Changes in the buccolingual polished surfaces of the mandibular denture following anterior vestibuloplasty with free skin grafting and mylohyoid ridge resection

Abstract

lh’ 1s article assesses the changes in the lower denture space brought about as a direct result of mandibuiar preprosthetic surgery. Patients who have markedly resorbed alveolar ridges must depend increasingly on the use of the lips, cheeks, and tongue against the polished surface of the denture to obtain denture stability. Because of continuous bone resorption, however, the lips and cheeks loose their support and show a tendency to fall into the oral cavity. The tongue also appears to expand into the space formerly occupied by the teeth. All of these factors combine to reduce the space available for the denture. The anterior vestibuloplasty described by Hopkins et al.’ deepens the labial sulcus by removing the soft tissue attachments. This increases the space and height of the ridge available for supporting mandibular dentures. The lowering of the floor of the mouth on the lingual side increases the stability. The object of the surgery is to increase the denture foundation and improve the quality of the tissues available for support. The surgery will also have an affect on what Brill et al.’ termed the dynamic mandibular denture space. Various methods have been used to determine the shape of the buccolingual neutral zone. Russell,3 using wax softened with mineral oil, recorded a dynamic impression of this zone. A modification of this technique was described by Raybin. Matthews et a1.5 advocated the use of alginate (irreversible hydrocolloid) but this material does not support its own weight and there are problems over the control of the setting times. As it sets, there is a sudden development of an elastic memory, making it unsuitable for long-term functional molding. Murphy6 used Kerr’s No. 4 Korrectawax (Sybron/Kerr, Romulus, Mich.) in a dynamic way. Heath’ developed a nonsetting silica gel based upon a polymer of dimethyl siloxane filled with 12% calcium silicate. This technique was also used by Neil1 and Glaysher.8 Beresin and Schiesser9 suggested the use of low-fusing modeling