Final Flashcards
What is acrylic?
colorless pungent acid
What is resin?
natural or synthetic that form plastic materials after polymerization
Benefits of using polymethylmethacrylate (PMMA)
- excellent esthetic properties
- adequate strength
- low water absorption
- low solubility
- non-toxic/low allergenicity
- easily repaired
- reproduces detail accurately
- simple molding & processing technique
What is the best resin for dentures?
PMMA
What are the 5 ingredients of PMMA?
- liquid monomer - methyl methacrylate
- powdered polymer - polymethyl methacrylate
- plasticizer - dibutyl phthalate
- initiator - benzoyl peroxide
- pigments
What are the 3 parts of the PMMA liquid?
- mehtyl methacrylate
- glycol dimehtacrylate (cross linking)
- hydroquinone (inhibitor for incr shelf life
What are the three acrylic resin types?
- Heat cure
- Chemical cure
- Light cure
Write out the 12 step denture process
- Oral Exam, Tx Plan, prelim impressions
- Make custom trays on prelim casts
- Border molding and 2ndary impressions
- Master casts, record bases and occlusion wax rim (place post palatal seal on master casts, cut notches on wax rim for CR record)
- maxillo-mand relations, teeth selection (facebow transfer)
- arrange max & mand ant teeth
- anterior trial placement
- arrange max and mand post teeth
- trial placement in wax and pt approval (make new interocclusal/CR record and check on articulator)
- process dentures, lab remount
- clinical remount, occlusal corrections, insertion
- post insertion recalls
What is OVD?
distance between two points while in occlusion
What is IOD?
space between teeth when in physiologic rest position
What is RVD?
distance between two points when in phys rest position. OVD + IOD = RVD
What position is preferred because it is repeatable?
CR
Without _______________ the teeth will look fake.
buccal corridor
Do teeth touch when swallowing? When speaking?
Swallowing: yes
Speaking: no
Should the mandibular incisors be visible behind the lower lip?
slightly
How much of the maxillary incisors should show below the upper lip?
1-2 mm
How high up the rm pad should the occlusal plane be?
2/3
Maxillary post teeth should parallel what plane?
ala-tragus line (camper’s plane)
What is over open?
when teeth occlude too early (mandible and maxilla are still “open”) OVD too large
What is over closed?
when teeth occlude too late, speaking space is >3mm (maxilla and mandible are too closed)
What causes internal porosity?
When temp inside flask gets above 100 C. (monomer melts at 100.8)
Main diff between heat activated and autopolymerizing resins?
Method of activation of the initiator benzoyl peroxide
Why is heat activated better than autopolym resin?
- greater degree of polymerization
- better color stability
4 uses for tissue conditioners?
- prevent or treat chronic denture soreness
- stabilize temporary record bases
- stabilize immediate dentures during healing
- Final impression material for functional impressions
Main disadvantage of metal base dentures?
difficult to reline
What is the purpose of relining?
produce a better fitting intaglio surface without affecting the OVD
What are 4 reasons for tissue changes?
- stresses of daily function
- change sin general health status
- hereditary factors
- defects in dentures
What is a static impression? (closed mouth technique)
- pt occludes at OVD
- functional movements made with tongue
- removed moments later
- polysulfide, PVS, polyether, etc
When is the posterior palatal seal placed?
BEFORE PROCESSING
What is combination syndrome?
maxillary complete denture is opposed by mandibular anterior natural teeth
- maxillary anterior tissue is mobile or hyperplasia
- inflammatory palatal hyperplasia (IPH)
- maxillary tuberosities enlarged
- mandibular posterior bone resorption
- mandibular anterior teeth supraerupted
When do you need to “reduce, restore, or remove”?
When leveling the occlusal plane with combination syndrome
Main advantages of overdentures?
- support
- stability
- proprioception
- psychological benefit
Know the many disadvantages of overdentures.
Look them up
What factors lead to abutment tooth loss in overdenture pts?
- after 5-6 years 10% of abutments lost
- perio disease, caries, endo complications
- motivation for hygienic care - mechanical brushes
- Fl2 gel for daily application
Failures of Occlusal Errors (After processing)
- inaccurate max-mand records by dentist
- ill fitting temporary record bases
- change of OVD on articulator
- incorrect arrangement of post teeth
- heat generated when polishing dentures
- **failure to close flask completely during processing
- **too much pressure in closing the flask
- **resin shrinkage upon polymerization
You need new ______________ and ___________ at the insertion appointment.
- interocclusal records
- clinical remount
How long should the pt leave out old dentures before trying in the new dentures?
24 hrs
What is the PIP sequence?
- Dry denture
- thinly brush on pip
- seat denture w/ pressure on 1st molar region
- remove immediately
- inspect and adjust bearing surfaces as necessary
What is disclosing wax used for?
check for overextension of denture border
What are three causes of gagging?
- palate excessively thick
- palatal extension too long
- lack of tongue space
7 causes of occlusal errors
- resin shrinkage when processes
- ill fitting temp record bases
- change of OVD on the articulator
- inaccurate max-mand records by dentist
- incorrect arrangement of teeth
- overheated when polished
- water absorption (expands 1-3%)
What % of function do denture teeth have compared to natural teeth?
20%
What is the purpose of the cotton rolls during the clinical remount?
seating the posterior palatal seal and deprogramming the mandible for CR
What are the 5 advantages of a clinical remount?
- reduces pt participation
- dentist sees better what to do
- stable working foundation (base not shifting on tissue)
- absence of saliva (better for articulating paper)
- grinding may be done away from the pt
What three aspects of occlusion are desired after the clinical remount?
- simultaneous contact of all posterior teeth in returded mandibular position
- absence of contact on anterior teeth
- absence of defective interferences in eccentric movements
Along with occlusion, base contours, and posterior palatal seal, what may cause loss of retention?
- teeth not in neutral zone
- overextension or under extension
- salivary flow and character
Numbness or burning in the anterior papilla is a sign of……
pressure on incisive papilla
Numbness or burning in lower premolar areas is a sign of……
pressure on mental nerve
4 manifestations of tissue trauma
- hyperemia
- inflammation
- ulceration
- pain
Describe the process of making a conventional immediate denture
- remove posterior teeth (let heal for 6-8 weeks and make denture)
- extract anterior teeth at denture insertion appt
- denture is relined after tissue is done healing
one total denture
Describe the process of making an interim/transitional immediate denture.
- all teeth removed at once and interim denture is worn while tissues heal.
- Once tissues are healed, new permanent denture is made.
What are the 7 steps for immediate dentures?
- Exam/Dx/Tx Plan
- Preliminary Impression
- Secondary Impressions (custom impression tray, combination technique)
- Maxillo-mandibular relationship records
- Posterior “trial placement”
- Extractions - insertion
- Post-insertion care
After extractions for an immediate denture, how long should the pt wear their denture?
24 hours without taking it out
3 benefits and 1 exception of a two-phase surgery
Benefits
- simplifies clinical procedures
- reduces post-placement care
- improves denture comfort and retention
Exception
-with existing esthetic RPD, maintain posterior RPD abutment teeth
Major etiological factor of denture sequelae?
the presence of dentures
Ulcers on the crest of a ride indicate what?
On a vestibule?
- occlusal discrepancies
- overextended or sharp border
When treating ulcers on a denture pt, use PIP to adjust intaglio surface and do a clinical remount to find _______.
use a clinical remount to find centric relation
Inflammatory Papillary Hyperplasia is a symptom of what and caused by what two things?
- symptom of Combination syndrome
- caused by ill fitting denture and poor oral hygiene
A new denture pt presents with redness and fissures radiating from the angles of the mouth. What is this called and what are two main causes?
- Angular Cheilitis (perleche)
- Candida albicans fungal infection or staph aureus
- decreased OVD (over closed)
A pt presents with a little lip of tissue underneath their denture. What is this? Is this part of combination syndrome?
- Fibrous Hyperplasia/Epulis Fissuratum
- not part of combo synd
Is candida albicans more common in the maxillary or mandibular tissue?
maxillary
Candida has three presentations in pts with HIV. What are they?
- Angular Cheilitis
- Erythematous candidiasis
- Pseudomembranous candidiasis
What anatomical structures guide you in determination of the posterior extension of the max complete dentures?
hamular notch and fovia palatini
What anatomical landmark serves a guide for max anterior denture tooth placement?
incisive papilla (8-10 mm)
Wha tis the primary area of support for the mandibular complete denture?
buccal shelf
Wha is a posterior palatal seal placed in a max complete denture?
because the heat activated resin shrinks
Adhesion, cohesion, and intimate tissue contact contribute to complete denture ___________
retention
The clinical assessment of OVD is determined by a singular, scientific method.
false
clinically if CR is found to incorrect, you make a new intraoral record and remount which cast?
mandibular
At the trial placement appt, max incisors should contact the lower lip when which sound is made?
v or fricitive
When evaluating the trial dentures intraorally, you verify all the following except….
- tongue position
- centric relation
- esthetics
- OVD
tongue position
If teeth touch when speaking the s sound, what is the reason?
The OVD is too far open (over open) (insufficient IOD)
Why is a lab remount necessary after acrylic dentures are completed?
-correct processing error that affects the originally developed occlusion
How long should your pt leave their current dentures out of their mouth before new dentures are inserted?
24 hrs
When should you make clinical remount casts for occlusion refinement of the completed dentures?
before the denture insertion appt
what are advantages of performing a clinical remount procedure?
- a stable working foundation
- absence of saliva
How long is speaking impaired in a new complete denture patient?
less than a month (just over a week?)
How long is chewing impaired in a new complete denture wearer?
a couple months
A new denture pt should be appointed and seen when after denture insertion?
24-48 hrs
Common problems associated with a new mandibular complete denture are all except…
- esthetics
- discomfort
- poor retention
- lack of support
esthetics
After new complete denture insertion, alveolar ridge crest soreness is usually associated with _________
occlusion
what is the name of the resorption process that results in the maxilla becoming narrower and shorter?
centripetal
The biting force of natural dentition is ______ times greater than that of complete denture wearers.
5x
The most frequently selected natural tooth for an overdenture abutment is the ______
canine
T or F: a tissue conditioner can be used as a permanent denture liner.
False
The name of the process to replace the entire denture base is ____________
rebasing
The error to avoid when relining a complete denture is _________.
increasing the OVD
