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.

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.

One hundred and ten subjects (52 males and 58 females) between 23-28 years of age with dental Class I occlusal relationship, good soft tissue profile, and Caucasian ethnicity were selected from the population of dental students at the University of Zagreb, Croatia. The soft tissue facial profiles were digitally analyzed using linear (11 vertical and 14 horizontal) measurements made with standardized photographic records, taken in natural head position, to determine average soft tissue facial profile for males and females. The application of Student t-test showed gender dimorphism in most parameters of the labial, nasal. and chin areas. Almost all vertical variables were larger in the males, except the length of the nasal tip, which was larger in females. In the height of the vermilion, no gender dimorphism was observed. The females exhibited shallower labial sulci than the males and their chins were at least as prominent as those of the males. This study showed that male chins are not absolutely more prominent than female chins, but only appear to be such because their labial sulci are deeper.

Of this study was to analyze Shear Bond Strength (SBS) and Adhesive Remnant Index (ARI) of ceramic and metallic orthodontic brackets bonded to zirconia or lithium-disilicate ceramics used for prosthetic restorations, conditioned with hydrofluoric acid (HFA) or phosphoric acid (PhA), as well as to determine the Porcelain Fracture Index (PFI), in order to examine the condition of the ceramic surface after debonding. The research was conducted on 96 prepared all-ceramic samples divided into 8 groups combined from the type of ceramic material, orthodontic brackets, and surface conditioning. SBS was tested with Universal Testing Machine, and the samples were analyzed using a Scanning Electron Microscope, to determine ARI and PFI. Statistical data were processed using ANOVA, with the level of significance α = 0.05. Lithium-disilicate showed better bond strength in almost all groups. However, no significant difference between the groups was noticed and none of the factors had a significant influence on the mean values of SBS (p>0.05). Nevertheless, ARI significantly depended on the type of bracket (p = 0.005), and PFI significantly depended on the type of etchant (p = 0.029). The use of HFA for surface etching of zirconia and lithium-disilicate, does not cause a significant increase in the SBS values as compared to etching with PhA and silane application. Furthermore, HFA can weaken the surface structure of the ceramic, and considering its toxicity, might not be the best suitable conditioner prior to orthodontic bonding to lithium disilicate, and in particular to zirconia, also taking into account its crystalline structure.