Comparison of In Vitro Dose Perturbation Effects of Amalgam, Composite Resin, Glass Ionomer Cement and Ketac Silver During Head and Neck Radiation with Photon Beam

Abstract

The most common oral manifestation from head and neck radiotherapy is mucositis. A part of complications is backscattering from metallic dental materials in radiation field, resulting in a dosage enhancement at the tissue-metal interface. The proper management of the patient’s restorative materials must be performed preoperatively to reduce these complications. This research compared the relative dose enhancement (RDE) in the different restorative materials (Amalgam, Composite resin, Glass ionomer cement and Ketac Silver®), the different tooth preparations (Class I, Class I other, Class II MOD, Cusp Tipping and Core build-up) and the location of ionizing chamber (buccal, occlusal, lingual surface). The dimension of controlled 20 teeth are as followed lower third molar, buccolingual width (10.41±0.82mm), mesiodistal width (11.28±0.72mm), dentin and enamel buccolingual width (1.5±0.5mm). The experiment is set using a modular radiation beam analyzer with at least 2 cm water as soft tissue equivalent material, 3 times irradiated with LINAC 6MV 200MU. The backscattering occurred in the amalgam filled tooth at the buccal and occlusal aspect in every preparation. The highest RDE occurring at the buccal aspect of cusp tipping amalgam filled tooth was 2.7%. In the lingual aspect, every preparation of amalgam filled tooth demonstrated lower RDE. The composite resin and glass ionomer cement produced low backscattering, while Ketac Silver® produced higher RDE. For any amalgam restorations in the radiation field, we recommended using the one-layer glass ionomer technique, which is suitable in preparing patient ahead of head and neck radiation. The recommended filling technique may decrease mucositis the adjacent area and improve the patient’s quality of life.