Denture try-in, insertion, and review Flashcards
Before the patient arrives for a denture try-in, what are the critical laboratory work checks that must be performed?
- Verify presence of lab work
- Confirm correct patient identification
- Check for transit damage
- Verify work matches prescription specifications
- Confirm mould and shade match request
- Verify special instructions (e.g., diastema/imbrications) have been followed
What specific checks should be performed on the try-in bases before patient insertion?
- Verify stability on casts
- Check for smooth, rounded borders without sharp edges
- Confirm border extension matches depth and width of functional sulcus
- Examine wax for distortion and adaptation
- Verify even occlusal contacts without anterior open bite
- Check centerline coincidence
- Verify articulator pin position on table
When examining the lower try-in from an occlusal view, what are the key aspects to evaluate?
- Position of posterior teeth relative to ridge
- Position of anterior teeth relative to ridge
- Assessment of tooth position’s impact on denture stability
- Verification of correct tooth count
- Confirmation of shade and mould accuracy
When examining the upper try-in from an occlusal view, what are the key aspects to evaluate?
- Are the posterior teeth set buccal to the ridge?
- Are the anterior teeth set how you expected?
- Is the position of the teeth likely to affect the denture stability?
- Correct number of teeth on try-in?
- Correct shade & mould?
- Post dam (if not cute draw on cast in pencil and prescribe)
What is the try-in checklist?
Retention & stability
Base extensions
LIMBO
Lip support
Incisal level
Midline
Buccal corridor
Occlusal planes – anterior/posterior
Position of teeth compared with the soft tissues
Vertical dimension FWS
Even contact in occlusion (in RCP?)
Speech
Aesthetics
How should you test speech?
Listen:
Test fricatives with try-in in place:
Count from 60-70; days of week; Misssissippi; Forfar 5 East Fife 4
Listen to f and v sounds to assess the contact between the incisors and lower lip
Not too much whistling on “s” sounds
Look:
Teeth should be slightly apart during speech
What speech-related problems during try-in indicate the need for a re-try appointment?
- Teeth making contact during speech (insufficient FWS) - requires OVD reduction
- Significant whistling during “s” sounds - may need OVD increase
- Anterior tooth position correction if set in incorrect class
- Process requires:
- Re-register at new OVD
- Lab remount
- Reset for re-try
Note: Minor speech issues may be due to poor wax/shellac adaptation and can proceed to insertion
What to do if something is wrong aesthetically?
- Shade/mould incorrect – Choose again, > lab for reset with new teeth for re try-in
- Midline incorrect – Mark new midline, > lab for reset all teeth with existing teeth for re try-in
- Minor changes to tooth position eg
imbrication/twists – you alter at chairside until
patient approves > lab for insertion - Major changes to tooth position eg major LIMBO
What is the golden rule?
Patient consent to finish
Record consent in the records
How to fix extension problems?
minor/major under/over
- Minor overextension – Modify wax; mark on master cast maximum extent of flange > lab with specific instructions for insertion
- Major overextension – Usually need to go back to master imp stage
- Minor underextension – 2 options: 1) wash impression in try in (closed mouth technique) > lab for casting/mounting > re try-in 2) Proceed to insertion stage but do not insert at that stage but instead reline denture
- Major underextension – Usually need to go back to master imp stage
What to do if OVD is wrong?
always triggers a re try-in
- If OVD is increased teeth need to be removed from one or both dentures and replaced with a wax rim.
- If OVD is decreased a wax rim can be added to the teeth on one or both dentures or teeth removed from one or both dentures and replaced with a bigger wax rim.
An example: If the upper is correct but lower denture is too high so increased OVD
1. remove the lower teeth
2. replace with wax
3. Re-Record the registration at correct OVD
4. Proceed to re try-in.
What should you do if there is an occlusal error and the OVD is correct?
If uneven contact some or all teeth need to be removed from one or both dentures and replaced with a wax rim, re-register > remount > reset > re try-in
What should you do if there is an occlusal error and the OVD is incorrect?
Correct OVD by removing teeth from one or both dentures and replace with a wax rim, re-register occlusion to eliminate occlusal error > remount > reset > re try-in
What to do if there a minor occlusal discrepancie?
Slight slides or very minor errors
Selective grinding at either try-in or insertion
Use articulating paper
Remember try-in bases are unstable and denture moves
Adjust carefully
BULL rule.
Buccal Upper (Palatal surface of buccal cusp) & Lingual Lower (buccal surface of lingual cusp). Adjust the contacting surfaces rather than the tips of the cusps
What comprehensive checks should be performed on the denture before patient insertion?
- Examine all three surfaces (fit, polished, occlusal) for:
Blebs
Sharp edges
Acrylic flash
Polish quality - Check for porosity or inclusions in acrylic
- Identify large undercut areas that might:
Prevent seating
Cause pain - Verify appropriate border extension
- Confirm overall quality of laboratory work
