Longitudinal survey of the distribution of various serotypes of Streptococcus mutans in infants

Abstract

The establishment of various serotypes of Streptococcus mutans was studied serologically in plaque samples collected from labial surfaces of upper primary incisors of 22 infants (starting age, 5 to 13 months) over a period of 30 months. Clinical examinations were also performed. No clear-cut association between the initiation of dental caries and previous detection ofS. mutans was noted. However, all 12 of the infants with caries had S. mutans isolated at some time during the course of this study. The most common serotype isolated at the initial establishment of S. mutans on the tooth surfaces was serotype c, whereas types d, e, and g became established in a few cases. During the test period, changes in the distribution of serotypes of S. mutans were observed in some cases. The initiation of carious lesions could be found in a few cases even when S. mutans comprised about 1% or less of the total streptococcal count of the specimen from the tooth surfaces. Serotype dlg strains tended to develop carious lesions on smooth surfaces, although serotype c was isolated from almost all individuals who developed caries.

The relationship between bottle usage/content, age, and number of teeth with mutans streptococci colonization in 6–24‐month‐old children

“…When examined separately, age, number of teeth, and bottle usage/content were each found to be associated with the presence of MS. The observation that the percentage of children colonized with MS increases with age and number of teeth also has been reported in previous studies of preschool children (7,27). However, since age, number of teeth, and bottle usage/content are related to one another as well as to MS colonization, the apparent associations between each of these variables and colonization with MS may have been confounded in the unadjusted analyses.…”

“…The age at which a child becomes colonized is important since some studies suggest that the earlier mutans streptococci colonize a child's mouth the higher the caries experience (4,5). A recent study concluded that the acquisition of mutans streptococci occurs between 19 and 31 months of age (6), although other studies have reported that younger children may be colonized (7)(8)(9).…”

Streptococcus mutans establishment and dental caries experience in children from 2 to 4 years old

“…The caries prevalences of the study populations in earlier longitudinal studies by CARLSSON et al (2) and MASUDA et al (5) were higher than in the present study, but so, too, were the isolation frequencies of S. mutans in corresponding age groups. These studies confirmed the relationship between the prevalence of S. mutans in the plaque and the development of caries.…”

“…These studies confirmed the relationship between the prevalence of S. mutans in the plaque and the development of caries. The isolated S. mutans strains all belonged to serotype c/e/f, whieh was found to be the most common serotype group in many studies (5,10,19,20).…”

“…Studies of Streptoeoeeus mutans strongly suggest its active involvement in the initiation and progression of dental earies; the organism does not beeome established in the mouths of infants during the first year (1)(2)(3)(4)(5)(6)(7)(8).…”