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Purpose: To compare the peri-implant bone loss of mandibular complete-arch implant-supported fixed prostheses (FPSs) supported by three and four implants and to correlate with the size of the horizontal and vertical distal cantilever at prosthesis placement (T1) and after 1 year (T2). Materials and Methods: A total of 72 external hexagon (EH) type implants were placed in 20 participants. Of these, 24 supported an FPS with three implants (G3I) and 48 with four implants (G4I). The mandibular implants were named 1, 2, 3, and 4 according to their location in the arch, in a clockwise direction. Digital periapical radiographs were taken at times T1 and T2 for analysis and measurement of peri-implant bone loss. The horizontal and vertical distal cantilevers were measured with a digital caliper and correlated with peri-implant bone loss. Results: The survival rate of implants in G3I was 91.66%, and in G4I it was 97.91%. The mean bone loss in G3I was 0.88 ± 0.89 mm, and in G4I it was 0.58 ± 0.78 mm (P = .225). There was no correlation between distal horizontal cantilevers and bone loss in the studied groups, with G3I being -0.25 (P = .197) and G4I -0.22 (P = .129). Larger vertical cantilevers of implants 1 (P = .018), 3 (P =.015), and 4 (P = .045) correlated with greater bone loss in G4I. Conclusions: The number of implants in an FPS did not influence peri-implant bone loss after 1 year of follow-up. Larger vertical cantilevers influenced greater bone loss in complete-arch implant-supported fixed prostheses supported by four implants. [ABSTRACT FROM AUTHOR]

Bone graft materials are often used in implant treatment to optimize functional and esthetic outcomes. The requirements for bone grafting materials are the ability to maintain space for bone regeneration to occur and the capability of being resorbed by osteoclasts and replaced with new bone tissue occurring in passive chemolysis and bone remodeling. Carbonate apatite (CO3Ap) granules (Cytrans Granules, GC) are a chemically synthetic bone graft material similar to autogenous bone minerals and more biocompatible than allografts and xenografts. The aim of this report is to evaluate the efficacy of CO3Ap granules in implant treatments when used alone or in combination with autogenous bone. The clinical findings and the radiographic and histologic assessments in three cases of immediate implant placement and lateral and vertical guided bone regeneration are reported. Despite the short-term follow-ups, histologic findings showed that CO3Ap granules were efficiently resorbed and replaced bone in clinical use. Furthermore, the clinical findings showed that CO3Ap granules maintained their morphology around the implant. This limited short-term case report suggests that this bone substitute is effective. However, further clinical studies and long-term reports of this new biomaterial are needed. [ABSTRACT FROM AUTHOR]

Objective: Ideal implant placement in atrophied posterior mandibular regions is challenging due to surgical difficulties and anatomical limitations. This study aimed to evaluate the use of allogeneic bone rings for vertical augmentation of atrophied posterior mandibular regions with simultaneous implants compared to autogenous bone rings, while avoiding donor site morbidity. Method and materials: A total of 24 vertically atrophied posterior mandibular segments (in 14 patients) were equally randomized into a study group in which mineralized freeze-dried allogeneic bone rings were used, and a control group in which autogenous bone rings with prepared implant osteotomies were harvested from the chin and used. All augmentation sites were prepared before inserting the bone rings. Implants were simultaneously inserted, fixing the bone rings into the native bone. All patients were clinically assessed after 1 week, 2 weeks, and 1 month. Crestal bone level was radiographically assessed after lweek, 6 months, and 3 months of prosthetic loading. Results: None of the 24 bone rings showed signs of implant or graft failure. There was no significant difference in the crestal bone level between the groups. Conclusion: Allogeneic bone rings can be a viable alternative to autogenous bone rings in augmenting the posterior aspect of the mandible, mitigating the concerns associated with donor site complications. [ABSTRACT FROM AUTHOR]

Purpose: To assess whether a recently introduced implant placement micromotor that provides site-specific, operatorindependent cancellous bone density measurements can detect the presence of a cortical bone layer and measure its thickness and density. Materials and Methods: An in vitro experiment was performed on six double-layer polyurethane foam blocks mimicking the jawbone with different cortical thickness/cancellous density combinations. The densities were measured using the micromotor after either removing the cortical layer or leaving it intact, both with and without irrigation. Results: The results were compared by means of nonparametric statistical tests. Independent of irrigation, the micromotor detected the cortical layer when it was left intact and accurately estimated its thickness. The micromotor did not discriminate between blocks when they were considered separately, but it did when they were grouped into four or three classes. Conclusions: The present study suggests that the micromotor may represent a valid device to quantitatively assess bone quality and density. If the micromotor can quantitatively distinguish different cortical/cancellous bone combinations in humans, it may be a helpful tool for performing finely tuned, patient-tailored preparations of the implant seat, making tooth rehabilitation in challenging clinical conditions more predictable. [ABSTRACT FROM AUTHOR]

Guided bone regeneration (GBR) requires a tension-free flap without damaging the collateral circulation in order to secure better surgical outcomes. Topographic knowledge regarding the neurovascular bundles in the posterior aspect of the mandible can prevent complications during lingual flap design. The lingual branch (LB) of the inferior alveolar or maxillary arteries is not sufficiently illustrated or described in the literature. Nevertheless, it has an intimate relationship with the lingual nerve (LN) during ridge augmentation and implant-related posterior mandible surgery. Therefore, this study aimed to clarify the morphology and topography of the LB related to GBR surgeries. In the present human cadaveric study, the LB was analyzed in 12 hemimandibles using latex injection and corrosion casting. Two types of LB were identified based on their origin and course. The LB was found in a common connective tissue sheath close to the LN. The LB assembled several anastomoses on the posterior lingual aspect of the mandible and retromolar area. The LB acted as an anatomical landmark in identifying LN at the posterior lingual aspect of the mandible. [ABSTRACT FROM AUTHOR]

The anterior mandible is the most challenging anatomical site for performing periodontal plastic surgeries. Increased demands for optimal root coverage and esthetic outcomes contribute to the development of pedicle flap-based surgical solutions, in contrast to the predominantly used free gingival graft. The aims of this study were to (1) summarize the current literature to identify the most-used techniques, indications, and their efficacy, and (2) provide a decision table for surgeons to navigate through the selection of appropriate techniques. Four main approaches were identified: free gingival graft, lateral sliding, tunneling, and coronally advanced flap. The flap approaches are mostly combined with a connective tissue graft. The decision table considers the patient's chief complaint, local anatomical factors, and technique sensitivity. The table provides a framework for supporting an evidence-based selection of surgical techniques and for studying novel methods to achieve predictable root coverage in the anterior mandible. [ABSTRACT FROM AUTHOR]

This assessment evaluated the clinical feasibility of using narrow-diameter implants to support a mandibular overdenture. Twelve patients presenting with an edentulous mandible were recruited from nine dental offices. Each patient received two to four implants in the mandible. The implants were placed without additional bone augmentation, and a total of 36 implants were placed. All sites achieved satisfactory crestal bone stability and soft tissue maintenance 1 year after the final prosthetic restoration. This investigation was supported by the Osseointegration Foundation, working in conjunction with the Zest Anchors implant company. There are three basic valuable activities that emerge from a professional foundation, which were reflected in this case study. They include disseminating information to practitioners, persuading young clinicians to become research investigators, and reaching out to patients in need of treatment who cannot afford it without a charitable opportunity. [ABSTRACT FROM AUTHOR]

Purpose: The objective of the present systematic review and meta-analysis was to assess randomised controlled trials (RCTs) which assessed the efficacy of mini dental implants (MDIs) and standard-diameter implants (SDIs) in retaining mandibular overdentures (MO). Materials and Methods: The focused question was “Is there a difference in the mechanical stability between MDIs and SDIs in retaining MO?” Indexed databases were searched up to and including November 2023 using different keywords. Boolean operators were used during the search. The literature was searched in accordance with the PRISMA guidelines. The PICO characteristics were: patients (P) = individuals with complete mandibular dentures requiring dental implants; Intervention (I) = placement of MDIs under mandibular dentures; Control (C) = placement of SDIs under mandibular dentures; Outcome (O) = comparison of stability between MDIs and SDIs in supporting mandibular dentures. Only RCTs were included. Risk of bias (RoB) was assessed using the Cochrane RoB tool. Results: Five RCTs were included. The numbers of participants ranged between 45 and 120 edentulous individuals wearing complete mandibular dentures. The mean age of patients ranged between 59.5 ± 8.5 and 68.3 ± 8.5 years. The number of MDIs and SDIs ranged between 22 and 152 and 10 and 80 implants, respectively. The follow-up duration ranged between one week and 12 months. Three RCTs reported an improvement in the quality of life (QoL) of all patients after stabilisation of mandibular dentures using MDIs or SDIs. In one RCT, peri-implant soft tissue profiles were comparable between MDIs and SDIs at the 1-year follow-up. The implant survival rate was reported in two RCTs, which were from 89% to 98% and 99% to 100% for MDIs and SDIs, respectively. All RCTs had a low RoB. Conclusion: Mini dental implants represent a viable alternative to traditional standard-diameter implants when seeking optimal retention for mandibular overdentures. [ABSTRACT FROM AUTHOR]

The purpose of the present study was to describe a novel protocol for a minimally invasive pocket elimination surgery (MI-PES) in the posterior maxilla and mandible, which consists of the combined use of (1) an access flap based on an internally beveled gingivectomy with minimal to no papilla mobilization at the buccal aspect, and (2) a resective procedure with an apically positioned flap on the lingual aspect. The interproximal bone defects were accessed with a single (lingual) flap, and the bone architecture was modified by the adoption of piezoelectric inserts for controlled bone recontouring associated with fiber retention. Mean probing depth (PD) was 5.5 ± 0.8 mm before surgery and 2.7 ± 0.6 mm at the 6-month reevaluation. All treated pockets showed a postsurgical PD < 4 mm. Gingival recession (REC) was 0.3 ± 0.5 mm at baseline and increased to 1.6 ± 0.8 mm at 6 months. When buccal and lingual pockets were analyzed separately, a trend toward a similar PD reduction, less REC increase, and greater clinical attachment level gain was recorded for buccal pockets. These preliminary observations seem to support the use of MI-PES as a valuable option for pocket elimination, at least when residual pockets are associated with a shallow interproximal osseous crater in the posterior maxilla or mandible. [ABSTRACT FROM AUTHOR]

Tooth autotransplantation is an effective treatment to replace missing teeth. Digital planning can facilitate successful autotransplantation. Guiding templates are highly recommended when performing cases in healed ridges in the posterior area to reduce excessive bone loss and increase the chances of fitting the donor tooth in the new socket. This case report highlights the use of 3D planning tools and fully guided drilling templates for successful tooth autotransplantation in the posterior area. Two tooth autotransplantations were performed in a 51-year-old patient using mandibular third molars to replace hopeless mandibular first and second molars. Root canal treatments were carried out before the surgeries, and different alveoloplasty techniques were used in each recipient area. The prosthetic phase was carried out after 9 months. Both teeth were asymptomatic, functional, and exhibited no signs of resorption or apical radiolucency and showed complete regeneration of the periodontal apparatus at the 2-year follow-up. [ABSTRACT FROM AUTHOR]

Rationale: Oral appliances are second-line treatments after continuous positive airway pressure for obstructive sleep apnea (OSA) management. However, the need for oral appliance titration limits their use as a result of monitoring challenges to assess the treatment effect on OSA. Objectives: To assess the validity of mandibular jaw movement (MJM) automated analysis compared with polysomnography (PSG) and polygraphy (PG) in evaluating the effect of oral appliance treatment and the effectiveness of MJM monitoring for oral appliance titration at home in patients with OSA. Methods: This observational, prospective study included 135 patients with OSA eligible for oral appliance therapy. The primary outcome was the apnea-hypopnea index (AHI), measured through in-laboratory PSG/PG and MJM-based technology. Additionally, MJM monitoring at home was conducted at regular intervals during the titration process. The agreement between PSG/PG and MJM automated analysis was revaluated using Bland-Altman analysis. Changes in AHI during the home-based oral appliance titration process were evaluated using a generalized linear mixed model and a generalized estimating equation model. Results: The automated MJM analysis demonstrated strong agreement with PG in assessing AHI at the end of titration, with a median bias of 0.24/h (limits of agreement, -11.2 to 12.8/h). The improvement of AHI from baseline in response to oral appliance treatment was consistent across three evaluation conditions: in-laboratory PG (-59.6%; 95% confidence interval, -59.8% to -59.5%), in-laboratory automated MJM analysis (-59.2%; -65.2% to -52.2%), and at-home automated MJM analysis (-59.7%; -67.4% to -50.2%). Conclusions: Incorporating MJM automated analysis into the oral appliance titration process has the potential to optimize oral appliance therapy outcomes for OSA.

Purpose: To compare the standard 360-degree CBCT acquisition protocol to the low dose 180-degree CBCT protocol for implant planning. Materials and Methods: Two groups of patients, each consisting of 35 patients, were included in the study. The first group was imaged with the conventional 360-degree CBCT protocol, and the second group was imaged with the low dose 180-degree CBCT protocol. The primary outcome of this study was the number of scans that needed to be repeated due to poor image quality. In addition, six secondary parameters were evaluated quantitatively and qualitatively. Results: The results showed that there was no need to repeat any of the CBCT scans that were obtained in either group, which showed that 360-degree and 180-degree protocols had comparable image quality. As for the secondary parameters, the results showed that the evaluators were able to evaluate the six chosen parameters in a comparable manner. Conclusions: The 180-degree low dose CBCT scan is a viable option for dental implant treatment planning in the posterior mandible as it provides comparable and adequate information regarding accuracy of measurements, identification of critical structures, evaluation of bone quality, and any pathology. [ABSTRACT FROM AUTHOR]

Over the past two decades, the Khoury plate technique has been widely utilized with much success to facilitate bone augmentation in critically deficient bone areas. Simply, the technique includes harvesting autogenous bone plates and utilizing them with external screw fixation. The rigidity of the bone plates enclosing the bony defect on both the buccal and lingual surfaces allows for tension-free bone remodeling to occur, favoring an ideal bone-forming environment. Following, a 4- to 6-month healing period, a flap is raised, screws may be removed, and implants are placed. With advancements made in tissue engineering, a novel mineral-organic resorbable bone adhesive (MORBA) formulated from underwater biomimetic marine proteins has recently been utilized for immediate bone-to-bone or bone-to-metal fixation. MORBA is a synthetic, injectable, self-setting, and resorbable load-bearing adhesive biomaterial that exhibits over 300 pounds of fixation strength. The unique adhesive properties of MORBA enable it to immediately stabilize dental implants into host bone. The present article describes a novel modification of the Khoury plate technique that utilizes MORBA as a substitute for screws during bone plate fixation. A step-by-step protocol is described that utilizes this novel biomaterial, favoring a more biologic approach to this conventional technique. This novel modification is surgically easier to conduct and is a more biocompatible option that avoids screw fixation and removal. [ABSTRACT FROM AUTHOR]

Recurrent benign gingival lesions occurring in the anterior dentition are clinical dilemmas. While complete removal of such lesions is required to prevent recurrence, this can result in a poor esthetic outcome. Relative to this conundrum, this report discusses the diagnosis, psychologic management, and clinical treatment of two patients with recurring lesions on the facial gingiva of the mandibular and maxillary incisors, respectively. Patient A, a 55-year-old woman, presented with a recurrent peripheral ossifying fibroma (POF); Patient B, a 76-year-old man, presented with a recurrent pyogenic granuloma (PG). Both patients underwent multiple procedures and were ultimately treated without lesion recurrence. The efficacious surgical treatment of recurrent gingival lesions like POF and PG requires an aggressive approach involving lesion removal of the lesion as well as a 1.0- to 2.0-mm margin of normal tissue, underlying alveolar bone, and associated periodontal ligament (PDL). The rationale for this approach stresses the potential periodontal and esthetic ramifications that were considered. In summary, when recurrent benign gingival lesions are localized to the anterior part of the mouth, the approach to their surgical removal should be modified to minimize the extent of gingival recession and other potential esthetic issues. [ABSTRACT FROM AUTHOR]

The Custom Alveolar Ridge Splitting (CARS) technique was recently reported as a less-invasive treatment option for augmentation of the maxillary anterior area in cases where alveolar width deficiency exists due to bone resorption and remodeling. This technique creates an intraosseous defect to improve success when horizontal ridge augmentation is attempted. The purpose of the present case report was to demonstrate implant placement in an atrophic posterior mandibular site using the CARS technique. This technique was used in the mandibular right second premolar area, followed by placement of a single implant. The restored implant showed stable soft and hard tissue outcomes at 6 months postloading. [ABSTRACT FROM AUTHOR]

Ontocetus is one of the most notable extinct odobenines owing to its global distribution in the Northern Hemisphere. Originating in the Late Miocene of the western North Pacific, this lineage quickly spread to the Atlantic Ocean during the Pliocene, with notable occurrences in England, Belgium, The Netherlands, Morocco and the eastern seaboard of the United States. Reassessment of a pair of mandibles from the Lower Pleistocene of Norwich (United Kingdom) and a mandible from the Upper Pliocene of Antwerp (Belgium) that were referred to as Ontocetus emmonsi reveals existences of features of both Ontocetus and Odobenus. The presence of four post-canine teeth, a lower canine larger than the cheek-teeth and a lower incisor confirms the assignment to Ontocetus; simultaneously, characteristics such as a fused and short mandibular symphysis, a well-curved mandibular arch and thin septa between teeth align with traits usually found in Odobenus. Based on a combination of these characters, we describe Ontocetus posti, sp. nov. Its mandibular anatomy suggests, a better adaptation to suction-feeding than what was previously described in the genus suggesting that Ontocetus posti sp. nov. likely occupied a similar ecological niche to the extant walrus Odobenus rosmarus. Originating from the North Pacific Ocean, Ontocetus most likely dispersed via the Central American Seaway. Although initially discovered in the Lower Pliocene deposits of the western North Atlantic, Ontocetus also left its imprint in the North Sea basin and Moroccan Plio-Pleistocene deposits. The closure of the Isthmus of Panama during the Mio-Pliocene boundary significantly impacted the contemporary climate, inducing global cooling. This event constrained Ontocetus posti in the North Sea basin leaving the taxon unable to endure the abrupt climate changes of the Early Pleistocene, ultimately going extinct before the arrival of the extant counterpart, Odobenus rosmarus.

INTRODUCTION: The primary objective of this retrospective study was to document the normal variation of clinical mobility of the mandibular symphysis in cats and possible associations with bodyweight, age, sex, sexual status, breed and skull morphology. Secondarily, the radiographic appearance of the mandibular symphysis and possible associations with the analyzed data were evaluated. MATERIALS AND METHODS: Two hundred and sixteen cats of 15 different breeds that underwent maxillofacial, oral and dental procedures from April 2015 to December 2021 were included. Clinical mobility was evaluated under general anesthesia using a 0 to 3 scale in lateromedial (LM) and dorsoventral (DV) directions. The symphysis was radiographically classified on the occlusal radiographic view of the rostral mandibles as fused or open, and with parallel or divergent margins. RESULTS: Bodyweight ranged from 2.2 to 12.5 kg (median 4.0 kg), age from 4 months to 17 years and 4 months (median 6 years and 4 months). At the first evaluation DV symphyseal mobility was 0 in 177 cases (82%), 1 in 32 cases (14.8%) and 2 in 7 cases (3.2%), LM mobility was 0 in 61 cases (28.3%), 1 in 110 cases (50.9%) and 2 in 45 cases (20.8%). 81.1% of the radiographs were included in the statistical analysis. Three symphyses (1.6%) were classified as fused and 190 (98.4%) as open, 129 (68.8%) having divergent margins and 61 (31.6%) parallel. One hundred and forty-eight cases (76.7%) did not show the presence of odontoclastic replacement resorption on the canine teeth (TR subgroup 1), 23 (11.9%) showed stage ≤3 lesions (TR subgroup 2) and 22 (11.4%) stage 4 lesions (TR subgroup 3). Logistic regression models exploring factors that affected DV and LM mobility were statistically significant (p

The diversity of vertebrate skeletons is often attributed to adaptations to distinct ecological factors such as diet, locomotion, and sensory environment. Although the adaptive evolution of skull, appendicular skeleton, and vertebral column is well studied in vertebrates, comprehensive investigations of all skeletal components simultaneously are rarely performed. Consequently, we know little of how modes of evolution differ among skeletal components. Here, we tested if ecological and phylogenetic effects led to distinct modes of evolution among the cranial, appendicular and vertebral regions in extant carnivoran skeletons. Using multivariate evolutionary models, we found mosaic evolution in which only the mandible, hindlimb and posterior (i.e. last thoracic and lumbar) vertebrae showed evidence of adaptation towards ecological regimes whereas the remaining skeletal components reflect clade-specific evolutionary shifts. We hypothesize that the decoupled evolution of individual skeletal components may have led to the origination of distinct adaptive zones and morphologies among extant carnivoran families that reflect phylogenetic hierarchies. Overall, our work highlights the importance of examining multiple skeletal components simultaneously in ecomorphological analyses. Ongoing work integrating the fossil and palaeoenvironmental record will further clarify deep-time drivers that govern the carnivoran diversity we see today and reveal the complexity of evolutionary processes in multicomponent systems.

Objectives: Work in animal models has implicated excessive occlusal forces and occlusal trauma as co-destructive factors for periodontitis. The main aim of the present study was to make a radiographic assessment of the effects of excessive occlusal forces, ie occlusal/incisal tooth wear, widening of the periodontal space, and the presence of a mandibular torus, on interproximal marginal bone loss in a large series of patients. A secondary aim was to evaluate the statistical correlation between the parameters in two specific teeth and those of 12 teeth for marginal bone loss and six teeth for occlusal/incisal tooth wear within the same individual. Method and materials: A total of 1,950 full-mouth radiographic surveys were analyzed retrospectively. Interproximal marginal bone loss was quantified relative to the root length (Schei ruler technique). In addition, occlusal/incisal tooth wear and periodontal ligament space widening of the periodontal space were assessed, as well as the presence of a mandibular torus. Odds ratio and logistic regression analysis were used to determine the association between occlusal trauma and marginal bone loss. Results: The correlation of the measured parameters between the values for specific teeth and the whole dentition was evaluated from data from the first 400 radiographs. Teeth 41 and 33 showed the best correlation to the whole dentition: 0.85 for interproximal marginal bone loss, 0.83 for widening of the periodontal space, and 0.97 forocclusal/incisal tooth wear. The results of a logistic regression analysis with age as an independent variable, revealed a significant association between bone loss and both tooth wear (odds ratio = 2.767) and bone loss and widening of the periodontal space (odds ratio = 2.585). Conclusion: Tooth wear was positively correlated to both widening of the periodontal space and marginal bone loss. No correlation was found between the presence of a mandibular torus and marginal bone loss. [ABSTRACT FROM AUTHOR]

Dentinogenic ghost cell tumor (DGCT) is an uncommon odontogenic tumor considered to be the solid, tumorous variant of calcifying odontogenic cyst. DGCT is characterized by islands of ameloblastoma-like epithelial cells that resemble the enamel organ, the presence of ghost cells, and dentinoid material. This article reports a rare case of dentinogenic ghost cell tumor as sociated with an odontoma in an adult patient, with a review of the literature. To the best of the authors' knowledge, there have only been four case reports of DGCT associated with odontoma, all of which occurred in children and adults younger than 30 years old. [ABSTRACT FROM AUTHOR]

Purpose: To assess the implant survival rate in mandibles reconstructed with free fibula flap after oral tumor resection after 1 year of prosthetic loading. A secondary objective was to compare immediate or delayed implant placement protocols in this population. Materials and Methods: Electronic and manual searches were performed on different databases for controlled and prospective trials that indicated implant survival rate. This systematic review followed PRISMA guidelines. Risk of bias was evaluated using Cochrane Collaboration tools. Meta-analyses heterogeneity source assessment and GRADE evaluation were performed among studies with identical follow-ups. Results: Among 305 primarily selected articles, 109 were eligible after reading the title and abstract, and 8 were included after full-text reading: 2 randomized controlled trials and 6 prospective studies comprising 140 patients and 507 implants. Meta-analyses estimated an overall survival rate of 97% (95% CI: 94% to 99%) after 1 year of prosthetic loading. The survival rate was 98% (95% CI: 94% to 100%) with immediate implantation and 97% (95% CI: 90% to 99%) with delayed implantation. Only 3 studies reported radiotherapy treatment, with no real impact on implant survival rate. Overall, 69% of tumors were benign. Conclusions: Implant placement in vascularized fibula flaps in the mandible is recommended for patients undergoing segmental mandibular reconstruction after tumor resection. Within the limitations of this study, no significant difference in survival rates was found between immediate and delayed implant placement. [ABSTRACT FROM AUTHOR]

Horizontal and vertical ridge augmentation via the bone shell technique provides predictable outcomes. The external oblique ridge is the most-used donor site for bone plate harvesting, followed by the mandibular symphysis. The lateral sinus wall and the palate have also been described as alternative donor sites. This preliminary case series reports a bone shell technique that used the coronal segment of the knife-edge ridge as a bone shell in five consecutive edentulous patients (20 sites) with severe mandibular horizontal ridge atrophy and adequate ridge height. The follow-up period was 1 to 4 years. The average horizontal bone gains at 1 mm and 5 mm below the newly formed ridge crest were 3.6 ± 0.76 mm and 3.4 ± 0.92 mm, respectively. Ridge volume was sufficiently restored in all patients to enable implant placement in a staged approach. In 2 of the 20 sites, additional hard tissue grafts were required at implant placement. The advantages of utilizing the relocated crestal ridge segment are as follows: The donor and recipient sites are the same, no major anatomical structures are compromised, periosteal releasing incisions and flap advancement are not required for primary wound closure, and the risk of wound dehiscence is minimized due to reduced muscle tension. [ABSTRACT FROM AUTHOR]

Purpose: To assess the literature comparing histologic levels of osseointegration for titanium vs zirconia dental implants. Materials and Methods: This systematic review was conducted following the PRISMA guidelines and was registered in PROSPERO (CRD42021236781). Electronic and manual searches were carried out through the PubMed/MEDLINE, PubMed Central, and Embase databases with a platform-specific search strategy combining controlled terms (MeSH and Emtree) and text words. The articles were selected by two independent investigators who evaluated the articles based on the criteria for eligibility. Results: A total of 17 articles were included. All were preclinical studies. The populations included dogs (27.55%), minipigs (14.28%), rats (14.28%), and rabbits (43.89%); and the implantation site varied among the mandible (36.82%), maxilla (9.04%), tibia (17.64%), skull (10.70%), and femur (25.80%). A total of 370 titanium (Ti) implants and 537 zirconia (Zr) implants were evaluated. The average osseointegration (% bone-to-implant contact) for Zr was 55.51% (17.6% to 89.09%), and for Ti was 58.50% (23.2% to 87.85%). There was no statistical difference between studies at the 2-month follow-up (P = .672), but this difference was significant at 1 and 3 months (P < .001). Conclusions: Within the limitations of this review, Zr implants had a similar level of osseointegration compared to Ti implants. Nonetheless, because these findings are based on preclinical research, all data must be carefully examined. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the gain in peri-implant keratinized mucosa (KM) using a combination of a free gingival graft (FGG) strip with a xenogeneic collagen matrix (XCM) and compare it to that of an FGG alone. Materials and Methods: This randomized controlled clinical study included a total of 30 patients with a minimal amount of peri-implant KM (= 1 mm) in the maxillary and mandibular anterior regions (including the premolars). The study population was divided into two groups using a randomization protocol; group A (n = 15) received a combination of FGG strip and XCM, and group B (n = 15) received FGG only to augment the KM. Clinical parameters included width of KM (WKM) measured at baseline, 1 month, and 6 months; a customized pink esthetic score (PES) measured at baseline and 6 months; and patient morbidity using visual analog scale (VAS) at days 1, 7, and 14 postoperatively. Results: After 1 month, both groups showed statistically significant gain in KM that reduced slightly by the 6-month follow-up but remained statistically significant when compared to baseline. When the gain was compared between the two groups, the difference was not statistically significant. Better esthetic outcomes and lower morbidity were reported in group A compared to group B, and this difference was statistically significant. Conclusions: Within the limitations of the study, it can be concluded that the combination of FGG strip with XCM is a viable alternative to the use of FGG in augmenting peri-implant KM. [ABSTRACT FROM AUTHOR]

Peri-implantitis is an inflammatory condition that involves the loss of attachment and support around dental implants. In this case report, a middle-aged woman presented with two implants in the mandibular right quadrant that were diagnosed with peri-implantitis. The patient also had tenderness around the implants and reported sensitivity when performing oral hygiene procedures. Surgical treatment comprised a free gingival graft to augment the keratinized tissue width around the implants, followed by a second procedure of implantoplasty and surface decontamination. The outcome showed radiographic resolution of the peri-implant defect around the premolar implant with a marked increase of keratinized tissue (> 4 mm) around both implants after 1 year of follow up. On a patient level, significantly reduced sensitivity around the implants and better home care were reported. This case report showed that the increase of keratinized tissue may benefit the clinical and patient outcomes of periimplantitis treatment in terms of decreased probing depths, absence of inflammation, and improved radiographic crestal stability. The combined correction of both hard and soft tissue defects around peri-implantitis lesions may facilitate treatment success and help maintain peri-implant stability. [ABSTRACT FROM AUTHOR]

Background: Mandibular malpositioning may result in an abnormal concentration of stresses within the temporomandibular joint (TMJ) in adult rats, which may further lead to a series of pathological changes, such as articular cartilage wear, subchondral bone sclerosis and osteophyte formation. However, the pathological and adaptive changes in condylar cartilage caused by different stress distributions are still controversial. Objective: The aim of this study was to observe the effect of sagittal changes in mandibular position on condylar cartilage by changing the occlusal vertical dimension (OVD) in adult rats. Methods: Fifteen‐week‐old female rats were divided into three groups: control (CON), increased OVD (iOVD) and loss of occlusion (LO) groups. An occlusal plate and tooth extraction were used to establish the animal model. TMJ samples of the experimental and CON groups were observed and investigated by bone morphological, histomorphological and immunohistochemical staining analyses at 3 days, 1 week, 2 weeks, 4 weeks and 8 weeks. Weight curves were plotted. Results: Micro‐computed tomography showed that, compared with the CON group, cartilage destruction followed by repair occurred in both experimental groups, which was similar to the trend observed in haematoxylin‐eosin staining. All experimental results for the iOVD group showed an approximately similar time trend. Compared with the iOVD group, the toluidine blue and immunohistochemical staining results in the LO group showed no obvious change trend over time. Conclusion: Compared with occlusal loss, an increase in OVD caused faster and more severe damage to condylar cartilage, and subchondral bone repair occurred later. [ABSTRACT FROM AUTHOR]

Background: Contemporary fixed orthodontic appliances are shifting from non‐customized pre‐adjusted appliances to custom‐designed and printed appliances with novel digital setup systems. We are one step closer to precision dentistry and orthodontics using personalized mechanics and custom appliances. However, despite the evidential enhancement and other improvements to fixed appliances, tooth movement is still limited to five degrees of freedom. Opening or closing spaces still requires manually placing elastomeric chains or coil springs. Aim: In this article, we aimed to demonstrate how advancements in CAD/CAM technology, reverse engineering, and digital customization are helping orthodontics constantly evolve, enabling treatment with enhanced esthetics and minimal compliance. The clinical system (InBrace®, Irvine, CA) described in this article uses a patient‐specific, digitally designed multiloop NITI wire that delivers friction‐free, light, and continuous forces and activates automatically whenever the malocclusion deviates from the digital setup. Conclusion: Through digital customization, InBrace allows for automated tooth movement in all six degrees of freedom, including space opening or closure, via programmed non‐sliding mechanics. Clinical Significance: Precision orthodontics and personalized treatment have been significant developments in orthodontics recently. This article focuses on how a technologically advanced lingual appliance system could achieve targeted cosmetic results methodically via automation and personalization. [ABSTRACT FROM AUTHOR]

Aim: To investigate the effects of high‐intensity interval training (HIIT) on periodontitis (PD) progression and behavioural outcomes. Materials and Methods: Forty‐eight Wistar rats were divided into four groups: non‐trained (NT); non‐trained with PD; HIIT with PD; and HIIT. The HIIT protocol, involving daily treadmill sessions, spanned 8 weeks, with PD induced by ligature after the 6th week. Behavioural tests were conducted to assess anxiety and memory. Post euthanasia, we evaluated the systemic inflammatory profile and oxidative stress markers in the hippocampus and amygdala. A morphological evaluation and elemental composition analysis of the mandibular alveolar bone were performed. Results: PD exacerbated alveolar bone level, bone surface damage and alterations in calcium and phosphorus percentages on the bone surface (p <.05), while HIIT attenuated these changes (p <.05). HIIT improved systemic inflammatory markers altered by PD (tumour necrosis factor [TNF]‐α, interleukin [IL]‐10, TNF‐α/IL‐10 and IL‐1β/IL‐10 ratios, p <.05). PD animals exhibited lower total antioxidant capacity and levels of thiobarbituric acid reactive substances in the amygdala and hippocampus, respectively (p <.05). HIIT maintained these parameters at levels similar to those in NT animals. HIIT improved anxiety and memory outcomes altered by PD (p <.05). Conclusions: HIIT attenuates systemic inflammation, anxiety and memory outcomes promoted by PD. [ABSTRACT FROM AUTHOR]

In this study we tested classification performance of a sex estimation method from the mandible originally developed by Sella-Tunis et al. (2017) on a heterogeneous Israeli population. Mandibular linear dimensions were measured on 60 CT scans derived from the Czech living population. Classification performance of Israeli discriminant functions (DFs-IL) was analyzed in comparison with calculated Czech discriminant functions (DFs-CZ) while different posterior probability thresholds (currently discussed in the forensic literature) were employed. Our results comprehensively illustrate sensitivity of different discriminant functions to population differences in body size and degree of sexual dimorphism. We demonstrate that the error rate may be biased when presented per posterior probability threshold. DF-IL 1 showed least sensitivity to population origin and fulfilled criteria of sufficient classification performance when applied on the Czech sample with a minimum posterior probability threshold of 0.88 reaching overall accuracy ≥ 95%, zero sex bias, and 80% of classified individuals. The last parameter was higher in DF-CZ 1 which was the main difference between those two DFs suggesting relatively low dependance on population origin. As the use of population-specific methods is often prevented by complicated assessment of population origin, DF-IL 1 is a candidate for a sufficiently robust method that could be reliably applied outside the reference sample, and thus, its classification performance deserves further testing on more population samples. [ABSTRACT FROM AUTHOR]

Cemento-osseous dysplasia (COD) is classified, by the World Health Organization as a benign fibro-osseous lesion related to the tooth and periapical area of the jaws and is considered as a benign reactive process appearing from the apical periodontium in close relation with the apices of teeth. Usually, it is asymptomatic, discovered accidentally, and affecting particularly middle-aged African women. There are four subtypes distinguished of the lesion: periapical (PCOD), focal (FCOD), florid (FLCOD) and familial florid cementoosseous dysplasia (FFLCOD). Pseudocysts found in the jaws go by various names, including solitary bone cyst, traumatic bone cyst, or simple bone cyst (SBC). These two pathologies have been reported separately; however, their co-occurrence remains rare and the first case of FLCOD with co-occurrence of SBC was reported by Melrose et al. in 1976 and later a few cases been reported in the literature. The aim of this report is to describe a case of a 46- year-old oriental female diagnosed with FLCOD with co-occurrence of SBC. Under local analgesia, a surgical exploration of the cyst was performed. In addition, a biopsy with a trephine was done in the region of missing right first mandibular molar. Based on the patient clinical, radiographic, and histological findings, a diagnosis of FLCOD was made in cooccurrence with a mandibular SBC. An examination of another female family member unveils a distinctive case, and the familial factor has been ruled out. No further treatment was planned and only follow-up was suggested. [ABSTRACT FROM AUTHOR]

This double-blind, randomised clinical trial aimed to find out whether there is a difference in the prevalence of neurosensory disturbance (NSD) between patients who received 2% lidocaine and those who received 4% articaine during inferior alveolar nerve blocks (IANBs). Patients who underwent third molar extraction were randomised into two groups. IANB was performed using 2% lidocaine in Group 1 and 4% articaine in Group 2. The occurrence of NSD was documented. Patients were visited within 48 hours and one week after the tooth was removed. The type of anaesthetic drug (4% articaine versus 2% lidocaine) was the study's predictive factor. A total of 2400 patients were studied in two groups (1200 in each group). The mean (range) age of the patients was 28.40 (18–44) years. Five patients (0.41%) in the lidocaine group and seven (0.58%) in the articaine group had NSD after injection (p = 0.77). The prevalence of NSD after IANB was no higher in the articaine group than in the lidocaine group. [ABSTRACT FROM AUTHOR]

Osteoblastoma is a benign bone tumor with predominance in those < 20 years of age and rarely occurs in the maxillofacial region. The identification of FOS gene rearrangements in osteoblastomas has been reported, however, a small subset of osteoblastomas do not show FOS gene rearrangements. There are no reports discussing the relationship between age and FOS gene rearrangement in osteoblastomas. We report the case of a 66-year-old female patient with histological features of osteoblastoma in the mandible without FOS gene rearrangement. According to a review of previously reported cases of osteoblastoma, FOS gene rearrangement is significantly less common in patients > 40 years of age (P = 0.041). Osteoblastomas occurring in older adult patients may exhibit pathogeneses different from those of young patients. Further data, including the relationship between age and FOS gene rearrangement, is necessary to clarify the pathogenesis of osteoblastoma. [ABSTRACT FROM AUTHOR]

Massive osteolysis is an extremely rare condition characterized by progressive osteolysis. In this report, we present a case of massive osteolysis in the upper and lower jaws. A 49-year-old man was referred to our hospital because of bone resorption in the jaw of an unknown cause. Panoramic radiography and computed tomography (CT) showed extensive bone resorption in the right lower and left upper jaws. The biopsy specimen revealed marked non-specific inflammatory granulation tissue without any malignant findings. Although this case lacked significant lymphatic growth in the biopsy specimen, the clinical diagnosis of massive osteolysis was made, and two courses of zoledronic acid, which has been recently reported to be effective in the disease, were administered. CT performed 19 months after the initial examination showed no new osteolysis, and the patient was free of symptoms. [ABSTRACT FROM AUTHOR]

Mandibular brown tumors are often radiographically and histologically indistinguishable from cherubism, aneurysmal bone cyst, giant cell granuloma, and odontogenic fibroma. Laboratory findings of hyperparathyroidism (HPT) aid in directing therapy. We present a case of a 14-year-old male with a brown tumor of the mandible associated with secondary HPT due to vitamin D deficiency. Core biopsy exhibited a proliferation of plump spindle cells and osteoclast-like giant cells within variably fibrous stroma. Parathyroid hormone (PTH) levels were elevated to 288 pg/mL (normal 8.5-77.1 pg/mL) and vitamin D was low at a level of 6.9 ng/mL (normal > 20.0 ng/mL). Six months after the introduction of weekly vitamin D supplementation, PTH and vitamin D levels improved but remained abnormal with PTH of 86.8 pg/mL and vitamin D of 9.3 ng/mL. Alongside an improvement in laboratory indices, the tumor character stabilized and became less clinically friable; however, the burden remained unchanged. At 9 months, the patient underwent surgical debulking of the tumor with local soft tissue coverage. A review of pediatric literature was performed, among which 16 patients were identified. Most children who developed brown tumors were found to have secondary HPT and ultimately 44% underwent some degree of surgical debridement of the mass. [ABSTRACT FROM AUTHOR]

Background: The mandible of the rabbit is considered a reliable model to be used to study bone regeneration in defects. The aim of the present study was to evaluate the formation of new bone around implants installed in defects of either 5 or 10 mm in the mandible of rabbits. Materials and methods: In 12 rabbits, 3 mm deep circumferential defect, either 5 or 10 mm in diameter, were prepared bilaterally and an implant was placed in the center. A collagen membrane was placed to close the entrance. After 10 weeks, biopsies were taken, histological slides were prepared, and different regions of the defects were analyzed. Results: Similar amounts of new bone were found in both defects. However, most of the 5 mm defects were filled with new bone. New bone was observed closing the entrance of the defect and laid onto the implant surface. Only in a few cases the healing was incomplete. Despite a similar percentage of new bone found within the 10 mm defects, the healing was incomplete in most of the cases, presenting a low rate of bone formation onto the implant surface within the defect. Only one case presented the closure of the entrance. Conclusions: The dimensions of the defect strongly influenced the healing so that a circumferential marginal defect of 10 mm around an implant in the mandible body should be considered a critical-sized defect. The presence of the implant and of residues of teeth might have strongly influenced the healing. [ABSTRACT FROM AUTHOR]

Background: To avoid cortical compression, several implant systems have included in the protocol dedicated drills aimed at widening the cortical region of osteotomy. However, the manual execution of this operation does not guarantee the necessary precision. Hence, the present study aimed to determine the optimal size of the recipient site at the level of the alveolar crest in relation to the size of the coronal region of the implant to achieve the best healing result. Materials and methods: Blades of different diameters were incorporated into the coronal part of the implant to prepare the cortical region of the mandibular alveolar bone crest in different dimensions in relation to the collar of the implant. The differences in diameter of the blades in relation to the collar of the implant were as follows: one control group, -175 μm, and three test groups, 0 μm, + 50 μm, or + 200 μm. Results: The marginal bone loss (MBL) at the buccal aspect was 0.7 mm, 0.5 mm, 0.2 mm, and 0.7 mm in the − 175 μm, 0.0 μm, + 50 μm, + 200 μm groups, respectively. The differences were statistically significant between group + 50 μm and control group − 175 μm (p = 0.019), and between + 50 μm and + 200 μm (p < 0.01) groups. The level of osseointegration at the buccal aspect was more coronally located in the test groups than in the control group, whereas the bone-to-implant contact percentage was higher in the + 50 μm and + 200 μm groups. However, these differences were not statistically significant. Conclusions: The lowest bone crest resorption and highest levels of osseointegration were observed in the 0.0 μm and + 50 μm groups. The cortical region where the blades had performed their cutting action showed regular healing with perfect hard and soft tissues sealing in all the groups. Cortical blades gathered bone particles, particularly in the + 200 μm group, which were incorporated into the newly formed bone. The results from the present experiment provide support to the use of blades that produce a marginal gap of 50 μm after implant insertion. [ABSTRACT FROM AUTHOR]

Objective: This study evaluated the effectiveness of a submental island flap in closing advanced mandibular medication‐related osteonecrosis of the jaw (MRONJ) wounds in patients with malignant tumors. Subjects and methods: A total of 85 patients with stage II and III MRONJ of mandible with malignant tumor as their primary disease were retrospectively analyzed. All patients underwent surgical treatment, and the soft tissue wound closure was performed either with a submental island flap (SIF) or mucoperiosteal flap (MF). Univariate and multifactorial models were applied to analyze the factors influencing patients' prognosis. Results: Univariate analysis (p = 0.004, OR 0.075–0.575, 95% CI) and binary logistic regression (p = 0.017, OR 0.032–0.713, 95% CI) suggested that the surgical prognosis of SIF wound closure was significantly better than that of MF. Conclusion: Closure of wound after resection of mandibular MRONJ lesions in patients with malignant tumors using SIF had a better clinical prognosis compared with MF. [ABSTRACT FROM AUTHOR]

Background Objective Methods Results Conclusion Masticatory muscle training by chewing gum can be performed easily and improve masticatory muscle function and strength. However, increased masticatory muscle activity and function may alter the mandibular shape.We aimed to investigate the effects of gum chewing training on the occlusal force, masseter muscle thickness (MMT) and mandibular shape in healthy adults.We conducted a prospective randomised controlled trial from January 2020 to September 2020 at the Yonsei University College of Dentistry. Fifty‐eight participants were randomly assigned to the training and control groups. The training group chewed gum three times a day for 6 months, while the control group received no training. Changes in the maximum occlusal force and MMT were evaluated at baseline and after 1, 3 and 6 months. Changes in the mandibular shape were evaluated at baseline and after 6 months.The mean maximum occlusal force of the training group at 3 months was significantly higher than that at baseline, which was also significantly different from that in the control group (p < .001). As the maximum occlusal force increased, the occlusal contact area also increased (p = .020). There was no statistically significant difference in MMT or mandibular shape compared to the baseline.Mastication training using gum increases maximum occlusal force due to an increase in occlusal contact area but has no effect on MMT or mandibular shape. [ABSTRACT FROM AUTHOR]

ABSTRACT Background Objective Methods Results Conclusion Nasal obstruction in humans leads to mouth breathing and subsequent hypoxia in the entire body. Furthermore, nasal obstruction in growing children affects craniofacial growth and development.To investigate the effects of unilateral nasal obstruction (UNO) on craniofacial growth in mice of different ages, particularly on the morphology of the nasomaxillary complex and mandible.Mice aged 3, 6 and 12 weeks were selected as representatives of juvenile, adolescent and adult stages, respectively. A total of 30 male C57BL/6J mice (10 mice each at the ages of 3, 6 and 12 weeks) were used in this study for a 3‐week experiment. The mice in each age stage were randomly and evenly assigned to either the control group (C3+3, C6+3 and C12+3) or the experimental group (E3+3, E6+3 and E12+3). The UNO model in experimental group was constructed by plugging the mouse's left nostril, thereby disrupting its normal nasal breathing pattern and inducing hypoxia. The control group underwent the sham procedure. After 3 weeks, the length, width and height of the cranium, nasomaxillary complex and mandible of each group were measured on two‐dimensional images constructed by micro‐computed tomography. Furthermore, the impact of UNO on mouse growth was evaluated through the measurement of femoral length.In juvenile mice, UNO inhibited the growth of cranial width, cranial height and mandibular length. In adolescent mice, UNO impeded the growth of the femoral length, cranial length, nasomaxillary length and mandibular length. In adult mice, no significant negative effects of UNO on craniofacial growth were found.Referring to the experimental results, in addition to actively treating nasal obstruction in patients, it is important to monitor the growth of the mandible in juveniles, as well as the nasomaxillary and mandibular growth in adolescents during orthodontic clinical practice. [ABSTRACT FROM AUTHOR]

Background: The aim of this study was to investigate the etiologies of non-surgical root canal treatment (NS-RCT) in a Thai population and examine their association with risk factors. Methods: A cross-sectional observational study was performed to examine the etiologies of NS-RCT and risk factors among Thai-nationality patients treated at a tertiary care dental hospital in Thailand from 2019–2023. Treatment records and radiographs were retrospectively reviewed to identify NS-RCT etiologies, and associated contributing factors were analyzed. Statistical analysis used univariate logistic regression followed by multivariate logistic regression, with a significance level set at P < 0.05. Results: The data from 1500 teeth were analyzed, comprising 59.1% females and 40.9% males, with ages ranging from 7–91 years (mean = 48.56 years). The most prevalent age group was 61–70 years-old. Among the treated teeth, the mandibular first molar was the most frequently involved (13.9%), followed by the maxillary first molar (9.9%) and mandibular second premolar (9.7%). The primary etiologies of NS-RCT were dental caries (53.7%), old and large restorations (7.9%), and attrition (5.9%). Analysis of etiology of NS-RCT due to caries revealed that the most commonly affected sites were the occlusal (32.6%), distal (31.6%), and mesial (17.2%) surfaces. In immature teeth requiring NS-RCT, the predominant etiologies were dens evaginatus (32.1%), dental caries (28.6%), and traumatic injury (21.4%). The association between the etiology of NS-RCT and investigated associated factors were identified. Conclusions: The etiologies of NS-RCT in the selected Thai population were mainly attributed to dental caries, with additional factors being old and large restorations and attrition. Notably, due to the aging society, the elderly population experiences a higher demand for NS-RCT, particularly due to attrition, non-carious cervical lesions, and erosion. In contrast, in immature teeth, the most common etiologies leading to NS-RCT comprise dens evaginatus, dental caries, and traumatic injuries. The distinct etiological patterns observed in different age groups emphasize the importance of specific oral health prevention programs to address individual needs. [ABSTRACT FROM AUTHOR]

Background: Patients presenting with partially impacted lower third molars (M3) have a higher likelihood of experiencing angle fractures while simultaneously decreasing the risk of condylar fractures. However, the specific biomechanical mechanism responsible for this occurrence remains unclear. Moreover, there is an ongoing debate regarding whether the removal of M3s might actually increase the risk of condylar fractures. This study aimed to evaluate how the presence of M3s influences mandibular fractures resulting from blows to the symphysis and lateral mandibular body, and to determine the indication for extracting M3s in such cases. Methods: Models of the mandible with a partially M3-impacted model (M3I), M3-extracted model (M3E), and M3-absent model (M3A) were generated using a computer. A traumatic blown force of 2000 N was applied to the symphysis and the right body of the mandible. Von Mises and principal stresses were analyzed, and failure indexes were determined. Two cases of mandibular linear fractures were chosen for model verification and interpretation. Results: When force was applied to the symphysis, the condylar region exhibited the highest stress levels, while stress in the mandibular angle region was much less regardless of the M3 state. On applying the force to the right mandibular body, stress in the condylar region decreased while stress in the mandibular body increased, especially in the blown regions. Impacted tooth or cavity formation post-M3 extraction led to uneven stress distribution on the blown side of the mandible, increasing the risk of mandibular angle fractures. In cases where M3 was absent or the extraction socket had healed, stress from lateral traumatic blown force was evenly distributed along both the inner and outer oblique lines of the mandible, thereby reducing the risk of mandibular fractures. Conclusions: The reduced risk of condylar fractures in patients with partially impacted lower M3s and mandibular angle fractures is mainly due to lateral blows on the mandible, which generate less stress in the condylar region than blows on the mandibular symphysis, rather than being caused by the M3 itself. Extraction of the lower M3 can decrease the risk of mandibular fractures, with a minor influence on condylar fractures. [ABSTRACT FROM AUTHOR]

Neoplastic processes of the mandible and their treatment are rarely reported in large animal species. Specifically, giant cell tumor of bone is an uncommon tumor in animals and has been associated in humans with locally invasive behavior and a high recurrence rate. En-bloc resection is the treatment of choice, but depending on the localization of the tumor, this may result in functional deficits. This report details the diagnostic work-up, treatment, and long-term outcome of a giant cell tumor of bone involving the rostral mandible and mandibular symphysis of a goat. Extensive rostral mandibulectomy involving the entire mandibular symphysis without surgical fixation of the hemimandibles was performed. Histological and electron microscopic findings of the tumor were consistent with a giant cell tumor of bone. Although a mutation of the H3F3A gene is considered the driver of tumor development in human giant cell tumors, using molecular analysis, this gene mutation could not be confirmed in this case. Follow-up examinations revealed spontaneous secondary fusion of both hemimandibles and no signs of tumor recurrence. Nearly 1 year after surgery, the owners reported no signs of tumor regrowth. [ABSTRACT FROM AUTHOR]

BACKGROUND: Some studies have found that local application of alendronate can promote osteogenesis, but less is reported on the process of distraction osteogenesis. OBJECTIVE: To observe the promoting effect of alendronate on rapid mandibular distraction in a rabbit model and explore its possible mechanism. METHODS: Thirty-six male New Zealand white rabbits were randomly divided into groups A, B and C (n=12 per group) after operation and rapid distraction (3- day delay period followed by 3-day distraction at 1.5 mm/12 hours). At the 1st, 3rd and 7th days of the consolidation period, animal were injected with 200 μg/kg alendronate in group A and 100 μg/kg alendronate in group B, while those in group C were treated as controls. CT scanning and dual energy X-ray bone mineral density measurement were performed at 4 and 8 weeks of the consolidation period. After the radionuclide scanning was completed at the 4th week, several animals were sacrificed and the samples were collected for western blot assay and tartrate resistant acid phosphatase staining. A three-point bending test was performed after the animals were sacrificed at the 8th week. RESULTS AND CONCLUSION: CT results showed that bone formation in the distraction space of group B was significantly better than that in groups A and C. At the 4th week, the bone mineral density in group B was (0.092±0.010) g/cm², which was 1.26 times higher than that in group A (P < 0.001) and 1.28 times higher than that in group C (P < 0.001). At the 8th week, the bone mineral density in group B was (0.175±0.029) g/cm², which was 1.38 times higher than that in group A (P < 0.001) and 1.45 times higher than that in group C (P < 0.001). Tartrate resistant acid phosphatase staining showed that the number of osteoclast-like cells in group C were 2.83 times more than that in group A (P < 0.001) and 2.21 times more than that in group B (P < 0.001). The radionuclide intensity was higher in group C than in groups A and B. Western blot assay results showed that the expression of Runx2 was significantly stronger in group B than in groups A and C. The maximum biomechanical load in group B was (158.48 ± 23.21) N, which was 1.26 times higher than that in group A (P=0.007) and 1.31 times higher than that in group C (P=0.003). To conclude, the low concentration of alendronate may promote rapid distraction osteogenesis of the rabbit mandible by inhibiting osteoclast signals. [ABSTRACT FROM AUTHOR]

Background: This study investigated the characteristics of Monson's sphere in Chinese young adult females with individual normal occlusion to provide a reference for oral rehabilitation in prosthodontic and orthodontic treatments. Methods: Points at the dental cusps and incisal edges were selected from 51 digital mandibular dental models of Chinese young adult females (aged 18–22 years) with individual normal occlusion. Monson's spheres were fitted to the selected points based on the least-squares principle and the radii were calculated. The deviation of each selected point from its relative spherical surface was also calculated. The radii and deviations of these points were examined using conventional descriptive statistics and distributions of the most deviated points inside and outside the spheres were analyzed. Results: The mean radius of Monson's sphere in Chinese young adult females was 79.60 ± 14.13 mm. The deviation of each selected point from its relative sphere surface was 0.38 ± 0.30 mm. The maximum deviations inside and outside the sphere were 0.93 ± 0.25 mm and 0.95 ± 0.30 mm, respectively. The most deviated points outside the spheres were mainly distributed at the distolingual cusps of the mandibular second permanent molars (31.37%), while those inside the spheres were mainly distributed at the mesiolingual cusps of the mandibular first permanent molars (45.10%). Conclusions: The radius of Monson's sphere in Chinese young adult females was smaller than the classic four-inch value suggested by Monson. Deviation was observed from all selected points to their Monson's sphere surface, with the most deviated points distributed primarily in the molar region. [ABSTRACT FROM AUTHOR]

Background: Tumorous diseases of the jaw demand effective treatments, often involving continuity resection of the jaw. Reconstruction via microvascular bone flaps, like deep circumflex iliac artery flaps (DCIA), is standard. Computer aided planning (CAD) enhances accuracy in reconstruction using patient-specific CT images to create three-dimensional (3D) models. Data on the accuracy of CAD-planned DCIA flaps is scarce. Moreover, the data on accuracy should be combined with data on the exact positioning of the implants for well-fitting dental prosthetics. This study focuses on CAD-planned DCIA flaps accuracy and proper positioning for prosthetic rehabilitation. Methods: Patients post-mandible resection with CAD-planned DCIA flap reconstruction were evaluated. Postoperative radiograph-derived 3D models were aligned with 3D models from the CAD plans for osteotomy position, angle, and flap volume comparison. To evaluate the DCIA flap's suitability for prosthetic dental rehabilitation, a plane was created in the support zone and crestal in the middle of the DCIA flap. The lower jaw was rotated to close the mouth and the distance between the two planes was measured. Results: 20 patients (12 males, 8 females) were included. Mean defect size was 73.28 ± 4.87 mm; 11 L defects, 9 LC defects. Planned vs. actual DCIA transplant volume difference was 3.814 ± 3.856 cm³ (p = 0.2223). The deviation from the planned angle was significantly larger at the dorsal osteotomy than at the ventral (p = 0.035). Linear differences between the planned DCIA transplant and the actual DCIA transplant were 1.294 ± 1.197 mm for the ventral osteotomy and 2.680 ± 3.449 mm for the dorsal (p = 0.1078). The difference between the dental axis and the middle of the DCIA transplant ranged from 0.2 mm to 14.8 mm. The mean lateral difference was 2.695 ± 3.667 mm in the region of the first premolar. Conclusion: The CAD-planned DCIA flap is a solution for reconstructing the mandible. CAD planning results in an accurate reconstruction enabling dental implant placement and dental prosthetics. [ABSTRACT FROM AUTHOR]

Background: Orofacial clefts are one of the most common congenital malformations of the fetal face and ultrasound is mainly responsible for its diagnosis. It is difficult to view the fetal palate, so there is currently no unified standard for fetal palate screening, and the diagnosis of cleft palate is not included in the relevant prenatal ultrasound screening guidelines. Many prenatal diagnoses for cleft palate are missed due to the lack of effective screening methods. Therefore, it is imperative to increase the display rate of the fetal palate, which would improve the detection rate and diagnostic accuracy for cleft palate. We aim to introduce a fetal palate screening software based on the "sequential sector scan though the oral fissure", an effective method for fetal palate screening which was verified by our follow up results and three-dimensional ultrasound and to evaluate its feasibility and clinical practicability. Methods: A software was designed and programmed based on "sequential sector scan through the oral fissure" and three-dimensional ultrasound. The three-dimensional ultrasound volume data of the fetal face were imported into the software. Then, the median sagittal plane was taken as the reference interface, the anterior upper margin of the mandibular alveolar bone was selected as the fulcrum, the interval angles, and the number of layers of the sector scan were set, after which the automatic scan was performed. Thus, the sector scan sequential planes of the mandibular alveolar bone, pharynx, soft palate, hard palate, and maxillary alveolar bone were obtained in sequence to display and evaluate the palate. In addition, the feasibility and accuracy of the software in fetal palate displaying and screening was evaluated by actual clinical cases. Results: Full views of the normal fetal palates and the defective parts of the cleft palates were displayed, and relatively clear sequential tomographic images and continuous dynamic videos were formed after the three-dimensional volume data of 10 normal fetal palates and 10 cleft palates were imported into the software. Conclusions: The software can display fetal palates more directly which might allow for a new method of fetal palate screening and cleft palate diagnosis. [ABSTRACT FROM AUTHOR]

Considerable morphological and ecological diversity has been found in extinct and extant members of the bear genus, Ursus, and appears to be key in explaining how they have thrived across vast ecological gradients. One example is the cave bear Ursus spelaeus. We applied 2D geometric morphometric techniques to describe morphological changes in the mandibles of extant Ursus species to further interpret the palaeoecology of U. spelaeus. Ursus species were discriminated using their mandibular morphology, which showed intra and interspecific shape variation that was indirectly linked to climatic adaptations through dietary variation. Mandibles of bears that inhabit colder, drier and more seasonal environments were generally slender with large diastema and a dorsoventrally smaller ramus. In contrast, species from warmer environments with higher levels of precipitation were found to have a dorsoventrally taller ramus (relative to the corpus). Discriminant function analyses of the morphology of U. spelaeus suggested adaptations to a series of fluctuating environments through time, helping to assess previously proposed Marine Isotope Stages for sedimentary deposits in Scladina Cave. Our geometric morphometrics analyses of bear mandibular ecomorphology demonstrates how geometric morphometrics provides a valuable tool to enhance paleoenvironmental reconstructions within deposits of the same fossil site. [ABSTRACT FROM AUTHOR]

Background: There is insufficient evidence recommending a framework material and a CAD/CAM manufacturing technique for mandibular implant-supported prostheses. The study objective was to evaluate the clinical application of different materials and construction techniques used for mandibular All-on-4 prosthesis on circumferential peri-implant bony changes after 5 years. Methods: Thirty-six male patients with all-on-4 mandibular implant-supported prostheses were recalled and divided into three groups. Group PK (patients with frameworks milled from PEEK blocks), Group PSM (patients with frameworks milled from soft metal blocks), and Group SLM (patients with frameworks constructed with additive manufacturing; selective laser melting). The circumferential bone level on all implant faces was assessed with a CBCT. Two-way repeated measures ANOVA was used to compare vertical bone loss (VBL) and horizontal bone loss (HBL) between different groups, implant positions, and observation times followed by Tukey's multiple comparisons. Results: For all observation times, there was a significant difference in VBL between groups for both anterior and posterior implants (P <.001). For anterior implants, group PSM showed the lowest VBL while group PK showed the highest for anterior and posterior implants. For all groups, HBL significantly increased after 5 years for both anterior and posterior implants (P <.001). For anterior implants, group PSM showed the highest HBL. For posterior implants, group PK and SLM showed the highest. Conclusion: Within the study's limitations, mandibular implant-supported fixed frameworks fabricated with either milling from PEEK or soft metal blocks, or additive manufacturing (laser melting technology) exhibited significant vertical and horizontal bone height changes after 5 years. Clinical Trial Registry Number: (NCT06071689) (11/10/2023). [ABSTRACT FROM AUTHOR]

Purpose: To retrospectively evaluate peri-implant bone loss and health status associated with the long-term use of laser surface-treated implants. Methods: For control study, total of 23 titanium ASTM F136 grade 23 implants were placed in the edentulous molar area of the mandible. When the Implant Stability Quotient (ISQ) ≥ 70 and insertion torque value (ITV) ≥ 35–50 Ncm at the insertion site, an immediate provisional restoration was connected to the implant within a week after surgery. The definitive restorations were placed 2 months after surgery for all implants. 13 implants were immediately loaded, while 10 implants were conventionally loaded. For comparative study, Radiographs were taken from third years for and then annually for the subsequent eight years to monitor marginal bone loss. Results: After eight year of implant installation, the average change in vertical bone loss was 0.009 mm (P < 0.001), while the average change in horizontal bone loss 8 year after implant placement was 0.026 mm (P < 0.001). The mean marginal bone loss was < 0.2 mm on average. Conclusions: In this retrospective study, laser-treated implants exhibit a low rate of bone absorption around the implants. [ABSTRACT FROM AUTHOR]

Background/Aim. Given that frequent manipulation of the abutment during immediate loading can have a negative impact on the surrounding peri-implant hard and soft tissues, the concept "one abutment at one time" (OAO) has been introduced and documented in daily clinical practice. The a im of the study was to evaluate c hanges i n p eriimplant bone levels, clinical and radiographic parameters, and patient perspectives during the six-month follow-up period. Methods. The study was designed as a randomized controlled clinical trial. Patients with bilaterally healed sites in the posterior mandible received implants with a diameter of no less than 3.5 mm and a length of at least 8 mm. Based on randomization, patients were divided into a test group and a control group. Patients who were in the test group received implants that were immediately loaded with definitive abutments. In contrast, patients in the control group received implants where healing abutments were placed, followed by temporary abutments. Implants were immediately loaded with provisional restorations within the first seven days. They were delivered over the test group's definitive abutment and the control group's temporary abutment. Probing depth, bleeding on probing, clinical attachment level, plaque index, and keratinized tissue width were measured. Patient-Reported Outcome Measures and the Oral Health Impact Profile - 19 (OHIP-19) questionnaires were noted. Results. Out of 24 included patients, 22 completed the six-month follow-up. Peri-implant bone loss between study groups was comparable (mesial: t = -0.798, df = 21, p = 0.434; distal: t = 1.688, df = 21, p = 0.106), without statistical inter-group significance. OHIP-19 total scores significantly decreased after three months and remained similar six months after the implant placement in both groups without statistically relevant clinical inter-group changes. Conclusion. The OAO approach and provisional abutments showed comparable effectiveness regarding the immediate loading of posterior single implants. [ABSTRACT FROM AUTHOR]