Dent et irradiation : denture et conséquences sur la denture de la radiothérapie des cancers de la tête et du cou

The EORTC QLQ43 and FACT H&N questionnaires of quality of life at 1 and 5 years after treatment and dental care in head and neck cancer patients: a pilot study

PURPOSE

This study aimed to examine health-related quality of life (HRQoL) in head and neck cancer patients at 1 and 5 years after successful treatment of their tumors, and to explore the usefulness of 2 instruments for assessing the need of dental care services.

METHODS

This cross-sectional pilot study included 20 adult patients with head and neck cancer who completed the Functional Assessment of Cancer Therapy-Head and Neck (FACT H&N) Symptom Index and the European Organization for Research and Treatment of Cancer Quality of Life Head and Neck Module (EORTC QLQ-H&N43) after 1 and 5 years of treatment.

RESULTS

Mean (standard deviation, SD) scores of the FACT H&N Symptom Index were higher (better HRQoL) at 5 years than at 1 year (24.1 [4.4] vs. 21.1 [6.4]; p = 0.236). Only three of the ten items of FACT H&N (swallow, pain in mouth/throat or neck, and solid foods) evaluated oral health. In the EORTC QLQ-H&N43 questionnaire, scores were lower at 5 years (better HRQoL) in almost all multi- and single-item symptoms. This questionnaire includes four multi-item scales (pain in the mouth, social eating, swallowing, and problems with teeth) measuring dental and orthodontic needs.

CONCLUSION

HRQoL in patients with head and neck cancer improved with the length of follow-up. The EORTC QLQ-H&N43 has more items addressing oral health compared to the FACT H&N Symptom Index and may be more adequate to assess the need of dental therapy in clinical practice.

Dental Care in Head and Neck Cancer Patients Undergoing Radiotherapy

External beam radiotherapy is an integral part of the management of head and neck cancer. Radiotherapy for head and neck cancer lead to many treatment-related toxicities, including a wide range of dental morbidities. These complications depend on the various patient and treatment-related factors. Patients with poor oral hygiene, pre-existing periodontal disease, and the conventional mode of radiotherapy delivery are major factors leading to acute and severe late dental problems. Most of the complications are preventable with proper oral and dental care before, during and after radiotherapy. Pre radiotherapy dental evaluation to diagnose patients with potential risk and timely intervention can reduce long-term morbidities like carries, osteoradionecrosis, etc., thereby improving patients' quality of life. This article highlights the various aspects of dental care and management in head neck cancer patients before, during and after radiation therapy.

Poor dental condition is a factor of imbalance of the nutritional status at the outset of management of head and neck cancer

OBJECTIVES

To determine whether deterioration of dental condition at the outset of management of head and neck cancer (HNC) is a nutritional risk and whether social deprivation is a cause of the poor dental condition observed in HNC patients.

MATERIAL AND METHODS

A nutritional assessment form (NAF) and the Nutrition Risk Index (NRI) were used to standardize the nutritional status of 108 patients at the outset of management of HNC (2017-2019). The NAF includes assessment of weight loss over the past 3 months, the amount and difficulty of food intake, and the presence of digestive disorders. Dental condition was assessed by the decayed, filled, and missing teeth acopre (DFM) index and the masticatory coefficient (MC). Dental status and social deprivation were correlated with the EPICES score.

RESULTS

A correlation was found between the extent of weight loss and dental condition. The MC was higher in absence of weight loss (46% vs. 27%, p = 0.03) and the DMF lower when weight loss was less than 5% (22.3 vs. 26.9 if > 5% loss of weight, p = 0.005). No correlation was found between dental status and nutritional status. Social deprivation was associated with a lower MC (26% vs. 50%, p < 0.001).

CONCLUSION

Dental condition is a risk factor for weight loss at the outset of management of HNC but is not a determinant of nutritional status. Clinical relevance Dental condition is no longer considered simply as a source of potential complications after radiotherapy but also as an important factor for nutritional status.

Impact of non-compliance with oral care on radiation caries in head and neck cancer survivors

PURPOSE

A cross-sectional study was performed to quantify radiation caries (RC); explore the possible influence of various covariates like elapsed time since radiotherapy, cancer site and stage, treatment modality(ies), grades of xerostomia (GOX), and inter-incisal mouth opening on RC; and also to estimate the unmet treatment needs in head and neck cancer (HNC) survivors, where personal and professional oral care was neglected before and after completion of the treatment.

METHODOLOGY

Clinical status of the dentition was recorded using decayed missing filled surface/decayed missing filled teeth (DMFS/DMFT) index. Patients were grouped according to the respective covariates, and relevant statistical analysis was performed considering p value ≤ 0.05 as statistically significant.

RESULTS

Eighty nine patients, 72 males and 17 females, with a mean age of 52.37±11.19 (range 18-70) years were included in this study. Overall, 85% (76/89) and 78% (29/37), 87.5% (35/40), and 100% (12/12) of patients reporting within 1, 1-3, and 3-5 years after RT, respectively, were affected with RC. The mean DMFS/DMFT score, range, and standard deviation in the included patients up to 5 years post-RT were 61.12/15.99, 0-128/0-28, and 36.608/8.66, respectively. Unmet treatment needs concerning dental decay were 97%. A statistically significant difference was found between the mean DMFS with elapsed time since radiotherapy and different GOX, respectively.

CONCLUSION

Oral health will be worse, treatment needs will be high, and limitations to performing desirable treatment will be numerous in HNC patients, where the oral care component of their treatment is ignored. Future studies are required to identify the true relationship between various risk factors and the development and progression of RC.

Ability to Propose Optimal Prosthetic Rehabilitation can be Improved by Discussion between the Dentist and Radiation Oncologist Regarding Upstream Dosimetry

Objective Improvement of dental rehabilitation for patients who have undergone radiation therapy requires knowledge of the dose in the maxillary and mandible bones.

Materials and Methods Forty-three patients with head and neck cancers underwent evaluation for dental rehabilitation before radiation treatment dosimetry. The delivered dose to the maxilla and mandible was determined. From the dose data in the literature, three levels of risk of implant failure were defined. According to the delivered doses, the authors calculated the percentage of patients who could be fully rehabilitated with an implant, as proposed by the dentist before radiation planning.

Results Before dosimetry calculation, all of the completely edentulous arches and 94 partially edentulous (PESs) sextants could be optimally rehabilitated. After dose calculation, among the 14 arches of 7 patients who were completely edentulous, according to the mean and maximal delivered doses, 11 arches (78.6%) and 7 arches (50%) could receive an optimal prosthesis, respectively. For the three patients, who were PESs but with one arch that was completely edentulous, according to the mean and maximal delivered doses, one arch for each dose condition could receive an optimal prosthesis. Among the 94 PESs sextants, according to the mean and maximal delivered doses, 41 (43.6%) and 24 (25.5%) sextants could receive an optimal prosthesis, respectively.

Conclusion By determining the sites of implantation before dosimetry, the radiation oncologist could shield specified areas, potentially improving the possibilities for dental rehabilitation. The dialogue between the dentist and the radiation oncologist can improve the possibilities for implants and decrease the risk of unsafe implantation.

Radiation Therapy for Oral Cavity and Oropharyngeal Cancers

Radiotherapy is a key therapeutic modality used in the treatment of oral cavity and oropharyngeal cancers, whether as definitive treatment or postoperatively for those with high-risk factors after surgery. Although radiotherapy is a proven, effective treatment of cancer control, it can result in significant acute and late toxicities. Pretreatment patient education, supportive care, and posttreatment adherence to rehabilitative and preventive care can help mitigate toxicities. Advances in radiation delivery, such as through continued technological advances, or novel approaches to customizing radiation dose and volume, to maximize the therapeutic efficacy while minimizing side effects, are warranted.

Tensile Bond Strengths of Two Adhesives on Irradiated and Nonirradiated Human Dentin

The aim of this study was to assess the effect of radiotherapy on bond efficiency of two different adhesive systems using tensile bond strength test. Twenty extracted teeth after radiotherapy and twenty nonirradiated extracted teeth were used. The irradiation was applied in vivo to a minimal dose of 50 Gy. The specimens of each group were randomly assigned to two subgroups to test two different adhesive systems. A three-step/etch-and-rinse adhesive system (Optibond FL) and a two-steps/self-etch adhesive system (Optibond XTR) were used. Composite buildups were performed with a nanohybrid composite (Herculite XTR). All specimens were submitted to thermocycling ageing (10000 cycles). The specimens were sectioned in 1 mm(2) sticks. Microtensile bond strength tests were measured. Nonparametric statistical analyses were performed due to nonnormality of data. Optibond XTR on irradiated and nonirradiated teeth did not show any significant differences. However, Optibond FL bond strength was more effective on nonirradiated teeth than on irradiated teeth. Within the limitations of an in vitro study, it can be concluded that radiotherapy had a significant detrimental effect on bond strength to human dentin. However, it seems that adhesive choice could be adapted to the substrata. According to the present study, the two-steps/self-etch (Optibond XTR) adhesive system tested could be more effective on irradiated dentin compared to three-steps/etch-and-rinse adhesive system (Optibond FL).

[Dental state in patients with head and neck cancers]

In France, in 2005, there were approximately 16,000 new cases of head and neck cancer. These cancers have an unfavourable prognosis: the survival rates at 3 and 10 years are 50% and 10% respectively. The consumption of alcohol and tobacco is the most important risk factor; in some countries HPV infection was identified as a risk factor of head and neck tumours. Furthermore, a poor oral hygiene seems to raise this risk. We found many decay and periodontium problems in patients with an upper aerodigestive tract cancer. An evaluation of dental state is necessary before any cancer treatment. Treatments by radiotherapy engender noxious effects: hypocellular, hypovascularization, hypoxie of the irradiated tissues, which lead to immediate and chronically oral complications such as mucositis, fibrosis, xerostomia, decay, or osteoradionecrosis. An oral follow-up of these patients can prevent these complications, or reduce the severity of oral complications, and promote a good oral state.

Dental management of patients irradiated for head and neck cancer

Patients undergoing radiation therapy as either primary, adjuvant, combination therapy or palliative management of head and neck malignancies are prone to a range of dental complications. Strategies for prevention and management of such complications may be controversial. This article aims to highlight the current understanding and management of the dental needs for patients before, during and after radiation therapy.

[Constraints of the dentist are consistent with the results of an optimal irradiation with modulated intensity in N0 oropharyngeal cancer]

PURPOSE

We compared intensity-modulated radiotherapy and 3D-conformal irradiation in oropharyngeal cancers according to the requirement of dentists.

MATERIAL AND METHODS

From the files of seven patients with cancer of the oropharynx, two dosimetry plannings for 3D-conformal radiotherapy and intensity-modulated radiotherapy with tomotherapy were performed. The dose distributions in the target volumes and organs at risk in relation to the dental sphere were compared.

RESULTS

For the planning target volume of the primitive tumour sites, average values of V95%, D2%, D98% and of the conformal index were statistically in favour of tomotherapy. For the planning target volume of node areas, averages values of V95%, D2%, D98% were statistically in favour of tomotherapy. For ipsi- and controlateral parotide glands, average values of V15Gy, V26Gy, V30Gy, V40Gy were significantly lower for tomotherapy. For the submaxillary glands, average values of mean doses and V40Gy were statistically in favour of tomotherapy. For the buccal cavity, the average values of V45Gy were statistically in favour of tomotherapy. For ipsi- and controlateral masseter muscles, the average values of mean doses were statistically in favour of tomotherapy. For the ipsi- and controlateral temporomandibular joints, average values of mean doses and V60Gy were statistically in favour of tomotherapy. For mandibular bone, average values of mean doses and V40Gy, V50Gy, V60Gy and V70Gy were statistically in favour of tomotherapy. For maxillary bone, average values of V40Gy, V50Gy and V60Gy were statistically in favour of tomotherapy.

CONCLUSION

The radiation oncologist can constrain the intensity-modulated radiotherapy dosimetry to the needs of dentists to prevent or improve dental care and quality of life.

Effect of X-ray irradiation on the elastic strain evolution in the mineral phase of bovine bone under creep and load-free conditions

Both the load partitioning between hydroxyapatite (HAP) and collagen during compressive creep deformation of bone and the HAP residual strain in unloaded bone have been shown in previous synchrotron X-ray diffraction studies to be affected by the X-ray irradiation dose. Here, through detailed analysis of the X-ray diffraction patterns of bovine bone, the effect of X-ray dose on (i) the rate of HAP elastic strain accumulation/shedding under creep conditions and (ii) the HAP lattice spacing and average root mean square (RMS) strain under load-free conditions are examined. These strain measurements exhibit three stages in response to increasing X-ray dose. Up to ∼75 kGy (stage I) no effect of dose is observed, indicating a threshold behavior. Between ∼75 and ∼300 kGy (stage II) in unloaded bone the HAP d-spacing increases and the RMS strain decreases with dose, indicating strain relaxation of HAP. Furthermore, under constant compressive load creep conditions, the rate of compressive elastic strain accumulation in HAP decreases with increasing dose until, at ∼115 kGy, it changes sign, indicating that the HAP phase is shedding load during creep deformation. These stage II behaviors are consistent with HAP-collagen interfacial damage, which allows the HAP elastic strain to relax within both the loaded and unloaded samples. Finally, for doses in excess of ∼300 kGy (stage III, measured up to 7771 kGy) the HAP lattice spacing and RMS strain for load-free samples and the rate of HAP elastic strain shedding for crept samples remain independent of dose, suggesting a saturation of damage and/or stiffening of the collagen matrix due to intermolecular cross-linking.

[Revisiting the dose-effect correlations in irradiated head and neck cancer using automatic segmentation tools of the dental structures, mandible and maxilla]

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.

Compliance with fluoride custom trays in irradiated head and neck cancer patients

PURPOSE

The purpose of this study is to assess compliance with fluoride gel custom trays in irradiated head and neck cancer patients.

METHODS AND MATERIALS

One hundred fifty-five consecutive patients on remission following radiation therapy of head and neck cancers were assessed retrospectively for dental care practices prior to radiation and prospectively for long-term compliance with custom trays from November 2009 to January 2010. A five-item questionnaire was filled in by patients in the waiting room, and a 15-item questionnaire by the physician in charge during the corresponding follow-up visit.

RESULTS

Ten percent of patients were edentulous at inclusion. Among dentate patients, 17% had total extractions. With a mean follow-up of 24 months, 19% of patients used custom trays for over a year. Primary stage, age, and tobacco consumption were correlated with compliance with custom trays. More than half of dentate patients developed carious lesions, and 8% had stage 1-3 osteoradionecrosis of the whole population of edentulous and dentate patients.

CONCLUSION

Compliance with custom trays was poor in this series. Specific postirradiation dental care follow-up visits and education have demonstrated their utility in the era of 2D irradiation. We currently advocate an 18-month compliance with custom trays in IMRT patients on the basis of the Parsport trial, after which we assess the quality of salivary recovery before recommending prolonged use or interruption. Data with innovative irradiation techniques are however required.

Dentalmaps: automatic dental delineation for radiotherapy planning in head-and-neck cancer

PURPOSE

To propose an automatic atlas-based segmentation framework of the dental structures, called Dentalmaps, and to assess its accuracy and relevance to guide dental care in the context of intensity-modulated radiotherapy.

METHODS AND MATERIALS

A multi-atlas-based segmentation, less sensitive to artifacts than previously published head-and-neck segmentation methods, was used. The manual segmentations of a 21-patient database were first deformed onto the query using nonlinear registrations with the training images and then fused to estimate the consensus segmentation of the query.

RESULTS

The framework was evaluated with a leave-one-out protocol. The maximum doses estimated using manual contours were considered as ground truth and compared with the maximum doses estimated using automatic contours. The dose estimation error was within 2-Gy accuracy in 75% of cases (with a median of 0.9 Gy), whereas it was within 2-Gy accuracy in 30% of cases only with the visual estimation method without any contour, which is the routine practice procedure.

CONCLUSIONS

Dose estimates using this framework were more accurate than visual estimates without dental contour. Dentalmaps represents a useful documentation and communication tool between radiation oncologists and dentists in routine practice. Prospective multicenter assessment is underway on patients extrinsic to the database.