RELINING, REBASING AND REPAIR Flashcards
Why is important RELINING? And what is it?
Relining requires less number of appointments and is often indicated for economic reasons. Though it is not an easy procedure, it is an essential part of complete denture treatment.
The process of adding some material to the tissue side of a denture to fill the space between the tissue and the denture base to improve the fit of the denture (Winkler).
What are indications of Relining?
Indications
- Changes in the denture bearing area (due to resorption). Usually, these changes may present as
a. Loss of retention and stability
b. Loss of vertical dimension
c. Loss of support for facial tissues
d. Incorrect occlusal relationship (can cause shifting of the dentures)
e. Reorientation of occlusal plane
Note When the above changes are severe, rebasing is indicated, instead of relining.
- Immediate denture at 3 to 6 months after the original construction.
- Socioeconomic condition - when a patient cannot afford new dentures.
- Geriatric or chronically ill patients who cannot take the stress of too many appointments.
- Patients who for some reason cannot come for the multiple appointments required for a new denture.
- A new denture which does not have the expected fit at the time of delivery.
What are contra indications of Relinin?
- When the denture base itself is in poor condition or of poor quality.
- Too much resorption.
- Abused oral tissues (tissues should be allowed to recover).
- Temperomandibular joint problems (it should be treated first).
- Poor teeth arrangement (poor esthetics).
- Unsatisfactory jaw relationship.
- Severe bony undercuts (defer until surgical removal and healing).
- Major speech problems.
What are Relining materials and techniques
- Relining with autopolymerizing acrylic resin.
- Relining with permanent soft liners.
- Relining with tissue conditioning material (temporary soft liner).
Talk about tissue preparation in Relining
The tissue must be in a healthy state prior to making the impression. The following procedures may be done to improve the tissue foundation.
- Hypertrophic tissues are removed surgically.
- Dentures are left out of the mouth 2 to 3 days before making the final impression.
- Daily massage of the tissue.
- Use of tissue conditioners.
Talk about denture preparation in Relining
- Pressure areas are relieved.
- Occlusal disharmonies are corrected.
- Large undercuts are relieved.
- The tissue side is relieved by 1.5 to 2 mm.
- The denture periphery is shortened to create a flat border.
What are classification of Impression techniques in relining
- Static impression techniques
- Closed mouth impression
- Open mouth impression.
- Functional impression techniques
- Using a tissue conditioner.
Talk about open mouth techniques in relining and its dis advantage
The dentures are used as impression trays and both maxillary and mandibular dentures are relined at the same sitting.
- A posterior palatal seal is formed in modeling compound
- The borders are shortened and 1 mm of space is provided on the tissue side by trimming with a bur
- A modeling compound handle is attached for the lower denture
- Adhesive tape is placed over the polished surfaces.
- Border molding is done with green stick compound.
- Final impressions are made with zinc oxide eugenol or elastomers.
- A centric record is made using the impressions as record bases.
Disadvantages
- It is demanding and laborious.
- It needs more chair and laboratory time.
Talk a bout FUNCTIONAL IMPRESSION TECHNIQUE WITH TISSUE CONDITIONER
Tissue conditioner (temporary soft liner) can be used to line the denture and bring the tissues back to health. Tissue conditioner can also be used as a functional impression material.
§ In this technique the existing intercuspation is used to stabilize the dentures.
§ Centric records are made first using compound or wax.
§ The denture preparation is similar.
§ Border molding is done wherever flanges are under extended.
§ The tissue conditioner is placed, the excess trimmed and the patient is dismissed.
§ After 3 to 5 days, the denture is examined for denuded areas, which if present are marked and relieved. The tissue conditioner is then reapplied
§ The patient is reviewed periodically and the material renewed until the tissues return to health. § Final impression - the old tissue conditioner is removed and replaced with the new material
§ The patient is asked to wear it for 30 minutes. A light meal may be eaten if desired. It is then
removed and a cast is poured immediately.
LABORATORY PROCEDURES for rebasing and refining?
There are many methods of relining a denture in the laboratory. These include
- Articulator method
- Jig method
- Flask method
Talk about CHAIRSIDE RELINE TECHNIQUE
everal materials have been marketed which can be used to reline the dentures directly in the patients mouth (fig. 21-1. A and B).
These have not been successful due to
- Chemical burns (from the monomer).
- Porosity and poor odor.
- Poor color stability.
- Material cannot be removed easily if there is any mistake.
Chair side relining is not recommended because of the above drawbacks.
Define rebasing and its indications
The process of replacing all the base material of a denture without changing the occlusal relationship (Winkler).
INDICATIONS
- It is done if the observed clinical changes are moderate to maximal.
- When the denture base has to be changed due to some processing defects e.g., due to discoloration, porosity etc.
- Denture teeth should be in a good condition.
- When porcelain teeth have been used.
