Occlusal Registrations Flashcards
What is occlusal registration?
records the relationship between the maxilla and mandible when the opposing teeth are in contact
Where should your post dam be placed?
should be placed on non movable soft tissue behind the hard palate
What are occlusal rims usually made of ?
wax
wax and acrylic
What is the benefit of using an acrylic base plate?
the possible addition of a post-dam to improve retention
What are the factors to consider and record in an bite registration ?
- vertical dimension
- horizontal relationship
- soft tissue support
- Teeth- position, shade, mould, setting
What is the vertical dimension?
how far away the chin is from the nose
What is the risk of overclosure?
there is the risk of developing angular chelitis
What is the risk of overclosure?
there is the risk of developing angular chelitis
What should you consider in the case where a patients old denture is overclosed?
how much greater of a vertical dimension the patient can tolerate
What denture components contribute to soft tissue support in complete dentures?
- vertical dimension
- position of incisors
- labial contour
- arch width
- buccal contour
What part of the maxillary complete denture provides primary support?
the hard palate
What part of the maxillary complete denture provides secondary support?
the ridge crest
What part of a -/C provides primary support to the denture?
the buccal shelf
the primary load is located on the buccal shelf
What part of the -/C provides secondary support to the denture?
lower ridge crest
pear shaped pads- the retromolar pads
What is the sequence you should follow for checking you upper occlusal rims?
- disinfect the wax rims and plaster models
Check
* fit and extension
* labial contour
* buccal contour
* occlusal plane
In order to record the occlusal plane, how should wax be removed?
*you should remove wax to the level of the incisal edges
this is the level where your incisal edges will sit
What is the neutral zone?
this is a space where the function of the musculature does not unseat the denture
it is also where the forces generated by the tongue are neutralised by the forces generated by the lips and cheeks
it is essentially the area the muscle impacts the least
Where is the neutral zone usually located?
directly over the ridges
What is a potential consequence of straying outside of the neutral zone?
this can lead to patient cheek biting
What can you use to potentially find the neutral zones?
viscogel
How should the fox’s plane guide be lined up?
lined up with eyes - interpupillary line
Line up with alar tragal line
What should you check on you lower block?
- fit and extension
- labial contour- lower incisors over the ridge
- adjust occlusal surface to give vertical dimension and even contact with upper block
- check appearance
- review upper block if necessary
What happens if your lower block is over extended?
begins to raise
What is the ideal freeway space allocation for C/C?
3mm
What are the consequences of a vertical dimension that is too great?
- feels like a mouthful
- muscular effort to close lips
- teeth touching at rest
- teeth clacking when eating and speaking
- pain under dentures
- ulcerations
- ridge resorption
What is the consequence of a vertical dimension that is too small?
- patient looks old
- lip rolling outwards or inwards on closure
- deep lines at corners of mouth
- often very comfortable
*
What vertical dimensions should you record?
OVD- occlusal vertical dimension
RVD- resting vertical dimension
How should you measure OVD?
measure with existing dentures in place and teeth in contact
How should you measure RVD?
ask patient to relax
lick lips and breathe out
this allows teeth to come apart
How do you calculate freeway space?
RVD-OVD= FWS
What must there be after adjusting upper and lower blocks?
there should be even contacts between upper and lower rims
What guidance can you use to record you canine line?
flare of the nose
Why is medium bodied silicone inappropriate for securing rims together?
takes 2 minutes to set as opposed to reg mousse which takes 20 seconds to set
What is the best position to record your bites before sealing your occlusal rims?
in the retruded contact position (RCP)
How can you record bite on partial occlusal rims?
- place soft wax (cardium wax) onto the block surfaces and get patient to bite through the wax
- cardium wax displaces around both sies and does not go into undercuts
What marks should be on your occlusal blocks?
centre line
smile line
canine lines
When occlusal rims are correct, they are sealed in the patients mouth in their natural position or the …
retruded contact position
What aids can you use to decide the mould of teeth you would like to use?
- Look at old dentures, if okay, take impression
- measure incisal width, incisal length, total width 3-3
- if these are all not okay, use smile lines, canine line and judgement
What is the purpose of the alma gauge?
- allows the position of the incisal edges of an existing full upper denture to be reproduced on a registration block
- it is important if the appearance of the existing denture needs to be reproduced exactly
relative position of the incisal edge to the incisive papilla is compared
What does dimension A using the alma gauge give?
vertical dimension
What does dimension B of the alma gauge give?
the horizontal seperation from the incisive papilla and the incisal edge
essentially the overjet
