Nanodentistry is an emerging field of nanotechnology in order to improvement dental treatment, care and prevention of oral diseases.

Introduction: Enamel subsurface lesions or white spot lesions (WSLs) are commonly found in orthodontic patients with a prevalence of 5% to 97%. Aim: This systematic review aimed to evaluate the efficacy of casein phosphopeptide amorphous calcium phosphate (CPP-ACP) and casein phosphopeptide amorphous calcium phosphate fluoride (CPP-ACPF) for prevention and remineralization of WSLs in orthodontic patients in human randomized controlled clinical trials (RCTs). Methods: Relevant articles were retrieved by searching the Web of Science, Scopus, PubMed, and Cochrane Library databases up to November 2018 with no language or date restriction. The collected data included examination method, groups included in each study with number of patients in each group, study design, follow-up period and summary of important findings of each study. The risk of bias of each study was assessed according to the guidelines of the Cochrane Collaboration's tool. Results: Of 213 articles retrieved, 13 RCTs were included in this systematic review (none of them were included in the meta-analysis). Three articles showed superior efficacy of CPP-ACP for remineralization of WSLs while four studies reported the superior clinical efficacy of CPP-ACPF for this purpose. Conclusion: Both CPP-ACP and CPP-ACPF can decrease the prevalence and increase the remineralization of WSLs during/after orthodontic treatment.

BackgroundOrthognathic surgery includes improvement of morphology and function of occlusion as well as psychological perception and oral health-related quality of life (OHRQoL) of patients. The aim of this study was to determine the OHRQoL of patients with class III skeletal malocclusion before and after orthognathic surgery.Materials and methodsA total of 112 skeletal class III patients including 39 (34.8%) males and 73 (65.2%) females participated in this descriptive quasi-experimental study in three groups: “prior to orthodontic treatment” (n = 25); “under orthodontic treatment and prior to surgery” (n = 65), and “after surgery” (n = 25). All patients filled out a demographic information questionnaire, the oral health impact profile-14 (OHIP-14), and the orthognathic quality of life questionnaire (OQLQ) under the supervision of the examiner. Data were analyzed using ANOVA, independent samples t-test, Mann Whitney test, and Kruskal-Wallis test.ResultsOHRQoL summary score changed from 14.5 prior to orthodontic treatment to 23.4 prior to surgery and during orthodontic treatment to 5.4 after surgery. These OHRQoL changes were statistically significant (P < 0.001).ConclusionsOrthognathic surgery matters to patients with class III skeletal malocclusion and significantly improves their OHRQoL.

Background Considering the increasing popularity of electronic learning, particularly smartphone-based mobile learning, and its reportedly optimal efficacy for instruction of complicated topics, this study aimed to compare the efficacy of smartphone-based mobile learning versus lecture-based learning for instruction of cephalometric landmark identification. Methods This quasi-experimental interventional study evaluated 53 dental students (4th year) in two groups of intervention ( n = 27; smartphone instruction using an application) and control ( n = 26, traditional lecture-based instruction). Two weeks after the instructions, dental students were asked to identify four landmarks namely the posterior nasal spine (PNS), orbitale (Or), articulare (Ar) and gonion (Go) on lateral cephalograms. The mean coordinates of each landmark identified by orthodontists served as the reference point, and the mean distance from each identified point to the reference point was reported as the mean consistency while the standard deviation of this mean was reported as the precision of measurement. Data were analyzed using SPSS version 18 via independent sample t-test. Results No significant difference was noted between the two groups in identification of PNS, Ar or Go ( P > 0.05). However, the mean error rate in identification of Or was significantly lower in smartphone group compared with the traditional learning group ( P = 0.020). Conclusions Smartphone-based mobile learning had a comparable, and even slightly superior, efficacy to lecture-based learning for instruction of cephalometric landmark identification, and may be considered, at least as an adjunct, to enhance the instruction of complicated topics. Trial registration number This is not a human subject research. https://ethics.research.ac.ir/ProposalCertificateEn.php?id=33714&Print=true&NoPrintHeader=true&NoPrintFooter=true&NoPrintPageBorder=true&LetterPrint=true .

Objectives. Retromolar canal (RC) is an anatomic structure, and due to increasing demand for surgical procedure in the retromolar area of the mandible, the identification of the retromolar canal has become an issue of clinical concern. It can innervate the third molar and some of the muscles around the posterior segment of the mandible, complicating surgical procedures in the retromolar area and root canal treatment of third molars. The aim of this study was to evaluate the incidence and anatomical properties of RC in a western Iranian population using cone-beam computed tomography (CBCT) images. Materials and Methods. Two hundred bilateral CBCT images were collected and screened in the three spatial planes for the presence of an RC. Anatomical properties and location of the RCs were assessed according to their course and distance from the surrounding structures. The relationship between the presence of RC and age, sex, side, and presence of second and third molars was also evaluated. Independent samples t-test, ANOVA, Tukey’s post hoc test, paired t-test, and chi-square were used to compare groups. Results. At least one RC was observed in 22% of the mandibles. Its bilateral incidence was 5.5%. Two major types of canals were detected, namely, type I, following a straight or curved course from the mandibular canal (MC) to the retromolar area (47.3%), and type II, coursing from the retromolar area to the radicular part of the third molar (52.7%). Regarding linear measurements, the mean RC diameter and the mean distance to the MC, second, and third molars were 0.68 ± 0.31, 13.7 ± 2.8, 15.3 ± 3.0, and 7.3 ± 2.3 mm, respectively. Conclusion. Based on the results of this study, RC was found in 22% of the cases; thus, it should be considered as a normal anatomical variation in the Iranian population rather than a rare finding.