International journal of oral implantology (Berlin, Germany)最新文献

Purpose: The goal of soft tissue augmentation is to improve the volume around implants and thus achieve better aesthetic and functional properties. The present review aims to make recommendations and guide clinicians in performing soft tissue augmentation procedures, focusing on the importance of timing.

Overview: Soft tissue augmentation can be performed at different time points: before or after implant placement, at implant placement (immediate/delayed), at healing abutment connection or after final restoration. Before/after implant placement or at healing abutment connection are considered the gold standard time points at which to perform soft tissue augmentation due to the possibility of achieving complete coverage of the soft tissue graft or its substitute through simple flap elevation and the easy handling of tissue. On the other hand, performing soft tissue augmentation at implant placement or after crown delivery seems to be less predictable due to the different healing approaches and the unexpected shrinkage that occurs.

Conclusion: Timing needs to be considered when performing soft tissue augmentation, taking into account the advantages and disadvantages related to operator experience, implant position and patient expectations. Employing a reliable approach at the appropriate time of intervention could limit complications.

Zygomatic implant-supported rehabilitation has grown in popularity for use in clinical practice. Although many studies have been carried out into the surgical procedure, the prosthetic workflow is not clearly defined and standard techniques are not readily applied; thus, a digital approach may ultimately streamline the procedure. In the present study, the authors examined a digital workflow for immediately loaded prostheses supported by zygomatic implants. The novel technique proposed by the present authors, involving use of an impression reference, achieved promising results in terms of accuracy and procedural simplification.

Purpose: Guided bone regeneration is a widely used technique for the treatment of atrophic arches. A broad range of devices have been employed to achieve bone regeneration. The present study aimed to investigate the clinical and histological findings for a new titanium CAD/CAM device for guided bone regeneration, namely semi-occlusive titanium mesh.

Materials and methods: Nine partially edentulous patients with vertical and/or horizontal bone defects underwent a guided bone regeneration procedure to enable implant placement. The device used as a barrier was a semi-occlusive CAD/CAM titanium mesh with a laser sintered microperforated scaffold with a pore size of 0.3 mm, grafted with autogenous and xenogeneic bone in a ratio of 80:20. Eight months after guided bone regeneration, surgical and healing complications were evaluated and histological analyses of the regenerated bone were performed.

Results: A total of 9 patients with 11 treated sites were enrolled. Two healing complications were recorded: one late exposure of the device and one early infection (18.18%). At 8 months, well-structured new regenerated trabecular bone with marrow spaces was mostly present. The percentage of newly formed bone was 30.37% ± 4.64%, that of marrow spaces was 56.43% ± 4.62%, that of residual xenogeneic material was 12.16% ± 0.49% and that of residual autogenous bone chips was 1.02% ± 0.14%.

Conclusion: Within the limitations of the present study, the results show that semi-occlusive titanium mesh could be used for vertical and horizontal ridge augmentation. Nevertheless, further follow-ups and clinical and histological studies are required.

Purpose: To evaluate the survival of and incidence of mechanical complications with single- and multiple-unit cement-retained posterior implant-supported restorations with custom CAD/CAM Atlantis titanium abutments (Dentsply Sirona, Charlotte, NC, USA).

Materials and methods: This retrospective clinical study analysed 196 Astra Tech OsseoSpeed TX Internal Hexagon implants (Dentsply Sirona) placed in 85 patients between January 2011 and January 2021. Customised Atlantis titanium abutments and cement-retained metal-ceramic crowns were employed. The clinical outcomes recorded were implant and abutment survival rates, and mechanical complications. The results were analysed according to implant length and diameter, arch, implant position and single- or multiple-unit restoration.

Results: Over the observation period (up to 10 years), implant and abutment survival rates were 98.5% and 100.0%, respectively. The mean observation period for the single- and multiple-unit implant-supported restorations was 106.00 ± 20.84 months, with a minimum of 41 months and a maximum of 120 months. For the 67 single-unit and 129 multiple-unit posterior implant-supported restorations, four mechanical complications were recorded: two cases of screw loosening, one case of chipping or fracture of veneering materials, and one case of crown decementation. No screw or abutment fractures were observed.

Conclusions: According to the results of this retrospective clinical study, cement-retained posterior implant-supported restorations with custom CAD/CAM Atlantis titanium abutments showed high survival rates over a follow-up period of up to 10 years. No statistically significant differences were recorded when comparing implant position, implant diameter, implant length, single- versus multiple-unit restoration and arch.

Purpose: To describe a fully digital workflow for an implant-supported fixed hybrid restoration that involves a double CAD/CAM structure and to highlight the benefits of this type of restoration.

Materials and methods: Using a fully digital workflow, starting from intraoral scans, the necessary steps for producing the final hybrid prosthesis are described. The prosthesis consists of a titanium primary structure and a zirconia secondary structure that is cemented onto the primary structure in the laboratory. A clinical case is presented to illustrate the steps required for prosthetic rehabilitation.

Results: This technique enables the fabrication of clinically valid and passive prostheses using a fully digital workflow.

Conclusion: In just three clinical sessions, a fully digital workflow makes it possible to produce robust implant-supported fixed hybrid prostheses, comprising a titanium primary structure and an outer secondary structure made of zirconia. This procedure can be applied to a wide range of cases from simple to extended, including full-arch restorations.

Purpose: To determine the histological effects of ultraviolet light and cold atmospheric plasma treatment on the osseointegration of titanium implants in vivo.

Materials and methods: Six juvenile pigs were divided into three groups of two animals each. A total of 54 titanium implants were placed randomly in the pigs' calvarial bone (nine implants per pig). Of these, 18 implants served as untreated controls. The remaining 36 implants served as the experimental group and were treated with either ultraviolet light or argon plasma for 12 minutes each prior to insertion. Two pigs in each group were kept until 2, 4 and 8 weeks and then sacrificed. Resonance frequency analysis was conducted after implant placement and at the time of sacrifice. Osseointegration was evaluated using microcomputed tomography scans and histomorphometrical analysis.

Results: After initial loss, all implants showed a constant increase in implant stability quotient values over time without significant differences between the groups. The bone-implant contact values increased steadily for all implants over 8 weeks of healing. Surface-treated implants showed significantly higher bone-implant contact values compared to untreated implants at each time point. Bone area fraction occupancy values were almost always higher following both treatment methods; however, differences were only significant after 4 and 8 weeks for the cold atmospheric plasma group and after 4 weeks for the ultraviolet light group.

Conclusions: Ultraviolet light and cold atmospheric plasma may improve histomorphometrical osseointegration of titanium implants significantly.

The following amendments are made to the published article: Int J Oral Implantol (Berl) 2023;16(2): 117-132; First published 9 May 2023.

Background: Studies on different surgical approaches have been published with excellent success rates for zygomatic implants. The same publications offer different results regarding the complications associated with the use of such implants. A consensus protocol on zygomatic implant interventions has yet to be documented.

Purpose: To seek to establish a consensus at each step of treatment consisting of oral rehabilitation using zygomatic implant-anchored restorations, and to share the outcome of the process to serve as a basis for practitioners and researchers.

Materials and methods: A wide variety of protocols were identified based on the results of a literature review conducted previously. All participants received the results of the systematic literature search. A modified Delphi process was used to establish a consensus protocol. Six sections were defined: Diagnosis and indications, Planning, Medication, Surgery, Prosthesis, and Follow-up. The first round of 17 open-ended questions was shared with 63 participants, all of whom were experts in zygomatic implant rehabilitation and part of the ZAGA Centers network. A total of 77 follow-up questions were then generated after analysis of the responses to the first 17 questions.

Results: Of the 63 experts enrolled, 48 responded to both rounds of questions. Consensus was determined based on the percentage of agreement: < 70% was considered "no consensus" and ≥ 70% was considered "consensus". A high level of consensus was reached. The sections with the lowest percentage of agreement were Medication and Surgery, where a consensus was reached for 67% of the questions. Of the questions included in the Follow-up section in both rounds, a consensus was reached for 80%. Overall, agreement was obtained on 71% of the topics.

Conclusions: Use of the modified Delphi process led to the creation of the first consensus protocol for oral restorations anchored to zygomatic implants.

Purpose: To longitudinally assess the prevalence of peri-implant health, peri-implant mucositis and peri-implantitis in a cohort of patients with and without history of periodontitis over a 20-year period.

Materials and methods: Eighty-four patients who attended a specialist private periodontal practice were evaluated prospectively 10 and 20 years after prosthesis delivery. Following successful completion of periodontal/implant therapy, patients (172 implants) were enrolled on an individualised supportive periodontal care programme. Clinical and radiographic parameters were collected to assess the prevalence of peri-implant health and diseases. Prevalence of peri-implantitis and peri-implant mucositis was calculated based on the case definition set out in 2018. A multilevel logistic regression analysis was conducted to assess potential risk or protective factors.

Results: The analysis was performed on 22 periodontally healthy and 62 periodontally compromised patients rehabilitated with 39 and 130 implants, respectively. The 10-year prevalence of peri-implant health, peri-implant mucositis and peri-implantitis was 21.4%, 67.9% and 10.6%, respectively, whereas the 20-year prevalence was 29.8%, 47.6% and 33.3%, respectively. Non-compliant periodontally compromised patients showed a statistically significantly increased risk at 20 years of both peri-implant mucositis (odds ratio 11.1; 95% confidence interval 1.8-68.6) and peri-implantitis (bone loss and probing depth) (odds ratio 14.3; 95% confidence interval 1.8-32.9). High full-mouth plaque and bleeding scores were associated with higher odds of both peri-implant mucositis and peri-implantitis.

Conclusions: Peri-implant diseases were prevalent in patients rehabilitated with dental implants and followed up for a period of 20 years. History of periodontal disease and a lack of compliance with a tailored supportive periodontal care programme were identified as risk factors for peri-implant diseases.