Date post: | 17-Aug-2015 |
Category: |
Science |
Upload: | arsalanhosseini |
View: | 38 times |
Download: | 0 times |
1
EDENTULOUS STATEBucher2013
Chap.1
Etiology: heterogeneous dental diseases ,culture ,financial,attitude
Prevalance : but partially dentate
EDENTULOUS STATE
1)Need for complete denture remain high
2)High percentage of older people be edentoulus
3)Impact of longivity on edentulism ?
4) Difficult treatment
EDENTULOUS STATE
Periodontium: hard CT& soft CT
Principal functions: 1)support
2)positional adjustmentSecondary & dependent function: sensory perception
SUPPORT OF NATURAL DENTITION
Quality : Mucosal vs periodontium
Quantity: max:22.96 vs 45cm²mand:12.25
denture-bearing area (basal seat) becomes smaller as ridges resorbs
mucosa :little tolerance /adaptability to denture wearing
Systemic diseases: Anemia, hypertension , diabetes , nutritional deficencies
Support for complete denture
intermittent , rhythmic and dynamic
greatest forces : mastication & deglutiton vertically in direction tongue & circumoral musculature: lower,longer,horizontally
Physiological forces
Increase steadily & abruptly return to zero magnitude , rise time , interval between thrust consistency , stage of chewing, dental status
Physiological forces
function :17.5 min per daymastication(9min) < deglutition
Parafunction : (grinding , clenching,bruxism)
occlusal forces
Natural dentition: 200 N
Complete denturers : max:60-80 N 5-6 times less
masticatory forces ~ type foodFood choice ~ tissue tolerance
Masticatory loads
The residual ridge consists of denture-bearing mucosa, the submucosa and periosteum, and the underlying residual alveolar bone
Residual Ridge :
Residual Ridges
Tensile compressive
Vertical & horizontal
1)Direct effect of loss of pdl
2)Poorly understood factors
Ridge Resorption
More rapid in ant.mand Functional movement may be a major cause(unproved)
"principles" of complete denture construction:
1)minimize the forces transmitted to the supporting structures
2) to decrease the movement of the prostheses
physical factors
1)maximal extension of the denture base(impression)
2) maximal intimate contact (impression)
3)frequent follow up(reline)
muscular effect(neutral zone) buccinator ,orbicularis oris,intinsic&extrinsic muscles of tongue
Psychological effect salaiva
retention
The edentulous state
Deteriorating adult dentition
Healthy adult
Developing dentition
Development & adaptation of the occlusion
16
it has been concluded that masticatory efficiency as low as 25% is adequate for complete digestion
of foods
Patients do not compensate for the smaller number of teeth by more prolonged or a larger number of chewing strokes
they merely swallow larger food particles
d
Loss of teeth
diminished masticatory efficency Restrict dietary choice
Systemic effect
• Quality of prosthetic service is related to
dentuer wearer masticatory performance
mandibular movement of dentate & denturers is similar treatment of partially edentulous and
edentulous patients:
chewing efficiency improve masticatory muscle activity
elevator muscle activity & occlusion phase
Chewing occurs chiefly in the premolar and molar regions
both right and left sides are used to about the same extent
the tougher the consistency the greater is the person’s preference for using the
premolar region
The end… Thanks for your patienceAny question? …
24