Biomedical subjects

James S Brudvik

Publications and source records attributed to James S Brudvik.

7 recordsLinked to original sources

PubMed2006

A clinical investigation of the fit of removable partial dental prosthesis clasp assemblies.

STATEMENT OF PROBLEM: Removable partial denture frameworks are complex castings fabricated from high-shrinkage alloys. This may result in difficulty in achieving accurate fit. PURPOSE: The purpose of this study was to evaluate which component(s) of the clasp assembly contact the abutment tooth clinically. MATERIAL AND METHODS: New and existing frameworks with at least 1 conventional prepared occlusal rest were evaluated for fit. The spacing between the bottom of each of the rests of the 50 clasp assemblies and the corresponding rest seat were recorded with vinyl polysiloxane. The fit of each rest was determined with the use of a dial caliper by measuring, in micrometers, the thickness of the record between the rest and the bottom of the rest seat. The Kennedy classification was also recorded. A 2-sample t test was used to evaluate the difference in fit between tooth-tissue supported and tooth-supported designs (alpha=.05). RESULTS: The average space between the rest and prepared rest seat was 193 +/- 203 microm, with a range of 0 to 828 mum. Twenty tooth-tissue frameworks had an average space of 136 +/- 160 microm and 30 tooth-supported frameworks had an average space of 230 +/- 222 microm. The 2-sample t test showed no significant difference for fit between tooth-tissue supported and tooth-supported frameworks (P=.1081). Twenty-four percent of rests had contact in the prepared rest seat. CONCLUSION: The majority of rests evaluated did not contact the intended surfaces.

Dental Abutments↗

PubMed2004

The milled surface as a precision attachment.

The creation of paralleled, milled surfaces in natural or restored abutment teeth, coupled with removable partial denture castings that have optimal contact with these preparations, results in a path of insertion and removal that is controlled in a manner similar to one using conventional precision attachments. Because the milled surfaces are primarily extracoronal, little if any, additional tooth reduction is required for adequate mouth preparation. Avoiding additional tooth reduction minimizes later abutment fracture. The great increase in stability and resistance to rotational movements, when combined with conventional posterior clasping, provides a reasonable alternative to the precision attachment in providing maximal esthetics for the partially edentulous patients.

Dental Abutments↗

PubMed2004

The conversion partial denture: a clinical report.

The treatment alternative described maximizes the benefit of remaining teeth while allowing simplified alteration of the prosthesis if abutments are lost during the life span of the removable partial denture (RPD). A conversion partial is an RPD whose tooth-frame assembly components are individually fabricated and then joined with an acrylic resin major connector. The conversion RPD optimizes retention and stabilization of a terminal dentition and can be easily converted to an immediate complete denture.

Aged↗

PubMed2004

Clinical outcome of the altered cast impression procedure compared with use of a one-piece cast.

STATEMENT OF THE PROBLEM: An altered cast impression procedure to improve the support of distal extension removable partial dentures is widely taught, but not often used in dental practice. PURPOSE: The purpose of this study was to determine the efficacy of an altered cast compared to a one-piece cast with regard to base support, abutment health, and patient comfort over time. MATERIAL AND METHODS: Seventy-two patients receiving a mandibular bilateral distal extension removable partial denture were assigned randomly for treatment using either a one-piece or an altered cast. All impressions and associated laboratory procedures were made by one investigator. A second investigator evaluated extension, support, and adaptation of the denture bases by observation of border length and lifting of the indirect retainer from its seat. The space between the soft tissues and the base when the framework was related to the teeth was measured cross-sectionally at half the length of the denture base. Mobility, gingival index, and sulcus depths at 6 locations around each abutment tooth were recorded at insertion and again 1 year later. Chi-square tests were used to evaluate differences between the treatment groups (alpha=.05). RESULTS: There was 0.15 mm less space between the ridge crest and base in the altered cast group (P<.01), and underextension of the base occurred only in the one-piece cast group (P=.01). At insertion, no tissue-ward movement was observed in 85% of the prostheses when anterior-posterior rotation was attempted. Fifteen subjects (21%) were lost to recall at 1 year, but they were distributed equally between the 2 groups. Of the remaining 57 prostheses, 42% exhibited decreased base support and 33% had increased gingival inflammation; the deepest probing depth decreased in 61%, mobility decreased or remained the same in 80% of the direct abutments, and 88% of the subjects were satisfied. None of these findings were related to the impression procedure. CONCLUSION: The altered cast impression procedure does not offer significant advantages over the one-piece cast, provided the standards used in this study are met. These include a completely extended impression, use of magnification to adjust and ensure complete seating of the framework, and coverage of the retromolar pad and buccal shelf by the base.

Adult↗

PubMed2003

Posterior implants for distal extension removable prostheses: a retrospective study.

Common complaints associated with the Kennedy Class I (bilateral free end) and Class II (unilateral free end) removable partial denture situations are lack of stability, minimal retention, and unesthetic retentive clasping. Some of the same complaints have been reported for implant overdentures with only anterior implants. Starting in 1995, 10 of these patients were treated at the University of Washington with posterior osseointegrated implants to provide stability and/or retention of the removable prostheses, eliminating the need for clasps when possible. This article describes implant alternatives and prosthesis designs and presents a follow-up clinical evaluation of at least 1 year consisting of patient satisfaction, radiographic examination, and soft tissue health. Two groups were evaluated. Group 1 included patients whose implants were used as vertical stops for mandibular distal extension prostheses. Care was taken to ensure that the implants were not loaded laterally by creating a single-point contact at the center of a modified healing abutment. In these cases, sufficient retention was available from the anterior teeth and/or implant abutments. Group 2 included patients whose implants required retention because of lack of adequate tooth abutments. In those cases, a resilient type of attachment was used, which allowed for a small divergence from the path of insertion. Results indicated consistent increased satisfaction in all patients, minimal component wear, no radiographic evidence of excessive bone loss, and stable peri-implant soft tissues.

Aged↗

PubMed2002

Custom precision attachment housings for removable partial dentures.

Limited space for extracoronal attachments is a serious complication in the design and fabrication of a precision attachment removable partial denture. A custom metal-ceramic housing joined to the partial framework with laser welding offers strength and improved esthetics while requiring minimal space. This article presents the technical aspects of custom housing construction.

Dental Soldering↗

PubMed2002

The milled implant bar: an alternative to spark erosion.

Patients who cannot tolerate total coverage of the hard palate or whose maxillary arches are poorly formed, because of congenital, developmental or surgical defects, may be unable to wear a conventional complete denture. These patients can be successfully treated with implant-supported prostheses that cover only a minimal amount of palatal tissue. With spark-eroded castings, very precise restorations can be constructed to fit such implant supports. However, these castings are so expensive that cost precludes their use for many patients. This article presents an alternative approach, developed with the refined techniques used for removable partial dentures, which can yield results similar to those for spark-eroded castings at a fraction of the cost. The clinical and laboratory procedures involved in this technique are described.

Dental Casting Technique↗