Epidemiology and risk factors of peri-implantitis: A systematic review

The purpose of this systematic review and meta-analysis was to assess the prevalence, incidence and risk factors of peri-implantitis in the current literature. An electronic search was performed to identify publications from January 1980 until March 2016 on 9 databases. The prevalence and incidence of peri-implantitis were assessed in different subgroups of patients and the prevalences were adjusted for sample size (SSA) of studies. For 12 of 111 identified putative risk factors and risk indicators, forest plots were created. Heterogeneity analysis and random effect meta-analysis were performed for selected potential risk factors of peri-implantitis. The search retrieved 8357 potentially relevant studies. Fifty-seven studies were included in the systematic review. Overall, the prevalence of peri-implantitis on implant level ranged from 1.1% to 85.0% and the incidence from 0.4% within 3 years, to 43.9% within 5 years, respectively. The median prevalence of peri-implantitis was 9.0% (SSA 10.9%) for regular participants of a prophylaxis program, 18.8% (SSA 8.8%) for patients without regular preventive maintenance, 11.0% (SSA 7.4%) for non-smokers, 7.0% (SSA 7.0%) among patients representing the general population, 9.6% (SSA 9.6%) for patients provided with fixed partial dentures, 14.3% (SSA 9.8%) for subjects with a history of periodontitis, 26.0% (SSA 28.8%) for patients with implant function time ≥5 years and 21.2% (SSA 38.4%) for ≥10 years. On a medium and medium-high level of evidence, smoking (effect summary OR 1.7, 95% CI 1.25-2.3), diabetes mellitus (effect summary OR 2.5; 95% CI 1.4-4.5), lack of prophylaxis and history or presence of periodontitis were identified as risk factors of peri-implantitis. There is medium-high evidence that patient's age (effect summary OR 1.0, 95% CI 0.87-1.16), gender and maxillary implants are not related to peri-implantitis. Currently, there is no convincing or low evidence available that identifies osteoporosis, absence of keratinized mucosa, implant surface characteristics or edentulism as risk factors for peri-implantitis. Based on the data analyzed in this systematic review, insufficient high-quality evidence is available to the research question. Future studies of prospective, randomized and controlled type including sufficient sample sizes are needed. The application of consistent diagnostic criteria (eg, according to the latest definition by the European Workshop on Periodontology) is particularly important. Very few studies evaluated the incidence of peri-implantitis; however, this study design may contribute to examine further the potential risk factors.

Alternative reagents to antibodies in imaging applications

Antibodies have been indispensable tools in molecular biology, biochemistry and medical research. However, a number of issues surrounding validation, specificity and batch variation of commercially available antibodies have prompted research groups to develop novel non-antibody binding reagents. The ability to select highly specific monoclonal non-antibody binding proteins without the need for animals, the ease of production and the ability to site-directly label has enabled a wide variety of applications to be tested, including imaging. In this review, we discuss the success of a number of non-antibody reagents in imaging applications, including the recently reported Affimer.

Antibody mimetic receptor proteins for label-free biosensors

Small synthetic antibody mimetic receptor proteins which offer high stability, specificity and affinity are presented as capture molecules in solid-state electro-chemical biosensors.

Molecular and clinicopathological analysis of Epstein-Barr virus-associated posttransplant smooth muscle tumors

Epstein-Barr virus (EBV)-associated posttransplant smooth muscle tumors (PTSMT) are very rare complications. We aimed to provide a clinicopathological characterization which is based on our own case series (n = 5) as well as previously reported PTSMT cases (n = 63). Meta-analysis of PTSMT and molecular analysis of tumor cells from our cohort was performed. Most PTSMT developed in kidney-transplanted patients (n = 41/68, 60%). Liver/transplant liver was the main site of manifestation (n = 38/68, 56%). Tumors occurred after a median interval of 48 months (range 5-348) and developed earlier in children than in adults. Most tumors showed no marked cellular atypia, low mitosis rate and no tumor necrosis. Gene expression analysis of 20 EBV-related genes, including two microRNAs, revealed overexpression of MYC (p = 0.0357). Therapy was mainly based on surgical resection or reduced immunosuppression but no significant differences in overall survival were evident. Lower overall survival was associated with multiorgan involvement (n = 33/68, 48.5%) and particularly with intracranial PTSMT manifestation (n = 7/68, 10%; p < 0.02), but not transplant involvement (n = 11/68, 16%). In summary, PTSMT differ from conventional leiomyosarcomas by their lack of marked atypia, unusual sites of involvement and defining EBV association. Surgery and reduced immunosuppression show comparable clinical results and prognosis is associated with intracranial manifestation.