Surface smear layer was present on root surfaces of teeth that were root planed. Laser irradiation of 1 second at 3W completely removed the smear layer with minimal change in the diameter of the dentinal tubules. EDTA and citric acid were also effective in removing smear layer, but the exposed dentinal tubules showed funnel-shaped widening.

This study was conducted to evaluate the efficacy of desensitizing agents for the treatment of dentin hypersensitivity. Seventy-five hypersensitive teeth in 10 patients were studied. These were divided into five groups of 15 hypersensitive teeth: group I, control (triple distilled water); group II, 10% strontium chloride; group III, 5% potassium nitrate; group IV, 2% sodium fluoride; and group V, 40% formalin. The stimulus used to test thermal sensitivity was cold water at 15 degrees C, 10 degrees C, 5 degrees C, and 0 degrees C applied on every alternate day for 10 days. Results showed that 10% strontium chloride solution, 2% sodium fluoride solution, and 40% formalin solution significantly reduced dentin hypersensitivity, whereas a 5% solution of potassium nitrate did not.

An objective methodology was employed in the present in vitro study to assess bristle pressure required for plaque removal from the enamel surface of freshly extracted teeth. This bristle pressure has indirectly reflected the plaque tenacity or total attachment force of the plaque on the tooth surface. Equipment used to measure bristle pressure was especially fabricated for this purpose and described in detail with illustrations. The mean bristle pressure required for the removal of 1‐day, 2‐day, and 3‐day old plaque was 5.509 gms/cm2, 7.757 gms/cm2 and 14.28 gm/ cm2 which shows a ratio of 5:7:13 respectively, indicating an increase in plaque tenacity as it advances in age Further, the increase in tenacity of plaque from 2‐day to 3‐day was more as compared to the increase in tenacity from 1‐day to 2‐day plaque