The study samples were 1015 participants at a senior citizen educational program, whose mean age was 67.1 years. Oral health related quality of life was measured using the short version of Oral Health Impact Profile (OHIP-14, Slade, 1997), which included questions about functional limitations, physical pain, psychological discomfort and disability, physical disability, social disability, and handicaps. The OHIP-14 scores were calculated by counting of the number of items to which a subject responded "fairly often" or "very often" (OHIP-14 SC). Therefore higher OHIP-14 score means lower oral health related quality of life.
The prevalence of reported impacts was the highest in "Uncomfortable to eat (8.1%)", followed by "Self-conscious (5.2%)." On the whole, the prevalence of impacted subjects was higher in sub-domains of physical pain and psychological discomfort, however it was lower in social disability and handicaps, which was similar to the previous reports from Australia, USA, and Canada.
The OHIP-14 SC was significantly associated with self-assessed general health (P<0.001), financial status(P<0.01), educational level (P<0.05), dental status (P<0.001) and perceived need for dental treatment (P<0.001),however, was not associated with age, gender, and domicile.
The OHIP-14 SC of Japan was higher than rural Australia, USA white people and rural Canada, while it was lower than USA black people or Hong Kong. The difference in OHJP-14 SC among countries may be explained in a number of ways. They may be due to differences in the conceptual and linguistic equivalence of translated items(delicate shades of meaning of the question), or to differences in the social security system, the health insurance system, or national character (optimistic or pessimistic), or to the true differences in the perceived severity of oral health across cultures. A study of a more representative sample will be needed to determine the applicability of these findings on the Japanese population.