why a trial stage?
Dress rehearsal
- Dentist
- Function
- Aesthetics
- Patient
- function
- Aesthetics
- Check technical work
imp Qs before pt arraives
- Are they the correct dentures?
- Do they fit the models?
- Are the models damaged?
- Is the work ready – did you put the correct date on the card (check the day before)
- Check instructions on lab card before the patient arrives- day before preferably.
- Distance travelled by patient/ work not ready / problem
Is the mould and shade what you requested.
Arrangement of teeth. Did you request a diastema/imbrications.
3 things to check when first pick up dentures before pt arrives
- The trial bases are stable on the models (rocking)
- The borders of the trial bases are smooth, rounded and no sharp edges
- Extension of the border is shaped to the depth and width of the functional sulcus
before you insert the dentures check
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- Trial on articulator
- Is the wax distorted or well adapted
- Check the occlusion.
- Satisfactory occlusal contacts
- Is there an anterior open bite or good contact
- Are centre lines coincident
- Examine the dentures in lateral profile.
- Look at the overbite and overjet.
- Is it excessive
- Look at the occlusion on the molars.
- Are there even contacts
- Are the teeth set over the ridge – esp lowers
- Is the position of the teeth likely to affect the denture stability
- Do you need to include the last molar or would it be better to give increased space for the tongue. Each case is different.
- Check the position of the anterior teeth.
- Check the shade and mould.
what to say to the pt when they arrive for trial appointment
Tell pt trying them in today and if all well nice short appointment but gives us time to adjust them if needed
how to insert the trial dentures
Assess each denture independently & then together.
- Allow time to settle
- Insert one denture at a time (moisten)
If maxillary denture is inserted first it can be dislodged when the mandibular denture is inserted.
3 key things to check when trial denture in the mouth
- Extension (& adjust if necessary)
- Retention
- Stability
NB. Retention is not as good with trial as it is with finished denture
how to assess extension
- Hold tissues away from denture – does it drop? If yes – possible underextension
- Any overextension of the peripheries and it will drop when you manipulate tissues
- Too much lip support and it will drop
- Use the wax knife to make adjustments (not fitting surface)
resistance
Resistance to VERTICAL movement (away from occlusal surface)
stability
Resistance to HORIZONTAL movement (Rocking)
what to check about occlusal plane and appearance
- can do this for individual upper or lower before together
Incisal plane orientation – with interpupillary (parallel)
occlusal plane orientation -with alar tragal line
how to assess lower occlusal plane and why imp
For most patients the level of the incisal edge is at the level of the lower lip at corner of the mouth
- If the occlusal plane is too high the tongue will be cramped and the denture will be unstable
tongue should rest on the occlusal surfaces of the teeth to help hold the denture in position
what needs done if OVD is increased
teeth need to be removed from one or both dentures and replaced with a wax rim
if OVD on upper is correct but lower is wrong
- remove the lower teeth
- replace with wax
- Re-Record the registration
- Prescribe another wax trial – order another retrial
Try prevent altering the upper unless needed
check occlusion on wax trial
- Balanced Occlusion
- Balanced Articulation – contact on both working and non working sides on sliding (complete want both unlike dentate)
- Centric relation (RCP) = centric occlusion in edentulous cases
ask if comfortable bite or too high
balanced articulation
contact on both working and non working sides on sliding (complete want both unlike dentate)
what to check after checking extension, stablity and retention when trial dentures in mouth (6)
- incisal and occlusal planes and appearnce
- OVD and FWS
- occlusion
- pt opinion
- speech
- post dam
what to ask the pt when they have wax trial in
- Are they comfortable.
- Do they feel loose (Remember the retention at the trial stage is reduced)
- What does the patient think of the appearance.
- Is there anyone with the patient who can comment.
- Is the speech clear.
- The wax trial dentures will move more than the processed dentures but they should be retentive and stable enough for you to check the speech (wax more bulky)
- Remember wax melts so don’t leave them in the mouth too long.
how to assess speech with wax trial
- Ask the patient to “count from 60 to 70” or “say the days of the week”
- If the teeth make contact during speech then there is not sufficient inter-occlusal space between the teeth.
- The occlusal vertical dimension needs to be reduced to give more freeway space.
- If the teeth make contact during speech then there is not sufficient inter-occlusal space between the teeth.
- If there is a whistling sound during sss then air is escaping.
- The vertical dimension may need to be increased or the anterior tooth position changed.
- Check the f and v sounds to assess the contact between the incisors and lower lip.
importance of post dam in upper denture
good peripheral seal
what do you need to do at trial stage for post dam
- Draw on cast where you want it with pencil
- Ask technician to cut the post dam
- Sometimes ask for a double post dam
- 2 – one for max coverage but it pt insists to far back can reduce the denture but still have adequate peripheral seal
- Sometimes ask for a double post dam
prescription card for after trial appointment
Guide
- What do you want done with the work you give
- “please prepare post dam to xxmm”
- What do you want back
- “please process in heat cure acrylic and provide c/c” (complete denture)
- Any special instructions
Instructions to the laboratory
- Are they ready to process in heat cured PMMA
- Do you need a re-trial?
- Have you re-recorded the registration and need models re-articulated? - YES
- Do changes need made & are your instructions clear?
- Where is the post dam and is it marked
stage for prescription card
what is the next stage not what you have done (retry or finish)
acronym to remember what to check at denture retrial stage
SOARE
- Stability
- Occlusion
- Appearance
- Retention
- Extension
