Caspian Journal of Dental Research

8-15

Authors: Faraneh Mokhtarpour, Homayoon Alaghehmand*, Soraya Khafri, Mina Mahdian

Introduction: Dental ceramics are considered as materials that can restore the appearance of natural teeth. Etching the inner surface of a ceramic restoration with hydrofluoric acid (HF) followed by using a silane coupling agent is a well-known and recommended method to increase the bond strength. The aim of etching on ceramic structure is to enhance the surface roughness (Ra) and energy and to cleanse the bonding area. The aim of this study was to evaluate the effect of different HF concentrations and etching times on the Ra of IPS e.max CADTM and Vita mark IITM. Material & Methods: Two HF concentrations (5% and 10%) and three etching times (20, 60 and 120 seconds) were evaluated. Etched patterns were observed by scanning electron microscopy (SEM) and Ra was measured using atomic force microscopy (AFM). Surface element analysis was performed using energy dispersive X-ray spectroscopy (EDAX). Data were analyzed on SPSS 20 using ANOVA and T-test. Results: The Ra had no significant difference among various Vita mark IITM specimens (P=0.973). Among IPS e.maxTM specimens etched with 5% HF, the AFM results showed that 20-s etching time had the lowest Ra and among those etched with 10% HF and 120-s etching time had the most Ra. In IPS e.maxTM specimens etched with acid for 20 s, a significant difference was observed in Ra of 5% and 10% acid concentrations (5% HF lower than 10% HF) (p=0.012). Conclusion: Among IPS e.maxTM specimens etched with 5% and 10% HF, increasing the etching time lead to higher Ra. For both IPS e.maxTM and Vita mark IITM, 20-s etching with 5% HF provides acceptable Ra for the bond.

25-31

Authors: Fatemeh Pachenari , Shima Nourmohammadi, Saber Babazadeh, Sara Maleki Kambakhsh*

Introduction: In direct aesthetic restoration, microleakage resulting from polymerization shrinkage of resin composites is still challenging. Different strategies such as maximizing the amount of inorganic filler with prepolymerized filler and different silorane matrixes have introduced to overcome this issue. The aim of this experimental study was to compare the microleakage in low-shrinkage methacrylate-based (Clear fil AP-X) and silorane-based (Filtek P90) composite resins in class II cavities on primary molar teeth. Materials & Methods: Classic class II slot cavity preparation was done on 60 healthy human primary molars. Specimens were randomly divided into two groups. For restoring the cavity in group I: methacrylate-based composite resin, and in group II: silorane-based micro-hybrid composite resin were used. The samples were thermocycled and soaked in 2% basic fuchsine dye for 24 h. They were longitudinally sectioned and observed at the gingival margins under ×10 magnification. Scores were assigned upon the amount of dye penetration. The Mann-Whitney U-test through SPSS19.0 was used for statistical analysis of data. Results: In both groups, the major of samples showed score 0 of dye penetration. The comparison of gingival margin leakage indicated no significant difference between two groups. Conclusion: Both restorative materials, irrespective of their type had microleakage. Given the comparable microleakage of silorane-based (Filtek P90) and low-shrinkage methacrylate-based (Clear fil AP-X) composite resins in Class II cavities of primary molars, the clinical efficacy of both materials seems to be similar.

42-48

Authors: Maryam Hosseini , Mohammad Mehdi Naghibi Sistani, Soraya Khafri, Mahtab Hamzeh*

Introduction: Since the first permanent molar (FPM) as a first permanent tooth erupts between 6-7 years old and has a long period of eruption, it is the most caries prone tooth. One of the problems is inadequate knowledge of parents about the eruption time of the FPM; because these teeth erupt behind the deciduous teeth without a primary successor. In the present study, mothers' knowledge about its eruption time and its effect on health of these teeth was evaluated. Materials& Methods: This cross-sectional study was conducted on 406 schoolchildren (7-9 years old) and their mothers using multi-stage sampling in Babol in 2017. Mothers completed the check list according to the study objectives. Clinical status of FPM was measured using DMFT (Decayed, Missed, Filled Teeth) index. Finally, data were analyzed with SPSS 18 using t-test and chi-square. Significance level was considered as p<0.05. Results: Mothers’ awareness about the eruption time of FPM (p<0.001) was associated with higher ratio of children with sound FPM. Mothers’ education level was the most significant contributing factor to mothers' knowledge about FPM eruption time. Conclusion: Mothers’ education and their knowledge about the FPMs eruption time were the major predictors of FPM caries status.

56-62

Authors: Imaneh Asgari*, Asma Amiri

Introduction: Although though the best way to assess individual’s oral hygiene is to measure plaque and calculus indices, various studies have evaluated an individual’s self-report of oral-hygiene behaviors. The aim of this study was to investigate diagnostic values of self-reporting tool and relationship between current oral self-care behaviors and plaque index (PI). Materials & Methods: This cross-sectional study was conducted on 260 13-15-year-old students from girls’ schools in Isfahan using two-stage randomized sampling. Data collection tools on oral-hygiene habits were extracted based on available studies and presented in two versions for student and parent. Then, students’ PI was measured by a trained and calibrated examiner using Silness and Loe PI. The frequency of oral-hygiene behaviors reported by parents and students with PI was measured by McNemar, Kappa and Mann Whitney tests with significance level of 0.05. Sensitivity and specificity of the tools were calculated based on the standard PI. Results: The PI mean (SD) was 1.07 ±0.5. There was a significant relationship between PI and self-reported toothbrushing status (p=0.017). The PI was higher in students with bad toothbrushing habits based on the reports of themselves and their parents as well as with bad flossing habits based on their parents’ reports (p= 0.017, 0.001, 0.005). Diagnostic value of children’s self-report and parental report about toothbrushing status indicated low sensitivity (about 35%) and high specificity (about 83%). Positive predictive value was approximately good (about 71%) and negative predictive value was low (about 52%). Diagnostic value of parental report about flossing status represented high sensitivity (85%) and low specificity (26%). Conclusion: Findings of this study suggested that among such population, students with bad toothbrushing habits based on parental and self-reports are more likely to have undesirable (moderate/poor)PI.