Reiko Suda

The Effect of Adding Calcium Lactate to Xylitol Chewing Gum on Remineralization of Enamel Lesions

The purpose of the study was to determine whether adding calcium lactate to chewing gum containing xylitol enhances remineralization of enamel surfaces using an early caries lesion model. Enamel slabs were cut from human extracted sound teeth and artificial subsurface lesions created within each. Half the enamel slabs were used as controls and stored in a humidifier while half were mounted into oral appliances worn by 10 volunteers (22–27 years old, 2 males and 8 females) in a three-leg trial, during which they wore the appliance without chewing gum, chewed gum containing xylitol + calcium lactate or chewed gum containing only xylitol 4 times a day for 2 weeks. Calcium concentrations in the enamel surfaces of control and test slabs were measured by X-ray spectrometry and degrees of remineralization were calculated. The mean degree of remineralization was greater after chewing xylitol-Ca gum (0.46 ± 0.10) than after no gum (0.16 ± 0.14) or after chewing xylitol gum (0.33 ± 0.10) (p < 0.01). In conclusion, chewing gum containing xylitol + calcium lactate could enhance remineralization of enamel surface compared to chewing gum containing only xylitol or no gum chewing.

A 4-year prospective study of the progression of periodontal disease in a rural Chinese population.

OBJECTIVES The natural progression of periodontitis in the Chinese population is not well researched. We investigated the progression of periodontal disease over 4 years in 15-44-year-old Chinese villagers with no access to regular dental care. METHODS In 1992, 486 villagers were enrolled, and in 1996, 413 villagers were re-examined. Probing depth (PD) and clinical attachment level (CAL) were examined at six sites per tooth. Sites with ΔCAL ≥3 mm were defined as active sites. Cross-sectional and longitudinal analyses were performed using means and percentile plots. RESULTS The mean CAL increased by 0.26 mm over 4 years. The incidence of periodontitis (at least one site with CAL ≥3 mm) was 8%. The incidence of periodontitis among those with no periodontal disease at baseline was 44.9%. Seventy-eight percent of the subjects had at least one active site. In the 15-24-year group, 244 of 401 active sites had gingival recession, while only 51 active sites had both gingival recession and deeper pockets. In the 25-34-year and 35-44-year groups, almost one-third of the active sites (329/1087) and more than one-third of the active sites (580/1312) respectively had a combination of gingival recession and deeper pockets. CONCLUSIONS In this study, we demonstrated that in Chinese population without regular dental care, both the initiation of periodontitis and progression of previously existed periodontitis contributed to the natural progression of periodontitis and periodontal pocketing played a greater role with age increasing. CLINICAL SIGNIFICANCE This rare study reports the natural progression of periodontal disease in a group of Chinese villagers (15-44 years) with virtually no access to regular dental care.

Statin decreases IL-1 and LPS-induced inflammatory cytokines production in oral epithelial cells

Periodontitis is a choronic inflammatory disease associated with degradation of periodontal tissues. This disease is considered to result of production of proinflammatory cytokines and tissue degradative enzymes which are initiated and advanced by lipopolysaccharide (LPS) of oral bacteria.

Evaluation of the Effectiveness of Screening for Periodontal Disease by Questionnaire.

アンケート調査によって調べた自覚症状と臨床所見との関連性を分析し, アンケート調査による歯周病のスクリーニングの有効性について統計学的検討を行った。中国承徳市近郊の歯科医療低普及地域の住民486人 (14～44歳, 男性211名, 女性275名) について調査を行った。歯肉出血 (GI), ポケット (PD), アタッチメントレベル (AL) などの臨床診査, パノラマX線写真撮影及び, 歯肉出血, 歯の動揺など歯周病に関連すると思われる自覚症状18項目について聞き取り調査を行った。その結果, 個人別に見ると, 最低0, 最高16項目, 平均約5項目の自覚症状を有していた。自覚症状の数と年齢, および臨床診査における各個人別平均値との間に有意な相関が認められた。なかでも, ALとの相関が高くr=0.52), GIとの相関が最も低かった (r=0.17) 。CPITNを基準としてスクリーニングを試みた結果, 自覚症 (状の数が6項目以上の者を重症とした場合, 感度0.68, 特異度0.67であった。さらに, ALと関連のある項目を選択することで, より良好な感度が得られた。