Removable Test 1 Flashcards
How many appointments required for Diagnostic Exam for prosth?
2 appointments
What 5 things are accomplished in the first prosth appointment?
- Thorough health history
- Preliminary oral cavity exam
- Dental prophylaxis
- Radiographic survey
- Accurate max and mand impressions
What are the 4 major patient psychological categories by Dr. MM House?
- Philosophical
- Hysterical
- Exacting
- Indifferent
Patient’s with Systolic pressure exceeding ____ or diastolic exceeding _____ should be considered to have a potentially serious medical condition indicating a medical consult?
130mmHg systolic
90mmHg diastolic
What are 2 oral conditions seen in uncontrolled diabetes?
- Small oral abscesses
2. Poor tissue tone
Diabetic patients can have what oral condition that can make prosthesis wear difficult as well as increase caries risk?
Reduced salivary output
Where can Paget’s disease can cause enlargements that can change fit of a prosthesis?
Maxillary tuberosities
Patient with this disease will show enlargement of the mandible which can change fit of prosthesis?
Acromegaly
What neurological disease causing rhythmic muscle contractions making prosthesis planning as well as wear difficult?
Parkinson’s disease
What is a disease with oral bullae showing first then moving onto the skin?
Pemphigus vulgaris
What is a consideration for material use when making a RPD for an epileptic patient?
All material should be radiopaque in case swallowed or aspirated during seizure
What 2 things are usually indicated with increasing age?
- Need for some type of prosthesis
2. Need for prescription or OTC meds that can affect dental treatment
What is the most significant side effect of antihypertensive drugs?
Orthostatic hypertension
What usually initiates bruxism?
Interceptive occlusal cotacts/occlusal permaturities
What are some physical characteristics to note during the interview?
- Neuromuscular/neuromotor deficits
- Length and mobility of lips
- Decreased vertical dimension of occlusion (VDO)
- Speech problems
What is the most important measure to minimize disease transmission between patients and dental care providers?
The routine use of gloves
Must custom trays, record bases, and occlusion rims be disinfected after construction?
Yes. Stewart’s says 2 minutes of sodium hypochlorite application
Impressions should be loosely wrapped in plastic and set aside for how many minutes after rinsing with water and disinfecting?
No less than 2 min
Casts should be poured no more than _____mins after removal of alginate from mouth?
12 mins
What are 3 responsibilities of the dentist to explain for patient oral hygiene?
- Signs and symptoms of disease
- Materials and techniques for proper home care
- Patient’s responsibility to prevent further dental disease
Which radiograph is essential for determining the crown-to-root ratio and the condition of the periodontal tissues?
Periapical
What radiograph helpful to identify interproximal caries on the remaining teeth?
Bitewing
Which radiograph is ideal for screening for pathologic conditions?
Panoramic
Is a panoramic radiograph adequate for the definitive examination of a RPD patient?
No
An RPD exam is considered incomplete unless it includes what?
Evaluation of accurate diagnostic casts
What items serve as blueprints for placements of restorations, recontouring of teeth, and the preparation of rest seats?
Surveyed and marked diagnostic casts
Casts are normally mounted and evaluated during which diagnostic appointment: first or second?
Second (get facebow record at second app)
What is the material of choice for diagnostic impressions?
Irreversible hydrocolloid/alginate
Is the accuracy of irreversible hydrocolloid affected by changes in the water-powder ratio?
No, will only change consistency and setting time
What type of measurement performed using a scoop, and is inaccurate because the powder can be loose or tightly packed within the scoop?
Volumetric measurement
What measurement technique is the preferred method for alginate powder?
Weight measurement
What alginate weight is used for most impressions?
28g
What amount of water mixed with the 28g of alginate powder?
68-72 mL
What is the manufacturer recommended temperature of water for alginate impressions?
22°C/72°C
What can increase the working time of alginate?
Refrigerate mixing bowl and water
What are 2 primary mechanisms of distortion of alginate impressions resulting in inaccurate diagnostic casts?
- Evaporation
2. Absorption of liquids/imbibitions
Evaporation does what to the alginate impression?
It causes it to shrink
What results in localized expansion of the completed impression?
Imbibitions
Should alginate impressions ever be wrapped in wet paper towel or immersed in a liquid and why?
No, such things carry a risk of imbibitions
What are 3 factors contributing to alginate sticking to teeth?
- Impression done after thorough polishing
- Teeth dry
- Repeated impressions
What are the impression trays of choice for RPD impressions?
Nonperforated metal trays
What is the most important factor in determining impression tray size?
Width of dental arch
There should be clearance of ___mm to ___mm between inner flange of tray and the facial surfaces of the remaining teeth and soft tissue?
5mm-7mm
What are 3 techniques to prevent gagging during impression making?
- Patient sits upright
- Max tray modified posterior to stop alginate flow down throat
- Use astringent mouthwash or cold water rinse immediately prior to making impression
When mixing alginate: should you add water to powder or powder to water?
Powder to water (water in bowl first, add preweighed powder to it)
What is the minimum time to spatulate alginate?
45 sec
What is the most consistent method for alginate spatulation?
Mechanical under vacuum (20lbs for 15 sec)
Stewart’s suggests making which impression first and why?
Mandibular. Less discomfort, increases patient confidence
The gelation of alginate impression material is complete within ___ min?
2-3 min
When should an impression be repeated?
When there are voids in critical areas
Stewart’s says to leave an alginate impression in the mouth how long after the loss of surface tackiness to allow development of additional strength?
2-3 min
The gel strength of alginate does what during the first 4 minutes after initial gelation?
It doubles
To ensure an alginate is ready to remove, what can be used to verify?
Small mound or original mix fractures cleanly with finger pressure
Should an impression be removed from the mouth with a rapid tug directed along the long axes of the teeth or with a slow rocking motion?
Rapid tug along long axes teeth
What is essential in all phases of RPD design and construction?
Cast with dense, abrasion-resistant surface
Surface hardness of a stone cast is directly related to what?
Compressive strength
Compressive strength of a stone cast is directly affected by what?
Water-powder ratio when cast is made
All gympsum products (both plaster and stone) require what water-powder ration?
18.61 mL to 100g powder
What is formed when water is added to powder for dental plaster or stone?
Calcium sulfate dehydrate
All gypsum products should be measured by ____ rather than by ______?
Weight rather than volume
Gypsum mixed how: water to powder or powder to water?
Powder to water (water in bowl first, then add preweighed powder to it)
What is adequate gypsum mixing time?
60-90 sec
What dental stone is indicated for diagnostic and master casts?
Minimal expansion. ADA type II or type IV stone
What is the pour technique for alginate impressions resulting in casts in which teeth and soft tissue areas are densest and most abrasion resistant?
2 stage pour technique
Why not do a single stage/inversion pour technique?
Water will rise to the surface. In this case it would be the teeth, making them brittle
In 2 stage pour, the initial pour is allowed to go to initial set, which is ____ min?
12-15 min
What is done with the initial pour cast after initial set, before putting on second pour?
Soak in clear slurry water for 4-5 min
What is a supersaturated solution of calcium sulfate made by placing chips of dental stone in water for 48 hrs?
Clear Slurry
What is the benefit of clear slurry soak of first pour?
Allows wetting of 1st pour without dissolution of stone
How is the 1st pour placed on the 2nd pour?
Inverted on the second pour and edges cleaned up with a spatula
How long after the first pour should the cast and impression be separated?
45-60 min
What is the maximum time alginate should be allowed to stay in contact with stone cast?
60 min
Should a cast be trimmed if it is dry?
No, should soak in clear slurry first
The base of a cast should be trimmed to what thickness?
10-13 mm thick at the thinnest point with occlusal plane parallel to the deck
Where is a mandibular cast thinnest, and where is a maxillary cast thinnest?
Mandibular thinnest in lingual sulcus
Maxillary thinnest at center of hard palate
How should the posterior surface of cast be related to midline of the palate?
Perpendicular to midline
Land area of ___ mm is trimmed around entire cast?
2-3 mm
Are anterior borders of max and mand casts trimmed the same?
No
How is the anterior max cast trimmed?
Angular, originates from canine area on each side and extends to a point anterior to central incisors
How is anterior mand cast trimmed?
Gently curves, originates from one canine curving around to the other canine
What is the most common cause of surface roughness of dental casts?
Adherence of alginate to enamel
Leaving alginate in contact with cast greater than 60 min after initial pour causes what?
Surface etching (soft, chalky surface)
What are the 3 phases of mounting a cast?
Orient maxillary cast to articulator condylar elements via facebow
Orient mandibular cast to maxillary cast via centric relation record
Verification