Fluctuating Dental Arch Asymmetry in Different Malocclusion Groups.

OBJECTIVE: To compare the degree of dental arch fluctuating asymmetry (FA) among patients with Class I, II, and III malocclusions. SUBJECTS AND METHODS: The sample comprised randomly selected plaster casts of 131 patients: 39 Class I (19 males and 20 females), 57 Class II (23 males and 34 females), and 35 Class III (20 males and 15 females). Dental models were scanned and digitized using ATOS II SO. The measurements of the teeth and dental arches were taken using the ATOS viewer version 6.A.2 software. Six arch widths and five arch depths were measured. The FA was assessed as a composite index of total weighted asymmetry (TWA). The analysis of variance was used to determine whether there were any statistically significant differences between the groups. RESULTS: Composite TWA measures of fluctuating asymmetry for dental arch variables were the highest in Class III, and lowest in Class I malocclusion. Males displayed a higher degree of asymmetry than females. The asymmetry degree was higher in the mandibular dental arches than in the maxillary dental arches in all malocclusion groups. CONCLUSION: The TWA values were low but they differed significantly between the groups of malocclusion. Class III malocclusion displayed higher FA values than Class I and Class II malocclusion. Higher FA of dental arches in Angle's Class III can be considered an indicator of increased developmental instability in this malocclusion due to high levels of genetic and environmental stress during the period of early development.

Importance of interincisal index for predicting mesiodistal crown diameters of canines and premolars.

The aim of this study was to examine the accuracy of regression equation for prediction of the mesiodistal diameter (MDD) of the crowns of canines and premolars (C, P1, P2), and to determine whether an incisal indexs can serve as a reliable predictor. MDD and vestibulooral diameter (VOD) of the crowns of central and lateral incisors (I1, I2), C, both P1, and P2, and first permanent molars (M1) in both jaws were measured on the plaster casts of 150 subjects (75 boys and 75 girls). The obtained measurements were compared and correlated with predicted values (by linear regression equation derived previously), with respect to gender, jaw side and value of the interincisal index. The correlation coefficients between measurements and predicted MDD of the C, P1, and P2 were calculated with respect to gender and jaw. The values varied from 0.62 to 0.81. It could be concluded that normal values of the interincisal index of the I1 and I2 are highly associated with measured and predicted MDD of the C, P1, and P2 crowns. Correlation coefficients ranged from 0.84 to 0.99.

Correlation between the pattern of facial growth and the position of the mandibular third molar.

PURPOSE: The purpose of this study was to examine the correlation between variables that determine the position of the third molar (M3) and correlation between the pattern of facial growth and examined variables. MATERIALS AND METHODS: Material for the study consisted of 130 panoramic radiographs and lateral radiographs of subjects' heads in whom orthodontic therapy had been started. Analysis of the position of the mandibular M3 and its relation to the bone and other teeth were determined by 4 variables: evaluation of the space for both M3, spatial relation between the second molar and M3, vertical position of the M3 in relation to the alveolar ridge, and inclination of the germ of the M3. RESULTS: In boys, significant correlation was determined on the right side of the jaw, between the retromolar area and the vertical position of M3. Significant correlation was determined in girls, between the retromolar area and the vertical position of M3 on both sides, retromolar area and M3 inclination on the left side, and retromolar area and spatial relation of M3 on the right side. Analysis of correlation between facial growth pattern and 4 variables that determinate the position of M3 showed positive correlation only for the lower right M3 inclination in subjects with anterior facial rotation. CONCLUSION: The present study showed that the amount of retromolar space for the position of the M3 is not a sign of its normal development. No significant differences were determined between the position of M3 and type of facial growth.

Structural analysis of dental fear in children with and without dental trauma experience.

The aim of the study was to evaluate dental fear in children with and without dental injuries in a randomly selected children in Croatia (59 girls and 88 boys). Children were divided into three groups depending on dental trauma experience. They were also divided into two age groups: 5-8 and 9-12 years. Only dental trauma to the permanent teeth was included in the study. The CFSS-DS, CDAS and CMFQ were used for evaluation of dental anxiety and the ISP Hollingshead Index of Social Position was calculated for evaluation of social status. The mean values of CDAS, CFSS-DS and CMFQ tests revealed that the anxiety level decreases with increasing experience of dental injury. The analysis of variance performed for CDAS showed a significant difference between children with and without dental trauma (p = 0,010). Regarding the groups, the analysis of variance for CMFQ (p = 0,021) and CFSS-DS (p = 0,001) showed a significant difference, as well as regarding age (CMFQ; p = 0,001 and CFSS-DS; p = 0,016). Cronbach's alpha coefficients revealed the highest reliability for CFSS-DS (alpha = 0,910). Pearson's correlation coefficients revealed significant correlations between the anxiety scores, age and ISP values for children without dental trauma, and between the anxiety scores and age for children with repeated dental trauma. The results of the ISP Hollingshead Index exhibited the highest frequency in children with dental injuries who belonged to the families with poor social background (ISP = 44-60). No significant difference was obtained between children with and without dental injuries depending on either gender or the ISP value.