Objective: To test the shear bond strength, surface characteristics, and fracture mode of brackets that are bonded to enamel etched with an erbium, chromium:yttrium-scandium-gallium-garnet (Er,Cr:YSGG) laser operated at different power outputs: 0.5 W, 1 W, and 2 W. Materials and Methods: Human premolars that had been extracted for orthodontic purposes were used. Enamel was etched with an Er,Cr:YSGG laser system operated at one of three power outputs or with orthophosphoric acid. Results: The shear bond strength associated with the 0.5-W laser irradiation was significantly less than the strengths obtained with the other irradiations. Both the 1-W and 2-W laser irradiations were capable of etching enamel in the same manner. This finding was confirmed by scanning electron microscopy examination. The evaluation of adhesive-remnant-index scores demonstrated no statistically significant difference in bond failure site among the groups, except for the 0.5-W laser-etched group. Generally, more adhesive was left on the enamel surface with laser irradiation than with acid etching.
Conclusion:The mean shear bond strength and enamel surface etching obtained with an Er,Cr: YSGG laser (operated at 1 W or 2 W for 15 seconds) is comparable to that obtained with acid etching.
The aim of this study was to investigate the relationship between Turkish university students' awareness of malocclusion, their satisfaction with their personal dental appearance, and the severity of their occlusal irregularities. The sample consisted of 841 randomly selected university students, 522 (62.1 per cent) males and 319 (37.9 per cent) females, aged 17-26 years (mean age, 21.91+/-1.92 years). A pre-tested questionnaire was used to assess the subjects' awareness of malocclusion and satisfaction with their personal dental appearance; the actual severity of malocclusion was determined using the Dental Aesthetic Index (DAI). Statistical analysis was carried out using chi-square for gender differences and Spearman rank-order correlation coefficients for awareness of malocclusion, satisfaction with personal dental appearance, and DAI scores. Analysis of variance and univariate analysis, with age and gender as the independent variables, were further used to analyse the data. Weak but statistically significant, negative, correlations were found between awareness of malocclusion and satisfaction at the following DAI scores: or= 36 (r= -0.477, P<0.001), and a statistically insignificant, negative correlation at a score of 31-35 (r= -0.102, P>0.05). A statistically significant association was found between DAI and awareness of malocclusion (r= -0.305) and satisfaction with dental appearance (r=0.234). There were no significant associations between the department in which the individuals studied and the investigated variables (P>0.05). DAI scores were significantly higher for females. Generally, no statistically significant gender differences were found in relation to DAI scores, awareness, or satisfaction (P>0.05). The findings of this study showed that age had a significant effect on satisfaction and gender on DAI score variation. Females had a greater need for normative treatment except in the 20- to 22-year-olds, and satisfaction decreased with age.
By this investigation, two treatment methods, which are currently used in clinical practice, will be evaluated, and the results will be useful for clinicians.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.