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Pretreatment dental screening aims to locate and eliminate oral foci of infection in order to eliminate local, loco-regional, or systemic complications during and after oncologic treatment. An oral focus of infection is a pathologic process in the oral cavity that does not cause major infectious problems in healthy individuals, but may lead to severe local or systemic inflammation in patients subjected to oncologic treatment. As head and neck radiotherapy patients bear a lifelong risk on oral sequelae resulting from this therapy, the effects of chemotherapy on healthy oral tissues are essentially temporary and reversible. This has a large impact on what to consider as an oral focus of infection when patients are subjected to, for example, head and neck radiotherapy for cancer or intensive chemotherapy for hematological disorders. While in patients subjected to head and neck radiotherapy oral foci of infection have to be removed before therapy that may cause problems ultimately, in patients that will receive chemotherapy such, so-called chronic, foci of infection are not in need of removal of teeth but can be treated during a remission phase. Acute foci of infection always have to be removed before or early after the onset of any oncologic treatment.

Pretreatment dental screening aims to locate and eliminate oral foci of infection in order to eliminate local, loco‐regional, or systemic complications during and after oncologic treatment. An oral focus of infection is a pathologic process in the oral cavity that does not cause major infectious problems in healthy individuals, but may lead to severe local or systemic inflammation in patients subjected to oncologic treatment. As head and neck radiotherapy patients bear a lifelong risk on oral sequelae resulting from this therapy, the effects of chemotherapy on healthy oral tissues are essentially temporary and reversible. This has a large impact on what to consider as an oral focus of infection when patients are subjected to, for example, head and neck radiotherapy for cancer or intensive chemotherapy for hematological disorders. While in patients subjected to head and neck radiotherapy oral foci of infection have to be removed before therapy that may cause problems ultimately, in patients that will receive chemotherapy such, so‐called chronic, foci of infection are not in need of removal of teeth but can be treated during a remission phase. Acute foci of infection always have to be removed before or early after the onset of any oncologic treatment.

PURPOSE: To evaluate the feasibility and efficacy of a novel concept of early loaded (ie, within 2 weeks) implant-supported fixed dental prostheses (ISFDP) for patients who underwent mandibular reconstruction. MATERIALS AND METHODS: All patients requiring mandibular reconstruction between July 2013 and March 2016 at AZ Sint-Jan Brugge-Oostende AV were screened for dental rehabilitation according to the proposed concept. Of 17 patients, 10 were eligible for inclusion. Clinical and radiologic assessments of implant integration and prosthetic survival were performed at 6, 12, 24, and 36 months. Patient satisfaction was assessed prior to and after prosthetic rehabilitation using the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaires Core 30 and Head & Neck 35, as well as a visual analog scale. RESULTS: Ten patients received mandibular reconstructive surgery for an oral cavity tumor (n = 6), osteoradionecrosis (n = 3), or medication-related osteonecrosis of the jaw (n = 1). Implants were placed within an average of 6 (2 to 21) months postsurgery in a one-stage procedure. Prosthetic rehabilitation was achieved within 2 weeks in 8 of the 10 patients. Two patients received their ISFDP delayed due to postoperative complications. Implant integration and prosthetic outcome at a maximum of 36 months of follow-up were successful in 7 of the 10 patients. At that time, two patients had passed away, while one patient had the ISFPD removed because of graft necrosis after radiotherapy. Patient satisfaction was high, with significant improvement after dental rehabilitation in comparison to mandibular reconstruction alone. CONCLUSION: The present concept offers a feasible and fast prosthetic rehabilitation that improves patient quality of life. ispartof: INTERNATIONAL JOURNAL OF PROSTHODONTICS vol:32 issue:2 pages:162-173 ispartof: location:United States status: published

Hypoxia—a common feature of the majority of solid tumors—is a negative prognostic factor, as it is associated with invasion, metastasis and therapy resistance. To date, a variety of methods are available for the assessment of tumor hypoxia, including the use of positron emission tomography (PET). A plethora of hypoxia PET tracers, each with its own strengths and limitations, has been developed and successfully validated, thereby providing useful prognostic or predictive information. The current review focusses on [18F]-HX4, a promising next-generation hypoxia PET tracer. After a brief history of its development, we discuss and compare its characteristics with other hypoxia PET tracers and provide an update on its progression into the clinic. Lastly, we address the potential applications of assessing tumor hypoxia using [18F]-HX4, with a focus on improving patient-tailored therapies.

Hypoxia-a common feature of the majority of solid tumors-is a negative prognostic factor, as it is associated with invasion, metastasis and therapy resistance. To date, a variety of methods are available for the assessment of tumor hypoxia, including the use of positron emission tomography (PET). A plethora of hypoxia PET tracers, each with its own strengths and limitations, has been developed and successfully validated, thereby providing useful prognostic or predictive information. The current review focusses on [18F]-HX4, a promising next-generation hypoxia PET tracer. After a brief history of its development, we discuss and compare its characteristics with other hypoxia PET tracers and provide an update on its progression into the clinic. Lastly, we address the potential applications of assessing tumor hypoxia using [18F]-HX4, with a focus on improving patient-tailored therapies.

Purpose: This study investigated whether Magnetic Resonance image biomarkers (MR-IBMs) were associated with xerostomia 12 months after radiotherapy (Xer(12m)) and to test the hypothesis that the ratio of fat-to-functional parotid tissue is related to Xer(12m). Additionally, improvement of the reference Xer(12m) model based on parotid gland dose and baseline xerostomia, with MR-IBMs was explored.Methods: Parotid gland MR-IBMs of 68 head and neck cancer patients were extracted from pre-treatment T1-weighted MR images, which were normalized to fat tissue, quantifying 21 intensity and 43 texture image characteristics. The performance of the resulting multivariable logistic regression models after bootstrapped forward selection was compared with that of the logistic regression reference model. Validity was tested in a small external cohort of 25 head and neck cancer patients.Results: High intensity MR-IBM P90 (the 90th intensity percentile) values were significantly associated with a higher risk of Xer(12m). High P90 values were related to high fat concentration in the parotid glands. The MR-IBM P90 significantly improved model performance in predicting Xer(12m) (likelihood-ratio-test; p = 0.002), with an increase in internally validated AUC from 0.78 (reference model) to 0.83 (P90). The MR-IBM P90 model also outperformed the reference model (AUC = 0.65) on the external validation cohort (AUC = 0.83).Conclusion: Pre-treatment MR-IBMs were associated to radiation-induced xerostomia, which supported the hypothesis that the amount of predisposed fat within the parotid glands is associated with Xer(12m). In addition, xerostomia prediction was improved with MR-IBMs compared to the reference model. (C) 2018 The Authors. Published by Elsevier B.V.

PURPOSE: Intensity-modulated radiation therapy (IMRT) has changed radiation treatment of head and neck cancer (HNC). However, it is still unclear if and how IMRT changes oral morbidity outcomes. In this prospective study, we assessed the outcome of reducing post-IMRT sequelae by means of pre-radiation dental screening and eliminating oral foci.METHODS: All consecutive dentate patients > 18 years, diagnosed with primary oral or oropharyngeal carcinoma, referred for pre-treatment dental screening between May 2011 and May 2013, were included and followed for 2 years. Patients were treated with IMRT or IMRT with chemotherapy (CHIMRT). Dental screening data, demographic data, and data on oral sequelae during follow-up were recorded. Diagnosed oral foci were treated before start of the radiation therapy.RESULTS: Oral foci were found in 44/56 (79%) patients, consisting predominantly of periodontal breakdown. Bone healing problems after radiotherapy occurred more often in patients with periodontal pockets ≥ 6 mm at baseline (19 vs. 4% in patients with pockets < 6 mm). Osteoradionecrosis developed in 4/56 patients (7%) during follow-up. In line with this observation, multiple logistic regression analysis showed that the periodontal inflamed surface area, which is higher in patients with more severe periodontal disease, predicted that a patient has a higher risk on developing osteoradionecrosis or bone healing problems (p = 0.028).CONCLUSIONS: Patients with severe periodontal disease before IMRT/CHIMRT are more prone to develop bone healing problems post-radiotherapy.

In healthy subjects, dental implants have evolved to be a common therapy to solve problems related to stability and retention of dentures as well as to replace failing teeth. Although dental implants are applied in medically compromised patients, it is often not well known whether this therapy is also feasible in these patients, whether the risk of implant failure and developing peri-implantitis is increased, and what specific preventive measures, if any, have to be taken when applying dental implants in these patients. Generally speaking, as was the conclusion by the leading review of Diz, Scully, and Sanz on placement of dental implants in medically compromised patients (JDent, 41, 2013, 195), in a few disorders implant survival may be lower, and the risk of a compromised peri-implant health and its related complications be greater, but the degree of systemic disease control outweighs the nature of the disorder rather than the risk accompanying dental implant treatment. So, as dental implant treatment is accompanied by significant functional benefits and improved oral health-related quality of life, dental implant therapy is a feasible treatment in almost any medically compromised patient when the required preventive measures are taken and follow-up care is at a high level.

Background and purpose: Current models for the prediction of late patient-rated moderate-to-severe xerostomia (XER12m) and sticky saliva (STIC12m) after radiotherapy are based on dose-volume parameters and baseline xerostomia (XERbase) or sticky saliva (STICbase) scores. The purpose is to improve prediction of XER12m, and STIC12m with patient-specific characteristics, based on CT image biomarkers (IBMs).Methods: Planning CT-scans and patient-rated outcome measures were prospectively collected for 249 head and neck cancer patients treated with definitive radiotherapy with or without systemic treatment. The potential IBMs represent geometric. CT intensity and textural characteristics of the parotid and sub mandibular glands. Lasso regularisation was used to create multivariable logistic regression models, which were internally validated by bootstrapping.Results: The prediction of XER12m could be improved significantly by adding the IBM "Short Run Emphasis" (SRE), which quantifies heterogeneity of parotid tissue, to a model with mean contra-lateral parotid gland dose and XERbase. For STIC12m, the IBM maximum CT intensity of the submandibular gland was selected in addition to STICbase and mean dose to submandibular glands.Conclusion: Prediction of XER12m and STIC12m was improved by including IBMs representing heterogeneity and density of the salivary glands, respectively. These IBMs could guide additional research to the patient-specific response of healthy tissue to radiation dose. (C) 2016 The Authors. Published by Elsevier Ireland Ltd.

BACKGROUND AND PURPOSE: Current prediction of radiation-induced xerostomia 12months after radiotherapy (Xer12m) is based on mean parotid gland dose and baseline xerostomia (Xerbaseline) scores. The hypothesis of this study was that prediction of Xer12m is improved with patient-specific characteristics extracted from (18)F-FDG PET images, quantified in PET image biomarkers (PET-IBMs).PATIENTS AND METHODS: Intensity and textural PET-IBMs of the parotid gland were collected from pre-treatment (18)F-FDG PET images of 161 head and neck cancer patients. Patient-rated toxicity was prospectively collected. Multivariable logistic regression models resulting from step-wise forward selection and Lasso regularisation were internally validated by bootstrapping. The reference model with parotid gland dose and Xerbaseline was compared with the resulting PET-IBM models.RESULTS: High values of the intensity PET-IBM (90th percentile (P90)) and textural PET-IBM (Long Run High Grey-level Emphasis 3 (LRHG3E)) were significantly associated with lower risk of Xer12m. Both PET-IBMs significantly added in the prediction of Xer12m to the reference model. The AUC increased from 0.73 (0.65-0.81) (reference model) to 0.77 (0.70-0.84) (P90) and 0.77 (0.69-0.84) (LRHG3E).CONCLUSION: Prediction of Xer12m was significantly improved with pre-treatment PET-IBMs, indicating that high metabolic parotid gland activity is associated with lower risk of developing late xerostomia. This study highlights the potential of incorporating patient-specific PET-derived functional characteristics into NTCP model development.

Radiation-induced hyposalivation is still a major problem after radiotherapy for head and neck cancer. Current and promising new thoughts to reduce or salvage radiation damage to salivary gland tissue are explored. The main cause underlying radiation-induced hyposalivation is a lack of functional saliva-producing acinar cells resulting from radiation-induced stem cell sterilization. Current methods to prevent that damage are radiation techniques to reduce radiation-injury to salivary gland tissue, surgical techniques to relocate salivary glands to a region receiving a lower cumulative radiation dose, and techniques to make salivary gland cells more resistant to radiation injury. These preventive techniques cannot be applied in all cases, also reduce tumor sensitivity, or do not result in a sufficient amelioration of the dryness-related complaints. Therefore, alternative methods on techniques to salvage salivary glands that are damaged by radiation are explored with promising results, such as stem cell therapies and gene transfer techniques to allow the radiation-injured salivary gland tissue to secrete water.

Radiation-induced hyposalivation is still a major problem after radiotherapy for head and neck cancer. Current and promising new thoughts to reduce or salvage radiation damage to salivary gland tissue are explored. The main cause underlying radiation-induced hyposalivation is a lack of functional saliva-producing acinar cells resulting from radiation-induced stem cell sterilization. Current methods to prevent that damage are radiation techniques to reduce radiation-injury to salivary gland tissue, surgical techniques to relocate salivary glands to a region receiving a lower cumulative radiation dose, and techniques to make salivary gland cells more resistant to radiation injury. These preventive techniques cannot be applied in all cases, also reduce tumor sensitivity, or do not result in a sufficient amelioration of the dryness-related complaints. Therefore, alternative methods on techniques to salvage salivary glands that are damaged by radiation are explored with promising results, such as stem cell therapies and gene transfer techniques to allow the radiation-injured salivary gland tissue to secrete water.