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Duplication of Dentures can be done by the Simple Duplication Technique.

Describe this Technique

*This is a partial copy technique.

Silicone putty is used to create model of the old denture rather than using a conventional intraoral impression with alginate.

The lab can then use the putty to prepare a model and special tray to take a definitive secondary impression.

Alma Gauge readings are then provided to the lab to aid fabrication of the registration rims.

-What are the 7 key stages of the Complex Duplication Technique

*First Assess if the Current Denture is suitable for Duplication before embarking

1) Make a negative of the dentures in an alginate flask

2) Template in Wax & Acrylic

3) Make any adjustments to the face height

4) Remove Wax Teeth and Replace with Acrylic Teeth

5) Try in and Reline Impressions

6) Process & Finish

7) Placement and Check Record

-When you trim the Alginate, what dimension do you trim it to

*Ensure the Alginate is trimmed to within 2mm of the peripheral border seal

-What are Immediate Dentures

*An immediate denture is a prosthesis that is fitted immediately after the extraction or modification of teeth. It replaces the missing teeth and where required, the adjacent hard and soft tissues.

-What factors need to be considered when assessing a patient for immediate dentures (4)

*1) Does the patient have a current partial denture which can be added to and used as a transitional denture

2) Does the patient have a history of nausea, if so, a denture may not be tolerated if the patient has a strong gag reflex

3) Can the extractions be phased, removing teeth in the non-aesthetic zones first, allowing bone to remodel before re-embarking on a denture

4) Undercuts - is surgery required. Most common due to caries

-What are the indications for Immediate Dentures (4)

*1) When Remaining Teeth are a Health Risk i.e. Infection, Radiotherapy

2) When Fewer Visits are Essential i.e. due to Costs, Time etc.

3) Where Teeth are so misaligned or over erupted that transitional dentures are impossible to provide. Teeth may be tipped or rotated preventing a suitable denture from being designed

4) When the status and prognosis for the remaining teeth are hopeless.

-What are the advantages of Immediate Dentures (5)

*Maintain Appearance and allows for mastication

Ability to Duplicate Existing Tooth Shade, Shape & Aesthetics of Existing Teeth

Ability to maintain comfortable ICP and favourable Occlusal Face Height

Prevent Lateral Tongue Spread in the Lower Arch Posteriorly

Initial Protection of Tooth Sockets from Food Packing & Stagnation

-What is the effect of Edentulous Patients on their confidence

*1) Perceived Negative Personality Traits

2) Social Avoidance

3) Loss of Self Confidence

4) Premature Ageing

5) Depression

-How is the Anterior Tooth Position Duplicated

*Anterior Tooth position can be recorded by means of a Silicone Putty Index.

This enables the technician to reproduce the appearance of these teeth.

This can also aid lip support, natural appearance and speech.

-What are the consequences if an Immediate Denture is not used

*If an Immediate Denture is not used, resorption will occur for 6-9 months prior to Denture Fabrication.

The Exact placement of anterior teeth would be impossible and vital information regarding tooth position and appearance will be lost forever.

-Immediate Dentures can maintain a patients ICP and OFH. In cases where Immediate Dentures are not provided, what occlusal scheme are dentures made in

*Centric Relation

Also can be the case if the patient does not have a Stable ICP, then use CR

-What are the benefits of Providing an Immediate Denture immediately post extraction?

*1) Aid Haemostasis

2) Reduce Blood Clot Disturbance

3) Reduce Food Impaction into the Socket

-What are the Disadvantages of Immediate Dentures (5)

*1) Pain & Discomfort

2) Difficulty in Predicting amount of Bone Loss post extraction

3) Initial Lack of Patient Proprioception due to Anaesthesia. Can't feel so unable to tell if fit good or bad

4) Increased Long Term Costs as Relines and Remakes necessary within a short timeframe

5) Inability to check aesthetics at Try in Stage if mobile, drifted or overerupted teeth.

-Why do Immediate Dentures cause Pain & Discomfort

*The fitting surface of immediate dentures can cause significant trauma to bony ridges

The operating filed is often full of blood so it is difficult to do PSI tests to find sore spots on the denture. Blood Operative Field impacts the accurate use of PSI paste.

The patient is also numb due to extractions therefore chances of the patient identifying areas like to cause trauma is less too.

This is surgical stent

-Explain why Immediate Dentures increase long term costs

*Bone resorption = continuous after Immediate Denture Placement.

Although immediate dentures initially fit well, bone resorption is rapid post extraction reducing retention and aesthetics of the immediate denture.

This necessitates a remake in many cases. Increasing costs.

-List 6 Considerations when Treatment Planning for Immediate Dentures

*1) Consent & Alternatives

2) Medical Considerations - MRONJ, infective endocarditis

3) Status of Remaining Dentition and Complication Anatomical Factors, Undercuts and tori

4) Jaw Relationships, OFH and existing occlusion

5) Radiographic Investigations

6) Surgical Procedures.

-Stock Trays are not designed to provide impressions for partially dentate patients.

How can Stock Trays be used on Partially Dentate Patients?

*The use of stock trays in partially dentate patients can cause significant gaps to occur in edentulous areas. These areas can be recorded in Silicone Putty or Impression Compound to create a Modified Tray.

Alginate Adhesive must be applied to both the exposed tray in the dentate areas and impression compound before an alginate wash is taken. This provides the tray with stability.

-What is the optimum thickness accuracy for Alginate

*3mm

-What is the Tissue Stop thickness for Silicone?

*1.5mm

-When should Immediate Dentures be reviewed ?

*1) Day 1, adjust fitting surface and occlusion to reduce discomfort

2) After 1 week, correct pain, discuss use of denture adhesives

3) After 1 month, further corrections and consider autopolymerising additions, assess denture hygiene

4) After 6 months, consider a permanent reline if retention is poor

5) After 1 year, replace with permanent dentures

-What Soft Tissue problems can occur due to denture wearing (3)

*1) Infection

- Candidiasis

2) Hyperplasia

- Denture Granuloma

3) Neoplasia

- Dysplasia

- Cancers

-What Oral & Denture Hygiene Advice should be given according to the Oral Health Foundation Guidelines (4)

*1) Daily Cleaning of Dentures using a Toothbrush or Denture Brush and an effective non-abrasive denture cleanser. Soap or Denture Cream not Toothpaste.

2) Daily Soaking in a Denture Cleansing Solution to breakdown remaining plaque. Denture Cleansing Solution should only be used outside the mouth

3) Denture Wearers should not wear their dentures overnight, especially if at increased risk for Denture Candidiasis

4) All Denture Wearers should be recalled at regular intervals and enrolled into a maintenance programme

-If a new set is made for a patient with poor OH, Antifungals can be prescribed. Give Examples

*- Miconazole Gel

- Nystatin Pastilles

-In which Patients should Miconazole Gel be avoided

*Avoided in patients taking Warfarin

-What is Denture Induced Granulomata?

*A Mixture of Hyperplasia and Inflammation often caused by repeated low grade denture trauma such as an Overextension of the denture

-How is Denture Induced Granulomata managed?

*Early Management by adjusting the denture. Surgical Removal is required in large areas of granuloma, prior to embarking on a new denture.

-What is the Classical Presentation of Denture Induced Granulomata

*Central and Ulceration with Granuloma Around the edges. Corresponds to where the Denture Flange inserts directly into this area.

-Describe how Denture wearing can cause suspicion of Neoplasm

*Ulcers, Red & White Patches in the mouth with no obvious cause are suspicious of neoplasms. Refer Urgently.

If there is an obvious cause, manage and review in one week. If it is not healed in one week, then refer.

-What is Protrusive Overclosure

*In very old dentures, Protrusive Overclosure is where the patient slides their mandible forward resulting in loss of significant Vertical Face Height.

This is caused by a combination of Alveolar Resorption and Excessive Denture Wearing

-What are the extra oral signs of Protrusive Overclosure (3)

*1) Loss of OFH

2) Downturned Corners of the Mouth

3) Mandible Postured Forward

-How is Protrusive Overclosure treated (3)

*1) Reline Dentures

2) Occlusal Pivots

3) Replacement or Denture Duplication with Moderate Changes in Jaw Relations

-What are the solutions for Denture Fracture

*1) Metal Mesh Strengthener

2) Cast Metal Bases

3) Use High Impact Acrylic

-List 5 Liners used in Complete Dentures

*1) Heat Cured Laboratory PMMA resins

- Permanent

2) Chairside Autopolymerising

- Permanent

3) Silicone Based Laboratory Placed

- Semi Permanent Soft Liner

4) Short Term Acrylic Resin Based Chairside Soft Liners

5) Tissue Conditioner

- Chairside

-The flanges of old dentures are nearly always overextended due to the ongoing bone resorption process. Why is it vital to remove overextensions

*It is vital to check the denture, identify overextensions and remove them using an acrylic bur before taking the reline impression.

Failure to remove overextensions will mean the existing denture will become even more overextended than at the start.

-What material is used to reline Lower Dentures

*Light Bodied Silicone. Only a thin layer is required and if the correct pressure is applied the silicone layer should only be 1-2mm thick.

-How do you Reline an Upper Denture with Light Bodied Silicone

*When relining an upper denture, it is good practice to cut some perforation in the palatal surface of the upper denture with a fine acrylic bur. This allows an even flow of the material. This reduces the risk of inadvertently increasing the OFH.

-What are the Indications for using Autopolymerising Chairside Permanent PMMA Liners (4)

*1) Provision of a Partial Reline to an Existing Denture

- resorption post root extraction

2) The addition of a flange or correcting an underextension in an existing denture

3) Creation of a Functional Post Dam in an unretentive existing denture

4) Chairside Pick Up Locator Housings in Implant Cases.

-Which Patients benefit from Soft Liners (5)

*Soft Liners Reduce the Traumatic Effects of a Denture for Patients with

1) Thin Atrophic Mucosa

2) Ridge Atrophy or Resorption

3) Deep Anatomical Undercuts

4) Bruxism Tendencies

5) Congenital and Acquired Oral Defects requiring Obturation

-What are the 2 different types of Soft Denture Liners

*1) Silicone Soft Denture Liners (SSDL)

- Technician Fabricates this in the lab

2) Acrylic Soft Denture Liners (ASDL)

- Chairside Fabrication

-What are the drawbacks of Soft Denture Liners (7)

*1) Low Resistance to Colonisation by C.Albicans due to porosity

2) Can Discolour Significantly especially to Nicotine

3) Debonding from the Acrylic Denture Base (SSDL Type)

4) Swell Due to Water Absorption

5) Hardening and Roughness due to leaching out of plasticisers (ASDL)

6) Bitter Taste due to leaching of plasticisers (ASDL)

7) Difficult to Adjust

- Special Burs required

-What is the effect of ASDL (acrylic soft denture liner) when they leach plasticisers 2

*Leaching of Plasticisers can cause the soft liner to become hard with a rough surface.

Soft Liners may debond from the main acrylic body of the denture

-What is the most used Silicone Soft Denture Lining Material

*Molloplast B

-In which forms are SSDL available

*1) Heat Cured

2) Auto-Polymerised Versions

-What is the Optimum Thickness of a SSDL

*3mm

-What are the uses of Tissue Conditioners

*1) Short Term use only to cushion an existing denture in order to relieve inflammation

2) Reduce trauma of the underlying soft tissues prior to the provision of a new prosthesis

3) Can be used to create Functional Impressions

-What are Tissue Conditioners made of

*Poly Ethyl Methacrylate (PEMA)

-Denture Security is often the patient's main concern.

What 2 factors affect the Denture Security

*1) Retention

2) Stability

-What is a key component to Denture Stability

*Size & Shape of the Residual Alveolar Ridge

-In which patients are Bulbous Ridges commonly seen in

*Newly Edentate Patients

-Why is it Important to put Concavities in the Lingual Aspects of Dentures

*Concavities allow the denture to be held in place by the tongue. You should avoid lingual tilting of molar and premolar teeth.

-Which patients benefit from using Denture Adhesive (3)

*1) Patients who are new to wearing Dentures

2) Patients with technically satisfactory dentures experiencing looseness as a result of anatomical abnormalities such as Resorbed Ridges or Reduced Saliva Flow

3) Patients with satisfactory dentures experiencing looseness due to poor neuromuscular control.

-Name common Cream Adhesives

*Fixodent & Poligrip

-What is an Overdenture?

*A denture which gains its support partly or wholly from the roots of retained, decoronated teeth or implants

-What are the advantages of retaining roots and teeth for overdentures?

*1) The retained root preserves the associated alveolar bone

2) The root face gives extra support thus reducing bone resorption elsewhere

3) Additional retention can be gained via attachments

4) Psychological benefits to patient

5) Patient retains proprioception and tactile discrimination

-What are the benefits of retained roots to overdentures?

*1) Roots allow greater occlusal load to be tolerated

2) Roots protect the soft tissues against mechanical trauma

3) Roots reduce general bone loss as the denture is better supported and may rock and tip less.

-What are the Disadvantages of Overdentures ?

*1) Attachments are expensive and the time taken to plan and fit them increases treatment time and costs

2) Roots are prone to caries and periodontal disease. Ongoing Root Maintenance is Expensive.

-Retained Roots require ongoing Maintenance. Describe the maintenance required. 3

*Recall Periods need to be more frequent than if fully edentulous

5000ppm Fluoride Toothpaste indicated

Hygienist treatment around retained roots is required.

-Overdentures are Indicated when Alveolar Resorption is Detrimental. Explain this.

*Imagine Atrophic Distal Ridges to the preserved roots. The loss of these roots would cause resorption of the associated alveolar bone and lead to severely resorbed lower ridge.

This would cause a loss of lower denture stability.

-How much interocclusal space is required for magnets for additional retention

*2.5mm at least

-Once Decoronated, a sound coronal seal must be placed in the coronal aspect of the pulp chamber. Explain Why

*Coronal Seal using RM-GIC or Composite to prevent bacterial ingress into the pulp chamber.

-Which patients should be given Permanent Overdentures

*Only Patients with Good OH, Diet Control and Low Caries Risk.

-How are Abutment Teeth looked after

*Toothbrush and 1450ppm fluoride toothpaste after every meal

Provide denture hygiene advice.

5000ppm Fluoride Toothpaste according to DBOH as Overdentures are a High Caries Risk

Remove at Night to reduce caries risk and periodontal disease.