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The aims of this investigation were to determine whether stabilization of maximum voluntary bite force (MVBF) occurs between 15 and 18 years of age in subjects with a normal occlusion, and to assess the influence of gender, body mass index (BMI), morphological occlusion, and jaw function measured by the number of occlusal contacts, overjet, overbite, maximal mouth opening, mandibular deflection during opening, sagittal slide between the retruded contact position and the intercuspal position, and number of dental restorations. The sample comprised 60 Caucasian subjects aged 15 (15 males and 15 females) and 18 (14 males and 16 females) years with a neutral occlusion, balanced facial profile, and absence of a previous orthodontic history. Bite force measurements were undertaken using a portable occlusal force gauge on both the left and the right sides of the jaw in the first molar region during maximal clenching. Two independent samples t-tests and multiple regression were used for statistical analysis. MVBFs were age and gender related (P<0.05). Males showed a significant increase in bite force between 15 and 18 years of age (P=0.002), but gender differences were significant only in the 18-year-olds (P=0.003). In subjects with a neutral occlusion, MVBF could best be predicted using multiple regression from age and gender. The regression model accounted for 31.3 percent of the variance in MVBF (P=0.031), with gender contributing 17.9 percent and age 7.9 percent. Morphological occlusion, jaw function, and BMI explained the remaining 5.5 percent of variance. While controlling for all other parameters, the independent contribution of gender to the prediction of MVBF was 16.2 percent, age 6 percent, number of occlusal contacts 3.2 percent, and BMI 1.3 percent.

Summary: Patients' and parents' perception of malocclusion are important in determining orthodontic treatment demand, motivation, and cooperation. The aim of this study was to investigate differences in perception of treatment need in currently orthodontically treated, previously treated, and untreated subjects. The sample comprised 3196 children and adolescents (1593 males and 1603 females) aged 8-19 years (mean age 13.0 +/- 3.6 years) from 24 randomly selected public schools in Zagreb, Croatia. Objective treatment need was assessed clinically using the Dental Aesthetic Index (DAI). Subjective treatment need was estimated separately by an orthodontic resident, the child/adolescent and his/her parent using the Standardized Continuum of Aesthetic Need (SCAN) procedure. The children/adolescents completed a questionnaire that had five questions with five-point Likert-type scale answers concerning satisfaction with dental appearance, importance of teeth for facial appearance, and malocclusion-related quality of life. Spearman correlation and logistic regression were used for statistical analysis. Associations between objective and subjective orthodontic treatment need were weak but statistically significant (Rho from 0.20 to 0.50; P < 0.05). Malocclusion-related quality of life was poorly associated with treatment need. Satisfaction with tooth appearance showed the most frequent statistically significant correlation (Rho from -0.14 to -0.35; P < 0.05), while importance of aligned teeth for facial appearance and social contacts had the weakest correlation with treatment need. Perception of treatment need was greater in previously treated subjects. Parents' perception had a low predictive value. The findings of this study show that malocclusion has more impact on emotional well-being than on function or social contacts.

An appropriate relationship of the mesiodistal (MD) widths of the maxillary and mandibular teeth favours optimal post-treatment results. The aims of this study were to determine whether there is a difference in the incidence of tooth size discrepancies among different skeletal malocclusion groups and if gender dimorphism exists. The dental casts and lateral cephalometric radiographs of 301 Croatian subjects (127 males and 174 females, mean age 16.86 +/- 2.93 years) were selected from a larger sample of records of the archives of the Orthodontic Department, School of Dental Medicine, University of Zagreb, Croatia. The subjects were from malocclusion groups according to Angle classification, with the corresponding skeletal characteristics. The MD dimensions of all teeth from first molar to first molar were measured on the dental casts using digital callipers. Statistical analysis was undertaken using Kolmogorov-Smirnov, t, and Scheffé's tests and one-way analysis of variance. A statistically significant gender difference was found in anterior ratio (P = 0.017). A significant difference in the overall and posterior ratio was observed between Class II and Class III subjects. There was a tendency for mandibular tooth size excess in subjects with an Angle Class III malocclusion and for maxillary tooth size excess in those with an Angle Class II malocclusion. The percentage of subjects more than 2 standard deviations from Bolton's means for anterior and overall ratios was 16.28 and 4.32, respectively.

The aim of the present study was to determine the dental and occlusal features that could contribute to the aetiology of palatally displaced canines (PDCs). The material consisted of pre-treatment dental casts of 50 patients (36 females and 14 males) with unilateral and bilateral PDCs aged 14-16 years (mean 15.6 +/- 1.6 years). These were compared with a control group of 50 treated subjects (25 males and 25 females) of the same age with normally erupted maxillary canines. The following parameters were measured on the dental casts: the mesiodistal (MD) and buccolingual (BL) width of each maxillary tooth, the maxillary interpremolar and intermolar widths, overjet and overbite, dentoalveolar arch relationship (based on incisor classification), and missing or anomalous teeth. The differences between the PDC group and controls were determined using a Student's t-test. P values less than 0.05 were considered significant. PDCs occurred most frequently in subjects with a Class I occlusion. Sixteen per cent of the PDC subjects had congenital absence or peg-shaped lateral incisors or congenital absence of the second premolar, demonstrating a clear association between palatal impaction of the maxillary canine and anomalous or congenital tooth absence. The overjet was significantly smaller in the PDC female subjects, especially in those with unilateral impaction (P < 0.05). Overbite was significantly greater in PDC male subjects compared with the controls, especially in bilateral impaction cases. There was no statistically significant difference between the groups with regard to the maxillary transverse dimensions, maxillary MD widths, or palatal height for either gender.

An aesthetically pleasing and balanced face is one of the objectives of orthodontic treatment. An understanding of the soft tissues and their normal ranges enables a treatment plan to be formulated to normalize the facial traits for a given individual. The aim of this study was to evaluate the variables defining the soft tissue facial profile of a Croatian (Caucasian) sample, by means of angular measurements typically used for aesthetic treatment goals. Additionally, gender differences were tested. The soft tissue facial profiles of 110 dental students (52 males and 58 females) between 23 and 28 years of age at the University of Zagreb, Croatia, with a dental Class I occlusal relationship and harmonious soft tissue profile were studied by means of standardized photographs taken in the natural head position (NHP). To compare males and females, a Student's t-test was used. The reliability of the method was analysed using Dahlberg's formula. There were distinct gender differences. All angles were larger in females: nasofrontal (G-N-Nd, females = 139.11 degrees; males 136.38 degrees; P = 0.030), nasolabial (Cm-Sn-Ls, females = 109.39 degrees; males = 105.42 degrees; P = 0.018), mentolabial (Li-Sm-Pg, females = 134.5 degrees; males = 129.26 degrees; P = 0.019), and nasal tip angle (N-Prn-Cm, female = 84.12 degrees; male = 79.85; P = 0.001). The greatest variability was found for mentolabial angle. The findings demonstrate a distinct profile trait for female Croatian patients compared with male subjects.