Pulse oximetry: a useful test for evaluating pulp vitality in traumatized teeth

Background and Aim: Subjective pulp tests are not trustworthy, particularly in traumatized teeth, and may lead to inaccurate diagnosis. The use of an objective test such as pulse oximetry (PO) could be a more reliable method to properly evaluate pulp status in this condition. The aim of this study was to analyze the effectiveness of PO in determining pulp vitality in traumatized teeth based on oxygen saturation measurements (%SpO(2)). Subjects and methods: Fifty-nine permanent teeth that had undergone lateral luxation, and which were unresponsive to a cold spray test and were free from signs of necrosis, were selected and tested with PO at 7, 30 and 60 days after trauma. Results: Fifty-nine teeth were tested. At 7 days after trauma, 8 teeth had low rates of oxygenation, compared to 10 at 30 and 60 days. Low rates were defined as a saturation reading <= 77% SpO(2). These teeth were assigned to the pulp necrosis (PN) group. The other 49 teeth were either considered to have healthy pulps (HP) (saturation >= 90% SpO(2)) or were assigned to a pulpitis (PP) group (saturation >= 78 to <= 89% SpO(2)). The 10 non-responsive teeth were followed up for 1 year and all exhibited indications for endodontic treatment. The other 49 teeth (HP or PP) began to show positive responses to the cold spray (after 3-9 months of follow up). No significant differences (P < 0.05) were detected between the three periods analyzed, but % SpO(2) rates were significantly different (P < 0.01) between the groups (HP vs PP, HP vs PN and PP vs PN). Conclusions: PO can be extremely useful for the assessment of dental pulp status in traumatized teeth, particularly when these teeth do not show signs of PN and do not respond to cold tests.