accuracy of cbct measurements of posterior mandible

Objectives: this study is aimed at analysing the accuracy and reliability of the cone beam ct(cbct) measurements and direct physical measurements of the posterior mandible.materials and methods: eighteen cadaveric hemi-mandibles were dissected from the softtissues and the cbct images of the mandibles were taken. direct physical and cone beam ctmeasurements of six landmarks which includes height of ramus (r), distance of lingula to sigmoidnotch (ls), distance of lingula to inferior border (li), position of lingula in relation to occlusalplane (l-op), ramus thickness at crestal level (rt-c), and ramus thickness at midway betweensigmoid notch and lingula (rt-m) were determined. accuracy and reliability of the measurementswere tested.results: four landmarks showed high accuracy when measuring the posterior mandible, whiletwo landmarks, li and rt-m, showed statistically significant weaker accuracy (p<0.05). inter-reliabilitywere good for all landmarks when measured directly physically on mandibles (icc>0.7and p>0.05), but were low on two landmarks, li and rt-c, on cbct measurement (icc<0.5 andp<0.05).conclusion: a generally strong accuracy between direct physical and cbct measurementsfor most landmarks on posterior mandible were found. reliability between two researchers werehigh on direct physical measurements. meanwhile, two landmarks on cbct which include liand rt-c showed low inter-reliability. hence, cbct measurements proved to be a good tool forpre-operative assessment,