Desensitizing effects of an Er:YAG laser on hypersensitive dentine

The aim of the present study was to evaluate and compare the desensitizing effects of an Er:YAG laser (KEY II(R), KaVo, Germany) and Dentin Protector (Vivadent, Germany) on cervically exposed hypersensitive dentine.

A group of 30 patients showing a total of 104 contralateral pairs of hypersensitive and caries-free teeth was selected and randomly allocated in a split-mouth design to either (1) Er:YAG laser (80 mJ/pulse, 3 Hz), or (2) the application of Dentin Protector (polyurethane-isocyanate 22.5%; methylenechloride 77.5%) whereat one pair served as an untreated control in each patient. The degree of sensitivity to a thermal stimulus was determined qualitatively with an evaporative stimulus defined as a 3-s air blast at a distance of 2 mm from each site to be tested. A qualitative registration of the degree of discomfort was determined according to an arbitrary pain scale in 4 degrees. Recordings were assessed before treatment, immediately after, 1 week, 2 and 6 months after treatment by 1 blinded examiner.

Both treatment forms resulted in significant improvements of discomfort immediately after and 1 week post treatment. After 2 months, the discomfort in the Dentin Protector(R) group increased up to 65% of the baseline score and even up to 90% after 6 months, whereas the effect of the laser remained at the same level that was achieved immediately after treatment. The differences immediately after, 1 week, 2 and 6 months post treatment between both groups were statistically high significant (p< or =0.001; respectively). Compared to the untreated control group, both treatment forms resulted in a significant reduction of discomfort at each follow-up examination.

It was concluded that desensitizing of hypersensitive dentine with an Er:YAG laser is effective and the maintenance of the positive result was more prolonged than with Dentin Protector.