Use of custom-made conformers in the treatment of ocular defects.

The loss of an eye is often followed by scar tissue contracture. The purpose of this article is to describe a procedure for fabricating acrylic resin ocular custom-made conformers to maintain socket size and contour. These custom-made ocular conformers act as an interim measure and as valuable diagnostic indicators of problems experienced by the patients. While stock conformers merely maintain the socket size and prevent scar tissue contractures, the custom-made conformers can also be used to enlarge unfavorably small sockets, stimulate eyelid movement, aid hygiene, help the clinician develop the final shape for the definitive prosthesis, and reduce the amount of postinsertion adjustments needed. These advantages and the ease of fabrication make custom-made conformers a viable initial treatment option in patients with ocular defects.

An evaluation of the surface characteristics of a facial prosthetic elastomer. Part III: Wettability and hardness.

Silicone facial prosthetic elastomers may cause tissue damage by abrasion. Such damage is a particular concern when prostheses are mechanically retained against tissues compromised by adjunctive therapy. The hardness and wettability of Cosmesil material was compared with that of Molloplast-B material. The stone test surfaces were separated with soap, sodium alginate, silicone paste, and left untreated. A polished stainless steel surface was prepared as a control. The specimens of Cosmesil and Molloplast-B materials were processed against each of these surfaces. Ten specimens of each material were processed against the five different surfaces. Wettability was evaluated by measuring the contact angle with a profile projector. Indentation hardness was measured with a Shore-A durometer. Statistical analysis involved multiple analyses of variation and Tukey's procedures (in all cases p less than 0.05). Molloplast-B material was found to have a higher wettability than Cosmesil material (means = 3.22 degrees higher); sodium alginate separator yielded silicone specimens with the highest wettability; Molloplast-B material was found to be harder than Cosmesil material (means = 9.75 Shore-A indentation units harder). The softest silicones were processed with soap separator. Silicone grease yielded the hardest specimens. The mechanical performance of Cosmesil material would be enhanced by increasing the surface wettability. The hardness of Cosmesil material is within the ideal range for a maxillofacial prosthetic elastomer.

An evaluation of the surface characteristics of a facial prosthetic elastomer. Part II: The surface texture.

Silicone elastomers do not have an inherent surface texture but take on the surface texture of the surface against which they are processed. This study compares the surface texture of Cosmesil material, a purpose-designed facial prosthetic elastomer, and Molloplast-B material, which is a well-established material for use in the clinic. We used a profilometer to determine the roughness average, maximum roughness, and waviness of the dies, control, gypsum, and silicone test surfaces. Statistical analyses of results involved multivariate analyses of variance and Tukey's procedures to compare roughness average, maximum roughness, and waviness (in all cases p less than 0.05). The results showed that the silicone elastomers, Cosmesil and Molloplast-B, have similar surface characteristics. The only statistically significant difference was in waviness (Molloplast-B, means = 10.82 microns; Cosmesil, means = 12.82 microns). The gypsum surface yielding the most satisfactory result was the surface that had been treated with silicone paste separator. On the basis of surface characteristics, Cosmesil material is likely to cause no more surface trauma of the tissue against which it is placed than the use of Molloplast-B material.

An evaluation of the surface characteristics of a facial prosthetic elastomer. Part I: Review of the literature on the surface characteristics of dental materials with maxillofacial prosthetic application.

Silicone elastomers are used to construct a wide variety of maxillofacial prostheses and appliances. These applications dictate that an elastomer-tissue interface is present. The behavior of this interface will vary according to the method of retention of the prosthesis, the nature of the tissue surface, and whether the prosthesis is externally applied or occupies an intratissue location. Understanding the behavior of the silicone-tissue interface is consequently important. Part I of this series of three articles is a review of the literature on the surface characteristics of dental materials with maxillofacial prosthetic application. The review considers surface texture, indentation hardness, wettability, and reaction of tissues to surface texture of restorative materials.