Introduction:
Several dental procedures may lead to the development of dentine hypersensitivity. In patients undergoing prosthetic rehabilitation, hypersensitivity may be secondary to mechanical damage to hard tissues of the tooth as a result of grinding teeth to retain fixed dental restorations. Chemical methods are usually used to alleviate dentine sensitivity. Knowledge of the clinical efficacy of the available chemical preparations will enable the doctor to choose the most optimal desensitizing agent.

Aim of study:
To perform clinical evaluation of the therapeutic efficacy of selected chemical preparations: Duraphat and Seal & Protect varnish, Tooth Mousse paste and Green Or liquid in the treatment of dentinal hypersensitivity in patients using fixed prosthetic restorations.

Material and methods:
The size of the study group was 25 individuals with dentine hypersensitivity (100 teeth). Each patient who qualified for the study had four teeth with increased dentine sensitivity and underwent a single application of chemical preparations (each sensitive tooth was treated with a different chemical agent). The therapeutic efficacy of the preparations was assessed on the VAS scale by comparing the degree of pain intensity following mechanical and thermal stimuli at four occasions: directly after application of the preparations and during review appointments after 3 and 7 days, and 6 weeks.

Results:
Tooth Mousse paste brought instant relief to the patient directly after application (100% pain reduction in patients with low dentine sensitivity, and 85-90% with high sensitivity) and showed long-lasting effect (after 6 weeks, the therapeutic effect decreased by 1.5-10 percent compared to the results achieved directly after paste application). Slightly weaker (statistically insignificant) therapeutic effect was demonstrated by the Green Or preparation. The immediate relief after use in patients with low dentine sensitivity was obtained in 92.5%-98.5% of sensitive teeth. In the group with severe sensitivity, alleviation was achieved in 80-88% of cases. At review after 6 weeks, the clinical efficacy decreased by 7.5-10%. Fluoride varnishes (Duraphat and Seal & Protect) provided immediate relief after application in 68-75% of sensitive teeth in patients with low dentine sensitivity. When sensitivity was intense, the therapeutic effect was on the level of 25-36.4% of teeth not responding to the applied stimuli. The therapeutic effect after 6 weeks was maintained at 66.6-70% for teeth with low sensitivity and 45.5-56.6% for teeth with strong dentine sensitivity.

Conclusions:
The highest therapeutic efficacy in alleviating dentine sensitivity in patients using fixed prosthetic restorations was demonstrated by Tooth Mousse paste. Slightly weaker (not statistically significant) therapeutic efficacy was demonstrated by the Green Or preparation. The weakest effect at all stages of the study was noted for fluoride varnishes, which had a slower onset and weaker action than the combined preparations (statistically significant differences), and their therapeutic effect clearly decreased over time.