An assessment of the accuracy of ridge mapping in planning implant therapyfor the anterior maxilla

The use of ridge-mapping to assess bone levels available for implant placem ent in the anterior maxilla avoids some of the problems associated with CT scanning. The aim of this study was to assess the accuracy of ridge-mapping callipers in determining bony ridge widths in the anterior maxilla prior t o dental implant surgery. A modified surgical stent was designed to locate the beaks of ridge-mapping callipers at the same points on the jaw before a nd after mucoperiosteal flap reflection. Eleven subjects were included in t he study. Measurements (n=100) were made at 25 implant sites, 50 "pre-opera tive" and 50 "intra-operative" at 3 mm and 6 mm distances from the crest of the ridge. Then were statistically significant (P<0.0001) differences betw een pre- and intra-operative measurements. Based on pre-operative measureme nts, clinical judgements were made as to whether supplementary procedures s uch as guided bone regeneration would be required. Unanticipated supplement ary procedures were required at 10 fixture sites. The findings indicate tha t ridge-mapping alone is insuficient to accurately predict bone available f or implantation in the anterior maxilla. It is suggested that ridge-mapping may provide reliable information about bone levels when the labial aspect of the anterior ridge is not markedly concave.