Radiotherapy (RT) plays an important role in the treatment of patients with head and neck cancer. Clinical changes in the surrounding healthy tissue are often inevitable. The deleterious effects on the bones of the jaws have been considered a contraindication for rehabilitation with dental implants. However, in recent years, the installation of implants in irradiated patients has been consolidated as a valuable treatment option. The aim of this study was to evaluate the effect of RT on the survival of osseointegrated dental implants in patients with head and neck cancer. The applied methodology involved an electronic search in the MEDLINE database during the last five years.  We identified 67 scientific documents related to the keywords: "radiotherapy", "dental implants" and "head and neck cancer", four articles were selected and reviewed, composing this analysis.  It is concluded that dental implants installed in irradiated bone in the oral cavity have a high survival rate, 97.37%, provided that rigorous monitoring is instituted in RT in order to be successful in the long term. The percentage of dental implant failures tended to be higher in the group of irradiated patients.

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The precision in the dose values delivered in irradiation processes is essential for the efficiency and quality control of these processes. Radiochromic films can be used to record doses and the calibration of these films must be performed so that they can be used as dosimeters. The planning and control of the radiation released in a process allows to adjust the desired dose in the irradiated object. The photons in the primary beam interact with the matter of the object and the beam energy is attenuated due to these interactions. The attenuation depends on the characteristics of the beam and the composition of the irradiated matter. When a beam of photons propagates on an object, it tends to deposit more energy close to the surface and after reaching the maximum dose value, it decreases the dose values with depth. The films used in this work are of the Gafchromic External Beam Therapy (EBT) type, insensitive to visible light and can be prepared in places where sunlight and artificial light exists. Like many other dosimeters, which follow certain protocols, radiochromic films can provide an absolute dose measurement. Radiochromic films are characterized by their linearity, reproducibility, uniformity, sensitivity, and stability after irradiation. For the realization of the experiments, a part of the film to be irradiated was removed designated as background (BG). BG represents a piece of radiochromic film that will not change and reflects changes in film absorption in relation to environmental conditions such as temperature, visible light and scanning light, for example and that must be handled from it way that the film radiated. In this work, irradiations of a solid water phantom were performed using a source of cesium-137 with the deposition of a maximum absorbed dose value of 2.0 Gy. The phantom was placed 1,0 m far from the source collimator. Radiochromic films were placed inside the phantom to obtain the depth variation dose profile and axial dose profiles measured at 1.0 cm depth in the phantom. The dose variation profile in depth allowed to verify that the maximum dose value happened at a depth between 10 and 13 mm, very close to the surface due to the beam energy range (keV). The axial profiles presented a flatness of about 9.4 cm with a total field of 12 cm in diameter.

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Radiotherapy is an established method of cancer treatment and is widely applied to control this disease. Medical Linear Accelerators (LINAC) are widely used in modern radiotherapy due to their flexibility and high therapeutic reliability. Traditionally, national and international codes of conduct provide guidelines on dosimetry with a reference field of 10x10 cm², considering that for larger fields, dosimetric parameters are well defined and can be accurately measured. In this work, a LINAC X-ray beam of 6 MV was used to irradiate a solid water phantom, using fields of 10x10 and 5x5 cm². X-ray beam was generated in a 6MV linear accelerator (linac) model Synergy Platform from the manufacturer Elektra. Radiochromic film sheets were used to record dose profiles inside the solid water phantom. For irradiation of the phantom loaded with the film, it was positioned twice 1.0 m away from the focus of the X-ray beam for both field sizes. In the first irradiation, the phantom was exposed laterally to obtain the longitudinal dose variation profile and in the second irradiation, the phantom was irradiated frontally. The longitudinal profile of absorbed dose obtained showed the maximum dose value at 1.30 cm depth for both fields. Axial dose profiles were recorded at 1 cm depth, and showed a plateau in the axis Y for both fields. The plateau for the field of 10x10 cm² in the axis X presented a depression in the central area and that did not happen in the 5x5 cm² field.