Integrated surgical approaches for caustic ingestion-induced microstomia

Caustic ingestion-induced microstomia causes profound functional impairment, which limits mouth opening, speech, feeding, and overall quality of life, particularly in children. Published management strategies are heterogeneous and lack a standardized treatment protocol.

We conducted a PRISMA-compliant systematic review (PROSPERO CRD420251106502) of the literature on caustic ingestion-induced microstomia and present a series of 11 patients treated using a standardized institutional protocol. Data collected included demographics, causative agents, surgical techniques, appliance use, intercommissural and interincisal distances (ICD and IID) measurements, follow-up, complications, and functional outcomes.

The literature review identified 13 studies with 19 patients (published 1989-2021). Techniques reported were heterogeneous, and postoperative appliance use was inconsistently described. In our institutional series (11 patients; mean age 9.4 years, range 1-51), 18 commissuroplasties were performed. An integrated protocol of scar release, local mucosal flap transfer, split-thickness skin grafting (STSG, from native or expanded donor sites), selective local mucosal flaps, and customized intraoral vestibular appliances was used. Mean ICD increased from 17.3 mm to 34.0 mm and mean IID from 11.0 mm to 22.8 mm. Complications (mostly minor) were related to pre-existing dental compromise, appliance-related mucosal irritation, and the underlying caustic injury.

A multimodal strategy that couples reliable intraoral resurfacing (STSG) and donor-site optimization (tissue expansion) with standardized postoperative appliance therapy and multidisciplinary follow-up yields durable functional gains. The protocol's complexity and resource requirements limit immediate generalizability; however, the principles are transferable and may guide other centers.