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Introduction For patients with complete unilateral cleft lip and palate (CUCLP), secondary alveolar bone grafting (SABG) can be performed before or after the emergence of the cleft side permanent canine (pre-CE and post-CE, respectively). The controversy regarding dental outcomes related to the timing of SABG remains unsettled. The objective of this study was to evaluate dental survival and specific dental outcomes of cleft-adjacent teeth in children with CUCLP who received either pre-CE or post-CE SABG. Methods The permanent maxillary canines and the central and lateral incisors of 21 pre-CE and 23 post-CE SABG subjects with nonsyndromic CUCLP and all cleft-related surgeries performed by the same surgeon were analyzed retrospectively. Intraoral radiographs and clinical chart notes were collected at age 7 years, at the time of the SABG, and approximately 4 years after the grafting. Dental survival, spontaneous canine eruption, planned prosthetic replacement, root development, and root resorption were analyzed. Results Dental outcomes on the noncleft side were better than those on the cleft side. On the cleft side, dental survival of the cleft-adjacent teeth was not significantly different between the pre-CE and post-CE SABG groups (P >0.05). Most teeth completed root development after grafting, and the cleft side canine root development in the pre-CE SABG group appeared to accelerate after SABG. Trends showed that the pre-CE SABG group suffered less root resorption (16.28%; post-CE: 22.73%; P >0.05) and received fewer planned prosthetic replacements (14.29%; post-CE: 26.01%; P >0.05) but required a greater number of canine exposures (33.33%; post-CE: 4.55%; P = 0.02). Conclusions Pre-CE SABG showed better dental outcomes in patients with CUCLP, with fewer adverse dental outcomes than post-CE SABG.

Objective The aim of this study was to evaluate dentoskeletal changes in the treatment of Class II malocclusion with the Herbst Cantilever Bite Jumper (CBJ) appliance, associated with multibracket appliances after the growth peak, at pretreatment. Materials and Methods A sample of 37 individuals was divided into two groups: the experimental group comprised 16 patients treated consecutively for a mean period of 2.52 years with the Herbst CBJ appliance associated with multibracket appliances. A total of 21 subjects (10 males and 11 females) with Class II malocclusion and mean age at T1 of 16.08 years were followed for a mean period of 2.12 years composed the control group. Comparisons between the two groups were performed using initial and final lateral cephalograms. Comparisons between experimental and control groups at pretreatment and of the treatment changes were performed by Mann–Whitney or independent t-tests. Results Experimental group exhibited a significantly greater labial inclination of the mandibular incisors in comparison to the control group. Additionally, significantly greater corrections in overbite, overjet, and molar relationship were observed in the experimental than in the control groups. Conclusion The effects of the Herbst CBJ appliance, associated with fixed appliances after the growth peak in Class II malocclusion treatment are correction in molar relationship toward a Class I relationship, decrease of the overjet, decrease of the overbite, and mandibular incisors labial inclination.

The aim of this study was to evaluate the possible effect of low intensity pulsed ultrasound (LIPUS) on tooth movement and root resorption in orthodontic patients. Twenty-one patients were included in a split-mouth study design (group 1). Ten additional patients were included with no LIPUS device being used and this group was used as the negative control group (group 2). Group 1 patients were given LIPUS devices that were randomly assigned to right or left side on upper or lower arches. LIPUS was applied to the assigned side that was obtained by randomization, using transducers that produce ultrasound with a pulse frequency of 1.5 MHz, a pulse repetition rate of 1 kHz, and average output intensity of 30 mW/cm2. Cone-beam computed tomography (CBCT) images were taken before and after treatment. The extraction space dimensions were measured every four weeks and root lengths of canines were measured before and after treatment. The data were analyzed using paired t-test. The study outcome showed that the mean rate of tooth movement in LIPUS side was 0.266 &plusmn, 0.092 mm/week and on the control side was 0.232 &plusmn, 0.085 mm/week and the difference was statistically significant. LIPUS increased the rate of tooth movement by an average of 29%. For orthodontic root resorption, the LIPUS side (0.0092 &plusmn, 0.022 mm/week) showed a statistically significant decrease as compared to control side (0.0223 &plusmn, 0.022 mm/week). The LIPUS application accelerated tooth movement and minimized orthodontically induced tooth root resorption at the same time.

Objectives: To describe qualitatively and quantitatively the directions and magnitudes of rotations of permanent maxillary central incisors and first molars in the mixed dentition in repaired complete unilateral cleft lip and palate (UCLP) and study their associations with absence of teeth in their vicinity. Materials and Methods: Dental casts and orthodontic records taken prior to orthodontic preparation for alveolar bone grafting of 74 children with repaired UCLP (53 male, 21 female; aged 8.9 ± 1.0 years) were studied. Directions and magnitudes of permanent maxillary central incisor and first molar rotations were recorded. Tooth absence was confirmed from longitudinal radiographic records. Incisor and molar rotations were analyzed in relation to the absence of teeth in their vicinity. Results: Distolabial rotation of the permanent maxillary central incisor was noted in 77.14% on the cleft side, while distopalatal rotation was noted in 82.19% on the noncleft side. Incisor rotation was greater when a permanent tooth was present distal to the cleft side central incisor, in the greater segment. The permanent maxillary first molar showed mesiopalatal rotation, which was greater on the cleft side and when there was absence of one or more teeth in the buccal segment. Conclusions: Presence and absence of teeth were associated with the severity of incisor and molar rotations in UCLP. Crowding of anterior teeth in the greater segment was associated with a greater magnitude of rotation of the cleft side permanent central incisor. Absence of one or more buccal segment teeth was associated with greater magnitude of rotation of the molar.

Introduction The influence of 4 commonly used fixed orthodontic appliances on artifact formation and diagnostic quality of magnetic resonance (MR) images of the head produced by a 3-T MR scanner was studied. Methods Stainless steel brackets, ceramic brackets, combination of ceramic brackets and steel molar tubes, and multistranded steel mandibular lingual retainers were embedded into custom-made trays for each of 10 adult subjects. Head MR scans of 9 regions were acquired for each subject wearing these trays. Sagittal T1-weighted, axial T2-weighted, axial gradient-recalled, axial diffusion-weighted, noncontrast axial MR angiography, and axial fluid-attenuated inversion recovery MR sequences were included. Two neuroradiologists evaluated image distortions and diagnostic qualities of the 1314 acquired images (13860 image slices). Results The images were affected by appliance, head region, and MR sequence. Stainless steel brackets and molar tubes affected the images the most, and ceramic brackets caused minimal image distortion. Conclusions Head MR images are differentially affected by orthodontic appliances. The appliance, region imaged, and MR sequence should be considered before imaging patients wearing fixed orthodontic appliances.

Objective: To compare the mixed dentition incisor and molar overjet, severity of contraction of the dental arch, and the sagittal molar relationship on the cleft side vs the noncleft side in children with repaired complete unilateral cleft of the lip and palate (UCLP). Materials and Methods: Orthodontic records taken prior to orthodontic preparation for alveolar bone grafting were screened to select study casts from patients with nonsyndromic repaired complete UCLP who did not have mandibular skeletal or dental asymmetry. The study sample comprised dental casts from 74 children aged 8.9 ± 1 years. Standardized digital photographs were acquired at 1:1 magnification. A coordinate system was developed using digital image-processing software (Photoshop CS4 and Adobe Illustrator). Incisor and molar overjet, Angle's classification, and arch contraction were recorded. Descriptive statistics, paired t-tests, and kappa statistics were used to compare the cleft and noncleft sides. Results: A negative overjet of −1 to −5 mm was often present at the incisors, with greater frequency and magnitude on the cleft side. Class II molar relation was more frequent on the cleft side (61.1%) than on the noncleft side (47.2%). Significantly greater contraction of the cleft side deciduous canine and deciduous first molar was noted, while the difference was very minor at the first permanent molar. Conclusions: Cleft side maxillary arch contraction was most severe in the deciduous canine and first deciduous molar region and progressively less severe in the posterior region of the arch. A greater frequency and severity of negative overjet and Class II molar relationship was seen on the cleft side.

Objective Maxillary growth in patients with cleft lip and palate is highly variable. The authors' aim was to investigate associations between preoperative cleft lip measurements and maxillary growth determined cephalometrically in patients with complete unilateral cleft lip and palate (cUCLP). Design Retrospective cross-sectional study. Patients Children with cUCLP. Methods Preoperative cleft lip measurements were made at the time of primary cheiloplasty and available for each patient. Maxillary growth was evaluated on lateral cephalometric radiographs taken prior to any orthodontic treatment and alveolar bone grafting (8.5 ± 0.7 years). The presence of associations between preoperative cleft lip measurements and cephalometric measures of maxillary growth was determined using regression analyses. Results In the 58 patients included in the study, the cleft lateral lip element was deficient in height in 90% and in transverse width in 81% of patients. There was an inverse correlation between cleft lateral lip height and transverse width with a β coefficient of −0.382 ( P = .003). Patients with a more deficient cleft lateral lip height displayed a shorter maxillary length (β coefficient = 0.336; P = .010), a less protruded maxilla (β coefficient = .334; P =.008), and a shorter anterior maxillary height (β coefficient = 0.306; P = .020) than those with a less deficient cleft lateral lip height. Conclusions Patients with cUCLP present with varying degrees of lateral lip hypoplasia. Preoperative measures of lateral lip deficiency are related to later observed deficiencies of maxillary length, protrusion, and height.

Purpose The purpose of this study was to evaluate the maxillary incisors position and soft-tissue characteristics of Class II, division 1 patients treated with non-extraction, 2-maxillary and 4-premolar extraction protocols. Materials and methods The sample of 120 subjects was divided into four groups. The first three treated groups presented Class II, division 1 malocclusion patients. G1 comprised 30 patients (14.95 years), and was treated without extraction. G2 comprised 30 patients (15.28 years), treated with extraction of 2-maxillary premolars. G3 consisted of 30 patients (15.55 years), treated with extraction of 4-premolars, and G4 included 30 individuals (14.93 years) with normal occlusion. The occlusal features of the treated groups were evaluated by the Peer Assessment Rating (PAR) index and the cephalometric characteristics were compared with ANOVA. Results The maxillary incisors were similarly positioned among the treated groups at the end of treatment. However, they were more upright in G2 and G3 than in the control group (G4). The hard- and soft-tissue cephalometric characteristics were similar in all groups. Conclusion Class II treatment conducted non-extraction, with 2-maxillary and with 4-premolar extraction protocols showed similar effects on final maxillary incisors positioning and nasolabial angle. In general, the 4-premolar extraction protocol was potentially more retrusive, but the dentofacial differences were slight and not statistically significant.

Objective To investigate the stability of major versus minor Le Fort I maxillary advancements in unilateral cleft lip and palate (UCLP) patients. Design A retrospective longitudinal study was undertaken on 30 nonsyndromic UCLP patients treated with the same protocol at The Hospital for Sick Children, Toronto, Canada. Patients were grouped into major and minor movement groups based on planned surgical advancement. Standard lateral cephalometric radiographs were taken preoperatively (T1), immediately postoperatively (T2), and at least 1 year postoperatively (T3). Skeletal and dental variables were measured using cephalometric analysis. Stability was compared between groups using repeated-measures analysis of variance. Linear regression analysis was used to assess the relationship between advancement and relapse for the entire study population. Results A mean maxillary advancement of 9.8 mm and 4.9 mm was seen for the major (n = 10) and minor (n = 20) movement groups, respectively. The mean skeletal horizontal relapse was 1.8 mm (18%) for the major advancement group and 1.5 mm (31%) for the minor advancement group. There was no significant difference in skeletal horizontal relapse between the groups ( P > .05). The correlation coefficient ( r) between linear horizontal advancement and relapse was calculated to be .31 ( P > .05). Dental horizontal relapse was not significant for either the major or minor groups, and no significant difference was found between the groups ( P > .05) Conclusion Skeletal and dental relapse was found to be unrelated to the amount of maxillary linear advancement using conventional Le Fort I osteotomies in UCLP.

Purpose To investigate the stability of single-piece versus segmental (2-piece) maxillary advancement in patients with unilateral cleft lip and palate (UCLP) treated using conventional Le Fort I orthognathic surgery. Patients and Methods A retrospective study was undertaken in 30 patients with nonsyndromic UCLP treated with the same surgical and orthodontic protocol from 2002 through 2011. Standard lateral cephalometric radiographs were taken preoperatively, immediately postoperatively, and at least 1 year postoperatively. Patients were divided into single-piece and segmental Le Fort I groups based on planned surgical movement. Postoperative movements were compared between groups using repeated measures analysis of variance. Results The mean skeletal horizontal advancement was 7.3 and 7.5 mm in the single-piece and segmental groups, respectively. The skeletal horizontal relapse was 1.3 mm (18%) for the single-piece group and 1.9 mm (25%) for the segmental group. The skeletal surgical extrusion was 2.7 mm for the 2 groups. The skeletal vertical relapse was 0.6 mm (22%) and 1.5 mm (56%) for the single-piece and segmental groups, respectively. The mean dental horizontal postoperative movement was an advancement of 0.4 mm for the single-piece group and a relapse of 0.2 mm (3%) for the segmental group. The mean dental vertical relapse was 0.1 mm (4%) for the single-piece group and 0.3 mm (11%) for the segmental group. There was no statistically significant difference in relapse between the single-piece and segmental groups for all movements ( P > .05). Conclusion Skeletal and dental relapse was similar between single-piece and segmental maxillary advancements using conventional Le Fort I orthognathic surgery in patients with UCLP.

Introduction Coinciding treatment with periods of accelerated skeletal growth and maturation might be advantageous in clinical practice. Better understanding of the concordance between skeletal and chronologic ages during the period that children frequently receive orthodontic treatment is needed. The literature on skeletal age determination from hand-wrist radiographs lacks reports based on longitudinal data, creating lacunae in the understanding of the magnitudes and variations of differences between skeletal and chronologic ages. The aims of this research were to comprehensively analyze the concordance between skeletal and chronologic ages determined by using the Greulich and Pyle method at different ages in the preadolescent and adolescent periods, and to determine any age- and sex-related differences in the concordance. Methods By using the Greulich and Pyle method, skeletal age determinations were made from 572 hand-wrist radiographs of 68 white children with normal facial growth, selected from the records of the Burlington Growth Centre, spanning the growth period from 9 to 18 years. Skeletal age and chronologic age differences for each sex were analyzed by using paired t tests and Wilcoxon signed rank tests at yearly intervals. Differences over the longitudinal duration were examined by using the mixed model approach. The limits of agreement were determined by using the Bland-Altman method. In each yearly chronologic age group, differences were clinically categorized based on the proximity of the skeletal and chronologic ages. Results Overall, a slightly greater proportion of the total skeletal age determinations made in girls (41.9%) were within 0.5 year of their chronologic age, compared with 38% in boys. The largest proportions of subjects having skeletal age-chronologic age differences within 0.5 year were in the 10-year age group in girls (64.5%) and the 13-year age group in boys (64.7%). Mean skeletal age-chronologic age differences were significantly larger in the 13- to 16-year age groups in girls and in the 16- and 17-year age groups in boys, but the differences were not statistically significant at other ages. Several patterns of variations were identified in the direction of differences when individual plots were examined. Conclusions This longitudinal analysis of differences between skeletal and chronologic ages showed wide ranges and distributions of differences at each yearly age group during the growth period from 9 to 18 years, even when mean differences were small. Variations in the magnitude and direction of differences observed at different ages highlighted the variability in skeletal maturation among normally growing young people. Overall, the differences in skeletal and chronologic ages were positively related to age, with little effect of sex or its interaction with age.

Objective: To compare posttreatment and postretention occlusal changes with the physiologic occlusal changes caused by natural development of untreated subjects. Materials and Methods: The sample was divided into three groups. Group 1 comprised 97 subjects treated with four premolar extractions at a mean pretreatment (T0) age of 13.03 years, a mean posttreatment (T1, first observation) age of 15.12 years, and a mean postretention (T2, second observation) age of 20.52 years. The mean observation period (T2-T1) was 5.39 years. Group 2 comprised 58 subjects treated nonextraction at a mean pretreatment age of 12.83 years, a mean posttreatment age of 14.99 years, a mean postretention age of 20.22 years, and a mean observation period of 5.22 years. Group 3 comprised 114 untreated subjects at a mean age at T1 of 14.91 years and at T2 of 20.48 years. The mean observation period was 5.56 years. Dental casts were evaluated using the Peer Assessment Rating (PAR) index and the Little irregularity index in maxillary and mandibular arches. Changes in PAR and Little indexes were compared among the three groups by analysis of variance and Tukey tests. Results: Intergroup comparison showed that at T1 and T2 the treated groups presented smaller PAR and Little indexes than the untreated group. In the observation period, the treated groups showed greater increase in PAR and Little maxillary indexes than the untreated group. The extraction group showed a greater increase of the Little mandibular index than the untreated group. Conclusions: The treated groups showed more changes according to PAR and Little maxillary indexes than the untreated group. The posttreatment change of the mandibular anterior crowding of the treated extraction group was greater than the mandibular crowding caused by physiologic changes in the untreated group.

Objective: To elucidate some of the parameters determining the frictional behavior of passive, active, and interactive self-ligating brackets during sliding mechanics. Materials and Methods: A custom jig mimicking the three-dimensional tooth movements that occur during sliding mechanics and an Instron testing machine were used to determine the resistance to sliding of six different self-ligating brackets (SPEED, In-Ovation C, CarriereSLB, ClaritySL, SmartClip, VisionLP). Each bracket was tested on three rectangular stainless steel wires: 0.017 3 0.022 inch, 0.017 3 0.025 inch, and 0.019 3 0.025 inch. A two-way balanced analysis of variance was used for statistical analysis. Results: The four passive self-ligating brackets (CarriereSLB, ClaritySL, SmartClip, VisionLP) displayed significantly lower frictional resistance (P , .001) than the remaining brackets, which featured an active (SPEED) or interactive (In-Ovation C) clip. The SPEED bracket consistently demonstrated the highest resistance to sliding. Conclusions: The mode of self-ligation appears to be the primary variable in determining the frictional behavior of orthodontic brackets undergoing sliding mechanics. Passive self-ligating brackets demonstrated significantly lower frictional resistance to sliding. With regard to the resistance of active self-ligating brackets, the depth (buccolingual thickness) of the wire had a more significant influence than its height. (Angle Orthod. 2011;81:1036-1044.)

The cervical vertebrae have been proposed as a method of determining biologic maturity. The purposes of this study were to establish a pattern of mandibular growth and to relate this pattern to the stages of cervical vertebral maturation.Cephalometric radiographs, taken annually from ages 9 to 18 years, were evaluated for 90 boys from the Burlington Growth Center, Toronto, Ontario, Canada. Mandibular lengths were measured from articulare to gnathion, and incremental growth was determined. Cervical vertebral maturation stages were assessed by using a 6-stage method. Advanced, average, and delayed maturation groups were established.The prepubertal mandibular growth minimum velocity occurred during cervical stages 1 through 4 (P = 0.7327). Peak mandibular growth velocity occurred most frequently during stage 4 in all 3 maturation groups, with a statistical difference in the average and delayed groups (P0.0001) and the advanced group (P = 0.0143). The average number of years spent in stage 4 was 3.79 (P0.0001). The average amount of mandibular growth occurring during stage 4 was 9.40 mm (P0.0001). The average amount of growth in stages 5 and 6 combined was 7.09 mm.Progression from cervical stages 1 through 6 does not occur annually; time spent in each stage varies depending on the stage and the maturation group. Cervical vertebral maturation stages cannot accurately identify the mandibular prepubertal growth minimum and therefore cannot predict the onset of the peak in mandibular growth. The cervical vertebral maturation stages should be used with other methods of biologic maturity assessment when considering both dentofacial orthopedic treatment and orthognathic surgery.

Although the associations between oral biologic variables such as malocclusion and oral-health-related quality of life (OHRQOL) have been explored, little research has been done to address the influence of psychological characteristics on perceived OHRQOL. The aim of this study was to assess OHRQOL outcomes in orthodontics while controlling for individual psychological characteristics. We postulated that children with better psychological well-being (PWB) would experience fewer negative OHRQOL impacts, regardless of their orthodontic treatment status.One hundred eighteen children (74 treatment and 44 on the waiting list), aged 11 to 14 years, seeking treatment at the orthodontic clinics at the University of Toronto, participated in this study. The child perception questionnaire (CPQ11-14) and the PWB subscale of the child health questionnaire were administered at baseline and follow-up. Occlusal changes were assessed by using the dental aesthetic index. A waiting-list comparison group was used to account for age-related effects.Although the treatment subjects had significantly better OHRQOL scores at follow-up, the results were significantly modified by each subject's PWB status (P 0.01). Furthermore, multivariate analysis showed that PWB contributed significantly to the variance in CPQ11-14 scores (26%). In contrast, the amount of variance explained by the treatment status alone was relatively small (9%).The results of this study support the postulated mediator role of PWB when evaluating OHRQOL outcomes in children undergoing orthodontic treatment. Children with better PWB are, in general, more likely to report better OHRQOL regardless of their orthodontic treatment status. On the other hand, children with low PWB, who did not receive orthodontic treatment, experienced worse OHRQOL compared with those who received treatment. This suggests that children with low PWB can benefit from orthodontic treatment. Nonetheless, further work, with larger samples and longer follow-ups, is needed to confirm this finding and to improve our understanding of how other psychological factors relate to patients' OHRQOL.

Objective To evaluate nasal morphology, symmetry, and nostril shape in patients with unilateral cleft lip and palate following mixed-dentition alveolar bone grafting. Design Prospective stereophotogrammetric study. Setting Hospital-based. Patients Thirty-nine patients with a history of repaired unilateral cleft lip and palate who received an iliac crest alveolar bone graft were recruited prospectively to participate in the study. Each patient served as his/her own control. Interventions Partial facial impressions of all patients were acquired before and a minimum of 6 months after the alveolar bone grafting procedure. Image acquisition and analysis of the casts constructed from these models were carried out using three-dimensional stereophotogrammetry. Main Outcome Measures Surface-based registrations and linear measurements were performed to assess nasal morphology and nostril shape. A modified Procrustes technique was used to determine the change in nasal symmetry. A two-tailed, paired t test and an analysis of covariance were used to assess statistical significance. Results Significant side-to-side asymmetry exists in the nasal region of patients with unilateral cleft lip and palate, both before and after alveolar bone grafting. No significant changes were observed between pre–alveolar bone graft and post–alveolar bone graft images based on linear measurements, asymmetry scores, and registrations. Gender and surgeon were not significant factors. Conclusion Under the conditions of this study, mixed-dentition alveolar bone grafting appears to have no significant long-term effect on nasal morphology, symmetry, or nostril shape.

Introduction Studies of computer-aided learning (CAL) in orthodontics have documented both objective and subjective outcomes; however, to date, no studies have attempted to correlate these 2 outcome measures. Methods The main objective outcome measured was performance on a written test covering material in the orthodontic diagnosis electronic tutorial (ODET) administered to 92 fourth-year undergraduate dental students. The main subjective outcome measured was a 12-statement questionnaire to elicit students' perception of the ODET and CAL as teaching modalities. Results In the male and female subgroups, a statistically significant difference in mean lecture test scores favoring women (72.46%) over men (67.08%) was observed ( P = 0.05). This difference was not observed for mean ODET test scores ( P = 0.52). Although responses to the questionnaire were mostly positive, the students are not prepared to replace lectures with CAL tutorials. Responses showed that male students preferred self-instruction as a mode of learning more than female students did ( P = 0.05). When linking objective and subjective outcomes, the mean ODET test score had a statistically significant ( P = 0.025), but weak, positive correlation (r = 0.243) with self-reported time spent reviewing the ODET but not with any other statement in the questionnaire. Conclusions Despite a difference in lecture test scores between male and female students, there was no difference in mean ODET test scores between the 2 subgroups. This might be explained by sex differences: male students preferred self-instruction more than female students did. Improved performance on the ODET test was noted for students who reported longer times spent reviewing the tutorial. Because students are not prepared to replace lectures with CAL tutorials, from their perspective, the ODET should continue to be used with traditional modes of learning.

Objectives. To assess the functional and psychosocial impact of oligodontia in children aged 11–14 years. Methods. Children aged 11–14 years with oligodontia were recruited from orthodontic clinics when they presented for orthodontic evaluation. All completed a copy of the Child Perceptions Questionnaire for 11- to 14-year olds, a measure of the functional and psychosocial impact of oral disorders. Information on the number and pattern of missing teeth for each child were obtained from charts and radiographs. Results. Thirty-six children were included in the study. The number of missing teeth ranged from one to 14 (mean = 6.8). Just over three-quarters of the subjects reported experiencing one or more functional and psychosocial impacts ‘Often’ or ‘Everyday/almost everyday’. Correlations between scale and sub-scale scores and the number of missing teeth were weak and nonsignificant. Conclusions. Children with oligodontia experience substantial functional and psychosocial impacts from the condition. When compared with other clinical groups, children with oligodontia appear to have worse oral health-related quality of life than children with dental decay and malocclusion, but better oral health-related quality of life than children with oro-facial conditions.

M-Wire (Sportswire LLC, Langley, OK) is reportedly created by altering alloy temperatures during the manufacturing process of GT series X instruments (Dentsply Tulsa Dental Specialties, Tulsa, OK). Currently, there are few published studies looking at torsional profiles of these instruments. The purpose of this study was to investigate the torsional profiles of new and used 20/0.06 GT series X (GTX) and GT (GT) instruments (Dentsply Tulsa Dental Specialties).Thirty instruments were allocated to one of eight groups and were used 2, 6, or 10 times in simulated canals or remained as unused controls. Testing of torque (TF) and angle at fracture (AF) were conducted in accordance with American National Standards Institute/American Dental Association (ANSI/ADA) specification No. 28. Data analyses were performed by using one- and two- way analysis of variance with honesty significance difference post hoc comparison with alpha = 0.05.Overall, there were significant differences in TF and AF among the experimental groups (p0.001). GTX instruments showed a significant initial increase in TF with two and six uses (p0.001) in contrast to the GT, which showed a linear reduction in TF with increased use (p0.004). Both GTX and GT instruments showed no statistical difference in AF of new instruments but did show a significant decrease in AF in all groups except the GT two-use group (p0.02).The GTX instruments had a higher resistance to torsional failure after use as compared with the GT.

Introduction Many young patients are asked to wear headgear or functional appliances during sleep as part of their orthodontic treatment. The objective of this clinical study was to assess the impact of these appliances on sleep quality. Methods Twenty-two subjects (8 boys, 14 girls) between 10 and 15 years of age wearing either a headgear or a removable appliance for 3 to 12 months were enrolled in a sleep study. Each subject participated in 2 overnight sleep studies with and without the appliance. There was a 1-week interval after an adaptation night. The studies were performed at the Sleep Research Laboratory at Toronto Western Hospital in Canada. Each subject served as his or her own control. Twelve subjects had an extraoral headgear appliance, and 10 had intraoral functional (5 Frankel, 5 Twin-block) appliances. No subject reported any sleep or medical disorder. The primary outcome variable was sleep efficiency. Results Sleep efficiencies were 90.7% (SD, 7.9) and 91.6% (SD, 4.3) with and without the appliances, respectively. When sleep quality was compared with and without appliances, analysis of variance (ANOVA) showed no significant difference in sleep efficiency or other sleep variables such as sleep onset latency, rapid eye movement onset latency, rapid eye movement percentage, short-wave sleep percentage, or respiratory disturbance index. Sex and body mass index were not confounding variables. In addition, the use of extraoral or intraoral appliances did not affect sleep quality. Conclusions In young orthodontic patients, there appears to be no difference in sleep quality with or without the overnight use of these appliances after they have been worn for a minimum of 3 months.

SUMMARY The objective of this investigation was to assess and compare the in vitro tribological behaviour of four commercially available self-ligating bracket systems. The frictional characteristics of the Damon3 ™ , Speed ™ , In-Ovation R ™ , and Time2 ™ bracket systems were studied using a jig that mimics the three-dimensional movements that occur during sliding mechanics. Each bracket system was tested on the following stainless steel archwires: 0.016 × 0.022, 0.019 × 0.025, 0.020 round , and 0.021 × 0.021 inch Speed ™ D-wire. An Instron testing machine with a 50 N load cell was used to measure the frictional resistance for each bracket/tooth assembly. The crosshead speed was set at a constant rate of 1 mm/minute, and each typodont tooth was moved along a fi xed wire segment for a distance of 8 mm. Descriptive statistical analysis for each bracket/archwire combination with regard to frictional resistance was performed with a two-way, balanced analysis of variance for bracket type and wire size. The Damon3 ™ bracket consistently demonstrated the lowest frictional resistance to sliding, while the Speed ™ bracket produced signifi cantly ( P < 0.001) more frictional resistance than the other brackets tested for any given archwire. The self-ligation design (passive versus active) appears to be the primary variable responsible for the frictional resistance generated by self-ligating brackets during translation. Passively ligated brackets produce less frictional resistance; however, this decreased friction may result in decreased control compared with actively ligated systems.

Introduction: The purpose of this study was to examine the relationship between self-esteem and oral-health-related quality of life (OHRQoL) in a sample of children seeking orthodontic treatment in Toronto, Ontario, Canada. Methods: This was a cross-sectional study of children aged 11 to 14 years, evaluating the associations among the child perception questionnaire (CPQ11-14), the self-esteem subscale of the child health questionnaire, and the dental aesthetic index (DAI). Results: The CPQ11-14 scores were significantly related to the self-esteem scores and the DAI ratings. Regression analysis showed that self-esteem contributed significantly to the variance in CPQ11-14 scores. However, the amount of variance explained by normative measures of malocclusion was relatively small. Conclusions: The impact of malocclusion on quality of life is substantial in children with low self-esteem. Compared with normative measures of malocclusion, self-esteem is a more salient determinant of OHRQoL in children seeking orthodontic treatment. Longitudinal data will be of value to confirm this finding.

Advances in skeletal stabilization techniques have led to the use of titanium devices for rigid fixation. Their advantages include strength and skeletal stability, but they also have disadvantages. The purpose of this study was to investigate the stability of a resorbable copolymer as a potential alternative to titanium for fixation of Le Fort I maxillary impaction.Fifty consecutive patients underwent maxillary impaction with nonsegmental monopiece Le Fort I osteotomy. Twenty-five patients were treated with titanium fixation; 25 patients were treated with resorbable copolymer fixation (82% poly-L-lactic acid: 18% polyglycolic acid). Lateral cephalograms were obtained 1 week preoperatively, 1 week postoperatively, and a minimum of 8 months postoperatively. Linear and angular measurements were recorded digitally to evaluate 2-dimensional skeletal changes.Statistical analysis showed no significant radiographic differences (P0.05) in long-term stability in or between the 2 groups. No clinical or radiographic evidence of wound healing problems was noted.These results support the use of resorbable copolymer fixation for Le Fort I impaction as a viable alternative to titanium fixation.

Introduction: In this prospective clinical study, we used bilateral temporomandibular joint (TMJ) magnetic resonance images (MRIs) to investigate the condylar response to rapid maxillary expansion (RME). Methods: Bilaterial MRIs of the TMJs of 18 subjects (11 girls, 7 boys; mean age, 12.54 years; range, 9.75-14.8 years) were assessed. All subjects had unilateral or bilateral posterior crossbites involving 3 or more posterior teeth. There was no control group because of the short observation period. The MRI protocol included closed-mouth parasagittal proton density weighted spin echo and fat-suppressed short T1 inversion recovery sequences. The MRIs were taken before treatment (Tx 1), and at 6 weeks (Tx 2) and at 18 weeks (Tx 3) after treatment. Alterations in the signal intensities of the TMJ region were examined visually by a radiologist who was blinded to the subjects' characteristics. Results: Increased signal intensities appeared as bright areas on the MRIs, indicating red bone marrow edema that is a sign of condylar remodeling. There were no bright areas in the condylar regions at Tx 2 in the 36 TMJs. Bright areas at the condylar region were observed both in proton density and fat-suppressed spin echo sequences at Tx 3 in 32 TMJs. Twenty-two TMJs had bright areas localized at the condylar head, and 10 TMJs had bright areas that extended through both the condyle and the mandibular ramus. No bright areas were seen at Tx 2 or Tx 3 for 4 TMJs. Conclusions: A condylar response to RME was observed in 32 TMJs at 18 weeks after expansion. Both the extensive orthopedic and the functional occlusal forces associated with RME have roles in condylar and ramal responses.

Introduction: The aim of this prospective study was to assess temporomandibular joint (TMJ) condyle-disc positions at the sagittal and coronal planes of magnetic resonance images (MRIs) before and after rapid maxillary expansion (RME). Methods: The study included 18 subjects (11 girls, 7 boys) with a mean age of 12.54 years with unilateral or bilateral posterior crossbite that included at least 3 posterior teeth. The clinical and radiographic assessments of the TMJ were done before (T1) and 18 weeks after (T2) RME. A Haas-type expansion appliance was used for an average treatment time of 3.5 weeks. Results: A visual MRI analysis of pretreatment condyle-disc positions showed that 8 TMJs had medial disc displacement, 3 had anteromedial disc displacement, and 2 had lateral disc displacement. The disc positions remained unchanged at T2 except in 1 subject, who developed unilateral anterior disc displacement. Unilateral joint sounds developed in 3 subjects without changes in the disc positions. Conclusions: Posterior crossbite can be considered a minor risk factor for temporomandibular disorder (TMD). RME is neither a risk factor nor a prevention for TMD. Coronal MRIs contribute complementary information for optimal diagnosis of TMD.

Increasing the rate of orthodontic tooth movement (OTM) can reduce risks such as periodontal disease and caries.This split-mouth randomized controlled clinical trial investigated whether light emitting diode (LED) phototherapy could accelerate the rate of OTM.The study was conducted at the Graduate Orthodontics Clinic at the University of Toronto, Faculty of Dentistry.17 dental arches from 11 orthodontic participants with bilaterally symmetrical extraction of premolars were included. During space closure of single tooth extraction sites, LED phototherapy was applied to one side of the dental arch for a specified time and the contralateral side acted as the control. Space closure was measured immediately prior to, during and later in space closure.All participants were compliant with LED application. Our results revealed no significant changes in the rate of OTM with LED phototherapy over 3 months of extraction space closure.Our findings were contrary to previous findings of the effect of laser phototherapy on regulating the rate of OTM. Further investigations are warranted to analyse whether the duration or method of LED delivery would have an effect on the rate of OTM. Toronto. This trial was registered at clinicaltrials.gov (NCT01490385).

Background: Mandible advancement osteotomy in juvenile rheumatoid arthritis patients for class II anterior open-bite malocclusion is controversial; however, there is no literature discussing outcomes of surgery in this group of patients. An evaluation of such outcomes was undertaken at The Hospital for Sick Children. Methods: A retrospective chart review revealed that eight patients with juvenile arthritis underwent orthognathic surgery during a period of 5 years. All of the patients had a bilateral sagittal split osteotomy of the mandible, six had a simultaneous Le Fort I osteotomy, and four had an additional advancement genioplasty. The age of the patients at the time of surgery ranged between 17 and 22 years (mean, 18 years), with three male patients and five female patients. The patients were under follow-up for a minimum of 8 months after surgery, and measurements were performed studying preoperative and postoperative lateral cephalometric radiographs. Results: All patients have an improved occlusion and improved facial aesthetics. One patient continued to suffer from temporomandibular joint pain. The mean mandible advancement was 9.6 mm (range, 3.9 to 18.3 mm). The mean mandible relapse after surgery was 2.1 mm (range, 1 to 3.1 mm). No exacerbation of the juvenile rheumatoid arthritis was encountered as a result of the surgical procedure. Conclusions: Orthognathic surgery in juvenile rheumatoid arthritis patients improves the patient’s occlusion, facial aesthetics, and therefore quality of life. The relapse rate postoperatively did not significantly affect the clinical outcome, and the authors recommend orthognathic surgery for this patient population. Future presurgical plans in this patient population will include a small posterior open bite and positioning the incisors edge to edge to allow for some postoperative relapse.

Background: Mandible reconstruction in the growing facial skeleton is challenging, especially with reconstructions necessitating free vascularized bone grafts. The need for further combined orthodontic-orthognathic intervention at skeletal maturity must be anticipated. The growth potential of these grafts and potential new problems associated with performing a sagittal split osteotomy at skeletal maturity are poorly understood. Methods: A retrospective chart review revealed 11 patients who underwent reconstruction with a free fibula at The Hospital for Sick Children from 1990 to 2000. Radiographic and photographic studies were assessed for long-term growth of the reconstructed mandible, with follow-up ranging from 2 to 12 years. Results: Of the 11 patients who underwent reconstruction with a free fibula, two had surgery at skeletal maturity, two moved out of the country, one died as a result of her malignancy, and one was lost to follow-up. The remaining five patients are being followed by the craniofacial and orthodontic services and have not reached skeletal maturity. Of the two patients who have had orthognathic surgery, the one patient whose reconstruction involved the temporomandibular joint exhibited no growth on the reconstructed side and required a 57-mm advancement on the reconstructed side. The other patient, who had preservation of the temporomandibular joint at the time of reconstruction, required only a 5-mm advancement on the reconstructed side. Both patients had significant surgical complications as a result of the initial reconstructive techniques. Technical modifications necessary at the initial reconstruction became apparent when the authors performed a sagittal split osteotomy on the reconstructed side. Conclusions: Certain technical modifications to the original free fibula reconstructed pediatric mandible should be considered in anticipation of the need for a subsequent bilateral sagittal split at skeletal maturity.

Objective The purpose of this article is to describe a modified appliance and treatment approach for presurgical nasoalveolar molding in infants with unilateral cleft lip and palate. Methods This approach uses a plate held in with outriggers, which prevents the cleft-widening effect of the tongue, helps with tongue tip placement, and utilizes the functional movements of the facial musculature to guide and relocate the major segment medially to its normal position. Nasal molding is undertaken after most of the lateromedial correction of the alveolar position. Conclusions This technique helps to improve alveolar position, nasal septum alignment, nasal symmetry, and nasal tip projection prior to lip repair.

The aim of this cross-sectional anthropometric study was to determine the age-related changes in the facial framework during adulthood in healthy white North Americans of European ancestry (261 male subjects and 339 female subjects). Five measurements, four horizontal and one vertical, defining the framework were taken from the skin and bony surface of the face in the maturation period (16-20 years) and in 10-year age categories of adulthood (21-90 years). As well, the thickness of the soft-tissue cover between these two anatomical levels was measured. The categories between 21 and 40 years represented early adulthood, those between 41 and 70 years represented middle adulthood, and those between 71 and 90 years represented late adulthood. The forehead width in both sexes increased significantly on the skin and bony surface from the maturation period to early adulthood. In middle adulthood, the changes were significant only sporadically. In late adulthood, the upper and lower jaw showed a harmonious change with age, mostly increasing on both the skin and bony surface. The face width proved to be the most stable measurement and had the thinnest soft-tissue cover. No consistent pattern emerged during adulthood in increases or decreases within the facial framework; however, an unexpected harmony was noted between the values of the measurements in early and late adulthood in both sexes on both the skin and bony surface. The thickness of the soft-tissue cover at the bony landmarks was greatest in the midface, with a moderately decreasing tendency in both sexes. In the lower jaw, the soft tissue showed significant increases in thickness in early adulthood and moderate to large decreases in late adulthood. Anthropometric analysis of the facial framework in adulthood marks only the first step in establishing the morphological changes of the aging face. Quantitative evaluation of changes within the facial framework of the aging population must be carried out in more detail. Increased worldwide migration results in a mixing of people of various racial/ethnic origins and necessitates a general anthropometric analysis of the aging face to provide more reliable guidelines for therapy.

– Objectives: The aim of this study was to develop and evaluate the Family Impact Scale, a measure of the family impact of child oral and oro-facial disorders. This formed one component of the Child Oral Health Quality of Life Instrument©. Methods: The scale was developed using a process described by Guyatt et al. (1987) and Juniper et al. (1996). An item pool was developed using a review of existing child health status and family impact questionnaires, interviews with 41 parents–caregivers of children with paedodontic, orthodontic and oro-facial conditions and discussions with dental specialists. The resulting pool of 21 items was used in an item impact study in which 93 parents–caregivers provided data on the frequency and importance of these items. The 14 items identified most frequently or rated the most important were selected for the final questionnaire. The discriminant and construct validity and internal consistency reliability of this 14-item scale were assessed in a study of 266 parents–caregivers from the three clinical groups. Seventy-nine of these participants completed a second copy of the questionnaire to facilitate assessment of test–retest reliability. Results: Family Impact Scale scores ranged from 0 to 33, indicating that the measure was sensitive to variations in family impact. Floor effects were minimal with only 10.2% of subjects having a score of zero and there were no ceiling effects, that is, subjects with maximum scores. Almost three-quarters of parents–caregivers reported some family impact ‘sometimes’ or ‘often/everyday’ over the previous 3 months. Impact on parental or family activities of this frequency was reported by 53.0%, impact on parental emotions by 44.0%, conflict in the family by 31.6% and financial difficulties by 31.2%. The measure and its component items were reasonably good at discriminating between the three clinical groups included in the study and showed good construct validity. It had excellent internal consistency reliability with a Cronbach's alpha of 0.83 and was reproducible for parent–caregivers who reported that their child's condition was stable (ICC = 0.80). Conclusions: The study provides some data to suggest that child oral and oro-facial conditions have a pervasive impact on the family. The Family Impact Scale had good technical properties. Its evaluative properties need to be tested in longitudinal studies.

This study sought to determine the relative reliability of indirect cephalometric measurements and direct anthropometric ones taken in norma frontalis of 25 dry adult human skulls. Six of the 11 linear projective measurements were singular and located in the orbital, middle, and lower parts of the face, with two from each part. Two of the five paired measurements were taken in the orbital region on both sides, and the other three were taken in the middle to lower face between the midpoint of the facial axis and the landmarks lateral to it. Both singular and paired cephalometric distances were significantly shorter than the anthropometric distances. Mean numerical differences were much greater in paired measurements than in singular ones. The differences between these two sets of findings are a result of the uneven position of the landmarks used for measurement, located, as they are, on different planes of the face. These differences are undetectable by two-dimensional cephalograms.

Hemifacial microsomia is a hypoplastic disorder of the first and second branchial arches that significantly impacts on the development of the jaws, leading to malocclusion and facial asymmetry. There is little in the literature regarding the application of orthodontic/orthognathic approaches to the correction of these deformities and the stability of the surgical results. To address this, a retrospective chart review of 10 patients with complete orthodontic records and greater than 1 year of follow-up was performed. Posteroanterior cephalograms were assessed by modified Grummons analysis to determine mandibular offset (deviation of the chin point from the skeletal midline) and occlusal cant. These measurements were performed at 3 time points (T1: preoperative, T2: immediate postoperative, T3: follow-up) to elucidate the surgical movement (T2-T1), the postoperative relapse (T3-T2), and the net gain movement (T3-T1). Maxillary movements were quantified, and the occlusal cant was expressed as a ratio between vertical heights of the maxilla at the first molar on each side. One sample t test demonstrated statistically significant surgical movement and net gain. Relapse was statistically insignificant. Repeated-measures analysis of variance demonstrated similar results for chin point position relative to the putative midline. Our results suggest that a combined orthodontic/orthognathic approach at skeletal maturity delivers improved occlusal outcomes in the long term as assessed by chin point deviation and occlusal cant, but secondary surgery rates are higher than those for orthognathic surgery in other patient groups. We advocate limiting surgery to skeletal maturity whenever possible to achieve stable long-term results while limiting morbidity and number of procedures.

Objective To investigate associations between anthropometric lip measurements and dental arch relationships in patients with complete unilateral cleft lip and palate (CUCLP). Design Retrospective cross-sectional study. Patients Children with CUCLP. Methods Anthropometric lip measurements, made immediately prior to lip repair, were available for each patient. The dental arch relationships were evaluated on dental study casts (8.6 ± 0.9 years) taken prior to any orthodontic treatment and prior to alveolar bone graft, using the modified Huddart and Bodenham (MHB) scoring system. The presence of associations between anthropometric lip measurements and dental arch relationships was determined using linear regression analysis. Results In the 63 patients included in the study, the cleft lateral lip element was deficient in height in 87% and in transverse width in 86% of patients. Patients with more deficient cleft-side lateral lip height were more likely to present with more negative MHB scores ( r = .443; P < .001). Conversely, patients with more deficient cleft-side lateral lip transverse width more often presented with more positive MHB scores ( r = .281; P = .025). Conclusions In patients with CUCLP, there is a wide variability in the degree of deficiency of the cleft-side lateral lip element, both in the vertical and in the transverse dimension. The extent of this deficiency may, in part, predict the resulting dental arch relationships.

Objective: This study aimed to assess the ability of the Child Oral Health Quality of Life Questionnaire (COHQoL) to detect change following provision of orthodontic treatment. Methods: Children were recruited from an orthodontic clinic just prior to starting orthodontic treatment. They completed a copy of the Child Perception Questionnaire, while their parents completed a copy of the Parents Perception Questionnaire and the Family Impact Scale. Normative outcomes were assessed using the Dental Aesthetic Index (DAI) and the Peer Assessment Rating (PAR) index. Change scores and effect sizes were calculated for all scales. Results: Complete data were collected for 45 children and 26 parents. The mean age was 12.6 years (standard deviation = 1.4). There were significant pre-/posttreatment changes in DAI and PAR scores and significant changes in scores on all three questionnaires (P

In this retrospective longitudinal study, we aimed to study differences in the soft-tissue profiles in growing children with clefts in comparison with controls through the period of facial growth from 7 to 18 years.Lateral cephalometric measurements made at 7 years (T1), 11.1 years (T2), and 17.9 years (T3) of age of 70 white children (35 boys, 35 girls) with complete unilateral cleft lip and palate (UCLP) who received primary lip and palate repair surgeries at The Hospital for Sick Children, Toronto, were compared with those of a control group of similar ages, sexes, and racial backgrounds, and having skeletal Class I facial growth, selected from the Burlington Growth Study. None of the included subjects had received any surgeries other than the primary lip and palate repairs, and none had undergone nasal septum surgery or nasal molding during infancy. Between-group comparisons were made at each time point using generalized linear models adjusted for age and sex effects. Longitudinal comparisons across all time points were conducted using the mixed model approach, adjusting for these effects and their interactions with time.Bimaxillary retrognathism, progressive maxillary retrognathism, and increasing lower anterior face height with downward and backward growth rotation of the mandible in the UCLP group were seen. Unlike the hard-tissue face height ratio, their soft-tissue face height ratio was not affected. The upper lips in the UCLP group were shorter by 1.81 mm at T2 (P 0.001) and by 1.16 mm at T3 (P = 0.018), whereas their lower lips were 2.21 mm longer at T3 (P = 0.003). A reduced upper lip to lower lip length ratio at T2 and T3 (P 0.001) resulted. Their upper lips were relatively retruded by 1.44 mm at T1, 1.66 mm at T2, and 1.86 mm at T3 (all, P 0.001), and their lower lips were relatively protruded by 1.07 mm at T1 (P = 0.003), 1.40 mm at T2 (P 0.001), and 1.62 mm at T3 (P 0.001). Nose depths in the UCLP group were shallower by at least 1 mm from T1 to T3, and columellar length was shorter by almost 2 mm (all, P 0.001). Their columellae and nose tips rotated downward with growth, with the most significant rotations experienced from T2 to T3, and progressive reductions in their soft-tissue profile convexity were seen from T1 to T3 (P 0.001).Key attributes of the imbalance in the soft-tissue profile in children with repaired UCLP were identified in the lip and nose regions. Although many profile differences were visible as early as 7 years of age, they became more apparent by 11 years of age and increased in severity thereafter. The short upper lip combined with a long lower lip resulted in the characteristic lip length imbalance, whereas the progressively retruding upper lip and protruding lower lip led to developing a step relationship in the sagittal lip profile during the adolescent growth period. Their columellae and nose tips rotated downward during this time.

We reviewed the complications and long-term results of a consecutive series of adolescents (67 males, 49 females; age range 15 to 25 years; mean 18 years) born with a cleft who underwent primary repair in childhood and later developed a jaw deformity and malocclusion that required orthognathic surgery. Between 1986 and 1992, 116 adolescents with either unilateral cleft lip and palate (n = 66), bilateral cleft lip and palate (n = 33), or isolated cleft palate (n = 17) underwent an orthognathic procedure that included a Le Fort I osteotomy; 32 also underwent simultaneous sagittal split osteotomies of the mandible; and 87 underwent osteoplastic genioplasty. Clinical follow-up ranged from 1 to 7 years (mean 40 months) at the close of the study. The preoperative clinical examination varied according to cleft type and individual variation, but all patients had maxillary hypoplasia. Additional cleft-related deformities included residual oronasal fistula and bony defects, clefted alveolar ridges that retained dental gaps, and mobile premaxilla that lacked union to the lateral segments. Overall, 89 percent of residual fistulas underwent successful closure as part of the orthognathic procedure. Surgical cleft dental gap closure was achieved and maintained to the extent planned at 92 percent of the cleft sites. A fixed (prosthetic) bridge was used successfully for dental rehabilitation to close the gap in all other patients at each cleft site (n = 9). All patients with alveolar clefts (n = 99) maintained keratinized mucosa along the labial surface of the cleft-adjacent teeth (n = 264 teeth). Complications were few and generally not serious. There was no segmental bone loss of teeth because of aseptic necrosis or infection. Only 5 percent of cleft adjacent teeth underwent a degree of gingival recession and root exposure as a result of the maxillary osteotomy procedure; all were retained long term. The long-term maintenance of overjet and overbite measured directly from the late (> 1 year) postoperative lateral cephalometric radiograph indicated that 97 percent of patients maintained a positive overjet and 89 percent maintained a positive overbite; 5 percent shifted to a neutral overbite. The methods used to manage jaw deformity, malocclusion, residual oronasal fistula, and bony defects in adolescents born with a cleft are safe and reliable and offer the patient an enhanced quality of life. They also provide a stable foundation in which final soft-tissue lip and nose revisions may be carried out.

OBJECTIVE: To determine compliance with oral hygiene instructions (OHI) of adolescents receiving two-arch multibracket fixed appliances and identify its predictive factors. MATERIALS AND METHODS: Forty-one patients in a longitudinal study were provided standardized OHI and assessed at baseline: before bonding (T0mo), approximately 30 days after bonding (T1mo), and approximately 150 days (T5mo) after bonding straight-wire appliances simultaneously in the maxillary and mandibular arches. Oral hygiene (OH) performance was measured using plaque and gingival indices. Compliance predictors were identified from questionnaires administered to patients and their parents and from patients' charts. RESULTS: OH performance worsened from T0mo to T1mo but then improved from T1mo to T5mo. At T5mo, 73% of the sample had good OH. Univariate analyses found perceived severity of malocclusion, school performance, and parental marital status to be significant predictors of good OH performance at T5mo. Multiple logistic regressions identified having married parents and good academic performance in school as significant predictors. CONCLUSIONS: In the sample studied, after initially worsening, compliance with OHI improved at 5 months after bonding. Adolescents with married parents and those reporting good academic performance in school were found more likely to have complied with OHI provided at baseline and to perform better OH.

Objective: To (1) document the prevalence and patterns of hypodontia (permanent tooth agenesis) in Down syndrome (DS) and (2) explore whether maxillary or mandibular hypodontia or simultaneous agenesis of all third molars was associated with differential alterations of the craniofacial morphology. Materials and Methods: Longitudinal panoramic radiographs of 25 white patients with DS (12 male, 13 female; mean age, 15.1 years) treated at The Hospital for Sick Children, Toronto, Ontario, Canada, were evaluated to document hypodontia. Cephalometric measurements of subjects with maxillary or mandibular hypodontia or agenesis of all third molars were compared with those of subjects without hypodontia in these regions using analysis of covariance adjusted for age, gender, and proportion of other missing teeth in the total number of missing teeth. Results: Hypodontia was seen in 92% of the sample when third molars were considered and in 56% when third molars were not considered. Hypodontia was more prevalent and severe in females. The most frequently agenetic teeth were maxillary and mandibular third molars . maxillary lateral incisors . mandibular second premolars . mandibular incisors . maxillary second premolars . maxillary second molars. Simultaneous agenesis of all third molars was seen in 52% of the sample. Maxillary hypodontia was not associated with significant regional craniofacial differences, while mandibular hypodontia was associated with decreased mandibular length and increased ramus:body ratio. Agenesis of all third molars was not associated with significant craniofacial differences. Conclusions: Hypodontia is widely prevalent in DS. The effect of the syndrome appears to be stronger than that of regional hypodontia in differentially altering the craniofacial morphology. (Angle Orthod. 2011;81:260–269.)

The characteristics of articulation errors made by subjects having a class II, class II with open-bite, class III, or class III with open-bite malocclusion were compared. Regardless of the type of occlusal defect, errors occurred primarily on the sibilants /s, z/ and "sh, ch, j, dz," which were characterized mostly by combined visual and auditory distortions. Errors on the stop consonants /p, b, m, t, d, n/ occurred less frequently and, in all cases, consisted of isolated visual distortions. The type of malocclusion had a specific influence on the nature of the sound error. Subjects having a class II malocclusion, with or without an open bite, were able to assume a variety of tongue and mandibular postures that allowed them to approximate an /s/ or /z/. These compensations did not occur in subjects with a class III malocclusion. In these cases, the tongue remained distal to the mandibular incisors, causing the air stream to scatter. This study suggests that certain groups of sounds were more susceptible to specific types of misproductions and to particular types of occlusal defects.

Introduction Rapid palatal expanders (RPEs) have attachments cemented to the teeth and a screw that covers the palate. Because of their position and relative size, RPEs can affect speech. Our objective was to assess speech perturbation and adaptation related to RPE appliances over time. Methods RPEs were planned for the treatment of 22 patients in the orthodontic clinic at the University of Toronto in Canada. Speech recordings were made at 6 time points: before RPE placement, after placement, during expansion, during retention, after removal, and 4 weeks after removal. The speech recordings consisted of 35 sentences, from which 3 sentences were chosen for analysis. Speech acceptability was assessed perceptually by 10 listeners who rated each sentence on an equal-appearing interval scale. The vowel formants for /i/ and the fricative spectra for /s/ and /∫/ were measured with speech analysis software. Repeated-measures analysis of variance with post-hoc paired t tests was used for statistical analysis. Results When the appliance was placed, speech acceptability deteriorated. Over time, the ratings improved and returned to baseline when the appliance was removed. For the vowel /i/, the first formant increased, and the second formant decreased in frequency, indicating centralization of the vowel. The formants returned to the pretreatment levels during treatment. For the fricatives (/s/ and /∫/), low-to-high frequency ratios indicated that the fricatives were distorted when the appliance was placed. The ratios returned to baseline levels once the appliance was removed. The results for the spectral moments indicated that spectral mean decreased and skewness became more positive. Repeated-measures analysis of variance showed significant effects for time for all acoustic measures. Conclusions Speech was altered and distorted when the appliance was first placed. The patients’ speech gradually improved over time and returned to baseline once the appliance was removed. The results from the study will be useful for pretreatment counseling of patients and their families.

OBJECTIVE: To test the null hypothesis that there is no difference between craniofacial measurements of individuals with Down syndrome (DS) and normal controls. MATERIALS AND METHODS: A cephalometric analysis including additional landmarks and measurements to study specific craniofacial features was undertaken on pretreatment cephalograms of 25 patients with DS (12 male, 13 female; mean age 15.1 years) treated at The Hospital for Sick Children, Toronto. Measurements were compared with those from cephalograms of racial groups age and gender matched, normal, Class I children, available from the Burlington Growth Center. Data were analyzed using paired t-tests. RESULTS: Large reductions were measured in the size and spatial relationships of craniofacial structures in the DS group. The greatest differences included a larger cranial base angle; reduced elevation of sella from FHP; reduced anterior and posterior cranial base lengths; reduced anterior and posterior face heights; smaller maxilla with reduced anterior basal and apical dimensions; and smaller mandibular ramus, body and symphyseal dimensions and proclined symphysis. Maxillary incisors were severely proclined and undererupted, while mandibular incisors were undererupted. Alveolar heights were reduced. Anterior open bite was frequently noted. Maxillary and mandibular planes exhibited forward rotation patterns, promoting overclosure. Mandibular hypoplasia was less severe than cranial base and maxillary hypoplasia. Hypodontia of one or more permanent teeth was found in 92% of the sample. CONCLUSIONS: The null hypothesis was rejected. Significant hypoplasia in endochondral, mesodermal, and ectomesenchymal derived structures of the cranium and face in subjects with DS was clearly evident. More severe platybasia than previously reported was found.

To assess the functional and psychosocial impact of oligodontia in children aged 11-14 years.Children aged 11-14 years with oligodontia were recruited from orthodontic clinics when they presented for orthodontic evaluation. All completed a copy of the Child Perceptions Questionnaire for 11- to 14-year olds, a measure of the functional and psychosocial impact of oral disorders. Information on the number and pattern of missing teeth for each child were obtained from charts and radiographs.Thirty-six children were included in the study. The number of missing teeth ranged from one to 14 (mean = 6.8). Just over three-quarters of the subjects reported experiencing one or more functional and psychosocial impacts 'Often' or 'Everyday/almost everyday'. Correlations between scale and sub-scale scores and the number of missing teeth were weak and nonsignificant.Children with oligodontia experience substantial functional and psychosocial impacts from the condition. When compared with other clinical groups, children with oligodontia appear to have worse oral health-related quality of life than children with dental decay and malocclusion, but better oral health-related quality of life than children with oro-facial conditions.

Introduction The aim of this study was to investigate the prevalence of tooth wear in adolescents with Class II malocclusion, compared with those with normal occlusion. Methods The sample consisted of dental casts obtained from 310 subjects, divided into 3 groups: group 1, 110 subjects with normal occlusion (mean age, 13.51 years); group 2, 100 complete Class II Division 1 patients (mean age, 13.44 years); and group 3, 100 half-cusp Class II Division 1 patients (mean age, 13.17 years). Dental wear was assessed by using a modified version of the tooth-wear index. The 3 groups were compared by means of the Kruskal-Wallis and Dunn tests, considering the frequency and the severity of wear on each surface of each group of teeth. The level of statistical significance was set at 5%. Results The normal occlusion group had statistically greater tooth wear on the palatal surfaces of the maxillary central incisors and the incisal surfaces of the maxillary canines than the corresponding surfaces in both Class II malocclusion groups. The complete and half-cusp Class II Division 1 malocclusion groups had statistically greater tooth wear on the occlusal surfaces of the maxillary second premolar and first molar, the occlusal surfaces of the mandibular premolars, and the buccal surfaces of the mandibular posterior teeth compared with the normal occlusion group. The half-cusp Class II Division 1 malocclusion group had significantly greater tooth wear on the incisal surfaces of the mandibular incisors compared with the complete Class II Division 1 malocclusion group. Conclusions Subjects with normal occlusion and complete or half-cusp Class II Division 1 malocclusions have different tooth-wear patterns. Tooth wear on the malocclusion subjects should not be considered pathologic but rather consequent to the different interocclusal tooth arrangement.

The objective of this study was to quantify the properties of commercially available nickel-titanium open-coil springs.Eleven springs from 3 manufacturers were tested 5 times over a 12-week period. A universal testing machine was used to measure the force generated when open-coil springs were compressed to half of their original length and then gradually allowed to decompress.The average forces generated at the initial recording session for uniformly wound springs from GAC International (Bohemia, NY) and 3M Unitek (Monrovia, Calif) were 19.3% to 42.7% and 9.7% to 38.8% below the manufacturers' labeled force levels, respectively. GAC's 100-, 150-, and 200-g stop-wound coils demonstrated statistically and clinically significant stepwise force degradation over the 12-week experimental period (P0.0001). GAC's uniformly wound light (100 g) coils generated the lowest load-deflection ratios (23.7 g/mm).Open coils might need to be compressed by more than one-third of their original length to produce the labeled forces. Uniformly wound coils generally produce lower load-deflection ratios and maximum forces, which are generally more acceptable for tooth movement.

Introduction The purpose of this research was to analyze craniofacial morphology and adolescent facial growth in subjects with Pierre Robin sequence (PRS). The research was conducted at the Center for Craniofacial Care and Research at The Hospital for Sick Children, Toronto, Ontario, Canada, and the Burlington Facial Growth Research Center, Faculty of Dentistry, University of Toronto. Methods Longitudinal lateral cephalometric tracings of 34 Caucasian subjects with nonsyndromic PRS were compared with those of unaffected control subjects, matched for age, sex, and ethnicity, and representing the range of occlusions in an untreated population. Cephalometric measurements were obtained before orthodontic treatment (age, 11.8 years) and after orthodontic treatment but before any surgical treatment (age, 16.6 years). Between-group differences of craniofacial measurements were analyzed with paired t -tests, and longitudinal growth differences were analyzed with analysis of variance (ANOVA) adjusted for the growth interval. Results Significant differences were noted, with the PRS group showing smaller cranial base length, shorter maxillary and mandibular lengths, increased palatal and mandibular plane inclinations, and more open mandibular flexure. Mandibular body length and height were smaller as were ramal length and width, anterior basal thickness, and chin thickness. The ramus-to-body ratio was greater. With growth, greater gains in anterior face and symphyseal height were seen, but the mandible showed less closure of its internal flexure. The maxilla and the mandible remained retrusive during adolescent growth, and the maxilla became more retrognathic. Mandibular morphologic differences persisted in spite of additionally adjusting for cranial base length in the analysis. Conclusions Subjects with PRS had reduced cranial base and maxillary and mandibular lengths. Mandibular deficiency was most pronounced in the body. Due to bimaxillary retrognathism, the maxillomandibular dysplasia was not significant. A vertical growth pattern worsened the profile. There was no evidence of adolescent mandibular catch-up growth.