Extracoronal Attachments Research Articles

An alternative procedure for positioning a prefabricated extracoronal attachment in a removable partial denture

An alternative procedure for positioning a prefabricated extracoronal attachment in a removable partial denture

Three‐dimensional finite element analysis of the application of attachment for obturator framework in unilateral maxillary defect

The aim of this study was to evaluate the stress on the abutment teeth and framework ina unilateral maxillary defect which was restored by an obturator retained by resin-bonded extra coronal attachment. A three-dimensional finite element model of the human unilateral maxillary defect was constructed. Traditional obturator framework with four casting circumferential clasp was established (model 1). A continuous lingual guide plane of 0.5 mm thickness on all of the remaining teeth, with Mini-SG/F attachment on the mesial surface of the central incisor was also established (model 2). The modelling and analytical processes were performed using the ANSYS technologies. Stress was transmitted to the anterior part of the palate, with stress values being lower on the anterior teeth compared with the posteriors. The highest stress value of model 1 and model 2 was 13.1 Mpa, 19.9 Mpa respectively. Stress concentrations were found at the junction of the attachment to the lingual guide plane and the anterior part of the lingual plane. The results of this study suggest that the application of a resin-bonded extra coronal attachment for obturator retention is in accordance with the design principles for the restorative treatment of maxillary defects.The design of the attachment framework needs to be further investigated. Benefit can be gained by splinting the abutment teeth.

A simple method to improve the retention of an extracoronal resilient attachment

A simple method to improve the retention of an extracoronal resilient attachment

下顎両側遊離端症例に対し歯冠内および歯冠外磁性アタッチメントを応用したパーシャルデンチャーの1例

下顎両側遊離端症例に対し歯冠内および歯冠外磁性アタッチメントを応用したパーシャルデンチャーの1例

10. 両側遊離端症例に対し磁性アタッチメントを応用したパーシャルデンチャーの一例(口頭発表,第66回九州歯科学会総会講演抄録)

10. 両側遊離端症例に対し磁性アタッチメントを応用したパーシャルデンチャーの一例(口頭発表,第66回九州歯科学会総会講演抄録)

Alternative method for connecting a removable gingival extension and fixed partial denture: A clinical report

In terms of esthetics and hygiene, defects in the alveolar ridge can complicate the design and fabrication of fixed partial dentures. When missing anterior teeth are restored, it may be difficult to achieve a satisfactory appearance without the correction of soft tissue and alveolar defects. When surgical intervention is not an option, a removable gingival extension and fixed prosthesis may be considered. This clinical report describes the use of a custom-made pin system (rather than intra- or extra-coronal attachments) to esthetically connect a removable gingival extension to a fixed partial denture. (J Prosthet Dent 2002;88:1-3.)

Custom precision attachment housings for removable partial dentures

<h2>Abstract</h2> 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. <b>(J Prosthet Dent 2002;88:100-2.)</b>

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. (J Prosthet Dent 2002;88:100-2.)

Clinical performance of resin-bonded fixed partial dentures and extracoronal attachments for removable prostheses

Statement of problem. It is important to evaluate the long-term clinical performance of resin-bonded fixed partial dentures and extracoronal attachments for removable prostheses.Purpose. A prospective, long-term clinical study was conducted to evaluate the success of resin-bonded fixed partial dentures since 1985 and of resin-bonded extracoronal attachments from 1987.Methods. Until 1993, a total of 130 resin-bonded fixed partial dentures had been seated in 101 patients, as well as 12 removable partial dentures (RPDs) with 24 extracoronal retainers in 10 patients. The clinical treatment protocol and the laboratory procedures were standardized. By the end of 1993, it was possible to reexamine 98 patients with a total of 127 resin-bonded fixed partial dentures and all 10 patients with removable partial dentures. The average time in function for the resin-bonded fixed partial dentures at the time of examination was 3.4 years and 2.3 years for the removable restorations.Results. During the period of observation, one retainer failed on six of the resin-bonded fixed partial dentures, which represents a failure rate of 4.7%. Debonding of extracoronal attachments was recorded for 8.3% of the total number of retainers.Conclusion. The resin-bonded fixed partial denture technique can be considered to be a clinically reliable method of treatment, and permits the expansion of indications beyond a classical three-unit resin-bonded fixed partial denture. Long-term clinical success of removable partial dentures with resin-bonded extracoronal retainers warrants additional clinical studies. (J Prosthet Dent 1997;78:465-71.)

Effect of splinting on load distribution of extracoronal attachment with distal extension prosthesis in vitro

Previous reports have suggested that the restoration of distal extension edentulous areas with an extracoronal precision attachment partial denture necessitates splinting of abutments. However, the number of splinted teeth remains controversial. In this study, strain gauge technology was used to monitor stresses induced around the abutment and in the distal extension area under different loads as a function of the number of splinted abutments. Three strain gauges were installed in the outer buccal, lingual, and distal surfaces of the abutment to record stresses in the three planes of motion, and another gauge was placed under the distal extension base. The reduction of the number of splinted units from three to two resulted in an insignificant increase of stresses recorded, whereas reduction of the number from two to one resulted in a significant increase of stresses nine times greater than the three-unit splint values. On the basis of this in vitro model, at least two teeth on each side should be splinted when extracoronal distal extension attachment prostheses are used.

Parallel bonded cast attachments for removable partial dentures

The original design of a semi-precision extra-coronal attachment for partial dentures is illustrated, and its fabrication in a cast non-precious bondable alloy is described. A step-by-step method is also described of bonding multiple attachments in parallel for the retention and support of removable partial dentures. Clinical cases are illustrated. The results of trials indicate that the method is clinically viable and, in selected cases, appears to offer distinct advantages over existing retention systems.

Load transfer by a maxillary distal-extension removable partial denture with cap and ring extracoronal attachments

This study photoelastically compared the stress distribution characteristics of maxillary, bilateral, distal-extension removable partial dentures retained by light and heavy ERA extracoronal attachments. One prosthesis included supporting rests and the other had no rests. Both designs were tested with and without abutment splinting. The most favorable stress distributions were obtained with light retention elements, supporting rests, and splinting of the abutments. In this configuration the attachment prosthesis compared favorably in stress distribution with the maxillary I-bar retained removable partial denture in a previous study that used a comparable maxillae model.

Resin-bonded etched castings with extracoronal attachments for removable partial dentures

An innovative method of using resin-bonded etched cast extracoronal attachments as an esthetic alternative in removable prosthodontics is presented. The technique is simple, conservative, inexpensive, and not time-consuming. The steps of abutment teeth preparation, casting of a precise framework, and cementation are technique-sensitive, and short cuts are not well tolerated. The existing clinical results indicate that the technique is a valuable adjunct in the field of esthetic removable partial prosthodontics.

Book Reviews

Book reviewed in this article:ESSENTIALS OF DENTAL SURGERY AND PATHOLOGY, by R. A. CawsonTHE DENTAL OFFICE. A PICTORIAL HISTORY, by Richard A. GlennerABNORMAL JAW MECHANICS. DIAGNOSIS AND TREATMENT, edited by W. K. Solberg, and G. T. ClarkTHE KURER ANCHOR SYSTEM, by Peter F. KurerENDODOTICS, by E. NichollsCOMPLETE DENTURE PROSTHETICS. A CLINICAL AND LABORATORY MANUAL, by D. J. Neil, and R. I. NairnSYSTEMIC DISEASE FOR DENTAL STUDENTS, by T. J. Bayley, and S. J. LeinsterA HANDBOOK FOR CLINICAL TEACHERS, by D. Newble and R. CannonA GUIDE TO SUCCESSFUL DENTAL PRACTICE, by J. O. ForrestIMPRESSIONS FOR COMPLETE DENTURES, by Bernard LevinCLINICAL MANAGEMENT OF CHILD ABUSE AND NEGLECT, by R. G. Sanger, and D. C. BrossPRECISION ATTACHMENTS IN PROSTHODONTICS: THE APPLICATIONS OF INTRACORONAL AND EXTRACORONAL ATTACHMENTS, by H. W. Preiskel

Extracoronal Attachments

An overview of several types of extracoronal attachments has been presented. They have been classified into rigid types, resilient types, and bar attachments. The uses of each classification were discussed, and the problems inherent with all types of extracoronal attachments were mentioned.

Occlusal force transmission by overdenture attachments

This investigation utilized a composite photoelastic model to examine the load-transfer characteristics of several overdenture attachments. Tissue bar (Hader and King Connector) and stud (extracoronal) attachments (Rotherman, Gerber, and Ancrofix) were studied. The following observations may provide guidelines for the selection of overdenture attachments. 1. The more retentive tissue bar and extracoronal attachments produced higher stress concentrations. 2. Of the tissue bars tested, the Hader Bar produced less torquing forces on the abutment teeth. 3. The Ancrofix appeared to share the forces of occlusion between abutments and the posterior edentulous regions. 4. It must be emphasized that several other factors will also influence the choice of overdenture attachments, such as the judgment of the dentist, economics with respect to the patient, and the availability of laboratory expertise.

A retentive attachment for overdentures

A technique is described that incorporates an extracoronal attachment within an overdenture to provide increased retention. This type of retentive attachment is easily fabricated. It's durability, simplicity, adjustability, and adaptability to a wide variety of situations make it most useful. The retentive attachment may be used with either removable partial dentures or complete dentures.

Ceka extracoronal attachments

Summary Many precision attachments are available for use with removable restorations. The Ceka extracoronal attachment is described in this article. The economy, simplicity of care, ease of insertion and removal, and comfort in function make this type of prosthesis acceptable to patients. The ease of fabrication, esthetics, and strength make the Ceka attachment a necessary adjunct to the armamentarium of modern prosthetic dentistry.

The cingulum clasp

The cingulum clasp can be used as a retainer on cuspid teeth when other extracoronal attachments are esthetically unacceptable. The principles of its design are described.