Distribution of 10 periodontal bacteria in saliva samples from Japanese children and their mothers.

OBJECTIVE: We analyzed the distribution of 10 periodontal bacteria species (Porphyromonas gingivalis, Tannerella forsythensis, Prevotella intermedia, Prevotella nigrescens, Campylobacter rectus, Eikenella corrodens, Actinobacillus actinomycetemcomitans, Capnocytophaga ochracea, Capnocytophaga sputigena, and Treponema denticola) in children, and then compared their distribution in those children and their mothers, with special attention given to three of the species known as the red complex (P. gingivalis, T. forsythensis, and T. denticola) whose presence has been shown to be associated with conditions related to periodontal diseases. METHODS: One hundred thirteen pairs of children and their mothers were randomly selected from patients treated at the Pedodontic Clinic of Osaka University Dental Hospital. Saliva samples were taken at the second visit prior to receiving professional tooth brushing instruction. Genomic DNA was extracted from each saliva sample, followed by a polymerase chain reaction assay with species-specific sets of primers. RESULTS: A. actinomycetemcomitans was the most frequently detected species in the mothers, followed by C. sputigena, P. gingivalis, and T. forsythensis, while C. sputigena had the highest detection rate, followed by A. actinomycetemcomitans and T. denticola in the children. The detection rate of the red complex species in children whose mothers possessed the same species was significantly higher than in those whose mothers did not possess them. CONCLUSIONS: Our results indicate a correlation between the presence of periodontal bacteria in children and their mothers, while the presence of red complex bacteria in children was highly associated with that in their mothers.

Distribution of Porphyromonas gingivalis fimA genotypes in Japanese children and adolescents.

BACKGROUND: Porphyromonas gingivalis is considered to be one of the most important pathogens in periodontal disease and its fimA genes have been classified into six variants (types I through V and Ib). A majority of the P. gingivalis organisms isolated from periodontitis patients are type II, followed by type IV, while type I is prevalent in healthy adults. METHODS: A total of 650 saliva samples were taken from 464 children (3 to 18 years of age), who visited Osaka University Dental Hospital. Genomic DNA was extracted from each sample and analyzed using a polymerase chain reaction (PCR) method with P. gingivalis-specific primers, followed by an additional PCR assay to determine the fimA genotypes for P. gingivalis- positive subjects. RESULTS: Fifteen (3.23%) of the subjects were P. gingivalis-positive and none of those samples showed a positive reaction to the type II fimA-specific primers, while four, one, and two subjects were shown to be positive for the type I, Ib, and III genotypes, respectively. In addition, the type IV genotype was detected in three subjects in the older age group. CONCLUSIONS: Our findings suggest that a limited number of children harbor P. gingivalis, and that the distribution of type II and IV fimA genotypes is extremely low. Further, some adolescents were found to possess the type IV fimA genotype which has been shown to be possibly related to adult periodontitis, in contrast to types I, III, and V.

Occurrence of periodontal bacteria in healthy children: a 2-year longitudinal study.

OBJECTIVES: To examine the occurrence of specific periodontal bacteria in children and adolescents. METHODS: Ten putative periodontal bacteria were longitudinally examined in plaque and saliva samples from 119 periodontally healthy children (2-15 years old) using a polymerase chain reaction method. RESULTS: Capnocytophaga ochracea, C. sputigena, and Actinobacillus actinomycetemcomitans were frequently found in saliva, and tended to persist in saliva for the remainder of the study, whereas Porphyromonas gingivalis, Treponema denticola, and Prevotella intermedia were rarely detected. P. nigrescens was more frequently detected in plaque and its prevalence increased with age. Eikenella corrodens and Campylobacter rectus were sometimes detected in both plaque and saliva, while Tannerella forsythensis was occasionally detected in saliva. CONCLUSION: A. actinomycetemcomitans, C. ochracea, C. sputigena, P. nigrescens, C. rectus, and E. corrodens are common members of the oral microbial flora of healthy children, whereas P. gingivalis, P. intermedia, and T. denticola appear to be transient organisms.

Clinical and microbiological changes in a child with rapid alveolar bone loss and refill.

A 10-year-old Japanese girl with severe tooth mobility in her lower permanent incisors was examined clinically, as well as radiographic and microbiological means. The incisors had severe alveolar bond loss and pocket depths exceeding 7 mm at the first visit, however, 10 periodontal bacteria were not detected in subgingival plaque samples taken from the lower central incisors using a 16S rRNA-based polymerase chain reaction method. Periodontal treatment consisting of mechanical debridement and antibiltic medication resulted in a significant improvement of the clinical parameters. Three months after the first examination, dental radiographs showed refilling of alveolar bone in the region. Further, microbiological examinations after remission detected only oral microflora commonly found in health children including A. actinomycetemcomitans. Based on the clinical, readiographic, and microbiological findings, the present case was diagnosed as acute periodontitis.