Application of Mouth Gag and Temporomandibular Joint Pain and Trismus in Tonsillectomy

Objective: To determine the effect of duration of application of mouth gag on Temporomandibular (TM) joint pain and trismus after tonsillectomy. Study Design: Descriptive study. Place and Duration of Study: Department of ENT and Head and Neck Surgery, Combined Military Hospital, Nowshera, from February to July 2012. Methodology: A total of 40 patients undergoing tonsillectomy, in mouth opening prior to surgery was measured as inter incisor distance in cms. A stop watch was used to calculate the time of application of mouth gag. Mouth opening was again measured 06 hours after the surgery. Difference between the two readings was considered as trismus score and categorized as mild (1 cm), moderate (2 cm) and severe (3 cm). Patient was asked to score pain on a visual analogue scale (0 - 9). Score 0 was categorized as no pain; 1 - 3 as mild pain; 4 - 6 as moderate pain; 7 - 9 as severe pain. Spearman's rank correlation was used for finding correlation between time of mouth gag application and study outcome (pain and trismus). Results: Trismus as observed by difference in inter incisor distance was mild in 11 patients; moderate in 15 patients and severe in 14 patients 06 hours after the surgery. Eleven (27.5%) had mild pain over temporomandibular joint, 15 (37.5%) had moderate and 14 (35%) had severe pain 06 hours after the surgery. Direct relationship was observed between duration of application of mouth gag with postoperative pain and trismus. Significant strong correlation was observed between length of mouth opening to severity of pain and trismus (rs = 0.738; p < 0.001). Conclusion: Duration of mouth gag application should be reduced to cause less TM joint pain and trismus in early postoperative period in tonsillectomy. (author)