Title: The Epidemiology of Dental Caries
1The Epidemiology of Dental Caries
Department of Preventive Dentistry School
Hospital of Stomatology Wuhan
University Minquan Du ???
2Types of study
- Descriptive studies cross-sectional,
longitudinal, historical - Analytical studies case-control, cohort
- Experimental study Clinical trials,
Intervention, fields trials
3?????? ??
- An Index is a graduated, numerical scale with
upper and lower limits, with scores in the scale
corresponding to specific criteria - ???????????????????
- ????????
- ????????,??????????????????
4An Ideal Index
- ?? Simplicity
- ?? Acceptability
- ?? Validity
- ?? Reliability
- ?? Sensitivity
- ??????? Quantifiability
5- ????? reversible
- ???? gingivitis
- ????? cumulative
- DMF, dental caries
6Scale for measurement
- Nominal scaleOrthodontic angles classification
- Marital status single, married, divorced,
windowed - Colour of hair red, yellow, black, green
- Types of Blood O, A, B , AB
- Ordinal scale plaque index Gingival Index, CPI
- Years of education 0, 1-5, 6-9, gt10
- Severity of disease mild, moderate,
severity - Interval temperature in Celsius temperature 22
and 26, 32 and 36 - Ratio weight, mortality rate, DMFT
7Examine equipment
- Artificial light
- Dental mirror
- CPI probe
8A specially designed light weight CPI probe with
a 0.5-mm ball tip is used, with a black band
between 3.5 and 5.5 mm and between 8.5 and 11.5
mm from the ball tip
9Oral Health Surveys 4th Edition
- Code
Conditions - Primary teeth Permanent teeth
- Crown Crown Root
- A 0 0
Sound - B 1 1
Decayed - C 2 2
Filled, with decay - D 3 3
Filled, no decay - E 4 -
Missing
10(No Transcript)
11(No Transcript)
12????????
- ???????
- DMF?????????????????
D(decayed)M(missing)F(filled)T(teeth)
D(decayed)M(missing)F(filled) S(surface)
13 ??????? dmft,dmfs?????????????????
deft,defs ?????????????????
dft,dfs ???????????????
14deciduous caries
15??????
- Mean DMFT?????????????????????
- ????????
- ??
- ????
Mean DMFS??????????????????????
????????? ???
????
16? ?
17 ???(caries prevalence rate)
?????????????????,?????????
???
100
????
18?????(caries incidence rate)
??????????,???????????
?????
100
????
19- 1995????????15???50?, ???????35?,??????D70,
M2, F8,???????D210, M10, F16? - ??????50?????,????10????????,???????15,????
18,????????1995????????????????????????
20???(caries-free rate)
??????????????????????
???
100
???????
21??????? (proportion)
- ???????????????????????????
- ??????????
- ??????? 100
- ??????????????
22????(Katz, root caries index)
????????,??????????????????????????
????
100
???????
23????(Katz, root caries index)
An individual, or population
- Root surfaces decayed filled
RCI
100
Root surfaces with loss of periodontal
attachment Decayed Filled Sound
24(No Transcript)
25??? 3544????????
?? ?? Â ?? ?? ????????? ?????(SD) ???????????(SD) RCI()
? 270 174 0.15 (0.55) 5.12 (6.41) 4.57 (15.74)
?? ? 270 172 0.19 (0.54) 4.35 (5.69) 8.29 (21.82)
? 540 346 0.17(0.55) 4.74 (6.07) 6.42 (19.07)
? 270 216 0.26(0.84) 6.97(6.62) 4.60(14.64)
?? ? 270 198 0.23(0.61) 4.64(5.49) 7.91(21.13)
? 540 414 0.24(0.74) 5.81(6.19) 6.18(18.09)
? 540 390 0.21(0.72) 6.05(6.58) 4.59(15.11)
?? ? 540 370 0.21(0.58) 4.50(5.59) 8.08(21.42)
? 1080 760 0.21(0.65) 5.27(6.15) 6.29(18.53)
26- Root Caries Index according to teeth type
- in 3544 years old adults
27???6574????????
?? ?? Â n ????????? ?????(SD) ???????????(SD) RCI()
? 270 258 0.71 (1.28) 11.79 (6.81) 8.38 (17.09)
?? ? 270 255 1.10 (1.62) 10.46 (6.43) 13.05(21.79)
? 540 513 0.90 (1.47) 11.13 (6.65) 10.70 (19.68)
? 270 250 1.00 (1.68) 10.75(6.74) 12.19 (20.47)
?? ? 270 248 1.19 (1.80) 9.71 (6.35) 14.30 (20.80)
? 540 498 1.10 (1.74) 10.23 (6.56) 13.24 (20.64)
? 540 508 0.86(1.50) 11.27 (6.79) 10.26 (18.90)
?? ? 540 503 1.14(1.71) 10.08 (6.40) 13.67 (21.29)
? 1080 1011 1.00 (1.62) 10.68 (6.62) 11.95 (20.19)
28- Root Caries Index according to teeth type
- in 6574 years old adults
29Community Dent Oral Epidemiol 2009 37
26026 Root caries patterns and risk factors of
middle-aged and elderly people in China Du MQ,
Jiang H, Tai BJ, Zhou Y, Wu B, Bian Z.
Abstract The objectives of this study were to
describe root caries patterns of Chinese adults
and to analyze the effect of selected demographic
and socioeconomic factors on these patterns. A
total sample of 1080 residents aged 3544-years-ol
d and 1080 residents aged 6574-years-old from
three urban and
30???????????????The epidemic characteristics of
dental caries and its risk factors
31WHO???????????(12?)
- ?? (DMFT) ??
- 0.01.1 ??
- 1.22.6 ?
- 2.74.4 ?
- 4.56.5 ?
- 6.6?? ??
32Distribution of Region ????
- ???????????????,????????????
- ??????,????????????????,????????????
- ??????????????????????????????
33????????????10???12?????
- ?? ???? ?? ??
???? ?? - ?? 1991 1.4
???? 1987 6.4 - ?? 1993 1.4
???? 1987 8.1 - ?? 1998 1.9
? ? 1990 7.0 - ?? 1992 2.6
? ? 1995 6.7 - ?? 1993 3.3
? ? 1986 6.7 - ??? 1995 2.2
???? 1988 6.3 - ??? 1993 2.3 ? ?
? 1989 6.0 - ??? 1989 1.9 ? ?
? 1983 5.9 - ???? 1993 1.1 ????
1988 5.9 - ?? 1994 1.2
???? 1993 5.7
34????
35?????????(2005)
?? 5? 12? 3544? 6574? ??
?? ?? ?? ?? 3.7 68.4 0.6
32.5 2.1 63.8 3.6 75.0 ?? 3.2 63.0 0.5
25.3 1.9 60.7 3.7 75.6
36(No Transcript)
37Distribution of Time ????
- ??11??12???????(??)
??
??(1983) ??(1995)
- ??? 1.41
0.98 - ??? 1.17
0.96 - ??? 1.41
1.02 - ??? 0.36
0.87 - ??? 0.69
0.59 - ??? 0.46
0.88 - ??? 0.76
1.29 - ??? 1.22
1.46 - ??? 0.90
0.51 - ??? 0.91
1.65 - ??? 0.57
0.37 - ? ?
0.67 0.88
38Prevalence of deciduous caries in 5-year-old
children in Hubei province
year dmft
Prevalence () 1995 3.6
70.2 2005
2.5 55.5
39Dental caries of permanent teeth
DMFT
Prevalence() 1995
2005 1995 2005 5
3.6 2.4
70.2 55.5 12 0.7
0.4 34.1 22.7
15 1.0 0.5
41.8 24.4 3544 1.4
1.2 53.0 47.0
6574 3.0 3.7
74.4 77.2
40Comparison of Prevalence of Root caries in adults
41Distribution of population ????
- Age ??
- Gender ??
- Urban and rural areas ??
- Race and Ethnicity ??
42Age
- ????????????,?????????
- ?3??????????,?58??????????
- 6?????????,??????,???????
- 1215???????????,????????
- 25???????????
- ?????,??????,???????????
43 ??11??544????????????(1995) ??
?? D M F
DMF
5? ?
0.54 0.00 0.00
0.54 ? 0.95
0.02 0.00 0.96
12? ? 37.74 0.36
6.00 40.60
? 47.37 0.47 8.22
51.02 15? ? 42.86
1.30 10.61 47.74
? 51.74 1.58
14.10 57.11 18? ?
44.25 2.52 15.01
50.52 ? 52.06
3.72 20.02 60.11 3544?
? 40.93 24.07 16.31
56.45 ?
54.43 28.98 25.04 69.56
44Dental caries of permanent teeth
DMFT
Prevalence() 1995
2005 1995 2005 5
3.6 2.4
70.2 55.5 12 0.7
0.4 34.1 22.7
15 1.0 0.5
41.8 24.4 3544 1.4
1.2 53.0 47.0
6574 3.0 3.7
74.4 77.2
45Gender
- ??????????,?????????
- ????????????
- ????????????
- ????????????????,??????????????????,????????
????????????????????????
46 ???? (2005)
- ??? ?? ??
- ?? ??? ?? ???
- 5?? 3.5 66.3 3.5 65.7
- 12?? 0.5 25.3 0.6 32.5
- 3544?? 1.1 44.7 1.9 61.3
- 6574?? 2.9 68.6 3.6 75.0
47???3544?????????? (2005)
?? ?? ???? D ?? SD F ?? SD DFT ?? SD ???()
?? ? 270 0.71 1.42 0.14 0.46 0.86 1.51 38.9
? 270 0.86 1.39 0.39 1.06 1.25 1.81 49.3
?? 540 0.79 1.41 0.26 0.83 1.05 1.67 44.1
?? ? 270 0.80 1.55 0.01 0.11 0.81 1.56 38.1
? 270 1.66 2.28 0.11 0.49 1.77 2.40 61.9
?? 540 1.23 2.00 0.06 0.36 1.29 2.08 50.0
?? ? 540 0.76 1.49 0.08 0.34 0.84 1.53 38.5
? 540 1.25 1.93 0.25 0.84 1.51 2.14 55.6
?? 1080 1.01 1.74 0.16 0.65 1.17 1.89 47.0
48???6574??????????(2005)
?? ?? ???? D ?? SD F ?? SD DFT ?? SD ???()
?? ? 270 2.55 3.24 0.16 0.55 2.71 3.26 69.3
? 270 3.41 3.85 0.34 0.94 3.75 3.85 80.0
?? 540 2.98 3.58 0.25 0.78 3.23 3.60 74.6
?? ? 270 3.81 4.19 0.02 0.14 3.83 4.19 77.0
? 270 4.36 4.08 0.03 0.20 4.39 4.06 82.6
?? 540 4.08 4.14 0.03 0.17 4.11 4.13 79.8
?? ? 540 3.18 3.80 0.09 0.41 3.27 3.79 73.1
? 540 3.88 3.99 0.19 0.70 4.07 3.97 81.3
?? 1080 3.53 3.91 0.14 0.57 3.67 3.90 77.2
49Urban and rural areas
- ??????,??????????????
- ?????????????(??????)?????????????,???????????????
?????
50 ??11??544??????????(1995) ??(?)
??() ??() 5
0.65
0.94 12 48.32
40.82 15
55.70 45.89
18 58.22
49.53 3544
64.55 59.92
51- ???????????????(2005)
- ??? ?? ??
- ?? ??? ?? ???
- 5?? 3.09 62.0 3.92 70.2
- 12?? 0.53 29.3 0.54 28.6
- 3544?? 1.87 61.4 1.96 60.7
- 6574?? 3.30 74.8 3.95 75.5
- 95????5????????????????
52Race and Ethnicity
- ??????,?????????????,?????????????????
????
53?????????
- The amount of fluoride intake
- The diet an nutrition
- The transmittion of cariogenic bactrias
54Fluoride intake
- ???????????,??????????????
- ???????0.60.8ppm???
55(No Transcript)
56??????????11?????????????????1995
57Diet and nutrition
- ??????????????????????????,?????,?????
?? - ???????????????
58????
59????
60Familial tendency
- ??????????,???????????????????????????????,???????
??????? - ?????????,??????????????????,????????????????
61(No Transcript)
62Randomized controlled trial,RCT
- ????????????????,?????????,???????????????,???????
,??????????????????????????????? - ???????,?????,?????????,???????????????,??????????
???????
63What is a clinical trial?
- ClinicalTrials.gov includes both
interventional and observational types of
studies. - --Interventional studies are those in which the
research subjects are assigned by the
investigator to a treatment or other
intervention, and their outcomes are measured. - --Observational studies are those in which
individuals are observed and their outcomes are
measured by the investigators.
64- Clinical trials provide the best scientific
evidence for clinicians when they have to make
clinical decisions (Evidence-based dentistry) - We would like to produce the highest level of
evidence to guide the best practice
65What is a protocol?
- A protocol is a study plan on which all clinical
trials are based. The plan is carefully designed
to safeguard the health of the participants as
well as answer specific research questions. - A protocol describes what types of people may
participate in the trial the schedule of tests,
procedures, medications, and dosages and the
length of the study. While in a clinical trial,
participants following a protocol are seen
regularly by the research staff to monitor their
health and to determine the safety and
effectiveness of their treatment.
66Clinical study protocol
- ? A written protocol
- ? Controlled trials
- ? Randomisation
- ? Size of trial
- ? Double blind trials
- ? Definition of patients
67Clinical study protocol
- ? Data management
- ? Statistical analysis
- ? Monitoring of trials
- ? Ethical consideration
- ? Adverse effect
- ? Staff, funding
- ? Publications
68Randomized controlled trial
- ? Randomization Random numbers, throw a coin,
dice. - ? Control Study group, Positive control,
Negative control - ? Blind Single blind, Double blind, or placebo
- ? Replication
-
69Randomization
- ?????(Simple randomization)??????????????????????
????????????????????????,?????????,?????????? - ?????(Block randomization)???????????????????????
????????????,????????????????,????????????????,???
??????????????????46???? - ?????(Stratified randomization)??????????????????
???,????????????,??????????????????????????,??????
????????????????
70Randomisation
- The objective of randomisation is to ensure
that there is no bias which will make the results
invalid - Randomized controlled trial (RCT)
-
- Random numbers, throw a coin, dice.
71(No Transcript)
72Random numbers
- Table
Random numbers - --------------------------------------------------
---------------------------------------------- - Rows
Columns -
1-4 5-8 9-12
1
96
22 74 70 80 46
2
82 14 73 36
41 54 3
21 47
59 93 48 40
4
89 31 62 79 45 73
5
63 29 90 61
86 39 6
71 68 93 94 08 72
7
05 06 96 63
58 24 8
06 32
57 11 81 59
9
91 15 38 54 73 30
10
54 60 28 35
32 94 - --------------------------------------------------
------------------------------------------------
73Control
- ????(??????)??????????????,?????????????????????,
?????????????????? - ????(concurrent control)??????????????,??????????
?????????,?????????????????,????????????? - ????(self control)????????????????????,?????,????
?,???????????????????????????????????????,????????
???????? - ?????(placebo control) ????????,?????????????????
????????,?????????????????????????????????,???????
??,???????? - ????(blank control)?????????????????????????????
??,????????????????,????????????????????
74Control
- Study group - subjects receiving the test
intervention - Control group - subjects as similar as possible
to study group but not receiving test
intervention - Positive control, Negative control, Historical
control, Self control
75What is a control or control group?
- A control is the standard by which experimental
observations are evaluated. In many clinical
trials, one group of patients will be given an
experimental drug or treatment, while the control
group is given either a standard treatment for
the illness or a placebo.
76What is a placebo?
- A placebo is an inactive pill, liquid, or powder
that has no treatment value. In clinical trials,
experimental treatments are often compared with
placebos to assess the experimental treatment's
effectiveness. In some studies, the participants
in the control group will receive a placebo
instead of an active drug or experimental
treatment.
77Blind
- ?????????,?????,?????????????????????????????????
???????????????????????? - ?????????????????????????????????????????????,???
???? - ?????????????????????????????????????????????????
??????,????????????,?????
78Blind
- Blind - examiners do not know which subjects are
in the test or control group to avoid
(unintentional) bias of examiner reporting - Double blind - participants not knowing which
group they belong to to avoid subjective bias in
reporting of symptoms - Dummy or placebo - similar to test intervention
in all respects but is missing active ingredient
under investigation
79Sample size estimation
- ??????(sample size estimation)???????????????????
- ?????????,?????,??????????,??????????????????????
??????????????????????,????????? - ??????????????????????????????,???????????????????
????????????????????100?,????????,???????????30??
80Sample size
- ?Samples which are too small can prove nothing,
samples which are too large can prove anything
How big should my sample be ? has been likened
to the question How much money should I take
when I go on vacation? ( How long a vacant?
Doing what? Where? Which whom? ) - ? Calculations of sample size require both
decisions and surmises.
81Optimal sample size
- Two-sided significance levela 0.05
- Power of the test, 1- ß 80, 90
- Clinically relevant difference d
- The standard deviation of the difference s
- N1N216 (s /d)2 a0.05, 1-ß80
- N1N221 (s /d)2 a0.05, 1-ß90
82????
- ???? ??????????????????????????????????????????
??????????,????????????? - ???? ??????????????????????????????????????????
??????????????????? - ???? ???????????????,?????????????????
83????
- ???????????????(measurement variable)?????????????
???????????,??????????????????????????? - ??????????(categorical variable)??????????????????
?????????????????????????????????????????????????
??????????????????,??????????????,???????????
84Scale for measurement
- Nominal scaleOrthodontic angles classification
- Marital status single, married, divorced,
windowed - Colour of hair red, yellow, black, green
- Types of Blood O, A, B , AB
- Ordinal scale plaque index Gingival Index, CPI
- Years of education 0, 1-5, 6-9, gt10
- Severity of disease mild, moderate,
severity - Interval temperature in Celsius temperature 22
and 26, 32 and 36 - Ratio weight, mortality rate, DMFT
85What are the different types of clinical trials?
- Treatment trials test experimental
treatments, new combinations of drugs, or new
approaches to surgery or radiation
therapy.Prevention trials look for better ways
to prevent disease in people who have never had
the disease or to prevent a disease from
returning. These approaches may include
medicines, vaccines, vitamins, minerals, or
lifestyle changes.Diagnostic trials are
conducted to find better tests or procedures for
diagnosing a particular disease or
condition.Screening trials test the best way to
detect certain diseases or health
conditions.Quality of Life trials (or
Supportive Care trials) explore ways to improve
comfort and the quality of life for individuals
with a chronic illness.
86Study designs for clinical trials
- Historical comparison
- Parallel groups
- Factorial
- Cross-over
- Split mouth design
-
87Ethical issues
- ? never conduct a study without a practical
objective in view which will be of benefit to the
community - ? never conduct a study to assess treatment needs
without discussing the criteria involved with
those clinicians expected to carry out the
identified treatment
88Ethical Considerations
- ICH GCP requirements for the composition of the
Ethics Committee (IRB) - At least 5 members
- At least 1 member whose primary interest is
non-scientific (lay member) - At least 1 member who is independent of the trial
site - Only members who are independent of the
investigator can vote or provide an opinion
89What is informed consent?
- Informed consent is the process of learning the
key facts about a clinical trial before deciding
whether or not to participate. It is also a
continuing process throughout the study to
provide information for participants. To help
someone decide whether or not to participate, the
doctors and nurses involved in the trial explain
the details of the study. - Then the research team provides an informed
consent document that includes details about the
study, such as its purpose, duration, required
procedures, and key contacts. Risks and potential
benefits are explained in the informed consent
document. - The participant then decides whether or not to
sign the document. Informed consent is not a
contract, and the participant may withdraw from
the trial at any time.
90What are side effects and adverse reactions?
- Side effects are any undesired actions or effects
of the experimental drug or treatment. Negative
or adverse effects may include headache, nausea,
hair loss, skin irritation, or other physical
problems. Experimental treatments must be
evaluated for both immediate and long-term side
effects.
91??????
- ???? ??????????????,?????????????????????????????
?????????1?1.23??????????????? - ???? ??????????????????????????
- ???? 34?????????,
- ????????? ?????,???????????????????????WHO???????
,?2???????????2?????????????????
H Jiang, Z Bian, BJ Tai, et al. The effect of a
Bi-annual professional application of APF foam on
dental caries increment in primary teeth
24-month clinical trial. J Dent Res,
200584(3)265-8.
92???????????
- ???? NovaMin ?????????????????,????????????,?????
?????????????????6??????,??NovaMin????????????????
????????????? - ???? ????????????????????????
- ????????? ??????(Silness Löe Plaque Index ,
PLI) ???????(Gingival Bleeding Index,
GBI)?????????????? -
Baojun Tai, Zhuan Bian, Han Jiang, et al.
Anti-gingivitis effect of a dentifrice containing
bioactive glass (NovaMin) particulate J Clin
Periodontol, 2006 3386-91.
93??????????
- ????????NovaMin??????????????????????????????????
????6??????NovaMin????????????????????? - ???? ?????????????????????
- ???? Visual Analog Scale,VAS
Du MQ, Bian Z , Jiang H, et al. A
Clinical Evaluation of a Dentifrice Containing
Calcium Sodium Phosphosilicate (NovaMin) for the
Treatment of Dentinal Hypersensitivity. Jouranl
of Amercian Dental Assocaition, 2009
94?????????
- ???? ?????????????????????????3?????(10?15?20)
?????????????,??????????,??????????????????????? - ???? ???????????????????????
- ????????? ??Vitalescence Esthetic Restorative
Masters Shade Guilde (Ultradent
??)???????,???????????????????,???????????,??????3
??????,???????????????L?a?b??
Matis BA, Wang YN, Jiang T, et al. Extend
at-home bleachin of tetracycline-stained teeth
with different concetrations of carbamide
peroxide. Quintessence International, 2002,
33(9)645-655.
95?????????
- ???????????????????????????????????????????,?????
?????????????????3?????????? - ???? ???????????????????????????
- ????????? ?????????????????,????????????????????
??1??,??3??????(???1.5???4.0????12.0??)4??????????
???????????????????????????,??2????????,??????????
?10?????????
96????????
- ?????????????????????????,???????????????????????
???????????????,??????????????? - ???????????????????????????
- ???? ???????,???????,????????????????????????,??
?2??????? - ????????? ??????????X??,??????,?????????????
??, ???, ??,?. ??????????????????. ????????,2005,
38(3)192-195.
97???????????
- ???????????????????????????????????????
- ??????Etoricoxib??????????????????????????????
- Etoricoxib??????????(COX)-2??????,????????????????
??????????????60mg?120mg?180mg?240mg?????Etoricoxi
b????????????????????
98New Law Requiring Registration at Clinical
Trials.gov
- On September 27, 2007, a US law was enacted that
expands the types of clinical trials that must be
registered in ClinicalTrials.gov, increases the
number of data elements that must be submitted,
and also requires submission of study results.
99(No Transcript)