Slide 1: Assalamaa aleh kum Relining of Removable Partial Dentures : Relining of Removable Partial Dentures Prof. Dr. S. Venugopal. Indications for relining a distal extension RPD : Indications for relining a distal extension RPD Loss of tissue support that causes rotation and settling of the distal extension base.
Loss of occlusal contact causing difficulty in mastication The need for relining a distal extension base is detected by : The need for relining a distal extension base is detected by By applying pressure on the extreme distal end of the denture base and watching the anterior indirect retainer as it lifts off.
Loss of occlusal contact is detected by having the patient close on two strips of blue casting wax. If the occlusal contact between the artificial dentition is weak or lacking; while natural teeth in opposition are making firm contact, then the RPD needs relining. The need for relining a bounded case of a RPD is detected by : The need for relining a bounded case of a RPD is detected by Unpleasant appearance, due to space that may develop between the denture base and underlying tissues.
Lack of tissue contact and patient’s discomfort.
Entrapment of food debris. I. Laboratory Relining : I. Laboratory Relining Closed mouth technique: in bounded cases
Open mouth technique : in distal extension cases Closed mouth technique : Closed mouth technique Procedure:
The tissue surface of the denture base is relieved to accommodate the impression material.
The impression material is mixed and applied to the tissue surface and the PD is seated in the patient’s mouth making sure that the impression material is kept away from the occlusal rests.
The patient is asked to close in centric occlusion until complete setting of the material.
An overall alginate impression is made, cast poured, then the RPD is flasked, processed and reline material is added. Open mouth technique : Open mouth technique functional reline impression technique II. Intra-oral (chair side) relining : II. Intra-oral (chair side) relining Advantages
The patient does not leave his denture.
After relining occlusal corrections should be done. If minor adjustments are required it could be carried out intraorally. However, occlusal adjustments for distal extension PDs may be accomplished more accurately by remounting procedures. Removable Partial Overdentures : Removable Partial Overdentures Prof. Dr. S. Venugopal. Definition : Definition It is a removable prosthesis that is retained and supported by some of the natural teeth or roots under its base. If the natural roots or teeth are replaced by an implant it is called an implant supported partial denture Indications : Indications In cases where the chosen abutment teeth show improper crown/root ratio, so reduction of the natural crown is done to improve the C/R ratio.
In cases that provide poor prognosis if restored by conventional removable partial denture; for example:
Few remaining natural teeth.
Remaining healthy roots.
Long span, edentulous ridge.
A case contra-indicated for fixed partial denture Indications : Indications Excessive wear of the teeth, which may result from erosion, abrasion or attrition
Loose teeth that can be devitalized and reduced in favor of C/R ratio and their presence maintain the level of alveolar bone.
Patients with congenital defects are cosmetically and functionally inadequate as regards dental and alveolar arch relationships. Removable partial overdenture gives excellent (superb) results. Contraindications : Contraindications When other prosthesis give and provide superior and efficient and more beneficial results.
In cases of bad oral hygiene, where the patient can't afford the least routine ways, that keeps and maintains the health of the remaining natural teeth.
When the interarch space is insufficient. Advantages : Advantages Good stability as its support is mainly from the teeth rather than the edentulous ridge.
Provides more load distribution, which minimizes the trauma of soft tissues and bone resorption.
It needs minimum adjustment and modification, as it is highly supported and stable.
Preservation of proprioceptors in the periodontal membrane of the remaining roots, so the jaw relation will be easily recorded.
Easily accepted and used, so the patient is satisfied and feels normal especially during mastication. Disadvantages : Disadvantages It can interfere with the inter-arch space, as it is more bulky (especially if not perfectly constructed).
More time consuming and more expensive.
Needs more clinical and laboratory steps. Attachments in Removable partial overdentures : Attachments in Removable partial overdentures Increases retention, stability and support.
Distribution of masticatory load between abutment and tissues.
Splinting of questionable abutments Implant supported Removable partial Overdentures : Implant supported Removable partial Overdentures Indications
Partially edentulous cases with unilateral or bilateral free end saddle cases.
Long span cases with few remaining teeth.
To help periodontally involved teeth.
In cases of resected mandible. Repair of Removable Partial Dentures : Repair of Removable Partial Dentures Prof. Dr. S. Venugopal. Broken clasp arm : Broken clasp arm It may be replaced by wrought wire clasp embedded in the resin or attached to the metal base by soldering.
In cases where a rigid clasp is needed a new clasp assembly may be cast and attached to the framework by soldering Broken occlusal rest : Broken occlusal rest A new clasp assembly is made and soldered to the denture framework. Addition of a new tooth : Addition of a new tooth In cases where the last tooth is an abutment supporting a clasp arm:
Cut off the clasp arm and prepare the adjacent tooth to receive the new clasp. Cast the new clasp and attach it to the framework by soldering, then add the artificial tooth to replace the lost natural tooth. Addition of a new tooth : Addition of a new tooth If the lost tooth is not the main abutment:
If the denture base is resin simply make retentive means in the acrylic resin and add the tooth. If the denture base is metal, this necessitates both casting a new component and attaching it by soldering or creating retentive means for the attachment of an acrylic resin extension. Slide 24: THANK YOU My sir… with your preaching I am here and sharing the knowledge with the world of new dental doctors…