Masseter-to-facial nerve transfer showed reliability for smile reanimation but with limited impact on resting symmetry.
The researchers noted that no systematic studies have investigated this technique. They conducted a retrospective review of 35 patients with masseteric-facial nerve anastomosis to determine on the effect of preoperative droop oral commissure on symmetry in the postoperative setting. The quality and quantity of dynamic recovery also underwent analysis.
Improvements in Terzis scores occurred in all patients after surgery. More than half of the cohort demonstrated restoration of smile symmetry, defined as Terzis scores of 4 or 5, according to the results.
Eighteen of 35 patients demonstrated improvement in the symmetry scale of oral commissure at rest after the procedure.
Mean decreases were observed for both the altitude difference of oral commissure excursion (AD-OCE) and altitude difference of bilateral oral commissure position (AD-OCP) after surgery. Postoperative AD-OCP was significantly impacted by preoperative symmetry.
The researchers transformed improvements in both dynamic and static symmetry into a single factor called "α". Results indicated that the dynamic value was significantly greater than the static value.
“Assessing the preoperative symmetry of oral commissure at rest can be used to predict postoperative outcomes, and patients with severely droop oral commissure (symmetry scale III or IV) should receive static suspension,” the researchers concluded. – by Rob Volansky
Disclosure: The researchers report that the study was funded by the Youth Fund of National Natural Science Foundation of China.