Despite decades of titanium as the gold standard in oral implantology, the search for alternatives has been growing. High esthetic standards and increasing incidence of titanium allergies, along with a rising demand for metal‐free reconstructions, have led to the proposal of ceramics as potential surrogates. Following numerous experimental studies, zirconium dioxide (zirconia) has earned its place as a potential substitute for titanium in implantology. Yet, despite zirconia's excellent biocompatibility and tissue integration, low affinity to plaque and favorable biomechanical properties, early failures were significantly higher for zirconia implants than for titanium implants. Technical failure as a result of fracture of the material is also a major concern. So far, zirconia implants have been mainly manufactured as one‐piece implant systems because of the material's limitations. Nevertheless, various two‐piece systems have been progressively emerging with promising results. Screw‐retained abutments are desirable but present a major technical challenge. Innovation and technical advances will undoubtedly lead to further improvement in the reliability and strength of zirconia implants, allowing for novel designs, connections and reconstructions. Additional clinical studies are required to identify all relevant technical and biological factors affecting implant success and patients’ satisfaction. However, the evidence for a final verdict is, at present, still incomplete.

Objectives To compile the current evidence regarding the association between the release of titanium particles and biologic complications of dental implants. Material and methods This is a critical review. We searched the literature using the terms “corrosion,” “allergy,” “hypersensitivity,” or “particles” together with “titanium,” “Ti,” “TiO2.” The bibliographies of identified publications and previously published review articles were scanned to find additional related articles. We included clinical studies, in vivo and in vitro experiments. Results Titanium particles and degradation products of titanium have been detected in oral and nonoral tissues. Particles are released from surfaces of dental implants because of material degradation in a process called tribocorrosion. It involves mechanical wear and environmental factors, notably contact to chemical agents and interaction with substances produced by adherent biofilm and inflammatory cells. In vitro, titanium particles can interfere with cell function and promote inflammation. A temporal association between exposure to titanium and occurrence of tissue reactions suggested hypersensitivity in a limited number of cases. However, there is poor specificity as the observed reactions could be initiated by other factors associated with the placement of implants. Titanium particles are commonly detected in healthy and diseased peri‐implant mucosa alike, at low levels even in gingiva of individuals without titanium implants. Rather than being the trigger of disease, higher concentrations of titanium in peri‐implantitis lesions could be the consequence of the presence of biofilms and inflammation. Conclusion There is an association between biocorrosion, presence of titanium particles, and biological implant complications, but there is insufficient evidence to prove a unidirectional causal relationship.

ObjectivesThe aim of this review was to evaluate the clinical success and survival rates of zirconia ceramic implants after at least 1 year of function and to assess if there is sufficient evidence to justify using them as alternatives to titanium implants.Materials and methodsAn electronic search in MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Clinical Trials (CENTRAL) databases was performed in April 2015 by two independent examiners to retrieve clinical studies focusing on the survival rate of zirconia implants after at least 1 year of function. Implant survival was estimated using the overall proportion reported in the studies with a Clopper-Pearson 95 % confidence interval (random effect model with a Der-Simonian Laird estimate).ResultsFourteen articles were selected out of the 1519 titles initially screened. The overall survival rate of zirconia one- and two-piece implants was calculated at 92 % (95 % CI 87–95) after 1 year of function. The survival of implants at 1 year for the selected studies revealed considerable heterogeneity.ConclusionsIn spite of the unavailability of sufficient long-term evidence to justify using zirconia oral implants, zirconia ceramics could potentially be the alternative to titanium for a non-metallic implant solution. However, further clinical studies are required to establish long-term results, and to determine the risk of technical and biological complications. Additional randomized controlled clinical trials examining two-piece zirconia implant systems are also required to assess their survival and success rates in comparison with titanium as well as one-piece zirconia implants.Clinical relevanceZirconia implants provide a potential alternative to titanium ones. However, clinicians must be aware of the lack of knowledge regarding long-term outcomes and specific reasons for failure.

Objectives Bleeding on gentle probing (BOP) is the key parameter to the diagnosis of mucositis, while changes in crestal bone levels, along with clinical signs of inflammation, are required for the diagnosis of peri‐implantitis. This systematic review and meta‐analysis focused on the evaluation of BOP as a predictive measure for peri‐implantitis. Materials and methods An electronic search was performed through Medline and EMBASE databases, followed by a hand search through previous reviews and reference lists. Screening, study selection, data extraction and evaluation of publication bias were conducted by two independent examiners. Clinical studies reporting on the prevalence of peri‐implantitis, BOP and/or suppuration (SUP) after more than 1 year of functional loading were selected. Meta‐analyses were conducted to combine the proportions of peri‐implantitis among BOP‐ and/or SUP‐positive subjects and implants across studies. Subgroups were created and compared to investigate potential sources of heterogeneity. Results Thirty‐one studies were selected for analysis. Inconsistent definitions of peri‐implantitis were reported across the studies. Twenty‐nine studies reported data on implant‐level and twenty publications reported on subject‐level. The combined proportion of peri‐implantitis was 24.1% (95% CI 19.3–29.7) in BOP‐positive implants and 33.8% (95% CI 26.7–41.6) for BOP‐positive cases. However, the degree of variability among studies was high; the prediction intervals were 10.3‐69.3 and 6.9‐57.8, respectively. Evidence of asymmetry or publication bias could not be statistically detected. Short observation periods were significantly associated with lower proportions of peri‐implantitis among BOP‐positive implants. Conclusions For BOP‐positive implants, there was a 24.1% chance to be diagnosed with peri‐implantitis; while for BOP‐positive patients, there was a 33.8% probability to be diagnosed with peri‐implantitis. This probability varied across study populations. Clinicians should be aware of the considerable false‐positive rate of BOP to diagnose peri‐implantitis.

Objectives: Working Group 5 was assigned the task to review the current knowledge in the area of digital technologies. Focused questions on accuracy of linear measurements when using CBCT, digital vs. conventional implant planning, using digital vs.conventional impressions and assessing the accuracy of static computer-aided implant surgery (s-CAIS) and patient-related outcome measurements when using s-CAIS were addressed. Materials and methods:The literature was systematically searched, and in total, 232 articles were selected and critically reviewed following PRISMA guidelines. Four systematic reviews were produced in the four subject areas and amply discussed in the group. After emendation, they were presented to the plenary where after further modification, they were accepted.Results: Static computer-aided surgery (s-CAIS), in terms of pain & discomfort, economics and intraoperative complications, is beneficial compared with conventional implant surgery. When using s-CAIS in partially edentulous cases, a higher level of accuracy can be achieved when compared to fully edentulous cases. When using an intraoral scanner in edentulous cases, the results are dependent on the protocol that has been followed. The accuracy of measurements on CBCT scans is software dependent. Conclusions:Because the precision intraoral scans and of measurements on CBCT scans and is not high enough to allow for the required accuracy, s-CAIS should be considered as an additional tool for comprehensive diagnosis, treatment planning, and surgical procedures. Flapless s-CAIS can lead to implant placement outside of the zone of keratinized mucosa and thus must be executed with utmost care. K E Y W O R D Saccuracy, computer-aided surgery, cone beam computed tomography, intraoral scans, oral implantology, patient-reported outcome measures sidering standardized conditions, and (b) it is crucial to address the software version and used scan protocol for further studies to create a reliable database for accurate statistical analyses.Although in clinical practice, single unit restorations are being performed using a digital workflow, there is a need for further research to conclude if it is a predictable and reliable procedure when compared to the conventional workflow.• There is a lack of literature about the accuracy of different intraoral scan bodies in terms of geometry, dimension, material, and surface characteristics. More studies regarding these aspects should be conducted.• In studies using scan bodies, design, and characteristics should be defined to make studies comparable.• Regarding multiple implant-supported restorations for partially dentate or edentulous cases, different scanning protocols should be developed and compared.The influence of distance between scan bodies, length and geometry of the edentulous span, mucosal morphology, and on the accuracy of digital impressions should be studied.The aim of this systematic review was to identify studies that assessed the accuracy of linear measurements of bone dimensions related to implant...