Epidemiology

Question 1

Periodontitis prevalence

Answer 1

~42% of US population >30y/o
11.2% global prevalence (severe perio)

Kassebaum et al 2014

Question 2

2017 AAP definition of periodontitis

Answer 2

Interproximal CAL at ≥ 2 non-adjacent teeth

OR

Buccal or facial CAL ≥ 3mm with PD > 3mm in non-interproximal surfaces in at least 2 teeth.

Question 3

Gingival Index

Loe and Silness 1963

Answer 3

Question 4

Plaque Index

Silness and Loe 1964

Answer 4

Question 5

Modified gingival index

Lobene 1986

Answer 5

Question 6

Community Periodontal Index for Treatment Needs (CPITN)

Ainamo 1982

Answer 6

CPITN probe: 0.5mm ball at tip, 3.5-5.5 mm markings

Used for PSR

Question 7

Perio prevalence; Eke et al 2018

NHANES study (2009-14)

Answer 7

• 42% of population has periodontitis (8% severe)
• Most prevalence in mexican americans, then black peorple
• prevalence increased with age
• more prevalent in active smokers, noncompliant pts
• More severe CAL: smokers, diabetics, lower SES

Question 8

Eke et al 2018 probe/perio classification

Answer 8

Question 9

Challenges of epidemiology studies in perio

Borrell and Papapanou 2005

Answer 9

1. Wide threshold in defining perio
2. Full mouth recordings vs partial (Ramfjord teeth: 3, 8, 12, 19, 24, 28)
3. x-sectional studies
4. Lack of longitudinal data
5. Large dataset management
6. Sample selection (NHANES reflects non-whites; NIDR is employed adults)
7. Sampling variation

Question 10

Ways to improve epi studies

2015 American & European periodontal epidemiology workshop

Answer 10

1. Study design should include non-response and drop-out
2. Full mouth probing protocol
3. Perio probe should be UNC15
4. Examiner reliability should be reported (kappa statistic)
5. Report all perio risk factors

Question 11

Kornman 1976

Answer 11

Question 12

Non-specific plaque hypothesis

Loesche 1976, Theilade 1986

Answer 12

Amount of bacteria determines pathogenecity and destruction of periodontium

Problem is amount of plaque did not correlate with amount of destruction

Question 13

Specific plaque hypothesis

Loesche 1976, Socransky 1998

Answer 13

Only a limited few bacterial species were capable of causing periodontal disease

Problem: not all could be cultivated, therefore bias to easily cultivatable bacteria

Question 14

Ecological hypothesis

Marsh, 1994

Answer 14

Ecological stress triggers a shift in the resident microflora

Should target host response in addition to bacteria

Question 15

Keystone pathogen hypothesis

Hajishengallis 2012

Answer 15

Host immunity plays critical role. Authors promoted term “dysbiosis”, meaning certain bacteria have the capacity to alter immune response, even if they exist in small numbers.

Question 16

Loe 1978

Periodontal disease progression

Answer 16

Compared two cohorts, Noreweigens (with annual recalls and 90% compliance) and Sri-Lankan laborers with no preventive or treatment

Mean CALoss:

Nor: 0.08 mm interprox; 0.1mm buccal
SL: 0.3 mm interprox ; 0.2 mm buccal

Question 17

Loe et al 1986

Sri lankan follow-up

Answer 17

Question 18

Ramseier et al 2017

Follow-up on Loe 1986 study

Answer 18

Moderate progression: 92%, Rapid progression 8%

CALoss <1.81 mm was 80%ppv for presence of at least 20 teeth at age 60

Question 19

Goodson et al 1982

22 patients followed monthly for a year

Answer 19

82.8% –> no change
11.5% –> became shallower
5.7% –> became deeper

Question 20

Socranksy 1984

Untreated perio patient disease progression

Answer 20

CALoss of >2mm:

Baseline: 12%
3 years: 40%

Continuos model: some sites show progessive CALoss over time
**Random burst model: **activity at random on any site
Asynchronous multiple burst model: several sites show repeaeted bursts of activity, followed by inactivity

Question 21

Teles et al 2018

Answer 21

Question 22

Becker 1984

Rate of tooth loss

Answer 22