Attachment loss in primary molars.

The view that primary teeth are only rarely affected by periodontitis has been generally adopted. The aim of the present work was to measure attachment loss and to establish its prevalence, severity and distribution in stained, extracted primary molars. The material consisted of 4 groups of 50 teeth each: first and second upper and first and second lower primary molars. Teeth were selected to fulfil 2 criteria: (1) a carious cavity not extending beyond the cemento-enamel junction and involving only 1 of the proximal surfaces, the other 3 surfaces being sound; (2) root resorption, if present, not affecting more than the apical third of the roots. The teeth were stained in 1% aqueous crystal violet and examined under a stereomicroscope fitted with an ocular micrometer. The distance between the cemento-enamel junction and the most coronal attachment fibres was measured in the mid-line of each surface. Attachment loss was found in 94% of the teeth and on 2/3 of the surfaces. This indicates that periodontitis in primary teeth is not a rare phenomenon. The mean loss of attachment was 0.26 +/- 0.32 mm, which cannot be regarded as clinically important. The maxillary molars and the first molars, and, the proximal surfaces showed more loss of attachment than did the mandibular molars and the second molars, and the buccal and lingual surfaces taken together. This pattern of attachment loss is similar to that seen in permanent molars. On the carious proximal surfaces, significantly more attachment loss was noted than on the sound proximal surfaces.