Three-dimensional changes to the upper airway after maxillomandibular advancement with counterclockwise rotation: a systematic review and meta-analysis.

The aim of this study was to evaluate the effect of counterclockwise (CCW) rotation and maxillomandibular advancement (MMA) on the upper airway space using three-dimensional images. An electronic search was performed in the PubMed, Cochrane Library, Scopus, Virtual Health Library, Web of Science, and OpenGrey databases (end date July 2016); a hand-search of primary study reference lists was also conducted. The inclusion criteria encompassed computed tomography evaluations of the upper airway spaces of adult patients undergoing orthognathic surgery with CCW rotation and MMA. The articles were evaluated for risk of bias with a tool for before-and-after studies. A meta-analysis was performed with the mean differences using a random-effects model. Heterogeneity was assessed with the Q-test and the I2 index. The meta-analysis revealed significant (P<0.001) increases in both the total airway volume (effect size of 6832mm3 and confidence interval of 5554-8109mm3) and the minimum axial area (effect size of 92mm2 and confidence interval of 70-113mm2). The heterogeneity was low in both comparisons (I2=38% and 7%, respectively). The technique of mandibular advancement with CCW rotation produced significant increases in the volumes and areas of the upper airway spaces.

How do geometry-related parameters influence the clinical performance of orthodontic mini-implants? A systematic review and meta-analysis.

The aim of this systematic review and meta-analysis was to investigate how parameters related to geometry influence the clinical performance of orthodontic mini-implants (MIs). Systematic searches were performed in electronic databases including MEDLINE, Scopus, Web of Science, Virtual Health Library, and Cochrane Library and reference lists up to March 2016. Eligibility criteria comprised clinical studies involving patients who received MIs for orthodontic anchorage, with data for categories of MI dimension, shape, and thread design and insertion site, and evaluated by assessment of primary and secondary stability. Study selection, data extraction, quality assessment, and a meta-analysis were carried out. Twenty-seven studies were included in the qualitative synthesis: five randomized, eight prospective, and 14 retrospective clinical studies. One study with a serious risk of bias was later excluded. Medium and short MIs (1.4-1.9mm diameter and 5-8mm length) presented the highest success rates (0.87, 95% CI 0.80-0.92). A maximum insertion torque of 13.28Ncm (standard error 0.34) was observed for tapered self-drilling MIs in the mandible, whereas cylindrical MIs in the maxilla presented a maximum removal torque of 10.01Ncm (standard error 0.17). Moderate evidence indicates that the clinical performance of MIs is influenced by implant geometry parameters and is also related to properties of the insertion site. However, further research is necessary to support these associations.

Bone Density and Clinical Periodontal Attachment in Postmenopausal Women: A Systematic Review and Meta-Analysis.

Osteoporosis is a systemic skeletal disease characterized by low bone mineral density (BMD) and has been considered a risk factor for periodontal disease. The aim of this systematic review and meta-analysis was to verify the scientific evidence for the association of periodontal attachment loss with low BMD in postmenopausal women. A systematic search of the literature was performed in databases until August 2016, in accordance with Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) guidelines. Eligibility criteria included studies that compared clinical attachment loss (CAL) between postmenopausal women with low and normal BMD. Studies using similar methodology, with lower and higher risk of bias, were pooled into 3 different meta-analyses to compare CAL among women with normal BMD, osteoporosis, and osteopenia. In the first meta-analysis, mean CAL was compared among groups. In the other 2 meta-analyses, the mean percentages of sites with CAL ≥4 mm and ≥6 mm were respectively compared among groups. From 792 unique citations, 26 articles were selected for the qualitative synthesis. Eleven of the studies were appraised as presenting low risk of bias, and the association between low BMD and CAL was observed in 10 of these studies. Thirteen cross-sectional articles were included in the meta-analysis for osteoporosis and 9 in the osteopenia analysis. Women with low BMD presented greater mean CAL than those with normal BMD (osteoporosis = 0.34 mm [95% confidence interval (CI), 0.20-0.49], P < 0.001; osteopenia = 0.07 mm [95% CI, 0.01-0.13], P = 0.02). Only studies with lower risk of bias were available for the analysis of CAL severity. Women with low BMD presented more severe attachment loss, represented as mean percentage of sites with CAL ≥4 mm (osteoporosis = 3.04 [95% CI, 1.23-4.85], P = 0.001; osteopenia = 1.74 [95% CI, 0.36-3.12], P = 0.01) and CAL ≥6 mm (osteoporosis = 5.07 [95% CI, 2.74-7.40], P < 0.001). This systematic review and meta-analysis indicates that postmenopausal women with osteoporosis or osteopenia may exhibit greater CAL compared with women with normal BMD.

Is resin infiltration an effective esthetic treatment for enamel development defects and white spot lesions? A systematic review.

OBJECTIVES: To determine if resin infiltration is an effective treatment for improving the esthetic appearance of tooth discoloration resulting from development defects of enamel (EDD) and white spot lesions (WSL) by means of a systematic review. DATA SOURCES: A comprehensive search was performed in PubMed, Scopus, Web of Science, LILACS, BBO Library, Cochrane Library, and SIGLE, as well as in the abstracts of IADR conference, and in the clinical trials registry. STUDY SELECTION: Clinical studies in patients with whitish tooth discoloration, in which the resin infiltration technique was applied, were included. Color masking was the primary outcome. The methodological quality and risk of biases of included papers was assessed using MINORS criteria for non-randomized (NRS) comparative studies and Cochrane Collaboration for randomized clinical trials (RCT). RESULTS: From a total of 2930 articles, 17 were assessed for eligibility and 11 remained in the qualitative synthesis. Four NRS and seven RCT studies were selected, the latter consisting of four full-text studies and three conference abstracts. Two studies were excluded from the quality assessment, due to overlapping results. The number of participants (treated teeth) ranged from 18 to 21 (38-74) in the NRS, and 20-83 (20-231) in the RCT studies. Post-orthodontic WSL were the most frequent treated lesions. Initial condition was used as control in the NR studies. In the RCT, resin infiltration was compared to non treatment, remineralization, or bleaching. Overall, partial or complete color masking of affected teeth was reported immediately after resin infiltration. Only two studies followed original outcomes up to one year and reported maintenance of original color masking. Two NR studies were assessed as "moderate" and one as "high" quality. Two RCT were classified as "low" risk of bias in the chosen key domains. The remaining four studies were considered "unclear" or "high" risk of bias. CONCLUSION: Although the partial or total masking effect of enamel whitish discoloration has been shown with resin infiltration, there is no strong evidence to support this technique based on the present clinical studies. CLINICAL SIGNIFICANCE: Enamel whitish discolorations in esthetically compromised areas are clinically undesirable. Minimally invasive approaches used as attempts to minimize the discoloration include the resin infiltration technique. The evidence for clinical recommendation of this technique is not strong, thus, further RCT studies with long-term follow-ups should be conducted.

Effects of age, sex, and odours from conspecific adult males on ultrasonic vocalizations of infant CS1 mice.

Young CS1 mice aged 2, 4, 6, 8 and 10 days were each sequentially exposed to odours of urine from strange adult infanticidal and non-infanticidal males and the number of ultrasonic vocalizations monitored. There was a clear age effect, with pups 6-8 days calling the most. For pups of 2 and 6 days of age there were significant positive correlations between body weight and number of calls but for 10-day-old pups a negative correlation was found. Female pups called more than males, particularly when exposed to odours but this was not due to body weight. Overall, more calls were produced when odours from infanticidal rather than non-infanticidal males were presented and individual pups altered their ultrasonic output as the odours were changed.

The transition from optional to required subjects.

We propose (contra Hyams, 1986) that the optional subject phenomenon in early child language arises because children have not yet acquired the morphological elements (primarily modals and tense) necessary to distinguish Subject-Taking (ST) verbs (e.g. finite verbs) from their non-Subject-Taking (NST) counterparts (e.g. infinitives). Unaware of this distinction, children are able only to observe that verbs sometimes occur with subjects and sometimes without. We show that our proposal makes a number of developmental predictions which we then test with the help of longitudinal data from three children. We conclude that: (1) There is no systematic morphological distinction between ST and NST verbs during the optional subject stage (OSS). (2) The emergence of the distinction between ST and NST verbs is gradual rather than sudden. (3) There is variation from child to child in terms of which morphologically-defined subclass of verbs is first recognized as subject-taking. (4) There is no link between the emergence of modals or contracted copulas and the end of the OSS.