ESTRO 2024 - Abstract Book

S1261

Clinical - Head & neck

ESTRO 2024

1 Rajiv Gandhi Cancer Institute and Research Centre, Radiation Oncology, New Delhi, India. 2 PDM Dental College and Research Institute, Department of Conservative Dentistry and Endodontics, Bahadurgarh, India

Purpose/Objective:

There is decrease in blood flow and the subsequent hypoxia and anoxia causing an inhibition of myelinic fibers and leading to an immediate reduction of tooth sensitivity after radiotherapy (RT). The aim of this study was to determine the effects of RT on the pulp of posteriorly located teeth in patients with oropharyngeal cancer undergoing high dose curative radical RT.

Material/Methods:

Patients with oropharyngeal cancer with noncarious intact vitals teeth, teeth that responded positively to cold testing and electric pulp testing (EPT), and having no history of spontaneous pain or pain on percussion were recruited in the study. All underwent radical RT to a dose of atleast 66 Gy. Posteriorly located teeth one from each quradrant were examined. Pulp sensitivity was checked by cold test (difluorodichloromethane at minus 50 degree celcius) and EPT. Recording were done at the commencement of RT, at 4 months, 1 year and 2 years after the completion of RT.

Results:

182 teeth were examined in 50 patients. Pulpal responsiveness was found to be declining progressively during the follow up. A significant difference was observed in the number of positive responses from the commencement of RT to 2 years after the completion of RT. A significant correlation was observed between the maximum dose per tooth in each quadrant and decreased pulp sensitivity at 2 years after completion of RT.

Mean pulp testing at all-time points are shown in Table below.

Pulp test mean (standard deviation)

Time points

1st quadrant teeth

2nd quadrant teeth

3rd quadrant teeth

4th quadrant teeth

Pulp testing prior to commencement of RT Pulp testing at 4 months post RT Pulp testing at 1 year post RT Pulp testing at 2 years post RT

9.21 (2.17)

9.23 (2.76)

9.17 (2.71)

9.56 (2.78)

27.65 (6.76)

23.92 (6.01)

25.11 (6.54)

24.90 (6.12)

46.12 (8.91)

47.20 (9.01)

46.79 (9.02)

48.33 (9.65)

59.65 (12.22)

62.77 (14.62)

64.22 (13.76)

64.54 (14.55)

F value p value

161.21 <0.001

153.76 <0.001

146.60 <0.001

159.01 <0.001

Conclusion: