mitra shabanian

Along with development of different dental adhesives, concerns about hydrolytic degradation of the adhesive components have arisen. The purpose of this study was to evaluate the in-vitro influence of thermocycling, water storage and resin coating on the microshear bond strength of total etch and self etch adhesive systems to dentin.
The superficial coronal dentin of eighty intact third molars were exposed and divided into 5 equal groups. Dental adhesives including Scotch Bond Multi Purpose (SBMP), Single Bond (SB), Clearfil SE Bond (CSE), Prompt L-Pop (PLP), and Prompt L-Pop plus Margin bond (PLPM) were applied according to the manufacturers'' instructions on prepared surfaces in the study groups, respectively. Then composite cylinders were bonded and specimens were divided into two subgroups. One subgroup was stored in water for 24 hours. The second subgroup was subjected to 3000 thermocycle shocks and then was stored in 37°C water for 3 months. Finally, all teeth were subjected to the microshear bond strength test. Data were analyzed using two-way ANOVA and Tukey HSD tests. One specimen similar to each subgroup was also prepared for SEM evaluation.
After one-day storage, the SBMP showed the highest bond strength followed by CSE, PLPM, SB and PLP. After three months storage, the highest bond strength was observed in SBMP followed by PLPM, CSE, SB, and PLP.
SBMP showed the best bond strength while CSE represented acceptable bond durability. Resin coating on PLP improved bond strength and durability.

Children''s oral health related quality of life (OHRQoL) evaluates the impacts of oral daily activities of children and family on quality of life. Oral health related quality of life as outcome can be used to evaluate the dental health services. This study aimed to assess the extent to which dental treatment under general anesthesia affects quality of life of children and their families
One hundred parents of 3-10 year-old children who needed dental treatment under general anesthesia completed a parent-children perception questionnaire (P-CPQ) and family impact scale (FIS) before, and 4 weeks after dental treatment under general anesthesia. The questionnaire had statements related to oral health, functional limitation, emotional state and well being social well-being and family issues. Data were analyzed using SPSS version 11.5.
The mean scores and standard deviations of oral health quality of life of the children before and after dental treatment were 43.3 ± 7.14 and 39.24 ± 5.47 respectively. The mean scores of FIS before and after dental treatment were 8.00 ± 3.21 and 3.66 ± 2.62, respectively. The effect size of mean differences in P-CPQ and FIS scores were 1.84 ± 1.64 and 1.35 ± 4.34, respectively.
Provision of dental treatment under general anesthesia for uncooperative, young children with extensive dental problems had significant effects on quality of life of both children and their families.

Resin composites are common materials used to restore anterior teeth following root canal therapy, but are accompanied with shrinkage during polymerization. The aim of this in vitro study was to investigate the effect of the insertion method and polymerization shrinkage of resin composite on residual tooth structure.
Stereomicroscopy and computerized Finite Element Modelling (FEM) were used to compare residual stresses in endodontically treated, extracted maxillary central incisor teeth, in which the access cavities were restored with resin composite. Theoretical stresses derived from the FEM were analyzed during preparation and after teeth were restored using either a “bulk” or a “wedge incremental” method. These data were subsequently compared with stresses measured directly using strain gauges.
Results showed that intensive stresses, which had the potential to cause fracture in dental structures and composite de-bonding, were applied to teeth during polymerization.
According to the results of this study, the “bulk” build up led to less stress induction during restoration of teeth following root canal therapy.