Pulp oxygen saturation measurement as a diagnostic tool for assessing pulp status in primary teeth: A systematic review and meta-analysis.

Objectives: This study aimed to determine the mean oxygen saturation values (SpO₂) in primary teeth using pulse oximetry.

Materials and methods: This comprehensive literature search on pulse oximeter used for primary teeth in determining pulp vitality using MeSH terms in four electronic databases, including PubMed, Scopus, Cochrane Library, and Ovid^SP, from January 1990 to January 2022. Studies reported the sample size and the mean SpO₂ values (with standard deviations) for each tooth group were included. The quality assessment of all the included studies was done using the Quality Assessment of Diagnostic Accuracy Studies-2 tool and the Newcastle-Ottawa Scale. The meta-analysis included studies reporting means and standard deviations of SpO₂ values. The I² statistics were used to determine the degree of heterogeneity among the studies.

Results: A total of 90 studies were identified, of which five met the eligibility criteria that were qualified for the systematic review, and among them, three were included in the meta-analysis. All five included studies were of low quality due to the high risk of bias related to the patient selection, index test, and uncertainties about outcome valuation. In the meta-analysis, the mean fixed-effect measure of oxygen saturation in the pulp of primary teeth was 88.45% (confidence interval: 83.97%-92.93%).

Conclusion: Though most of the available studies were of poor quality, the SpO₂ in the healthy pulp can be established (minimum saturation, 83.48%) in primary teeth. Reference values established might help clinicians to assess changes in pulp status.