[Revisiting the dose-effect correlations in irradiated head and neck cancer using automatic segmentation tools of the dental structures, mandible and maxilla]. / Dentalmaps : un outil pratique pour chirurgiens dentistes et radiothérapeutes pour l'estimation de la dose reçue aux dents, mandibule et maxillaire et du risque de complications postradiques en cas de soins dentaires.

PURPOSE: Manual delineation of dental structures is too time-consuming to be feasible in routine practice. Information on dose risk levels is crucial for dentists following irradiation of the head and neck to avoid postextraction osteoradionecrosis based on empirical dose-effects data established on bidimensional radiation therapy plans. MATERIAL AND METHODS: We present an automatic atlas-based segmentation framework of the dental structures, called Dentalmaps, constructed from a patient image-segmentation database. RESULTS: This framework is accurate (within 2 Gy accuracy) and relevant for the routine use. It has the potential to guide dental care in the context of new irradiation techniques. CONCLUSION: This tool provides a user-friendly interface for dentists and radiation oncologists in the context of irradiated head and neck cancer patients. It will likely improve the knowledge of dose-effect correlations for dental complications and osteoradionecrosis.

[Teeth and irradiation: dental care and treatment of osteoradionecrosis after irradiation in head and neck cancer]. / Dent et irradiation: prévention et traitement des complications dentaires de la radiothérapie y compris l'ostéoradionécrose.

Pre-irradiation dental care depends on teeth health, fields and dose of irradiation, compliance to fluorides, cessation of tobacco and psychosocial cofactors. Dental care aims at preventing complications and preserving the quality of life (eating, speech, and aesthetics). The role of hyperbaric oxygenotherapy for the prevention of osteoradionecrosis after teeth removal on the mandibula in areas receiving 50 Gy or more is still controversial. Medical treatments may be sufficient for early stages of osteoradionecrosis (antibiotics, pain killers, non-steroidal anti-inflammatory drugs as well as clodronate, vitamin E, pentoxifyllin). However, reconstructive surgery should not be delayed in advanced stages of osteoradionecrosis. New irradiation techniques are changing dose distributions and therefore require close collaboration between odonto-stomatologists and radiation oncologists to define the best dental care.

[Teeth and irradiation in head and neck cancer]. / Dent et irradiation: denture et conséquences sur la denture de la radiothérapie des cancers de la tête et du cou.

Pre-irradiation dental care depends on teeth health, fields and dose of irradiation, compliance to fluorides, cessation of tobacco and psychosocial cofactors. Dental care aims at preventing complications and preserving the quality of life (eating, speech and aesthetics). Approximately 11% of patients do not require any pre-irradiation dental care. Dental complications vary from slight colorations of the teeth to major complication such as osteoradionecrosis. Osteoradionecrosis rates vary from 1 to 9%, and may be decreased by using a 21-day delay between extractions and irradiation, provided that it does not postpone cancer treatment, with a dose-dependent risk (<6% if <40 Gy; 14% between 40 et 60 Gy; > or =20% if >60 Gy). Osteoradionecrosis occurs spontaneously (35%), mostly involves the mandibula (85%).

A remnant tooth in an edentulous patient.

OBJECTIVES: We describe a case of an unusual remnant tooth located in the paranasal sinus in a head and neck cancer patient. CASE REPORT: A 72-year patient with a history of T3N2aM0 oropharyngeal cancer treated with chemoradiation came for systematic post-therapeutic multidetector-CT reformation (MDCT) examination. MDCT scan multi planar reformation revealed a well-limited high-density mass in his maxillary sinus, which proved to be a remnant molar tooth. Physical examination and CT imaging were performed at 26 months. Local malignancy, fungal ball and persistent oroantral fistula were ruled out. CONCLUSION: The physio-pathogenesis of oroantral fistula (OAF) and causes of intra sinusal tooth as well as therapy are discussed in this article.

Low-energy He/Ne laser in the prevention of radiation-induced mucositis. A multicenter phase III randomized study in patients with head and neck cancer.

Use of the low-energy helium-neon laser (LEL) appears to be a simple atraumatic technique for the prevention and treatment of mucositis of various origins. Preliminary findings, and significant results obtained for chemotherapy-induced mucositis in a previous phase III study, prompted a randomized multicenter double-blind trial to evaluate LEL in the prevention of acute radiation-induced stomatitis. Irradiation by LEL corresponds to local application of a high-photon-density monochromatic light source. Activation of epithelial healing for LEL-treated surfaces, the most commonly recognized effect, has been confirmed by numerous in vitro studies. The mechanism of action at a molecular and enzymatic level is presently being studied. From September 1994 to March 1998, 30 patients were randomized. Technical specification: 60 mW (25 mW at Reims, 1 patient), He-Ne, wavelength 632.8 nm. The trial was open to patients with carcinoma of the oropharynx, hypopharynx and oral cavity, treated by radiotherapy alone (65 Gy at a rate of 2 Gy/fraction, 5 fractions per week) without prior surgery or concomitant chemotherapy. The malignant tumor had to be located outside the tested laser application areas (9 points): posterior third of the internal surfaces of the cheeks, soft palate and anterior tonsillar pillars. Patients were randomized to LEL or placebo light treatment, starting on the first day of radiotherapy and before each session. The treatment time (t) for each application point was given by the equation : t(s)= energy (J/cm2) x surface (cm2)/Power (W). Objective assessment of the degree of mucositis was recorded weekly by a physician blinded to the type of treatment, using the WHO scale for grading of mucositis and a segmented visual analogue scale for pain evaluation. Protocol feasibility and compliance were excellent. Grade 3 mucositis occured with a frequency of 35.2% without LEL and of 7.6% with LEL (P<0.01). The frequency of "severe pain" (grade 3) was 23.8% without LEL, falling to 1.9% with LEL (P<0.05). Pain relief was significantly reduced throughout the treatment period (weeks 2-7). LEL therapy is capable of reducing the severity and duration of oral mucositis associated with radiation therapy. In addition, there is a tremendous potential for using LEL in combined treatment protocols utilizing concomitant chemotherapy and radiotherapy.