Local Factors

Question 1

bacterial dysbiosis and the host response in a susceptible host

who said it

Answer 1

Hajishengalis 2015

Question 2

Palatoradicular groove

Answer 2

A developmental, anomalous groove usually found on the palatal aspect of maxillary central and lateral incisors.

Question 3

Palatoradicular groove

Answer 3

Invagination of inner enamel epithelium and HERS

Groove goes from cingulum down towards root

Question 4

Palatoradicular groove Study

Answer 4

Kogon 1986

3k extracted teeth (USA)
prevalence: 4.6%

Question 5

Cervical enamel projection (CEP)

Answer 5

An apical extension of enamel, usually toward a furcation.

Question 6

Cervical enamel projection (CEP) etiology

Answer 6

A result of failure of HERS to disintegrate and detach from the dentin matrix during tooth development. HERS cells have the potential to differentiate into ameloblasts which in turn can lead to the production of enamel below the CEJ, which might extend to the furcation area.

Question 7

Cervical enamel projection (CEP) study

Answer 7

**Bisada & Abdelmalek 1973
**
n= 1138 Egypt
2 Md molar (15%)>2 Mx molar (9%)> 1 md molar (8%)>1 mx molar (3%)

Hou and Tsaid 1987 had prevalence >50%, selection bias

Question 8

CEP treatment

Answer 8

Resective therapy: keep it to avoid root hypersensitivity
**Regenerative therapy: **Remove it otherwise, no new attachment

Question 9

CEP classification

Master and Hoskins 1964

Answer 9

• Grade 0 - no CEP
• Grade I – discrete extension of CEJ toward the furcation
• Grade II - CEP is closer to furcation, but without invasion
• Grade III - Enamel progresses into the furcation area

Question 10

Calculus

Answer 10

Calculus is NOT the etiology of periodontal disease; it is a local contributing factor.

Question 11

Calculus attachment (Zander 1953)

Answer 11

1. Cementum resorption
2. Microscopic irregularities
3. Secondary cuticle
4. Penetration (refuted by electron microscope study by Canis 1979)

Usually a combo of the above

Question 12

Calculus composition

Answer 12

Young (<1 year): brushite
Old: Whitlockit (mineral from calcium phosphate) and HA (Schroeder and Babauer 1966)

Mineral content of supraging 37%
Minteral content supging: 58% (Roberts-Harry and Clerehugh 2000)

Question 13

Listgarten and Ellegaard 1973

sterile calculus, electron microscope study

Answer 13

sterile calculus allows for regular attachment to JE via hemidesmosomes

Question 14

Allen and Kerr 1965

Guinea pig study

Answer 14

Sterile calculus injection caused foreign body reaction, not perio; non-sterile calculus caused inflammation

Question 15

Enamel pearl

Answer 15

Focal spot of enamel formed apical to CEJ (not connected)

Question 16

Enamel pearl etiology

Answer 16

Failure of HERS to disintegrate from dentin matrix.

Question 17

Moskow and Canut 1990

Enamel pearl

Answer 17

Review of 9 articles

Prevalence 2.6%

Question 18

Root concavities

Question 19

Root concavity percentages

Answer 19

Question 20

Furcation area

Bower et al 1979

Answer 20

81% of furcation entraces <1mm
58% <0.75mm

Blade of smallest gracy is 0.75mm

Question 21

Bifurcation ridges

Answer 21

Normal anatomical, sharp ridge spanning across the middle furcation that connects the inner surfaces of the buccal to lingual or mesial to distal roots.

Question 22

Bifurcation ridge study

Answer 22

Everett et al 1958

prevalence 73% 1 md molar

Question 23

Furcation trunk lengths

Oschenbein 1986

Answer 23

Type A: short
Max: 3mm ; Md: 2mm

Type B: medium
Max: 4mm ; Md: 3 mm

Type C: Long
Max: 5mm ; Md: 4 mm

Question 24

Furcation trunk lengths

Answer 24

Dunlap and Gher 1985:
Mx molars - Mesial: 3.6 mm; Buccal: 4.2 mm ; Distal: 4.8 mm

Mendelaris 1998:
Md molars: Lingual: 4.1 mm ; Buccal: 3.1 mm

Question 25

Accessory canals

endo connection

Answer 25

De Deus and Horizonte 1975

1140 extracted teeth

27% (17% apical, 8.8% body, 1.6% base of root)

Question 26

Cemental tear

Lin 2011

Answer 26

Etiology not elucidated
Most common:
* incisors (76% of tears)
* men (77.5%)
* >60 y/o (73%)

Associated with abscess formation, PD>6mm, positive vitality, attrition

Treated with SRP, endo, or exo

Question 27

Adjacent teeth (open contact)

Answer 27

Food impaction, plunger cusp

Jernberg 1982:
* increased PD and CAL at open contacts (minor clinical effect)

Question 28

Open contact classification (Hancock et al 1980)

Answer 28

1. Tight: definite resistance to passage of floss
2. Loose: minimal resistance
3. Open: no resistance

Question 29

Tooth crowding

Answer 29

Plaque accumulation from inadequate acces

Question 30

Root proximity

Answer 30

Less than 0.8 mm interradicular space

Question 31

Tal 1983

Root proximity

Answer 31

Infrabony pockets when interprox distance > 2.6 mm

Question 32

Trossello and Gianelly 1979

root proximity

Answer 32

Interraddicular bone <1mm in 12% of ortho treated pts

Question 33

Root proximity classification

Answer 33

Question 34

Adjacent 3rd molar

Answer 34

Causes periodontal risk to 2nd molars

Question 35

Kugelberg 1990

Adjacent 3rd molar

Answer 35

Defects distal to 2nd molars in pt.s ≤ 25 years or ≥ 25 years 4 years following extraction. Retrospective study

% >7mm distal 2nd molar defect:
<25y/o : 25% >25y/o: 52%

Question 36

Retention of hopeless tooth

Answer 36

No effect with perio therapy:
Wojcik et al 1992:
retained hopeless teeth did not affect adjacent teeth IF periodontal therapy given

Effect without perio therpay:
Machtei et al 1989:
Annual bone less was -3% vs. -0.23% if tooth extracted

Question 37

Subgingival margin

Answer 37

Newcomb 1974:
strong negative correlation between gingival inflammation and distance of crown margin to base of sulcus

Question 38

Overhanging restoration

Answer 38

Jeffcoat and Howel 1980:
* x-sectional study of 100 pt with amalgam overhangs and 100 pts without
* Medium or large overhangs resulted in more bone loss

Classification:
Small: <20% of interprox space
Medium: 20-50% of interprox space
Large: >50% interprox space