Developing and modifying the policies of orphanages requires the availability of accurate information. This study aimed to compare caries and oral hygiene status among orphan and non-orphan children. This descriptive cross-sectional study took place in governmental orphanages and schools of both genders in Mashhad, Iran. The prevalence of caries was assessed using the Decayed, Missing and Filled Tooth (DMFT) index, and oral health status was assessed using the Oral Hygiene Index – Simplified (OHI-S). The results were statistically analyzed using a t-test and Chi-Square test. The mean DMFT was 3.36 in orphans and 2.10 in non-orphan children, which was not statistically significant (p=0.6). The mean dmft was 9.01 in the orphan group and 5.26 in the non-orphan group, which was statistically significant (p=0.003). The average OHI-S index was 2.30 in the group of orphan children and 1.05 in the non-orphan children, presenting a statistically significant difference (p=0.00). The prevalence of caries, especially in deciduous teeth, was high among orphan children. The oral health status of these children was worse than that of children living at home. Consequently, there is a need for proper planning to promote the oral health of children living in orphanages.

Background To compare the shear bond strength of brackets with and without enamel etching. Material and Methods In this study, 60 sound premolars were randomly divided into four different groups: 1- TXE group: Enamel etching+Transbond XT adhesive+ Transbond XT composite. 2- TXS group: Transbond plus self-etch adhesive+ Transbond XT composite. 3- PQ1E group: Enamel etching+ PQ1 adhesive+ Transbond XT composite. 4- PQ1 group: PQ1 adhesive+ Transbond XT composite. The shear bond strengths of brackets were evaluated using universal testing machine at cross head speed of 0.5 mm/min. The Adhesive Remnant Index (ARI) was also measured. One-way ANOVA, Tukey’s post hoc, Kruskal-wallis and Mann-Witney U test were used for data analysis. Results There was a significant difference between etched and unetched groups respect to SBS and ARI (p<0.05), however; no significant difference was observed between unetched group and self-etch adhesive group (p>> 0.05). The shear bond strength of PQ1 group was the least but in acceptable range and its ARI was less than other groups. Conclusions PQ1 adhesive can be used for bracket bonding without enamel etching with adequate bond strength and minimal ARI. Key words:Bracket, shear bond strength, filled-adhesive, self-etch adhesive.