Prospectively-collected, tooth-specific dosimetry correlated with adverse dental outcomes

doi:10.1016/j.oooo.2016.03.005

Oral Surgery, Oral Medicine, Oral Pathology and Oral Radiology

Volume 122, Issue 2, August 2016, Pages 158-163

https://doi.org/10.1016/j.oooo.2016.03.005 Get rights and content

Objectives

To correlate radiation dose to specific tooth-bearing portions of bone with adverse dental outcomes.

Study Design

Eighty-nine patients treated with intensity-modulated radiation therapy with or without chemotherapy had radiation dose to specific tooth-bearing portions of the mandible and the maxilla. Data were collected prospectively during treatment planning, which resulted in 2490 data points. These patients underwent a comprehensive dental intake evaluation that included measurement of pocket depths and were then followed up with serial dental evaluations for a median of 2.5 years (range 0.2–6.9 years).

Results

At the patient level, the 3-year risks of osteoradionecrosis (ORN) and periodontal disease were 2.5% and 36.6%, respectively. For any individual tooth, the risks of ORN and periodontal disease were 0.1% and 5.1%, respectively, at 3 years. Radiation dose to individual tooth–bearing portions of bone was correlated with ORN development (P = .0165). Periodontal disease also demonstrated a significant, but more gradual, dose response (P = .0395).

Conclusions

Adverse dental outcomes directly correlate with increased tooth-specific doses.

Section snippets

Materials and Methods

In this study, which was approved by the Internal Review Board, we performed a retrospective analysis of dental outcomes in 89 patients treated with IMRT to a median dose of 7000 cGy (5800–7200 cGy) with or without chemotherapy between 2008 and 2014. The study was conducted in accordance with the ethical standards of the Helsinki Declaration for human subjects. The specifics of our IMRT prescription process have been previously reported.¹² Patients were excluded from the study if they did not

Results

The median dose to the mandibular or maxillary tooth-bearing portions of bone was 3100 cGy (range 206–7200 cGy). Two hundred forty-three teeth received greater than 5000 cGy and 79 received greater than 6000 cGy. Figure 1 represents a histogram of radiation dose to tooth-bearing sites.

Four hundred twenty-nine teeth were extracted from 59 patients before radiation. Subsequently, an additional 56 teeth in nine patients were extracted after radiation. Postradiation dental extractions were

Discussion

RT is an important treatment modality utilized in a large percentage of patients with head-and-neck cancer. Improved surgical and radiation techniques, coupled with an emerging cohort of patients with more favorable prognosis for human papilloma virus–associated cancers, has led to higher cure rates than in previous eras.¹³ With higher cure rates, there is increased opportunity for patients to manifest late effects of radiation.

ORN is the most reported dental complication in the literature.

Conclusions

We present the first tooth-specific dosimetric correlation between dose and adverse dental events. Attentive radiation treatment planning has the potential to reduce dental complications, potentially sparing toxicity and saving cost in the growing population of survivors of head and neck cancer. Moderate doses that were previously thought to be associated with low risk may place patients at increased risk of periodontal disease.

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Cited by (10)

Compliance with oral hygiene and dietary advice for the prevention of post-radiotherapy dental disease among head and neck cancer patients – a qualitative study
2023, Journal of Dentistry
To elicit head and neck cancer (HANC) patients’ views about their oral health and to identify potential issues regarding compliance with clinical oral hygiene and dietary advice for the prevention of post-radiotherapy dental disease.
A purposive sample of twelve HANC patients between 6- and 12-months post-radiotherapy were recruited to undergo a semi-structured interview with a qualitative researcher. A pre-piloted topic guide was used to frame each interview. Qualitative data were analysed via thematic analysis.
Data were categorised into four main themes – ‘How HANC patients perceive oral health’, ‘Cancer diagnosis and cancer care pathway’, ‘Impact of oncology treatment (radiotherapy, surgery, and chemotherapy)’, and ‘Post-oncology treatment recovery’, with 14 subthemes. Oral health was viewed as an important component of HANC patients’ overall physical and mental health post-treatment. Patients’ non-compliance with adequate oral hygiene practice was related to oral mucositis, a “burning” sensation associated with high fluoride toothpaste, forgotten or inconsistent clinical advice, and an inadequate supply of preventive oral hygiene products. The potentially highly cariogenic nature of prescribed nutritional supplements for patients at risk of malnutrition did not tend to be communicated to patients in advance of their prescription.
Adequate oral health is essential for the overall physical and mental well-being of post-treatment HANC patients. Non-compliance with preventive clinical advice increases the risk of post-treatment oral health deterioration and was related to miscommunication, inadequate supplies of oral hygiene products, and treatment-related oral discomfort.
Post-treatment HANC patients are at increased risk of dental disease. Educational and behavioural techniques should be employed to enhance patients’ compliance with clinical oral hygiene and dietary advice for the prevention of post-radiotherapy dental disease. Patients should be informed about the potentially highly cariogenic nature of nutritional supplements, and these patients should undergo frequent dental recall. Clinical advice regarding oral hygiene and dietary practices needs to be given consistently to HANC patients by different specialists of the HANC multidisciplinary team.
Artificial Intelligence-Guided Prediction of Dental Doses Before Planning of Radiation Therapy for Oropharyngeal Cancer: Technical Development and Initial Feasibility of Implementation
2022, Advances in Radiation Oncology
Citation Excerpt :
After adjustment for dental status (dentate vs postextraction), patients who developed ORN had larger volumes of the mandible exposed to high doses of radiation (>50 Gy). Another prospective study confirmed that >50 Gy to individual teeth increased the risk for ORN.22 Thus, a threshold of 50 Gy remains as a commonly used clinical reference point driving the decision on whether to enact pre-RT prophylactic extractions.4
The aim was to develop a novel artificial intelligence (AI)–guided clinical decision support system, to predict radiation doses to subsites of the mandible using diagnostic computed tomography scans acquired before any planning of head and neck radiation therapy (RT).
A dose classifier was trained using RT plans from 86 patients with oropharyngeal cancer; the test set consisted of an additional 20 plans. The classifier was trained to predict whether mandible subsites would receive a mean dose >50 Gy. The AI predictions were prospectively evaluated and compared with those of a specialist head and neck radiation oncologist for 9 patients. Positive predictive value (PPV), negative predictive value (NPV), Pearson correlation coefficient, and Lin concordance correlation coefficient were calculated to compare the AI predictions to those of the physician.
In the test data set, the AI predictions had a PPV of 0.95 and NPV of 0.88. For 9 patients evaluated prospectively, there was a strong correlation between the predictions of the AI algorithm and physician (P = .72, P < .001). Comparing the AI algorithm versus the physician, the PPVs were 0.82 versus 0.25, and the NPVs were 0.94 versus 1.0, respectively. Concordance between physician estimates and final planned doses was 0.62; this was 0.71 between AI-based estimates and final planned doses.
AI-guided decision support increased precision and accuracy of pre-RT dental dose estimates.
Pre-radiotherapy dental extractions in patients with head and neck cancer: a Delphi study
2020, Journal of Dentistry
Citation Excerpt :
Unfortunately, even with radiotherapy dose-fractionation, radiation treatment can damage normal tissues [6], and this may result in adverse side-effects such as mucositis [7], trismus [8], salivary gland hypofunction [9], dental caries [10], periodontal disease [11], and osteoradionecrosis [12]. The incidence of dental caries in post-radiotherapy HNC patients has been estimated at 29% [13], and between 18-68% of HNC patients suffer from post-radiotherapy periodontitis [14–19]. HNC patients are primarily at increased risk of post-radiotherapy dental caries due to the indirect effects of radiation (e.g. hyposalivation), however, structural damage to the teeth, such as enhanced enamel porosity, may also be contributory [20–22].
To gain a consensus from consultants in restorative dentistry about the types of teeth that should be extracted from head and neck cancer patients (HNC) pre-radiotherapy.
Literature- and clinician-informed questionnaires were emailed to an ‘expert panel’ of consultants (n = 24/28; 86%) in the United Kingdom (UK) and Ireland on three consecutive occasions (Delphi rounds). The results of Round 1 were used to revise the questionnaire that was distributed in Round 2, and this procedure was repeated for Round 3. During Rounds 2 and 3, participants were asked to indicate, on a 5-point Likert scale, their level of agreement with a series of statements on the types of teeth that should be extracted pre-radiotherapy. The target level of consensus for each statement was 70%.
In Round 2, there was consensus-agreement for 69 of 102 statements (i.e. ≥ 70% of participants rated ‘agree’ or ‘strongly agree’ to the relevant statement). Consensus agreement was also achieved for 20 of 28 statements in Round 3. Therefore, a total of 89 consensus statements are presented that illuminate the decision-making process for the pre-radiotherapy extraction of molar, premolar, and anterior teeth with periodontal pocketing, furcation disease, mobility, caries, tooth-wear, apical disease, or other pathology.
The statements represent the consensus professional views of participated consultants in restorative dentistry in the UK and Ireland regarding the types of teeth that should be extracted from HNC patients pre-radiotherapy. The results provide a platform for the development of future guidelines.
Pre-radiotherapy dental assessments for head and neck cancer patients are considered mandatory. This study presents different criteria that should be considered for the treatment planning of these patients in relation to pre-radiotherapy extractions, according to the collective consensus opinion of participated consultants in restorative dentistry in the UK and Ireland.
Optimising volumetric arc radiotherapy for dental rehabilitation in oropharynx cancer – A retrospective dosimetry review and feasibility planning study
2018, Oral Oncology
Citation Excerpt :
Furthermore Restorative Dentists are more concerned with the dose to the subsections where reconstructive implants will be inserted, namely the anterior mandible. Previous studies have attempted to address this by publishing retrospective dose distributions on either a tooth-by-tooth basis or a mandibular volume basis [12–15]. Whilst useful, they lack a shared definition of regions of interest, in particular the anterior mandible.
To assess the dosimetry to dentally relevant substructures within the mandible/maxilla, establish the predictors of increased mean anterior mandible dose and assess the feasibility of rationale optimisation of dose to the anterior mandible (AM) volume to aid reconstructive dental surgery planning, where the AM is a critical structure.
In a cohort of radically treated oropharynx cancer patients we conducted a retrospective dosimetry analysis of mandible/maxilla volumes, created using a published atlas. Comparisons of mean AM dose and clinical parameters between groups were tested using Wilcoxon rank-sum and Kruskal-Wallis tests. A multivariate linear regression model was created to assess independent predictors of increased mean AM dose. Patients with a mean AM dose over 37.5 Gy were included in feasibility planning study to test the hypothesis that it is possible to safely limit the dose whilst maintaining dose tolerances for other organs at risk.
57 patients were included. Median AM mean dose was 32.2 Gy (IQR 27.7–38.7). T stage, N stage and inclusion of Level 1B were significantly associated with increased mean AM dose. Only T stage (p = .0132) and Level Ib inclusion (p = .018) remained significant in the linear regression model. 88% of plans, all of which included Level Ib, were successfully re-optimised without breaching accepted constraints.
Oropharynx cancer patients with advanced T stage and who require Level Ib treatment receive increased mean AM dose, potentially limiting surgical dental rehabilitation options. The majority of patients can be optimised safely with appropriate AM contouring.
Delayed tongue necrosis simultaneous with bilateral osteoradionecrosis of the jaw secondary to head and neck irradiation
2017, Oral Surgery, Oral Medicine, Oral Pathology and Oral Radiology
Citation Excerpt :
The onset of ORN may be related to any type of trauma or may occur spontaneously.15,16 Tooth extraction is the type of trauma most frequently related to the development of ORN.11,15-20 Tongue necrosis in association with ORN secondary to head and neck irradiation has not been reported in the literature.
We present a rare case of massive tongue necrosis occurring simultaneously with bilateral osteoradionecrosis (ORN) of the jaw in a patient with a history of treatment, including surgery and postoperative radiotherapy, for a retromolar trigone carcinoma 8 years earlier. There is a distinct possibility that the extractions and administration of local anesthesia with a vasoconstrictor contributed to the onset of ORN; together, these events may have influenced the blood supply to the tongue. A glossectomy was performed after hyperbaric oxygen therapy. One month after the surgical procedure, the patient responded satisfactorily to the treatment, showing significant improvement in speech and oral food intake, as well as significant decrease in lingual pain. Although the simultaneous occurrence of these oral complications is rare, the practitioner must be aware of the factors that instigate ORN and compromise vasculature as well as the clinical signs of tongue necrosis. Additionally, the possibility of tongue necrosis secondary to irradiation of the head and neck should be taken into consideration when an irradiated patient undergoes tooth extractions under local anesthesia with agents containing epinephrine.
Dental extraction, intensity-modulated radiotherapy of head and neck cancer, and osteoradionecrosis: A systematic review and meta-analysis
2022, Strahlentherapie und Onkologie

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Oral medicineProspectively-collected, tooth-specific dosimetry correlated with adverse dental outcomes

Objectives

Study Design

Results

Conclusions

Section snippets

Materials and Methods

Results

Discussion

Conclusions

Oral Surg Oral Med Oral Pathol Oral Radiol

Lancet Oncol

Int J Radiat Oncol Biol Phys

J Oral Maxillofac Surg

Int J Radiat Oncol Biol Phys

Int J Radiat Oncol Biol Phys

Oral Surg Oral Med Oral Pathol Oral Radiol

Int J Oral Maxillofac Surg

Int J Radiat Oncol Biol Phys

Oral Oncol

Radiother Oncol

Oral medicine
Prospectively-collected, tooth-specific dosimetry correlated with adverse dental outcomes