Occlusion Flashcards
how will monoplane occlusion result in group function?
respect to canines?
if the canines are far enough apart
what causes the unilateral posterior group function in monoplane? (ex- right lateral)
inclination of the condyles - cusp flat but curved condyle so it matches the curve of condyle and opens
what is required to not have anteiror contact in protrusion with denture?
increased Horizontal overlap
decreased vertical overlap
in wax you
what controls the excursions by the condyle?
+/- curve of wilson or spee - which controls the excursion of the condyles
rules for balanced occlusion
Bilateral posterior contact in CO
Bilateral posterior contact in Lateral
Bilateral posterior contact in protrusion
NO anterior contact in CO or lateral
optional contact in protrusion IF CONTACT IN ANTERIOR IS SIMULTANEOUS WITH POSTERIOR CONTACT
balanced occlusion REQUIRES?
- absence of anterior contact in CO
- Absence of incisal guidance in protrusion
- Absence of canine guidance in lateral
- PRESENCE OF COMPENSATING CURVES
compensating curves compensate for what?
the articular eminence
with the curves we can have posteiro contact for longer - as opposed to monoplane when we open up sooner
compensating curve
curve of the occlusal plane that compensates for the curve of the articualr eminence
they maintain posterior contact for longer than flat planes
monoplane anterior rules
- NO VERTICAL OVERLAP
- minimum of 1mm horizontal overlap
- tilt as indicated
- NO BALANCE - freedom of movement
anatomical anterior tooth arrangment rules
- 1 MM VERTICAL OVERLAP
- 1-2mm HORIZONTAL overlap
- tilt as indicated
- potential for balance
retromolar pad height if useing anatomical?
1/2
starts at 1/2 and ends at 2/3–due to the curve of spee
retromolar pad height if using curved posterior?
1/2
posterior crest of ridge on mandible relation to teeth placemtn?
the lowers central fossas are CENTERED to the posterior crest of ridge line
how are upper posteriors set in monoplane?
SLIGHTLY BUCCAL to the lowers – to porevent cheek biting
what is contacting in the posterior in a lingualized set -up on a curve?
maxillary posterior teeth are set with the lingual cusps in contact with the mandibular central fossae and the maxillary buccal cusps slightly out of contact
resoprtion of the ridges in general (no prosthesis placed yet)
the maxillary resorbs up and back
the mandible resorbs down and forward
how would natural occlusoin design in a complete denture affect bone loss? incisal guidance? canine guidance?
incisal guidance – both dentures to move. – increased anterior resorption with the anterior ridge acting as the fulcrum
with canine guidance – the dentures will also move and the single anterior point will act as the fulcrum causing resorption
fixed occlusal facotrs
Centric Relation
H condylar inclination
V condylar inclination
Alterable occlusal factors
- H overlap of anterior teeth
- V overlap of Ant teeth
- Cusp height of posterior teeth
- Curve of plane
curve a-p is called?
curve lateral called?
spee
wilson
3 occlusal schems
- ANATOMICAL - curved plane + cusped teeth
- MONOPLANE OR LINGUALIZED
a. flat teeth curved plane
b. flat teeth with flat plane
define monoplane occluson
an occlusal arrangement wherein the posterior teeth have masticatory surfaces that lack any cuspal height
define lingualized occlusion
described by howard payne in 1941- this form of denture occlusion articulates the MAXILLARY LINGUAL CUSPS WITH THE MANDIBULAR OCCLUSAL SURFACES IN CR AND EXCURSIONS so that the cutting edge is on the maxilla and the food table is on the mandible.
define anatomical occlusion
an occlusal arrangement for dental prostheses wherein the posterior artificial teeth have masticatory surfaces that closely resemeble those of the natural healthy dentition and articulate with similar natural or artificial surfaces
how to increase horizontal overlap in wax
do’s and don’ts
translate the mandibular horizontally (push back) – do not tip or retrocline
how to decreasr vertical during protrusive movements to limit anterior guidance? when in wax? when in denture?
denture = ware facets
wax = move down central anterior on the bottom vertically
How does monoplane set up meet the 4 major rules of denture occlusion?
- Area A is controlled clinically
- Area B is controlled in the lab – denture rules 1, 2,and 3 (no anterior contact in CO no incisal guidance and no canine)
- Max contact of posteriors in CR
- +/- curves (spee, wilson) to allow for control of excursions by condyles
advantages of monoplane occlusion
- easiest to set up
- potential to place least harmful forces on ridges
- best for poor quality of ridges
- can be used for class I II and III
disadvantages for monoplane occlusion
- chewing efficiency- conflicting
- pt. must be coached to chew on both sides - simultaneous
- easthetics are compromised
lingualized occlusion - general
flat lowers with a upper functional lingual cusp
what becomes ‘better’ when go from complete monoplane to a lingualized set up
chewing efficiency is improved
esthetic compromises improved because of the buccal cusps on maxillary teeth + chewing may get better because of that as well
what does balanced occlusion REQUIRE
- absence of anterior contact in CO
- Absence of incisal guidance in protrusion
- absence of canine guidance in lateral
- ** PRESENCE of compensating curves – curves allow for balance
what does monoplane teeth with curves allow us to do? what does it componsate for?
- allows us to compensate for anterior eshetic issues of monoplane set ups (before we did not have the ability to have anterior overlap)
- so it allows for anterior (vertical overlap)
- introduces the curves of spee and wilson so we are able to produce BALANCED OCCLUSION – curves give us balance
do you have to have cusps for balanced occlusion?
no- just need to have curves
Major rules/ points in balanced occlusion
- bilateral POSTERIOR CONTACT IN
- CO
- Lateral
- Protrusion
anterior contact in CO or lateral in balanced occlusion?
NO
when is it optional to have anterior contact in denture occlusion?
IN PROTRUSION
- anteriors MAY touch wit bilateral posterior in contact
- anteriors MAY NOT TOUCH WITHOUT POSTERIORS IN CONTACT
Definition of compensating curve
curve in the OCCLUSAL plane that compensates for the curve of the anterior eminence
curved planes maintain the POSTERIOR CONTACT FOR LONGER THAN FLAT PLANES
does balancing side open up in balanced occlusion?
NO
advantages of monoplane denture with curves
basic disadvantages?
- allows for more esthetic vertical and horizontal placement of mandibular anteriors – can get overlap
- may allow LIMITED ability to incise food
- may give better support and less movement during posteior occlusion due to balance
- when done properly, supports joint movement and may lessen stress on the TMJ
disadvantages :
- deep overbites still a problem
- difficult adjsutments – have to do a clinical remount
- if not done right - can increase denture movement and bone loss + wear of TMJ
what is the type of denture occlusoin recommended for a two implant retained mandibular overdenture?
lingualized (anatomical maxillary 20 degree molars) against monoplane mandibular teeth with curves
in lingualized occlusion what is the relationship of the crest of ridge on mandible
buccal cusps are STILL CENTERED – we are not moving teeth in - more refers to the maxillary lingual cusps
relationship of the crest of ridge on mandible in anatomical tooth set up?
the mandibular are set lingual so the buccal cusps are set centered over the crest of ridge (vs previously the fossa was over the crest of ridge)
posterior teeth in anatomical shift where?
lingually
objectives in balanced denture occlusion?
options to achieve?
- prevent anterior contact as long as possible
- maintain posterior contact as long as possible
options: Increase horizontal decrease vertical increase cusps increase curves
differences in overlap both vertical and horizontal in monoplane and anatomical
MONOPLANE :
1. NO VERTICAL overlap
2. minimum of 1mm horizontal overlap
+ no balance
ANATOMICAL
1. 1mm vertical overlap
2. 1-2 mm of horizontal overlap
+potential for balance
where do you start and end the occlusal plane when setting up for anatomical? for monoplane
ANATOMICAL: START :1/2 – because set curve up to 2/3 and cannot be higher than this– end higher due to the curve of spee
Monoplane – start and end at 2/3
how do we arrange the posteriors in anatomical - 3 general guidelines
- with crest of ridge
- retormolar pad
- overlap
Most common lingualized occlusal options in terms of degrees of teeth
Max = 10 or 20
MAnd = 0 or 10
how do you set up monoplane posterior? describe order
A-B-C(lower posterior), D
the lower central fossa are centered over the ridge and we are setting ONE SIDE/TOOTH AT A TIME- to maintain VDO and occlusal plane – the ENTIRE surface of the monoplane tooth must touch the plane
when do you stop setting teeth in the posterior?
end before the ascending ramus — only as many that can fit on the occlusal plane
orientation of the upper posterior in relation to the lower posterior in monplane? what does this prevent?
slightly buccal to the lowers
prevents cheek biting
what is holding VDO while you are setting a quadrant of posterior teeth?
PIN – never take pin off articulator
what are the implications of edge to edge in the posterior?
cheek biting will occur
‘reveal’ in monoplane lingualized in posterir?
1-2 mm horizontal overjet of the posterior teeth
upper is about 2-3 mm B to lower
describe relationship between the max and mandibular posteiror first molars in lingualized occlusion
the maxillary lingual cusp will occlude in the central fossa of the mandibular cusp - which is centered over the ridge
the maxillary buccal cusps will be slightly out of contact
for monoplane or lingualized where is the mandibular relationship to crest of ridge?
it is centered
3 curves in anatomical set up
- spee - anterior / posterior
- wilson - buccal.lingual
- facially - 5 degree - arch as it wraps – it aligns the heights of contour
anatomical posterior upper central fossa is centered where?
over the lower crest of ridge line – matching up the buccal cusps of lower into upper central fossa
the buccal cusp of maxillary will line up with the line we made 3mm buccal to the lower crest of ridge
what does placing the anatomical set up lingual to the crest of ridge compensate for?
compensate for the increased lateral forces that occur during excursions
facial curve of the maxillary posteriors?
aligns the height of contour of the teeth
curve of wilson in terms of the curve of spee
lingual curve od spee MINUS the buccal curve of spee
placement of maxillary first molar in relation to the occlusal plane
only the mesiolingual cusp will touch the plan
we tweek this tooth UPWARDS * not completely perpendicular to the occlusal plan like the bicuspids – long axis is tilted on molar
key tooth in lower arch anatomical?
lower first molar – then after we set this check excursion
*percise intercuspation in centric will facilitate intercuspation in eccentric
is the lingualized monoplane we set up an inter-cuspating occlusion?
NO – it is a non-intercuspating occlusoin using 0 degrees lower and 20 degrees upper
can a denture have an esthetic vertical overlap?
yes - as long as it has compensating curves or cusped teeth and/or curved planes are used
how to decide whether to use flat or cusp teeth? what is the check list?
1ST= CONDITION OF THE RIDGE
2ND=A,B, C checklist A= angles class B- Bruxism C= coordination (reproducibility) -- more freedom in eccentric movements
what will decrease the chance of increases in pressure with denture occlusion?
having NO anterior contact in CO
how to slow the rate of bone loss?
- prevent anterior occlusion by A. increasing horiztonal and B. decreasing vertical
- by maintianing posterior occlusion
by A. increasing cusp and B. increasing curve
