No abstract

A~~i~~( .~-D e n t i n a l voids in the permanent teeth of sixteen children were detected over an eighteen-month period. The lesions were apparently present prior to tooth eruption and their radiographic appearances closely resembled that of dentinal caries. All lesions were found beneath fissures or pits suggesting a developmental aetiology. Their relationship to caries susceptible sites makes the lesions particularly prone to caries involvement.

External resorption may occur following loss of the external root surface. Occlusal trauma may be a propagating stimulus for progressive resorption. Lesions may sometimes be non-progressive, and treatment may therefore be more damaging than observation.

h a retrospective study of the records of 510 final-grade primary school children, caries experience in the occlusal surfaces of homologous right-left pairs of first permanent molar teeth was analysed. It was 44.4 per cent of maxillary, and 32.6 per cent of mandibular pairs of surfaces showed unilateral caries experience.The initial caries attack in pairs of surfaces with bilateral caries experience occurred at a significantly earlier age than in the group with unilateral caries experience @*O.OOI). In addition, the interval following the initial attack during which the remaining tooth in each pair remained sound was analysed. Highly significant differences were found between the groups with unilateral and bilateral caries experience @*0.001). The findings have implications for the design of investigations using the half-mouth technique. * Volker JF. Russell DL. The epidemiology of dental caries. In: Finn SD. Clinical pedodontics. 4th ed. Philadelphia: WB Saunders, 1973:472. Gray PG, Todd JE. Slack GL, Bulman JS. Adult dental health in England and Wales in 1%8. London: Her Majesty's Stationery Office, 197054. ' Todd JE. Children's dental health in England and Wales 1973. London: Her Majesty's Stationery Office, 1975:26. ' h a n DS. Slack GL. Dental caries in English school children. A longitudinal study. Br Dent J 1972;133:529-38. ' Walsh JP, Smart RS. The relative susceptibility of tooth surfaces to dental caries and other comparative studies. NZ Dent J 1948;44:17-35. ' Jackson D, Burch PRJ, Fairpo CG. RightAeft asymmetry of caries at mesial and distal surfaces of permanent teeth. Br Dent J 1979;147:237-40. ' Carr LM. Dental health of children in Australia 1977-1982. Aust Dent J 1983;28:269-76. " Walton JL. Dentin radiolucencies in unerupted teeth: report of two cases.