Can radiographic features predict the difficulty of open exposure of palatal canines?

Aim The aim of this study is to determine if radiographic features are predictive of surgical difficulty of open exposure of palatal canines using a tissue sacrifice method. Materials and methods This is a prospective case series comparing features observed on preoperative panoramic radiographs and other variables to both surgical duration and the surgeons reported difficulty. Radiographic features included height, sector (overlap of adjacent incisor) and angulation of the impacted canine. Clinical variables recorded were patient age and gender, side of impaction, anaesthetic choice, if the canine was palpable, and patient cooperation. A stepwise linear regression analysis was used to relate clinical and radiographic variables to treatment duration and assessed difficulty. Inter- and intra-examiner reliability were assessed with Kappa statistics. Results Forty-nine patients with a total of 55 palatal canine exposures were included. The mean duration of exposure was 4 min and 5 s with a range of 45 s to 8 min and 50 s. Surgical duration was correlated to a subjective grade of surgical difficulty recorded on a visual analogue scale by the surgeon ( Pearson's correlation coefficient 0.76). Three predictors of increased surgical duration were identified as anaesthetic choice, height and angulation of impaction. The linear regression had an accuracy of 30.5%. Conclusions Radiographic features had a small predictive value in determining duration of open palatal canine exposure. Both increased height and angulation to the midline were associated with longer procedures. The use of local anaesthetic was associated with a longer surgical duration compared with general anaesthetic. [ABSTRACT FROM AUTHOR]