Smoking leads to loss of teeth

A RT I C L E A N A LY S I S & E VA LUAT I O N Smoking leads to loss of teeth Original Article:

Chen X, Wolff L, Aeppli D, Guo Z, Luan W-M, Baelum V, et al. Cigarette smoking, salivary/gingival crevicular fluid cotinine and periodontal status. A 10-year longitudinal study. J Clin Periodontol 2001;28:331-9.

• Level of Evidence: • Purpose:

2 To determine association between salivary/gingival crevicular fluid cotinine and periodontal status

• Source of Funding: • Type of Study/Design:

Not available Cohort

S UMMARY SUBJECTS The subjects were 147 smokers and 30 nonsmokers. A total of 58 smokers (40%) contributed cotinine values. The study was carried out in the rural Beijing area of China in 1984 and 1994.

MAIN RESULTS

EXPOSURE The exposure was smoking. MAIN OUTCOME MEASURE A 10-year loss of teeth was the main outcome measure.

A 10-year tooth loss was significantly greater in smokers than nonsmokers. The mean difference was 1.5 (P < .001; Table 3).

Table 3. Mean number of teeth (T) present in 1984 and in 1994 and mean tooth loss in nonsmokers and smokers Nonsmokers (n = 30) Age in 1994 (years) ≤ 39 40 ≤ 49 50 ≤ 59 > 59 Over-all weighted mean and SE#

T present

Smokers (n =147)

Tooth loss

1984

1994

Mean

27.8 26.8 25.4 22.6 25.8

26.3 25.6 21.4 19.0 23.3

1.5 1.2 4.0 3.7 2.5

SD

T present

Median

1.7 2.5 5.7 4.4 0.08 (SE)

1 0 1 2

Tooth loss

n†

1984

1994

Mean

4 10 7 9

27.6 26.8 25.8 21.7 25.6

26.7 23.8 22.1 12.1 21.6

0.9 3.0 3.7 9.6 4.0

SD Median n† 1.8 0 5.0 1 5.0 2 7.6 8 0.05 (SE)

45 36 36 30

P < .001 SD, Standard deviation. †n, Number of subjects. # Weights used were proportion of all subjects in each age group (49/177, 46/177, 43/177, 39/177), SE is the corresponding standard error. Mean tooth loss in smokers compared to nonsmokers was statistically significant based on a stratified analysis with weights being inverse to the variance. (Reprinted from Chen et al. J Clin Periodontol 2001;28:331-9. By permission.)

J Evid Base Dent Pract 2002;2:48-49

©

2002 Mosby, Inc. All rights reserved. doi:10.1067/med.2002.122657

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C OMMENT ARY

CONCLUSIONS Smoking is associated with a deterioration of periodontal condition in terms of lost teeth.

ANALYSIS According to the authors the purpose of the study was to determine the relationship between salivary/gingival crevicular fluid cotinine and periodontal status. Unfortunately, salivary/ gingival crevicular fluid cotinine data were available for fewer than 40% of the study sample. Clinical data were reported for 147 smokers and 30 controls. It is not demonstrated whether or not clinical data of cotinine-tested smokers were representative of all smokers. Therefore, the results of the study with regard to cotinine asso-

• Contents Reviewer:

Journal of Evidence-Based Dental Practice Volume 2, Number 1

ciation with periodontal status are not reliable. Another flaw is the omission to take into account the number of lost teeth when calculating 10-year changes in probing depth. This will most probably result in an underestimation of the number of sites that worsened over time. This effect will affect smoker values comparably more, as smokers lost significantly more teeth, and so may conceal real differences in probing-depth worsening. Therefore, some of the results on the periodontal status are not reliable. The most valid outcome of the study, although this was not stated as an aim, seems to be observations confirming earlier studies that smoking is associated with loss of teeth.

Jan Bergstrom, Karolinski Institute, Huddinge, Sweden

Chen et al 49