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Background: Stainless steel (SS) orthodontic brackets may have varying corrosion resistance when used with mouthwashes during orthodontic treatment. Studying their effects on orthodontic brackets will be beneficial. Aim: The study's objective was to analyze the surface characteristics of SS orthodontic brackets and their resistance to corrosion, exposed to chlorhexidine and povidone-iodine mouth rinses - an in vitro and in vivo study. Materials and Methods: The in vitro test: MBT 0.022" slot SS orthodontic brackets were immersed in three groups - Group A - Modified Meyer-Fusayama artificial saliva (AS), Group B - Chlorhexidine, and Group C - Povidone-iodine mouthwash. The in vivo test: Brackets were conventionally bonded on the patient's teeth and divided into Group I - control group, Group II - patients used chlorhexidine, and Group III used povidone-iodine mouth rinse. The corrosion resistance and surface characteristics of SS brackets were determined using scanning electron microscope (SEM), electrochemical impedance spectroscopy, and X-ray photoelectron spectroscopy. Results: Higher corrosion resistance was obtained for brackets immersed in chlorhexidine mouth rinse. The polarization resistance value of the orthodontic SS bracket was 109 MO, 1383 MO, and 769 MO immersed in AS, chlorhexidine, and povidone-iodine mouth rinse, respectively. After surface chemical analysis, XPS data showed the largest intensity peak of metallic chromium (CrO) fresh sample and in the sample immersed in chlorhexidine mouthwash. According to SEM, brackets immersed in chlorhexidine showed a relatively smooth surface. Conclusion: In this study, chlorhexidine was found to be less corrosive followed by povidone-iodine. [ABSTRACT FROM AUTHOR]

Context: Excessive daytime sleepiness (EDS) due to obstructive sleep apnoea (OSA) is reported to be a major contributor to many road traffic accidents. Lack of awareness and diagnosis of OSA among public transport workers remains a threat to the society. Aims: The primary aim of this study was to assess the risk of OSA among transport drivers of south Kerala using modified Berlin questionnaire. The secondary objective included craniofacial assessment of the high-risk patients identified through the questionnaire using lateral cephalogram. Settings and Design: A cross-sectional study was conducted among 180 transport drivers of south Kerala. Methods and Material: Modified Berlin questionnaire and limited physical examination [body mass index (kg/m2), neck circumference (cm), waist circumference (cm), hip circumference and waist to hip ratio, blood pressure (mm Hg)] were recorded. The screened subjects were categorized as high-risk snorers and low-risk snorers based on modified Berlin questionnaire. Craniofacial morphological variations of high-risk group were assessed by lateral cephalograms. Statistical Analysis Used: The descriptive statistics were represented as mean and standard deviation and percentage. Inter-group comparison was performed with independent sample t test. Results: The study demonstrated 64.4% of subjects were non-snorers and 35.6% were snorers. Furthermore, among the snorers, 46.9% were identified as high-risk snorers, whereas the remaining 53.1% represented low-risk snorers. Conclusions: The study revealed the concealed risk of OSA among transport drivers could be screened through the questionnaires and demographics assessment. The application of the proposed screening protocol would triage and enhance safety of OSA affected transport drivers. [ABSTRACT FROM AUTHOR]

Context: Obstructive sleep apnea (OSA) is a condition affecting the upper airway among a vast number of people around the world.Aims: To determine the prevalent risk factors of OSA and its association with craniofacial skeletal pattern.Settings and Design: Cross-sectional, community-based study.Materials and Methods: In the first stage, questionnaire and physical examination were done for 1000 subjects between 20 and 70 years of age. Subjects were categorized as snorers and non-snorers. Snorers were further grouped as high-risk and low-risk snorers. In the second stage, polysomnography (PSG) was done for randomly selected high-risk subjects. Craniofacial skeletal pattern of OSA-diagnosed subjects were compared with non-OSA subjects using lateral cephalograms.Statistical Analysis: Analysis was performed using IBM SPSS 20. Independent sample t-test was used. A P value < 0.05 was considered as statistically significant.Results: The study population represented the following: high-risk snorers: 22.4%, low-risk snorers: 13.9%, and non-snorers: 63.7%. Excessive daytime sleepiness was present in 7.7%. Among high-risk, 80 underwent PSG, and 75 were diagnosed as OSA (94%) and 5 non-OSA subjects. Increased body mass index and neck circumference were statistically significant. Cephalometric evaluation showed difference in maxillomandibular relationship, narrowing of airway space, and inferiorly displaced hyoid.Conclusion: OSA is a major public health problem. Obesity is a strong predictor for OSA. Thus, high-risk subjects for sleep apnea could be identified using routine clinical examination, investigations, and anthropometric parameters. [ABSTRACT FROM AUTHOR]

Objective: The objective of this study was to compare the surface morphology and dimensional stability of the bracket slot at the onset of treatment and after 12 months of intraoral exposure. The study also compared the amount of calcium at the bracket base which indicates enamel loss among the three orthodontic brackets following debonding after 12 months of intraoral exposure. Materials and Methods: The sample consisted of 60 (0.022'' MBT) canine brackets. They were divided into three groups: self-ligating, ceramic bracket with metal slot, and stainless steel (SS) brackets. The slot dimensions, micromorphologic characteristics of as-received and retrieved brackets were measured with a stereomicroscope and scanning electron microscope (SEM), respectively. The amount of calcium at the bracket base which indicates enamel damage was quantified using energy-dispersive X-ray spectrometry (EDX). Results: The results showed statistically significant alterations (P < 0.05) in the right vertical dimension, internal tie wing width (cervical), right and left depth of the slot (Kruskal–Wallis test). Multiple comparison using Mann–Whitney test showed that ceramic brackets underwent (P < 0.05) minimal alterations in the right vertical dimension, internal tie wing width (cervical), right and left depth of the slot (0.01 mm, -0.003 mm, 0.006 mm, -0.002 mm, respectively) when compared with the changes seen in SS and self-ligating brackets. SEM analysis revealed an increase in the surface roughness of ceramic with metal slot brackets and self-ligating bracket showed the least irregularity. The presence of calcium was noted on all evaluated brackets under EDX, but ceramic with metal slot brackets showed a significantly greater amount of enamel loss (P = 0.001). Conclusion: Ceramic brackets were found to be dimensionally stable when compared to SS and self-ligating. Self-ligating bracket showed minimal surface irregularity. Ceramic with metal slot brackets showed a greater amount of enamel loss following debonding. [ABSTRACT FROM AUTHOR]

Background and Objectives: A normal airway is required for the normal growth of the craniofacial structures. The present study was designed to evaluate and compare the airway in Class I and Class II skeletal pattern and to see if there is any association between the airway and maxillomandibular relationship. Materials and Methods: Peripheral nervous system computed tomography scans of 30 patients were divided into two groups as Class I (ANB ≤ 4.5°), Class II (ANB ≥ 4.5°). The Dolphin three-dimensional version 11 was used to assess the airway. Statistical Analysis: Correlations between the variables were tested with the Pearson correlation coefficient. Independent sample t-test was performed to compare the averages between the two groups. P < 0.05 was considered as statistically significant. Results: The ANB angle was negatively correlated with all the airway parameters. The airway area and volume was significantly reduced in Class II subjects compared to Class I. Conclusion: The results suggest a strong association between the airway and skeletal pattern showing a reduced airway in Class II patients with a high ANB angle. [ABSTRACT FROM AUTHOR]

Introduction: oral appliance for the treatment of OSA is considered as an effective, low-risk alternative to CPAP. Demand for oral appliance increases as an alternative for those who cannot tolerate CPAP and refuse surgery. Oral appliances uses the traditional methods to advance the mandible thus modify the posture and their by enlarge the airway or otherwise reduce the collapsibility. Aims and Objectives: The main objective of this study was to evaluate the efficacy of custom made oral appliance on sleep characteristics of OSA patients. Materials and Methods: Polysomnography was done on 15 patients of 24-60 years of age before (T1), and after the delivery of the custom made oral appliance (T2). Statistical Analysis: Paired t tests were performed to determine the significance of change in the polysomnographic and cephalometric variables. P < 0.05 was considered as significant. Results: All patients with oral appliance showed an improvement in sleep parameters with an increase in sleep efficiency, and desaturation index with the use of oral appliance. ESS and cephalometric findings showed improvement in the sleep apnea in concordance with the sleep parameters. Conclusions: Custom made oral appliance is a useful treatment option for improving quality of sleep and can be considered as an alternative treatment modality. [ABSTRACT FROM AUTHOR]

Introduction: Rapid maxillary expansion (RME) is an orthopedic treatment procedure routinely used to treat constricted maxillary arches and also a potential additional treatment in children presenting with sleep-disordered breathing (SDB). Aims and Objectives: The main objective of this study was to evaluate the effects of RME on sleep characteristics in children. Materials and Methods: Polysomnography was done on children of 8-13 years of age before expansion (T0), after expansion (T1) and after a period of 3 months after retention (T2). Bonded rapid maxillary expander was cemented in all children. Inter-molar distance was also measured at T0 and T2. Statistical Analysis: Nonparametric Friedman test was used for comparing the averages of sleep parameters at different time period (T0, T1, T2). Wilcoxon signed ranks test was used for comparing the averages of inter-molar width (T0-T2). P < 0.05 were considered as significant. Results: All children showed an improvement in sleep parameters with an increase in sleep efficiency, decreased in arousal and desaturation index after expansion. Total sleep time showed a statistically significant increase after expansion. A statistically significant increase in inter-molar distance was obtained after expansion. Conclusions: Rapid maxillary expansion is a useful treatment option for improving quality of sleep even in normal children without SDB. It also induces widening of the maxilla, corrects posterior crossbites and improves maxillary and mandibular dental arch coordination. [ABSTRACT FROM AUTHOR]

Objective: To assess the utility of oropharyngeal crowding indicators as predictors of Obstructive Sleep Apnea (OSA)., Methods: STOP-BANG Questionnaire was administered to 145 adults. Of the 95 with high OSA risk, 42 underwent polysomnography. Intraoral space was assessed using modified Mallampati (MMP) and Friedman Scoring (FS) System., Results: Twenty-four were found to have OSA by polysomnography. Most with low risk (86%) had only Class I MMP. Whereas Class III and IV were seen in 37.9% and 17.9% patients with high risk ( p  < .001) and 50% and 20.8% patients with OSA ( p  < .831), respectively. All with low risk had Stage 1 FS. Stages 3 and 4 were observed in 27.4% and 1.1% in the high-risk group ( p  < .001) and in 29.2% and 4.2% with OSA ( p  < .092), respectively., Conclusion: In limited settings, either MMP or FS scores along with the STOP-BANG questionnaire can be used to diagnose OSA.

Background: Temporary anchorage devices or mini-implants have gained great attraction due to its capability to provide absolute anchorage, low cost, versatility, and can be loaded immediately after placement., Aims and Objectives: The aim of this study is to use FEA analysis to assess the strain and insertion torque of mini-implants on a bone model at two distinct angulations of 45° and 90°., Materials and Methods: A computer-aided three-dimensional (3-D) model representing alveolar bone and mini-implants were developed using ANSYS software. Computed tomography scan images of the implant and the alveolar bone were taken and exported in DICOM format for 3-D image processing. The thickness of the bone model is 1 mm. Ti6Al4V orthodontic single and double threaded mini-implants (L = 7 mm, D = 1.5 mm) were inclined at 45° and 90° on to the bone surface to measure the insertion torque and strain produced., Results: Maximum insertion torque (MIT) for single-threaded mini implant at 45° and 90° angulations are 20.001 Nmm and 19.977 Nmm, respectively. MIT for double-threaded mini-implants obtained is 19.977 Nmm at 90° and 19.991 Nmm at 45° angulation. The strain of the bone at 90° angulation for single-threaded mini-implant is 0.00893 mm and for single-threaded mini implant at 45° angulation is 0.01257 mm. The strain in double-threaded mini-implant at 90° angulation is 0.0125 mm and that of 45° angulation is 0.01773 mm., Conclusion: For maximum stability single-threaded mini-implant with perpendicular insertion, angle is preferred., Competing Interests: There are no conflicts of interest., (Copyright: © 2022 Contemporary Clinical Dentistry.)