The Effect of Educational Status on the Perception of Social and Spontaneous Smiles.

OBJECTIVE: The aim of the present study was to evaluate the effect of educational status on the perception of smile esthetics considering social and spontaneous smile patterns. METHODS: The present study was conducted on 110 subjects with differing educational status. Of 110 subjects with a mean age of 39.4 years, 30 were primary school graduates, 30 were high school graduates, and 50 had a university or higher educational level. Four different black and white natural social and spontaneous smiling images, captured from a video recording of a 25-year-old female, were prepared displaying the full-face and oral area. A 10-cm visual analog scale (VAS) was used to evaluate the smile esthetics. RESULTS: There were significant differences in the social and spontaneous smiles in a subjective assessment of the smile esthetics in full-face and oral views between participants having a different educational status (p>0.05). Compared with the other groups, the participants in the primary school graduate group gave higher esthetic scores in all the image groups. In terms of esthetic perception, this group was followed by high school graduates and participants with a university or higher level of education. In the four image groups, there was a significant difference between the primary school graduates and participants with a university or higher level of education (p<0.05). CONCLUSION: Educational status is a sociodemographic factor that can affect the perception of smile esthetics. The esthetic scores both in social and spontaneous smile decrease with increasing education level, and the most remarkable difference exists between primary school graduates and those with university or higher level of education.

Dimensional changes of the nasal cavity after transpalatal distraction using bone-borne distractor: an acoustic rhinometry and computed tomography evaluation.

PURPOSE: The aims of this study were as follows: 1) evaluation of the effects of transpalatal distraction (TPD) on nasal minimum cross-sectional area (MCA) and nasal volume, and assessment of long-term stability of TPD outcomes on the nasal cavity, using acoustic rhinometry (AR); 2) quantifying the alveolar, basal, and nasal components of the maxillary expansion at both canine and molar levels by computed tomography (CT); 3) investigation of the relationship between CT transverse measurements and AR measurements. PATIENTS AND METHODS: The sample was comprised of 11 adult patients with maxillary transverse deficiency and partial/near total nasal obstruction. Standard corticotomies were carried out and bone-borne transpalatal distractors were used in all cases. AR recordings were used to determine nasal minimum cross-sectional area of the anterior (MCA1) and posterior (MCA2) and the volume of the nasal cavity in these regions (Volume1, Volume2) before surgery (T1), when the distractor was removed (T2), and at least 1 year after the expander was removed (T3). CT images were taken at T1 and T2. CT measurements included maxillary base, alveolar, and nasal cavity widths at both canine and first molar slices. RESULTS: There were significant increases in MCAs and volumes of nasal cavity between T1 and T2 and between T1 and T3 with the exception of the right MCA2 and right Volume2 at the latter time (P < .05). All maxillary transverse dimensions in canine and molar CT slices displayed significant increases (P < .05). The change in binasal width at the canine level showed significant correlations with the changes in total MCA1 and total Volume1 (P < .05). CONCLUSION: TPD provided great increases in MCA and volume of the nasal cavity, and these changes generally remained stable long term. The use of TPD in adult patients granted the opportunity of efficient maxillary expansion concurrent with increases in the nasal dimensions.

Conservative rehabilitation of missing teeth before placement of implant dentures: clinical reports.

Although implant-supported restorations often are preferred for the replacement of missing teeth, their high cost means that they can be given only to patients who can afford them. The clinical reports in this article describe interim conservative restorations made after orthodontic treatment to achieve esthetics, phonation, and function until implant-supported dentures were made. In all cases, the patients who received fiber-reinforced resin composite fixed partial dentures returned for follow-up visits at three-month intervals and reported no complaints during a year of follow-up visits. The desired esthetics can be achieved with temporary conservative treatment until the implant dentures are applied; if this treatment meets the patient's esthetic expectations, the final restoration can be fabricated according to these contours.

Evaluation of the shear bond strength of 3 curing bracket bonding systems combined with an antibacterial adhesive.

INTRODUCTION: The purpose of this in-vitro study was to investigate the shear/peel bond strength of metal brackets bonded to human enamel with differently cured bonded systems combined with an antibacterial adhesive component. METHODS: One hundred twenty extracted molars were divided into 3 groups. Stainless steel brackets were bonded with 1 of 3 systems: group 1, no-mix bonding adhesive (Unite, 3M Unitek, Monrovia, Calif) (n = 40); group 2, 2-paste chemically cured bonding resin (Concise, 3M Unitek) (n = 40); and group 3, light-cured adhesive (Transbond XT, 3M Unitek) (n = 40). Each bonding group was separated into experimental (n = 20) and control groups (n = 20). In the 3 experimental groups, an antibacterial self-etch adhesive (Clearfil Protect Bond, Kurary, Osaka, Japan) was also applied to the enamel. Specimens in the control groups were bonded only with their relevant bonding systems according to the manufacturers' instructions. All specimens were stored in distilled water for 24 hours and thermocycled before testing. Debonded specimens were scored with the adhesive remnant index. RESULTS: The mean bond strengths (in megapascals) were 9.8 (control, 15.7) in group 1, 12.0 (control, 18.5) in group 2, and 11.6 (control, 12.4) in group 3. Statistical analysis with t tests showed no difference between group 3 and its control (P = .178), whereas groups 1 and 2 were statistically different from their controls (P = .000). CONCLUSIONS: The results indicated that the newly developed antibacterial self-etch adhesive can be combined with various bonding systems; achieved bond strengths were clinically more than satisfactory.

Relapse of anterior crowding in patients treated with extraction and nonextraction of premolars.

INTRODUCTION: The purpose of this study was to evaluate long-term stability of incisor crowding in orthodontic patients treated with and without premolar extractions. METHODS: Dental casts and cephalometric records of 98 patients were evaluated before treatment (T1), at posttreatment (T2), and at postretention (T3). Half of the patients had been treated with extractions, and half were treated nonextraction. RESULTS: Irregularity, as measured by the irregularity index, decreased 5.51 mm in the extraction group and 2.38 mm in the nonextraction group. Mandibular incisor irregularity increased 0.97 mm in the extraction group and 0.99 mm in the nonextraction group, respectively, in the postretention period. Maxillary incisor irregularity relapse was smaller than mandibular incisor relapse for both groups. Intercanine width expanded during treatment. At T3, mandibular intercanine width decreased in both groups, but the differences were not statistically significant. At T3, intermolar width was stable, arch depth decreased, overbite and overjet slightly increased, SN mandibular plane angle decreased, and incisor positions in both groups tended to return to T1 values. Clinically acceptable stability was obtained. CONCLUSIONS: With the exception of the interincisal angle, no statistically significant differences were recorded between the extraction and nonextraction groups from T2 to T3. No statistically significant correlations were found between any variables studied and mandibular incisor irregularity at T1, T2, and T3.

Smile esthetics: perception and comparison of treated and untreated smiles.

INTRODUCTION: Although orthodontic treatment is based primarily on occlusal relationships, greater attention is now paid to enhancing dentofacial characteristics to produce optimal facial esthetics. The purposes of this study were to compare smile esthetics among extraction and nonextraction patients and a control group, assess certain dentofacial characteristics in those groups, and discuss how these features relate to smile esthetics. METHODS: Panels of orthodontists, plastic surgeons, artists, general dentists, dental professionals, and parents used a 5-point scale to rate smiling photographs of 25 extraction, 25 nonextraction, and 25 untreated control subjects. Dentofacial characteristics of the 3 groups were obtained from lateral cephalometric analyses, direct biometric measurements, and frontal photographs. Smile esthetics and differences among the 3 groups were subjected to 1-way analysis of variance (ANOVA), and Pearson correlation coefficients were calculated to determine the relationship of the variables to the esthetic score. RESULTS: The mean esthetic scores for the extraction, nonextraction, and control groups were 3.15, 3.12, and 3.26, respectively. Visible dentition width relative to the smile width ratio and intercanine distance relative to smile width ratio were significantly different among the groups, with extraction patients showing a slightly wider dental arch relative to the soft tissue (P < .05). There was also a significant difference in the U1-SN angle among the groups (P < .05), and this variable showed a strong correlation with the esthetic score as did maxillary gingival display (P < .05). However, our study groups could not be differentiated in smile esthetics.