Occlusion (Lecture 2: Terminology and Anatomy) Exam 1 Study Guide
1. 1. the act of wearing or grinding down by friction;
2. the mechanical wear resulting from mastication or parafunction, limited to contacting surfaces of the teeth:
attrition
2. Attrition is the act of wearing or grinding down by .: friction
3. 1. the parafunctional grinding of teeth
2. an oral habit consisting of involuntary rhythmic or spasmodic nonfunctional gnashing, grinding, or clenching of
teeth, in other than chewing movements of the mandible: bruxism
4. 1. an eating away; type of ulceration
2. in dentistry, the progressive loss of tooth substance by chemi that do not involve bacterial cal processes
action, producing defects that are w depressions often in occlusal, facial and cervical areas:
edge-shaped
erosion
5. Which is softer, dentin or enamel? Why?: dentin
- dentin is composed of less hydroxyapatite compared to enamel --> more suscep- tible to demineralization
6. pH range for demineralization of hydroxyapatite: 3.5-5.5
7. critical pH (equilibrium) of hydroxyapatite: 5.5
8. resting pH of hydroxyapatite: 7.0
9. After sugar intake, what causes the demineralization of the tooth surfaces?-
: drop in pH as the bacteria in the mouth convert sugar to acid
10.How many minutes does it take for the saliva to buffer the pH and return back to a normal level?: 20-30
minutes
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, Occlusion (Lecture 2: Terminology and Anatomy) Exam 1 Study Guide
11.Where can selective demineralization be observed?: in cup like defects (pitting) in areas that do not
occlude against the opposing tooth
- areas covered by enamel or restorative materials are mostly unaffected
12.What is extrinsic erosion caused by? Which surfaces are affected?: ingest- ed acidic substances
- affects FACIAL & OCCLUSAL surfaces of teeth
- worse in the lower arch
13.What is intrinsic erosion caused by? Which surfaces are affected?: regur- gitated stomach fluids (reflux,
bulimia)
- affects LINGUAL & OCCLUSAL surfaces of teeth *** may be asymmetric as in the wear of GERD
14.Extrinsic erosion is worse in which arch?: lower arch
15.What type of erosion affects FACIAL & OCCLUSAL surfaces?: extrinsic erosion
16.What type of erosion affects LINGUAL & OCCLUSAL surfaces?: intrinsic erosion
17.Physical appearance of erosion defects: smooth and glossy
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1. 1. the act of wearing or grinding down by friction;
2. the mechanical wear resulting from mastication or parafunction, limited to contacting surfaces of the teeth:
attrition
2. Attrition is the act of wearing or grinding down by .: friction
3. 1. the parafunctional grinding of teeth
2. an oral habit consisting of involuntary rhythmic or spasmodic nonfunctional gnashing, grinding, or clenching of
teeth, in other than chewing movements of the mandible: bruxism
4. 1. an eating away; type of ulceration
2. in dentistry, the progressive loss of tooth substance by chemi that do not involve bacterial cal processes
action, producing defects that are w depressions often in occlusal, facial and cervical areas:
edge-shaped
erosion
5. Which is softer, dentin or enamel? Why?: dentin
- dentin is composed of less hydroxyapatite compared to enamel --> more suscep- tible to demineralization
6. pH range for demineralization of hydroxyapatite: 3.5-5.5
7. critical pH (equilibrium) of hydroxyapatite: 5.5
8. resting pH of hydroxyapatite: 7.0
9. After sugar intake, what causes the demineralization of the tooth surfaces?-
: drop in pH as the bacteria in the mouth convert sugar to acid
10.How many minutes does it take for the saliva to buffer the pH and return back to a normal level?: 20-30
minutes
1/4
, Occlusion (Lecture 2: Terminology and Anatomy) Exam 1 Study Guide
11.Where can selective demineralization be observed?: in cup like defects (pitting) in areas that do not
occlude against the opposing tooth
- areas covered by enamel or restorative materials are mostly unaffected
12.What is extrinsic erosion caused by? Which surfaces are affected?: ingest- ed acidic substances
- affects FACIAL & OCCLUSAL surfaces of teeth
- worse in the lower arch
13.What is intrinsic erosion caused by? Which surfaces are affected?: regur- gitated stomach fluids (reflux,
bulimia)
- affects LINGUAL & OCCLUSAL surfaces of teeth *** may be asymmetric as in the wear of GERD
14.Extrinsic erosion is worse in which arch?: lower arch
15.What type of erosion affects FACIAL & OCCLUSAL surfaces?: extrinsic erosion
16.What type of erosion affects LINGUAL & OCCLUSAL surfaces?: intrinsic erosion
17.Physical appearance of erosion defects: smooth and glossy
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