International Journal of Oral Implantology, 03/2021

Purpose: To investigate whether implant position (adjacent to teeth/implants vs most distal position in the arch) influences the clinical outcomes of short (≤ 6 mm) non-splinted implants.  Materials and methods: A systematic electronic search of human randomised clinical trials and prospective cohort studies was performed using the PubMed, Embase and Cochrane Central Register of Controlled Trials (Central) databases. A manual search of implant-related journals was also performed. A meta-analysis was conducted to compare survival rate, marginal bone loss and prosthetic complications based on implant position.  Results: Overall, 11 studies were included to give a total of 388 non-splinted short implants (269 adjacent, 119 distal) followed up over a period ranging from 12 to 120 months. No significant differences in survival were found when comparing adjacent and distal positioning for both arches, and no significant differences were found for marginal bone loss or prosthetic complications between groups regardless of position.  Conclusions: Short implants supporting single crowns presented similar outcomes when placed in the most distal position in the arch or between adjacent teeth or other implants. Conflict-of-interest statement: The authors do not have any financial interests, either direct or indirect, in the products mentioned in the present study. Keywords: dental implants, occlusal loading, short implants, single crown

Purpose: To provide an up to date, contemporary and concise evidence-based review of peri-implant diseases and conditions and discuss the current therapeutic approaches to managing these diseases. Materials and methods: A literature review was conducted focusing on peri-implant health, peri-implant mucositis and peri-implantitis, as described according to the 2017 World Workshop on the Classification of Periodontal and Peri-implant Diseases and Conditions. Results and conclusions: Peri-implant health is described when there are no clinical signs of inflammation, and when no further bone loss after physiological remodelling or increase in probing depth can be observed. Peri-implant mucositis is a reversible inflammatory lesion that affects the soft tissues surrounding a dental implant in the absence of radiographic bone loss, whereas peri-implantitis is an irreversible pathological condition affecting the hard and soft tissues around an osseointegrated dental implant. Clinical diagnosis of peri-implant disease is in some ways similar to that of periodontitis, but their prevalence varies significantly due to many confounding variables. Different treatment modalities have been proposed and tested in the literature; as yet, however, no standard treatment protocol has been proven superior or completely effective. In future research, well-designed studies are required to assess treatment responses and evaluate additional approaches that may lead to improved outcomes. Conflict-of-interest statement: The authors do not have any financial interests, either direct or indirect, in the companies whose materials are mentioned in this study. Keywords: complications, dental implant, disease, maintenance, peri-implant mucositis, peri-implant tissues, peri-implantitis, periodontitis, review, surgical, therapy

Purpose: To investigate the effect of platelet-rich fibrin on bone formation by investigating its use in guided bone regeneration, sinus elevation and implant therapy. Materials and methods: This systematic review and meta-analysis were conducted and reported in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The eligibility criteria comprised human controlled clinical trials comparing the clinical outcomes of platelet-rich fibrin with those of other treatment modalities. The outcomes measured included percentage of new bone formation, percentage of residual bone graft, implant survival rate, change in bone dimension (horizontal and vertical), and implant stability quotient values. Results: From 320 articles identified, 18 studies were included. Owing to the heterogeneity of the investigated parameters, a meta-analysis was only possible for sinus elevation. There is a general lack of data from comparative randomised clinical trials evaluating platelet-rich fibrin for guided bone regeneration procedures (only two studies), with no quantifiable advantages in terms of new bone formation or dimensional bone gain found in the platelet-rich fibrin group. For sinus elevation, the meta-analysis demonstrated no advantage in terms of histological new bone formation in the control group (bone graft alone) compared with the test group (bone graft and platelet-rich fibrin). Two studies demonstrated that platelet-rich fibrin may shorten healing periods prior to implant placement. Platelet-rich fibrin was also shown to slightly enhance primary implant stability (implant stability quotient value < 5) as assessed using implant stability quotients and resonance frequency analysis parameters, with no histological data evaluating bone–implant contact yet available on this topic. In one study, platelet-rich fibrin was shown to improve the clinical parameters when utilised as an adjunct for the treatment of peri-implantitis. Conclusions: In the majority of studies, platelet-rich fibrin offered little or no clear advantage in terms of new bone formation as evaluated in various studies on guided bone regeneration and sinus elevation, nor in implant stability and treatment of peri-implantitis. Various authors and systematic reviews on the topic have now expressed criticism of the various study designs and protocols, and the lack of appropriate controls and available information regarding patient selection. Well-controlled human studies on these specific topics are required. Conflict-of-interest statement: Richard J Miron holds intellectual property on platelet-rich fibrin. All other authors declare no conflicts of interest. Keywords: biomaterials, bone graft, growth factors, platelet-rich fibrin, platelet concentrates

Purpose: To assess hard and soft tissues regenerated around immediate implants placed in compromised fresh extraction sockets using vestibular socket therapy 2 years postoperatively. Materials and methods: Twenty-seven compromised fresh extraction sockets were managed using vestibular socket therapy and immediate implant placement. After immediate implant placement, a cortical bone shield was stabilised through a vestibular incision. The socket defect was filled with particulate bone graft. Labial plate thickness and bone height were evaluated 1 and 2 years postoperatively using CBCT. The pink aesthetic score and probing depth were recorded after 6 months, 1 year and 2 years. A Friedman test was used to study changes in the reported outcomes over time, with the level of statistical significance set at P ≤ 0.05. Results: All implants recorded a 100.0% survival rate. A statistically significant increase in bone height (0.93 mm, P = 0.004) and apical (0.12 mm, P = 0.026), midfacial (1.26 mm, P < 0.001) and crestal (0.86 mm, P < 0.001) bone thickness was observed after 2 years. The changes in pink aesthetic score and probing depth were not significant: the pink aesthetic score was 12.48 ± 1.45 and the mean PD was 2.37 ± 0.79 mm mesially, 2.11 ± 0.70 mm facially, 2.07 ± 1.04 mm distally and 1.00 ± 0.00 mm palatally after 2 years. Conclusion: Combining immediate implant placement with vestibular socket therapy to manage compromised fresh extraction sockets offers promising radiographic, aesthetic and periodontal results while minimising the treatment time and number of surgical procedures required. Conflict-of-interest statement: None of the authors have any commercial relationships to declare. The present research was totally self-funded. Keywords: aesthetics, bone graft, extraction socket, guided bone regeneration, immediate placement, vestibular socket therapy

Purpose: Simplified and predictable immediate single-tooth replacement therapy can be optimised by leveraging recent advances in digital workflows that combine static surgical guidance and customised prosthesis design and fabrication. The present case report illustrates a novel approach to successfully executing immediate single-tooth replacement therapy via static computer-aided immediate implant placement and digital provisionalisation utilising angulated screw access, with a 1-year follow-up after delivery of the definitive restoration. Materials and methods: A healthy 27-year-old woman with congenital agenesis of the mandibular second premolars and who required replacement of the mandibular left second premolar underwent immediate single-tooth replacement therapy via computer-aided, restrictive implant placement and provisionalisation using custom prosthetic components designed prior to the surgical intervention being performed. Results: After a 6-month healing period, the provisional crown was replaced with the definitive restoration. After 1 year, the peri-implant keratinised mucosa demonstrated vertical gain in the mid-buccal portion and stability in the interproximal aspects, and no changes in marginal bone level were observed. Conclusions: The present case report demonstrates the successful application of novel digital tools to facilitate both surgical and prosthetic aspects of immediate single-tooth replacement therapy. Digital workflows can optimise the clinical efficiency and predictability of tooth replacement therapy with dental implants by reducing surgical and restorative chair time and increasing patient satisfaction. Conflict-of-interest statement: The authors declare there are no conflicts of interest relating to this study. Keywords: CAD/CAM, computer-aided surgery, dental implant, digital dentistry, guided implant surgery, immediate loading, immediate placement, prosthetic procedure, prosthodontics