Abstract
Smoking is a major risk factor for a variety of oral diseases. In particular, smoking-induced dental stains have been shown to be more refractory than those in non-smokers. Hydroxyapatite (HAP) is a biomimetic material that has been shown to be helpful in many oral health applications; however, its efficacy in stain removal in smokers and non-smokers is uncertain. To compare the effects of HAP toothpaste on the removal/control of extrinsic tooth discoloration in smokers and non-smokers. The secondary goal was to compare smokers and non-smokers in terms of staining extent and response to HAP. A total of 100 adults (50 smokers, 50 non-smokers) who met the inclusion and exclusion criteria were invited to participate in the study. At baseline and 2 weeks after the intervention, the same examiner performed clinical observations, including measurements of anterior tooth stain using the approximal plaque index (API) and the Lobene stain index. Adverse events and any changes in general health conditions of the patients were monitored. Comparisons of indices at baseline and post-intervention yielded statistically significant differences. In non-smokers, the median API (IQR) at baseline was 32.5 (19.0, 63.0) which decreased to 16.5 (7.0, 42.0) after the intervention (p < 0.001). The median Lobene stain index (extension) at baseline and after the intervention was 0.9 (0.5, 1.3) and 0.3 (0.2, 0.7), respectively (p < 0.001). In smokers, the median API at baseline (IQR) was 46.0 (30.0, 86.0), which decreased to 23.0 (7.0, 43.0) (p < 0.001) post-intervention. Lobene stain indices were lower after intervention in all groups than at baseline (all, p < 0.001), and the magnitude of reduction was more prominent in the smoker group. This study demonstrates that 2-week use of a toothpaste containing HAP can effectively reduce extrinsic tooth stains in smokers and non-smokers.