Methods: After obtaining ethical approval, a randomized clinical trial was conducted on visually impaired adults in two social and training centres for the blind. At baseline, the study subjects were interviewed and clinically examined by calibrated examiners using a LED intra-oral light, disposable mirrors, and periodontal probes. The oral hygiene and gingival health status of index teeth were recorded using the Visible Plaque Index (VPI) and the Gingival Bleeding Index (GBI), respectively. They were then randomly allocated into the conventional OHI or the customized OHI group. Instructions on toothbrushing and interdental cleaning were provided. An evaluation clinical examination was conducted 2 weeks later.
Results: Forty-two subjects were recruited at baseline and 38 (90.5%) were examined in the evaluation. The mean VPI score of the subjects in the conventional OHI group reduced from 0.238 at the baseline to 0.120 at the evaluation examination (paired t-test, p=0.001). The mean VPI score of the subjects in the customized OHI group reduced from 0.249 at the baseline to 0.107 at the evaluation examination (paired t-test, p<0.001). The amount of reduction in the mean VPI score between the two OHI groups, 0.114 and 0.118, is not statistically significant (two-sample t-test, p>0.05). Similar magnitudes of reduction in GBI scores were also found in the two OHI groups (0.060 vs. 0.058; two-sample t-test, p>0.05).
Conclusions: Provision of either conventional OHI or customized OHI to the visually impaired adults in Hong Kong can improve their oral hygiene and gingival health status. There are no significant differences between the short-term effectiveness of providing the above two types of OHI.