Narasimha Prasad

CEPHALOMETRIC LANDMARKS IDENTIFICATION AND REPRODUCIBILITY : A META ANALYSIS

To assess the magnitude of cephalometric landmarks identification error, we performed a Meta analysis on six pertinent studies. We outline the procedures used to compare and integrate the findings of these-studies. The results are a measure of systematic and random errors involved when locating landmarks on lateral head films. They are presented as standard mean errors and 95% confidence intervals for the repeatability and reproducibility of 15 cephalometric landmarks commonly used in growth analysis.

Craniofacial asymmetry and temporomandibular joint internal derangement in female adolescents: a posteroanterior cephalometric study.

Unilateral or bilateral pathology of the osseous components of the temporomandibular joint (TMJ) can result in pronounced facial asymmetry because of dissimilar size and shape of the right and left sides of the mandible. To date, it is unknown whether abnormalities of the soft tissues of the TMJ are associated with greater than normal craniofacial asymmetry. In this study, we investigated the amount of craniofacial asymmetry in female orthodontic patients with unilateral or bilateral TMJ internal derangement (TMJ ID) relative to the amount in female patients without TMJ ID. The total sample consisted of 80 female adolescents. Bilateral TMJ magnetic resonance images were used as a database for objectively scoring the severity of TMJ ID. Craniofacial asymmetry was measured from posteroanterior cephalograms. Females with bilateral TMJ ID had significantly greater asymmetry in the vertical position of the antegonion. If the TMJ ID was more advanced on the right side, the ipsilateral ramus was shorter, resulting in significant asymmetry in this region. In all other craniofacial regions, the amount of asymmetry was not significant between females with normal TMJs and those with TMJ ID. The results indicate that a female orthodontic patient with bilateral TMJ ID or unilateral right TMJ ID may present with or develop a vertical mandibular discrepancy.

Assessment of facial asymmetries from posteroanterior cephalograms: Validity of reference lines

The goal of this study was to determine the ability of various horizontal and vertical reference lines to provide measurements of dentofacial asymmetries from posteroanterior (PA) cephalograms. Ten horizontal and 15 vertical reference lines, including best-fit lines and lines most commonly used in PA analysis, were tested. A model of a dry skull was devised to create 30 asymmetric positions of the maxillomandibular complex. The true transverse and vertical asymmetries were calculated based on measurements of changes in the position of 24 dental and skeletal landmarks. A PA cephalogram was obtained for each asymmetric position. The horizontal and vertical reference lines were constructed on each PA cephalogram, and measurements of transverse and vertical asymmetries were obtained relative to the individual reference lines. Linear regression analyses were used to compare the actual asymmetries with those measured cephalometrically, relative to the individual reference lines. The adjusted R(2) values for all 10 horizontal lines indicated excellent agreement between the true asymmetries and the measured vertical asymmetries. Ten vertical lines accurately represented transverse asymmetry. Vertical lines constructed between 2 midline points, with 1 point located on the lower part of the skull, were not valid. The best-fit line and all lines constructed as perpendiculars through midpoints between pairs of orbital landmarks showed excellent validity. Crista galli-anterior nasal spine and nasion-anterior nasal spine had the lowest validity and should not be used in cephalometric analysis of asymmetries. The position of anterior nasal spine will be altered in facial asymmetry involving the maxilla.

Parental cognitive impairment and child maltreatment in Canada

OBJECTIVES The aim of this study was to determine the prevalence of parental cognitive impairment in cases opened for child maltreatment investigation in Canada, and to examine the relationship between parental cognitive impairment and maltreatment investigation outcomes including substantiation, case disposition and court application. METHODS The method was secondary analysis of the Canadian Incidence Study of Child Abuse and Neglect (CIS-2003) core-data, which is derived from a multi-stage stratified cluster sample of 11,562 child maltreatment investigations. RESULTS Parental cognitive impairment was noted in 10.1% of sampled cases that were opened for child maltreatment investigation in 2003, and in 27.3% of sampled cases that resulted in child welfare court application. Neglect was the most common cause of concern. With child and case characteristics held constant, parental cognitive impairment predicted investigation outcomes. The data further suggest that the relationship between parental cognitive impairment and investigation outcomes was partially mediated by perceived parent non-cooperation, mental health issues and low social support. CONCLUSIONS The number of children who are living with a parent with cognitive impairment and who are referred for protective services is thought to be increasing. Building systems capacity to support parents with cognitive impairment and promote child wellbeing is therefore essential to containing the human and economic costs of maltreatment and out-of-home care. PRACTICE IMPLICATIONS A broad-spectrum approach is needed to support parents with cognitive impairment and their children. Equipping services with the knowledge, skills, and mandate they need to deliver evidence-based parent training is vital. However, strategies are also needed to tackle discrimination, alleviate family poverty, strengthen the social ties of parents with cognitive impairment and in turn, improve the life chances of their children.

Quantitative assessment of temporomandibular joint disk status

The purpose of this study was to quantify temporomandibular joint disk-slice information produced by magnetic resonance imaging by means of a stepwise discriminant analysis. One hundred ninety-four adolescents consented to magnetic resonance imaging evaluation of their temporomandibular joints. Sagittal magnetic resonance imaging slices of each joint were assigned to one of six subjective categories of disk position by an experienced maxillofacial radiologist. Standardized reference planes transferred to each magnetic resonance image from corresponding lateral cephalometric radiographics facilitated the measurement of disk length and disk displacement and the computation of ratio values of these measurements. Discriminant analysis revealed that all three quantitative variables were descriptive and discriminant for grouping slice data into pre-established subjective categories. Cross-validation and misclassification error calculations showed a 69.3% agreement between subjective and discriminant classification. Therefore quantification of disk displacement can be used in place of subjective evaluation. In addition, discriminant analysis disclosed a reduction in disk length associated with increased severity of disk displacement.

Correlations between condylar characteristics and facial morphology in Class II preadolescent patients

The aim of this retrospective study was to determine correlations between condylar characteristics measured from preorthodontic tomograms of preadolescents and their facial morphologic characteristics. The sample consisted of 136 patients displaying a Class II malocclusion, a vertical or horizontal skeletal growth tendency, and ranging in age between 10 years 0 months and 12 years 6 months for males and 9 years 0 months and 11 years 6 months for females. Two groups were established: the vertical group had 68 patients, 36 males and 32 females, (average pretreatment age, 11 years 0 months); the horizontal group also had 68 patients, 29 males and 39 females, their average pretreatment age was 10 years 9 months. The central cut of axially corrected lateral tomograms of the left and right temporomandibular joints for each group was randomized, blinded, and traced for condyle/fossa measurements including: anterior, superior and posterior joint space; condylar head and posterior condylar ramus inclination; condylar neck width; and condylar shape and condylar surface area. A logistic discriminant analysis with significance values set at p < 0.05 was used to determine the most reliable condylar characteristics to predict facial morphology. A cluster analysis was completed on the significant variables to form three clusters. Numeric ranges separating these clusters were then calculated. Chi-square tests measures of association were computed for significant variables and tested for associations between facial morphologic characteristics. Condylar head inclination and superior joint space proved to be significantly correlated to facial morphology (p values ranged from 0.010 to 0.018). Patients with vertical facial morphologic characteristics displayed decreased superior joint spaces and posteriorly angled condyles. Increased superior joint spaces and anteriorly angled condyles were significantly correlated to patients with a horizontal facial morphology. No significant correlations between the other condylar characteristics and facial morphology were determined.

Child Maltreatment Investigations Involving Parents With Cognitive Impairments in Canada

The authors examined decision making and service referral in child maltreatment investigations involving children of parents with cognitive impairments using the Canadian Incidence Study of Reported Child Abuse and Neglect (CIS-2003) core-data. The CIS-2003 includes process and outcome data on a total of 1,243 child investigations (n = 1,170 weighted) in which parental cognitive impairment was noted. Employing binary logistic regression analyses, the authors found that perceived parent noncooperation was the most potent predictor of court application. Alternative dispute resolution was rarely utilized. The findings from this study highlight the need for development and utilization of alternative dispute resolution strategies, worker training, dissemination of evidence-based parent training programs, and implementation of strategies to alleviate poverty and strengthen the social relationships of parents with cognitive impairments and promote a healthy start to life for their children.

TMJ internal derangement and adolescent craniofacial morphology: A pilot study

Intrinsic and extrinsic factors influence the growth of mandibular condylar cartilage. Local environmental factors, such as temporomandibular disc displacement, may alter condylar cartilage growth resulting in facial changes. The aim of this study was to determine if there was an association between identifiable altered craniofacial morphology and disc displacement. Magnetic resonance imaging (MRI) was employed to determine disc position in 25 preorthodontic adolescent patients (mean age 12.8 years, range 10 to 17 years). Magnetic resonance imaging and lateral cephalometric radiography were performed with the teeth held in centric occlusion by means of a polyvinylsiloxane bite registration. Radiographs were traced and variability between tracings within patients was insignificant for all variables (p > 0.04) except Co-Go, S-Go, and SN/Go-Me (p < 0.01). For each patient, 10 linear, 4 angular, and 3 ratio measurements were compared with an age- and sex-matched population in the Craniofacial Growth Series. Multiple regression analysis showed positive and negative associations between disc displacement and cephalometric variables. R-square value was .91 for the left TMJ and .82 for the right. Disc displacement in an adolescent population may be associated with altered craniofacial morphology.

Five-Year Longitudinal Treatment Outcomes of the ISTAR Comprehensive Stuttering Program.

UNLABELLED Replicated evidence of satisfactory 1- and 2-year post-treatment outcomes has been reported for the Comprehensive Stuttering Program (CSP). However, little is known about longer term outcomes of the CSP. Yearly follow-up measures were obtained from 18 participants for 5 consecutive years. At 5-year follow-up, participants were maintaining clinically and statistically significant reductions in stuttering and increases in rates of speech relative to pre-treatment measures. Standardized effect sizes were large. There were no significant differences among the immediate post-treatment and five follow-up measures, indicating that speech gains achieved by the end of the treatment program were stable over the 5-year follow-up period. Insufficient return rates for self-report data for the third to fifth follow-up measurement occasions prohibited analyzing these data. However, non-significant differences among the immediate post-treatment and two follow-up measures indicated that improvements achieved by the end of treatment in speech-related confidence, and perceptions of struggle, avoidance, and expectancy to stutter were stable over the 2-year follow-up period. Significant differences among the speech-related communication attitudes scores indicated that improvements in attitudes made at the end of the treatment program were less stable. Taken together, these results provide further and longer term evidence of the effectiveness of the CSP. EDUCATIONAL OBJECTIVES Readers will be able to: (1) describe the main components of the Comprehensive Stuttering Program (2) describe a methodology for determining clinically meaningful maintenance of stuttering reductions, and (3) describe the durability and stability of improvements in speech and self-report measures across time.

Cervical electromyogram profile differences between patients of neck pain and control.

Study Design. A comparative analysis of electromyogram (EMG) signals of patients of cervical pain and normal controls. Objectives. To determine the differences between frequency and time domain parameters of EMG signals of patients of cervical pain and normal controls. Summary of Background Data. No diagnostic technique has emerged as a satisfactory tool for identification of spinal pain. Method. Seventeen male and 17 female chronic neck pain patients without cervical radiculopathy were recruited through neurology EMG clinic. The controls consisted of 30 male and 33 female subjects with no history of neck pain in the past 12 months. All subjects performed flexion, left anterolateral flexion, left lateral flexion, left posterolateral extension, and extension to pain threshold/20% maximum voluntary contraction and pain tolerance/maximum voluntary contraction in random order. The descriptive statistics for body weight normalized strength, normalized peak EMG, time to onset, time to peak, median frequency, mean power frequency, and frequency bands were calculated. These variables were subjected to analysis of variance and logistic regression to distinguish between patients and controls. Results. The normalized peak EMG of patients was significantly greater than those of controls in both maximal and submaximal exertions (P < 0.01). Whereas there was no consistent pattern in time to peak EMG, the time to onset of EMG revealed that the left sternocleidomastoid was always recruited before the onset of torque. A lack of significant difference in the median frequency of the 2 samples indicates that the pain did not disturb the muscle conduction velocity. Using discriminant logistic regression on frequency domain and time domain parameters, up to 97% of patients and controls were correctly classified with the resubstitution method. Conclusion. Surface EMG can be used successfully in distinguishing chronic pain patients and controls, and efficacy of treatment regimes.