Abstract
Dentinal hypersensitivity has been studied for several years. It is reported as a strikingly painful condition that originates from the exposure of dentinal tubuli when the thickness of the enamel or cement is significantly reduced. Usually the exposed area is subjected to several kinds of stimuli, resulting in sharp acute pain. The aim of this study was to evaluate the efficacy of low level laser therapy (LLLT) in the treatment of patients with dentinal hypersensitivity. A total of 1102 teeth of 388 patients were treated with LLLT between 1995-2000. Ninety-eight males and 290 females aged 30 to 45 years old were treated. For LLLT, a 780nm continuous wave diode laser was used at an output of 40mW, elliptical area of the beam, 2mm2, and exposure time per point of 25s. This corresponds to an equivalent dose of 50 J/cm2 at each point (considering the area of the spot). If a 1 cm2 area is considered, the total dose per tooth was 4J/cm2. With the 830nm CW 50mW diode laser, the elliptical area of the beam was 2mm2, and exposure time per point was 20s. This corresponds to an equivalent dose of 50J/cm2 at each point (considering the area of the spot). If a 1cm2 area is considered, the total dose per tooth was 4J/cm2. The results showed 403 (36.57%) out of 1102 teeth required a single session for complete remission of the symptom, 255 (23.14%) needed two sessions; 182 (16.51 %) three sessions; 107 (9.7%) four sessions; and 59 (5.35%) five sessions. Ninety-six (8.71%) did not respond to LLLT and the patients were re-assessed and treatment changed. The more affected tooth was the lower premolar (301 - 27.4%), followed by lower molars (163 - 14.8%), upper premolar (149 - 13.5%), lower incisive (148 - 13.4%), upper canine (119 - 10.7%), upper incisive (108 - 9.9%), lower canine (62 - 5.6%), and upper molars (52 - 4.7%). The result of the present investigation demonstrates that LLLT, when used with the correct irradiation parameters, is effective in treating dentinal hypersensitivity, as it quickly reduces pain and maintains a prolonged pain-free status in 91.27% of the cases. Previous studies carried out by the authors examined the histological reaction of the dentinal pulp in rats after application of LLLT. The LLLT was shown to be effective in stimulating odontoblasts, producing repaired dentine and closing dentine tubuli.
