A comparative study of skeletal and dental stability between rigid and wire fixation for mandibular advancement.

This study examined the skeletal and dental stability after mandibular advancement surgery with rigid or wire fixation for up to 2 years after the surgery. Subjects for this multisite, prospective, randomized, clinical trial were assigned to receive rigid (n = 64) or wire (n = 63) fixation. The rigid cases received three 2-mm bicortical position screws bilaterally and elastics; the wire fixation subjects received inferior border wires and 6 weeks of skeletal maxillomandibular fixation with 24-gauge wires. Cephalometric films were obtained before surgery, and at 1 week, 8 weeks, 6 months, 1 year, and 2 years after surgery. Skeletal and dental changes were analyzed using the Johnston's analysis. Before surgery both groups were balanced with respect to linear and angular measurements of craniofacial morphology. Mean anterior advancement of the mandibular symphasis was 5.5 mm (SD, 3.2) in the rigid group and 5.6 mm (SD, 3.0) in the wire group. Two years after surgery, mandibular symphasis was unchanged in the rigid group, whereas the wire group had 26% of sagittal relapse. Dental compensation occurred to maintain the corrected occlusion, with the mandibular incisor moving forward in the wire group and posteriorly in the rigid group. However, at 2 years after surgery, when most subjects were without braces, the overjet and molar discrepancy had relapsed similarly in both groups.

Evaluation of orthodontists' perception of treatment need and the peer assessment rating (PAR) index.

This paper examines the relationship between orthodontists' subjective assessment of treatment need and objective measurements obtained during standardized intra- and extraoral examinations. Logistic regression modeling was used to develop predictive models of treatment need. Data were obtained from 1155 eighth-grade students by four orthodontists who used standardized examination forms to assess demographics, trauma, skeletal relationships, morphologic malocclusion traits, and mandibular function. At the conclusion of the examination, the orthodontist rated the subjective treatment need as none, elective, recommended, soon, or immediate. For some analyses, the categories were collapsed to represent no need and need. The peer assessment rating (PAR) index (American validated version) was computed from the clinical exam findings and scoring of dental models; PAR scores were used to document malocclusion severity and treatment difficulty. Spearman rank correlation coefficients quantified the relationship between PAR scores and need categories. Logistic regression analysis modeled treatment need using components of the PAR index as well as other variables. The components of these models, as well as sensitivity and specificity, were compared with malocclusion severity/treatment difficulty scores obtained from malocclusion assessments using the PAR index. The five subjective treatment need categories and the PAR index scores were significantly correlated (rho = 0.62, p<0.001). Significant differences were detected between the need and no need groups for all PAR components (p<0.001). PAR index scores and predicted probabilities from logistic regression models performed equally well for classification purposes (no need, need). The data suggest that the PAR index is highly correlated with orthodontists' subjective assessment of treatment need when that assessment is made in the absence of financial considerations and patient desires.

Psychological function in orthognathic surgical patients before and after bilateral sagittal split osteotomy with rigid and wire fixation.

A multisite randomized controlled trial was conducted to compare the psychological function of patients who undergo surgical correction of a Class II malrelation with bilateral sagittal split osteotomy with either wire or rigid fixation. Subjects were 31 male and 86 female patients referred by orthodontists. Psychopathological symptoms and psychological distress were measured with the Symptom Checklist-90 Revised at the following times: before placement of orthodontic appliances, 1 to 2 weeks presurgery, and 1 week, 8 weeks, 6 months, and 2 years postsurgery. Patients' satisfaction with their surgical outcome was measured with a 3-item questionnaire. Results showed no statistically significant differences in psychological function or satisfaction between patients treated with wire or rigid fixation. Psychological function was within normal limits immediately before surgery. Psychological parameters did not determine patient satisfaction, even among patients who met an operational definition of "psychopathological caseness." Psychological symptoms and general distress increased modestly immediately after surgery for both groups and then progressively declined over the succeeding 2 years, eventually reaching levels that were significantly lower than presurgical levels. It was concluded that (1) rigid and wire fixation do not differ in their effects on psychological function and satisfaction; (2) patients who seek orthognathic surgery for a Class II malocclusion are psychologically healthy, ie, comparable to normal populations, immediately before surgery; (3) presurgical psychological function does not determine satisfaction with surgical outcome; and (4) psychological function tends to improve during the 2 years after surgery.

Condylar position with rigid fixation versus wire osteosynthesis of a sagittal split advancement.

PURPOSE: In this randomized clinical study, two groups of patients who underwent a bilateral sagittal split osteotomy and either wire osteosynthesis or rigid fixation were compared. PATIENTS AND METHODS: Cephalometric radiographs obtained before surgery, immediately after surgery, and at 8 weeks, 6 months, and 1 and 2 years after surgery were available for 125 of these patients, 63 with wire fixation and 62 with rigid fixation. All were traced by an independent examiner, and vertical and horizontal changes in condylar position were recorded for each period. RESULTS: Condylar movement was slightly different with the two fixation techniques beyond 8 weeks postsurgery, but the ultimate position of the condyle was not different. The condyles in both groups moved posterior and superior. There initially was a correlation between the amount of advancement and the amount the condyle moved inferior in both groups, but this diminished with time. In addition, there was a weak but significant positive relationship between forward rotation of the proximal segment and superior condylar position immediately after surgery, which did not exist at later periods. CONCLUSIONS: Whether wire osteosynthesis or rigid fixation was used, the ultimate condylar position was posterior and superior after a bilateral sagittal split osteotomy to advance the mandible. No single factor could be identified to account for this change. It is suggested that change in mechanical load may have resulted in remodeling and adaptation of the condyles.

Occlusal traits and perception of orthodontic need in eighth grade students.

In 1994, 1155 eight-grade students in Alachua County, Fla., were asked about self-perception of and level of concern for their occlusal status. Clinical assessments of orthodontic parameters were also recorded. Twenty-five percent of the students had a history of orthodontic treatment. Of the remaining students who had no history of orthodontic treatment, 74% reported satisfaction with the way their teeth looked, 64% expressed no perceived need for braces, and 57% were judged clinically to have optional or no orthodontic needs. Sex, soft tissue profile, overjet, anterior crowding, and molar classification were significantly associated with the perception of need for braces while race and overbite were not. Clinical judgment of orthodontic need differed significantly among levels of satisfaction with teeth. Eighth graders with no history of orthodontic treatment were generally satisfied with the appearance of their teeth and perceived less need for braces than clinicians.

Health-related quality of life following orthognathic surgery.

A randomized controlled trial was conducted to compare the effects of rigid and wire fixation on health-related quality of life following surgical mandibular advancement in patients with Class II malocclusions. Sixty-four patients randomly selected to receive rigid fixation with bicortical position screws were compared with 63 patients randomly selected to receive nonrigid fixation with inferior border wires. Quality of life was measured using the Sickness Impact Profile, a generic measure of health-related quality of life, and the Oral Health Status Questionnaire, a specific measure of oral health and function designed for use with orthognathic surgery patients. Patients were evaluated prior to application of orthodontic appliances, approximately 2 weeks before surgery, and 1 week, 8 weeks, 6 months, 1 year, and 2 years following surgery. Neither instrument revealed a statistically significant difference in quality of life between wire and rigid fixation at any time period. The health-related disability associated with Class II malocclusion is modest compared to many other medical conditions. Nonetheless, orthognathic surgery patients exhibit progressive and statistically significant improvement in health-related quality of life across a wide variety of functional domains, regardless of the fixation method used.

Anteroposterior skeletal and dental changes after early Class II treatment with bionators and headgear.

In this study we examined anteroposterior cephalometric changes in children enrolled in a randomized controlled trial of early treatment for Class II malocclusion. Children, aged 9.6 +/- 0.8 years at the start of study, were randomly assigned to control (n = 81), bionator (n = 78), and headgear/biteplane (n = 90) treatments. Cephalograms were obtained initially, after Class I molars were obtained or 2 years had elapsed, after an additional 6 months during which treated subjects were randomized to retention or no retention and after a final 6 months without appliances. Calibrated examiners, blinded to group, used Johnston's analysis to measure anteroposterior cephalometric changes. Statistical analysis was used to determine annual skeletal and dental changes during treatment, retention, and follow-up, and overall. Our data reveal that both bionator and head-gear treatments corrected Class II molar relationships, reduced overjets and apical base discrepancies, and caused posterior maxillary tooth movement. The skeletal changes, largely attributable to enhanced mandibular growth in both headgear and bionator subjects, were stable a year after the end of treatment, but dental movements relapsed.

Alveolar bone turnover and tooth movement in male rats after removal of orthodontic appliances.

The purpose of this study was to acquire tooth movement, histomorphometric and biochemical data on oral tissues that had previously been loaded with calibrated orthodontic forces. One hundred and forty-four male Sprague-Dawley rats were randomly divided into two groups: Group I, orthodontic appliances placed for 16 days to mesially move maxillary first molars with an initial force of 40 gm, and group II, sham orthodontic treatment. Seven to twelve rats were killed at each of six times after removal of appliance. Tooth movement was measured cephalometrically, alveolar bone turnover by histomorphometry, and tissue phosphatase levels biochemically. Treated molars moved distally more rapidly than the shams (13.9 vs 5.0 microns/day). The appliance removal group had a persistent 10-fold elevation in root resorption on the mesial (p < 0.0001), as well as early elevations in osteoclasts on the mesial and osteoblasts on the distal (p < 0.001) that returned to control by 3 to 5 days. Acid, alkaline phosphatase, and tartrate-resistant acid phosphatase (TRAP) remained elevated in the tissues until 10 days (p < 0.0001). Changes in the dynamic measures of bone formation were characterized by low rates at days 1 and 3 (p < 0.01), elevating thereafter on the mesial and the converse on the distal. Orthodontic tooth movement relapses, and bone remodeling continues for several days after removal of appliance consistent with the direction of loading, orthodontic treatment stimulates root resorption at sites that were loaded in pressure without detectable recovery, and root resorption does not increase at the tension sites.

A comparison of questionnaire versus monofilament assessment of neurosensory deficit.

PURPOSE: Because neurosensory deficit is commonly reported by patients after orthognathic surgery, it is important to know how accurately patients can report their own sensory deficit. This analysis compares the results of objective neurosensory tests with the results of a subjective patient questionnaire. MATERIALS AND METHODS: Before and 6 months after bilateral mandibular sagittal ramus split osteotomy, 101 patients with class II facial deformities were asked to rate sensations of numbness or tingling in the area of the mental nerve. Simultaneously, they were objectively tested using monofilament neurosensory tests (light touch and brush stroke direction). RESULTS: More than 70% of patients subjectively reported neurosensory problems, but objective assessment identified neurosensory deficits in less than 60% of the patients. The sensitivity and specificity of the patients' subjective assessments were 75.3% and 52.8%, respectively, for the light touch test, and 77.9% and 59.8%, respectively, for the brush stroke test. CONCLUSIONS: It was concluded that when monofilament neurosensory testing is used as the gold standard, patients appear to overreport neurosensory problems; ie, the positive predictive value of patient reports is only 63.2%, resulting in frequent false positives.

The measurement of acid and alkaline phosphatase in gingival crevicular fluid during orthodontic tooth movement.

This study examines acid and alkaline phosphatase activities in gingival crevicular fluid (GCF) to learn whether bone turnover dynamics can be monitored in human subjects during orthodontic tooth movement. Three female subjects were observed longitudinally to assess tooth movement, plaque, and inflammation. For each subject, one randomly selected premolar served as the control and was not treated, and another was moved buccally with 100 gm of force. The GCF was collected weekly and assayed for phosphatases. Alkaline phosphatase peaked between the first and third weeks, followed by an increase in acid phosphatase between the third and sixth weeks. After the first week, tooth movement averaged 0.9 mm. Additional 0.9 mm of movement occurred during the next 3 weeks, followed by 1.4 mm during weeks 4 to 6. Thirty additional patients, randomly divided into headgear/biteplate, bionator, and control groups, were also sampled cross-sectionally at the maxillary first molars. The GCF phosphatase activities were assessed as functions of location on the tooth, treatment modality, duration of treatment, gingival inflammation, and plaque accumulation. The plaque index did not show a relationship to either acid or alkaline phosphatase activity on the mesial or distal in the treated groups. However, alkaline phosphatase increased with inflammation on the distal in treated groups and acid phosphatase was consistently higher on the mesial than on the distal in the treatment groups. Alternating peaks of acid and alkaline phosphatase were found in the GCF of treated teeth as functions of treatment duration. The sequence of these changes is similar to that reported for alveolar bone turnover in a rodent orthodontic tooth movement model. We conclude that phosphatase activities in GCF may be a useful means for monitoring tissue responses to orthodontic treatment.

Skeletal change at surgery as a predictor of long-term soft tissue profile change after mandibular advancement.

PURPOSE: This study examined the time course of hard and soft tissue changes after mandibular advancement surgery and the association between skeletal changes as a result of surgery and subsequent soft tissue changes. PATIENTS AND MATERIALS: Subjects were enrolled in a randomized clinical trial of rigid versus wire fixation after sagittal split ramus osteotomy, with cephalometric data obtained before orthodontics, immediately before surgery and at 8 weeks, 6 months, 1 year, and 2 years postsurgery. This early report describes changes in 20 Caucasian female subjects who had completed all phases of the study; these were not segregated by fixation method. Cephalometric changes were referenced to a cranial base coordinate system. Differences in soft and hard tissue changes among time intervals were examined using analysis of variance; the associations between immediate surgical change in chin landmarks and subsequent short- and long-term soft and hard tissue changes were examined using linear regression analysis. RESULTS: Soft and hard tissue mandibular structures were positioned anteriorly and inferiorly during surgery; the horizontal and vertical hard tissue mandibular changes were stable for 2 years after surgery (P > .30), as were the vertical soft tissue changes (P > .08). There was horizontal relapse of the lower lip and the inferior sulcus (P < .03) by 8 weeks; no horizontal relapse was detected in soft tissue chin points for up to 2 years after surgery. The time course of changes in osseous pogonion was more strongly predicted by the amount of surgical osseous chin change than were changes in soft tissue chin projection. CONCLUSIONS: Prediction of changes in soft tissue chin projection after mandibular advancement surgery is less certain as time from surgery increases and less certain than the prediction of changes in bony chin projection.

Signs of temporomandibular disorders in patients with horizontal mandibular deficiency.

This study assessed the relationship between temporomandibular disorders (TMD) and malocclusion in a group of 102 patients with horizontal mandibular deficiency who had elected mandibular advancement surgery. The prevalence of TMD as reflected by the overall Craniomandibular Index, Dysfunction index, and Muscle index scores was within the range of non TMD populations (mean Craniomandibular Index = 0.14; mean Dysfunction index = 0.12; mean Muscle index = 0.15). Forty-two percent of the patients exhibited essentially no signs of TMD, 7.8% had primarily muscle tenderness to palpation, 36.3% had joint sounds with or without temporomandibular joint tenderness, and 13.7% had combined muscle-joint signs. There were no convincing correlations among any of the cephalometric variables and Craniomandibular Index, Dysfunction index, and Muscle index scores. A subgroup of 30 of this patient population was evaluated both before and during orthodontic treatment just prior to surgery. No statistically significant changes were found in Craniomandibular Index, Dysfunction index, or Muscle index scores. Thus, a period of orthodontic treatment in these patients does not appear to increase the probability of TMD.

Risk factors associated with incisor injury in elementary school children.

This study examined risk factors associated with incisor injury in 3396 third and fourth grade school children in Alachua County, Florida. One of six orthodontists completed a standardized examination form for each child to assess severity of incisor injury, gender, age, race, skeletal relationships, morphologic malocclusion, incisor exposure, interlabial gap, TMJ sounds, chin trauma, and history of lower facial trauma. One in five (19.2%) exhibited some degree of incisor injury. This was limited to a single tooth in 73.1% of those with injury, while enamel injury predominated (89.4%). The majority of the injuries (75.4%) were localized in the maxillary arch, with central incisors the most frequently traumatized. Chi-square tests of association indicated that gender, race, school, orthodontist, history of lower facial trauma, chin trauma, profile, and maxillary and mandibular horizontal positions were associated with incisor injury (P < 0.05). Wilcoxon rank sum tests identified differences in age, overjet, time of screening, and interlabial gap between those with and without injury (P < 0.05). Results of logistic regression analyses indicated risk of incisor injury was greater for children who had a prognathic maxilla, a history of trauma, were older, were male, and had greater overjet and mandibular anterior spacing.

Imprecision in orthodontic diagnosis: reliability of clinical measures of malocclusion.

The study examined the reliability among seven orthodontists in judging dental and facial aspects of malocclusion in a screening of elementary schoolchildren. Data included measures typically recorded during a clinical orthodontic examination: facial assessment of skeletal/incisor relationships and individual measures of morphologic malocclusion. Interexaminer reliability data were collected on 52 children. Pairwise comparisons between orthodontists were made using exact percent agreement and agreement within one category. Kappa statistics and one-sided Z-tests were used to evaluate observed agreement compared with agreement that would be expected by chance. Median Kappa statistics indicated that the reliability of maxillary and mandibular anteroposterior positions, incisor exposure, interlabial gap, and maxillary crowding was poor (K < 0.40). Acceptable reliability existed for mandibular anterior crowding, facial convexity, overbite, overjet, and molar classification (median Kappas ranged from 0.48 to 0.72). Excellent reliability existed only for evaluating the presence of a posterior crossbite (K = 0.79). The results caution that the language of clinical orthodontic diagnosis is imprecise.

Temporomandibular disorders after early Class II treatment with bionators and headgears: results from a randomized controlled trial.

Symptoms and signs of temporomandibular disorders were assessed in children enrolled in a randomized controlled trial of early treatment for Class II malocclusion. Children (mean age of 9.8 years) were assigned to a treatment protocol (bionator, n = 60; observation, n = 60; headgear/bite plane, n = 71) using randomized block stratification. Temporomandibular joint (TMJ) sounds, joint capsule pain to palpation, and muscle pain to palpation were scored as binary responses (present/absent in a subject). Determinations were made by blinded, calibrated examiners initially (DC1) and after a Class I molar correction was achieved or 2 years had elapsed (DC3). Univariate relationships among explanatory factors (group assignment, gender, age, time interval between DC1 and DC3, Class II severity, mandibular plane angle, preparatory treatment, whether Class I molar relation was achieved) and binary responses were explored using Chi square tables and ANOVA methods. Logistic regression modeled the relationship between binary responses and the explanatory variables. At DC1, the 3 groups were equivalent in the explanatory variables (P > .05). Subjects with a TMJ sound, joint pain, and/or muscle pain at follow-up were more likely those who had the sign at baseline (P < .01). Early treatment with bionators and headgear/bite planes did not place healthy children without these signs at risk for developing these signs. Only increasing age (for the development of sounds, P < .04) and failure to achieve a Class I molar relation (for development of muscle pain, P < .04) placed sign-free children at greater risk. Subjects with TMJ pain at baseline were 7 times more likely to have pain at follow-up if they had been treated with a headgear/bite plane or observed than if they had been treated with a bionator (P = .007). We conclude that an immediate benefit or risk for children receiving early Class II treatment with bionators and headgear/bite planes with respect to temporomandibular joint function does not exist with the prospect that Class II children with TMJ capsule pain may benefit from bionator therapy.

Alveolar bone turnover in male rats: site- and age-specific changes.

BACKGROUND: This study compares alveolar bone turnover adjacent to distally drifting maxillary first molar teeth of rapidly and slowly growing rats. METHODS: Two groups of forty male rats (1 and 3 months) were sacrificed. Sera were analyzed for acid (AcP), alkaline (AlkP), and tartrate-resistant acid phosphatase (TRAP). Bone histomophometry was done on parasagittal sections of maxillary molars. Molar drift was quantified cephalometrically. RESULTS: Distal surface contained more osteoclasts and higher osteoclast percents than mesials at both ages (P < 0.001). There were also more osteoclasts on the distals of the older rats as compared to the young (P < 0.001). Osteoblast percents were higher (P < 0.001) in the older rats on both surfaces. Mesials had higher double-labeled surface, MAR and BFR than distals in the younger rats (P < 0.001). The younger rats had higher (P < 0.001) AlkP, AcP, and TRAP. There were no age-specific differences in rate of molar drift. A model of rate of molar drift (P < 0.0015) containing bone formation measures accounts for 54.9% of the variability. CONCLUSIONS: We conclude that the bone turnover dynamics adjacent to maxillary first molars represent predominantly remodeling on the distal in both groups and modeling on the mesial only in the young rats, that distal molar tooth drift reflects alveolar bone turnover, and that alveolar bone manifests the marked reduction in bone cell activity that occurs in the rat skeleton after 8 weeks but that this reduction is compensated by recruitment or maintenance of more bone cells at these sites.

Orthodontic bone remodeling in relation to appliance decay.

This study examined alveolar bone turnover and orthodontic tooth movement after appliance decay. One group of rats (N = 54) received orthodontic force (40 g initial activation) while the other (N = 36) was sham-treated. Groups of six rats were sacrificed at various times following activation. Tooth movement and appliance decay were monitored cephalometrically, and bone turnover was monitored locally by histomorphometry and phosphatase chemistries and systemically by serum phosphatase and osteocalcin changes. A significant association was found between spring forces assessed by direct measurement and by cephalometric images (R2 = 0.784; p = 0.02). The cephalometric method indicated appliances were at least 93% deactivated by day 16. Tooth movement continued beyond the point of appliance decay (p < 0.001). This was accompanied by a dramatic decline in osteoblast surface (p < 0.0001) and an increase in osteoclast surface to control levels (p < 0.001). A significant peak in bone formation rate was also noted around appliance decay (p = 0.005). Serum acid phosphatase and osteocalcin also increased after appliance decay (p < 0.05), but alkaline phosphatase did not. Bone acid phosphatase was characterized by a peak after appliance decay (p = 0.0004), but alkaline phosphatase remained depressed (p < 0.0001). These data demonstrate that significant amounts of alveolar bone turnover continue for an indeterminant period following appliance decay.

Evaluation of a training program intended to calibrate examiners of temporomandibular disorders.

The adequacy of a training program intended to calibrate examiners of temporomandibular disorders (TMD) was evaluated. Eight examiners blindly rated 12 subjects with various TMD signs and symptoms after participating in a 5-h intense training procedure. Some examiners had earlier experience of TMD examinations, and some were newly trained. The Craniomandibular Index was used as the assessment instrument. Agreement within the whole group of examiners was low. Training tended to increase the probability of correctly registering signs. It is concluded that the program was not sufficient to create reliability among multiple examiners. More extensive training, not only to a standard but also between the different examiners, appears necessary. Revision of the examination technique is suggested, and recommendations for strengthening the calibration procedures are made.

Orthodontic treatment demand and need in third and fourth grade schoolchildren.

There have been few reports worldwide addressing orthodontic need and demand in children and no recent reports in the United States. The purpose of this study was to examine the orthodontic need and demand in third and fourth grade children (n = 3696). Data including age, sex, race, orthodontic status, socioeconomic status, availability of specialist treatment services, as well as thorough occlusal data, were collected. Orthodontic demand was significantly higher in girls (9.5%) than boys (6.8%), whereas need had the inverse relationship (41.8%, 44.2%, respectively). There were no meaningful differences in age among the demand, need, and no need groups. Demand was greater in white than in black children (11.8% versus 1.2%); however, need was observed to be less in black (35.3%) than in white children (47.2%). Demand was greater in the urban schools (8.9%) than in the rural schools (6.3%), whereas need was found to be similar. There was more demand in the higher socioeconomic groups (11.7%) than in the lower groups (1.8%), whereas need was similar in all the groups. The demand group had a significantly greater number of orthodontists within a radius of up to 5 miles of the school than the need and no need groups. Logistic regression models to examine factors that distinguish the groups show that when demand versus need/no need groups are compared, those students with an increased "risk" of previous treatment are more likely to have more orthodontists nearby, to be in higher socioeconomic groups, and to be female students.

Risk factors associated with temporomandibular joint sounds in children 6 to 12 years of age.

The relationship between temporomandibular joint (TMJ) sounds and a person's dental and skeletal characteristics is poorly understood. In this study, data were obtained from 3428 grade schoolchildren (mean age = 9.0 years, SD = 0.8, range 6 to 12 years), without a history of orthodontic treatment. Each child had been examined independently by one of six orthodontists to assess: TMJ sounds (none, click, crepitus), gender, age, race (white/black), skeletal relationships (convexity, maxillary, and mandibular positions), malocclusion (molar class, overjet, overbite, anterior crowding, posterior crossbite), maximum opening, chin trauma (none, cut, scar), and history of lower facial trauma. Temporomandibular joint sounds were present in 344 children (10.0% of the sample); 276 (8.1%) had an isolated unilateral sound, 254 (7.4%) had unilateral clicking, 50 (1.5%) had bilateral clicking, 22 (0.6%) had unilateral crepitus, and 11 (0.3%) had bilateral crepitus. Univariate analyses compared children with and without sounds for each variable; logistic regression analyses examined the relationship between groups of variables and TMJ sounds. The prevalence of TMJ sounds was associated with examiner (chi 2 = 23.4, df = 5, p < 0.001); increased prevalence of TMJ sounds occurred in children with maxillary anterior crowding (t = 2.8, p < 0.006), mandibular anterior crowding (t = 3.0, p < 0.002), and increased maximum opening (t = 4.7, p < 0.001). In contrast to other reports on children, the prevalence of joint sounds was not associated with age, race, gender, or molar class.(ABSTRACT TRUNCATED AT 250 WORDS)