In oral biology, tissue engineering aims at regenerating functional tissues through a series of key events that occur during alveolar/periodontal tissue formation and growth, by means of scaffolds that deliver signaling molecules and cells. Due to their excellent physicochemical properties and biomimetic features, nanomaterials are attractive alternatives offering many advantages for stimulating cell growth and promoting tissue regeneration through tissue engineering. The main aim of this article was to review the currently available literature to provide an overview of the different nano-scale scaffolds as key factors of tissue engineering for alveolar bone regeneration procedures. In this narrative review, PubMed, Medline, Scopus and Cochrane electronic databases were searched using key words like “tissue engineering”, “regenerative medicine”, “alveolar bone defects”, “alveolar bone regeneration”, “nanomaterials”, “scaffolds”, “nanospheres” and “nanofibrous scaffolds”. No limitation regarding language, publication date and study design was set. Hand-searching of the reference list of identified articles was also undertaken. The aim of this article was to give a brief introduction to review the role of different nanoscaffolds for bone regeneration and the main focus was set to underline their role for alveolar bone regeneration procedures.

Background: The aim of this systematic review was to evaluate the survival rates of immediately loaded implants after at least five years. Besides implant failure, the amount of marginal bone loss around implants and the complication type were assessed. Methods: The electronic search was undertaken on Medline, Scopus, and Cochrane Central Register of Controlled Trials using key terms such as: “immediate loading”, “immediate function”, “immediate restoration”, “immediate temporization”, “dental implants”, “fully edentulous patients”, “partially edentulous patients”. The search terms were combined using the Boolean operators AND, OR. The last electronic search was performed on 15 February 2018. Two authors independently screened the studies, extracted the data, and assessed the risk-of bias. The main outcomes recorded for each study were: implant and prosthesis success and survival, marginal bone level change, incidence and type of complications. Kaplan–Meier analysis was used to estimate cumulative survival rates. Results: Thirty-four prospective studies with at least five-year follow-up, published between 2007 and 2017 were included. A total of 5349 immediately loaded implants in 1738 patients were analyzed. The mean follow-up was 72.4 months (median 60 months, 95% confidence intervals (CI): 64.53, 80.25 months, range 60 to 147 months). The mean weighted implant survival was 97.4% (median 98.15%, 95% CI: 96.29%, 98.54%, range 83.80% to 100%). Cumulative survival rate of implants placed in the mandible was significantly higher than for the maxilla (p < 0.01). No significant difference in failure rate was found among the types of prosthesis employed (p = 0.27). The mean peri-implant bone level change at the end of the follow-up in each study ranged from 0.3 to 1.7 mm. Conclusion: Immediate loading of implants appears to have long-term predictability and success rate under well-defined circumstances.

Background: The aim of this review was to evaluate the adjunctive effect of autologous platelet concentrates (APCs) for the treatment of furcation defects, in terms of scientific quality of the clinical trials and regeneration parameters assessment. Methods: A systematic search was carried out in the electronic databases MEDLINE, SCOPUS, CENTRAL (Cochrane Central Register of Controlled Trials), and EMBASE, together with hand searching of relevant journals. Two independent reviewers screened the articles yielded in the initial search and retrieved the full-text version of potentially eligible studies. Relevant data and outcomes were extracted from the included studies. Risk of bias assessment was also carried out. The outcome variables, relative to baseline and post-operative defect characteristics (probing pocket depth (PPD), horizontal and vertical clinical attachment loss (HCAL, VCAL), horizontal and vertical furcation depth (HFD, VFD) were considered for meta-analysis. Results: Ten randomized trials were included in this review. Only one study was judged at high risk of bias, while seven had a low risk, testifying to the good level of the evidence of this review. The meta-analysis showed a favorable effect regarding all outcome variables, for APCs used in adjunct to open flap debridement (p < 0.001). Regarding APCs in adjunct to bone grafting, a significant advantage was found only for HCAL (p < 0.001, mean difference 0.74, 95% CI 0.54, 0.94). The sub-group analysis showed that both platelet-rich fibrin and platelet-rich plasma in adjunct with open flap debridement, yielded significantly favorable results. No meta-analysis was performed for APCs in combination with guided tissue regeneration (GTR) as only one study was found. Conclusion: For the treatment of furcation defects APCs may be beneficial as an adjunct to open flap debridement alone and bone grafting, while limited evidence of an effect of APCs when used in combination with GTR was found.

Background: Zygomatic implant surgery is considered as a safe and successful alternative to the conventional implant surgery with bone grafts for patients with severe atrophic maxilla. Purpose: The aim of this retrospective clinical case series was to report clinical outcome of zygomatic implants with a follow-up between 6 months and 7 years. Materials and methods: A total of 110 patients with 302 zygomatic implants were included in this study. The intra and postoperative complications and survival rate of zygomatic implants were evaluated. Results: The study included 110 consecutively treated patients with an age range of 21 to 76 years (mean 57.35 years, SD 10.42). The overall zygomatic implant survival rate was 98.34%. There were five implant failures in four patients. One intraoperative and 17 postoperative complications developed in 18 patients. There were no dropouts and the median follow-up of the patients was 41.75 months (with a range of 6-89 months). Conclusions: According to the results, in cases of severely atrophic posterior maxilla, zygomatic implant surgery can be considered as an effective and safe alternative to conventional implants and bone grafting procedures.

Purpose: This prospective study is aimed at investigating clinically and histologically the effectiveness of a biomimetic magnesium-enriched-hydroxyapatite (MgHA)/collagen-based bone substitute for alveolar socket preservation. Materials: Patients scheduled for posterior single tooth extraction were included. The alveolar socket was filled either with MgHA or deproteinized bovine bone matrix (DBBM). In DBBM group, a punch of mucosa was taken from the palate and used to cover the graft. Vertical and horizontal dimensional changes of the alveolar process were assessed clinically with a periodontal probe and with 3-dimensional (3D) analysis of a cast model. Postoperative quality of life was assessed through a questionnaire. After 6 months of healing, an alveolar tissue biopsy was taken for histologic and histomorphometric analysis of the newly formed tissue. After checking normality of the distributions, parametric or nonparametric tests were used for statistical comparisons. Results: Twenty patients (12 males, 8 females, mean age 42.8 ± 5.1 years, range 33–50 years) were treated. After 6 months, vertical and horizontal alveolar ridge resorption was similar in the 2 groups. The 3D analysis of the models showed a significantly higher resorption at the buccal side than at the palatal/lingual side. Histomorphometric analysis showed similar new bone formation for MgHA group (23.07 ± 10.3%) and DBBM (22.77 ± 6.95%), and a significantly higher residual material% for DBBM (15.77 ± 1.95%) than MgHA (5.01 ± 1.04%). Significantly less pain was reported in the first 3 days after surgery in patients of the MgHA group. Conclusion: The MgHA was as safe and effective as DBBM and may represent a feasible bone substitute for alveolar socket preservation.