Midterm Review Flashcards
What percent of adults (ages 20-64) have missing teeth (not including 3rd molars)?
52% of adults are missing teeth (excluding 3rd molars)
What is associated with increasing the probability for tooth loss?
Tooth loss increases with diabetes, and increases indirectly with education and income. Tooth loss varies by ethnicity Tooth loss is unaffected by gender
What behaviors decrease tooth loss predictably?
Brushing and Flossing decrease tooth loss predictably
What is the difference between masticatory ability and masticatory efficiency?
Masticatory ability is focused on patients’ reported psychological assessments (subjective assessments) – *self assessment of chewing ability is more optimistic than the results of objective tests* Masticatory efficiency is based on objective assessments
What are the problems noted by partially edentulous patients regarding their teeth?
Problems noted are psychological – patients feel uncomfortable, uptight, embarrassed and self conscious
What does not bother partially edentulous patients about their teeth?
Patient’s report that partial edentulism does NOT affect diet, speech or function, and is NOT painful and does NOT interrupt meals
What macro nutrient do partial edentulous patients struggle acquiring?
Fiber deficiency
What vitamins or minerals do partial edentulous patients have a deficiency in?
Folate, Magnesium and Iron deficiency
What foods do partial edentulous patients routinely not eat?
Partial edentulous people eat just a little less of dark green and orange vegetables, less legumes and less whole grains
What number of missing teeth is cited as “problematic” in chewing?
20 teeth or less is usually considered the baseline of disease by NHANES, WHO and Witter&Steele
Does partial edentulism increase the fraction size of the food boli, and therefore does partial edentulism with 10 or more missing teeth impact patients’ masticatory efficiency?
Yes! It has been shown that missing functional teeth leads to 50% of the reason why food isn’t getting fractioned down in partial edentulous patients
What are the contemporary common solutions to partial edentulism?
- Removable Partial Denture 2. Fixed Partial Denture – Bridge, Cantilever, Maryland Bridge 3. Single or multiple unit dental implant
What are the contemporary common solutions to partial edentulism?
- Removable Partial Denture 2. Fixed Partial Denture – Bridge, Cantilever, Maryland Bridge 3. Single or multiple unit dental implant 4. Do nothing
What are the specific and general problems with the current solutions to partial edentulism?
RPD = functional and social limitation, and some psychological discomfort but no physical pain. low satisfaction, increased caries and perio risk FPD = No functional limitation, some pain, but improvement with psychological discomfort, physical and social limitation. General problems: Intervention does not fix patients ability to speak, taste, select food and won’t help people feel more satisfied with life/able to function. However, intervention does relieve patient’s psychological discomfort, self consciousness, feelign of tension
Describe the state of literature regarding the quality of evidence in determining the value of one prosthetic over another.
There is insufficient evidence to recommend one prosthetic intervention versus another
Describe “heuristic” and what a common heuristic outline of prosthetics would look like.
Heuristic means going with one’s gut intuition RPD: okay function, 5-7 years longevity FPD: good satisfaction, increased caries and perio risk – good function, 7-10 years longevity Implants: costly, great function, good longevity, high satisfaction, low risk for caries and perio
How do removable partial dentures effect those on the island of disease and how should dentist’s best help those with partial edentulism who are receiving RPDs?
RPDs do not cause any adverse peridontal reaction, provided that perio health has been established and maintained + great oral hygiene. Caries risk increases. –> frequent recalls and prosthetic maintenance are essential for good long term prognosis
What is do Kennedy Class 1, 2, 3, and 4 look like?
Class 1: Bilateral edentulous areas posterior to remaining natural teeth Class 2: Unilateral edentulous area posterior to remaining natural teeth Class 3: Unilateral edentulous area with natural teeth remaining both in front and behind it Class 4: A single edentulous area that crosses the midline, anterior to remaining natural teeth *no mods*
What are modifications spaces and how do you classify these partial edentulous cases?
Modification spaces are edentulous areas other than those that determine the classification. Classified by the number of edentulous areas not the number of teeth missing. The most posterior edentulous area always determines the classification. 3rd and 2nd molars are not considered in the classification, unless they are going to be used as an abutment
What are the simple machines?
Wedge, lever, inclined plane
What are the differences between the lever classification?
Class 1: (Force) (Fulcrum)(Resistance) Class 2: (Force) (Resistance) (Fulcrum) Class 3: (Resistance)(Force)(Fulcrum)
How can you increase or decrease forces when using levers? 3 ways to decrease force exerted on resistance?
Move resistance further from the fulcrum, move the force closer to the fulcrum or move the fulcrum closer to the force
Draw all the lever classifications in an RPD
Are you able to identify the path of insertion, heights of controur, and the undercuts using a surveyor?
Yes
THe undercut is below the height of contour
Use a pencil to mark HOC and a disc to find undercut
What is stability compared to rentention and support?
Stability is in the horizontal plane – destabilizing forces act to dislodge the prosthesis in a horizontal dimension (something about the perpindicular walls of the HOC that help with stability)
How do guide planes contribute to stability?
The guide plane element is sitting against the HOC, which is perpendicular to the destabilizing forces so it is really uselful for reducing destabilizing forces
How do reciprocal arms and retentive arms contribute to stability?
The reciprocal arm sits against the HOC and can resist horizontal forces by transferring the forces to the the wall of the tooth which is perpendicular to destabilizing forces
The Retentive arm touches above, on and below the HOC so it is useful in reducing destabilizing forces, even though not all teh stabilizing walls are perpendicular to the forces
How do major connectors contribute to stability?
Rigid major connectors allow destabilizing forces to be spread across many teeth which push back on the destabilizing forces to increase stability
How do rest seats contribute to stability?
Metal rests sit in rest seats in teeth, and are roud on the contacting surface (to lessen the stress in enamel), They have a minor horizontal component, and actually, destabilizing forces will lift the rest from the rest seat.
How do acrylic bases contribute to stability?
Acrylic bases are useful in adding stability, but like rests seat, will lift from the ridge walls when horizontal/vertical forces are applied.
Name the major connectors and describe their differences
We only need to know the lingual bar, and the lingual plate
What is the primary plane used in considring destabilizing forces?
The Horizontal Plane – why? because it shows ALL horizontal movement
What is retention’s role in the control of prosthetic movement?
Retention – forces acting to displace the prosthesis along the path of insertion
A retainer is any unit of a RPD that engages the abutment tooth or implant to resist displacement of the prosthesis away from basal seat tissues
How do retentive arms, reciprocal arms, and guide planes contribute to retention?
The guide plane, the reciprocal arm, and the retentive arm work to encircle the tooth (more than 180 degrees) to increase retention
What is the difference between circumferential and bar clasps?
Circumferential clasps approach the undercut coronal to the HOC and pull the clasps over the HOC = engaging the undercut –> provide more stability and less retention (these are best used in kennedy class 3 cases and in mod spaces)
Bar clasps approach the undercut apical to the HOC and push the clasp over the HOC = non engaging –> provide less stbaility (best used in Kennedy class 1,2,4)
Does changing the path of insertion change undercuts?
Yes
What is support’s role in the control of prosthetic movement?
The denture base and the rests support the artifical teeth and thererfore receive the functional forces form occlusion and transfers forces to supporting oral structures –> without support, pain and damage to oral structures would take place
What is the difference between a tooth supported partial and a tissue supported partial?
Tooth born partials are far easier to construct – it is hard to construct a distal extension, because it needs a lot of support from the underlying tissues
Maximum tissue support occurs by using broad, accurate bases which spread the load over the entire area
What are the depth cuts for rest seats (anterior and posterior) that provide fundamental support?
Anterior: only for maxillary anteriors, do not do on mandibular
- Lingual: 2.5 to 3 mm MD
- Incisal: broadest at the lingual
- Proximal: correct taper, 2 mm labiolingually, and minimum 1.5 mm inciso-apical
Posterior: Rounded triangular in shape, spoon shape floor
- 2.5 mm MD from marginal ridge
- 2.5 mm labiolingually
- Floor of rest should be about 2 mm at the apex of triangle and 1.5 mm under the marginal ridge
How thick is the thinnest portion of the trimmed cast, when measuring from the bottom of the base of the cast to the closest portion of the top surface?
12-15 mm
What is the expected thickness for the land area in a trimmed cast?
2-3 mm
What 3 anatomical landmarks are noted on the U of U trimmed cast hand out and required for the mandibular cast?
Retromolar pad, vestibule ??
What can you add to a “flinker” to increase retention?
A friction inducing element on teeth
What could be added to a “flinker” to increase stability?
Anything that touches a vertical wall
What could you add to a “flinker” to increase support?
Any portion of the RPD touching horizontal surfaces
True or False: Classification should follow rather than preced any extractions of teeth that might alter the original classification
True… classification should follow rather than preced any extractions of teeth that might alter the original classification
True or False: The most posteior edentulous area always determines the classification (except in class 4 cases)
False (??? idk why)
What portion of people aged 40-65 are NOT missing teeth (excluding 3rd molars)
33% of people aged 40-65 are NOT missing teeth (excluding 3rd molars)
True or False: Most people in America are partially edentulous
True, most people in America are partially edentulous
What benefits to partial dentures do patients see?
Feel less tense, less self conscious, less embarrassment
What do partial edentulous patients typically eat less of (may be due to effect of partial edentulism on grinding foods)?
Eat less whole graines, dark and oragne vegetables, and legumes
What factors are associated with partial edentulism? What factor is not associated with partial edentulism?
Systolic blood pressure, education level, sedentary lifestyle, and obesity are associated with partial edentulism
Gender does NOT affect partial edentulism
True or False: There is reasonably good data to show that partial dentures cause better general health
True, there is reasonable good data to show that partial dentures cause better general health
What do our interventions for partial edentulism NOT do for patients?
Does not fix patient’s ability to speak or taste (may make it worse), do not improve patient’s food selection, and do no help people feel more satisfied with life or more able to function
What do our interventions for partial edentulism do for patients?
Help FPD wearers and middle aged patients feel less irritable with others and more able to do their jobs, make people more relaxed and less embarrassed, and reduce self consiousncess and feeeling of tension about the teeth
True or False: Strong scientific evidence suggest implants over RPDs
False, there is not strong evidence that suggests implants over RPDs
True or False: As long as the periodontium and the removable partial denture are maintained, the periodontium are just fine with RPDs
True, As long as the periodontium and the removable partial denture are maintained, the periodontium are just fine with RPDs
True or False: Tooth loss is a causal link to many systemic disease
False! tooth loss is NOT a causal link to many systemic diseases
From highest risk to lowest risk, what is the caries risk of the following interventions: No treatmnet, RPD, FPD, Implant
RPD, FPD, Implant, no treatment
What creates more retention, a clasp being pulled over a HOC or a clasp being pushed over HOC?
A clasp being pushed over HOC
True or False: Support can be defined as a resistance to occlusal forces
True
Which classification will have the lesat movement?
Kennedy Class 3
Which clasp material deflects (wiggles) the least?
Cobalt chrome cast clasp
What clasp material requires the biggest undercut?
Wrought wire