Upper airway morphology in adults with positional obstructive sleep apnea.

PURPOSE: To compare the anatomical balance and shape of the upper airway in the supine position between adults with positional obstructive sleep apnea (POSA) and adults with non-positional OSA (NPOSA). METHODS: Adults diagnosed with OSA (apnea-hypopnea index (AHI) > 10 events/h) were assessed for eligibility. POSA was defined as the supine AHI more than twice the AHI in non-supine positions; otherwise, patients were classified as NPOSA. Cone beam computed tomography (CBCT) imaging was performed for every participant while awake in the supine position. The anatomical balance was calculated as the ratio of the tongue size to the maxillomandibular enclosure size. The upper airway shape was calculated as the ratio of the anteroposterior dimension to the lateral dimension at the location of the minimal cross-sectional area of the upper airway (CSAmin-shape). RESULTS: Of 47 participants (28 males, median age [interquartile range] 56 [46 to 63] years, median AHI 27.8 [15.0 to 33.8]), 34 participants were classified as having POSA (72%). The POSA group tended to have a higher proportion of males and a lower AHI than the NPOSA group (P = 0.07 and 0.07, respectively). After controlling for both sex and AHI, the anatomical balance and CSAmin-shape were not significantly different between both groups (P = 0.18 and 0.73, respectively). CONCLUSION: Adults with POSA and adults with NPOSA have similar anatomical balance and shape of their upper airway in the supine position. TRIAL REGISTRATION: This study was registered with the Australian New Zealand Clinical Trials Registry (ANZCTR Trial ACTRN12611000409976).

A comparative assessment of the dentoskeletal effects of clear aligners vs miniplate-supported posterior intrusion with fixed appliances in adult patients with anterior open bite. A multicenter, retrospective cohort study.

INTRODUCTION: This study aimed to retrospectively evaluate the dentoskeletal effects of clear aligners (Invisalign) vs miniplate-supported posterior intrusion (MSPI) and identify factors associated with posttreatment overbite in adults with anterior open bite. METHODS: Twenty-nine patients treated with Invisalign and 24 with MSPI combined with full-fixed orthodontic appliances were included from 5 orthodontic practices. Pretreatment and posttreatment lateral cephalometric measurements were included as outcomes. Comparisons across groups and identification of final overbite predictors were assessed with regression modeling and machine learning techniques. RESULTS: MSPI induced significantly greater maxillary molar intrusion (1.5 mm; 95% confidence interval [CI], 0.83-2.17; P <0.001), with subsequent reduction of anterior face height (ANS-Me) (-2.77 mm; 95% CI, -3.64 to -1.91; P <0.001), Mp-SN° (-1.95°; 95% CI, -2.77 to -1.12; P <0.001), and ANB° (-1.69°; 95% CI, -2.44 to -0.94; P <0.001) compared with Invisalign. MSPI resulted in a significantly larger increase in SNB° (0.94°; 95% CI, 0.23-1.65; P = 0.01) and point-Pog projection (2.45 mm; 95% CI, 1.12-3.77; P = 0.001). Compared with MSPI, Invisalign had a significantly greater increase in the distance of maxillary (1.05 mm; 95% CI, 0.38-1.72; P = 0.003) and mandibular (0.9 mm; 95% CI, 0.19-1.60; P = 0.01) incisal edges relative to their apical bases, with borderline greater lingual tipping of only the maxillary incisors (2.82°; 95% CI, -0.44 to 6.09; P = 0.09). Appliance type and initial overbite were significant final overbite predictors across all models. However, this difference was only evident in male patients (males [1.65; 95% CI, 0.99-2.32; P <0.001]; female [-0.04; 95% CI, -0.52 to 0.44; P = 0.87]). CONCLUSIONS: Both appliances effectively improve overbite. MSPI applied the correction via molar intrusion and counterclockwise mandibular autorotation, whereas Invisalign via maxillary and mandibular incisor extrusion.

Physical properties of root cementum: Part 28. Effects of high and low water fluoridation on orthodontic root resorption: A microcomputed tomography study.

INTRODUCTION: Transient inflammatory surface resorption, referred to as orthodontic induced inflammatory root resorption (OIIRR), is an iatrogenic consequence of orthodontic tooth movement. Systemic fluoride has been associated with a reduction of OIIRR. This study aimed to investigate the effects of water fluoridation levels on OIIRR in a clinically applicable human orthodontic model. METHODS: Twenty-eight patients who required bilateral maxillary first premolar extraction as part of orthodontic treatment were selected from 2 cities with high and low water fluoridation of ≥2 ppm and ≤0.05 ppm, respectively. Patients were separated into high fluoride (HF) and low fluoride (LF) groups on the basis of water fluoridation levels. Bilateral maxillary first premolar teeth were subjected to 150 g of buccal tipping forces for 12 weeks with reactivation every 4 weeks. Teeth were extracted at the end of 12 weeks. Root resorption crater volume was determined using microcomputed tomography and 3-dimensional reconstruction. RESULTS: HF group showed significantly less mean root resorption volume on the palatal root surface when compared with the LF group (P = 0.025). This difference was specifically displayed at palatal apical regions (P = 0.041). When root resorption volumes from the zones of orthodontic pressure (buccal cervical, palatal apical) were combined, the mean difference between HF and LF groups was statistically significant (P = 0.045). CONCLUSIONS: Findings of the present study indicated a positive correlation between water fluoridation and the reduction of OIIRR, especially at the zones of orthodontic pressure, using a clinically relevant human orthodontic model.

Australian Orthodontists Utilization and Attitude Toward a Government Funded Cleft Scheme.

OBJECTIVES: To (1) survey Australian orthodontists about their involvement with a government-funded scheme for patients with clefts, the Medicare Cleft Lip and Cleft Palate Scheme (MCLCPS) and (2) investigate their attitude toward treating patients with clefts and their training in this respect. DESIGN: A 13-question online survey was distributed to members of the Australian Society of Orthodontists. The survey gathered information regarding respondent demographics, the number of MCLCPS-eligible patients seen in the past 12 months and usual billing practices. RESULTS: A total of 96 complete responses were obtained. About 70% of respondents had treated MCLCPS-eligible patients in the past 12 months and 55% saw between 2 and 5 patients during this time. The likelihood of treating patients with clefts increased by a factor of 4.8 (95% CI: 1.2-18.9) if practicing outside of a capital city and 1.5 times for each decade increase in orthodontist's age (95% CI: 1.0-2.2). The MCLCPS was utilized by 81% of orthodontists with 26% of these respondents accepting rebate only. Most orthodontists felt their university training could have better prepared them to treat patients with clefts. A minority of orthodontists felt that a rebate increase would make them more likely to treat these patients. CONCLUSIONS: Australian orthodontists who treat patients with clefts tend to be older and work outside of capital cities. The decision to treat these patients tends to not be financially motived. Specialty orthodontic training programs could improve the preparedness of their graduates to treat patients with clefts.

Effect of light-emitting diode-mediated photobiomodulation on extraction space closure in adolescents and young adults: A split-mouth, randomized controlled trial.

INTRODUCTION: This split-mouth trial aimed to examine the effects of light-emitting diode (LED)-mediated photobiomodulation compared with no photobiomodulation on maxillary canine distalization. METHODS: Twenty participants (10 males and 10 females; aged 11-20 years) requiring bilateral extraction of maxillary first premolars were included from the Sydney Dental Hospital waiting list. After premolar extractions, leveling, and alignment, canines were retracted on 0.020-in stainless steel wires with coil springs delivering 150 g of force to each side. Each patient's right side was randomly assigned to experimental or control using www.randomisation.com, and allocation concealment was performed with sequentially numbered, opaque, sealed envelopes. The experimental side received 850 nm wavelength, 60 mW/cm2 power, continuous LED with OrthoPulse device (Biolux Research Ltd, Vancouver, British Columbia, Canada) for 5 min/d. For the control side, the device was blocked with opaque black film. Patients were reviewed at 4-week intervals for force reactivation and intraoral scanning over 12 weeks. The primary outcome was the amount of tooth movement, and secondary outcomes were anchorage loss and canine rotation, all measured digitally. Blinding for study participants and the treating clinician was not possible; however, blinding was done for the measurements by deidentifying the digital scans. Linear mixed models were implemented for the data analysis. RESULTS: Nineteen participants concluded the study. Data analysis showed that the treatment × time interaction was not significant, suggesting no difference in space closure (unstandardized regression coefficient [b], 0.12; 95% confidence interval [CI], -0.05 to 0.29; P = 0.17), canine rotation (b, 0.21; 95% CI, -0.82 to 1.25; P = 0.69), and anchorage loss (b, -0.01, 95% CI, -0.28 to 0.26, P = 0.94). No harms were noted. CONCLUSIONS: Daily 5-minute application of LED did not result in clinically meaningful differences during extraction space closure compared with no LED application. REGISTRATION: Australian New Zealand Clinical Trials Registry (ACTRN12616000652471). PROTOCOL: The protocol was not published before trial commencement. FUNDING: This research was funded by the Australian Society of Orthodontists Foundation for Research and Education.

Trends in the choice of a clinician for orthodontic treatment in the United States.

INTRODUCTION: This study evaluated the trends in orthodontic practitioner choice over the past 15 years and explored the lay public's understanding of different orthodontic practitioner options in the U.S., specifically, orthodontists compared with general dentists. METHODS: A survey was distributed to a representative sample of laypersons in the U.S. The response rate was 90.2%, and 727 completed responses were analyzed. RESULTS: A 28.2% shift away from orthodontists toward general dentists over the last 15 years was significant (P <0.001). The 2 most frequently endorsed ways respondents found their orthodontic practitioners were a recommendation from another dentist (54.2%) and their family's general dentist who offered orthodontic treatment in-house (22.9%). Respondents' knowledge of orthodontists was limited; 85.0% believed that dentists who perform orthodontic treatment are also orthodontic specialists. Only 17.1% of respondents disagreed with the statement that "a dentist who advertises orthodontic treatment is an orthodontic specialist." In addition, 89.7% were not aware that a dentist could not be called an orthodontist without separate training from an accredited residency program. Finally, 64.2% of respondents did not know that an orthodontist must complete more education than a general dentist. CONCLUSIONS: Over the past 15 years, the percentage of orthodontic patients treated by general dentists has increased significantly. The public's ability to differentiate between different types of orthodontic practitioners is poor, showing substantial confusion about orthodontists' qualifications. Most respondents believed that orthodontists are best suited for their orthodontic treatment, but they rely heavily on their general dentists for orthodontic practitioner decisions.

Effects of rapid and slow maxillary expansion on root resorption: a micro-computed tomography study.

AIM: To compare root resorption (RR) after rapid maxillary expansion (RME) and slow maxillary expansion (SME) through micro-computed tomography (micro-CT). SUBJECTS AND METHODS: Twenty-six subjects who required maxillary expansion and bilateral upper first premolar extraction were randomly assigned to RME (n = 13, mean age: 13.25 ± 0.88 years) or SME (n = 13, mean age: 13.53±1.28 years) group. A hyrax-type acrylic bonded expansion appliance was used. The Hyrax screw was activated » turn twice a day for 20 days in the RME group and » turn every second day for 80 days in the SME group. One randomly selected upper first premolar was extracted in each patient after active expansion. The appliance was left in situ for a 24-week retention period then the contralateral upper first premolar was extracted. Extracted teeth were scanned with micro-CT and the volume of the resorption craters was analysed with a specialized software. Transversal skeletal and dental widths were measured on posteroanterior radiographs taken before and after expansion and retention periods. RESULTS: The resorption craters were concentrated mostly on the buccal surface and middle level in all samples. The total RR in the RME group was less post-expansion (P ≤ 0.05) and more post-retention (P > 0.05) than the SME group. During retention, there was a significant decrease in the total RR in the SME group (P > 0.05) and an increase in the RME group. Both RME and SME groups displayed a similar increase in skeletal transverse dimensions, but inter-molar width increased significantly more in the SME group during the whole experimental period. CONCLUSION: RME does not have an advantage over SME in terms of skeletal expansion and the amount of RR when a retention period of six months is followed.

The upper airway volume effects produced by Hyrax, Hybrid-Hyrax, and Keles keyless expanders: a single-centre randomized controlled trial.

OBJECTIVE: To assess upper airway volume changes after rapid maxillary expansion (RME) with three different expanders. TRIAL DESIGN: Three-arm parallel randomized clinical trial. METHODS: Sixty-six patients, 10-16 years old, in permanent dentition, with maxillary transverse deficiency were recruited and assigned with block randomization (1:1:1 ratio) and allocation concealment to three groups of 22 patients each (Hyrax, Hybrid-Hyrax, and Keles keyless expander). The primary outcome (overall upper airway volume change) and secondary outcomes (volume changes in the nasal cavity, nasopharynx, oropharynx, and hypopharynx) were blindly assessed on the initial (T0) and final (T1, 6 months at appliance removal) cone beam computed tomography. Differences across groups were assessed with crude or adjusted for confounders (gender, age, growth stage, skeletal pattern, baseline airway volume, and amount of expansion) linear regression models. RESULTS: Fifty-one patients were analysed (19, 19, and 13 in the Hyrax, Hybrid-Hyrax, and Keles groups). Maxillary expansion resulted in considerable increases in total airway volume in the Hybrid-Hyrax group (+5902.1 mm3) and less in the Hyrax group (+2537.9 mm3) or the Keles group (+3001.4 mm3). However, treatment-induced changes for the primary and all secondary outcomes were of small magnitude and no significant difference was seen among the three expanderes in the total airway volume in either crude or adjusted analyses (P > 0.05 in all instances). Finally, among pre-peak patients (CVM 1-3), the Hybrid-Hyrax expander was associated with significantly greater increases in total airway volume compared to the Hyrax expander (P = 0.02). CONCLUSIONS: RME resulted in relatively small increases in total upper airway volume and its separate compartments, with mostly no statistically significant differences across the Hyrax, Hybrid-Hyrax, and Keles groups. LIMITATIONS: Significantly greater attrition was found in the Keles group due to appliance failure. The current trial might possibly be under-powered to detect differences between groups, if such exist. HARMS: Keles expanders blocked during activations and required substitution for completion of treatment. PROTOCOL: The protocol was not published before trial commencement. REGISTRATION: Australian and New Zealand Clinical Trial Registry (ACTRN12617001136392).

Published evidence regarding association between malocclusion and orthodontic treatment on oral health is inconclusive.

ARTICLE TITLE AND BIBLIOGRAPHIC INFORMATION: Macey R, Thiruvenkatachari B, O'Brien K, Batista KBSL. Do malocclusion and orthodontic treatment impact oral health? A systematic review and meta-analysis. Am J Orthod Dentofacial Orthop. 2020;157(6):738-744.e10. doi:10.1016/j.ajodo.2020.01.015. SOURCE OF FUNDING: Government: Public Health England or the National Health Service. TYPE OF STUDY/DESIGN: Systematic review with meta-analysis of data.

The effects of a clinically feasible application of low-level laser therapy on the rate of orthodontic tooth movement: A triple-blind, split-mouth, randomized controlled trial.

INTRODUCTION: This split-mouth trial aimed to investigate the effect of low-level laser therapy (LLLT) on the amount of maxillary canine distalization when applied every 4 weeks over 12 weeks. METHODS: Twenty-two adolescents and young adults (15 female, 7 male; aged 13-25 years; n = 22) requiring bilateral maxillary first premolar extractions were recruited. After extractions and leveling-alignment, canines were retracted using closed-coil nickel-titanium springs delivering 150 g of force. LLLT was applied to 8 intraoral points on the buccal and palatal sides around the canine root for 10 seconds per point, on day 0, 28, and 56 with the control side receiving sham application. Alginate impressions were taken every 4 weeks on day 0, 28, 56, and 84. The amount of tooth movement, anchorage loss, and canine rotation were measured digitally. Randomization was generated using www.randomisation.com and allocation concealment through sequentially numbered, opaque, sealed envelopes. Participants, operator, and statistic assessor were blinded. Linear regression modeling accounting for clustering within each patient was used to identify differences between LLLT and control sides. RESULTS: Twenty-one patients completed the study. The total amount of tooth movement was similar in the LLLT (2.55 ± 0.73 mm) and control group (2.30 ± 0.86 mm), whereas 0.25 mm (95% confidence interval, -0.21, 0.71 mm) of difference was insignificant (P = 0.27). No significant differences were found for anchorage loss (P = 0.22) or canine rotation (P = 0.25). No harms were reported. CONCLUSIONS: Application of LLLT every 4 weeks did not result in differences in the amount of tooth movement, anchorage loss, and canine rotation during extraction space closure.

The public perception of the differences between specialist orthodontists and general dentists: A comparison between Australia and Sweden.

INTRODUCTION: In Australia and Sweden, orthodontic treatments may be performed by either a general dental practitioner (GDP) or a specialist orthodontist. Evidence suggests that the public may easily confuse a GDP who provides orthodontic treatment with a specialist orthodontist. We conducted a survey of people in Australia and Sweden to assess their understanding of the differences between a specialist orthodontist and a GDP who provides orthodontic treatments. METHODS: The sample comprised 2006 Australian adults and 1010 Swedish adults who completed an online questionnaire. The survey examined the respondents' understanding of the difference between a GDP and a specialist orthodontist. Demographic data and the respondents' preference concerning future practitioner type were also collected. RESULTS: Although most of the responses between the countries were different with statistical significance (P <0.001), many similarities in the responses were observed. More than 90% of the respondents in both countries did not know the difference between a GDP who provides orthodontic treatment and a specialist orthodontist. Almost 75% believed that a specialist orthodontist was the most qualified practitioner to perform orthodontic treatment. Fewer than 10% of the respondents preferred to see a GDP for orthodontic treatment over a specialist. These people tended to be male, have less education, and be younger. Cost was identified as an important factor in choosing an orthodontic practitioner, particularly in the Australian sample. CONCLUSIONS: The clear majority of both Australian and Swedish respondents were unable to identify the difference between a specialist orthodontic and a GDP who provides orthodontic treatments.

Combined Orthodontic-Surgical Treatment May Be an Effective Choice to Improve Oral Health-Related Quality of Life for Individuals Affected With Severe Dentofacial Deformities.

ARTICLE TITLE AND BIBLIOGRAPHIC INFORMATION: Effect of conventional combined orthodontic-surgical treatment on oral health-related quality of life: A systematic review and meta-analysis. Yi J, Lu W, Xiao J, Li X, Li Y, Zhao Z. Am J Orthod Dentofacial Orthop 2019; 156:29-43. SOURCE OF FUNDING: Government National Natural Science Foundation of China (grant 81801018) and Orthodontic National Key Clinical Specialty Program of China, West China Hospital of Stomatology, Sichuan University. TYPE OF STUDY/DESIGN: Systematic review with meta-analysis.

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.

A comparative histomorphological and micro computed tomography study of the primary stability and the osseointegration of The Sydney Mini Screw; a qualitative pilot animal study in New Zealand rabbits.

OBJECTIVE: The aim of this study was to assess the potential of improving orthodontic miniscrews' (MSs) primary stability in vivo by evaluating the dispersion capacity of an injectable bone graft substitute (iBGS) through a newly designed hollow MS [The Sydney Mini Screw (SMS)] and its integration with the cortical and trabecular bone by using the femur and tibia in a New Zealand rabbit animal model. METHODS: In total, 24 MSs were randomly placed in each proximal tibia and femur of 6 New Zealand rabbits with an open surgery process. Aarhus MSs were used as controls and the effect of injection of iBGS was studied by implanting SMSs with and without iBGS injection. The dispersion of iBGS and the integration of the SMS were studied by using micro Computed Tomography (µCT) and histochemical analysis at two time points, 0 day and 8 weeks post-implantation. RESULTS: iBGS was successfully injected through the SMS and hardened in situ. After 8 weeks, µCT results revealed that the iBGS particles were resorbed and bone tissue was formed around the SMS and within its lateral exit holes. CONCLUSIONS: This pilot animal study showed the high potential of the combined use of iBGS and SMS as a newly developed technique to promote the primary stability of MSs.

Differences in three-dimensional craniofacial anatomy between responders and non-responders to mandibular advancement splint treatment in obstructive sleep apnoea patients.

AIM: The primary aim of this study was to assess the differences in the upper airway morphology between responders and non-responders to mandibular advancement splint (MAS) treatment in obstructive sleep apnoea (OSA) management. The secondary aim was to assess the correlation between the minimum cross-sectional area of the upper airway and the anatomical structures (i.e. mandibular external length, maxillary length, soft palate length, area of the tongue, maxillomandibular enclosure size, and anatomical balance ratio) surrounding the upper airway. The third aim was to assess the differences in the overall skeletal configuration between responders and non-responders to MAS treatment. METHODS: Data from 64 patients (23 females and 41 males) diagnosed with OSA by polysomnography (PSG) at baseline and provided with an adjustable MAS were analysed. All patients had NewTom3G cone beam computed tomography (CBCT) scans, performed in the supine position, at baseline. After acclimatization to MAS, follow-up PSG tests were performed to assess the apnoea-hypopnea index (AHI) with the MAS in situ. Responders were defined by a post-treatment AHI less than 10/hour and at least 50 per cent reduction in AHI, and non-responders by a post-treatment AHI at least 10/hour or less than 50 per cent reduction in AHI. Several upper airway and anatomical variables surrounding the upper airway based on CBCT images were measured to determine the differences between responders and non-responders to MAS. RESULTS: There were 36 responders (AHI = 24.8 ± 11.9 at baseline) and 28 non-responders (AHI = 31.2 ± 20.3 at baseline) to MAS. There were no significant differences in the upper airway morphology between responders and non-responders (P = 0.17-0.93) or in the anatomical structure surrounding the upper airway (P = 0.24-0.58). CONCLUSION: Within the limitations of this study, it can be concluded that there are no significant differences in upper airway morphology and in anatomical structures surrounding the upper airway between responders and non-responders to MAS treatment. These findings suggest that the craniofacial anatomical structures analyzed in this study cannot explain the response to MAS treatment.

Big toenail and hair samples as biomarkers for fluoride exposure - a pilot study.

BACKGROUND: Biomarkers can aid in detecting and preventing clinical disease through the recognition of change in biological samples. The objective of this case-control study was to further the knowledge on the use of big toenail and hair samples as biomarkers for fluoride exposure. METHODS: A total of 48 participants from an endemic (IC) and a non-endemic (SC) fluorosis region were included. Big toenail and hair samples were collected from each participant and the fluoride concentration was determined. The results of 42 participants were reported: 21 participants (11 males and 10 females, mean age 15.66 + 2.61 years) from IC and 21 participants (11 males and 10 females, mean age 15.06 + 0.79 years) from SC. RESULTS: The mean fluoride concentration of big toenail (2.34 ± 0.26 mg/kg) and hair (0.24 ± 0.04 mg/kg) in the endemic region was significantly higher than the mean fluoride concentration of big toenail (0.98 ± 0.08 mg/kg) and hair (0.14 ± 0.02 mg/kg) in the non-endemic region (p < 0.001 and p = 0.004, respectively). The Receiver Operating Characteristic (ROC) analysis showed that the Area Under the Curve (AUC) value was 0.889 for big toenail (p < 0.001) and 0.762 for hair (p = 0.004) samples. The fluoride assay for big toenails exhibits greater observed accuracy than does the fluoride assay for hair. CONCLUSION: Nail and hair samples can serve as biomarkers to detect biological fluoride exposure according to the data of this pilot study. Nevertheless, hair is less sensitive and specific as a biomarker when AUC values of big toenail and hair samples were compared.

Qualitative assessment of awake nasopharyngoscopy for prediction of oral appliance treatment response in obstructive sleep apnoea.

PURPOSE: Clinical methods to identify responders to oral appliance (OA) therapy for obstructive sleep apnoea (OSA) are needed. Awake nasopharyngoscopy during mandibular advancement, with image capture and subsequent processing and analysis, may predict treatment response. A qualitative assessment of awake nasopharyngoscopy would be simpler for clinical practice. We aimed to determine if a qualitative classification system of nasopharyngoscopic observations reflects treatment response. METHODS: OSA patients were recruited for treatment with a customised two-piece OA. A custom scoring sheet was used to record observations of the pharyngeal airway (velopharynx, oropharynx, hypopharynx) during supine nasopharyngoscopy in response to mandibular advancement and performance of the Müller manoeuvre. Qualitative scores for degree (< 25%, 25-50%, 50-75%, > 75%), collapse pattern (concentric, anteroposterior, lateral) and diameter change (uniform, anteroposterior, lateral) were recorded. Treatment outcome was confirmed by polysomnography after a titration period of 14.6 ± 9.8 weeks. Treatment response was defined as (1) Treatment AHI < 5, (2) Treatment AHI < 10 plus > 50% AHI reduction and (3) > 50% AHI reduction. RESULTS: Eighty OSA patients (53.8% male) underwent nasopharyngoscopy. The most common naspharyngoscopic observation with mandibular advancement was a small (< 50%) increase in velopharyngeal lateral diameter (37.5%). The majority of subjects (72.5%) were recorded as having > 75% velopharyngeal collapse on performance of the Müller manoeuvre. Mandibular advancement reduced the observed level of pharyngeal collapse at all three pharyngeal regions (p < 0.001). None of the nasopharyngoscopic qualitative scores differed between responder and non-responder groups. CONCLUSION: Qualitative assessment of awake nasopharyngoscopy appears useful for assessing the effect of mandibular advancement on upper airway collapsibility. However, it is not sensitive enough to predict oral appliance treatment outcome.

Physical properties of root cementum: Part 26. Effects of micro-osteoperforations on orthodontic root resorption: A microcomputed tomography study.

INTRODUCTION: Studies have demonstrated the potential efficacy of micro-osteoperforations in accelerating tooth movement by amplifying the expression of inflammatory markers. The aim of this investigation was to examine the effects of micro-osteoperforations on orthodontic root resorption with microcomputed tomography. METHODS: This prospective controlled clinical trial involved 20 subjects requiring extraction of the maxillary first premolars as part of their orthodontic treatment. A buccal tipping force of 150 g was applied to both premolars. Using the Propel appliance (Propel Orthodontics, San Jose, Calif), micro-osteoperforations were applied at a depth of 5 mm on the mesial and distal aspects in the midroot region of the experimental side of the first premolar root; the contralateral side served as the control. After 28 days, both premolars were extracted. The teeth were scanned under microcomputed tomography, and the volumes of root resorption craters were calculated and compared. RESULTS: Premolars treated with micro-osteoperforation exhibited significantly greater average total amounts of root resorption than did the control teeth (0.576 vs 0.406 mm3). The total average volumetric root loss of premolars treated with micro-osteoperforation was 42% greater than that of the control teeth. CONCLUSIONS: This 28-day trial showed that micro-osteoperforations resulted in greater orthodontic root resorption. However, these results should be verified in patients who are undergoing full-length orthodontic treatment.

Physical properties of root cementum: Part 27. Effect of low-level laser therapy on the repair of orthodontically induced inflammatory root resorption: A double-blind, split-mouth, randomized controlled clinical trial.

INTRODUCTION: The purpose of this 2-arm-parallel split-mouth trial was to investigate the effect of low-level laser therapy (LLLT) on the repair of orthodontically induced inflammatory root resorption (OIIRR). METHODS: Twenty patients were included in this study, with 1 side randomly assigned to receive LLLT, and the other side served as a sham. Eligibility criteria included need for bilateral maxillary first premolar extractions as part of fixed appliance treatment. OIIRR was generated by applying 150 g of buccal tipping force on the maxillary first premolars for 4 weeks. After the active force was removed, the teeth were retained for 6 weeks. LLLT commenced with weekly laser applications using a continuous beam 660-nm, 75-mW aluminum-gallium-indium-phosphorus laser with 1/e2 spot size of 0.260 cm2, power density of 0.245 W/cm2, and fluence of 3.6 J/cm2. Contact application was used at 8 points buccally and palatally above the mucosa over each tooth root for 15 seconds with a total treatment time of 2 minutes. After 6 weeks, the maxillary first premolars were extracted and scanned with microcomputed tomography for primary outcome OIIRR calculations. Subgroup analysis included assessment per root surface, per vertical third, and sites of heaviest compressive forces (buccal-cervical and palato-apical). Randomization was generated using www.randomization.com, and allocation was concealed in sequentially numbered, opaque, sealed envelopes. Blinding was used for treatment and outcome assessments. Two-tailed paired t tests were used to determine whether there were any statistically significant differences in total crater volumes of the laser vs the sham treated teeth. RESULTS: Total crater volumes were 0.746 mm3 for the laser treated teeth and 0.779 mm3 for the sham. There was a mean difference of 0.033 ± 0.39 mm3 (95% CI, -0.21 to 0.148 mm3) greater resorption crater volume in the sham group compared with the laser group; this was not statistically significant (P = 0.705). No harm was observed. CONCLUSIONS: No significant difference was found between LLLT and sham control groups in OIIRR repair.