the advantages of metal-based dentures are due to the properties of the metal base itself, the most important ones (better retention, better occlusion, fewer sore spots) accrue because processing changes are eliminated or greatly reduced [11]. In this case, the metal parts of the upper and lower complete dentures were made from cobalt-chromium alloy. According to Watt & MacGregor [12], the maxillary ridge is resorbed from the outside, and no bony changes are observed in the palate. If occlusal balance is achieved correctly, metal-based dentures are thought not to promote ridge resorption because the metal does not cause the denture to deflect and does not apply lateral forces to the ridge. Balanced occlusal arrangement of artificial teeth and balanced occlusion is a specific type of occlusion that preserves the stability of complete dentures. Balanced occlusion comprises the realization of tooth contacts at the working side as well as at the balancing side, at the same time. [13]. When adjusting complete dentures, it is important not to grind down the mucosal surface more than necessary, add resin, or reline the dentures. I report on a patient who has worn the same dentures for 28 years. Although wear of the artificial teeth was observed due to bilateral balanced occlusion, the occlusal balance was appropriately maintained. Balanced occlusion is a favored occlusal design in the setting of artificial teeth in conventional complete dentures, as it preserves the edentulous ridge and enhances the stability of dentures. It has been found that metal-based dentures, when fabricated using proper methods, do not promote alveolar ridge resorption. Limitations This is a case report of a patient who has gone 28 years without visiting a dental clinic. This case report was conducted after the patient received detailed written and verbal explanations, written informed consent was obtained, and approval was obtained from the Ethics Committee of the School of Life Dentistry, Nippon Dental University. Declarations Compliance with ethical standards The ethical committee of Nippon Dental University approved the present study (NDU-T2024-56). As this study involves humans and human data, I declare that it complies with the Declaration of Helsinki. Consent to publish The author has read and agreed to the published version of the manuscript. Author’s contributions HA contributed to the study as the first author and wrote the manuscript, conception, design, acquisition, analysis, and interpretation of data. Conflicts of interest The author reports no conflicts of interest related to the present study. Funding Not applicable. Consent for publication Written informed consent was obtained from the patient for her personal and clinical information and images to be published in this study. References Jurado CA, Azpiazu-Flores FX, Fu C-C, Rojas-Rueda S, Guzman-Perez G, Floriani F. Expediting the rehabilitation of severely resorbed ridges using a combination of CAD-CAM and analog techniques: A case report. medicina 2024,60, 260; https://doi.org/10.3390/medicina60020260. Pham NQ, Gonda T, Maeda Y, Ikebe K. Average rate of ridge resorption in denture treatment: A Systematic Review. J Prosthodont. Res. 2021, 65, 429–437. Knezović-Zlatarić, D. Resorptive changes of maxillary and mandibular bone structures in removable denture wearers. Acta Stomatol Croat 2002, 36, 253–259. Ravi R, Chaudhary N, Dahiya D. Complete denture fabrication and management of severely resorbed mandibular residual ridge in geriatric patient: A case report. EAS J Humanit Cult Stud, 2021. 3, 163–167. DOI: 10.36349/easjhcs.2021.v03i04.004. Atwood DA. Reduction of residual ridges: a major oral disease entity. J Prosthet Dent 1971; 26: 266–279. Carlsson GE. Clinical morbidity and sequelae of treatment with complete dentures. J Prosthet Dent 1998; 79: 17–23. XieQ, Narhi TO, Nevbalainen JM, Wolf J, Alnamo A. Oral status and prosthetic factors related to residual ridge resorption in elderly subjects. Acta Odontol Scand 1997; 55: 306–313. De Baat, C., Kalk W, van't Hof, M.A. Factors connected with alveolar bone resorption among institu-tionalized elderly people. Community Dent Oral Epidemiol 1993; 21: 317–320. Kelly E. Changes caused by a mandibular removable partial denture opposing a maxillary complete denture. J Prosthet Dent 1972; 22: 140–150. Adams LP, Wilding RJ. A photogrammetric method for monitoring changes in the residual alveolar ridge form. J Oral Rehabil 1985;12:443–450. Belfiglio EJ.Using metal bases in making complete dentures. J Prosthet Dent 1987; 58: 314–317. Watt DM, MacGregor AR. Designing complete dentures. 2nd ed. Bristol, United Kingdom: Wright,1986. p.15–23. Poštić S. Influence of balanced occlusion in complete dentures on the decrease in the reduction of an edentulous ridge. Vojnosanit Pregl. 2012; 69: 1055–1060. Additional Declarations No competing interests reported. Cite Share Download PDF Status: Published Journal Publication published 21 Nov, 2025 Read the published version in BMC Oral Health → Version 1 posted Editorial decision: Revision requested 25 Aug, 2025 Reviews received at journal 22 Aug, 2025 Reviewers agreed at journal 14 Aug, 2025 Reviews received at journal 15 Jul, 2025 Reviews received at journal 15 Jul, 2025 Reviewers agreed at journal 10 Jul, 2025 Reviews received at journal 09 Jul, 2025 Reviewers agreed at journal 09 Jul, 2025 Reviewers agreed at journal 09 Jul, 2025 Reviewers invited by journal 09 Jul, 2025 Editor assigned by journal 14 May, 2025 Editor invited by journal 02 May, 2025 Submission checks completed at journal 01 May, 2025 First submitted to journal 01 May, 2025 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-6458372","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Case Report","associatedPublications":[],"authors":[{"id":483324265,"identity":"cbe0f640-d569-4666-86f6-b814c09e38d2","order_by":0,"name":"Hitoshi 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2","display":"","copyAsset":false,"role":"figure","size":129788,"visible":true,"origin":"","legend":"\u003cp\u003eThe oral finding at wearing metal-based complete dentures\u003c/p\u003e","description":"","filename":"Figure2.jpg","url":"https://assets-eu.researchsquare.com/files/rs-6458372/v1/a6b7956a8771e66816776f9b.jpg"},{"id":86662481,"identity":"86b39c7d-16d7-4ee6-8205-993881037a58","added_by":"auto","created_at":"2025-07-14 10:43:30","extension":"jpg","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":162084,"visible":true,"origin":"","legend":"\u003cp\u003eThe upper and lower dentures after repair\u003c/p\u003e","description":"","filename":"Figure3.jpg","url":"https://assets-eu.researchsquare.com/files/rs-6458372/v1/f53a4094cfa9b261dad5658e.jpg"},{"id":86663789,"identity":"80494514-9cf1-4319-a071-84483d6fbc5a","added_by":"auto","created_at":"2025-07-14 10:51:30","extension":"jpg","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":149963,"visible":true,"origin":"","legend":"\u003cp\u003eThe intraoral findings at the time of the patient's visit 28 years later\u003c/p\u003e","description":"","filename":"Figure4.jpg","url":"https://assets-eu.researchsquare.com/files/rs-6458372/v1/ffe40b5a9943b59e2dcd719d.jpg"},{"id":86665838,"identity":"b9ce52cb-dd9c-412c-9fb1-07c85a59f21e","added_by":"auto","created_at":"2025-07-14 11:07:30","extension":"jpg","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":204278,"visible":true,"origin":"","legend":"\u003cp\u003eThe intraoral findings at wearing metal-based complete dentures\u003c/p\u003e","description":"","filename":"Figure5.jpg","url":"https://assets-eu.researchsquare.com/files/rs-6458372/v1/736e301b13b39e2b29a7fa0a.jpg"},{"id":86665114,"identity":"303fb00d-d06a-423a-9067-63aebf85694a","added_by":"auto","created_at":"2025-07-14 10:59:30","extension":"jpg","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":137911,"visible":true,"origin":"","legend":"\u003cp\u003eThe fit of complete dentures using mucosal compatibility test materials\u003c/p\u003e","description":"","filename":"Figure6.jpg","url":"https://assets-eu.researchsquare.com/files/rs-6458372/v1/36b45c3a60c6ad51fb3a401c.jpg"},{"id":96650076,"identity":"2f4b63e2-5acc-4aac-a492-16a4a3fc6952","added_by":"auto","created_at":"2025-11-24 16:06:31","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1380172,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6458372/v1/650b3826-c1d7-40cf-8e3b-bec6d34527dd.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"A case report of a patient with metal-based complete dentures from a long-term follow-up perspective","fulltext":[{"header":"Background","content":"\u003cp\u003eAs the average life expectancy increases in an ultra-aging society, there is a growing need for prosthetic dental treatments to restore the oral health, function, and quality of life for edentulous patients [1]. Complete denture treatment is crucial for edentulous patients to maintain a long and healthy life, as well as to restore their chewing function. After complete dentures are fitted, it is not uncommon for them to become ill-fitting due to ridge resorption over time, requiring adjustments or relining procedures. Residual ridge resorption is the chronic, progressive reduction in the quantity and quality of the alveolar bone occurring after teeth are extracted [2]. Residual ridge resorption is a result of the influence of many local and systemic factors (patient\u0026rsquo;s age, traumatic damage, different pathological conditions, mineral metabolism disorders, osteoporosis, hyperparathyroidism, and hormone disbalance) [3].\u003c/p\u003e\u003cp\u003eThe continuous ridge resorption smaller the denture bearing area that further reduces stability and retention of the denture [4]. There have been no reported cases of patients who have worn complete dentures for an extended period without experiencing significant alveolar ridge resorption. I report a case of a patient who had not visited a dentist or had any adjustments for 28 years after being fitted with complete dentures.\u003c/p\u003e"},{"header":"Case presentation","content":"\u003cp\u003eThe patient, a 56-year-old woman, visited the general dentistry of the Nippon Dental University Hospital in Tokyo in March 1994. The situation at the time of the first visit was confirmed using data stored at the university hospital. The patient's main complaint was, \"The upper and lower dentures do not fit together. I feel pain when eating, and it is difficult to speak.\" The patient's medical history included hypertension, and she was taking medication. Regarding the History of the current illness, after the remaining teeth were extracted due to periodontal disease, a temporary tooth replacement was performed on the old denture. The patient was currently edentulous in both the upper and lower jaws and was wearing resin dentures in both arches (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e2\u003c/span\u003e). The examination consisted of a medical interview, a research cast examination, an imaging examination using panoramic X-rays, and an oral examination. Panoramic X-ray images revealed moderate resorption of the maxillary ridge, with more significant bone resorption on the left side of the mandible compared to the right side. The diagnosis was masticatory dysfunction caused by ill-fitting upper and lower complete dentures. The treatment plan aimed to improve oral hygiene, restore the health of the alveolar ridge, and subsequently achieve proper occlusal contact with a final prosthetic device. First, individual trays were prepared, and muscle pressure was formed. Selective pressure impressions were then made using dental zinc oxide eugenol-based impression material. After making a working model, a virtual occlusal plane was determined using the bite plate, and the occlusal vertical dimension was determined using the rest space method. After face-bow recording, working casts of the upper and lower jaws were attached to a semi-adjustable articulator. The horizontal jaw position was measured using the Gothic arch tracing method. As a result, the tapping point and the apex were aligned. The occlusion pattern was bilateral balanced occlusion in this case. After polymerization, the polymerized dentures were reattached to the articulator, and final occlusal adjustments were made to the articulator. The upper and lower dentures were fitted in May 1994. The upper and lower metal-based complete dentures are shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e1\u003c/span\u003e. The intraoral findings when the dentures were worn are presented in Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e2\u003c/span\u003e. After two adjustments, the treatment was completed. The facial appearance was aesthetically restored with the upper and lower complete dentures in place. In November 2022, her artificial tooth broke, and she visited the clinic requesting denture repair for the first time in 28 years. A medical interview revealed that the patient had never visited another dental clinic since having dentures fitted 28 years ago. She said, \"I'm so glad that you're still here. I've never been to the dentist since then. My dentures were in good condition, so I've been using the same ones for 28 years.\" The upper and lower dentures after repair are shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e3\u003c/span\u003e. Figure\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e4\u003c/span\u003e shows the intraoral findings at the patient's 28-year follow-up visit. Figure\u0026nbsp;\u003cspan refid=\"Fig7\" class=\"InternalRef\"\u003e5\u003c/span\u003e shows the intraoral findings when the patient was wearing dentures. The dentures, which had been worn for 28 years, were examined in detail. Although wear of the artificial teeth was observed, when the fitting condition of the upper and lower dentures was checked using fitting test materials, it was confirmed that there were no problems with the fitting condition and that there was almost no alveolar ridge resorption (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e6\u003c/span\u003e). The denture was well adhered to, and the test results showed that the glucosensor value was within normal range at 176 mg/dL.\u003c/p\u003e"},{"header":"Discussion and Coclusions","content":"\u003cp\u003eAtwood reported that continuous ridge resorption in complete denture wearing causes major oral disease [5]. Resorption is the result of the bone remodeling process and the main factors related to the resorption are gender, age, facial structure, edentia, denture wearing habits, number of wearing dentures, oral hygiene, oral parafunction, occlusion, denture quality, food, general health, usage of medications, systemic diseases and osteoporosis [6]. Denture wearing is also very important in alveolar ridge resorption [7]. The number of lower dentures worn is very often related to the period of edentia and alveolar ridge resorption [8]. Individuals who wear their complete dentures continuously day and night have more resorptive changes in the jaws compared to those who wear dentures daily. Bone resorption under the denture base is also an essential kind of denture. Patients with lower frontal natural teeth have more significant resorption of the edentulous maxilla than patients with lower complete dentures or natural teeth [9]. The number of dentures worn and oral hygiene are related to alveolar ridge resorption [10]. Although many of the advantages of metal-based dentures are due to the properties of the metal base itself, the most important ones (better retention, better occlusion, fewer sore spots) accrue because processing changes are eliminated or greatly reduced [11]. In this case, the metal parts of the upper and lower complete dentures were made from cobalt-chromium alloy. According to Watt \u0026amp; MacGregor [12], the maxillary ridge is resorbed from the outside, and no bony changes are observed in the palate. If occlusal balance is achieved correctly, metal-based dentures are thought not to promote ridge resorption because the metal does not cause the denture to deflect and does not apply lateral forces to the ridge. Balanced occlusal arrangement of artificial teeth and balanced occlusion is a specific type of occlusion that preserves the stability of complete dentures. Balanced occlusion comprises the realization of tooth contacts at the working side as well as at the balancing side, at the same time. [13]. When adjusting complete dentures, it is important not to grind down the mucosal surface more than necessary, add resin, or reline the dentures. I report on a patient who has worn the same dentures for 28 years. Although wear of the artificial teeth was observed due to bilateral balanced occlusion, the occlusal balance was appropriately maintained. Balanced occlusion is a favored occlusal design in the setting of artificial teeth in conventional complete dentures, as it preserves the edentulous ridge and enhances the stability of dentures. It has been found that metal-based dentures, when fabricated using proper methods, do not promote alveolar ridge resorption.\u003c/p\u003e\n\u003ch3\u003eLimitations\u003c/h3\u003e\n\u003cp\u003eThis is a case report of a patient who has gone 28 years without visiting a dental clinic. This case report was conducted after the patient received detailed written and verbal explanations, written informed consent was obtained, and approval was obtained from the Ethics Committee of the School of Life Dentistry, Nippon Dental University.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eCompliance with ethical standards\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe ethical committee of Nippon Dental University approved the present study (NDU-T2024-56).\u003c/p\u003e\n\u003cp\u003eAs this study involves humans and human data, I declare that it complies with the Declaration of Helsinki.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent to publish\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe author has read and agreed to the published version of the manuscript.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthor\u0026rsquo;s contributions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eHA contributed to the study as the first author and wrote the manuscript, conception, design, acquisition, analysis, and interpretation of data.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConflicts\u0026nbsp;of interest\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe author reports no conflicts of interest related to the present study.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eWritten informed consent was obtained from the patient for her personal and clinical information and images to be published in this study.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n \u003cli\u003e\u003cspan\u003eJurado CA, Azpiazu-Flores FX, Fu C-C, Rojas-Rueda S, Guzman-Perez G, Floriani F. Expediting the rehabilitation of severely resorbed ridges using a combination of CAD-CAM and analog techniques: A case report. medicina 2024,60, 260; https://doi.org/10.3390/medicina60020260.\u003c/span\u003e\u003c/li\u003e\n \u003cli\u003e\u003cspan\u003ePham NQ, Gonda T, Maeda Y, Ikebe K. Average rate of ridge resorption in denture treatment: A Systematic Review. J Prosthodont. Res. 2021, 65, 429\u0026ndash;437.\u003c/span\u003e\u003c/li\u003e\n \u003cli\u003e\u003cspan\u003eKnezović-Zlatarić, D. Resorptive changes of maxillary and mandibular bone structures in removable denture wearers. Acta Stomatol Croat 2002, 36, 253\u0026ndash;259.\u003c/span\u003e\u003c/li\u003e\n \u003cli\u003e\u003cspan\u003eRavi R, Chaudhary N, Dahiya D. Complete denture fabrication and management of severely resorbed mandibular residual ridge in geriatric patient: A case report. EAS J Humanit Cult Stud, 2021. 3, 163\u0026ndash;167. DOI: 10.36349/easjhcs.2021.v03i04.004.\u003c/span\u003e\u003c/li\u003e\n \u003cli\u003e\u003cspan\u003eAtwood DA. Reduction of residual ridges: a major oral disease entity. J Prosthet Dent 1971; 26: 266\u0026ndash;279.\u003c/span\u003e\u003c/li\u003e\n \u003cli\u003e\u003cspan\u003eCarlsson GE. Clinical morbidity and sequelae of treatment with complete dentures. J Prosthet Dent 1998; 79: 17\u0026ndash;23.\u003c/span\u003e\u003c/li\u003e\n \u003cli\u003e\u003cspan\u003eXieQ, Narhi TO, Nevbalainen JM, Wolf J, Alnamo A. Oral status and prosthetic factors related to residual ridge resorption in elderly subjects. Acta Odontol Scand 1997; 55: 306\u0026ndash;313.\u003c/span\u003e\u003c/li\u003e\n \u003cli\u003e\u003cspan\u003eDe Baat, C., Kalk W, van\u0026apos;t Hof, M.A. Factors connected with alveolar bone resorption among institu-tionalized elderly people. Community Dent Oral Epidemiol 1993; 21: 317\u0026ndash;320.\u003c/span\u003e\u003c/li\u003e\n \u003cli\u003e\u003cspan\u003eKelly E. Changes caused by a mandibular removable partial denture opposing a maxillary complete denture. J Prosthet Dent 1972; 22: 140\u0026ndash;150.\u003c/span\u003e\u003c/li\u003e\n \u003cli\u003e\u003cspan\u003eAdams LP, Wilding RJ. A photogrammetric method for monitoring changes in the residual alveolar ridge form. J Oral Rehabil 1985;12:443\u0026ndash;450.\u003c/span\u003e\u003c/li\u003e\n \u003cli\u003e\u003cspan\u003eBelfiglio EJ.Using metal bases in making complete dentures. J Prosthet Dent 1987; 58: 314\u0026ndash;317.\u003c/span\u003e\u003c/li\u003e\n \u003cli\u003e\u003cspan\u003eWatt DM, MacGregor AR. Designing complete dentures. 2nd ed. Bristol, United Kingdom: Wright,1986. p.15\u0026ndash;23.\u003c/span\u003e\u003c/li\u003e\n \u003cli\u003e\u003cspan\u003ePo\u0026scaron;tić S. Influence of balanced occlusion in complete dentures on the decrease in the reduction of an edentulous ridge. Vojnosanit Pregl. 2012; 69: 1055\u0026ndash;1060.\u003c/span\u003e\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"bmc-oral-health","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"ohea","sideBox":"Learn more about [BMC Oral Health](http://bmcoralhealth.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/ohea/default.aspx","title":"BMC Oral Health","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"complete denture, ridge resorption, occlusal balance, metal-based denture, bilateral balanced occlusion","lastPublishedDoi":"10.21203/rs.3.rs-6458372/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6458372/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eBackground:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eDenture treatment is crucial for edentulous patients to maintain a long and healthy life, as well as restore their chewing function. After complete dentures are fitted, it is not uncommon for them to become ill-fitting due to ridge resorption over time, requiring adjustments or relining procedures. Residual ridge resorption results from the combined influence of various local and systemic factors. There have been no reported cases of patients who have worn complete dentures for an extended period without experiencing significant alveolar ridge resorption. I report a case of a patient who had not visited a dentist or had any adjustments for 28 years after being fitted with complete dentures.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCase presentation:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe patient, a 56-year-old woman, visited the general dentistry of the Nippon Dental University Hospital in Tokyo in March 1994. The diagnosis was masticatory dysfunction caused by ill-fitting upper and lower complete dentures. The treatment plan aimed to improve oral hygiene, restore the health of the alveolar ridge, and achieve proper occlusal contact with a final prosthetic device. The upper and lower dentures were fitted in May 1994. In November 2022, her artificial tooth broke, and she visited the clinic requesting denture repair for the first time in 28 years. A medical interview revealed that the patient had never visited another dental clinic since having dentures fitted 28 years ago. Although wear of the artificial teeth was observed, when the fitting condition of the upper and lower dentures was checked using fitting test materials, it was confirmed that there were no problems with the fitting condition and that there was almost no alveolar ridge resorption.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusion:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eI report on a patient who has worn the same dentures for 28 years. Although wear of the artificial teeth was observed due to bilateral balanced occlusion, the occlusal balance was appropriately maintained. It has been found that metal-based dentures, when fabricated using proper methods, do not promote alveolar ridge resorption.\u003c/p\u003e","manuscriptTitle":"A case report of a patient with metal-based complete dentures from a long-term follow-up perspective","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-07-14 10:43:25","doi":"10.21203/rs.3.rs-6458372/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2025-08-26T03:57:16+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-08-22T06:51:08+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"235589058631480798273120832997880642708","date":"2025-08-14T08:46:25+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-07-15T08:40:37+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-07-15T06:59:25+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"38487679947050922607472899314540263892","date":"2025-07-10T06:48:00+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-07-10T03:35:40+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"251233663245511818930850273783529941219","date":"2025-07-10T02:55:54+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"253281244464232916935279359975463070374","date":"2025-07-09T12:33:02+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-07-09T10:57:50+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-05-15T01:50:02+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2025-05-02T09:13:59+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-05-01T08:49:04+00:00","index":"","fulltext":""},{"type":"submitted","content":"BMC Oral Health","date":"2025-05-01T08:47:59+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"bmc-oral-health","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"ohea","sideBox":"Learn more about [BMC Oral Health](http://bmcoralhealth.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/ohea/default.aspx","title":"BMC Oral Health","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"cdab4e22-8129-4d64-a2f6-67f89a604d0e","owner":[],"postedDate":"July 14th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2025-11-24T16:00:35+00:00","versionOfRecord":{"articleIdentity":"rs-6458372","link":"https://doi.org/10.1186/s12903-025-07335-x","journal":{"identity":"bmc-oral-health","isVorOnly":false,"title":"BMC Oral Health"},"publishedOn":"2025-11-21 15:57:17","publishedOnDateReadable":"November 21st, 2025"},"versionCreatedAt":"2025-07-14 10:43:25","video":"","vorDoi":"10.1186/s12903-025-07335-x","vorDoiUrl":"https://doi.org/10.1186/s12903-025-07335-x","workflowStages":[]},"version":"v1","identity":"rs-6458372","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-6458372","identity":"rs-6458372","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}