Multicenter Trial of Chlorinated Polyethylene Elastomer (CPE) for Maxillofacial Prosthetics

Objectives: CPE is much less expensive than silicone rubber and has application in developing countries. It is molded by laying up colored layers of CPE in a gypsum/polymer flask and heating under pressure to 110°C, followed by surface coloring. A controlled, randomized, prospective, double-blind, single crossover, multicenter Phase III clinical trial was performed to determine the noninferiority of thermoplastic chlorinated polyethylene elastomer (CPE)(experimental) compared to silicone rubber (80% Silastic Adhesive A/20% MDX4-4210A)(control).

Methods: Of the 42 patients enrolled, 71% were male; 82% Caucasian, 2% Asian, 2% Hispanic, 1% African-American; mean age 62 years (range 34-82); 75% had cancer, 14% trauma, 11% birth defects. Patients wore a custom-made prosthesis from each material for 4 months in random order. At the end of each study arm, patients rated how satisfied they were with their prosthesis on a 0-10 scale (10 = completely satisfied). Many other evaluations were made throughout the process, including quality of life measures.

Results: Twenty-eight patients completed the study (22 at M.D. Anderson Cancer Center, 6 at Toronto Sunnybrook Regional Cancer Centre); of these, 68% used silicone prostheses previously. Fourteen patients needed ear prostheses, 10 nose, and 4 orbital (extraoral, full or partial). Overall, patients rated the silicone prosthesis higher than the CPE (8.4ą2.2 vs. 6.2ą3.1 [meanąSD]), difference=2.2, 95% CI=0.9 to 3.6, p=0.017). Previous prosthesis users had a stronger preference for silicone (difference=3.3, 95% CI=1.7 to 4.9, p=0.001), while the 9 patients new to maxillofacial prostheses rated the two materials the same (difference=0.0, 95% CI=-2.1 to +2.1 to +2.1, p=1.00).

Conclusions: Previous users had a strong preference towards silicone, the material with which they were familiar. New users, i.e., those with no previous experience with prostheses, scored the prostheses made with silicone and CPE exactly the same.

Supported by cooperative agreement U01 DE014543 from the NIDCR/NIH.