Late Effects of Head and Neck Radiotherapy on Pulp Vitality Assessed by Pulse Oximetry

• Long-term effects of RT on teeth in the path of ionizing radiation were investigated.
• %SpO2 were measured 4-6 years after RT of intraoral and oropharyngeal tumors.
• No significant difference found in %SpO2 between experimental and control groups.

IntroductionRadiation therapy (RT) of malignant tumors in the head and neck area may have damaging effects on surrounding tissues. The aim of this investigation was to evaluate the long-term effects of ionizing radiation on pulp vitality by measuring pulp oxygenation levels (%SpO2) in patients with history of RT of intraoral and oropharyngeal tumors 4–6 years after treatment.MethodsIn an experimental group RT (n = 90, history of RT) and a control group CON (n = 90, no history of RT), pulp vitality was assessed by measuring %SpO2 by using pulse oximetry and pulp sensitivity by cold thermal testing. All anterior teeth without history of endodontic therapy of the participants in group RT were measured (n = 693), regardless of the quadrant and the irradiated area. An equal number of anterior teeth were tested in group CON.ResultsThere was no significant difference between the %SpO2 levels in group RT (92.7%; standard deviation, ± 1.83) and group CON (92.6%; standard deviation, ± 1.80). All teeth in RT and CON groups showed a positive response to the thermal test. All tested teeth were considered vital.ConclusionsPulp %SpO2 was found to be within normal limits 4–6 years after RT. This suggests that RT may not have a long-term influence on pulp vitality, and reported short-term changes in pulpal microcirculation because of RT may be temporary.