The influence of bone block graft position on bone dimensional changes in staged onlay horizontal ridge augmentation: A 6-month retrospective cohort study.

OBJECTIVES: To analyze changes in bone dimensions and their modulating factor in bone dimensions 6 months after horizontal ridge augmentation using autogenous bone grafts. MATERIALS AND METHODS: Thirty-eight patients with horizontally atrophic alveolar ridges of a single edentulous tooth at the maxillary anterior site were divided into two groups based on the fixation position of the bone block during ridge augmentation surgery (H0, vertical distance from the upper edge of the bone block to the alveolar crest). Patients were classified into a crestal level (CL) group if H0 ≤ 1 mm and a sub-crestal level (SCL) group if H0 > 1 mm. The width and height of the alveolar ridge were recorded using CBCT both before and 6 months after the augmentation procedure. RESULTS: The CL group comprised 20 patients with 23 implants, whereas the SCL group comprised 18 patients with 22 implants. All the augmentation sites exhibited vertical bone resorption. Vertical bone resorption in the SCL group (1.94 ± 2.11 mm) was significantly higher than that of the CL group (0.61 ± 0.64 mm). The SCL group showed significantly lower horizontal bone gain than the CL group (SCL: 1.02 ± 2.30 mm; CL: 3.19 ± 3.17 mm) at the cervical level. Peri-implant marginal bone loss increased significantly in the SCL group (1.00 ± 2.71 mm) compared to the CL group (0.64 ± 0.40 mm). CONCLUSION: The bone height decreased after horizontal ridge augmentation using autogenous onlay grafting. The fixation position of the bone block was a modulating factor. The SCL group showed more vertical bone loss, less horizontal bone gain 6 months after surgery, and more marginal bone loss after restoration.

Clinical success of guided tissue regeneration for treating vertical bone and furcation defects in dogs.

This study evaluated the clinical success rate of guided tissue regeneration (GTR) for treating advanced periodontal disease in a large canine cohort. A total of 112 GTR procedures performed from 2003-2021 were retrospectively evaluated, including pre- and post-treatment (3-12 months) periodontal probing depths of 104 treated teeth, dental radiographs of 73 treated teeth, and both diagnostic modalities in 64 treated teeth. Probing depth, radiographically apparent bone height, bone graft material, barrier membrane material, and tooth extraction adjacent to the GTR site were investigated as factors affecting success. Vertical bone defects were evaluated separately from furcation defects. GTR was clinically successful, defined as objective improvement in probing depth, objective decrease in radiographic vertical bone defect, and subjective radiographic gain in bone height in 90.3% of vertical bone defects. Success was significantly associated with the magnitude of initial probing depth and the type of barrier membrane used. GTR was clinically successful, defined as objective improvement in furcation probing and subjective radiographic improvement of the bone in the furcation in 22.2% of furcation defects. When F3 lesions were excluded, GTR was successful in 64.3% of furcation defects. GTR is an appropriate treatment to maintain teeth in the oral cavity of dogs with proper client counseling and patient selection, but it is most likely to be successful in vertical defects.

Comparative Study by Systematic Review and Meta-Analysis of the Peri-Implant Effect of Two Types of Platforms: Platform-Switching versus Conventional Platforms.

OBJECTIVE: The aim of the systematic review and meta-analysis carried out was to evaluate the effects of changing the prosthetic platform on peri-implant tissue after 1 year of prosthetic loading. MATERIAL AND METHODS: In November 2020, an electronic search was carried out in PubMed, EMBASE, Web of Science, and Scopus databases with the aim of obtaining all the randomized clinical trials that had been published in the preceding 10 years comparing the effects on the peri-implant tissue of implants with a prosthetic platform change and implants with a conventional platform for at least 1 year after prosthetic loading. Randomized model meta-analyses of the selected studies were performed to compare the results of the two implant groups in terms of vertical maintenance of bone level and increased probing depth. RESULTS: Nine studies were included, summing up a total of 475 implants with prosthetic platform exchange and 462 implants with a conventional platform. Implants with prosthetic platform exchange had less peri-implant bone loss than implants with a conventional platform (mean difference of 0.255 mm, statistically significant) but suffered a greater increase in probing depth (mean difference of 0.082 mm, not statistically significant). However, the probing depth from One Study Remove revealed a statistically significant increase of 0.190 mm in the prosthetic platform exchange group compared to the conventional platform group. CONCLUSION: Implants with platform switching suffer less peri-implant bone loss after 1 year of loading than implants with a conventional platform. Further long-term studies are required to observe how these differences vary over time.

Types of bone destruction and its severity in chronic periodontitis patients with tobacco smoking habit using periapical radiographs and transgingival probing: A cross-sectional study.

BACKGROUND: Tobacco smoking is an independent risk factor for periodontal disease which increases periodontal pocketing, attachment loss, as well as bone loss leading to varied severity and bone destruction in the form of horizontal and vertical patterns. AIM: The aim of the present study is to determine and measure the types and severity of bone destruction in chronic periodontitis (CP) patients with tobacco smoking habit using intraoral periapical (IOPA) radiographs and transgingival probing. MATERIALS AND METHODS: A total of 60 male participants with CP were included in the study. Group A comprised 30 heavy cigarette smokers and Group B comprised 30 nonsmokers. Clinical parameters such as plaque index (PI), probing pocket depth (PPD), and clinical attachment loss (CAL) were recorded. Amount and pattern of bone loss were assessed using IOPA and transgingival probing. RESULTS: The mean values of PI, PPD, and CAL were 2.50 ± 0.28 mm, 9.33 ± 1.42 mm, and 10.2 ± 1.62 mm, respectively, for cigarette smokers, which were found to be higher and statistically significant as compared to nonsmokers. Cigarette smokers showed more bone destruction than nonsmokers in respect to maxillary molars 4.42 ± 1.31 mm and incisors 3.90 ± 1.10 mm as compared to nonsmokers. Types of bone destruction were more of vertical patterns (93.3%) in cigarette smokers. CONCLUSIONS: Tobacco smoking was associated with severe attachment loss. Tobacco smoking not only affects soft tissues but also hard tissues such as bone. Palatal sides of maxillary molars showed significantly higher bone loss and also had more percentage of vertical patterns of bone loss compared to nonsmokers. IOPA and transgingival probing may be used as noninvasive methods for the determination of types and severity of bone destruction in CP patients with or without tobacco smoking habit.

In Vivo Detection of Subtle Vertical Root Fracture in Endodontically Treated Teeth by Cone-beam Computed Tomography.

INTRODUCTION: The purpose of this study was to evaluate the diagnostic accuracy of cone-beam computed tomographic (CBCT) imaging in the detection of subtle vertical root fractures (VRFs) in endodontically treated teeth in vivo and to discuss direct and indirect evidence for the diagnosis of subtle VRFs. METHODS: Twenty-nine endodontically treated teeth with suspected VRFs from 29 patients were examined using CBCT imaging. CBCT images were scored based on evaluation of the fracture line and vertical buccopalatal (lingual) bone loss. VRF was diagnosed only when a definite fracture line was detected on CBCT images, and findings of periodontal exploration or surgical extraction were considered the gold standard. The diagnostic sensitivity, specificity, and accuracy were assessed. RESULTS: Of the 29 teeth, 27 were positive and 2 were negative for VRF according to the gold standard. Sensitivity, specificity, and accuracy were 33.3%, 100%, and 37.9%, respectively, based on the direct finding of a fracture line on CBCT images. However, vertical buccopalatal (lingual) bone loss was found in 25 of 27 teeth with VRFs. CONCLUSIONS: Although the accuracy of CBCT imaging for the diagnosis of subtle VRFs in endodontically treated teeth in vivo was poor, vertical buccopalatal (lingual) bone loss is an important indirect sign for the diagnosis of VRFs, which can be found on CBCT images.

An analysis of the vertical bone loss in edentulous mandibles by using the mental foramen as a reference: a radiographic study.

OBJECTIVES: To analyze the amount of vertical bone loss in edentulous mandibles by using the mental foramen as a reference. METHOD: Ninety subjects who consisted of thirty dentulous (males I MD and females II FD) and sixty edentulous (males I ME and females II FE) subjects were selected and they were subjected to digital panoramic radiography. Among the dentulous subjects, in both the groups, the ratio between the height of the mandible and the distance from the mental foramen and the lower border of the mandible (A/B) were calculated by using inbuilt software. This ratio A/B was applied in the edentulous subjects to measure the original height of the mandible before resorption. The amount of vertical bone loss was then calculated. RESULTS: In the dentulous subjects, the A/B ratio in males was 2.94 and in females, it was 3.09. In the edentulous subjects, the vertical bone loss in males was 3.55mm and in females, it was 6.59mm. CONCLUSION: The ratio of the distance from the inferior border of the mandible to the superior border of the mandible(A) and the distance from the inferior border of the mandible to the inferior margin of the mental foramen (B) were less in the dentulous males than in the dentulous females. The comparison of the ratios was nonsignificant. The mean bone loss in edentulous females was found to be greater than the mean bone loss in edentulous males on comparison.

Influence of bone loss pattern on stress distribution in bone and implant: 3D-FEA study / 대한치과보철학회지

PURPOSE: This 3D-FEA study was performed to investigate the influence of marginal bone loss pattern around the implant to the stress distribution. MATERIAL AND METHODS: From the right second premolar to the right second molar of the mandible was modeled according to the CT data of a dentate patient. Teeth were removed and an implant (small ef, Cyrillic 4.0 x 10.0 mm) was placed in the first molar area. Twelve bone models were created: Studied bone loss conditions were horizontal bone loss and vertical bone loss, assumed bone loss patterns during biologic width formation, and pathologic vertical bone loss with or without cortification. Axial, buccolingual, and oblique force was applied independently to the center of the implant crown. The Maximum von Mises stress value and stress contour was observed and von Mises stresses at the measuring points were recorded. RESULTS: The stress distribution patterns were similar in the non-resorption and horizontal resorption models, but differed from those in the vertical resorption models. Models assuming biologic width formation showed altered stress distribution, and weak bone to implant at the implant neck area seams accelerates stress generation. In case of vertical bone resorption, contact of cortical bone to the implant may positively affect the stress distribution.

Unilateral gingival fibromatosis with localized aggressive periodontitis (involving first molars): An unusual case report.

An atypical and rare case report is presented here of a 16 years old female patient who presented with severe, unilateral, gingival enlargement along with aggressive periodontitis around first molars that was confined to the left side of her mouth. A careful recording of the case history and results of clinical examination, laboratory blood analysis, radiological findings, and microbiological and histopathological investigations were noted and a critical review of similar conditions was taken into account to arrive at the said diagnosis.