CHAPTER 23 Interim Removable Partial Dentures
Tooth replacement is required for a variety of reasons. Sometimes replacements may be necessary for shorter periods of time that serve alternative purposes than permanent replacement, such as while tissue is healing or related treatment is being provided. When such applications require the temporary use of removable partial dentures, their fabrication and use must be incorporated into a total prosthodontic treatment plan.
These various uses of interim prostheses for the partially edentulous mouth strive to achieve temporary goals with minimum time and expense. These prostheses are typically resin with wire retention and may include components to provide tooth support. The difficulty in achieving and maintaining strategic tooth support and stability with such prostheses makes it important that patients be made aware that these prostheses are temporary and may jeopardize the integrity of adjacent teeth and the health of supporting tissue if worn for extended periods without supportive care.
For the sake of appearance, an interim removable partial denture may replace one or more missing anterior teeth, or it may replace several teeth, both anterior and posterior. Such a restoration is usually made of resin, which may be produced by a sprinkling method, by the visible light-cured (VLC) method, or by waxing, flasking, and processing with autopolymerizing or heat polymerizing resin (Figure 23-1). It may be retained by circumferential wrought-wire clasps, Crozat-type clasps, interproximal spurs, or wire loops.
Figure 23-1 A, Although loss of mandibular teeth does not always have a significant esthetic impact, this interim removable partial denture was needed because of the visibility of the mandibular incisors. Provision of the mandibular left molars allowed early accommodation of the residual ridge during the temporary prosthesis period. B, Tissue surface of the interim prosthesis revealing a rounded lingual flange and a tapered labial flange. The latter was needed to improve lip movement and reduce the feeling of bulk, both of which enhance normal lip activity.
When a space results from recent extractions or traumatic loss of teeth, it is usually prudent to maintain the space while the tissue heals. In younger patients, the space should be maintained until the adjacent teeth have reached sufficient maturity to be used as abutments for fixed restorations, or so that an implant can be placed. In adult patients, maintenance of the space can prevent undesirable migration and extrusion of adjacent or opposing teeth until definitive treatment can be accomplished (Figure 23-2).
Figure 23-2 A, Malpositioned maxillary anterior teeth require extraction. Following a period of healing, the patient will decide on a definitive treatment option, which may include a removable partial denture or an implant-supported prosthesis. Because the length of time until definitive care will be provided is not known, a temporary interim prosthesis not only replaces esthetically important teeth but provides stabilization of adjacent and opposing dentition as well. B, Occlusal view of the interim prosthesis showing clasp placement at the most posterior locations without crossing of the occlusion and anterior positions bilaterally. Full palatal coverage allows less stress to the remaining maxillary dentition and may prevent prosthesis-induced gingival trauma as well as tooth movement.