Dosimetric evaluation of the effect of dental implants in head and neck radiotherapy

Dosimetric evaluation of the effect of dental implants in head and neck radiotherapy
Received 6 September 2004; revised 10 November 2004; accepted 13 November 2004. Ankara, Turkey
G??LHANE MILITARY MEDICAL ACADEMY. Available online 30 March 2005.
Julide Ozen DDS, PhDa, , , Bahar Dirican PhDb, Kaan Oysul MDc, Murat Beyzadeoglu MDb, Ozlem Ucok DDS, PhDd and Bedri Beydemir DDS, PhDe
Oral Surgery, Oral Medicine, Oral Pathology, Oral Radiology, and Endodontology
ScienceDirect
aAsistant Professor, Department of Prosthetic Dentistry, G??lhane Military Medical Academy, Ankara, Turkey
bAssociate Professor, Department of Radiation Oncology, G??lhane Military Medical Academy, Ankara, Turkey
cAssistant Professor, Department of Radiation Oncology, G??lhane Military Medical Academy, Ankara, Turkey
dAssistant Professor, Department of Oral Diagnosis and Radiology, G??lhane Military Medical Academy, Ankara, Turkey
eProfessor and Chairman, Department of Prosthetic Dentistry, G??lhane Military Medical Academy, Ankara, Turkey
Objective
The aim of the study was to examine the dose enhancement from scattered radiation at bone-dental implant interfaces during simulated head and neck radiotherapy.
Study design
Four cylindrical titanium dental implants with 3 different sizes and lengths were implanted into a human mandible in 4 different positions. Ionization measurements for 6 MV X, 25 MV X, and Co-60 gamma rays were done. Thermoluminescent dosimeter (TLD100) chips were used to measure radiation dose enhancement due to the scattered electrons from titanium and electronic disequilibrium at the tissue-metal interface.
Results
The results showed that for Co-60, there is a 21% maximum increase in dose to alveolar mandibular bone at the close proximity to the titanium. For 6-MV x-rays the dose enhancement increase was almost the same or slightly lower than for Co-60, while for 25-MV high-energy x-rays, dose enhancement was lower than that of others. This increase in dose enhancement fell off rapidly and became insignificant at 2 mm from the interface.
Conclusion
Total dose that may lead to osteoradionecrosis risk of the mandible is slightly but not significantly affected by the scattered dose of the dental implants of lower jaw in the radiation field exposed to 3 different radiation beams.
Reprint requests: Julide Ozen, DDS, PhD, Department of Prosthetic Dentistry, G??lhane Military Medical Academy, 06018, Etlik, Ankara, Turkey