Restoration of the Occlusal Vertical Dimension with an Overlay Removable Partial Denture: A Clinical Report

The process of tooth loss throughout life associated with severe occlusal wear may pose a challenge in the rehabilitation of partially edentulous arches. In these cases, many therapeutic procedures are necessary because each tooth must be restored to obtain the correct anatomical contour and recover the occlusal vertical dimension (OVD). A removable partial denture (RPD) with occlusal/incisal coverage, also known as an overlay RPD, is an alternative treatment option with fewer interventions, and, consequently, lower cost. This clinical report reviews the principles involved in the clinical indication for an overlay RPD, as well as the necessary planning and execution, to discuss the feasibility and clinical effectiveness of this treatment, identifying the indications, advantages, and disadvantages of this procedure through the presentation of a clinical case. The overlay RPD can be an alternative treatment for special situations involving partially edentulous arches in patients who need reestablishment of the OVD and/or realignment of the occlusal plane, and it can be used as a temporary or definitive treatment. The main advantages of this type of treatment are its simplicity, reversibility, and relatively low cost; however, further studies are needed to ensure the efficacy of this treatment option.     

Force Finishing and Centering to Balance a Removable Complete Denture Prosthesis Using the T-Scan III Computerized Occlusal Analysis System

Obtaining bilateral balance of removable complete denture prostheses is the occlusal goal of the restorative dentist or prosthodontist. Despite our best clinical efforts, and the using of advanced mechanical devices like semi-adjustable articulators and face bow transfer mounting of dental casts, it is a struggle to provide accurate occlusal force balance. Some of the advocated reasons for the clinical difficulty of obtaining reliable occlusal balance are that stone casts lack soft tissue resiliency, and articulators only approximate human occlusal functional movements. However, modern technology offers clinicians a digital answer to this clinical force balance problem. It is known as computerized occlusal analysis. The T-Scan III system can be employed with complete removable denture prostheses to perform computer-guided occlusal force-finishing corrective adjustments that measurably improve the installed prosthetic occlusal balance.     

Repair of a Removable Partial Denture Using Gold Occlusals

Limited interarch space causes maintenance problems with removable partial dentures. The problem of abrasion and breakage of acrylic resin teeth, the concomitant supraeruption of opposing natural teeth, and possible decrease of vertical dimension of occlusion can be prevented or minimized with cast-gold occlusals. Use of metal occlusals has been advocated on newly constructed removable partial dentures, but not on existing prostheses with severely worn or broken denture teeth. This article describes a repair procedure for a removable partial denture where minimal interarch distance resulted in wear and breakage of denture teeth. A thin, abraded denture tooth that had been repaired numerous times was prepared and covered with a cast gold restoration. The problem of abrasion and breakage of the acrylic resin tooth was solved and the service life of the prosthesis was extended.     

CAD/CAM Constructed Poly(etheretherketone) (PEEK) Framework of Kennedy Class I Removable Partial Denture: A Clinical Report

The prevalence of partially edentulous adults that could be treated by removable partial dentures (RPDs) is estimated to be greater than 20% in some regions of the United States. Problems related to traditional materials for RPD construction have been documented. Advances in polymer‐based materials and digital fabrication strategies would allow increased biocompatibility, durability, and elasticity, as well as more esthetically pleasing and cost‐effective benefits. This article reports on poly(etheretherketone) RPD framework produced by digital and milling technology.     

The Use of CAD/CAM Technology for Fabricating Cast Gold Survey Crowns under Existing Partial Removable Dental Prosthesis. A Clinical Report

The fabrication of a survey crown under an existing partial removable dental prosthesis (PRDP) has always been a challenge to many dental practitioners. This clinical report presents a technique for fabricating accurate cast gold survey crowns to fit existing PRDPs using CAD/CAM technology. The report describes a technique that would digitally scan the coronal anatomy of a cast gold survey crown and an abutment tooth under existing PRDPs planned for restoration, prior to any preparation. The information is stored in the digital software where all the coronal anatomical details are preserved without any modifications. The scanned designs are then applied to the scanned teeth preparations, sent to the milling machine and milled into full‐contour clear acrylic resin burn‐out patterns. The acrylic resin patterns are tried in the patient's mouth the same day to verify the full seating of the PRDP components. The patterns are then invested and cast into gold crowns and cemented in the conventional manner.     

Fabrication of a New Crown and Provisional to an Existing Removable Partial Denture

A method of fabricating a new crown to an existing removable partial denture is described. A press-form plastic shell made from the diagnostic cast provides the outer contours for the abutment tooth, while an acrylic resin coping is fabricated on a die to provide accurate internal adaptation. The acrylic resin coping is seated on the prepared abutment. Autopolymerizing acrylic resin is mixed and placed in the plastic shell that is then placed in the mouth over the coping, forming the acrylic resin crown pattern. The removable partial prosthesis is fitted over the crown pattern intraorally. The pattern is transferred back to the die, the margins are refined, and the casting is completed and finished, avoiding reduction of the established contours. The same plastic shell is used with tooth-shaded acrylic resin to construct a provisional crown directly in the mouth. This technique allows the patient to wear the removable partial denture while the laboratory procedures are completed.     

Wear Testing of Composite, Gold, Porcelain, and Enamel Opposing a Removable Cobalt–Chromium Partial Denture Alloy

Purpose: Eighty percent of all removable partial denture (RPD) frameworks are fabricated from cobalt–chromium (Co–Cr) alloys. The advantages of this material include low density and high modulus of elasticity, hardness, and strength. Hardness is of particular concern when related to excessive wear of natural teeth or restorative materials. The purpose of this study was to compare the differences in localized wear among enamel, composite, gold, and porcelain by a Co–Cr alloy RPD.
Materials and Methods: Thirty-two polished specimens were prepared and positioned in an acrylic-filled custom fixture for testing. Upon optical examination, the highly polished surfaces of the specimens were scratch-free. They were mounted into a water bath fixture and subjected to 250,000 cycles in a wear simulator equipped with a conical Co–Cr stylus specially fabricated to produce localized wear. A posttest was generated, and the profiles were fitted and evaluated using software. The total volume loss and depth of the wear facet on each specimen were analyzed using ANOVA and Fisher's PLSD test.
Results: Volume loss (mm³) was as follows: composite, 0.110; gold, 0.021; enamel, 0.008; porcelain, 0.006. The maximum depths (μm) were: composite, 92; gold, 22; enamel, 13; porcelain, 17. Resin composite had significantly higher values ( p < 0.0001) of volumetric loss and maximum depth than the other materials. No significant differences were detected among volumetric loss and maximum depth values for gold, enamel, and porcelain.
Conclusions: Significant differences for mean wear volume loss and maximum depth were found between composite and gold, enamel, and porcelain. Enamel proved to be wear resistant to the Co–Cr alloy. Clinical implications: porcelain and gold appear to be good options for occlusal surfaces opposing a Co–Cr alloy; however, the test composite was not found to be a recommended option.     

Dual Path: A Concept to Improve the Esthetic Replacement of Missing Anterior Teeth with a Removable Partial Denture

The dual path of insertion concept for removable partial denture (RPD) design may be used in esthetically demanding situations. When compared to conventional RPDs, the main advantage of this design is the minimal use of clasps. This clinical report describes the treatment of a patient with an anterior maxillary edentulous area using a dual path RPD. The diagnostic cast was surveyed to ensure the adequacy of the undercuts on the mesial surfaces of the anterior abutments, where rigid minor connectors were placed. Inverted V‐shaped canine cingulum rest seats were prepared to provide resistance to tooth movement during function. The dual path RPD concept allows excellent esthetic results, minimizes tooth preparation, and reduces the tendency toward plaque accumulation in a Kennedy class IV partially edentulous arch.