Table 1.
Study characteristics and results reported from cross-sectional studies.
| Authors, year | Country | Location of data collection | Total number of respondents (Final sample size) | Subjects’ age (years) | Caries index | Socioeconomic indicator | Other measures | Association between socioeconomic indicators and dental caries | Newcastle-Ottawa scale |
|---|---|---|---|---|---|---|---|---|---|
| Nikias et al., 1975 [28] | USA | Clinical setting | 1,290 (1,122) | 19+ years | Decayed teeth | Status: poverty and non-poverty | Gender, age, edentulousness, soft tissue lesions, gingival status, oral hygiene levels, visit to dentist, frequency of brushing | Poverty and more dental caries | 5 (9) |
| Mean | (p < 0.05) * | ||||||||
| Number of decayed teeth: none, 1-2, 3 or more | |||||||||
| Hansen, 1977 [29] | Norway | Clinical setting | 177 (117) | 35 years | DMFT | Years of schooling | Gender | Less schooling and more dental caries | 6 (9) |
| Decayed teeth | (≤10 and >10) | ||||||||
| Mean | (p > 0.05) * | ||||||||
| Meyer et al., 1983 [30] | Portugal | Clinical setting | 73 (73) | 21 to 30 years | DMFT | Lower socioeconomic status (manual laborers) and higher socioeconomic status (the first three classes of students graduating from the new dental school in Lisbon) | Periodontal Index, gender, oral hygiene | Lower socioeconomic status and lower DMFT =15.9 ± 6.3, 10.0 ± 5.0 | 6 (9) |
| DMFS | |||||||||
| Mean | |||||||||
| DMFS = 42.6 ± 25.0, 24.1 ± 15.3 | |||||||||
| (p < 0.05) * | |||||||||
| Tervonen et al., 1991 [31] | Finland | Not reported | 1,600 (883) | 25, 35, 50 years | Number of decayed teeth | Years of education: university level, college, vocational school, compulsory, secondary school, less than 6 years of junior high school. | Periodontal disease, age, gender, number of teeth, regularity of attendance for treatment, attitude to preservation of teeth, and others. | Less schooling and more decayed teeth | 7 (9) |
| (p < 0.05) ** | |||||||||
| (D < 7 or ≥7) | |||||||||
| OR = 1.12 (1.03–1.20) | |||||||||
| Marcenes & Sheiham, 1992 [32] | Brazil | Subjects’ homes | 164 (164) | 35 to 44 years | DMFS | Socioeconomic status by ABA-ABIPEME | Periodontal status, age, frequency of brushing, sugar consumption, frequency of dental care, mental demand of work, marital quality, and others | Lower socioeconomic status and greater DMFS | 7 (9) |
| Mean | |||||||||
| (p < 0.05) * | |||||||||
| (p > 0.05) ** | |||||||||
| Eriksen et al., 1996 [33] | Portugal | Clinical setting | 322 (196) | 30 to 39 years | Number of decayed surfaces-DS | Social class: class 1, class 2 and class 3 | Smoking, psychological status, eating between meals, tooth cleaning (OHI-S), brushing frequency, interdental cleaning, use of fluoridated toothpaste, gender, regular dental visits, and others | Lower social class and more decayed surfaces | 6 (9) |
| Years of schooling: ≤10 and >10 | |||||||||
| (p > 0.05) * | |||||||||
| DS = 12.6 ± 11.1, 12.4 ± 11.6, 15.7 ± 13.2 | |||||||||
| Mean | |||||||||
| Less schooling and more decayed surfaces | |||||||||
| (p > 0.05) * | |||||||||
| DS = 14.5 ± 12.7, 11.7 ± 10.8 | |||||||||
| Berset et al., 1996 [34] | Norway | Dental Faculty, University of Oslo | 178 (121) | 35 years | DMFS | Social class: low, medium, high | Oral hygiene, brushing frequency, use of fluoride toothpaste, saliva secretion, mutans strep., gender, dental visits, and others | Low social class and carious surfaces | 7 (9) |
| Mean | |||||||||
| Years of schooling: ≤12 and >12 | |||||||||
| (p < 0.001)* | |||||||||
| (3.4 ± 4.1, 1.1 ± 1.1, 1.3 ± 1.5) | |||||||||
| Finances: no/minor/major problems | |||||||||
| <12 years of schooling and higher number of carious surfaces | |||||||||
| (p < 0.01) * | |||||||||
| (3.1 ± 3.8, 1.4 ± 1.8) | |||||||||
| Unsatisfied with own economic status and carious surfaces | |||||||||
| (p < 0.01) * | |||||||||
| (1.5 ± 2.0, 1.6 ± 1.3, 4.4 ± 4.5) | |||||||||
| Variation in decayed surfaces could be explained by social class, economic condition and others | |||||||||
| (R2 = 0.35) ** | |||||||||
| Hescot et al., 1997 [35] | France | Exam carried out on clusters (transport-able dental chair) | 1,000 (1,000) | 35 to 44 years | DMFT and decayed teeth (DT) | Occupational group: high, medium, low (derived from the combination of occupational activity, educational level and household income) | Gender, residence (urban, rural), one or more surface fillings, treatment need (pulp care, extraction or other treatment) | Lower occupational group and more decayed teeth | 6 (9) |
| Mean | |||||||||
| (p > 0.05) * | |||||||||
| DT = 0.9 ± 1.8, 1.2 ± 2.2, 1.3 ± 2.0 | |||||||||
| Schuller, 1999 [36] | Norway | Not reported | Evaluation of two sample groups in 1983 (945 (796)) and 1994 (702 (454)) | 23 to 24 years | Decayed and filled surfaces (DFS) | Years of education: ≤12 and ≥13 | Gender, residence (urban, rural), time since last dental visit, type of dental clinic, use of dental service, treatment received, oral hygiene score, and others | Less schooling and more decayed and filled surfaces in both years analyzed | 6 (9) |
| Mean | |||||||||
| (p < 0.05) * | |||||||||
| (1983 = 40.7, 37.0) | |||||||||
| (1994 = 22.3, 15.6) | |||||||||
| Sgan-Cohen et al., 1999 [37] | Israel | Clinical setting of military institute | 1,300 (1,084) | 25 to 44 years | DMFT | Years of education: <12, 12 and >12 | Gender, age | Less schooling and more decayed teeth | 6 (9) |
| Decayed teeth (DT) | |||||||||
| Mean | |||||||||
| (p < 0.001) * | |||||||||
| DT = 1.75 ± 2.4, 1.53 ± 2.2, 0,89 ± 1.4 | |||||||||
| (p < 0.001) ** | |||||||||
| Number of years of education with the D component-Rb = −0.16 | |||||||||
| Unell et al., 1999 [38] | Örebro and Östergötland(Sweden) | Not reported | 6,343 (513) | 50 years and older | Decayed and filled teeth | Occupational status: white-collar workers in leading positions, white-collar workers, entrepreneurs, blue-collar workers | Marital status, gender, residence (rural, town, city), working hours, general self-perceived health, mouth dryness, tobacco user, satisfied with dental care, use of dental services, and others | Lower occupational status and more decayed teeth | 7 (9) |
| Decayed teeth (DT) | |||||||||
| Education: college, high school/grammar school, | |||||||||
| (p < 0.05) ** | |||||||||
| secondary education, primary education | |||||||||
| Less schooling and more decayed teeth | |||||||||
| (p < 0.05) ** | |||||||||
| Brodeur et al., 2000 [40] | Canada | Not reported | 4,742 (2,110) | 35 to 44 years | DMFT/DMFS | Family income: | Last visit to a dentist, gender, number of teeth in mouth, language spoken, age, area of residence (metropolitan, urban, rural), and others | Lower income and more decayed | 7 (9) |
| Decayed surfaces (crown and root) DS | less than $30,000, $30,000 to $59,999, $60,000 and greater (ref.) | ||||||||
| Mean | (p < 0.05) * | ||||||||
| Number of decayed surfaces: ≤3 and ≥4 | Education: primary/high school, vocational training/college, university (ref.) | <$30,000-DS = 2.6 ≥$60,000-DS = 0.9 | |||||||
| (p < 0.05) ** | |||||||||
| OR = 3.8 (2.19–6.48) | |||||||||
| 2.9 (1.72–4.86) | |||||||||
| Less schooling and more decayed surfaces (p < 0.05) * | |||||||||
| Primary-DS = 2.3 | |||||||||
| University-DS = 1.3 | |||||||||
| (p > 0.05) ** | |||||||||
| OR = 1.2 (0.79–1.81) | |||||||||
| 1.1 (0.69–1.71) | |||||||||
| Doughan et al., 2000 [41] | Lebanon | Clinical setting | 401 (401) | 35 to 44 years | DMFT | Socioeconomic status: low, middle, high | Gender, residence (urban, rural), treatment need | Worse socioeconomic status and more decayed teeth | 7 (9) |
| Decayed teeth- DT | |||||||||
| Mean | |||||||||
| (p < 0.05) * | |||||||||
| DT = 5.7 ± 5.7, 4.0 ± 4.7, 2.2 ± 2.8) | |||||||||
| Skudutyte et al., 2000 [42] | Lithuania | Clinical setting | 767 (380) | 35 to 44 years | DMFT/DMFS | Education: low, medium, high | Gender, residence (urban, rural), fluoridated water, oral hygiene index (OHI-S) | Less schooling and more decayed teeth | 6 (9) |
| Decayed teeth-DT | |||||||||
| Decayed surfaces | |||||||||
| Mean/Median | |||||||||
| (p < 0.05) * | |||||||||
| DT = 3.0, 2.0, 1.0 | |||||||||
| Paulander et al., 2003 [45] | Sweden | Clinical setting | 588 (588) | 35 and 50 years | DMFS | Education: low and high | Number of teeth, probing attachment level, periodontal treatment needs, prevalence of dental caries, dietary habits, and others | Less schooling and more DS | 6 (9) |
| Decayed surfaces-DS | |||||||||
| Mean | |||||||||
| (p > 0.05) * | |||||||||
| 35 years- | |||||||||
| DS = 1.3 (−0.2–2.7) | |||||||||
| 0.5 (−0.3–1.1) | |||||||||
| 50 years- | |||||||||
| DS = 0.4 (0.2–0.6) | |||||||||
| 0.4 (0.1–0.7) | |||||||||
| Senna et al., 2005 [47] | Italy | Clinical setting of a military institute | 3,661 (2,908) | 19 to 25 years | DMFT | Educational level: completed college or graduate school, high school, secondary school and primary school | Gingival and periodontal status | Less schooling and more decayed teeth | 5 (9) |
| Decayed teeth-DT | |||||||||
| Mean | |||||||||
| (p < 0.05) * | |||||||||
| DT = 0.7 ± 1.2, 1.0 ± 1.4, 1.5 ± 1.9, 1.9 ± 1.9 | |||||||||
| Badel et al., 2006 [12] | Croatia | Clinical setting of a military institute | 248 (248) | 19 to 29 years | DMFT | Schooling in 3 categories: primary, secondary, university | Sugar intake | Less schooling and more decayed teeth | 6 (9) |
| Decayed teeth | |||||||||
| (quartile cutoffs: Q25, Q50 and Q75%) | |||||||||
| (p < 0.05) * | |||||||||
| Q75% = 5, 4, 1.5 | |||||||||
| Julihn et al., 2006 [48] | Sweden | Clinical setting | 800 (696) | 19 years | DMFS | Educational level of father: ≤9 years, 10–12 years, >12 years | Gender, chronic disease, country of birth, years living in Sweden, oral hygiene, attitude toward dental care, dental fear, gingival bleeding index (GBI), and others | Less education of the father and more decayed surfaces | 7 (9) |
| <10 and ≥10 | |||||||||
| Occupational status of mother and father: unemployed, laborer, white-collar worker | |||||||||
| (p < 0.01) * | |||||||||
| (p > 0.05) ** | |||||||||
| Worse occupation of the father and more decayed surfaces | |||||||||
| (p < 0.01) * | |||||||||
| (p > 0.05) ** | |||||||||
| Worse occupation of the mother and more decayed surfaces | |||||||||
| (p < 0.01) * | |||||||||
| (p > 0.05) ** | |||||||||
| Varenne et al., 2006 [49] | Burkina Faso | Subjects’ homes | 493 (493) | 35 to 44 years | DMFT | Occupation: shop keeper, government employee, smallholder/craftsman, housewife, farmer/breeder(ref.) | Gender, ethnical group, dental visits, use of chewstick, consumption of fresh fruits, location (urban, rural), and others | Government employee and higher DMFT | 7 (9) |
| Mean | |||||||||
| Absence/presence of caries | |||||||||
| Educational level: high, moderate, low | |||||||||
| (p < 0.05) ** | |||||||||
| OR = 5.26 | |||||||||
| High educational level and higher CPOD | |||||||||
| (p < 0.05) ** | |||||||||
| OR = 2.99 | |||||||||
| Hessari et al., 2007 [51] | Iran | Non-specific | 8,301 (8,301) | 35 to 44 years | DMFT | Level of education: illiterate, low, medium, high | Gender, place of residence (urban, rural) | Less schooling and more decayed teeth | 7 (9) |
| Decayed teeth-DT | |||||||||
| Mean | |||||||||
| (p < 0.05) * | |||||||||
| Men-DT = 2.7 ± 2.7, 2.8 ± 2.6, 2.4 ± 2.7, 1.9 ± 2.4 | |||||||||
| Women-DT = 2.8 ± 2.7, 2.8 ± 2.8, 1.9 ± 2.4, 1.9 ± 2.6 | |||||||||
| Roberts-Thomson & Stewart, 2008 [52] | Australia | Clinical setting | 1,261(644) | 20 to 24 years | DMFS | Tertiary education (yes or no) | Gender, country of birth, living at home, visit in last 2 years, usual reason for visit, site of last visit, brushing, current smoker, alcohol use, and others | Less schooling and more cavitated caries (p > 0.05) * | 7 (9) |
| Decayed surfaces-DS | Employed (yes or no) | ||||||||
| Mean | Income (<$20,000 or $20,000 or more) | ||||||||
| DMFS modified by Protocol of US National Institute of Dental Research: precavitated decayed surface | |||||||||
| Government benefits (yes or no) | |||||||||
| DS = 0.64 ± 3.00, 1.06 ± 2.55 | |||||||||
| Unemployed and more cavitated caries (p < 0.05) * | |||||||||
| Mean | |||||||||
| DS = 0.64 ± 1.47, 1.16 ± 5.83 | |||||||||
| (p < 0.05) ** | |||||||||
| Lower income and more cavitated caries (p > 0.05) * | |||||||||
| DS = 0.94 ± 3.18, 0.85 ± 2.18 | |||||||||
| Receiving benefits and more cavitated caries (p < 0.05) * | |||||||||
| DS = 1.68 ± 4.94, 0.70 ± 1.76 | |||||||||
| (p > 0.05) ** | |||||||||
| Skudutyte-Rysstad et al., 2009 [54] | Norway | Clinical setting | 149 (149) | 35 years | DMFT | Education: no university or university | Gender, marital status, region of birth, dental anxiety score, frequency of brushing, use of dental floss, dental visits, time since last dental visit, smoking | Less schooling and more decayed surfaces | 6 (9) |
| DMFS | Household income (NOK/year): | ||||||||
| Decayed surfaces on dentin (≥2 and <2)-DS | ≤299,000 (low), | ||||||||
| 300,000–599,000 (medium) and ≥600,000 (high) | |||||||||
| (p < 0.05) * | |||||||||
| Lower income and more decayed surfaces | |||||||||
| (p < 0.05) * | |||||||||
| (p < 0.05) ** | |||||||||
| DS-OR = 4.5 (1.9–10.2) | |||||||||
| Brennan et al., 2010 [17] | Australia | Clinical setting | 879 (709) | 45 to 54 years | DMFT | Household income: under AU$30,000, AU$30,000–$60,000, over AU$60,000 | Gender, place of birth, dental knowledge of tooth decay prevention | Lower income and more decayed teeth | 7 (9) |
| Decayed teeth-DT | |||||||||
| Mean | |||||||||
| (p < 0.01) * | |||||||||
| DT = 0.8 ± 0.13, 0.4 ± 0.07, 0.2 ± 0.03 | |||||||||
| (p < 0.01) ** | |||||||||
| Geyer et al., 2010 [16] | Germany | Not reported | 1,779 (925) | 35 to 44 years | DMFT | Income in categories: highest, second highest, intermediate, second lowest and lowest; | Gender, age (years) | Lower income and higher DMFT | 7 (9) |
| (≤21 and >21) | |||||||||
| Educational level: 12–13 years, 10 years and 8–9 years of schooling | (p < 0.05) * | ||||||||
| OR = 3.74 (1.66–8.46) | |||||||||
| Cumulative effects: income + educational level l = highest socioeconomic positions, intermediate positions, lowest positions | |||||||||
| (p < 0.05) ** | |||||||||
| OR= 2.34 (1.00–5.55) | |||||||||
| Less schooling and higher DMFT | |||||||||
| (p < 0.05) * | |||||||||
| OR = 3.75 (1.99–7.05) | |||||||||
| (p < 0.05) ** | |||||||||
| OR = 2.95 (1.52–5.74) | |||||||||
| Socioeconomic status - lowest positions: income + education level and higher DMFT | |||||||||
| (p < 0.05)** | |||||||||
| OR = 6.06 (2.06–17.87) | |||||||||
| Celeste et al., 2011 [55] | Brazil | Subjects’ homes | 22,839 (20,695) | 35 to 44 years | DMFT | Gini (quartile), municipal income (quartile), household income (based on minimum wage) | Gender, age, place of residence (urban, rural), last dental visit., edentulism, prevalence of periodontal attachment loss >8 mm | More iniquity results in more decayed teeth | 7 (9) |
| Untreated dental caries | |||||||||
| Mean | |||||||||
| (p < 0.05) ** | |||||||||
| Brennan et al., 2011 [18] | Australia | Clinical setting | 879 (709) | 45 to 54 years | DMFT | Household income (under $80,000+ and <$80,000 | Dental visit pattern, dental self-care (tooth brushing) | Lower income and more decayed teeth | 7 (9) |
| Decayed teeth-DT | |||||||||
| Mean | Education: tertiary and secondary | ||||||||
| (p < 0.01) * | |||||||||
| DT = 0.1 ± 0.03, 0.5 ± 0.05 | |||||||||
| (p < 0.001) ** | |||||||||
| Income $80,000+ | |||||||||
| Beta = −0.27 | |||||||||
| Lesser schooling and more decayed teeth | |||||||||
| (p < 0.01) * | |||||||||
| DT = 0.2 ± 0.03, 0.5 ± 0.06 | |||||||||
| (p < 0.01) ** | |||||||||
| Education tertiary Beta = −0.25 | |||||||||
| Chandra et al., 2011 [56] | India | Not reported | 1,198 (1,187) | 19 to 57 years | DMFT | Socioeconomic status(SES): upper, upper middle, lower middle, upper lower, lower | Gender, periodontal status, oral pre-malignant, malignant lesions, demographic profile, etc. | Lower socioeconomic status and more decayed teeth | 6 (9) |
| Decayed teeth-DT | |||||||||
| Mean | |||||||||
| (Modified Kuppuswamy scale were based on the 1988–1989) | |||||||||
| (p < 0.001)* | |||||||||
| Upper-DT = 0.07 (±0.32) | |||||||||
| Lower DT = 0.96 (±2.06) |
* Bivariate analysis; ** multivariate analysis.