MORI Yuko Osaka University Dental Hospital, Instructor, 歯学部・附属病院, 医員
KISHIMA Tetsuhiko Osaka University Dental Hospital, Instructor, 歯学部・附属病院, 医員
AKIYAMA Shigehisa Osaka University Dental Hospital, Senior Instructor, 歯学部・附属病院, 助手 (00283797)
|Budget Amount *help
¥3,700,000 (Direct Cost : ¥3,700,000)
Fiscal Year 1999 : ¥1,100,000 (Direct Cost : ¥1,100,000)
Fiscal Year 1998 : ¥2,600,000 (Direct Cost : ¥2,600,000)
It is widely known that individuals with Down syndrome (DS) often develop severe periodontal diseases. Although Actinobacillus actinomycetemcomitans is suspected to be a causative pathogen, it is still unclear which pathogens are predominantly involved. In this study, we surveyed the periodontal pathogens harboring in DS population to determine if specific pathogens are involved in the etiology of the periodontal diseases.
The subjects were 120 children including 60 DS children (2-13 years old, 5 subjects in each age bracket) and 60 agematched controls, and 62 DS adults (14-57 years old). Ten pathogens, Porphyromonas gingivalis, A. actinomycetemcomitans, Bacteroides forsythus, Treponema denticola, Prevotella intermedia, P. nigrescens, Capnocytophaga ochracea, C. sputigena, Campyrobacter rectus, and Eikonella corrodens were surveyed in subgingival plaque samples using a polymerase chain reaction. Periodontal status was evaluated by pocket probing depth, bleeding on probing, and gingival
No significant difference in periodontal status was observed between the DS and control groups, however, all of the pathogens were detected with greater frequency in the DS children. B. forsythus, T. denticola, P. nigrescens, and C. rectus were significantly prevalent throughout all age brackets of the DS children (p<0.01 or 0.05). The occurrence of P. gingvalis was also significant in the DS subjects over 8 years old. A cluster analysis of the microbial profiles of the DS subjects showed that gingivitis was associated with increased varieties of the harboring pathogens and the distribution of P. gingivalis.
The bacterial occurrences were analyzed in 62 DS adults (14-57 years old) with healthy or diseased periodontal status. The prevalence of P. gingivalis showed the relationship to severity of periodontitis in 14-35 yeas old DS subjects. Whereas, a majority of the older DS subjects (36-57 yeas old) showed advance periodontal destruction despite of bacterial profiles. To clarify the prevalence of specific genptypes of this organism, the distribition of four genotypes of fimA gene of P. gingivalis was further investigated in the subjects. P. gingivalis possessing type II or type Ib fimA gene was found to be significantly predominant.
These results suggest that colonization by various periodontal pathogens can occur in quite early childhood of the DS population. It is also suggested that P. gingivalis with specific genotypes promote the disease progression in DS adults. Less