Assessing socioeconomic status through dental and associated tissue characteristics: A cross-sectional study for human identification

Introduction

The impact of socioeconomic status (SES) on oral health is indeed significant. People with low SES tend to have higher rates of dental issues, often due to limited access to essential resources such as healthcare and proper nutrition. In India, research has shown that SES influences oral health indirectly, with poor SES negatively affecting oral health outcomes.¹ Socioeconomic status plays a vital role in mediating the relationship between dental maturation and access to crucial resources necessary for healthy growth and development. Comparing patients from different socioeconomic backgrounds can provide insights into disparities in access to resources such as nutrition and healthcare.² Assessing a patient’s SES through their teeth, dental treatments, and oral hygiene, as well as demographic information, occupation, and education level can offer valuable information. The idea of the project is to reverse engineer the prediction of SES on the basis of dental and associated findings. The data used for human identification is surrogately classified based on SES such as school admissions, ration cards, car rentals, travel itineraries etc. The estimation of SESs can prove to be an efficient tool to narrow down the relevant data set from which human identification is possible. Hence, this study aims to explore the connection between SES and tooth structure, shedding light on how these factors are intertwined in influencing oral health.³ This study aims to assess the correlation between dental health status and SES among individuals, with a focus on identifying predictors of SES based on dental health indicators

Methods

A cross-sectional study was conducted to evaluate the correlation between dental health status and socioeconomic status among individuals. The sample of the study was composed of a total of 135 subjects who had visited the Department of Oral Medicine and Radiology for various forms of dental care. The participants were initially briefed about the study. Once the subject was willing to participate in the study, the principal investigator entered the details in the information sheet. The study was conducted after the approval of the Institutional Ethics Committee (Protocol no. 24105,13/8/2024). The study included adults aged 18-65 years. Participants were recruited using convenience sampling from various urban and rural locations.

Results

A total of 135 participants aged 18 and above were included in the study. Of these, 73 (54.1%) were female and 62 (45.9%) were male. Additionally, 96 (71.1%) were married and 39 (28.9%) were single. 123 (91.1%) participants were from Karnataka, while 12 (8.9%) were from outside the state. 92 (68.1%) participants lived in urban areas, and 43 (31.9%) resided in rural areas. Most of the participants were from the higher SES (66/%) when compared to lower SES (34%).

For gender, a greater proportion of females were in the higher SES group (65.2%) than in the lower SES group (48.3%), although this difference was not statistically significant (p = 0.062). Marital status revealed significant differences (p = 0.022), with a greater percentage of married individuals in the lower SES group (77.5%) than in the higher SES group (58.7%). Smokeless tobacco use was more common in the lower SES group (12.4%) than in the higher SES group (2.2%), with this difference being statistically significant (p = 0.049). Education also showed significant variability across SES groups (p = 0.004), with the higher SES group showing a greater proportion of professional degrees (23.9%) compared to the lower SES group (4.5%). Occupation displayed the most significant association (p < 0.001), with a greater concentration of professionals in the higher SES group (28.3%) than in the lower SES group, where semiskilled and unskilled occupations were more common.

Most other variables, including diet, smoking habits, urban-rural residence, and various oral health conditions, were not significantly different between SES groups, with p-values generally above 0.05, suggesting that there was no strong association between these factors and SES in this sample.

The observations related to oral manifestations and their association with socioeconomic status (SES) reveal unique patterns. The prevalence of missing teeth is higher in lower SES groups (43.8%) compared to higher SES groups (28.3%), though the difference is not statistically significant (p = 0.078). The occurrence of dental restorations is also more frequent in the lower SES group (44.9%) than in the higher SES group (34.8%), but the difference remains insignificant (p = 0.256). Dental caries is slightly more common in the lower SES group (91%) than in the higher SES group (87%), with no significant difference (p = 0.464). Gingivitis shows a higher prevalence in the higher SES group (43.5%) compared to the lower SES group (34.8%), though this difference is not statistically significant (p = 0.326). Similarly, periodontitis is slightly more common in the higher SES group (23.9%) than in the lower SES group (22.5%), with no significant difference observed (p = 0.85).

Tooth wear patterns also vary between SES groups. Buccal tooth wear is higher in the lower SES group (36%) compared to the higher SES group (28.3%), but this difference is not significant (p = 0.369). Palatal tooth wear and occlusal tooth wear also do not show significant differences between SES groups, with p-values of 0.686 and 0.488, respectively. Regarding tooth surface appearance, the absence of abnormalities is slightly more common in the higher SES group (43.5%) than in the lower SES group (29.2%), though not significant (p = 0.348). Cracks in enamel are rare across both groups, and the rate of enamel and dentin wear remains similar (p = 0.688).

In terms of restoration outcomes, nil restoration cases are slightly more frequent in the higher SES group (58.7%) compared to the lower SES group (51.7%), but this difference is not significant (p = 0.735). Patterns of attrition, such as rounding of cusps and grooves or shiny facets, do not significantly differ between SES groups (p = 0.248). Attrition patterns like occlusal cupping or incisal grooving are rare and do not show a notable SES-related trend.

Soft tissue changes such as impressions on the cheek are more prevalent in the higher SES group (19.6%) than in the lower SES group (7.9%), but this difference is not statistically significant (p = 0.214). Pathological signs, including pain and sensitivity (50% in higher SES vs. 47.7% in lower SES) and functional problems, show minimal differences across SES groups, with no significant p-values. Similarly, deterioration of dental aesthetics does not vary significantly between groups (p = 0.896). These observations highlight that while some oral health parameters show variations between SES groups, most differences are not statistically significant ( Table 1).

Table 1 presents a comparative analysis of various demographic, behavioral, and clinical characteristics across different SES groups, SES III/IV (lower SES) and SES I/II (higher SES).

Binary logistic regression analysis was performed to predict higher SES in relation to findings of tooth morphology and diseases. In this analysis, the outcome being studied is the likelihood of belonging to a higher socioeconomic status (SES) score of III or IV than to a lower SES score of I or II. The regression results highlight several key factors influencing SES classification ( Table 2).

Sex shows a marginal association, where males have lower odds of being in the higher SES category (OR = 0.326, p = 0.053). Marital status is significantly associated with SES, as single individuals are 6.5 times more likely to be in the higher SES group than are married individuals (OR = 6.498, p = 0.011). Location/residency (Urban/Rural) did not significantly show any effect on SES (OR = 2.202, p = 0.373 and OR = 1.009, p = 0.988, respectively). The presence of certain habits also did not significantly affect SES (OR = 1.330, p = 0.815), smoking (OR = 4.653, p = 0.133) or diet (vegetarians vs. nonvegetarians, OR = 6.039, p = 0.161). Similarly, the presence of caries-related problems was not strongly associated with SES (OR = 1.150, p = 0.873).

Among the dental variables, specific tooth surface conditions were significantly associated: individuals with “Smooth Silky Shiny” tooth surfaces were less likely to belong to a higher SES group (OR = 0.081, p = 0.020), as were those with increased incisal translucency (OR = 0.049, p = 0.011). Soft and hard tissue impressions on the cheek significantly increased the odds of being in the higher SES category (OR = 5.237, p = 0.044). Finally, age and other specific oral conditions such as tooth defects Tooth defects and tooth wear were not significantly associated with SES status.

In summary, single marital status and cheek impressions are associated with higher odds of belonging to a higher SES group, whereas certain tooth surface conditions, particularly smooth and translucent surfaces, are linked with lower odds of higher SES classification.

Discussion

Socioeconomic status (SES) represents the relative position of individuals, families, or groups within a societal hierarchy based on access to valued goods like wealth, social recognition, and privileges.⁷ It is a multidimensional construct encompassing income, educational attainment, occupation, and quality of personal care, including oral health maintenance.⁸ SES significantly impacts health outcomes, with lower SES associated with greater health issues, including dental problems due to limited healthcare access, poor nutrition, and low health literacy.^4,9 Teeth and their associated characteristics, along with demographic information, can provide insights into an individual’s SES, aiding in identification by narrowing potential datasets on the basis of socioeconomic factors which could aid in forensic investigations.¹⁰

The modified Kuppuswamy scale, introduced in 1981 and updated in 2024, categorizes SES based on education, occupation, and monthly income of the head of the family. It classifies individuals into upper, upper-middle, lower-middle, upper-lower, or lower classes, but limitations exist, particularly in distinguishing joint versus nuclear families and its urban-centric focus.^5,11 SES also influences education, with higher SES groups more likely to attain professional degrees due to fewer financial constraints and greater awareness of the benefits of education. Occupation is another critical factor, with higher SES groups predominantly engaged in professional roles, while lower SES groups often work in semi-skilled or unskilled jobs.

Marital status: In our study, we found that individuals with lower socioeconomic status (SES) were more prevalent in terms of marital status. Individuals with higher SES, delay marriage and childbirth to focus on their education and careers.¹² Marital status can be an indirect indicator of socioeconomic position, as it can be associated with factors such as income, social support, and access to healthcare.

Residence (Urban/Rural): It is generally understood that a place of residence (urban/rural) can indirectly influence SES. The reasons are as follows: a) access to education and employment opportunities often differs between urban and rural areas, b) cost of living and income levels can vary significantly between these locations and c) availability and quality of healthcare services may also differ. These factors can contribute to socioeconomic disparities between urban and rural populations. Therefore, while the sources focus primarily on the impact of individual-level socioeconomic factors, it is important to acknowledge that a place of residence can play a complex and multifaceted role in shaping both SES and health outcomes.¹³ Most of the study participants were from urban areas, as our institution is situated in an urban environment, regardless of whether they belong to higher or lower socioeconomic status even though it was statistically insignificant.

Education: Research shows that socioeconomic status (SES) plays a significant role in educational outcomes, with the higher SES group showing a greater proportion of professional degrees than the lower SES group. Notably, parents with higher SES are more likely to send their children to attain higher degrees. This could be because they can afford as they do not have any financial restraints and are more knowledgeable about education than people of lower SES.¹⁴

Occupation: Displayed the most significant association, with a greater concentration of professionals in the higher SES group than in the lower SES group, where semiskilled and unskilled occupations were more common.

Smokeless tobacco: Various studies have highlighted the correlation between SES and health behaviors, such as smokeless tobacco use, which is more prevalent among lower SES groups.^15,16 Tobacco use is closely related to SES.¹⁷ The consumption of tobacco is more prevalent among the lower impoverished in India.¹⁸ The various oral health issues observed associated with the use of tobacco products were staining of teeth, tooth wear, tooth loss, dental caries, edentulousness. Additionally, tobacco use contributes to the buildup of plaque and calculus, with exposure of tooth root surface, periodontal pocket formation, increasing the risk of periodontitis, especially in the front teeth. Other issues include tobacco pouch keratosis, various potentially malignant oral disorders, and an increased risk of oral squamous cell carcinoma.^19,20It is also noted that tobacco consumption is declining more rapidly among people with higher SES than among those with when compared to the lower SES²¹ reflecting better awareness and access to cessation resources.

Oral findings: Dental caries (DC): More commonly seen in people with lower SES.^4,22,23 This could be because Individuals with lower SES often have poor oral hygiene practices and increase susceptibility to dental caries (DC). Though statistically insignificant in some studies, lower SES groups consistently exhibit higher dental caries prevalence, which is linked to factors like poor education, income constraints, and lack of awareness about oral health.

Edentulism: Partial or complete edentulism was more common in individuals with lower SES, these findings are similar to those of our study but statistically insignificant. They attributed the reason for edentulousness to lack of awareness and financial constraints, education and occupation as the root cause, hence, they would have opted for extraction of teeth.^24,25

Restorations: Although statistically insignificant in our study, we observed that even individuals with lower SES had gotten tooth restored. This could be due to most of our patients were from urban area where almost the 3/4^th dentist of India reside.²⁶ Dental institutions in India provide community-based dental camps in rural areas which spread awareness about dental health hand also provide dental treatment either free of cost or at minimal rates.

Periodontal diseases: Individuals with lower socioeconomic status tended to report more advanced symptoms of periodontal disease, including gingival swelling, whereas those with higher socioeconomic status were more likely to report early-stage symptoms, such as gingival bleeding.^27–29 These findings were similar to those of our study.

Tooth wear: The lower socioeconomic group was found to be the most affected by tooth wear.^30,31 These findings were in line with our study although they were statistically insignificant. Possible explanations for this disparity include a lack of awareness, knowledge, and education regarding the factors that contribute to tooth wear.³²

Smooth silky shiny teeth are a sign of mineral loss and incisal translucency is a sign of enamel loss. Individuals with low socioeconomic status are more susceptible to demineralization because of differing priority needs, lower levels of education, and limited access to preventive programs.³³ These findings are similar to our observations. A systematic review and meta-analysis of observational studies performed by Entezami S(2021) revealed that tooth wear was greater in individuals with higher SES due to increased consumption of juices with high acidic contents.³⁴

Soft tissue changes: Impressions on the cheek significantly increase the odds of being in the higher SES category. This could be due to the stress related to higher SES as society rapidly evolves, as individuals encounter a variety of stressors, including those related to work, family, relationships, finances, socio-cultural issues, and health.³⁵ Hashibe M, Jacob BJ et al (2003)³⁶ reported that people with high income could have more people in their household especially in the Indian population which could affect cleanliness which lead to development of fungal and viral lesions, however,in their study they reported that oral lesions were more common in people with lower SES which was in accordance with the study done by Taruna T, Singh YP, et al. (2023).³⁷

Dental health indicators provide significant insights into SES. For example, dental caries is more common in lower SES groups, attributed to factors like poor nutrition and hygiene. Partial and complete edentulism are also more prevalent in lower SES populations, often due to financial constraints and lack of awareness, leading to extractions rather than restorations. However, urban populations, regardless of SES, show greater utilization of dental restorations, likely due to the concentration of dentists in cities and access to community-based dental camps offering low-cost treatments. Periodontal diseases further reflect SES disparities. Studies show that individuals from lower SES backgrounds report more severe periodontal issues, such as gingival swelling, while higher SES groups report milder symptoms like gingival bleeding, indicating earlier intervention.

Conclusion

Overall, SES plays a vital role in shaping health and lifestyle outcomes, influencing access to education, healthcare, and occupational opportunities. By understanding the socioeconomic roots of health disparities, researchers and policymakers can better target interventions to improve health equity. These findings also demonstrate the value of incorporating SES indicators, such as education, occupation, marital status, and residence, into forensic investigations to enhance the precision of identification processes.