Facial paralysis grading system: A new and simple Smile Excursion Score for evaluating facial reanimation surgery

Background: Various facial paralysis grading systems have been introduced to evaluate the results of both spontaneous recovery and facial palsy reconstruction. The aim of the present study was to introduce and evaluate an objective new and quick Smile Excursion Score system which is readily applicable and easy to follow. It has been applied over the past 25 years for preoperative and postoperative result evaluation of smile reconstruction at Chang Gung Memorial Hospital. Methods: A standardized evaluation method was described for the assessment of the upper lip movement preoperatively and postoperatively with at least 1 year follow-up after functioning muscle transplantation. The evaluation was scored by the number of maxillary teeth exposed when smiling with teeth showing. Reliability of this technique was assessed by using 3 independent examiners who each evaluated the smiles of 34 unilateral facial paralysis patients 4 times, creating 408 sets of measurements. Results: The intraclass correlation coefficients for interrater and intrarater reliability exceeded 0.94, which is considered as excellent and reliable. Conclusions: Chuang's Smile Excursion Score system is simple, quick, and accurate in evaluating smile after reanimation of paralyzed face effecting free functional muscle transplantation with no additional tools.