GP5a - Oral Adverse Outcomes Associated with the Buccal Mucosa Graft for Urethroplasty

Abstract: The buccal mucosal graft (BMG) has become the standard graft material in reconstructive urology due to its large surface area and compatibility.1 Currently, there are 3 methods to manage the BMG donor site, including primary closure, healing via secondary intention, and graft-assisted closure. The ideal technique for managing the BMG donor site remains disputed, as postoperative oral complications have been reported with all 3 techniques. Based on prior studies, the researchers hypothesize that larger BMG grafts are associated with more oral adverse outcomes.2 This study sought to ask the following research question: In subjects undergoing urethroplasty with BMG, does the method of donor site management (closure, non-closure, or xenograft-assisted closure) have an association with long-term postoperative oral adverse outcomes?

A retrospective cohort study was conducted, enrolling a sample of patients treated at Harborview Medical Center, Seattle, WA, between January 2012 and December 2018. Eligible subjects had a history of urethroplasty utilizing a unilateral BMG treated more than 2 years ago. An IRB-approved survey was designed to assess oral adverse outcomes using a Likert scale for responses. Predictor variables were donor site management methods, defined as closure, non-closure, and xenograft-assisted closure. The primary outcome variables were presence/absence of postoperative oral adverse outcomes, defined as subjective changes in mouth opening, smile, chewing, speech, intraoral bleeding, paresthesia, trismus, and infection. Other study variables included the BMG surface area, review of oral rehabilitation instructions, and patient satisfaction. Descriptive, univariate, and multiple linear regression statistics were computed, with statistical significance set at P < .05.

The sample was composed of 137 subjects (95% male; mean age 48 years). The mean surface area of the BMG for closure, non-closure, and xenograft was 1059mm2, 1178mm2, and 1228mm2, respectively. Thirty-nine patients replied to the survey (response rate 29%); after applying exclusion criteria, 34 were included in the analysis (7 closure, 17 non-closure, and 10 xenograft-assisted closure). Univariate analyses between survey questions and donor site management methods did not show significant differences in subjective paresthesia, change in speech, smile, chewing ability, mouth opening, trismus, or satisfaction. Multiple linear regression was performed to assess the effect of BMG surface area on the association between type of wound closure and survey responses. The xenograft group was associated with the best-rated ability to chew and decreased trismus, when accounting for larger graft surface area (P < .01). Although not statistically significant, multiple trends suggest xenograft-assisted closure out-performed primary closure and non-closure with respect to changes in speech, smile, mouth opening, and satisfaction with increasing graft sizes. Conversely, with increasing graft size, the xenograft group was associated with more paresthesia. Seventy-seven percent of survey respondents reported that they did not receive oral rehabilitation instructions.

This study suggests that xenograft-assisted closure may reduce long-term oral adverse outcomes associated with trismus, subjective changes in chewing, mouth opening, speaking, and smiling with larger graft sizes. However, increased BMG surface area was associated with paresthesia in this group. Additional studies with a larger sample size are needed to support these findings. Finally, regardless of closure method, the researchers note a lack of postoperative patient education for oral rehabilitation exercises and wound care. The addition of this practice will improve long-term outcomes associated with intraoral healing.


References: 1. Wong E, et al: Does closure of the buccal mucosal graft bed matter? results from a randomized controlled trial. Urology 84:1223, 2014
2. Soave A, et al: Substitution urethroplasty with closure versus nonclosure of the buccal mucosa graft harvest site: a randomized controlled trial with a detailed analysis of oral pain and morbidity. Eur Urol 73:910, 2018