The document discusses relining and rebasing of dentures. Relining involves resurfacing the tissue side of a denture with new base material to improve adaptation, while rebasing replaces the entire denture base. The main objectives are to re-establish correct denture-tissue relationship and restore stability, retention, and occlusion. Common indications include alveolar resorption, decreased vertical dimension, and immediate dentures. Contraindications include excessive ridge resorption and poor jaw relations. Clinical procedures involve tissue and denture preparation before making new impressions, while laboratory procedures include articulation, reverse flasking, and jig methods.

1. Relining and Rebasing
Final Year BDS
31 – 05 - 2012

2. Relining
The procedure used to resurface the tissue side
of a denture with new base material, thus
producing an accurate adaptation to the denture
foundation area.
Or
Relining is the procedure used to resurface the
tissue side of a denture with new base material.
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3. Rebasing
Rebasing is a process of replacing all the base
material of a denture. Only the original teeth and
their arrangement remain.
Or
The laboratory process of replacing the entire
denture base of an existing prosthesis.
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4. Objectives
The main objectives of relining or rebasing are to:
 Re-establish the correct relation of the
denture to basal tissue.
 Restore stability and retention
 Restore lost occlusal and maxillo-mandibular
relationship.
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5. Common Indications for
Relining and Rebasing
 Imperfection in the denture base
 Defects in the impression surface of the
denture due to
 Improper handling of the tissues during
impression making.
 Processing defects

Porosities, shrinkage/contraction, gaseous, gr
anular.
 Warpage/crazing of the material
 Defects in the polished surface
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6. Common Indications for
Relining and Rebasing
 Alveolar resorption
 Continued resorption of the residual alveolar ridge
under the complete denture.
 Decreased occlusal vertical dimension
 Due to faulty techniques
 Immediate dentures
 Regular periodic relines are required
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7. Common Indications for
Relining and Rebasing
 Socioeconomic constraints
 New denture costs are unaffordable
 Physical/ mental state of the patient.
 Chronically ill patients
 Geriatrics
 Mentally compromised individuals
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8. Contraindications
 Excessive resorption of the alveolar ridge
 Highly inflamed/ abused soft tissues
 Poor, unacceptable esthetics
 TMJ problems
 Unsatisfactory jaw relation
 Horizontal, vertical and orientation relations
 Severe osseous undercuts which require
surgical correction
 Severe speech problems
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9. General Complaints
After a period of successful denture wear the patient
complains of
 Looseness
 Ill-fitting dentures with loss of stability and
retention
 General soreness and inflammation
 Chewing inefficiency over a period of time
 Aesthetic problems.
 Decreased chin nose distance
 Prominence of chin
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10. Selection of the patient
 Satisfactory OVD
 CO should coincide with CR.
 Satisfactory esthetics
 Healthy oral tissues
 Adequate denture base extensions
 Adequate load distribution on the basal seat
 Satisfactory speech
 Suitable/healthy soft tissues with out undercuts
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11. Materials
1. PMMA
• Heat cured acrylic resin
• Cold cured acrylic resin
2. Modifications of PMMA
• Butyl meth acrylate
3. Soft liners/ tissue conditioners
• Plasticized acrylic resin
• Chemically activated…. short term denture liners
• Heat activated…. long term denture liners
• Vinyl resins
• Silicone materials
 Chemically activated
 Heat activated
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12. Techniques
 Clinical procedures
 Laboratory procedures
 Chair side relining technique
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13. Clinical procedures:
The clinical procedures for both relining and
rebasing can be achieved by the use of one of the
following methods:
The static impression technique.
The functional impression technique.
The clinical procedures of relining and rebasing
includes both tissue and denture preparations.

14. 1.Tissue Preparation:
Tissue Rest:
1. Instruct the patient to leave the old dentures
out of the mouth at least 8 hours preferably
at night.
2. The dentures should be left out of the mouth
at least two to three days before making the
final impression.
3. Massage of the soft tissues two or three
times a day to stimulate the blood supply
and aid recovery.

15. B) Use of Tissue Conditioner
1. Extensive tissue abuse
2. Pt. cannot leave the dentures out for tissue
recovery.
3. Transmission of masticatory forces to the
supporting mucosa are equalized by eliminating
isolated pressure spots typical of a loose, ill
fitting denture.
4. The material is renewed periodically every 3 to
7 days.
5. When the tissues had returned to a clinically
discernible healthy state, the patient is
scheduled for making the impression.

16. c) Surgical management:
Excessive hypertrophic tissue should be surgically
removed. The denture can be used as a surgical
splint.

17. Denture Preparation
1. Balanced occlusion to ensure that uneven
contact does not bring about a bodily shift
or tilt of the denture when the patient is
asked to close together.
2. Reduction of sharp and overextended
borders.
3. Pressure areas in the tissue surface of the
dentures should be relieved.

18. Clinical procedures
 Preparation for the impression
 Adjustment of occlusion
 Jaw relation records
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19. Laboratory procedures
 Articulation method
 Reverse flasking method
 Jig method
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