Caries experience, obesity and demographic factors in school children: A cluster analysis.

OBJECTIVE: To determine the association between caries experience, obesity, and socioeconomic and environmental factors in 2, 5 and 12 years-old schoolchildren. Secondarily, the influence of school infrastructure was assessed. METHODS: Primary data from 1762 schoolchildren from the municipality of Cajamar (SP, Brazil) and socioeconomic and environmental secondary data (Brazilian Census 2010, School Census, Prova Brasil/2017) were used. Caries and treatment experience (dmft/DMFT indices), dental occlusion, visible biofilm, weight and height were assessed. RESULTS: Caries experience was found in 6.5%, 40.2% and 46.5% of children at 2, 5 and 12 years, respectively. At 12y, greater caries experience was observed among children financially assisted by the Bolsa Família governmental program. Excess weight was found in 30%, 35% and 34% at 2, 5 and 12 years. At 2 and 5 years, the highest dental caries indices were associated with disadvantageous socioeconomic indicators (households water supply and sewage system, garbage collection, literate head and income), while overweight was associated with female sex and better socioeconomic aspects. At 12y, the group with obesity was characterized by low dmf+DMFT index and better household aspects, while the group with greater dmf+DMFT index comprised normal-weight children. A correlation between the percentage of caries experience and student/employee ratio of the school was observed. CONCLUSION: An association between disadvantageous socioeconomic and environmental aspects and dental caries was observed, while obesity was associated with better socioeconomic status of the schoolchildren. While no direct association was found between obesity and dental caries, the results emphasize the influence of socioeconomic/environmental variables on health outcomes.

Relationship between orofacial function, dentofacial morphology, and bite force in young subjects.

OBJECTIVE: The aim was to evaluate the relationship between orofacial function, dentofacial morphology, and bite force in young subjects. SUBJECTS AND METHODS: Three hundred and sixteen subjects were divided according to dentition stage (early, intermediate, and late mixed and permanent dentition). Orofacial function was screened using the Nordic Orofacial Test-Screening (NOT-S). Orthodontic treatment need, bite force, lateral and frontal craniofacial dimensions and presence of sleep bruxism were also assessed. The results were submitted to descriptive statistics, normality and correlation tests, analysis of variance, and multiple linear regression to test the relationship between NOT-S scores and the studied independent variables. RESULTS: The variance of NOT-S scores between groups was not significant. The evaluation of the variables that significantly contributed to NOT-S scores variation showed that age and presence of bruxism related to higher NOT-S total scores, while the increase in overbite measurement and presence of closed lip posture related to lower scores. Bite force did not show a significant relationship with scores of orofacial dysfunction. No significant correlations between craniofacial dimensions and NOT-S scores were observed. CONCLUSION: Age and sleep bruxism were related to higher NOT-S scores, while the increase in overbite measurement and closed lip posture contributed to lower scores of orofacial dysfunction.

Evaluation of oro-facial function in young subjects with temporomandibular disorders.

The aim of this study was to evaluate bite force (BF) and oro-facial functions at different dentition phases (initial-mixed, intermediate-mixed, final-mixed and permanent dentition) in children and adolescents diagnosed with temporomandibular disorders (TMDs). The sample was selected from four public schools in Piracicaba, São Paulo, Brazil. Of the 289 participants recruited, aged 8-14 years old, 46 were placed into the TMD group. TMD was diagnosed using Axis I of the Research Diagnostic Criteria for Temporomandibular Disorders (2011). Oro-facial functions were evaluated using the Nordic Orofacial Test-Screening (NOT-S), which involves both an interview and a clinical examination. BF was measured using a digital gnathodynamometer. Age and body mass index (BMI) were also considered. The data were analysed by the following tests: Kolmogorov-Smirnov test, Student's t-test, Spearman and Pearson coefficients, Qui-square test, Fisher's exact or binomial test, as indicated. Moreover, univariate and multivariable logistic regression were applied. For the TMD group, scores associated with NOT-S interview and NOT-S total were higher than for the control group (P = 0.033 and P = 0.0062, respectively). No differences in BF between genders or groups (P > 0.05) were detected. Variables included in the multivariate logistic regression were BMI and NOT-S total. Based on this analysis, NOT-S total was associated with TMDs. Reported sensory function was the specific domain within NOT-S interview that established the significant difference between the groups (P = 0.021). The TMD group also had a greater number of alterations in the face-at-rest domain of the NOT-S exam (P = 0.007). Concluding, it did not detect an association between TMDs and either dentition phase or BF. Instead, BF correlated with age and BMI. Oro-facial dysfunction was associated with TMD in the studied sample, but this association may be bidirectional, requiring further researches.

Associations between psychological factors and the presence of deleterious oral habits in children and adolescents.

OBJECTIVES: This study aimed to evaluate the associations between psychological factors and the presence of deleterious oral habits in children and adolescents. STUDY DESIGN: 147 students aged 8 to 14-years-old were divided in two groups concerning the presence and absence of DOH Habit group (HG) and Habit free group (HFG). Participants were asked about the presence of DOH using the domain III (Oral Habits) of the Nordic Orofacial Test-Screening (NOT-S). Symptoms of anxiety and depression were evaluated using the Brazilian Portuguese versions of the Revised Children's Manifest Anxiety Scale (RCMAS) and the Children's Depression Inventory (CDI), respectively. Saliva was collected 30 min after waking and at night to determine the diurnal decline in salivary cortisol (DDSC). Data were analyzed using the Chi-squared, Mann-Whitney, Spearman's correlation and logistic regression. RESULTS: The prevalence of DOH was higher in females than males (65.1 vs 34.9; p < 0.05). The most frequent DOH was nail biting (58.7%). HG presented more depressive symptoms than HFG (p < 0.05). There was positive correlation between salivary cortisol levels and age (p < 0.01). Logistic regression analysis found association between symptoms of anxiety and the presence of DOH (OR = 2.35; p < 0.05). CONCLUSIONS: In conclusion, children and adolescents with DOH presented more symptoms of depression than their counterparts. Moreover, they were more likely to report symptoms of anxiety.

Changes in the oral-health-related quality of life of Brazilian children after an educational preventive programme: an 1-month longitudinal evaluation.

OBJECTIVE: This 1-month longitudinal study assessed whether the oral status and the oral-health-related quality of life (OHRQoL) of children changed after four sessions of an educational preventive programme. STUDY POPULATION AND METHODS: Fifty Brazilian students (11-12 year old) were examined for signs and symptoms of gingivitis using the Community Periodontal Index and two questions about gingival bleeding. The OHRQoL was measured using the Brazilian Portuguese version of the Child Oral Impacts on Daily Performances (Child-OIDP). Higher scores indicated worse OHRQoL. The results were analysed using the Shapiro-Wilk, Chi-square, Wilcoxon signed-rank and Mann-Whitney tests. The magnitude of the mean change was calculated using the effect size. RESULTS: Twenty-four percentage of children had more than six sites with bleeding at follow-up compared with 58% at baseline. There was a significant decline in the intensity and extension of impacts at follow-up. A significant improvement in the clinical status and oral hygiene was observed for both transitional categories. There was a significant decline in the Child-OIDP scores of those reporting 'much improved'. A significant improvement in the global ratings of oral health was observed at follow-up. CONCLUSIONS: In the studied sample, an improvement occurred with respect to the severity of disease, intensity and extension of impacts and global ratings of oral health after 1-month follow-up. These results suggest that improving the global transition in health by enhancing coping and management skills while inducing slight changes in the clinical status and the specific aspects of health compromised by the disease is possible.

Associations between oral health-related quality of life and emotional statuses in children and preadolescents.

OBJECTIVES: To evaluate the associations between oral health-related quality of life (OHRQoL) and emotional statuses in children and preadolescents. METHODS: One hundred and forty-five Brazilian students (8-14 years) were clinically examined for caries, gingivitis, fluorosis, malocclusions, and temporomandibular disorders (TMD). OHRQoL was measured using two global ratings of oral health (OH) and overall well-being (OWB). The Revised Children's Manifest Anxiety Scale (R-CMAS) and Children's Depression Inventory (CDI) were used to assess anxiety and depression, respectively. Saliva was collected 30 min after waking and at night to determine the diurnal decline in salivary cortisol (DDSC). The results were analyzed using non-paired t test/one-way ANOVA, Pearson's correlation test, and multiple linear regression analyses. RESULTS: 11-14-year-old participants had higher CDI scores (P < 0.01) and DDSC concentrations (P < 0.001). Participants with fewer caries and without gingivitis had higher DDSC concentrations (P < 0.05). TMD patients had higher DDSC concentrations and OWB ratings (P < 0.001). Girls had higher Revised Children's Manifest Anxiety Scale (RCMAS) scores (P < 0.01). There was positive correlation between RCMAS and CDI scores and OWB ratings (P < 0.05). The OH model retained age (ß =0.312; P < 0.001) and the OWB model retained TMD (ß = 0.271; P < 0.001) and CDI scores (ß=0.175; P < 0.05). CONCLUSIONS: Children and preadolescents with poor emotional well-being are more sensitive to the impacts of OH and its effects on OWB.

Evaluation of masticatory performance and bite force in children with sleep bruxism.

The aim of this study was to evaluate the association between masticatory performance (MP) and bite force (BF) in children with sleep bruxism (SB) during the mixed dentition stage, considering also the occlusal characteristics. The sample was composed by 52 healthy children of both genders, aged 6-10 years. From those, 22 presented signs and symptoms of SB and 30 were the controls. SB diagnosis consisted of both parental report and presence of tooth wear. MP was evaluated by the individual's ability to communicate an artificial chewable test material for determining the median particle size (X50) and distribution of particles in the different sieves (b). BF was measured using a digital gnathodynamometer with fork strength of 8 mm. The results were submitted to descriptive statistics, Mann-Whitney and chi-square tests, Spearman's correlation and multiple logistic regression. Mean BF and X50 did not differ between groups with and without SB. A significant negative correlation was observed between BF and X50 only in the group of children with SB. Moreover, the logistic regression model showed an association between the presence of SB and higher b index. The other independent variables included in the model showed no association with SB. BF did not differ between children with and without SB. Besides, higher BFs in children with SB meant better MP; however, they were more likely to present chewed particles retained in the larger aperture sieves, consequently requiring more chewing cycles to break down the test material in smaller particles.

Masticatory performance and taste perception in patients submitted to cancer treatment.

The aim of this study was to analyse mastication and the sense of taste in 39 patients submitted to cancer treatment in different areas of the body and to compare these variables with those of 44 control individuals within the same age range. The following aspects were assessed: dental status (DMFT); stimulated and non-stimulated salivary flow; sense of taste (salty, sweet, bitter and sour); and masticatory performance (MP), through the calculation of X(50). Logistic regression models were established to test the association between the independent variables and cancer treatment. Cancer patients had lesser stimulated salivary flow, a smaller number of teeth and occlusal units, worse MP, higher salty, sweet and sour taste scores and a lower bitter taste score (P < 0·05). A significant positive correlation was found between MP and the DMFT index in both groups (P < 0·05), meaning that a lower DMFT index value denoted a smaller X(50) value (better masticatory performance). The logistic regression model revealed that patients who had undergone cancer treatment had a greater probability of exhibiting a smaller number of teeth, higher salty and smaller bitter taste scores (P < 0·05). It was concluded that patients who were submitted to cancer treatment presented oral physiology alterations when compared with control subjects at the same age range.

Salivary cortisol, alpha-amylase and heart rate variation in response to dental treatment in children.

OBJECTIVE: Anxiety and stress are usually related to the dental treatment situation. The objective was to investigate salivary cortisol and alpha-amylase levels (salivary biomarkers) and heart rate in children undergoing a minor dental procedure (dental prophylaxis). STUDY DESIGN: In total, 31 children (range 84-95 months) of both genders without caries or history of dental treatment/pain/trauma were selected. Three saliva samples were gathered: one prior to dental prophylaxis, one immediately after and one ten minutes later. Weight and height were assessed, and heart rate was evaluated prior to and during the procedure. Data were analyzed by correlation tests and t-test/Wilcoxon (alpha = 0.05). RESULTS: Higher cortisol and amylase levels were observed before prophylaxis compared to afterward. Cortisol and amylase levels did not show a significant correlation, nor did salivary biomarkers and body mass index. However, heart rate and amylase levels showed a significant positive correlation. CONCLUSIONS: In the studied sample, certain anticipation of the dental treatment was observed because higher cortisol and amylase levels were observed before, rather than after the event; moreover a significant correlation between amylase levels and heart rate was observed Thus, salivary biomarkers may be a valuable tool for evaluating anxiety-producing events, such as dental treatment, in children.

Evaluation of facial asymmetry and masticatory muscle thickness in children with normal occlusion and functional posterior crossbite.

AIM: The aim of this study was to evaluate facial asymmetry and the thickness of the masticatory muscles in young children with normal occlusion and functional posterior crossbite. METHODS: The sample comprised 72 children of both genders (64.71±7.04 months) in the primary and early mixed stage of dentition, divided into four groups: primary-normal occlusion (PriN; N=19), primary-crossbite (PriC; N=19), mixed-normal occlusion (MixN; N=27), and mixed-crossbite (MixC; N=16). The thickness of the masseter and anterior portion of the temporalis muscle at rest and during maximal clenching were assessed by ultrasonography. Facial morphology and asymmetry were evaluated by standardized front-view photographs, in which the following measurements were recorded: anterior face height (AFH), bizygomatic facial width (BFW), angle of the eye (AE) and angle of the mouth (AM) (interpupillary and commissure planes in relation to mid-sagittal plane, respectively). RESULTS: The results showed that muscle thickness did not differ significantly between the sides of the dental arches in all groups (paired t-test). Only the groups with normal occlusion presented significant positive correlation between AE and AM (Pearson's correlation test). In PriN, only body weight was significantly related to masseter thickness; in MixN, facial morphology contributed significantly to masseter thickness at rest and maximal clenching, while the covariates weight, height and age did not relate to muscle thickness (stepwise backward multiple regression). CONCLUSION: In the studied sample, children with crossbite presented greater facial asymmetry than those with normal occlusion, and a greater masseter thickness was related to larger faces in the mixed dentition.

Salivary cortisol levels in young adults with temporomandibular disorders.

AIM: Causes of temporomandibular disorders (TMDs) are multifactorial, involving both physical and psychological factors. The aim of this study was to evaluate the salivary cortisol levels in young adults with TMDs. METHODS: The Research Diagnostic Criteria (RDC)/TMDs were used to establish the diagnosis of TMDs regarding the physical (axis I) and psychological factors (depression and somatization; axis II). Young adults of both genders composed the TMDs males (21.7+/-2.21 years, n=10) and females (22.7+/-1.95 years n=10) groups, and 20 healthy matched controls composed the control male (22.5+/-1.96 years n=10) and female (22.4+/-2.17years n=10) groups. Saliva samples were collected immediately on awakening and at bedtime. The cortisol levels were measured by enzyme immunoassay. RESULTS: The female group with TMDs showed a significantly higher cortisol level (2.890+/-0.411 mg/dL) than the corresponding control group in the morning evaluation (2.470+/- 0.486 mg/dL). The depression scores were significantly higher for the female group with TMDs (1.3+/-0.18) in comparison with the control female (0.72+/-0.18) and male groups (0.51+/-0.13). The groups with TMDs showed significantly higher somatization scores (0.69+/-0.16 for males and 1.38+/-0.23 for females) in comparison with the controls (0.23+/-0.10 for males and 0.78+/-0.15 for females), these also being significantly higher for the females than males. CONCLUSION: It was concluded that cortisol levels are higher in TMDs in females, who had elevated depression and somatization scores. The results infer that the evaluation of salivary cortisol could be a promising tool in the diagnosis of TMDs associated with psychological factors.

Oral health-related quality of life in children: part I. How well do children know themselves? A systematic review.

OBJECTIVE: Paediatric oral disorders are likely to have a negative effect on the quality of life. Until recently, children's oral health-related quality of life (OHRQoL) was measured using parents as informants. Instruments have now been developed, which have demonstrated that with appropriate questionnaire techniques, valid and reliable information can be obtained from children. The aim of this study was to make a systematic review of the existing literature about child perceptions of OHRQoL and their validation. METHODS: A computerized search was conducted using Medline, ISI, Lilacs and Scielo for children's perception of OHRQoL. The inclusion criteria were: the articles should contain well-validated instruments and provide child perceptions of OHRQoL. RESULTS: From 89 records found, 13 fulfilled the criteria. All studies included in the critical appraisal of the project suggested good construct validity of overall child perceptions of OHRQoL. However, children's understanding of oral health and well-being are also affected by variables (age, age-related experiences, gender, race, education, culture, experiences related to oral conditions, opportunities for treatment, childhood period of changes, back-translating questionnaire, children self-perceived treatment need). CONCLUSIONS: The structure of children's self-concept and health cognition is age-dependent as a result of their continuous cognitive, emotional, social and language development. By using appropriate questionnaire techniques, valid and reliable information can be obtained from children concerning their OHRQoL.

Oral health-related quality of life in children: part II. Effects of clinical oral health status. A systematic review.

OBJECTIVE: Children are affected by numerous oral and orofacial disorders, which have the potential to compromise functioning, well-being and the quality of life (QoL). The purpose of this paper was to review the literature about children's clinical oral health status and health-related quality of life (HRQoL) and to assess the respective association. MATERIALS AND METHODS: The authors searched Medline, ISI, Lilacs and Scielo for articles from 1985 to 2007. The inclusion criteria were randomized, cross-sectional, longitudinal or retrospective studies that used well-validated oral health-related QoL instruments, children self-applied questionnaires and quantitative measurements of clinical oral health status. RESULTS: Of the 402 articles that were critically assessed, 12 studies were included in the critical appraisal of the project. CONCLUSIONS: There is a relationship between clinical oral health status and HRQoL in children. In the studies that suggested weak relationships between children's oral conditions and HRQoL, the explanations were low disease levels in the sample, the conditions under investigation may have caused immeasurably low levels of impact or the impacts were mediated by inter- and intravariables according to culture and education. Moreover, relationships between biological or clinical variables and HRQoL outcomes are not direct, but mediated by a variety or personal, social and environmental variables, as well as by the child development, which have influence on the comprehension about the relationship among health, illness and QoL. So, longitudinal studies are necessary to determine validity, responsiveness and minimal clinically important difference.

Oral health-related quality of life in children: part III. Is there agreement between parents in rating their children's oral health-related quality of life? A systematic review.

OBJECTIVE: One issue that receives a great deal of attention is the comparison between measurement of children's oral health-related quality of life (OHRQoL) reports with those of their parents. However, the extent to which parents understand the effects of ill-health on their children's lives remains unanswered. The purpose of this systematic review was to identify the literature on the nature, extent and the pattern of agreement/disagreement between parent and child reports about child OHRQoL and assess the association between them. MATERIALS AND METHODS: The literature was searched using MEDLINE, ISI, Lilacs and Scielo, from January 1985 to March 2007. The selected studies used well-validated instruments and provided children's and parent's perceptions of child OHRQoL. RESULTS: A total of 87 articles were retrieved and five were selected for the review, which showed that children and parents do not necessarily share similar views about child OHRQoL. Some parents may have limited knowledge about their children's OHRQoL, particularly the impact on social and emotional well-being. CONCLUSIONS: Valid and reliable information can be obtained from parents and children using appropriate questionnaire techniques. Although the parents' reports may be incomplete due to lack of knowledge about certain experiences, they still provide useful information.

Masticatory performance and bite force in relation to signs and symptoms of temporomandibular disorders in children.

AIM: The aim of this study was to compare and correlate the masticatory performance (MP) and maximum bite force (BF) in children with and without signs and symptoms of temporomandibular disorders (TMD). METHODS: Thirty-six children aged 7-12 years in the mixed or beginning of permanent dentition where divided into 2 groups: with signs and symptoms of TMD (SS group, n=21) and without signs and symptoms (Control group, n=15). The signs were evaluated in the clinical exam and the symptoms through a questionnaire. The evaluated criteria were: presence of postcanine teeth in occlusion, the Angle's classification for first permanent molars, canine relationship, crossbite, midline deviation, overbite and overjet. The MP was determined by chewing a silicone tablet during 20 cycles and the particles were analyzed by an optical system. The BF was determined by a pressurized transducer placed between the upper and lower permanent first molars. The statistical tests were Student's t, Mann-Whitney, Fisher's Exact and Pearson's correlation. RESULTS: MP and BF were statistically smaller for SS group. Body variables did not show significant differences between groups. There was no correlation among the variables within each group demonstrating that MP was independent on the BF, as well as BF and MP were independent on the body variables. There was no difference in the proportion on occlusal characteristics between groups. Overbite was significantly larger for SS group. CONCLUSIONS: It is possible to infer that signs and symptoms of TMD can interfere in the proper masticatory function and muscle strength in children.

Caries prevalence in 6-36-month-old Brazilian children.

The prevalence of dental caries was determined in 322 Brazilian children aged 6 to 36 months. The earliest age at which initial and manifest caries were recorded in children were 6-12 months and 13-18 months respectively. Sixty-five per cent of the children were caries free. Seventeen per cent of the affected children showed 46 per cent of the total caries lesions, which demonstrates the need for early identification of those children with a high caries risk.

Masticatory efficiency in children with primary dentition.

PURPOSE: The aim of this study was to evaluate masticatory efficiency in children with normal primary occlusion and malocclusion and to correlate efficiency with body variables. METHODS: Thirty children were divided into three groups: Group I with normal occlusion (n = 10), Group II with posterior crossbite (n = 10) and Group III with anterior open bite (n = 10). They chewed standardized silicone tablets for 20 strokes and the optical scanning system was used to calculate the particle size (area and perimeter). Results were compared among the groups. Body weight and height were correlated with masticatory efficiency. RESULTS: Group I fragmented the tablets into a greater number of particles with smaller sizes than Groups II and III, and the differences were statistically significant (p<0.05). There was no difference between the children with crossbite and children with open bite. Correlation coefficients between body variables and masticatory efficiency were weak (p>0.05). CONCLUSIONS: Occlusion is a factor of influence on masticatory process.

Electromyographic evaluation of masticatory muscles at rest and maximal intercuspal positions of the mandible in children with sleep bruxism.

UNLABELLED: In adults, sleep bruxism (SB) may be related to reports of pain or fatigue in the muscles of mastication, resulting from multiple muscle contractions that occur during the night. In children, little is known about the consequences of this parafunction. PURPOSE: The objective was to compare the electromyographic activity (EMG) of the masseter and anterior portion of the temporalis muscles in children with and without SB; acquisitions were made at rest (RE) and in maximal intercuspal (MI) positions of the mandible. METHODS: Twenty children with signs and symptoms of SB (mean age 7.20 years ± 0.52) and 20 controls without signs or symptoms of SB (mean age 7.40 years ± 0.50) were selected. The controls were matched to the type of occlusal morphology evaluated according to Björk et al. (Acta Odontol Scand 22:27-40, 1964). Muscle activity was measured with the mandible at RE, MI and maximal clenching with cotton roll (MC), on the left and right sides. Data from the RE and MI (mV) were normalized by calculating them as % MC. The results were analyzed by descriptive statistics, Shapiro-Wilk test, Wilcoxon and Mann-Whitney tests. RESULTS: The subjects' age did not differ significantly between groups. EMG of temporalis muscle at RE differed between the right and left sides in both groups. There was no significant difference in EMG of masseter and temporalis muscles between groups. CONCLUSION: Children with SB showed no significant difference in EMG of masticatory muscles at RE and in MI positions of the mandible when compared with the control group.

Ultrasound and tomographic evaluation of temporomandibular joints in adolescents with and without signs and symptoms of temporomandibular disorders: a pilot study.

OBJECTIVES: Condylar position in the glenoid fossa has been linked to temporomandibular disorders (TMDs); however its importance in TMD aetiology is still unclear. The purpose of this study was to determine joint spaces and condylar position in adolescents with TMDs using ultrasound static images and linear corrected tomograms at the mandibular rest position. METHODS: Craniomandibular index (CMI) and a symptom questionnaire were assessed in 217 subjects aged 12-18 years. Those with the lowest and the highest scores were divided into control (n=20) and SSTMD (presence of signs and symptoms of TMD) groups (n=20). Ultrasound images and tomography were used to measure the distance between the capsule and the lateral surface of the condyle and to determine the condyle location at the mandibular resting position, respectively. RESULTS: The mean distances obtained from ultrasound images did not correlate with CMI scores and they did not differ between the two groups (P>0.05). Posterior positioned condyles were determined on tomograms, and they were more prevalent both in the SSTMD group (P=0.05) and in girls (P<0.05). CONCLUSIONS: Even though there was a significant difference in condyle position between the control and SSTMD groups, determined by axially corrected tomograms, it cannot be inferred that posteriorly positioned condyles can predict TMDs. In addition, there was no association between the articular capsule and the lateral condyle surface distances measured by ultrasound using a 10 MHz linear transducer and the clinical diagnosis of TMD. Further studies in diagnostic imaging of TMJs with ultrasound should be encouraged, since it has some useful diagnostic applications and does not require special facilities.

Molar bite force and its correlation with signs of temporomandibular dysfunction in mixed and permanent dentition.

The aim of the study was to evaluate molar bite force (BF) magnitude and its correlation to the signs of temporomandibular dysfunction (TMD), gender, weight, height and age in 101 students ranging in age from 6 to 18 years (32 boys/21 girls with mixed dentition and 23 boys/25 girls with permanent dentition). TMD clinical signs were evaluated using the Craniomandibular Index (CMI), and two subscales, the Dysfunction Index (DI) and the Palpation Index (PI). BF was determined with a pressurized tube connected to a sensor (MPX5700-Motorola SPS). anova, Tukey's test, and Pearson's and Spearman's coefficients were evaluated. BF was higher in the permanent dentition (P < 0.05). There was no difference in BF between genders within the groups, but boys with permanent dentition had higher values than children with mixed dentition (P < 0.05). The girls with permanent dentition presented negative correlation in BF with PI and CMI (P < 0.05). BF was positively correlated with weight, height and age in the permanent dentition group (P < 0.05). It was concluded that BF increased from mixed to permanent dentition, with an assumed enhancing influence of body variables and ageing. The TMD signs in older girls were correlated to decreasing BF, suggesting an influence of muscle tenderness preventing subjects from exerting maximum BF.