Impact of Tooth Preservation or Replacement on Diet Quality: Modified Treatment Policies Approach

To examine the impact of emulated natural tooth preservation or dental rehabilitation scenarios on diet quality among older adults in the United States, assessing what diet quality would be if people's dentition or rehabilitation status were improved.

Data from 2606 participants aged ≥ 60 across four NHANES cycles (2011-2018) were analyzed. Dentition status and prosthetic rehabilitation were clinically assessed, and diet quality was measured using the Healthy Eating Index (HEI)-2020. The modified treatment policies (MTP) framework was used to emulate hypothetical interventions of retaining natural teeth or providing prosthetic rehabilitation. Odds ratios (OR) for achieving better diet quality under each scenario were estimated using doubly robust targeted maximum likelihood estimation (TMLE).

If all participants retained ≥ 25 teeth, the likelihood of achieving better HEI scores increased by 51% (OR = 1.51, 95% CI: 1.32-1.69). In a pragmatic scenario where each dentition group was shifted up by one level (edentulous → 1-9 teeth, 1-9 teeth → 10-19 teeth, 10-19 teeth → 20-25 teeth, 1-9 teeth → ≥ 25 teeth), the population had a 20% higher likelihood of achieving better diet quality (OR = 1.22, 95% CI: 1.14-1.29). Prosthetic rehabilitation yielded comparatively smaller effects, with rehabilitation in individuals with < 25 teeth improving the likelihood of better diet quality by 8% (OR = 1.08, 95% CI: 1.03-1.12).

The present observational study suggests that preserving natural teeth has a stronger population-level impact on diet quality than prosthetic rehabilitation replacing missing teeth in older adults.