Reference Values for Pulse Oximetry Testing in Permanent Teeth: A Systematic Review and Meta-Analysis

Pulse oximetry is an accurate diagnostic method for assessing the condition of the dental pulp; however, the normal oxygen saturation levels for each tooth type are yet to be clearly defined.

This systematic review and meta-analysis aims to answer the question: What are the reference values for pulse oximetry testing in permanent teeth with healthy pulps and complete root formation?

The present review followed the PRISMA recommendations. Systematic searches were conducted in the Cochrane Library, Embase, PubMed, Scopus and OpenGrey electronic databases, for studies published until September 2025, without any restrictions on the year or language of publication. The following descriptors were combined in each database: 'Endodontics', 'Dental Pulp', 'Pulse Oximetry', 'Oximeter', 'Oxygen Saturation', 'Pulp Oxygen Saturation'. Only clinical studies were included. Two independent authors were responsible for study selection and data extraction. In cases of disagreement, a third author was responsible for the final decision. The risk of bias of the included studies was assessed using the ROBINS-I tool, RoB 2.0, JBI Critical Appraisal Checklist for Analytical Cross-Sectional Studies, or QUADAS-2, depending on the study design.

The initial screening of databases yielded 1772 studies, with 322 duplicates excluded. From the 1450 eligible papers, 55 met the inclusion criteria and were selected for full-text reading, resulting in the selection of 35 studies. Five additional studies were included from reference lists of the selected papers. Therefore, a total of 40 studies were included in the present review. Meta-analyses of the oxygen saturation values for each maxillary and mandibular tooth type were conducted using a random-effects model. A total of 3537 teeth from twenty studies were analysed. The highest mean random-effect measure of pulp oxygen saturation was 91.73% (95% CI, 90.33%-93.13%) in mandibular incisors, and the lowest was 86.26% (95% CI, 81.90%-90.62%) in maxillary lateral incisors.

Based on the available evidence, reference values for pulp oxygen saturation in permanent teeth with complete root development and healthy pulps ranged from 86.26% to 91.73%. These findings support the clinical relevance of establishing preliminary reference values for pulp oximetry and highlight the need for further standardisation before routine clinical implementation.

This study was registered in the PROSPERO database: CRD42023437995.