Investigating the effects of buccal bone fenestration on maxillary anterior implants: A 1- to 6-year retrospective study.

PURPOSE: To examine the effects of buccal bone fenestration on maxillary anterior implants. MATERIALS AND METHODS: Patients who underwent implant placement in the maxillary anterior region between January 2017 and December 2021 and had received final restorations 1 to 6 years prior were screened for inclusion in the present study. Propensity score matching was used to match the two-group sample size and reduce the influence of potential confounding factors. Generalised linear mixed models were employed to evaluate the correlation between buccal bone fenestration and peri-implant marginal bone loss. RESULTS: A total of 42 patients with 50 implants were included in the study, 16 of whom had buccal bone fenestration (group 1) and 26 of whom did not (group 2). No implant failures occurred, resulting in a cumulative implant survival rate of 100.0%. There was no statistically significant difference between the pink aesthetic scores for the two groups. The mean marginal bone loss was 0.44 ± 0.46 mm for group 1 and 0.33 ± 0.32 mm for group 2 (P > 0.05). Buccal bone fenestration was not the influencing factor of marginal bone loss (P > 0.05). Marginal bone loss was greater around implants used to replace canines than those inserted to replace central incisors (P < 0.05). Far less marginal bone loss occurred around immediately loaded implants than delayed implants with cover screws (P < 0.05). When there is sufficient keratinised mucosa around the implant, marginal bone loss will decrease significantly (P < 0.05). CONCLUSIONS: Within the limitations of this study, buccal bone fenestration defects around dental implants cannot influence peri-implant bone loss. CONFLICT-OF-INTEREST STATEMENT: The authors report no conflicts of interest relating to this study.

Implant Placement with Simultaneous Guided Bone Regeneration in the Anterior Region Close to the Periapical Lesion of Adjacent Teeth: A Combined Treatment Strategy to Prevent Complications.

PURPOSE: To evaluate the safety and performance of a potential novel strategy to resolve the above scenario by simultaneously performing implant-related surgery and endodontic microsurgery (EMS). MATERIALS AND METHODS: A total of 25 subjects requiring GBR during implant placement in anterior areas were allocated into two groups. In the experimental group (adjacent teeth with periapical lesions) with 10 subjects, implantation and GBR were performed for edentulous areas with simultaneous EMS for adjacent teeth. In the control group (adjacent teeth without periapical lesions) with 15 subjects, implantation and GBR were performed for edentulous areas. The clinical outcomes, radiographic bone remodeling, and patient-reported outcomes were assessed. RESULTS: Within a 1-year follow-up, the implant survival rate was 100% in both groups, with no significant difference regarding complications. All teeth achieved complete healing following EMS. Repeated analysis of variance (ANOVA) measurements revealed a significant change over time in horizontal bone widths and postoperative patient-reported outcomes, but no intergroup statistically significant differences (P > .05) in horizontal bone widths and visual analog scale scores of pain, swelling, and bleeding were observed. Likewise, the bone volumetric decrease (7.4% ± 4.5% in the experimental group and 7.1% ± 5.2% in the control group) from T1 (suture removal) to T2 (6 months after implantation) revealed no intergroup differences. The horizontal bone width gain at the implant platform was slightly lower in the experimental group (P < .05). Interestingly, the color-coded figures of both groups showed a facial reduction of grafted material in edentulous areas. However, the apical regions following EMS exhibited stable bone remodeling in the experimental group. CONCLUSION: This novel approach to address the problem involving implant-related surgery close to the periapical lesion of adjacent teeth appeared safe and reliable (no.: ChiCTR2000041153). Int J Oral Maxillofac Implants 2023;38:533-544. doi: 10.11607/jomi.9839.

Cushioned grind-out technique transcrestal sinus floor elevation for simultaneous implantation in severe atrophic maxilla: A retrospective study with up to 7 years of follow-up.

OBJECTIVES: This study aimed to evaluate the effects of the cushioned grind-out technique transcrestal sinus floor elevation for simultaneous implant placement with ≤4 mm of residual bone height (RBH). MATERIALS AND METHODS: This was a retrospective propensity score matching (PSM) study. Five PSM analyses included the confounding variables of Schneiderian membrane perforation, early and late implant failure, and peri-implant apical and marginal bone resorption. After PSM, we compared the difference in five aspects between the RBH ≤ 4 and >4 mm groups. RESULTS: A total of 214 patients with 306 implants were included in this study. After PSM, the generalized linear mixed model (GLMM) indicated that RBH ≤ 4 mm had no significantly higher risk of Schneiderian membrane perforation and early and late implant failure (p = .897, p = .140, p = .991, respectively). The implant cumulative 7-year survival rate of the RBH ≤ 4 and >4 mm groups was 95.5% and 93.9%, respectively (log-rank test: p = .900). Within at least 40 cases per group after PSM, two multivariate GLMMs indicated that RBH ≤ 4 mm could not be identified as the promotive factor of bone resorption of either endo-sinus bone gain or crest bone level (RBH × time interaction p = .850, p = .698, respectively). CONCLUSIONS: Within the limitations, 3 months to 7 years of post-prosthetic restoration review data indicated an acceptable mid-term survival and success rate of applying the cushioned grind-out technique in RBH ≤ 4 mm cases.

Immunomodulatory Biomaterials and Emerging Analytical Techniques for Probing the Immune Micro-Environment.

After implantation of a biomaterial, both the host immune system and properties of the material determine the local immune response. Through triggering or modulating the local immune response, materials can be designed towards a desired direction of promoting tissue repair or regeneration. High-throughput sequencing technologies such as single-cell RNA sequencing (scRNA-seq) emerging as a powerful tool for dissecting the immune micro-environment around biomaterials, have not been fully utilized in the field of soft tissue regeneration. In this review, we first discussed the procedures of foreign body reaction in brief. Then, we summarized the influences that physical and chemical modulation of biomaterials have on cell behaviors in the micro-environment. Finally, we discussed the application of scRNA-seq in probing the scaffold immune micro-environment and provided some reference to designing immunomodulatory biomaterials. The foreign body response consists of a series of biological reactions. Immunomodulatory materials regulate immune cell activation and polarization, mediate divergent local immune micro-environments and possess different tissue engineering functions. The manipulation of physical and chemical properties of scaffolds can modulate local immune responses, resulting in different outcomes of fibrosis or tissue regeneration. With the advancement of technology, emerging techniques such as scRNA-seq provide an unprecedented understanding of immune cell heterogeneity and plasticity in a scaffold-induced immune micro-environment at high resolution. The in-depth understanding of the interaction between scaffolds and the host immune system helps to provide clues for the design of biomaterials to optimize regeneration and promote a pro-regenerative local immune micro-environment.

Horizontal bone augmentation of the edentulous area with simultaneous endodontic microsurgery of the adjacent tooth: A digitally-driven multidisciplinary case report with a 1-year follow-up.

PURPOSE: To introduce a novel and efficient procedure to solve a multidisciplinary issue connected to implant-related surgery in areas near periapical lesions of adjacent teeth using single-stage combined surgery while exploring a new way to prevent retrograde peri-implantitis. MATERIALS AND METHODS: A 31-year-old woman diagnosed with a Kennedy III dentition defect in the maxillary right central incisor and posttreatment apical periodontitis in the maxillary right lateral incisor was treated using a multidisciplinary procedure. First, the preoperative data were collected from intraoral, extraoral facial and CBCT scans. Then, the aesthetic appearance of the anterior teeth was planned digitally and implant insertion was simulated. Next, virtual bone augmentation was carried out with reference to the simulated implant position, and according to the virtual augmentation, the templates for bone shell harvesting (also used for apical osteotomy and root tip resection during endodontic microsurgery) and bone shell grafting of the edentulous area were designed and fabricated. The templates for combined surgery (endodontic microsurgery and horizontal bone augmentation) consisted of one basal template and multiple interchangeable attachments via a plugin design to make guided endodontic microsurgery and digitally guided bone augmentation more efficient. Combined surgery was then carried out using the templates for guidance. During surgery, the apical inflammation affecting the maxillary right lateral incisor was first removed and its preserved apical bony window was prepared as an autogenous bone shell for bone augmentation of the maxillary right central incisor site. Guided bone regeneration of the edentulous area and guided tissue regeneration were then performed for the adjacent tooth. Six months after the combined surgery, digital guided implant surgery was carried out for the edentulous area. The final prosthesis was delivered in accordance with the preoperative aesthetic design and achieved using an implant-supported restoration for the maxillary right central incisor, full crown restoration for the maxillary right lateral incisor, and ceramic veneers for the maxillary left central and lateral incisors for space closure. RESULTS: The horizontal bone augmentation in the edentulous area and endodontic microsurgery on the neighbouring tooth were performed successfully in a single-stage surgical procedure; thus, augmentation of the resorbed alveolar bone and removal of infection in the adjacent site were achieved simultaneously. At the 1-year follow-up after combined surgery, the healing of the natural maxillary right lateral incisor and the area having undergone bone augmentation showed promising results with no postoperative complications. CONCLUSIONS: This novel digital workflow appears effective in addressing the problem of periapical lesions in retained teeth adjacent to the edentulous area that requires horizontal bone augmentation in one surgical procedure, providing an efficient way of resolving the problem using endodontics and implantology, and preventing retrograde peri-implantitis.