INSERTION, CHECKS & MAINTENANCE

what are the general categories of denture faults

• patient related

• laboratory related

• clinician related

what are some patient related denture faults

• systemic diseases: Parkinson’s, dyskinesia, hormonal

• local pathology: atrophic (flat) ridges, fibrous ridges, large bulbous ridges, undercuts, anomalies such as lumps and bumps, tori

outline torus palatini and its affect on wearing dentures

torus palatini: benign bony protrusions on the roof of the mouth

• difficult to place posterior border of denture

• creates a rocking force on dentures

• can reduce the amount of palatal coverage for dentures causing reduced retention

what are some laboratory related faults

• technical errors 

  • investment - tooth movement

  • processing - flash, post dam

• damage to the model

outline investment

investment: covering a wax model of the denture in a special plaster material in the laboratory

what issues can there be with the investment stage

investment: covering a wax model of the denture in a special plaster material in the laboratory

• there can be a small amount of tooth movement when the denture is invested

• air bubbles in the plaster can cause surface defects on the denture 

• weak plaster can cause movement of the teeth

what issue can there be with the processing stage

• ‘flash’ excess acrylic can cause general defects

what are some clinical related faults

• impression defects

• registration errors

what is an example of an impression error

debonding of alginate at primary impressions

what anatomy can lead to inaccurate registrations and why

• an atrophic ridge

• difficult to get bite registration block to stay still on an atrophic ridge - can be slight movement when patient closes blocks together

what are the steps for denture placement technique

1. inspect fitting surface

2. insert - correct faults

3. check occlusion - correct faults

4. fitting surface - remove pressure spots

5. security - correct faults

how can the fitting surface be checked for rough areas

checking the fitting surface for rough areas

• cotton wool test

  • run along FS, if dislodged or sticks then smooth that area before insertion

• can also use a gloved hand to run along FS

—

also ask patient once they have the denture in if there is anywhere they feel uncomfortable

what tool is used to check articulation

• articulating paper - can give false results

what two recorded positions need to be coincident in patients with full dentures

ICP and RCP

what is the purpose of the precentric check record

• to check occlusion

outline the precentric check record process 

• put a small amount of wax/ silicone over the molar teeth on the right and left

• get patient back into centric relation

• manipulate the mouth slowly closed just before the RCP so the teeth indent the wax/ silicone but they are not coming into contact themselves

what occurs after the precentric check

• teeth are sent back to the lab and remounted in plaster and put on articulator (helps stabilise the dentures so they do not rock when tapped together)

• occlusion is checked on the articulator

• gradually adjust and deepen the fossae to improve and increase the number of occlusal contacts - do not reduce cusp height 

image of pre and post centric check record

what other aspect of occlusion needs to be checked for

tooth contacts during lateral movements

how are lateral movements checked for 

• adjust using BULL

• Buccal Upper cusps and Lingual Lower cusps

• used in class I cases

how can pressure spots on the fitting surface be removed

• by using Coltene PSI paste

• PSI = pressure spot indicator

how should PSI paste be used

• 4cm of PSI paste for 1 quadrant

• keep each paste at the width of the nozzle it comes in

how should the PSI paste be applied

• mix quickly and apply evenly - should be pale green not mint green

• insert into patients mouth, press firmly and border mould well

how can you tell where the pressure spots are after using the PSI paste

• where the denture shows through the PSI paste are where the pressure spots are

what is the pencil in the PSI kit for

• marking where the denture shows through the PSI paste

how should the denture be adjusted after marking with the PSI pencil

• peel PSI paste away

• use bur to adjust denture where the pencil marks have been made

which burs should be used for denture trimming

• LHS: hard to reach areas

• RHS: good general purpose bur

what feature of a denture can cause denture insecurity

overextensions

how are overextensions corrected

• place index finger on denture gently and pull up on cheeks and lip

• if the denture pulls up, it is overextended

• trim until the denture is not displaced

what is another reason for denture insecurity

• inadequate post dam region

how is an inadequate post dam corrected

• use autopolymerising acrylic resin to create a more functional post dam

if there is insufficient space for the midline frenum what problem can arise

• the midline frenum will push the denture downwards when the patient talks or smiles if there is insufficient space for it to move

how should patients be advised on pain when wearing dentures

• incredibly common in first week

• reassure that you are always contactable and this is normal

• if dentures must be removed due to pain, wear for 25h prior to next appt.

• book patient in the week after for their review appt.

__________ plays a large part in denture success

psychology plays a large part in denture success

what is the best way to keep dentures clean

• a combination of mechanical and chemical cleaning

  • mechanical: using a soft bristled brush

  • chemical: soaking

what should you ask the patient to do before their review appt.

• bring the products/ equipment they used to clean their dentures to ensure they are following manufacturers instructions

what is denture stomatitis caused by

• result of poor denture hygiene

• also caused by patient sleeping in their dentures at night - discourage this

what should dentures not be soaked in

household bleach/ oven cleaner/ any domestic cleaners

what can be a barrier to good denture hygiene

• patients with arthritis/ difficulty gripping a brush

how can difficulty gripping handles be solved

• silicone putty can be added to handle to give the patient a better grip

what are denture fixatives

• adhesive that secures dentures to the gum

• should be encouraged

what is a major cause of ulcers in denture wearers and how can this be managed

• dry mouth

• recommend dry mouth mouthrinse e.g. biotene

what else should you give patients at the end of their appt.

• written instructions 

• in case they forget verbal instructions