W6 Flashcards
List clinical work phases of complete denture fabrication
- C. From complaints to the prognosis. Primary impression-taking.
- C. Outlining the border of the special tray
- C. Adjusting the special tray. Secondary impresison-taking
- C. Recording jaw relation, facebow transfer, tooth shade and shape selection
- C. Try-in of the trial denture
- C. Fitting
- C. Short term recall
- C. Long term recall
List laboratory work phases of complete denture fabrication
- L. fabrication of primary cast
- L. Fabrication of the special tray
- L. Fabrication of the secondary cast and OCCLUSAL RIMS
- L. Mounting the casts into the articulator, fabrication of the trial denture
- L. processing the final denture
List PARTS OF THE OCCLUSAL RIMS
Name of these equipments
Which piece of information does occlusal rim provide?
Provides an appropriate vertical and horizontal relationship of the mandible to the maxilla
-> Information for the dental technician about Central Occlusion with the help of wax record rims
When should the occlusal rim be used?
when restoring edentulous patients with removable, implant-fixed or fixed prostheses
The wax record rims should be placed on ___
well-fitting rigid bases
What are Suitable materials for the bases of occlusal rim?
Shellac
Wax
Light-curing acrylic resin
Heat-curing acrylic resin
Characteristics of Shellac when being used for occlusal rim
deform or fracture in use, good adaptation
Characteristics of WAX when being used for occlusal rim
non enough rigid base, is likely to change shape during the recording procedure
Characteristics of Light-curing acrylic resin when being used for occlusal rim
the quickest and easiest of materials
Characteristics of Heat-curing acrylic resin when being used for occlusal rim
the best fitting, allowing max. retention
Disadvantage of Occlusal recording rims
prognosis of retention is poor
The name of the system used for Occlusal recording rims
Acrylic basic plate system
6 Basic mandibular positions
- Rest position
- CR
- CO
- OVD-Occlusal vertical dimension
- RVD-Rest vertical dimension
- Freeway space
Describe Rest position (a basic mandibular position)
The vertical and horizontal position , when the mandibular musculature is relaxed and the patient is upright
There is a space between the occlusal surfaces of the teeth= Freeway space=Interocclusal rest place (2-4 mm)
Describe CR - Centric relation (a basic mandibular position)
The mandibular jaw position in which the head of the condyle is situated as far anteiorly and superiorly as it possible can within the mandibular fossa
When should we use CR - Centric relation?
when restoring edentulous patients with removable, implant-fixed or fixed prostheses
Why is CR - Centric relation important?
Important the reproducibly relate the patient’s maxilla and mandibl
What is Intercuspal position?
( CO-Centric occlusion)
It is the vertical and horizontal position of the mandible in which maximum occlusal contact occurs
Describe Rest vertical dimension (RVD) (a basic mandibular position)
When mandible is in its resting position, this distance is RVD.
The distance between two selected points:
1. Related to the maxilla (Nasion)
2. Related to the mandible (Gnathion)
Describe Occlusal vertical dimension (OVD) (a basic mandibular position)
When the upper and lower teeth are in contact is known as the OVD.
The diffference between RVD-OVD=Freeway space
What is Freeway space?
The diffference between RVD-OVD
Characteristics of Freeway space
1/ In rest position of the mandible
2/ An excessive freeway space is provided, the load of the tissues is of course reduced
3/ 2- 4 mm
How to do CO (Centric occlusion) registration?
- Measuring of vertical dimension
- Measuring of horizontal dimension
(With the help of occlusal rims)
How to measure the rest RVD ( Rest vertical dimension)
- Patient need to be calm
- Without external stimuli, no disturbing noises or bright light shining in the patient’s eyes
- Swallowing, make sounding M before trying to relax the mandible
Measurement of the vertical
dimension
- Try in of the occlusal rims and plates
- RVD is measured as the distance between 2 selected points (Maxilla, mandible)
- The two-dot technique Willis gauge - Measurement of OVD
What type of cast is used for measurement of the vertical dimension?
Funtcional cast
Name of these 2 points when doing Measurement of the vertical dimension
Signing of Gnathion-Nasion points
Adjusting of upper occlusal rim
-> What should we do before adjusting?
any adjustement upper and lower record blocks should be placed in the mouth in turn and checked for
What are the 2 basic objectives of adjustment of upper occlusal rim?
- Two basic objectives
To establish the correct orientation and level of the occlusal plane - To produce the correct shape for the labial, buccal and palatal surfaces
How is the rim adjusted during adjustment in the coronal plane?
The rim is adjusted so that the occlusal plane is parallel to the interpupillary line
How is the rim adjusted during adjustment in the sagittal plane?
A useful guideline for saggital orientation of the occlusal plane – is the ala-tragal line
How do we establish the level of the occlusal plane?
- Establishing the level of the occlusal plane
- The incisal level of the upper rim is related to the upper lip
- Short lip- long upper lip
- Modifying the incisal edge of wax rim
- Controlling! During function by smiling, saying few words while wearing the record block
How do we shape the labial and buccal surface?
- Lip supports depends upon the position and inclination of the labial face of the wax rim
- Palatal surface: Essential to create adequate space for the tongue
How do we adjust the lower record rim?
- Adjusting the height of the rim to the required occlusal vertical dimension
- After the establishing oft the upper occlusal rim , the lower rim will be governed by it
- Fitting them into the required occlusal vertical dimension OVD
Disadvantages of non fitting lower occlusal rim
- Unstable lower rim
- Displacing of the cheek and lip mucosa
- Not enough place for tongue
Why is Horizontal dimension important?
Recording the retruded jaw relationship
Active, Myodynamic, Passive
Why is Definitive recording important?
- Deciding whether the facial proportioners look correct, if the lower third of the face appears too long or too short
- Assessing speech with the blocks
- Reference to previous dentures
Definitive recording
-> Before finally fixation of occlusal rims, what should we do?
- Are the rims stable?
- Is there adequate freeway space?
- Occlusal contact?
- Is there a pleasuring appearance?
- Has a consistent retruded jaw relationship
been established? - Spatula try-in
