title: The potential of cohesive silicone for facial prosthetic use: a material property study and a clinical report.
abstract: OBJECTIVE
  Prosthetic reconstruction of a facial defect can help to reduce disfigurement and restore the social functioning of the patient. Several methods for holding a prosthesis in place exist, including the use of osseointegrated implants and medical adhesive agents; however, since the treatment options for some patients may be restricted by various health conditions and other limitations, including allergies to adhesive agents, a history of radiation therapy, and financial issues, other options that suit individual demands are required. The objectives of this study were to test the hypothesis that adhesive characteristics could be bestowed on silicone elastomers by altering their catalyst/base silicone ratios (CBR) and to examine the effect of the thickness of the cohesive silicone layer of a prosthesis on its initial adhesive strength.
  
  
  METHODS
  The adhesive strengths of specimens with CBRs ranking from 1/10 to 1/70 were examined by the rolling ball tack test. A tensile test was used to evaluate the tensile adhesive strengths of specimens made of layers of cohesive silicone (CBR 1/60) and normal silicone (CBR 1/10) with different thicknesses. Auricular prostheses containing cohesive silicone on the skin side were applied to a 50-year-old man with defects in both auricular regions and with reduced manual dexterity due to serious burns.
  
  
  RESULTS
  The rolling distance was reduced with a decrease in CBR, and a thinner cohesive silicone (CBR 1/60) layer demonstrated a higher peak load. On clinical application, the adhesion of the auricular prosthesis containing cohesive silicone was improved by expanding the adhesive area and altering the thickness of the cohesive silicone layer, resulting in sufficient adhesion and easier handling than that achieved using an adhesive agent 1 year post delivery.
  
  
  CONCLUSIONS
  These results suggest that cohesive silicone can be used as a glueless retentive material for facial prostheses.
authors.affiliation: Tohoku University Hospital, Maxillofacial Prosthetics Clinic, Aoba-ku, Sendai, Japan. koyama@dent.tohoku.ac.jp
authors.forename: Shigeto
authors.initials: S
authors.lastname: Koyama
authors.forename: Keiichi
authors.initials: K
authors.lastname: Sasaki
authors.forename: Soshi
authors.initials: S
authors.lastname: Hanawa
authors.forename: Naoko
authors.initials: N
authors.lastname: Sato
mesh_terms: D000268:Adhesiveness; D000328:Adult; D004129:Dimethylpolysiloxanes / Q000737:chemistry*; D004431:Ear, External; D006801:Humans; D008297:Male; D008422:Materials Testing; D008447:Maxillofacial Prosthesis; D019563:Mechanics; D008875:Middle Aged; D010328:Patch Tests; D019736:Prostheses and Implants; D011474:Prosthesis Design; D012826:Silicone Elastomers / Q000737:chemistry*; D013718:Tensile Strength; D055815:Young Adult
chemical_list: C076788:A 2186; D004129:Dimethylpolysiloxanes; D012826:Silicone Elastomers