3 - Techniques for Determining VDO, Lab 3 (Edentulosu Record Bases and Wax Rims) Flashcards
how do you determine occlusion on edentulous patients
joint position and anatomical landmarks
what are the average heights of wax rims
22 mm max
18 mm mand
wax rims are adjusted for what
- esthetics
- phonetics
- function (freeway space)
intraoraaly to determine patient VDO
difference between natural and complete denture occlusion
- Natural teeth are suspended in the bone by PDL which acts as a shock absorber
- Denture teeth are part of the denture base which rests on movable/displaceable tissues
- Premature, deflective contacts between artificial teeth cause movement of the denture resulting in damage to the supporting tissues
goals of complete denture occlusion
- limit trauma to supporting tissues
- preserve remaining structures
- create stability of dentures
- restore esthetics, speech and mastication (function)
what is the simultaneous contacting of maxillary and mandibular teeth on the right and left in the anterior and posterior occlusal areas when the jaws are in centric or eccentric relations
balanced occlusion
is facebow (ear bow) record a joint or bite registration
joint
what is a hypothetical line thru two mandibular condyles around which mandible may rotate
hinge axis
what is difficult to determine in edentulous patients and requires special armamentarium (fully adjustable articulator)
true hinge axis
what is an estimated axis loaction, using any current technique will place the position +/- 6 mm of the true hinge axis
arbitrary hinge axis
ear bows use the external auditory meatus reference point as what
arbitrary hinge axis
what refers to the length of the face
vertical dimension
what is the distance between two points: fixed point at tip or base of the nose and on the movable mandible (usually chin)
vertical dimension
what is the length of the face when the teet are in contact and the mandible is in CR
VDO
what is the length of the face when teeth are separated and mandible is in physiologic rest position
VDR
T/F: VDR equals VDO
FALSE!
what is campers plane
bottom of ala of nose to top of tragus (ear)
what is inter pupillary line
line drawn parallel from right pupil to left pupil
average nasolabial angle for men and women
men 90-95 degree
women 95-105 degree
when contour mx wax rim, lips at rest, the wax should project how many mm below lip line
1-2 mm
do males or females have more tooth exposed with relaxed lip
Females
the older the person, are the maxillary anterior teeth more or less visible
less visible
what sounds can be used to verify length of maxillary wax rim contour
fricative sounds (fourty, four etc)
mandibular occlusal plane cannot be above what
1/2 way up retromolar pad
what is the opening of parotid gland near second premolar
parotid papilla
what is the chiasma of facial muscles held together by fibrous tissue lateral and superior to each angle of the mouth
modiolus
what is the meeting place of buccinators and other facial muscles near mouth angle
modiolus
with teeth loss, the modiolus is displaced with given appearance of what
sunken cheeks
T/F: the buccal surface of the lwoer denture at premolar region must be thin to avoid the modiolus lifting the denture
TRUE
how to mark high lip line on mx wax rim
have patient say “Eeeeeew”
the average VDR is ___ mm greater than VDO
2-4 mm
in natural dentition, the teeth are separated and the degree of separation is called ___
free way space (2-4 mm seperation)
what phonetics help determine VDO
siblants (church, six, seven)
space 1-2 mm in PM area
what phonetics determine lip support and incisal edge position
fricatives - F and V sounds
what phonetics can be used to determine facial muscle relaxation
“m” or “emma” or hum
how many measurements do you take to measure VDR
3
what phonetic tests is ued to determine if VDO allows lip competency
plosive - peter picked a pickled pepper
occlusion of opposing teeth when the mandible is in centric relation which may or may not coincide with maximum intercuspation
centric occlusion (CO)
a maxillomandibular relationship in which the condyles articulate with the thinnest avascular portion of their respective discs in their most anterior superior position against the slope of the articular eminences
centric relation (CR)
___ with teeth present is a tooth to tooth relation
whereas
___ is a static position with a bone to bone relation
CO, CR
what can be used to generate CR records
waxes (alu wax), impression compounds, ZOE paste
CR is a reference point in recording what relations
maxillo mandibular relations
is CR dependnt or independent of tooth contact
independent
what record can be verified and repeated and is a functional position
CR record
what record is the start point for developing occlusion
CR record
you first establish VDR and VDO by adjusting which rim
lower wax rim
how many apointments needed to make a denture
8 appointments
how many appointments involve lab work
5
how many appointments involve delivery of denture
3
what can be placed on palate to prevent slight shrinkage of triad
tin foil
how wide should the wax rim be anterior, premolar, and molar area
anterior: 5 mm
premolar: 7 mm
molar: 10 mm
