P9 Screening for severe periodontal disease in an elderly population using methyl mercaptan concentration ratio

Abstract

Objective The purpose of this study was to examine the usefulness of methyl mercaptan concentration ratio on mass screening for periodontal disease in an elderly population.Methods One hundred and twenty‐two individuals (73 males and 49 females) aged 75 years who had at least 20 teeth in 2003 were chosen from participants of the Niigata Elderly Study (longitudinal study since 1998). Volatile sulfur compounds (VSC) in their mouth such as hydrogen sulfide (H2S), methyl mercaptan (CH3SH) and dimethyl sulfide ((CH3)2S) were measured, using portable gas chromatography (Oral Chroma®, Abilit Co Ltd, Osaka, Japan). The subjects were divided into periodontitis/no periodontitis groups based on having at least one site of pocket depth with more than 6 mm (PD 6+ mm). A CH3SH concentration ratio was defined as CH3SH/(CH3SH + H2S). The receiver operating characteristic curve was plotted to decide the best cut off point of the CH3SH concentration ratio for screening of subjects with PD 6+ mm.Results and discussion The best cut‐off point of the CH3SH concentration ratio was 0.35, and the sensitivity and specificity of this cut‐off point were 58.7 and 68.4%, respectively. The percentage of subjects with PD 6+ mm in the group of CH3SH concentration ratio ≥0.35 was 52.9 % (27 of 51) and that in the <0.35 group was 26.8 % (19/71), and, the groups were significantly different (P = 0.0059, χ2 test). It had been reported that VSC, in particular CH3SH concentration, was significantly higher in persons with periodontal disease than in periodontally healthy persons. Furthermore, in this study, the use of a portable gas chromatography enabled the VSC measurements for periodontal disease screening outside of the clinic.Conclusion These findings suggest that CH3SH concentration ratio may be useful on mass screening for periodontal disease in an elderly population.