Role of anatomical sites and correlated risk factors on the survival of orthodontic miniscrew implants:a systematic review and meta-analysis

Abstract Objectives The aim of this review was to systematically evaluate the failure rates of miniscrews related to their specific insertion site and explore the insertion site dependent risk factors contributing to their failure. Search methods An electronic search was conducted in the Cochrane Central Register of Controlled Trials (CENTRAL), Web of Knowledge, Scopus, MEDLINE and PubMed up to October 2017. A comprehensive manual search was also performed. Eligibility criteria Randomised clinical trials and prospective non-randomised studies, reporting a minimum of 20 inserted miniscrews in a specific insertion site and reporting the miniscrews’ failure rate in that insertion site, were included. Data collection and analysis Study selection, data extraction and quality assessment were performed independently by two reviewers. Studies were sub-grouped according to the insertion site, and the failure rates for every individual insertion site were analysed using a random-effects model with corresponding 95% confidence interval. Sensitivity analyses were performed in order to test the robustness of the reported results. Results Overall, 61 studies were included in the quantitative synthesis. Palatal sites had failure rates of 1.3% (95% CI 0.3–6), 4.8% (95% CI 1.6–13.4) and 5.5% (95% CI 2.8–10.7) for the midpalatal, paramedian and parapalatal insertion sites, respectively. The failure rates for the maxillary buccal sites were 9.2% (95% CI 7.4–11.4), 9.7% (95% CI 5.1–17.6) and 16.4% (95% CI 4.9–42.5) for the interradicular miniscrews inserted between maxillary first molars and second premolars and between maxillary canines and lateral incisors, and those inserted in the zygomatic buttress respectively. The failure rates for the mandibular buccal insertion sites were 13.5% (95% CI 7.3–23.6) and 9.9% (95% CI 4.9–19.1) for the interradicular miniscrews inserted between mandibular first molars and second premolars and between mandibular canines and first premolars, respectively. The risk of failure increased when the miniscrews contacted the roots, with a risk ratio of 8.7 (95% CI 5.1–14.7). Conclusions Orthodontic miniscrew implants provide acceptable success rates that vary among the explored insertion sites. Very low to low quality of evidence suggests that miniscrews inserted in midpalatal locations have a failure rate of 1.3% and those inserted in the zygomatic buttress have a failure rate of 16.4%. Moderate quality of evidence indicates that root contact significantly contributes to the failure of interradicular miniscrews placed between the first molars and second premolars. Results should be interpreted with caution due to methodological drawbacks in some of the included studies

Prevalence of malocclusion, oral parafunctions and temporomandibular disorder‐pain in Italian schoolchildren: An epidemiological study

Background The prevalence of malocclusion, temporomandibular disorders (TMD) and oral parafunctions is highly debated in children population. Objectives To investigate the prevalence of malocclusion, self-reported oral parafunctions and TMD-pain in Italian schoolchildren and to assess the association between the examined factors. Methods A total of 700 children aged 9-11 years were selected among six public schools in Campania region (Italy). Molar relationship, overjet, overbite and cross-bite were assessed through a clinical examination. Furthermore, the subjects were demanded to fill in a validated questionnaire for TMD-pain screening and the short form of the Oral Behaviours Checklist. Descriptive statistics were used to report the frequencies. The associations between occlusal traits, oral parafunctions and TMD-pain were analysed with a Pearson chi-square test, as expressed by odds ratio and 95% confidence intervals. The significance level was set at P < 0.05. Results Molar Class I was the most frequently encountered molar relationship, followed by molar Class II, subdivision and molar Class III. Increased overjet was more common than negative overjet. Posterior cross-bite was observed in 12% of children. TMD-pain was recorded in 14.7% of subjects. High frequency of oral parafunctions was reported in 21.3% of subjects. A significant association was found between TMD-pain and negative overbite. Cross-bite and high frequency of oral parafunctions were associated with TMD-pain. Conclusion The current results show that malocclusion, self-reported oral parafunctions and TMD-pain are frequent findings among Italian schoolchildren and that some occlusal factors and high frequency of oral parafunctions might be associated with TMD-pain