This document discusses methods for measuring various oral health conditions in epidemiology. It covers malocclusion measurement tools like Angle's classification and the Index of Orthodontic Treatment Need (IOTN). For oral cancer, it discusses prevalence, survival rates, and risk factors. Cleft lip and palate occurrence is expressed as proportions or rates. Quality of life measures like the Oral Health Impact Profile (OHIP) and General Oral Health Assessment Index (GOHAI) are presented.

1. Measuring other conditions in
oral epidemiology
PDS 372

2. Lecture outline
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Malocclusion
Oral cancer
Cleft lip and palate
Oral health and quality of life

3. Learning objectives
• At the end of this lecture, the student will:
– Learn about different methods of measuring
other dental conditions in oral epidemiology
– Learn about how to measure these conditions
in a public health perspective
– Understand the concept behind quality of life

4. Malocclusion
• Edward H. Angle,
• The first simple
classification system
for malocclusions
• Based on the first
molar as the key to
occlusion.
• Classification system
is still in use today for
orthodontic diagnosis
The father of modern
orthodontics
1855-1930

5. Malocclusion
• Difficult to measure
• Angle’s classification is a nominal scale
• The malalignment index assess rotation and
tooth displacement
• Occlusal Feature index records crowding,
cuspal interdigitation and vertical and horizontal
overbite
• The Handicapping Labio-Lingual Deviations
(HLD), assesses treatment needs

6. Malocclusion
• Occlusal index:
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Dental age
Molar relation
Overbite
Overjet
Posterior crossbite
Posterior overbite
Tooth displacement
Midline relations
Missing permanent maxillary incisors

10. What is IOTN?
• The Index of Orthodontic Treatment Need
(IOTN)
• It combines both functional and aesthetic
measures
• Used to assess the need and eligibility of
children under 18 years of age for orthodontic
treatment
• IOTN is an objective and reliable way for
specialists to select those children who will
benefit most from treatment and is a fair way to
prioritise limited resources

11. IOTN
• The Dental Health Component (DHC) has 5
Grades
– Grade 1 is almost perfection
– Grade 2 is for minor irregularities
– Grade 3 is for greater irregularities which normally do
not need treatment for health reasons
– Grade 4 is for more severe degrees of irregularity and
these do require treatment for health reasons
– Grade 5 is for severe dental health problems

12. IOTN
• The Aesthetic Component (AC)

13. Malocclusion
• Peer Assessment Index (PAR)
– Dental anomalies in a single score
• Index of Complexity, Outcome and
Need (ICON)
– Correlate well w pt perception of esthetics,
function, speech and need for Tx.
• FDI attempt to unify indices: failed
• Attention towards aesthetic vs. function
• Dental Aesthetic Index (DAI)

14. Malocclusion
• WHO in the pathfinder survey suggests using
DAI criteria in the following conditions:
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Missing teeth
Anterior crowding
Anterior spacing
Diasteimas
Largest irregularities in front teeth
Overjet and overbite (anterior)
Molar relation

15. Oral cancer
• The occurrence is expressed as a
proportion or rates
• The age-adjusted rate of years of life lost
from oral cancer
• Five-year survival rates
– A 5-year survival rate of 67%
• Cancer data maintained in registries

16. Oral cancer

18. Oral cancer

19. Cleft lip and palate
• The occurrence is expressed as a
proportion or rates
• 1 infant in 700 births
• Congenital abnormality
• Supposed to be recorded on birth
certificates

22. Oral health and Quality of life
• Health measured instead of disease
• Difficult to measure health…..why? Difficult to
define
• Index for oral health
• Oral Health Impact Profile (OHIP)
– Measures the social impact of oral conditions
– 49-item scale ……….14-item scale
• General Oral Health Assessment Index (GOHAI)
– Geriatric Oral Health Assessment Index
– 12- item scale
– Assesses physical functions, psychosocial functions,
pain and discomfort

23. What is
Health Related Quality of Life?
• A multidimensional concept that captures
people’s perceptions about factors that are
important in their everyday lives
(Slade, 2002)
• Oral Health-Related Quality of Life (OHRQoL)
– Self-reports specifically pertaining to oral health
capturing both the functional ,social and psychological
impacts of oral disease
(Gift and Redford, 1992)

25. • No single instrument can be regarded as a
standard, comprehensive instrument for
measurement of OHRQoL.
• There will always be a need for both
generic and more diseases-/condition
specific instruments.

26. Other conditions

27. Oral cancer, distribution
• Life and death matter
• Age adjusted oral cancer mortality rate
among men has decreased.
• Female rates are low, but showed slight
further reduction
• Oral cancer: lip, tongue, buccal mucosa,
floor of mouth, salivary glands, and
pharynx.
• But not throat cancer.

28. • Squamus cell carcinoma of the tongue,
mucosa, lip: 80% of oral cancers
• Bet. 88~04: No. of new oral cancers
dropped
• Mortality also dropped, in absolute no anf
and in proportionate
• Oral caner is related to older age
• Mortality is related to low SES

29. • The standard measure for the severity is
the 5-y-survival rate: % of people still alive
after 5 y after diagnosis
• 5SR is decreased with increased
consumptions of the alcohol and social
deprivation
• Survival in higher if diagnosis made when
cancer is confined, nor spread

30. Oral cancer, risk factors
• %SR is 4 times when tumors diagnosed at
earlier stages, before metastasis.
• Tobacco use, heavy alcohol and poor diet
is responsible for 90% of all cancers.
• Risk for oral cancer from tobacco is equal
for men and women.
• Risk decrease after quitting
• Risk is more for pharyngeal cancer and
less for lip cancer

31. • Etio for submucus fibrosis: betel
• SMF and nodular luekoplakia has a hi
transformation rate
• Genetic role in oral caner is strong
• Other risk factors:
– Ill fitting dentures
– Long-term sun exposure
– Chronic inflammations: lichen planus
– leukoplakia

32. • Survival rate of oral cancer is low:
– Delay by patients seeking attention
– Delay in diagnosis by professionals
• Leukoplakia, erythroplakia are
precancerous
• Hi rate of second primary cancers in
patients of oral cancer

33. Other soft tissue lesions
• Precancerous lesion:
– Morphologically altered tissue in which cancer
is more likely to occur than its apparently
normal counterpart
• Leukoplakia:
– White patch that cannot be characterized
clinically or by pathological examination as
anything else

34. • Eruthroplakia:
– Bright red or velvety plaque that cannot be
characterized clinically or pathologically as
being due any thing else
• Papillary hyperplasia is related to ill fitting
dentures
• Little is known (distribution, prevelence,
risk factors) about the pemphigus,
pemphigoid, lichen planus, candidacies
and herpes infections.