ABSTRACT
Objectives: From the time composite has been developed, it has been subjected to various changes in composition like addition of filler and initiators to yield better result. One such modification is the new bulk fill composite. However an acceptable polymerization time to maintain adequate curing depth has to be evaluated. So the aim of this in vitro study was to evaluate the effect of polymerization time on curing depth of four bulk fill flowable composites. Methods: Total of 80 cylindrical specimens were prepared, and divided into 4 groups comprising of 20 specimens in each group. These selected groups were again subdivided into 4 groups comprising of 5 specimens in each group, based on their polymerisation time. The four specimens were Group A: SDR flow (DENTSPLY), Group B: Tetric N' Flow (Ivoclar Vivadent), Group C: Filtek bulk fill (3M) and Group D: Venus bulk fill (Heraeus Kulzer).The aluminium mold of 4mm depth and 5mm diameter was filled with composite and top surface was irradiated using Valo LED curing light with polymerisation time of 10, 20, 40, and 60seconds on respective subgroup.The microhardness of top and bottom surfaces were performed using Vickers Hardness tester under the load of 200gram for 15seconds. The depth of cure of each specimen was determined by hardness ratio method using the formula Hardness ratio=VK of bottom surface/VK of top surface.The results were statistically analysed. Results: The study results showed that all the tested bulkfill composites can be cured to an acceptable depth. Tetric N' Flow exhibits maximum curing depth (95.28 ±0.26) at 10sec polymerisation time. Venus bulk fill showed higher depth of cure at 20 and 40sec curing time (96.79±0.39 and 97.56±0.20). SDR flow showed adequate curing depth at 20 and 40sec curing time (92.94±0.49and 93.62±0.22 respectively). Filtek bulk fill has maximum depth of cure at 40sec curing (89.10±0.79). Conclusion: Increasing polymerisation time increases the top as well as bottom micro-hardness of all tested bulk fill composites. Tetric N' Flow maximum curing depth at 10sec curing time. Filtek bulk fill is the material with least depth of cure.
ABSTRACT
Background: Patients with dental anxiety are a heterogeneous group with origins, onset age and manifestations which vary to a great extent between individuals. Among the management options for dental anxiety, non-pharmacological management methods were found to be superior to anxiolytic drug therapies. Medications provide only short term cost effective solutions and an increased patient risk exists due to drug interaction or overdose. Present trend is towards non aversive techniques. Aim and Objectives: To compare the effectiveness of music distraction and brief relaxation method in anxious pediatric patients. Materials and methods: Ninety children of age group of 6-12years were selected randomly by simple random sampling and were divided into three groups with thirty children in each group grouped as - Group A: Control group, Group B: Patients treated with brief relaxation, Group C: Patients treated with music distraction. The patient's subjective anxiety recorded using modified version of the self-report Faces Scale by LeBaron et al. Study investigated using two physiological parameters i.e. heart rate and oxygen saturation, measured with pulse oximetery at different intervals. Results: The study result showed the brief relaxation better efficacy than music distraction in reducing anxiety as indicated by both the subjective and objective parameters except oxygen saturation which were used. But music distraction also helps in lowering the anxiety in children when music distraction group was compared with the control group. Conclusion: Our study found out that even though both brief relaxation and music distraction have the ability to reduce dental anxiety in children, brief relaxation showed more potential in reducing anxiety.