The Vancouver microstomia orthosis.

Eighteen microstomia orthoses are compared with respect to their characteristics, use, and limitations. A new prosthesis, the Vancouver microstomia orthosis, was designed to incorporate the advantages of many of the orthoses and eliminate some drawbacks. Ten adults with microstomia secondary to second- or third-degree circumoral flame burns were fitted with the prosthesis and observed over a 12-month period. In 9 weeks or less, microstomia was corrected with an average gain of 7 mm in the horizontal and 13 mm in the vertical active range of motion. The measures before and after this treatment were statistically significant for increase in both dimensions (paired t-test, p less than .01).