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EVALUATION OF MICRO-LEAKAGE OF INDIRECT RESIN COMPOSITE INLAY CEMENTED TO DENTIN WITH DIFFERENT RESIN CEMENT STRATEGIES احمد محمود رباح
Objective: To evaluate micro-leakage of indirect resin composite inlay lutedto dentin after specimen's storage in distilled water and lactic acid. ...
Evaluation of Micro-Tensile Bond Strength of Indirect Resin Composite Inlay to Dentin احمد محمود رباح

Objective: To evaluate micro-tensile bond strength (μTBS) of indirect resin composite inlay to dentin after specimen's storage in distilled water and lactic acid.

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Effect of self etching ceramic primer and universal adhesive on bond strength of lithium disilicate ceramic. Journal of Adhesion Science and Technology (2017) Mohamed Moustafa Awad
The clinical success of ceramic restorations is affected by the ceramic bonding procedure.  ...
Comparative evaluation of nickel discharge from brackets in artificial saliva at different time intervals Dr Narendra Varma Penumatsa

Objectives: To determine and compare the potential difference of nickel release from three different orthodontic brackets, in different artificial pH, in different time intervals. Materials and Methods: Twenty‐seven samples of three different orthodontic brackets were selected and grouped as 1, 2, and 3. Each group was divided into three subgroups depending on the type of orthodontic brackets, salivary pH and the time interval. The Nickel release from each subgroup were analyzed by using inductively coupled plasma‐Atomic Emission Spectrophotometer (Perkin Elmer, Optima 2100 DV, USA) model. Quantitative analysis of nickel was performed three times, and the mean value was used as result. ANOVA (F‐test) was used to test the significant difference among the groups at 0.05 level of significance (P < 0.05). The descriptive method of statistics was used to calculate the mean, standard deviation, minimum and maximum. SPSS 18 software ((SPSS.Ltd, Quarry bay, Hong Kong, PASW‐statistics 18) was used to analyze the study. Result: The analysis shows a significant difference between three groups. The study shows that the nickel releases from the recycled stainless steel brackets have the highest at all 4.2 pH except in 120 h. Conclusion: The study result shows that the nickel release from the recycled stainless steel brackets is highest. Metal slot ceramic bracket release significantly less nickel. So, recycled stainless steel brackets should not be used for nickel allergic patients. Metal slot ceramic brackets are advisable. 

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Correlation of lip prints and lip competence in children Dr Narendra Varma Penumatsa

Introduction: Individual identification is a significant and difficult task in forensic search; it was based on logical values. A lip print is different in every living individual and does not change with time so it can be used as a tool in forensic investigations. The present work aimed to find out the correlation between lip prints and lip competence in the pediatric population of Davangere city. Materials and Methods: The study sample comprised of 103 children that is, 49 males and 54 females of aged between 4 and 14 years. The lip impression was made on a strip of cellophane tape on adhesive portion; it was then placed to a white bond paper. This serves as permanent record. In this study, we are followed the classification of patterns of the lines on the lips proposed by Tsuchihashi. For recording lip competence, we considered Ballard criteria. Results: Chi‐square test was used to find out the degree of association between variables and to check out whether statistically significant differences exist. Conclusion: Lip prints are unique for every person and show differences according to the race and the ethnic origins of a person. The present study confirmed the distinctiveness of cheiloscopy but disproves any statistical correlation of lip print with lip competency. 

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Evaluation of remineralization capacity of casein phosphopeptide-amorphous calcium phosphate on the carbamide peroxide treated enamel Dr Narendra Varma Penumatsa

ABSTRACT

Objective: The aim of this study was to evaluate the potential of casein phosphopeptide‐amorphous calcium phosphate (CPP‐ACP) in remineralizing the bleached enamel surface using micro‐hardness. Materials and Methods: Thirty human enamel slabs were randomly divided into three groups (n = 10). Groups A and B were exposed to 20% carbamide peroxide and 35% carbamide peroxide gel, respectively. After the exposure to the bleaching agent, the slabs were kept in artificial saliva for 1‐week. Group C (control group) were kept in artificial saliva for 1‐week. Vickers micro‐hardness test was performed by Leica VMHT‐Mot micro‐hardness tester. CPP‐ACP (Gc Tooth Mousse, Melbourne, Australia) was then applied to specimens of Groups A and B for 3 min for 2 weeks. Micro‐hardness values of postbleach Group A (Ar) and Group B (Br) were recorded and statistically analyzed by paired t‐test and one‐way analysis of variance at the significance level of α =0.05. Results: There was a significant decrease in micro‐hardness of enamel in carbamide peroxide bleached groups. However, there was a significant increase in micro‐hardness after the remineralization by CPP‐ACP and the extent of remineralization is more for the Group B. Conclusions: That bleaching agents reduced enamel micro‐hardness and the use of CPP‐ACP after bleaching can significantly enhance the micro‐hardness of bleached enamel. 

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The influence of finishing/polishing time and cooling system on surface roughness and microhardness of two different types of composite resin restorations Dr Narendra Varma Penumatsa

Objective: The aim of this study was to evaluate the effect of finishing time and polishing time on surface roughness and microhardness of nanofilled and hybrid resin composites. Materials and Methods: Hundred disk composite specimens from micro hybrid composite and nanohybrid composite were prepared, 50 for each type of composite. The specimens were divided into five groups according to the time of finishing and polishing (immediate, 15 min, 24 h and dry). Composite under the Mylar strip without finishing and polishing was taken as the control group. Surface roughness was measured with environmental scanning electronic microscope (ESEM) and microhardness was determined using Vickers Microhardness Tester. Data collected were statistically analyzed by t-test and one-way analysis of variance (ANOVA) followed by Turkey’s post hoc test. Results: Smooth surface with low hardness was obtained for the group under Mylar strip without finishing and polishing. The highest roughness was recorded for delayed finishing and polishing for both composites. Immediate finishing and polishing increased the surface hardness more than that in the control group in both types of composites. Dry finishing reduced the hardness significantly for micro hybrid composite, but resulted in the highest surface hardness for nanofilled composite. Conclusion: Immediate finishing and polishing under coolant resulted in the best surface smoothness and hardness values in micro hybrid composite; however, immediate dry finishing and polishing gave the best smoothness and hardness values in nanohybrid composite. 

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COMPARISION OF MICROLEAKAGE BETWEEN GLASS IONOMER AND FLOWABLE COMPOSITE RESIN RESTORATIONS –– AN IN-VITRO STUDY Dr Narendra Varma Penumatsa

Aim: The aim of the present study was made to evaluate the micro leakage of a Glass ionomer (FUJI VII) and micro hybrid flowable composite resin (Tetric flow) in enamel of both deciduous and permanent teeth.

Methodology: The study has been done on total of 32 teeth in which 16 permanent teeth were orthodontically extracted and 16 over retained deciduous teeth were extracted. Teeth were randomly divided into four groups of 8 teeth in each group. Standard class I cavities of 1.5 mm depth and 1 mm depth were made on occlusal surfaces of all the teeth. The samples were divided into four groups of which 8 deciduous teeth are for Fuji VII and 8 deciduous teeth for Tetric flow composite and 8 permanent teeth for Fuji VII and 8 permanent teeth for Tetric flow composite. Samples were immersed into 5% Methylene blue dye for 24 hours after restoration with the respective materials. The teeth were sectioned vertically into two halves and observed under the reflected light microscope under 50 x magnifications to observe the level of dye penetration.

Results: while computing the “T” test between the deciduous and permanent teeth for Tetric flow and Fuji VII it was found that there exists no significant difference in the micro leakage. But surprisingly it was found that micro leakage of Tetric flow was least in the permanent group.

Conclusion: There is no much significant difference in the micro leakage was observed among all groups. 

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Bleaching of fluorosis stains using sodium hypochlorite Dr Narendra Varma Penumatsa

Fluorosis staining is commonly considered an esthetic problem because of the psychological impact of unesthetic maxillary anterior teeth. Numerous treatment approaches have been proposed, ranging from bleaching to enamel reduction to restorative techniques. Bleaching of hypomineralized enamel lesions, using 5% sodium hypochlorite, has been useful clinically. The technique described, in this case, appears to have advantages over other methods for improving the appearance of fluorotic lesions. It is simple, low cost, noninvasive, so the enamel keeps its structure, relatively rapid, and safe; it requires no special materials, and it can be used with safety on young permanent teeth. 

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my publications Dr Mohammed zaheer kola
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