Fabrication of a Gingival Mask: A Removable Gingival Replacement Unit
Thomas J. Balshi, DDS, PhD, FACP and Glenn J. Wolfinger, DMD, FACP
When patients lose teeth, they also lose the supporting alveolar bone and gingival architecture. Surgical procedures are available today to rebuild these deficits and to provide an esthetic framework for tooth replacement. However, when surgical procedures are contraindicated, or when it is impossible to adequately replace the amount of lost gingival architecture, prosthetic replacement is indicated.
Removable dentures routinely incorporate the lost gingival tissue in the flanges using shades of pink-colored acrylic resin. Porcelain fused to metal bridges, either supported by natural teeth or implants, may include pink-colored porcelain to achieve the same result. This allows replacement of the soft- and hard-tissue deficits without leaving dark spaces between the teeth and soft tissue or having large clinical crowns. Although some clinicians may argue that this design may inhibit proper oral hygiene maintenance, the authors have not experienced this to be a problem.
A technique is available for crown and bridge restorations to replace the missing soft-tissue contours independent of a fixed prosthesis. This is accomplished by means of a removable gingival replacement unit, sometimes referred to as a gingival mask.
- Sever undercuts should first be blocked out using soft orthodontic wax.
- The area to be gingivally restored should then be lubricated with a water insoluble agent such as pure petroleum jelly to facilitate removal (Fig. 1)
- A piece of Triad visible light-cured resin denture base material (Dentsply, York, PA) is cut to the appropriate size and manipulated to fill the proposed site (Fig. 2). The selection of shades range from light pink fiber, regular pink fiber, dark pink fiber, and regular pink unfiber. The shade should be selected to match the patient’s gingival tone, especially when a partially edentulous space is being restored.
- A plastic instrument and a porcelain carving blade are used to cut and shape the material to the appropriate gingival contours (Fig. 3).
- After shaping is complete, an intraoral light curing unit is used to initially set the material.
- The material is then carefully removed from the mouth. Care must be used to not bend the thin interproximal papilla. The partially cured unit is then placed in the extraoral Triad light curing unit for 8 to 10 minutes.
- When the light-cured polymerization is complete, sharp edges and undercut areas are delicately removed with a slow-speed handpiece.
- The gingival mask is then pumiced, polished, and coated with the air barrier coating (Fig. 5).
- The gingival mask is repositioned in the patient’s mouth, and final adjustments and alterations are made (Fig. 6).
Care must be taken in handling these prostheses. They are usually delicate and can break if not handled properly. Because the gingival replacement unit is a nonfunctional esthetic veneer, the chances of it fracturing intraorally are recommended for all patients because of the higher probability of fracture when handled improperly. Triad visible light-cured resin is the material of choice for the intraoral adaption of this prosthesis. Other materials can also be used to construct a gingival replacement unit using an indirect technique. The prosthesis is retained by creating a mucostatic seal with the site. Only limited mechanical retention, engaging undercuts, is recommended because this will increase the chances of fracture when removing.
Patients should be instructed on proper care of the prosthesis, ie, to handle with care, clean with a brush and denture toothpaste, and soak in water in a denture cup at night.
Applications for a removable gingival replacement unit, or a gingival mask, are as follows: (1) to cover exposed crown margins; (2) to cover exposed implant components; (3) to cover root surfaces and reduce the length of the clinical crown; (4) to block out the black triangles between teeth in which gingival recession has occurred; (5) to fill in the space between the crown and the soft tissue; (6) prevent air flow through or beneath maxillary fixed restoration, improving phonetics; and (7) to provide increased lip and cheek support for those patients who require it.
The advantage of this technique is that it allows for easy replacement of the soft tissue for improved esthetics while permitting easy access or oral hygiene procedures.
The disadvantages are that the gingival mask is fragile and needs to be handled with care or it may fracture, and for those patients who desired a fixed prosthesis to avoid the problems associated with a removable prosthesis, they now have a removable prosthesis again.
In summary, the advantages of the gingival replacement unit are numerous, including improved esthetics and phonetics while maintaining the opportunity for open embrasures and easy access for oral hygiene.
Aside from being a removable prosthesis, the only apparent disadvantage is the potential for fracture because of its delicate nature. However, considering the large population who use ocular prostheses or a similar design and retention concept (contact lenses), patients seem to readily adapt to their use and have been known to wear them for years, even after they fracture.
Esthetic Dentistry Update, Vol. 6, No. 5, October 1995.