Refine
Year of publication
- 2021 (8) (remove)
Document Type
- Article (8)
Language
- English (8) (remove)
Has Fulltext
- yes (8)
Is part of the Bibliography
- no (8)
Keywords
- Dental implant (2)
- prevalence (2)
- Biopsy (1)
- Combined surgical therapy (1)
- Immuno‑histochemistry (1)
- Macrophage polarization (1)
- PRF (1)
- Pain management (1)
- Peri-implant disease (1)
- Peri‑implantitis (1)
Institute
- Medizin (8)
Simple Summary: Tooth roots are increasingly applied for bone reconstruction before implant placement. Growth factors stored in the dentin are assumed to enhance bone regeneration, however, the evidence is low. To this aim, collagen membranes were coated with dentin lysates obtained from extracted porcine teeth or remain untreated. The collagen membranes were tested for their capacity to stimulate bone formation in rat calvarial bone defects. After four weeks of healing, micro-computed tomography and histological analyses revealed that dentin lysates coating had no significant impact on the rather strong bone regeneration reaching a nearly complete defect closure even in untreated defects. It can thus be concluded that dentin lysates do not hinder bone regeneration. Conclusions concerning a possible stimulation of bone regeneration by dentin lysates should not be drawn.
Abstract: Autogenous tooth roots are increasingly applied as a grafting material in alveolar bone augmentation. Since tooth roots undergo creeping substitution similar to bone grafts, it can be hypothesized that osteoclasts release the growth factors stored in the dentin thereby influencing bone formation. To test this hypothesis, collagen membranes were either soaked in acid dentin lysates (ADL) from extracted porcine teeth or serum–free medium followed by lyophilization. Thereafter, these membranes covered standardized 5-mm-diameter critical-size defects in calvarial bone on rats. After four weeks of healing, micro-computed tomography and histological analyses using undecalcified thin ground sections were performed. Micro-computed tomography of the inner 4.5 mm calvaria defects revealed a median bone defect coverage of 91% (CI: 87–95) in the ADL group and 94% (CI: 65–100) in the control group, without significant differences between the groups (intergroup p > 0.05). Furthermore, bone volume (BV) was similar between ADL group (5.7 mm3, CI: 3.4–7.1) and control group (5.7 mm3, CI: 2.9–9.7). Histomorphometry of the defect area confirmed these findings with bone area values amounting to 2.1 mm2 (CI: 1.2–2.6) in the ADL group and 2.0 mm2 (CI: 1.1–3.0) in the control group. Together, these data suggest that acid dentin lysate lyophilized onto collagen membranes failed to modulate the robust bone formation when placed onto calvarial defects.
Purpose: To evaluate the efficacy of alternative or adjunctive measures to conventional non-surgical or surgical treatment of peri-implant mucositis and peri-implantitis.
Material and methods: Prospective randomized and nonrandomized controlled studies comparing alternative or adjunctive measures, and reporting on changes in bleeding scores (i.e., bleed0ing index (BI) or bleeding on probing (BOP)), probing depth (PD) values or suppuration (SUPP) were searched.
Results: Peri-implant mucositis: adjunctive use of local antiseptics lead to greater PD reduction (weighted mean difference (WMD) = − 0.23 mm; p = 0.03, respectively), whereas changes in BOP were comparable (WMD = − 5.30%; p = 0.29). Non-surgical treatment of peri-implantitis: alternative measures for biofilm removal and systemic antibiotics yielded higher BOP reduction (WMD = − 28.09%; p = 0.01 and WMD = − 17.35%; p = 0.01, respectively). Surgical non-reconstructive peri-implantitis treatment: WMD in PD amounted to − 1.11 mm favoring adjunctive implantoplasty (p = 0.02). Adjunctive reconstructive measures lead to significantly higher radiographic bone defect fill/reduction (WMD = 56.46%; p = 0.01 and WMD = − 1.47 mm; p = 0.01), PD (− 0.51 mm; p = 0.01) and lower soft-tissue recession (WMD = − 0.63 mm; p = 0.01), while changes in BOP were not significant (WMD = − 11.11%; p = 0.11).
Conclusions: Alternative and adjunctive measures provided no beneficial effect in resolving peri-implant mucositis, while alternative measures were superior in reducing BOP values following non-surgical treatment of peri-implantitis. Adjunctive reconstructive measures were beneficial regarding radiographic bone-defect fill/reduction, PD reduction and lower soft-tissue recession, although they did not improve the resolution of mucosal inflammation.
Peri-implantitis: summary and consensus statements of group 3. The 6th EAO Consensus Conference 2021
(2021)
Objective: To evaluate the influence of implant and prosthetic components on peri-implant tissue health. A further aim was to evaluate peri-implant soft-tissue changes following surgical peri-implantitis treatment. Materials and methods: Group discussions based on two systematic reviews (SR) and one critical review (CR) addressed (i) the influence of implant material and surface characteristics on the incidence and progression of peri-implantitis, (ii) implant and restorative design elements and the associated risk for peri-implant diseases, and (iii) peri-implant soft-tissue level changes and patient-reported outcomes following peri-implantitis treatment. Consensus statements, clinical recommendations, and implications for future research were discussed within the group and approved during plenary sessions. Results: Data from preclinical in vivo studies demonstrated significantly greater radiographic bone loss and increased area of inflammatory infiltrate at modified compared to non-modified surface implants. Limited clinical data did not show differences between modified and non-modified implant surfaces in incidence or progression of peri-implantitis (SR). There is some evidence that restricted accessibility for oral hygiene and an emergence angle of >30 combined with a convex emergence profile of the abutment/prosthesis are associated with an increased risk for peri-implantitis (CR). Reconstructive therapy for peri-implantitis resulted in significantly less soft-tissue recession, when compared with access flap. Implantoplasty or the adjunctive use of a barrier membrane had no influence on the extent of peri-implant mucosal recession following peri-implantitis treatment (SR).
The prevalence of peri-implant diseases around subcrestally placed implants: a cross-sectional study
(2021)
Objectives: To evaluate the prevalence of peri-implant health, peri-implant mucositis or periimplantitis for subcrestally placed implants (1–3 mm) on the short-, medium- and long term.
Material and Methods: Two hundred patients were enrolled in this cross-sectional study that were treated and screened during regular maintenance visits at one university center. A total of 657 implants were evaluated. Peri-implant health and diseases were assessed according to predefined case definitions. Binary logistic regression was used to assess the correlation with local and systemic factors.
Results: After a median function time of 9.36 ± 6.44 years (range: 1–26 years), the prevalence of peri-implant mucositis and peri-implantitis was 66.5% and 15.0%, at the patient level, corresponding to 62.6% and 7.5%, at the implant level, respectively. Peri-implantitis was significantly associated with patients’ history of periodontitis (odds ratio, OR 5.33).
Conclusion: Peri-implant diseases were a common finding around subcrestally placed implants.
Efficacy of platelet-rich fibrin in promoting the healing of extraction sockets: a systematic review
(2021)
Purpose: To address the focused question: in patients with freshly extracted teeth, what is the efficacy of platelet-rich fibrin (PRF) in the prevention of pain and the regeneration of soft tissue and bone compared to the respective control without PRF treatment?
Methods: After an electronic data search in PubMed database, the Web of Knowledge of Thomson Reuters and hand search in the relevant journals, a total of 20 randomized and/or controlled studies were included.
Results: 66.6% of the studies showed that PRF significantly reduced the postoperative pain, especially in the first 1–3 days after tooth extraction. Soft tissue healing was significantly improved in the group of PRF compared to the spontaneous wound healing after 1 week (75% of the evaluated studies). Dimensional bone loss was significantly lower in the PRF group compared to the spontaneous wound healing after 8–15 weeks but not after 6 months. Socket fill was in 85% of the studies significantly higher in the PRF group compared to the spontaneous wound healing.
Conclusions: Based on the analyzed studies, PRF is most effective in the early healing period of 2–3 months after tooth extraction. A longer healing period may not provide any benefits. The currently available data do not allow any statement regarding the long-term implant success in sockets treated with PRF or its combination with biomaterials. Due to the heterogeneity of the evaluated data no meta-analysis was performed.
Objectives: To evaluate peri-implant tissue dimensions following nonsurgical (NS) and surgical therapy (S) employing different decontamination protocols of advanced ligature-induced peri-implantitis in dogs.
Material & Methods: Peri-implantitis defects (n = 5 dogs, n = 30 implants) were randomly and equally allocated in a split-mouth design to NS or S treatment using either an Er:YAG laser (ERL), an ultrasonic device (VUS), or plastic curettes + local application of metronidazole gel (PCM), respectively. Horizontal bone thickness (hBT) and soft tissue thickness (hMT) were measured at different reference points: (v0) at the marginal portion of the peri-implant mucosa (PM); (v1) at 50% of the distance from PM to bone crest (BC); (v2) at the BC; (v3) at the most coronal extension of the bone-to-implant contact. Vertical peri-implant tissue height was calculated from PM to BC.
Results: All of the treatment groups showed a gradual hMT increase from v0 to the v2 reference point, followed by a reduction from v2 to the v3 region. The S-VUS subgroup tended to be associated with higher hMT values at the v0 region than the NS-VUS subgroup (0.44 mm versus 0.31 mm). PM-BC distance varied from 2.22 to 2.83 mm in the NS group, and from 2.07 to 2.38 in the S group.
Conclusion: Vertical and horizontal peri-implant tissue dimensions were similar in different treatment groups.
Aim: To evaluate the efficacy of different types of rehabilitation with fixed or removable full-arch implant-supported prosthesis designs in terms of implant loss and success in patients with at least one edentulous jaw, with tooth loss mainly due to periodontitis.
Materials and methods: Clinical studies with at least 12 months reporting on implant loss and implant success were searched. Meta-analysis was conducted to estimate cumulative implant loss considering different prostheses designs.
Results: A total of 11 studies with unclear to low risk of bias were included in the analysis. Estimated cumulative implant loss for fixed prostheses within 1 year and 5 years was 0.64% (95% confidence interval [CI]: 0.31%–1.31%) and 1.85% (95% CI: 0.85%–3.95%), respectively. The corresponding values for removable prostheses amounted to 0.71% (95% CI: 0.22%–2.28%) and 4.45% (95% CI: 2.48%–7.85%). Peri-implantitis affected 10%–50% of the patients restored with implant-supported fixed prostheses.
Conclusions: Based on the limited low-quality data, the present analysis points to a low and similar cumulative implant loss within 1 year for patients with tooth loss mainly due to stage IV periodontitis restored with either removable or fixed implant-supported full-arch prosthesis. At 5 years of functioning, there was a tendency for better outcomes using fixed designs.
Influence of macrophage polarization on the effectiveness of surgical therapy of peri-implantitis
(2021)
Purpose: To evaluate the influence of macrophage expression and polarization on the effectiveness of surgical therapy of peri-implantitis over a 6 month follow-up.
Methods: A total of fourteen patients (n = 14 implants) diagnosed with peri-implantitis underwent access flap surgery, granulation tissue removal, implantoplasty, and augmentation at intra-bony components using a natural derived bone mineral and application of a native collagen membrane during a standardized surgical procedure. Granulation tissue biopsies were prepared for immunohistochemical characterization and macrophage polarization assessment. M1 and M2 phenotype expression was identified and quantified through immunohistochemical markers and histomorphometrical analyses. Clinical evaluation and data collection were performed initially and after a healing period of 6 months. Statistical analyses were performed to associate infiltrated area, macrophage, and M1/M2 phenotype influence on peri-implant tissue healing parameters after a 6-month follow-up.
Results: Mean infiltrated compartment (ICT) values occupied a total percentage of 70.3% ± 13.0 in the analyzed granulation tissue biopsies. Macrophages occupied a mean area of 15.3% ± 7.0. M1 and M2 phenotypes were present in 7.1 ± 4.1% and 5.5 ± 3.7%, respectively. No statistically significant difference was observed between M1 and M2% expression (p = 0.16). The mean M1/ M2 ratio amounted to 1.5 ± 0.8. Surgical therapy was associated with statistically significant reductions in mean bleeding on probing (BOP), probing depth (PD) and suppuration (SUPP) scores at 6 months (p < 0.05). Linear regression analyses revealed a significant correlation between macrophage expression (CD68%) and changes in PD scores and M1 (%) expression and changes in mucosal recession (MR) scores at 6 months.
Conclusions: The present data suggest that macrophages might influence peri-implant tissue healing mechanisms following surgical therapy of peri-implantitis over a short-term period. Particularly, changes in PD and MR scores were statistically significantly associated with macrophage expression and phenotype.