Susceptibility of tooth surfaces to carious attack. A longitudinal study

The aim of the present study was to compare semi-longitudinally the pattern of caries experience in proximal, occlusal and smooth surfaces in the dentition and individual teeth of school children and also to reveal the reduced caries activity rate in cohorts of Finnish school children. The series started with a total of 272 children in the four age-groups of 7, 10, 13 and 15 years. The children were given a standardized visualtactile examination augmented with bite-wing radiographs at intervals of 1 year ( ± 1 month) constituting a study period of 3 years. Occlusal caries started at the age of 7 and proximal and smooth-surface caries at age 13 in both boys and girls. The mesial surfaces of the first premolars and the distal surfaces of the maxillary lateral incisors decayed to the same extent as mesial and distal surfaces of the canines, but to a significantly lower extent than their contralateral proximal surfaces. In molar teeth the occlusal surface decayed first, followed by the mesial and distal surfaces whereas distal decay was fastest in mandibular premolars. Decay of the incisor teeth was most pronounced on the mesial surfaces of maxillary lateral incisors. Mandibular incisors remained mostly intact. Our findings point to the importance of the interdental area as a unit in the determination of the time of carious attack on the proximal surface of any tooth.

Section: Discussionsupporting

confidence: 72%

A 3-Year Longitudinal Caries Study of Permanent Tooth Surfaces at Risk in Finnish School Children

Nordblad¹,

Larmas²

1985

“…

The high caries susceptibility of the occlusal surfaces of permanent molar teeth is well known [Walsh and Smart, 1948;Berman and Slack, 1973;Li et al, 1993]. While the pits and fissures of the occlusal groove-fossa system are undoubtedly responsible [König, 1963; Backer Dirks, 1965], research shows that there is no simple association between caries and deep narrow fissures that favour plaque accumulation, as previously thought [König, 1966].

…”

mentioning

confidence: 78%

Fluoride in Enamel Lining Pits and Fissures of the Occlusal Groove–Fossa System in Human Molar Teeth

Pearce

Larsen²,

Coote

1999

The fluoride (F) distribution in enamel lining the occlusal fissures of human molars and premolars is difficult to investigate by normal microsampling techniques, yet this information is of importance as fissures are particularly susceptible to caries. We have used the proton probe to map the distribution of F and Ca in sections of 17 molar teeth collected from Danish and New Zealand populations. The caries status of the sectioned fissure was determined by microradiography or visually after drying. The probe scans were graphed as density images, surface plots and topographical plots. Sound enamel bordering grooves and fissures showed a high–F surface layer, in 1 sample approximately 60 μm wide near the fissure bottom but gradually widening to double this width near the fissure opening, and up to 200 μm wide in grooves, while underlying enamel had a low and almost constant F level. In this respect fissure and groove enamel resembled smooth surface enamel. The F concentration fluctuated along the surface layer, reaching maximum values ranging from 1,800 to 4,200 ppm in 5 non–carious fissures. Incipient caries in fissure enamel usually but not always resulted in an increase in F in the outer layer, the F maximum values in 5 such samples ranging from 1,900 to 7,200 ppm. F maximum values in outer enamel were higher in 7 samples showing advanced caries, 2,700–10,000 ppm. The lesion subsurface body usually showed normal F values, as did carious dentine in the advanced lesions. The variable characteristics of the outer layer in sound fissure enamel are likely to be the result of a developmental process rather than environmental influences. The fact that we normally failed to find increased F concentrations in subsurface carious fissure enamel or in underlying carious dentine suggests that F does not diffuse into the deep part of fissure lesions, and probably has minimal effect on slowing the progress of such lesions, a suggestion in accord with clinical findings on the F effect on fissure caries.

“…This study placed emphasis on the sampling of specific sites, since the prevalence of S. mutans seems influ enced markedly by the sites examined [Ikeda and Sandham, 1971;Hoerman et al, 1972;Shklair ei al., 1972;Street et al, 1976]. Further, variations observed in the decay attack rates of tooth surfaces within the developing dentition [G/asi et al, 1970;Berman and Slack, 1973;Finn, 1973] may be more readily comprehended if individual serotypes displayed significant preferences in their colonization behavior.…”

mentioning

confidence: 99%

Streptococcus mutans Serotypes in Young Schoolchildren

Qureshi¹,

Goldner²,

Riche³

et al. 1977

The frequency of five Streptococcus mutans serotypes (a, b, c, d and e) was investigated in relation to tooth surface and its caries status in young schoolchildren. In the first study, plaque from the five surfaces of a second deciduous molar in 104 five-year-olds was examined for the presence of S. mutans. In the second study, isolations were made from the occlusals and approximal surfaces of a second deciduous and a first permanent molar in five- to eight-year-olds. The isolates were characterized biochemically, and then serotyped with antigen extracts against whole cell and ‘purified’ cell wall antisera using comparative immunoelectrophoresis. Of the 348 plaque isolates, type c was the prevalent serotype (91.1%). In the first study, a significant relation was found between the occurrence of type c and caries on the occlusal surfaces. However, the second study showed type c to be evenly distributed on the occlusals and approximal surfaces irrespective of caries status. This leaves open the possibility that certain types may be commensals.