Esthetic Oral Rehabilitation with Mandibular Telescopic Overdenture Opposing Maxillary Fixed Dental Prosthesis- a Case Report

INTRODUCTION

A telescopic denture also known as overdenture or overlay denture is a removable dental prosthesis that covers and rests on one or more remaining natural teeth, the roots of natural teeth, and/or dental implants.¹ These dentures have a full coverage milled primary coping which is cemented to the prepared teeth and a secondary coping which is incorporated into the denture. The secondary coping fits over the primary coping and provide retention by friction fit and interfacial surface tension mechanism.^2,3 These two mechanisms are depends on the tapered configuration of the contacting walls. Smaller the degree of taper, greater the frictional retention of prosthesis.⁴

Overdenture offers many advantages over conventional denture. Overdenture incorporates remaining teeth which enhances retention and support. It reduces the amount of residual ridge resorption as forces are transmitted to the long axis of teeth and provides proprioception by preserving the periodontal membrane.⁵ Telescopic overdentures can also be given in case of periodontally compromised teeth as it disperses the forces thereby preventing pathologic migration.²

CASE REPORT

A 65-year-old male patient reported to the department of Prosthodontics with a chief complaint of missing teeth. History revealed extractions due to caries and periodontal disease around 1 year back. Intraoral examination revealed retroclined anterior maxillary teeth, supraeruption i.r.t. 21,22 and missing all mandibular teeth except 32,33 and 43 (Fig. 1). Grade III mobility was seen. After explaining various treatment options to the patient, a treatment plan was formulated to preserve 33 and 43 and to make a mandibular telescopic overdenture retained by stud attachments against maxillary fixed dental prosthesis.

Extraction was done i.r.t. tooth 32. Root canal treatment of tooth 14, 13, 12, 11, 21, 22, 24, 33 and 43 was done. For the maxillary teeth, tooth preparation was done (Fig. 2) followed by final impression with polyvinyl siloxane elastomeric impression material by double step putty wash technique and temporization (Fig. 3). After 1 week, metal ceramic crowns were cemented with glass ionomer cement.

Coronal height of the mandibular teeth were reduced 3 mm short of marginal gingiva and shaped like a dome (Fig.2). After the preparation of the abutments, the impression was made by using a polyvinyl siloxane elastomeric impression material by double step putty wash technique. The impression was poured with Type III stone to obtain a cast on which the primary copings were fabricated (Fig. 4). The fit of the primary coping was evaluated in the patient’s mouth, after which they were cemented with glass ionomer cement. Another impression was made by using double step putty wash technique by using a custom acrylic resin tray to obtain a cast on which the secondary copings attached through bar were fabricated (Fig. 5). The fit of the secondary copings over the primary copings was evaluated in the patient’s mouth.

The secondary copings were placed on the master cast, covered with wax (for easy separation during dewaxing) and the trial denture base was fabricated. Occlusion rims were fabricated over the trial denture base. Horizontal and vertical maxillomandibular records were obtained. Mandibular cast was mounted using centric relation record. Teeth arrangement and try-in was done (Fig. 6). Dentures were then processed in a conventional manner, finished, polished and delivered to the patient (Fig. 7 & 8).

DISCUSSION

Telescopic dentures offer many advantages over conventional dentures therefore, extraction of all natural teeth and subsequent replacement with a complete mandibular denture is not the most desirable treatment option. Retaining few natural teeth preserve proprioception, prevent ridge resorption and give a psychological comfort to the patient; which ultimately improves the stability and acceptability of the dentures.^6,7 Teeth which are unsuitable to support a fixed partial denture and a removable partial denture can be conserved and suitably modified to act as abutments under overdentures.⁸ The major advantage offered by telescopic overdentures is retrievability. The dentures can be easily repaired or relined without the need of reconstructing a new prosthesis.

The success of overdenture depends on the condition of the underlying abutments and denture. Therefore, patient should be given proper detailed instructions about the denture maintenance, oral hygiene and periodontal health of abutments.

CONCLUSION

Rehabilitation of partial edentulous arches with overdentures has become a widely accepted treatment modality as it successfully overcome many of the difficulties associated with conventional denture. Modified design with bar attachment fixed to copings as used in this case provides added retention which improves patient compliance and success. Even though implant supported overdentures are used increasingly but tooth supported telescopic dentures should always be advocated as an alternative treatment plan.

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