Neeraj Malhotra

Effect of three indigenous food stains on resin-based, microhybrid-, and nanocomposites.

PURPOSE This study investigated the effects of three indigenous food stains (tea, tobacco, turmeric) on a nanocomposite (Ceram-X-Mono, Dentsply DeTery, Konstanz, Germany), a microhybrid posterior (P60, 3M ESPE, St. Paul, MN, USA), and a universal microhybrid (Z100, 3M ESPE) resin-based composite (RBC). MATERIALS AND METHODS Thirty-six disk-shaped specimens were fabricated (10 × 2 mm) for each type of RBC material, using a polytetraflouroethylene (PTFE) sheet. Specimens from each group were randomly distributed into three subgroups for each of the used stains. The baseline color values were measured using a spectrophotometer. The specimens were immersed in the staining solutions for a period of 3 hours per day for 15 days (3 hours/day × 15 days). Following this, the color change value (ΔE) was calculated. RESULTS AND CONCLUSION All the tested groups showed a clinically perceptible color change (ΔE values = 3.3 or >3.3), except for tea-stained P60 (ΔE = 3.15) and Z100 (ΔE = 1.63) groups. Turmeric caused the most significant color change for all the tested RBCs. The least amount of color change was observed with the Z100 (tea, ΔE = 1.63; tobacco, ΔE = 13.59; turmeric, ΔE = 38.77) group that was statistically significant from P60 (tea, ΔE = 3.15; tobacco, ΔE = 18.83; turmeric, ΔE = 57.72), and Ceram-X-Mono (tea, ΔE = 3.32; tobacco, ΔE = 18.83; turmeric, ΔE = 53.95) groups.

An in vitro evaluation of shear bond strength of silorane and bis-GMA resin-based composite using different curing units

Aim: To evaluate shear bond strength of silorane and bis-GMA based composite resins using self-etch and total-etch adhesive systems, and compare the effect of Quartz-tungten-halogen (QTH) and Light emitting diode (LED) on the shear bond strength of the experimental materials. Materials and Methods: Flat dentin surfaces were exposed on intact extracted molars and composite resin was built 2 mm in diameter. Teeth were divided randomly into four groups. Groups 1 and 2 were restored with P90 system adhesive and Filtek P90 and cured with QTH and LED units respectively. Groups 3 and 4 were restored with total etch adhesive and Filtek Z100 and cured with QTH and LED units respectively. Specimens were subjected to shear bond strength testing using Instrom Universal testing machine. Results: Data was subjected to one-way analysis of variance. Total-etch groups gave significantly higher shear bond strength values than the self-etch groups. No significant difference in shear bond strength was found between Groups 3 and 4, while Group 1 showed significantly higher values than Group 2. Conclusion: Type of light curing unit is not a significant factor affecting shear bond strength for bis-GMA RBCs using total-etch technique; while for curing silorane resin based composite (RBCs), conventional halogen curing units showed better results.

Current Strategies and Applications of Tissue Engineering in Dentistry − A Review Part 1

UNLABELLED A new direction in the field of vital pulp therapy is given by the introduction of tissue engineering as an emerging science. It aims to regenerate a functional tooth-tissue structure by the interplay of three basic key elements: stem cells, morphogens and scaffolds. It is a multidisciplinary approach that combines the principles of biology, medicine, and engineering to repair and/or regenerate a damaged tissue and/or organ. This two part article reviews and discusses the basic concept and strategies so far studied and researched for the engineering of basic dental tissues, to restore a functional tooth anatomy. This first part focuses on a detailed description of key elements used in tissue engineering and their applied clinical applications in dentistry. The second part will deal with the strategies that are being used and/or developed to regenerate the tooth tissues with the help of this scientific principle. CLINICAL RELEVANCE The field of tissue engineering has recently shown promising results and a good prospect in dentistry for the development of the most ideal restorations to replace the lost tooth structure with a functional replacement.