Complete Denture construction stages Flashcards
For denture anatomy i can’t upload photos so look at lecture
lol what a pain
Hamular notch
between distal surface of tuberosity andhamular process of the medial pterygoid plate
DISTAL BORDER OF DENTURE - PERIPHERAL SEAL
Denture retention - anatomy
Hamular notch
ridge
full depth and width of sulcus
Retromolar pad purpose
AIDS SUPPORT
- triangular soft pad on tissue
posterior edge of edentuloud ridge
Retromylohyoid space
AIDS RETENTION AND STABILITY
-distal end of lingual sulcus, posterior to mylohyoid muscle
Cawood and Howell ridge classification
I - dentate II - post XLA III - broad alv ridge IV - knife edge ridge V - flat ridge VI - submerged ridge
Edentulous patient - bone change
No remaining teeth or roots
No remaining periodontium
No means of retaining the alveolar bone around teeth
Maximum rate of bone loss in the first 3 months
Bone loss continues over the lifetime of the patient
Tissues not created to withstand load from dentures
Extraoral changes in edentulou patient
Loss of facial height
Altered profile
altered low and up lip
Physiological changes in edentulous patient
Loss of proprioception Decreased masticatory efficiency Decreased incising efficiency Decreased swallowing efficiency Problems with speech
What is support and how is it achieved with anatomy
Resistance to occlusally directed load
Mandible
buccal shelf, residual ridge and retromolar pad
Maxilla
hard palate, residual ridge
What is retention and how is it achieved with anatomy
Resistance to vertical displacement of denture
Accurate fit of the denture base to the mucosa so that the space between the two is as small as possible.
Border seal achieved by extending the denture flanges to the depth of the functional sulcus and incorporation of post dam on C/
Avoid frenal attachments
What is Stability and how can it be tested
Resistance to horizontal displacement of denture
Impression compound features
NON elastic NOT accurate dimensionally stable Primary imps NOT FOR FLABBY RIDGES
Alginate features
NOT dimensionably stable
ELASTIC
accurate
messy
Silicones features
HYDROPHOBIC
Variable consistencies
Accurate
Dimensionably stable
Polyether features
HYDROPHILLIC
Single consistency
Accurate
DImensionably stable
What is balanced occlusion
As a jaw recording for complete denture wearers is made in the retruded jaw position the artificial teeth must be
adjusted to enable a degree of protrusive movement by approximately 2 mm into a centric relation position or (ICP). This applies to posterior teeth in contact but also must account for the anterior tooth relationship which should have approximately 2 mm of overjet to enable this transitional movement
Name 4 different types of base irregularities in acrylic
- Contraction - insufficient pressure during processing (everywhere)
- Granular- incorrect mix ratio (rough surface everywhere)
- Gaseous - boiling of monomer (Thick areas of baseplate)
- Crazing - Coefficients of thermal expansion e.g. porcelain teeth and acrylic base plate/Prolonged stressing during function (fine cracks)
Taking impressions - process
- Select stock tray size, try in,
- Undercuts will determine the imp material
- Place material in tray
- Stand infront -low, Stand behind - UP
- check all areas of imp, repeat if necessary
How to use Impression compound
Place in bowl with paper at bottom. Hot water 55-60 degrees. place in for 4-5 mins. (plasticiser may leak out if longer)
Spacing for material use in secondary imp
-Alginate 3mm
-Silicone/polyether
•spaced 2mm (often upper)
•Close fitting 0.5-1mm (often lower
What are stops used for in secondary imps
create space for material and correction of posterior border (Up -canines/post dam) (Low - Retromolar pad/canain region)
Objective of jaw registration (5)
- define max rim shape
- determine occlusal plane
- determine jaw relationship
- define lower teeth position
- select shade and mould
Steps of registration
Step 1: Adjust the upper record block Step 2: Lip line and occlusal plane Step 3: Measure vertical dimension and establish face height Step 4: Lower tooth position Step 5:Registration Step 6: Selection of teeth LIMBO
What will cause the block to drop
- Too much lip support
- Overextension
How to test incisal plane level
‘F’ Sound
Look
lip level
Ideal tooth position
Anteriors - 1cm in front of incisive papilla
canine - below nose
Over ridge, neutral zone
Lines to mark on registration
Centre line
Canine line
lip line/smile line
occlusal plane
Methods to measure facial height
HOW
- Visual
- Dividers
- Willis bite gauge
- Mark two point of minimal muscle interference
- ask partient to moisten lips
- reduce lower block until upper contacts the upper evenly
RVD - OVD = FWS , 2-4mm
If retention of a jaw reg is poor, what should you do
- check extension
- teke imp
- correct occlusion
- record occlusion
Checks prior to inserting tooth trial
- correct trial for patient
- fit on cast
- finish
- occlusal contact
- centre lines meet
- OJ/OB
- Teeth set = over ridge
- inclination of incisors - space for tongue etc.
Check surfaces - polished,impression, occlusal surfaces
What is Hanua’s quint
5 factors that affect balanced occlusal articulation
- Sagittal condylar guidance angle
- Inclination fo occlusal plane
- Cusp height
- Compensating curve
- Incisal guidance angle
Tooth trial in mouth - Sequence
One at a time, moisten. LIMBO Extension, Stability, Retention, Incisal plane angulation - fox's plane guide Aesthetic and speech
Balanced occlusion definition
-5 determinants = Hanau’s quint
Occlusion with similataneous contact of all/most occlusal surfaces on both sides of the arch in all mandibular positions
- Sagittal condylar guidance angle
- Inclination fo occlusal plane
- Cusp height
- Compensating curve
- Incisal guidance angle
Speech evaluation:
- Teeth contact during speech
- Whistling sound while speaking
- Not enough inter-occlusal space
2. greater FWS, treat by >OVD/change anterior tooth position
Denture delivery steps
Extension •Retention •Stability •Occlusion •OcclusalPlanes •OVD, FWS •Appearance •Speech
What is selective grinding
Use articulating paper
Remember bases are unstable and denture moves
Adjust carefully
BULL rule.
Buccalupper (Palatal surface of buccalcusp) and
Lingual lower (buccalsurface of lingual cusp).
Adjust the contacting surfaces rather than the tips of the cusps
Re-record occlusion if incorrect
clinic 1.Remove the lower teeth (if upper is fine) 2.Replace with wax 3.Re-Record the registration 4.Prescribe another wax trial 5.Give both dentures to the lab laboratory Laboratory remount on articulator Reset lower teeth clinic Retrial
