Assessment of microleakage of three restorative materials in class V cavities. an in vitro study

To evaluate the marginal microleakage in class V cavities restored with three different restorative materials using dye penetration scoring system. Cross sectional study. This study was conducted at Dental Clinic laboratory, Juma building research laboratory, and Multidisciplinary laboratory, The Aga Khan University, Karachi for a period of six months from April 2008 to September 2008. One hundered and fifty extracted premolars were randomly selected. Standardized class V cavities were prepared and then divided into three equal groups: Group I was restored with composite resin, Group II with glass ionomer cement and group III with resin modified glass ionomers. They were then subjected to thermocycling, immersed in 2% methylene blue dye, sectioned and examined under dissection microscope. Dye penetration for each section was recorded and data was analyzed. Lowest leakage was found in Group I [composite resin] and maximum in Group II [conventional glass ionomer]. Microleakage at gingival margins was significantly more than that at occlusal margins in all groups. Composite resins and resin modified glass ionomers provide a better seal than glass ionomers in class V cavities. All materials show more microleakage at gingival margins as compared to occlusal margins

Comparison of convergence angle of prepared teeth for full veneer metal ceramic crowns

To compare clinically practiced convergence angle values of tooth preparation with recommended values, and also the effect of tooth position and operator experience on convergence angle. Analytical study. The study was carried out at the Dental clinic, The Aga Khan University Hospital, Karachi, from January to June 2007. A minimum of 75 crown preparation dies including 25 dies in each group of teeth [anterior, premolars and molars] were collected retrospectively which were prepared by residents and specialists of operative dentistry. AutoCAD 2007 software was used for measurement of convergence angle. One sample t-test was applied to compare the mean practiced convergence angle values with its recommended values. Two way ANOVA was applied to measure difference in convergence angle values with respect to operator experience and tooth type with the level of significance being a=0.050. Mean reported convergence angle value was 22.72°, which was significantly greater [p < 0.001] than the recommended values. Statistically significant difference in convergence angle was found between anterior vs. molar teeth and between premolars vs. molar teeth [p=0.0001 and p=0.002, respectively]. There was a considerable disparity between the convergent angles values recorded in this study and the recommended guidelines. Measured convergence angle values were greater for posterior teeth as compared to the anterior teeth

Assessing the perception of smile attractiveness in young adults, a pilot study

To assess the perception of dental, art and business students on the importance of smile attractiveness and the understanding on effect of skin tone on tooth shade value as perceived by the 3 groups. It was a cross sectional, analytical study conducted in Art, Business and Dental Schools. Ninety 90 students [3 groups of 30 each]were selected by non probability, purposive sampling. 24 pictures were run in front of the participants as power point presentations. The pictures were of two individual smiles, a male and a female, with changes made to colour of teeth and skin, in Adobe Photoshop. The participants were asked to grade each picture on a rating scale. SPSS 17.0 was used for data analysis. Frequency distribution of all variables was determined. Association of smile attractiveness with gender and profession was determined using Chi-square test. Mean ranks and score [of the 24 pictures] of smile attractiveness as perceived by the 3 groups were compared using Kruskall-Wallis test. Level of significance was set at 0.05. The sample size consisted of 34.1%males and 64.8%females. For the dental group smile attractiveness was very important as opposed to the business and art students. For females, smile attractiveness was more important than their male counterparts. Fair skin with bright and moderately bright teeth rated as the most attractive smile, whereas fair skin with dark teeth rated as the least attractive smile. There is a difference in perception of smile attractiveness between males and females. Art, business and dental students also have different perceptions of smile attractiveness with respect to skin tones and tooth shade values

Teaching and practice of repair of resin composite restorations in dental institutions of Karachi

1.To determine the proportion of dental institutions' faculty teaching repair of composite restorations to dental students [undergraduate]. 2.To evaluate the factors that affect the decision making process of Resin Composite restoration repair. An 11 item questionnaire was presented to the faculty members of all the dental institutions in Karachi. Nine out of ten dental institutions participated in the survey and a total of 38 faculty members from the department of Operative Dentistry filled the questionnaire. About 90% of the respondents stated that composite repair is advisable whereas 70% of the respondents stated that they have performed such type of interventions and have achieved success. Around 40% stated that they teach such procedures to students and60%stated that the course of instruction is at clinical level. 1.The findings of the present study indicate that the teaching of the repair of defective composites has found a place in primary dental degree curricula in almost all the dental institutions in the Karachi. 2.Occlusal relationship and patient's existing oral hygiene appeared to be the most important factors in decision making process

Frequency and distribution of endodontically treated teeth

To determine the distribution and pattern of carious teeth involvement in permanent teeth requiring endodontic treatment. Cross-sectional study. Dental Section of The Aga Khan University Hospital, Karachi, from September 2004 to March 2005. Data was collected from the dental records of patients. Tooth was the unit of evaluation. Variables studied were demographics, tooth type, etiology of endodontic treatment and pattern of caries involvement. Data was analyzed using chi-square test and Fischer's exact test. The total number of patients was 190; total number of teeth involved were 235. Females had more endodontically treated teeth than males. There was no significant difference in the distribution of etiology of endodontic treatment in both genders [p=0.564]. An increasing trend of endodontic procedure was observed with the increasing age of patients. Caries was the most common etiological factor leading to endodontic treatment [p = 0.011]. Class-II cavity i.e. proximal surface of teeth was the most commonly involved surface in endodontically involved teeth [p < 0.001]. More molars had been endodontically treated followed by premolars and anterior teeth. Caries was the most common etiologic factor; lower molars were the most commonly involved and lower anteriors the least commonly involved teeth in endodontic procedure. Significant association was observed between etiology and tooth type. Significant association was found between cavity classification and etiology of endodontic treatment with class-II caries being most common

Factors associated with non-carious cervical lesions [NCCLs] in teeth

To determine factors associated with Non-Carious Cervical Lesions [NCCLs] and the teeth most commonly involved in such lesions. Cross- sectional study. Department of Operative Dentistry, Section of Dentistry at Aga Khan University Hospital, Karachi, Pakistan, from December 2005 to January 2006. A total number of 95 patients with 671 teeth were evaluated using a pre-coded questionnaire. Subject of evaluation was teeth. Patients with symptomatic or asymptomatic NCCLs and permanent dentition were included. Patients exhibiting active, untreatable periodontal disease, rampant uncontrolled caries, xerostomia, primary dentition, patients undergoing orthodontic treatment or bleaching procedure were excluded from the study. Data analysis was done using Spearman's correlation, Mann Whitney test and Kruskal-Wallis test. Mean age of patients was 50.3 years [r=0.22, p=0.028]; males [73%] had more NCCLs than females [23%]. Majority [45.3%] of them brushed their teeth twice a day, with medium type of brush [48.4%] and horizontal [73.7%] brushing technique. Most of the patients were non-bruxists [90.5%], with Angles Class 1 occlusion [48.4%] and canine guidance [50.5%]. Majority [74.7%] of the patients did not have sensitivity. First premolars in all the quadrants were the most frequently involved teeth in NCCLs. More males had NCCLs. Middle aged patients were more involved. A weak positive correlation was found between age and NCCLs. No association was observed between hand used and site of NCCLs, between wear facets and NCCL, Excursive guidance and NCCL, Angles classification and NCCL