Diet, tooth loss, and dental calculus in Guizhou adults (2024-2025)

This study aimed to explore the correlation between dietary structure characteristics and the prevalence of tooth loss and dental calculus in adults residing in Huishui Area of Guizhou Province.

A total of 4,216 permanent adults aged ≥18 years were recruited using multi-stage stratified random sampling. Face-to-face questionnaire surveys collected dietary intake information, and standardized oral clinical examinations recorded tooth loss and dental calculus grading. Binary logistic regression (for tooth loss) and ordinal logistic regression (for dental calculus severity) were applied, adjusting for age, sex, education, income, brushing frequency, flossing use, smoking and alcohol consumption.

Tooth loss rate was 31.45% (mean 1.7 teeth/person); dental calculus detection rate was 71.00% (Grade I: 34.00%, Grade II: 24.00%, Grade III: 12.00%). Multivariate analysis identified weekly meat intake (OR = 1.20, 95%CI: 1.02-1.42), weekly nut intake (OR = 0.61, 95%CI: 0.46-0.82), daily dairy intake (OR = 0.62, 95%CI: 0.46-0.83), weekly fruit intake frequency (OR = 0.60, 95%CI: 0.44-0.81), weekly vegetable intake frequency (OR = 2.80, 95%CI: 2.00-3.91), and daily vegetable weight (OR = 0.68, 95%CI: 0.53-0.88) as independent factors for tooth loss (all p < 0.05). For dental calculus severity, weekly meat intake (cumulative OR = 1.06, 95%CI: 1.02-1.10), daily dairy intake (cumulative OR = 0.89, 95%CI: 0.86-0.93), weekly fruit frequency (cumulative OR = 0.94, 95%CI: 0.90-0.97), weekly vegetable frequency (cumulative OR = 1.05, 95%CI: 1.01-1.10), and daily vegetable weight (≥500 g vs. <150 g: cumulative OR = 0.80, 95%CI: 0.74-0.86) were significant (all p < 0.05).

Unbalanced dietary structure is a key modifiable risk factor. The "3-4-500" dietary model provides an evidence-based framework for oral health promotion in underserved populations.