Changes in sleep and airway variables in patients with obstructive sleep apnea after mandibular advancement splint treatment.

INTRODUCTION: Obstructive sleep apnea (OSA) is an extensive public health problem that imposes considerable morbidity. Mandibular advancement splint (MAS) therapy is a well tolerated treatment, but success rates are difficult to predict. Our objective was to investigate the relationship of oropharyngeal airway dimensions, sleep characteristics, patient biometrics, and treatment response within an OSA patient sample. METHODS: Records of 33 adults were assessed retrospectively with the use of Dolphin 3D and Image J to measure the airway on pretreatment supine cone-beam computed tomography images and derived lateral cephalograms. The patients used Somnodent (Somnomed; Crows Nest, Australia) MAS appliances, which were titrated over 6-8 weeks. Appliance titration measurements and pre- and posttreatment polysomnograms were assessed. Respiratory disturbance index (RDI), absolute and percentage changes in RDI, non-rapid eye movement (NREM) RDI, rapid eye movement (REM) RDI, supine and nonsupine NREM and REM RDI, and minimal blood-oxygen saturation variables were evaluated. The associations of measurements from 2D and 3D minimal anterior-posterior linear distance and 3D airway variables with MAS treatment response were estimated. RESULTS AND CONCLUSIONS: Combined effects of baseline total airway volume, body mass index, neck circumference, location of minimal cross sectional area, and OSA severity were associated with treatment response. Patients with higher initial OSA and more superiorly located airway constriction showed enhanced treatment response to MAS therapy. Airway constriction due to maxillofacial disproportions rather than soft tissue obstruction also showed better treatment response. No significant relationships were found in lateral cephalogram measurements.

Effects of unilateral premolar extraction treatment on the dental arch forms of Class II subdivision malocclusions.

INTRODUCTION: A retrospective study evaluating posttreatment symmetry in dental arch form and midlines was carried out in Class II subdivision patients treated with unilateral and bilateral maxillary premolar extractions. METHODS: Using Geomagic (version 14; Geomagic, Research Triangle Park, NC) and MATLAB (version 8.4; MathWorks, Natick, Mass) software, best-fit curves expressed as quartic polynomials were generated for 13 Class II subdivisions treated with unilateral extractions and 20 treated with bilateral maxillary premolar extractions. Transverse and sagittal measurements were recorded to assess symmetry. Dental models were superimposed on constructed reference planes to generate average posttreatment arches. Statistical comparisons were performed with the significance level set at P ≤0.05. RESULTS: The unilateral extraction group showed significant differences in transverse arch forms between the right and left sides in the anterior, anterior-middle, and middle segments of the arch, and all regions other than the posterior segment in the sagittal dimension. Significant differences were found between groups in the anterior and anterior-middle segments of the arch transversely, the middle and middle-posterior segments sagittally, and the midline deviation relative to the midsagittal plane. Superimposed average arches showed similar results. CONCLUSIONS: Unilateral maxillary extraction treatment generally results in a narrower and more posteriorly displaced arch form on the extraction side, with a deviated maxillary midline toward the extraction side of the arch.

A Proposed Method for Covering a Mini-Screw Head While Maintaining Space for Ligation.

The use of mini-screws, also known as temporary anchorage devices (TADs), to obtain absolute anchorage has become very popular in orthodontics. Nevertheless, potential complications, including traumatic soft tissue lesions, accompany their use. We propose a method to cover the mini-screw head to prevent traumatic soft tissue lesions and promote patient comfort, while maintaining some separation between the composite resin and the peri-implant tissue.

Moving a Blocked-Out Bicuspid into the Arch Using the"Sleeze".

Dental crowding can frequently result in a tooth becoming palatally blocked-out. When the tooth is displaced too far, tying the tooth to the archwire can become unfeasible. A modified "singshot" technique is presented to bring a blocked-out bicuspid into the arch. The lastomeric chain acted as a "sling shot" squeezing the bicuspid in, hence the name "sleeze."

Sleep-Disordered Breathing among Saudi Primary School Children: Incidence and Risk Factors.

This study aimed to identify the incidence and risk factors of sleep-disordered breathing (SDB) using an Arabic version of the pediatric sleep questionnaire (PSQ). A total of 2000 PSQs were circulated to children aged 6-12 years who were randomly selected from 20 schools in Al-Kharj city, Saudi Arabia. The questionnaires were filled out by the parents of participating children. The participants were further divided into two groups (younger group: 6-9 years and older group: 10-12 years). Out of 2000 questionnaires, 1866 were completed and analyzed (93.3% response rate), of which 44.2% were from the younger group and 55.8% were from the older group. Among all the participants, a total of 1027 participants were female (55%) and 839 were male (45%) with a mean age of 9.67 ± 1.78 years. It showed that 13% of children were suffering from a high risk of SDB. Chi-square test and logistic regression analyses within this study cohort showed a significant association between SDB symptoms (habitual snoring; witnessed apnea; mouth breathing; being overweight; and bedwetting) and risk of developing SDB. In conclusion: habitual snoring; witnessed apnea; mouth breathing; being overweight; and bedwetting strongly contribute the to development of SDB.

Multiloop edgewise archwire treatment for a patient with a severe anterior open bite and amelogenesis imperfecta.

Amelogenesis imperfecta is a rare hereditary disorder that affects dental enamel and is often associated with an anterior open bite. Orthodontic treatment of a 16-year-old female patient with hypocalcified amelogenesis imperfecta and a 9-mm anterior open bite was presented. Radiographic examination revealed a steep mandibular plane angle, an increased lower face height, a Class II skeletal pattern, and a convex profile. Additionally, the patient had stainless steel crowns on all upper and lower posterior teeth and composite veneers on the upper anterior teeth. The patient was treated nonsurgically using a multiloop edgewise archwire (MEAW). MEAW mechanics allowed for successful correction of the anterior open bite, with significant reduction in the mandibular plane angle and improvement in the patient's profile. No fixed retainers were used, and the results remained stable 78 months after removal of orthodontic appliances. MEAW mechanics should be considered for patients with large anterior open bites, although this technique requires excellent patient compliance.

Effect of citric acid erosion on enamel and dentin and possible protection by a novel bioactive borate adhesive system.

OBJECTIVES: This study examined the ability of a borate adhesive to protect enamel/dentin surfaces from acidic erosion and its effect on the shear bond strength (SBS) of enamel/dentin to resin composite. MATERIALS AND METHODS: 180 human enamel/dentin specimens were utilized. Enamel buccal surfaces were etched with phosphoric-acid then divided into: (EBG) borate glass adhesive group; (ERS) resin-adhesive system group; (EF) fluoride gel 1.23% group, and enamel control (EC) group; followed by bonding to orthodontic-buttons. The dentin specimens were conditioned by EDTA (Ethylene-diamine-tetra-acetic acid) and divided into: (DBG) borate glass resin, (DRS) resin adhesive; (DDA) group had a dentin-desensitizing agent VivaSens (VivaDent, Liechtenstein) and (DC) control group. The treated enamel/dentin specimens had their SBS to composite. The enamel/dentin specimens were exposed to 1% citric acid (18 min). Enamel/dentin specimens were examined by (SEM/EDS) scanning-electron-microscope equipped with electron-dispersive-spectroscopy and (FTIR/ATR). Analysis-of-Variance (ANOVA) was used to compare the SBS and Wilcoxon-signed-rank test was used to compare the enamel/dentin areas protected by the applied agents before/after erosion (p = 0.05). RESULTS: There was no significance difference in SBS among all groups except for (DDA) group that showed significant decrease p < 0.05. (EBG) and (DBG) groups were the only groups significantly protected enamel and dentin from erosion p < 0.05. FTIR/ATR showed that erosion altered the chemical structure of (DRS), (DDA), and (DC) groups but did not affect the other enamel/dentin groups. Degree of conversion of the borate-adhesive system was acceptable. CONCLUSION: The Borate adhesive system released calcium and phosphate compounds that decreased the erosive activity of the citric acid resulting in protecting simulated dentin-hypersensitive areas and enamel from erosion without affecting the SBS to resin-composite. CLINICAL SIGNIFICANCE: A Borate adhesive system can be adopted as a therapeutic agent in a fully integrated program for protecting dentin-hypersensitive areas and in enamel next to orthodontic fixed appliances.

The use of decorative braces in Jeddah, Saudi Arabia.

OBJECTIVE: To assess the practice of using orthodontic brackets as tooth decorations among dental offices and patients in Jeddah, Saudi Arabia. MATERIALS AND METHODS: The study was a cross-sectional survey using 2 questionnaires. The first included 14 doctor questions where 300 dental offices in Jeddah, Saudi Arabia were contacted by phone. The second questionnaire included 22 patient questions where 50 patients who currently have or have had decorative braces answered the questions online. RESULTS: Out of 250 dental offices that responded, 91 offices (36.4%) answered "yes" to offering decorative braces. Most dentists use metal brackets (96.3%) on both the upper and lower arches (98.8%) and ligate a wire (83.8%) using colored elastomeric ligatures. Out of 50 patients who answered the patient questions, 28 patients (56%) were females and the mean age was 19.84 years (±2.32). 37 (74%) patients reported that their decorative braces were not placed by dentists and mostly by over the counter glue. Finally, 62% reported they were not satisfied, and 84% said they would not recommend getting decorative braces to their family and friends. CONCLUSION: Our results indicate that the use of decorative braces is prevalent, and most are not being placed by dentist. As healthcare providers, we are obliged to educate the public of potential harm that can result when decorative braces are used, to hopefully limit the spread of this unfortunate practice.

Sleep and airway assessment: A review for dentists.

INTRODUCTION: Dentists can be the first professionals to recognize a patient's potential sleep problem since they typically have more frequent contact with their patients than do physicians. It is important that dentists have a reasonable understanding of sleep disorders and how to assess their patients if they suspect such a problem so that a timely referral can be made or treatment can be provided as appropriate. OBJECTIVE: To review the key literature relevant to sleep-disordered breathing (SDB) characteristics and diagnosis, including history, examination, and investigation with an emphasis on radiographic airway analyses. CONCLUSION: The authors present a concise explanation of SDB conditions and an outline for thorough patient examination and evaluation, including radiographic airway analyses. Limited two-dimensional and three-dimensional norms exist for adult patients with no SDB and even less so for children. Much more research is needed, particularly in the pediatric population.

Force decay and dimensional changes of thermoplastic and novel thermoset elastomeric ligatures.

OBJECTIVES: To compare over a period of 8 weeks (1) the force decay and (2) the dimensional changes between thermoplastic (TP) and thermoset (TS) elastomeric ligatures. MATERIALS AND METHODS: TP and TS elastomeric ligatures were obtained from Rocky Mountain Orthodontics™. The TS ligatures were custom made specifically for this study. The sample included 72 clear TP and 72 clear TS elastomeric ligatures. The experiment was performed in a simulated oral environment (pH of 6.75) at 37°C. The remaining forces and the dimensional changes were measured at different time points over a period of 8 weeks. RESULTS: Student's t-tests revealed significant differences in percent force loss, percent change in outer diameter, percent change in inner diameter, and percent change in wall thickness between TP and TS elastomeric ligatures across all time points (P < .001). The difference in percent change in width between TP and TS elastomeric ligatures was not significant at all time points (P > .05). The mean difference in force loss between TP and TS across all time points was 22.91%. The TP and TS specimens exhibited 93.04% and 77.41% force loss, respectively, at the 28th day. CONCLUSIONS: This novel TS elastomeric ligature showed significantly less force decay and dimensional changes over time; therefore, it might be superior during initial leveling and aligning and during finishing stages. Using a transfer jig to prevent relaxation of the specimens before force measurement showed that force decay of commercially available elastomeric ligatures was greater than that described in previous publications.

Force decay evaluation of thermoplastic and thermoset elastomeric chains: A mechanical design comparison.

OBJECTIVES: To compare the following over a period of 8 weeks: (1) force decay between thermoplastic (TP) and thermoset (TS) elastomeric chains; (2) force decay between light (200-g) and heavy (350-g) initial forces; and (3) force decay between direct chains and chain loops (stretched from one pin around the second pin and back to the first pin). MATERIALS AND METHODS: TP and TS chains were obtained from American Orthodontics™ (AOTP, AOTS) and ORMCO™ (OrTP, OrTS). Each of the four chain groups was subdivided into four subgroups with 10 specimens per subgroup: (1) direct chains light force, (2) direct chains heavy force, (3) chain loops light force, and (4) chain loops heavy force. The experiment was performed in artificial saliva (pH of 6.75) at 37°C. RESULTS: A significant difference was found between TP and TS chains, with an average mean difference of around 20% more force decay found in the TP chains (P < .001, α  =  .05). There was no significant difference between direct chains and chain loops except in OrTP, in which direct chains showed more force decay. There was also no significant difference in force decay identified when using light vs heavy forces. CONCLUSIONS: TS chains decayed less than TP chains, and chain loop retraction was beneficial only when using OrTP chains. Contrary to the interchangeable use of TP and TS chains in the published literature and in clinical practice, this study demonstrates that they perform differently under stress and that a clear distinction should be made between the two.