The enigma of sleep: Implications of sleep neuroscience for the dental clinician and patient.

BACKGROUND: Sleep disturbances have been shown to result in considerable morbidity and mortality. It is important for dental clinicians to understand the neuroscience behind sleep disorders. TYPES OF STUDIES REVIEWED: The authors conducted a search of the literature published from January 1990 through March 2024 of sleep medicine-related articles, with a focus on neuroscience. The authors prioritized articles about the science of sleep as related to dental medicine. RESULTS: The authors found a proliferation of articles related to sleep neuroscience along with its implications in dental medicine. The authors also found that the intricate neuroscientific principles of sleep medicine are being investigated robustly. The salient features of, and the differences between, central and obstructive sleep apneas have been elucidated. Sleep genes, such as CRY, PER1, PER2, and CLOCK, and their relationship to cancer and neurodegeneration are also additions to this rapidly developing science. CONCLUSIONS AND PRACTICAL IMPLICATIONS: The dental clinician has the potential to be the first to screen patients for possible sleep disorders and make prompt referrals to the appropriate medical professionals. This can be lifesaving as well as minimize potential future morbidity for the patient.

An In Vivo Study on the Development of Bacterial Microbiome on Clear Orthodontic Retainer.

OBJECTIVES: The objective of this study was to see how the bacterial composition changes on clear orthodontic retainer over a 14-day period. METHODS: Saliva and plaque samples collected from a clear retainer surface were obtained from five healthy volunteers receiving retainer treatment. Prior to clear retainer delivery, patients had not been wearing any other appliances. Patients were instructed to wear their clear retainer for the 14-day period, taking them off to eat and to clean them with a soft-bristle toothbrush. The bacterial composition was determined via Illumina MiSeq sequencing of the bacterial 16S rRNA. After bioinformatics processing using the QIIME pipeline, the intra- and intergroup biodiversity of the sample was analyzed. RESULTS: The bacterial composition changed over a 14-day period in the saliva and on the clear retainer. When comparing the different phylum levels between saliva and clear retainer' microbiota, the Firmicutes were significantly increased 1.26-fold (p = 0.0194) and 1.34-fold (p = 0.0123) after 7 and 14 days of retainer treatment when compared to saliva, respectively. The Campylobacteriota were significantly decreased 1.80-fold (p = 0.05) in the clear retainer when compared to saliva at 7 days. At the genus level, several microbiota were significantly increased in relative abundance in the clear retainer after the 14-day period. CONCLUSION: These findings reveal that the presence of a clear retainer in the mouth might lead to enamel changes or periodontal tissue destruction, especially after 14 days of use.

Class II correction in orthodontic patients utilizing the Mandibular Anterior Repositioning Appliance (MARA).

OBJECTIVES: To evaluate skeletal and dentoalveolar changes produced by the Mandibular Anterior Repostioning Appliance (MARA) in the treatment of Class II malocclusion in adolescent patients. MATERIALS AND METHODS: Lateral cephalograms of 24 patients, mean age 12.40 years, with a Class II malocclusion consecutively treated with MARA were compared with a historical control group. Changes were evaluated using the Pancherz superimposition and grid analysis pre- and posttreatment. Independent sample t-test, Mann-Whitney U-test, and Pearson correlation coefficient analysis were performed. RESULTS: Significant differences were seen between the treatment and control groups during the 12 month period. Improvement in Class II relationship in the MARA group resulted from skeletal and dentoalveolar changes. There was a 7-mm molar correction and a 4.7-mm overjet reduction. There was also an increase in the mandibular base of 3.3 mm with the lower molar and incisor coming forward 2.6 mm and 2.2 mm, respectively. No significant headgear effect was shown on the maxilla. The maxillary incisor position remained unchanged, whereas the molar distalized 1.8 mm. The anterior lower facial height had an overall increase of 2.2 mm. CONCLUSIONS: The MARA was successful in achieving a Class I molar relationship and reducing the overjet in Class II malocclusions. This was the result of both skeletal and dentoalveolar changes.

Clinical evaluation of fiber-reinforced-plastic bonded orthodontic retainers.

INTRODUCTION: This clinical study was designed to evaluate the efficacy of innovative fiber-reinforced-thermoplastic (FRP) bonded orthodontic retainers. METHODS: Anterior lingual retainers were formed by using a 2-step process from preimpregnated unidirectional long glass fibers (volume fraction, 0.25) in a thermoplastic resin matrix of either poly(ethylene terephthalate glycol) or polycarbonate. Seventy-six canine-to-canine retainers were placed in 56 patients by using the acid-etch technique over a 34-month period. They were evaluated for clinical acceptability to function as a retainer, structural integrity of the FRP, and integrity of the bonding. Variables examined included material composition, design factors, and mechanism of failure of the retainers. The results were analyzed by using the univariate Kaplan-Meier survival method and the multivariate Cox regression model. RESULTS: The overall median survival time was 7.6 months, with 33% surviving after 12 months. The retainer with the longest service was in use for over 24 months. The variables with the most significant effects and improved survival rates were FRP formulation (polycarbonate), retainer thickness (1.02 mm), and number of teeth overlapped (all 6 teeth). Failure was primarily due to bond failure at the enamel-adhesive or adhesive-FRP interface. CONCLUSIONS: With improved survival times, FRP retainers could be a viable alternative to metal retainers.

Characteristics of applicants who obtain interviews at orthodontic postgraduate programs.

OBJECTIVE: To evaluate applicant credentials that are associated with receiving interviews to postgraduate orthodontic programs. MATERIALS AND METHODS: Twenty-two variables incorporating academic, work, and personal characteristics of 68 applicants were analyzed using a mailed questionnaire survey and data from application files. Applicants were grouped into categories based on the number of interviews reported. RESULTS: Statistically significant associations were identified between interview category and: age, number of programs applied to, grade in orthodontic course, grade point average, scores from part 1 of the national dental board exam, academic honors, research, recommendation letter from orthodontic faculty, general practice residency, work experience, and community service. CONCLUSIONS: Programs are interested in rounded, well-balanced individuals who excel at more than one thing. Cumulative grade point average and orthodontic work experience were the most significant.

Colour changes of orthodontic elastomeric module materials exposed to in vitro dietary media.

OBJECTIVE: To evaluate the colour stability of orthodontic elastomeric module material exposed to dietary media. DESIGN: An in vitro laboratory study. MATERIALS AND METHODS: Coloured and clear orthodontic elastomeric modules from four companies were exposed to coffee, cola, tea and spices for 72 h. The difference in colour components was measured with a Minolta chromameter before and after exposure. RESULTS: Significant changes in colour, including grey level and chromaticity, both as a function of colour and company of elastomeric ligature module were found following exposure to beverages and spices. Colour change was most affected by Deltab* (yellowness) and most significant in clear modules. Modules made using injection mouldings were more resistant to colour change than those by extrusion. Spice mix had the most effect and cola beverage the least. Clinically, these changes compromised both colour stability and esthetics of the elastomeric module. CONCLUSIONS: Clinicians should make patients aware of the effect of consuming beverages and spices on the colour stability of their selected ligature modules. Clinicians should favour modules made with injection moulding. Darker colour modules may be preferred to clear modules to avoid excessive colour degradation through dietary media such as beverages and food spices. Patients consuming large amounts of spices or coffee should avoid clear modules made by extrusion processing because of their tendency to discolour.