Risk of osteoradionecrosis after extraction of impacted third molars in irradiated head and neck cancer patients

Osteoradionecrosis incidence in pre-radiation teeth extractions: A prospective study

AIMS

To evaluate osteoradionecrosis (ORN) incidence in a cohort of patients undergoing tooth extraction (TE) before radiotherapy (RT) for head and neck cancers.

METHODS

The study protocol was approved by the Ethics Committee of Università Cattolica del Sacro Cuore (ID-2132) and registered at clinicaltrials.gov (ID: NCT04009161). TE was performed in case of signs of pericoronitis, periapical lesions, restorative impossibility, severe periodontitis. ORN was defined as exposed bone at an unhealed post-extraction socket in the absence of oncological recurrence. The RT plans were reviewed, and each post-extractive socket was contoured to calculate the received radiation dose.

RESULTS

In total, 156 patients with 610 TE were enrolled. The mean follow-up was 567 days. ORN was diagnosed in four patients (2.6% of patients and 0.7% of TE). Need for osteotomy and radiation dose at the extraction site were associated with ORN (OR for osteotomy: 21.9, 95% CI: 2.17-222.2, p = 0.009; OR for RT dose: 1.1, 95% CI: 1-1.15, p = 0.05).

CONCLUSIONS

TE appears to be a significant risk factor for ORN, particularly when osteotomy is required, and post-extraction sockets receive a high RT dosage. This study proposes a decision-making algorithm for TE and outlines a straightforward surgical protocol.

Efficacy of adjunctive modalities during tooth extraction for the prevention of osteoradionecrosis: A systematic review and meta-analysis

BACKGROUND

Jaw osteoradionecrosis (ORN) is a complication in patients with previous head and neck radiotherapy. Its incidence increases with dental extractions. Hence, this review aimed to evaluate the efficacy of adjunctive treatment modalities undertaken at the time of extraction in previous head and neck radiotherapy patients in preventing ORN.

METHODS

A systematic review was conducted, where studies with data on ORN incidence after extraction with or without adjunctive interventions were included. Meta-analyses were conducted to estimate the pooled prevalence of ORN per intervention and the pooled odds ratio for incidence of ORN between interventions.

RESULTS

In total, 1520 patients in 29 studies were included. Interventions identified were hyperbaric oxygen (HBO), pentoxifylline-tocopherol (PENTO), antibiotics (ABX), platelet-rich fibrin and photobiomodulation. The pooled prevalence of ORN for HBO (4.6%), PENTO (3.4%) and ABX (3.8%) was significantly lower than the Control (17.6%). For studies with direct comparisons between groups, HBO had lower but not significant odds of developing ORN than the Control (OR 0.27) and ABX (OR 0.57).

CONCLUSIONS

HBO, PENTO and ABX may reduce the incidence of ORN compared to no intervention. Given that all three have similar incidences of ORN, ABX may be the most cost-effective and accessible adjunctive modality.

Prevalence and Factors Influencing Post-Operative Complications following Tooth Extraction: A Narrative Review

Background

Complications from dental extractions may result in multiple post-operative visits and adversely affect the patient's life. Preventing complications may decrease post-operative morbidity for the individual as well as lower societal costs, such as lost time from work and healthcare costs.

Objectives

This narrative review aims to assess the prevalence and factors influencing post-operative complications following tooth extraction, helping clinicians minimise the risk. Data Sources. Cross-sectional studies. Study Eligibility and Participants. Patients undergoing dental extractions. Our exclusion criteria included in vitro studies, animal studies, terminally ill patients, and tooth loss not due to dental extraction. Literature was collected from "PubMed" and "Web of Science" through search criteria based on the "PICO" framework. Twenty articles were used to formulate a prevalence table, and 156 articles were included for the factors influencing complications. Study Appraisal and Synthesis Methods. This narrative review was reported using the SANRA (a scale for the quality assessment of narrative review articles) checklist. Due to the scope of our narrative review and its associated objectives, the quality of cross-sectional studies (AXIS) will be conducted from the studies outlining the prevalence.

Results

Alveolar osteitis appears to be the most prevalent post-operative complication following tooth extraction. Predisposing factors can be significant in their ability to alter the risk of postoperative complications, and clinicians should provide patient-centred care to mitigate this risk. Limitations. Due to the breadth of context, a systematic review was not feasible, as it may have introduced heterogeneity.

Conclusion

This narrative review has highlighted an array of factors which can influence the prevalence of post-operative complications. Future research would benefit from individually reporting post-operative complications, reducing the heterogeneity in definitions of the complications, and including greater detail on the predisposing factors studied.

Tooth extraction within 2 weeks before radiotherapy and osteoradionecrosis: A nationwide cohort study

OBJECTIVES

The theory of at least 2-week waiting period between tooth extraction and head and neck radiotherapy could reduce osteoradionecrosis remains controversial. Thus, this study examined the theory and associated factors.

MATERIALS AND METHODS

Data were retrieved from the National Health Insurance Research Database, Taiwan Cancer Registry Database, and Cause of Death Statistics. We included 24,353 patients with head and neck cancer who received radiotherapy from 2011 to 2017 and were followed up until 2019. The patients were divided into three groups: those undergoing tooth removal 2-8 weeks before radiotherapy, those undergoing tooth removal within 2 weeks before radiotherapy, and others. Confounding factors were clinical information, physical conditions, and risky habits. We used the Cox regression model to assess osteoradionecrosis risk.

RESULTS

No significant difference in osteoradionecrosis risk was observed between those undergoing tooth extraction within 2 weeks before radiotherapy and the other groups. An irradiation dose of ≥60 Gy, chemotherapy, tumor excision, post-radiotherapy tooth extraction, mandibulectomy, hyperlipidemia, and oral cavity as the tumor subsite were significantly positively associated with osteoradionecrosis risk.

CONCLUSION

A waiting period of ≥2 weeks between tooth extraction and radiotherapy did not significantly reduce osteoradionecrosis risk.

Utility of pre-chemoradiotherapy Pan-Immune-Inflammation-Value for predicting the osteoradionecrosis rates in locally advanced nasopharyngeal cancers

PURPOSE

The aim of this retrospective study was to explore whether pretreatment Pan-Immune-Inflammation-Value (PIV) measurements might predict the risk of mandibular osteoradionecrosis (ORN) in patients receiving concurrent chemoradiotherapy (CCRT) for locally advanced nasopharyngeal cancer (LA-NPC).

METHODS

The platelet, monocyte, neutrophil, and lymphocyte counts acquired on the first day of CCRT were used to compute pretreatment PIV levels: PIV = (Platelets × Monocytes × Neutrophils) ÷ Lymphocytes. Receiver operating characteristic curve analysis was used to determine the association between ORN rates and PIV levels. Spearman correlation analysis was used to examine the probable intergroup correlations. The potential link between the pretreatment PIV levels and the post-treatment ORN rates was determined as the primary objective.

RESULTS

21 (10.0%) of 210 eligible patients were diagnosed with ORN. The optimal pre-CCRT PIV cutoff was 833, which separated patients into two PIV groups with divergent ORN prevalence estimates: Group 1: PIV < 833 (N = 153), and Group 2: PIV ≥ 833 (N = 57). The comparison analysis found that the PIV ≥ 833 cohort had significantly higher ORN rates than the PIV < 833 cohort (29.8% vs. 2.6%; P < 0.001). Other characteristics linked to significantly higher ORN rates were the patient's continuing smoking, the use of the Three-dimensional conformal radiation therapy technique, the mean mandibular dose of ≥ 58.1 Gy, the number of tooth extractions before CCRT ≥ 4, and the presence of tooth extractions after CCRT. The independent importance of all factors on higher ORN occurrence rates were retained in multivariate analysis (P < 0.05).

CONCLUSIONS

Our findings revealed a strong link between aggravated inflammatory response and ORN genesis, with high pretreatment PIV levels related to significantly higher ORN rates.

The dental management of patients irradiated for head and neck cancer

Patients undergoing radiotherapy for head and neck cancers are prone to a range of dental complications, including mucositis, trismus, xerostomia, radiation caries and osteoradionecrosis. Specific considerations include the preventive, restorative and rehabilitative management of such patients, and the prevention and treatment of complications. This article aims to highlight the current understanding and management of dental needs for patients who have had or will undergo radiotherapy.

The predictive value of pretreatment hemoglobin-to-platelet ratio on osteoradionecrosis incidence rates of locally advanced nasopharyngeal cancer patients managed with concurrent chemoradiotherapy

BACKGROUND

This retrospective study aimed to investigate whether the pretreatment hemoglobin-to-platelet ratio (HPR) could predict the risk of osteoradionecrosis (ORN) in patients receiving concurrent chemoradiotherapy (C-CRT) for locally advanced nasopharyngeal carcinoma (LA-NPC).

METHODS

ORN cases were reported from the records of LA-NPC patients who had oral examinations before and after C-CRT. The pretreatment HPR values were calculated on the first day of C-CRT. The connection between HPR values and ORN occurrences was determined using receiver operating characteristic curve analysis. The primary endpoint was the relationship between the pretreatment HPR values and post-C-CRT ORN incidence rates, while secondary endpoints included the identification of other putative ORN risk factors.

RESULTS

We distinguished 10.9% incidences of ORN during the post-C-CRT follow-up period among 193 LA-NPC patients. The optimal cutoff for pre-C-CRT HPR was 0.48 that grouped the patients into two HPR groups with fundamentally different post-C-CRT ORN incidence rates: Group 1: HPR ≤ 0.48 (N = 60), and Group 2: HPR > 0.48 (N = 133). The comparative analysis indicated a significantly higher ORN incidence in HPR ≤ 0.48 group (30%; P < 0.001). The other factors associated with meaningfully increased ORN rates included the presence of pre-C-CRT ≥ 5 teeth extractions, mandibular volume receiving ≥ 64 Gy, post-C-CRT tooth extractions, mean mandibular dose ≥ 50.6 Gy, and C-CRT to tooth extraction interval > 5.5 months.

CONCLUSION

Low pretreatment HPR levels were independently and unequivocally linked to significantly increased incidence of ORN post-C-CRT. Pre-C-CRT HPR levels may be used to estimate the incidence of ORN and be useful for taking preventive and therapeutic measures in these patients such as monitoring oral hygiene with strict follow-up, avoidance of unnecessary tooth extractions, particularly after C-CRT, and use of more rigorous mandibular RT dose limits.

Pre-chemoradiotherapy low hemoglobin levels indicate increased osteoradionecrosis risk in locally advanced nasopharyngeal cancer patients

PURPOSE

We aimed to determine whether pretreatment hemoglobin (Hb) levels can predict the risk of osteoradionecrosis (ORN) in patients receiving concurrent chemoradiotherapy (CCRT) for locally advanced nasopharyngeal carcinoma (LA-NPC).

METHODS

ORN cases were identified from the records of LA-NPCs who had oral exams before and after CCRT. All Hb measurements were obtained on the first day of treatment. Receiving operating characteristic curve analysis was used to determine the relationship between Hb levels and ORN rates. The relationship between pretreatment Hb levels and ORN rates served as the primary endpoint, and secondary endpoints included the discovery of additional potential ORN risk factors.

RESULTS

Among the 263 eligible LA-NPCs, we identified 8.7% ORN cases. The ideal cutoff Hb before CCRT was 10.6 g/dL. It was revealed that HPR ≤ 10.6 group had a significantly higher ORN rate (32.5% vs. 1.5% for Hb > 10.6; P < 0.001). The mandibular V59.8 ≥ 36% Gy, pre-CCRT ≥ 4 tooth extractions, the presence of post-CCRT tooth extractions, and the time of post-CCRT tooth extractions > 8 months were the other factors associated with significantly increased ORN rates (P < 0.05 for each).

CONCLUSION

Low pre-CCRT Hb levels appeared to be independently linked to significantly higher ORN rates. Pretreatment Hb levels may be used to establish preventive measures and predict ORN.

To extract or not extract teeth prior to head and neck radiotherapy? A systematic review and meta-analysis

PURPOSE

Teeth with poor prognosis are generally recommended to be extracted prior to head and neck radiotherapy (RT) to reduce the risk of developing osteoradionecrosis (ORN), although controversies have been reported. The present systematic review aimed to determine whether tooth extraction prior to head and neck RT may be associated with a reduced risk of developing ORN compared to dental extraction during or after RT.

METHODS

The review protocol was registered in PROSPERO (CRD42021241631). The review was reported according to the PRISMA checklist and involved a comprehensive search of PubMed, Scopus, Embase, Cochrane Library, LILACS, and Web of Science, in addition to the gray literature. The selection of studies was performed in two phases by two reviewers independently. The risk of bias of individual studies was analyzed using the Joanna Briggs Institute checklist for cross-sectional studies, and the certainty of evidence was assessed using the GRADE tool.

RESULTS

Twenty-eight observational studies were included in the qualitative synthesis, which showed substantial heterogeneity regarding the association between the timing of tooth extraction and ORN development. Twenty-seven of 28 studies were pooled in a meta-analysis that demonstrated a significant association between an increased risk of ORN and post-RT tooth extraction (odds ratio: 1.98; 95% CI: 1.17-3.35; p = 0.01).

CONCLUSION

It was confirmed with moderate certainty that dental extractions should be performed prior to the start of head and neck RT to reduce the risk of ORN.

Computed Tomography Radiomics Kinetics as Early Imaging Correlates of Osteoradionecrosis in Oropharyngeal Cancer Patients

Osteoradionecrosis (ORN) is a major side-effect of radiation therapy in oropharyngeal cancer (OPC) patients. In this study, we demonstrate that early prediction of ORN is possible by analyzing the temporal evolution of mandibular subvolumes receiving radiation. For our analysis, we use computed tomography (CT) scans from 21 OPC patients treated with Intensity Modulated Radiation Therapy (IMRT) with subsequent radiographically-proven ≥ grade II ORN, at three different time points: pre-IMRT, 2-months, and 6-months post-IMRT. For each patient, radiomic features were extracted from a mandibular subvolume that developed ORN and a control subvolume that received the same dose but did not develop ORN. We used a Multivariate Functional Principal Component Analysis (MFPCA) approach to characterize the temporal trajectories of these features. The proposed MFPCA model performs the best at classifying ORN vs. Control subvolumes with an area under curve (AUC) = 0.74 [95% confidence interval (C.I.): 0.61–0.90], significantly outperforming existing approaches such as a pre-IMRT features model or a delta model based on changes at intermediate time points, i.e., at 2- and 6-month follow-up. This suggests that temporal trajectories of radiomics features derived from sequential pre- and post-RT CT scans can provide markers that are correlates of RT-induced mandibular injury, and consequently aid in earlier management of ORN.

Hospital Dentistry: The Swiss-Army Knife of Dental Medicine

Hospital Dentistry is an inclusive synergism of the recognized dental specialties in an emergency/hospital atmosphere. This perspective composition serves to display the breadth of Hospital Dentistry from an observational and creative viewpoint while elucidating the role of the Hospital Dentist in the dynamic large university hospital setting. It calls for increased awareness of the field of Hospital Dentistry and the potential for its specialized role in the future of dental medicine. Hospital-based General Practice Residencies (GPR) expose trainees to Hospital Dentistry and its integrated role in medicine. Exploring the ventures of Hospital Dentistry highlight the need to increase Hospital Dentistry-focused student groups while encouraging advanced dental education through GPR programs. The rising geriatric community, complex patient caseload, and population growth call for the need to expand the field of Hospital Dentistry through its recognition as a specialty in the future of dental medicine.

Timing of dental extractions in patients undergoing radiotherapy and the incidence of osteoradionecrosis: a systematic review and meta-analysis

This systematic review aimed to examine whether the incidence of osteonecrosis differed between patients who have dental extractions before or after radiotherapy (RT). The reported incidence of osteoradionecrosis (ORN) of the jaws following RT to the head and neck varies widely in the literature. Currently, for patients with head and neck cancer there are no universally accepted guidelines on the optimal timing of dental surgery relative to RT to minimise incident ORN. A literature review was conducted using the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) criteria. A search of PubMed, EMBASE, Evidence-Based Medicine, and Web of Science databases targeted literature published up to and including 10 April 2020. Two independent reviewers assessed studies for eligibility against inclusion criteria. An assessment of bias was conducted for each of the included studies and relevant data extracted. A meta-analysis was undertaken using the statistical methods described. Twenty-four of 708 studies were included. They were heterogeneous and included a wide variation of RT methods, head and neck malignancies, and comorbidities. While some concluded that the incidence of ORN was dependent on the timing of dental extractions in relation to RT, with regard to the risk of its development, others reported additional factors such as age, comorbidities, extent of surgical resection, and dose and field of radiation, as more important predictors than timing. In many there was consistent lack of detail around the timing of dental procedures in relation to the delivery of RT. From 21 studies including 36,294 patients, of whom 14,389 had extractions before RT, the pooled incidence of ORN was 5.5% (95% CI: 2.1% to 10.1%). Significant heterogeneity was found in Cochran's Q-test (p<0.001) and Higgins I²=98.0%. From 21 studies including 37,805 patients, of whom 6030 had extractions after RT, the pooled incidence of ORN was 5.3% (95% CI: 2.9% to 8.2%). Significant heterogeneity was found in Cochran's Q-test (p<0.001) and Higgins I²=80.0%. There was no statistically significant difference between these two groups (random-effects model Q=0.12, p=0.73). Large, longitudinal studies with a priori-specified methods are needed to identify, recruit, and prospectively follow patients with head and neck cancer for the onset of ORN after dental surgery. This will allow clinical guidelines to be established to assist clinicians to plan treatment when extractions are indicated in patients undergoing RT to the head and neck.

Preradiation tooth extraction and jaw osteoradionecrosis: Nationwide population-based retrospective study in Taiwan

OBJECTIVE

Radiotherapy (RT) for head and neck cancer (HNC) within 7 days of tooth extraction is contraindicated because it may increase the risk of osteoradionecrosis of the jaw (ORNJ). However, delayed RT could compromise survival in patients with HNC. By using a national healthcare database, we reviewed the contraindications and analysed other risk factors for ORNJ.

DESIGN

A retrospective cohort study.

SETTING

By using Taiwan's National Health Insurance Research Database, 5,062 HNC patients with at least one tooth extraction 1-21 days before the first RT day (index day) and without any extractions during or after RT from 2000 to 2013 were included. The patients were divided into two groups according to the time of tooth extraction before the index day: 1-7 days and 8-21 days.

PARTICIPANTS

Taiwanese patients with head and neck cancer.

MAIN OUTCOMES MEASURE

Univariate and multivariate Cox proportional hazard regression models were used to evaluate the risk factors of ORNJ.

RESULTS

The overall incidence of ORNJ in the included patients was 1.03% (mean follow-up duration, 4.07 ± 3.01 years; range, 1.00-13.99 years). Tooth extraction within 7 days before RT was not associated with increased ORNJ risk (hazard ratio [HR] =0.734; P = .312). Significant risk factors for ORNJ included oral cancer (adjusted HR = 3.961), tumour excision surgery within 3 months before RT (adjusted HR = 3.488) and mandibulectomy within 3 months before RT (adjusted HR = 5.985; all P < .001).

CONCLUSION

In a mean follow-up of 4 years, tooth extraction within 7 days before RT for HNC treatment did not increase the ORNJ risk compared with tooth extraction 7-21 days before RT.

Photobiomodulation for mucosal repair in patients submitted to dental extraction after head and neck radiation therapy: a double-blind randomized pilot study

OBJECTIVE

The aim of this study was to evaluate the efficacy of photobiomodulation therapy (PBMT) on the mucosal healing of patients submitted to simple dental extractions after head and neck radiation therapy (HNRT).

METHODS

Forty surgical procedures were randomly assigned into two groups: G1: dental extraction + PBMT (n = 19) and G2: dental extraction + sham-PBMT (n = 21). All patients received antibiotic therapy and the surgical alveolotomy to promote primary closure of the surgical site. Group 1 was submitted to PMBT according to the following parameters: 808 nm, 40 mW, 100 J/cm², 70 s, 2.8 J/point, 14 J/session, and area of 0.028cm². The primary outcome was complete mucosal lining at 14 days, and the secondary outcomes were the presence of infection, postoperative pain, and analgesics intake at 7 days. The patients were evaluated every 7 days until 28 days.

RESULTS

Alveolar mucosal lining was faster in G1, and at 14 postoperative days, 94.7% patients evolved with complete alveolar mucosal lining compared to no patient from G2 (p < 0.001). Patients from G1 reported postoperative pain less frequently (G1 = 4, 21.1% × G2 = 14, 66.7%, p = 0.005), and also reported lower intake of analgesic pills at D7 (21.1% × 66.7%, p = 0.005%). PBMT had a significant positive impact on both postoperative pain (NNT = 2.192, CI95% = 1.372-5.445) and mucosal healing (NNT = 1.056, CI95% = 0.954-1.181).

CONCLUSIONS

This preliminary study strongly supports the use of PMBT to promote surgical alveolar mucosal lining in a shorter time and with less postoperative pain.

Tooth extraction before radiotherapy is a risk factor for developing osteoradionecrosis of the jaws: A systematic review

OBJECTIVES

The aim of this systematic review was to estimate the osteoradionecrosis rate in patients with head and neck cancer due to teeth extraction performed before radiotherapy and to identify possible risk factors.

MATERIAL AND METHODS

PRISMA protocol was used to evaluate and present the results. PubMed, Scopus and Web of Science were used as search engines: English full-length papers of clinical studies, in peer-reviewed journals, were investigated. Cumulative meta-analysis was performed with a random effects model (PROSPERO registration code: CRD42018079986).

RESULTS

Among 2,020 records screened, 8 were included in this review. Sixteen of 494 patients who underwent tooth extraction before radiotherapy developed osteoradionecrosis, with an osteoradionecrosis incidence of 2.2% (95% Confidence of Interval = 0.6-3.9, p < .185, I²  = 3,044%). All cases were reported in the mandible. No other clinical risk factor for osteoradionecrosis was detected.

CONCLUSIONS

Even if it is generally recommended to remove oral foci before radiotherapy, this systematic review confirmed that teeth extractions before radiotherapy represent a risk factor for osteoradionecrosis; the considerable amount of missing data prevented us from identifying other possible risk factors for osteoradionecrosis onset. Major efforts should be done to perform sounder methodological clinical investigations.

Risk assessment for osteoradionecrosis of the jaws in patients with head and neck cancer

Objectives

To identify the potential risk factors for the occurrence of osteoradionecrosis (ORN) of the jaws among patients who have been treated with radiotherapy for head and neck malignancy.

Methods

The study comprised of 231 patients treated with radiotherapy for head and neck malignancy at a tertiary referral center. The following details were recorded for each patient: age, gender, histopathological diagnosis, clinical staging, tumor site, treatment modality, radiation dose, radiation field, number of fractions, type of accelerator used, radiation area and duration of follow-up. Patient’s tobacco, alcohol habit history, and history of extraction of teeth before/during/after radiotherapy were also noted.

Results

Thirteen patients had osteoradionecrosis (frequency 5.62%). Among the radiotherapy variables assessed, increased radiation area was found to be significantly associated with the occurrence of osteoradionecrosis. Among the 13 ORN cases, 10 (76.9%) had a history of tobacco consumption, 8 (61.5%) had a time interval between radiotherapy and occurrence of ORN of less than 1-year duration.

Conclusions

We found a low cumulative incidence of osteoradionecrosis and a tendency to occur within a year of starting radiotherapy. Patients of older age, those with a prior tobacco habit may be considered more liable to develop osteoradionecrosis. A larger radiation field may also put patients at hazard for developing osteoradionecrosis.

Pre-irradiation dental care: Ready-to-use templates for oropharyngeal cancers

Aim

To develop a tool in order to guide pre-irradiation dental care (PIDC) for patients with oropharyngeal cancers.

Background

Osteoradionecrosis of the jaws is a potential complication of radiotherapy (RT) for head and neck cancers. To prevent this complication, PIDC can involve multiple dental extractions as a preventative measure to avoid post-RT complications. However, there is no standardized tool to guide PIDC.

Materials and methods

From January 2005 to October 2015, 120 head and neck cancer patients were prospectively included in a study investigating dysgeusia after RT. From this cohort, patients were enrolled according to the following inclusion criteria: histopathological confirmation of oropharyngeal squamous cell carcinoma; stage T1-4 N1-3 M0; ≤10 missing teeth. Individual teeth were retrospectively delineated on planning computed tomography and doses to dentition were assessed to generate templates.

Results

Thirty-three patients were included. Molars received highest doses with a mean dose of 50 Gy (range; 19-75 Gy). Ipsi-lateral and contralateral wisdom teeth received RT dose superior to 50 Gy in 92% and 56% of cases, respectively. Patients with advanced disease (T4 or N2c-3) received higher mean doses on inferior and ipsi-lateral dental arches compared to other patients (T1-3 N0-2b): 42 Gy vs. 39 Gy and 44 Gy vs. 39 Gy (p < 0.05), respectively.

Conclusion

Pre-RT dose distribution templates are an objective way to prepare PIDC. Further studies with a larger cohort are needed to validate these templates.

Osteoradionecrosis of the jaws: definition, epidemiology, staging and clinical and radiological findings. A concise review

Osteoradionecrosis (ORN) of the jaws is a pernicious complication of radiation therapy for head and neck tumours. This article aims to provide an update on data related to the definition, epidemiology, staging, and clinical and radiological findings of ORN of the jaws. Using certain keywords, an electronic search was conducted spanning the period from January 1922 to April 2014 to identify the available related investigations. Pooled data were then analysed. ORN is described as exposed irradiated bone that fails to heal over a period of 3 months without evidence of persisting or recurrent tumour. The prevalence of ORN varies in the literature. Several staging or scoring systems of ORN have been proposed. Clinical findings include ulceration or necrosis of the mucosa with exposure of necrotic bone. Radiological findings are not evident in the early stages of ORN. Furthermore ORN may not be apparent in imaging even when the disease is advanced. Taking into account the severity of ORN and the difficulties in diagnosing it early and accurately, the clinician should be aware of this complex entity in order to prevent its appearance or the development of more severe complications.

Dental status, dental treatment procedures and radiotherapy as risk factors for infected osteoradionecrosis (IORN) in patients with oral cancer - a comparison of two 10 years' observation periods

Objectives

Dental status, dental treatment procedures and radiotherapy dosage as potential risk factors for an infected osteoradionecrosis (IORN) in patients with oral cancers: Retrospective evaluation of 204 patients treated in two observation periods of approximately ten years each.

Patients and methods

In group A, 90 patients were treated in the years 1993-2003, in group B 114 patients in the years 1983-1992 (data in brackets). All patients had histopathologically proven squamous cell cancers, mainly UICC stages III and IV. 70% (85%, n.s.) had undergone surgery before radiotherapy. All patients were referred to the oral and maxillofacial surgeon for dental rehabilitation before further treatment.

Radiotherapy was performed using a 3D-conformal technique with 4-6MV photons of a linear accelerator (Co-60 device up to 1987). The majority of patients were treated using conventional fractionation with total doses of 60-70 Gy in daily fractions of 2 Gy. Additionally, in group A, hyperfractionation was used applying a total dose of 72 Gy in fractions of 1.2 Gy twice daily (time interval > 6 hours). In group B, a similar schedule was used up to a total dose of 82.8 Gy (time interval 4-6 hours). 14 (0) patients had radiochemotherapy simultaneously. After therapy, the patients were seen regularly by the radiooncologist and – if necessary – by the oral and maxillofacial surgeon. The duration of follow-up was 3.64 years (5 years, p = 0.004).

Results

Before radiotherapy, the dental health status was very poor. On average, 21.5 (21.2, n.s.) teeth were missing. Further 2.04 teeth (2.33, n.s.) were carious, 1.4 (0.3, p = 0.002) destroyed.

Extractions were necessary in 3.6 teeth (5.8, p = 0.008), conserving treatment in 0.4 (0.1, p = 0.008) teeth. After dental treatment, 6.30 (4.8, n.s.) teeth remained.

IORN was diagnosed after conventionally fractionated radiotherapy in 15% (11%, n.s.), after hyperfractionation in 0% (34%, p = 0.01).

Conclusion

Within more than 20 years there was no improvement in dental status of oral cancer patients. Extensive dental treatment procedures remained necessary. There was an impressive reduction of the IORN frequency in patients treated in a hyperfractionated manner probably resulting from a dose reduction and an extension of the interfraction time.

Dental status, dental rehabilitation procedures, demographic and oncological data as potential risk factors for infected osteoradionecrosis of the lower jaw after radiotherapy for oral neoplasms: a retrospective evaluation

Purpose

Retrospective evaluation of the dental status of patients with oral cancer before radiotherapy, the extent of dental rehabilitation procedures, demographic and radiotherapy data as potential risk factors for development of infected osteoradionecrosis of the lower jaw.

Methods

A total of 90 patients who had undergone radiotherapy for oral cancer were included into this retrospective evaluation. None of them had distant metastases. After tumour surgery the patients were referred to an oral and maxillofacial surgeon for dental examination and the necessary dental rehabilitation procedures inclusive potential tooth extraction combined with primary soft tissue closure. Adjuvant radiotherapy was started after complete healing of the gingiva (> 7 days after potential extraction). The majority of patients (n = 74) was treated with conventionally fractionated radiotherapy with total doses ranging from 50-70Gy whereas further 16 patients received hyperfractionated radiotherapy up to 72Gy. The records of the clinical data were reviewed. Furthermore, questionnaires were mailed to the patients’ general practitioners and dentists in order to get more data concerning tumour status and osteoradionecrosis during follow-up.

Results

The patients’ dental status before radiotherapy was generally poor. On average 10 teeth were present, six of them were regarded to remain conservable. Extensive dental rehabilitation procedures included a mean of 3.7 tooth extractions. Chronic periodontitis with severe attachment loss was found in 40%, dental biofilm in 56%. An infected osteoradionecrosis (IORN) grade II according to (Schwartz et al., Am J Clin Oncol 25:168-171, 2002) was diagnosed in 11 of the 90 patients (12%), mostly within the first 4 years after radiotherapy. We could not find significant prognostic factors for the occurrence of IORN, but a trendwise correlation with impaired dental status, rehabilitation procedures, fraction size and tumour outcome.

Conclusion

The occurrence of IORN is an important long-term side effect of radiotherapy for oral cancers. From this data we only can conclude that a poor dental status, conventional fractionation and local tumour progression may enhance the risk of IORN which is in concordance with the literature.

Dental extractions prior to radiotherapy to the jaws for reducing post-radiotherapy dental complications

BACKGROUND

Radiotherapy as part of head and neck cancer treatment leaves patients requiring much dental rehabilitation in a compromised environment that is difficult for the patient and the dental team to manage.

OBJECTIVES

To assess the effects of maintaining the patient's natural dentition during radiotherapy in comparison to extracting teeth before radiotherapy in areas that are difficult to access by the patient and the dentist, should reduction in mouth opening occur after radiotherapy to the jaws.

SEARCH METHODS

We searched the Cochrane Oral Health Group's Trials Register (to 22 November 2012), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2012, Issue 11), MEDLINE via OVID (1946 to 22 November 2012), EMBASE via OVID (1980 to 22 November 2012), CANCERLIT via PubMed (1950 to 22 November 2012), CINAHL via EBSCO (1980 to 22 November 2012) and reference lists of articles. We advertised for currently ongoing studies via the Cochrane Oral Health Group website and the Cochrane Oral Health Group Twitter feed. 

SELECTION CRITERIA

Randomised controlled trials comparing extraction of teeth prior to radiotherapy with leaving teeth in situ during radiotherapy to the jaws.

DATA COLLECTION AND ANALYSIS

Three review authors independently assessed the results of the searches for inclusion in the review. 

MAIN RESULTS

No randomised controlled trials were found.

AUTHORS' CONCLUSIONS

There are no randomised controlled trials to assess the effect of extracting teeth prior to radiotherapy compared to leaving teeth in the mouth during radiotherapy to the jaws.

Superimposed infection in mandibular osteoradionecrosis: diagnosis and outcomes

BACKGROUND

Radiation therapy can result in osteoradionecrosis (ORN) and mucosal ulceration predisposing to infection.

METHODS

Fourteen patients presenting with infectious sequelae related to mandibular ORN were retrospectively reviewed.

RESULTS

In most patients, infection followed diagnosis of ORN; but in 4 patients, ORN was not diagnosed until after the time of infection and imaging. An early imaging finding of ORN was lingual cortical defects near the last molar. Pain followed by erythema, purulent drainage, and subperiosteal abscess by imaging were the most common signs of infection. In most patients, conservative management eventually failed and segmental mandibulectomies were required.

CONCLUSIONS

Soft tissue infection with characteristic bone findings such as subperiosteal abscess and cortical bone erosions helps to distinguish infected ORN from recurrent tumor or sterile ORN. In patients previously treated with radiation who present with infection, pain or an avid PET scan with bone involvement, the mandible should be scrutinized.

Osteoradionecrosis of the jaws--a current overview--Part 2: dental management and therapeutic options for treatment

PURPOSE

The aim of this paper is to explore the current theories about pretreatment assessment and dental management of patients receiving head and neck radiotherapy, and the therapeutic options to treat osteoradionecrosis of the jaws, based on the literature review.

DISCUSSION

Osteoradionecrosis is one of the most serious oral complications of head and neck cancer treatment. Osteoradionecrosis is a severe delayed radiation-induced injury, characterized by bone tissue necrosis and failure to heal. Osteoradionecrosis either stabilizes or gradually worsens and is notoriously difficult to manage. Because most cases occur in patients who were dentulous in the mandible at tumor onset, proper dental management is the single most important factor in prevention.

CONCLUSIONS

Complete dental clearance before treatment is no longer necessary. Controversy exists regarding the management of osteoradionecrosis of the maxillofacial skeleton because of the variability of this condition. The treatment of osteoradionecrosis has included local wound care, antibiotic therapy, surgical procedures, and the administration of hyperbaric oxygenation. Recently, new methods of treatment were introduced, according to the new theory about its pathophysiology.

Osteoradionecrosis of the jaws--a current overview--part 1: Physiopathology and risk and predisposing factors

PURPOSE

The aim of this paper is to explore the current theories about definition, classification, incidence and physiopathology of osteoradionecrosis (ORN) of the jaws. Moreover, it is discussed the predisposing and risk factors for the development of osteoradionecrosis based on the literature review.

DISCUSSION

Osteoradionecrosis is one of the most serious oral complications of head and neck cancer treatment. Osteoradionecrosis is a severe delayed radiation-induced injury, characterised by bone tissue necrosis and failure to heal. Osteoradionecrosis either stabilises or gradually worsens and is notoriously difficult to manage. The most widely accepted theory to explain its cause until recently was the theory of hypoxia, hypovascularity and hypocellularity. A new theory for the pathogenesis of osteoradionecrosis was proposed. The clinical presentations of osteoradionecrosis are pain, drainage and fistulation of the mucosa or skin that is related to exposed bone in an area that has been irradiated. The tumour size and location, radiation dose, local trauma, dental extractions, infection, immune defects and malnutrition can predispose its development.

CONCLUSIONS

A better understanding of risk factors for the development ORN and of the underlying pathophysiology may improve our ability to prevent this complication and help to improve the prognosis for those being treated for osteoradionecrosis.

Dental extractions and radiotherapy in head and neck oncology: review of the literature

Management of irradiated patients with cancer in the head and neck region represents a challenge for multidisciplinary teams. Radiotherapy promotes cellular and vascular decrease that results in a low response rate in the healing. Consequently, surgical procedures in irradiated tissues present high rates of complication. Osteoradionecrosis (ORN) is the most severe sequelae caused by radiotherapy. It is associated with previous extractions especially those carried out post-irradiation. The management of this side effect is difficult and can result in bone or soft tissue loss, affecting the quality of life. The literature regarding dental extractions performed before and after head and neck radiotherapy was evaluated, focusing on indications, criteria, surgical techniques and adjunctive therapies such as antibiotics and hyperbaric oxygen. Osteoradionecrosis can be minimized by oral evaluation and care prior to irradiation and healing time which allows tissue repair until the commencement of radiotherapy. In dental extractions realized after irradiation, minimal trauma, alveolectomy, primary alveolar closure and adjunctive therapies are recommended. Patients must be evaluated before radiation therapy and at that time all unrestorable teeth and/or teeth with periodontal problems must be extracted to reduce the post-radiotherapy exodontias that contribute to ORN. Once dental extractions become unavoidable after irradiation, additional care is needed.

Osteonecrosis of the jaws and bisphosphonate treatment in cancer patients

PURPOSE

Osteonecrosis of the jaws is described as an intraoral complication after administration of intravenous nitrogen-containing bisphosphonates. In a retrospective study, patients with osteonecrosis of the jaws after bisphosphonate treatment were evaluated with regard to diagnostic investigations and therapeutic management.

PATIENTS AND METHODS

Seventeen patients with osteonecrosis of the jaws after bisphosphonate treatment who were referred to our department between July 2004 and June 2005 were included in this study. Computer tomography, magnetic resonance imaging, scintigraphy, bacteriology and biopsy were used in diagnostic evaluation. All patients were treated surgically.

RESULTS

The reasons for bisphosphonate treatment were multiple myeloma in 12 patients, breast cancer with bone metastasis in four patients and histiocytosis X in one patient. Five patients had received intravenous pamidronate and 12 patients zoledronic acid. The median number of treatment cycles for pamidronate was 36 times (range 4-100) in 38 months (range 4-100). Zolendric acid was given 23.5 times (range 5-39) in 26 months (range 5-39). Nine patients had a lesion in the mandible, eight in the maxilla. Clinical symptoms were exposed bone, pain and local inflammation of the mucosa. Computer tomography showed sclerotic areas in the osteonecrosis zone. The biopsy did not show a metastatic lesion. Sequestrectomy and decortication was adequate in the follow-up.

CONCLUSION

Nitrogen-containing bisphosphonates appear to be associated with the risk of developing osteonecrosis of the jaws. To reduce this risk, patients should be evaluated by a dentist before beginning treatment with intravenous bisphosphonates.

Osteoradionecrosis prevention myths

PURPOSE

To critically analyze controversial osteoradionecrosis (ORN) prevention techniques, including preradiation extractions of healthy or restorable teeth and the use of prophylactic antibiotics or hyperbaric oxygen (HBO) treatments for preradiation and postradiation extractions.

METHODS

The author reviewed ORN studies found on PubMed and in other article references, including studies on overall ORN incidence and pre- and postradiation incidence, with and without prophylactic HBO or antibiotics.

RESULTS

Owing in part to more efficient radiation techniques, the incidence of ORN has been declining in radiation patients over the last 2 decades, but the prevention of ORN remains controversial. A review of the available literature does not support the preradiation extraction of restorable or healthy teeth. There is also insufficient evidence to support the use of prophylactic HBO treatments or prophylactic antibiotics before extractions or other oral surgical procedures in radiation patients.

CONCLUSIONS

To prevent ORN, irradiated dental patients should maintain a high level of oral health. A preradiation referral for a dental evaluation and close collaboration by a multidisciplinary team can be invaluable for radiation patients. As with most other dental patients, restorable and healthy teeth should be retained in irradiated patients. The use of prophylactic HBO or antibiotics should be reconsidered for preradiation and postradiation extractions.

Osteonecrosis of the jaw in cancer after treatment with bisphosphonates: incidence and risk factors

PURPOSE

Osteonecrosis of the jaw (ONJ) has been associated recently with the use of pamidronate and zoledronic acid. We studied the incidence, characteristics, and risk factors for the development of ONJ among patients treated with bisphosphonates for bone metastases.

PATIENTS AND METHODS

ONJ was assessed prospectively since July 2003. The first bisphosphonate treatment among patients with ONJ was administered in 1997. Two hundred fifty-two patients who received bisphosphonates since January 1997 were included in this analysis.

RESULTS

Seventeen patients (6.7%) developed ONJ: 11 of 111 (9.9%) with multiple myeloma, two of 70 (2.9%) with breast cancer, three of 46 (6.5%) with prostate cancer, and one of 25 (4%) with other neoplasms (P = .289). The median number of treatment cycles and time of exposure to bisphosphonates were 35 infusions and 39.3 months for patients with ONJ compared with 15 infusions (P < .001) and 19 months (P = .001), respectively, for patients with no ONJ. The incidence of ONJ increased with time to exposure from 1.5% among patients treated for 4 to 12 months to 7.7% for treatment of 37 to 48 months. The cumulative hazard was significantly higher with zoledronic acid compared with pamidronate alone or pamidronate and zoledronic acid sequentially (P < .001). All but two patients with ONJ had a history of dental procedures within the last year or use of dentures.

CONCLUSION

The use of bisphosphonates seems to be associated with the development of ONJ. Length of exposure seems to be the most important risk factor for this complication. The type of bisphosphonate may play a role and previous dental procedures may be a precipitating factor.

French multicenter phase III randomized study testing concurrent twice-a-day radiotherapy and cisplatin/5-fluorouracil chemotherapy (BiRCF) in unresectable pharyngeal carcinoma: Results at 2 years (FNCLCC-GORTEC)

BACKGROUND

Unresectable carcinomas of the oropharynx and hypopharynx still have a poor long-term prognosis. Following a previous phase II study, this phase III multicenter trial was conducted between November 1997 and March 2002.

METHODS

Nontreated, strictly unresectable cases were eligible. Twice-daily radiation: two fractions of 1.2 Gy/day, 5 days per week, with no split (D1-->D46). Total tumor doses: 80.4 Gy/46 day (oropharynx), 75.6 Gy/44 day (hypopharynx). Chemotherapy (arm B): Cisplatin 100 mg/m2 (D1, D22, D43); 5FU, continuous infusion (D1-->D5), 750 mg/m2/day cycle 1; 430 mg/m2/day cycles 2 and 3.

RESULTS

A total of 163 evaluable patients. Grade 3-4 acute mucositis 82.6% arm B/69.5% arm A (NS); Grade 3-4 neutropenia 33.3% arm B/2.4% arm A (p < 0.05). Enteral nutrition through gastrostomy tube was more frequent in arm B before treatment and at 6 months (p < 0.01). At 24 months, overall survival (OS), disease-free survival (DFS), and specific survival (SS) were significantly better in arm B. OS: 37.8% arm B vs. 20.1% arm A (p = 0.038); DFS: 48.2% vs. 25.2% (p = 0.002); SS: 44.5% vs. 30.2% (p = 0.021). No significant difference between the two arms in the amount of side effects at 1 and 2 years.

CONCLUSION

For these unresectable cases, chemoradiation provides better outcome than radiation alone, even with an "aggressive" dose-intensity radiotherapy schedule.

Osteoradionecrosis of the mandible

PURPOSE OF REVIEW

Osteoradionecrosis of the mandible is a serious complication of radiation therapy to the head and neck. Given the increased use of radiation therapy and combined chemotherapy-radiation therapy regimens in treatment of head and neck malignancies, it is anticipated that osteoradionecrosis will continue to be an important clinical problem. Recently, new concepts have been introduced regarding the pathogenesis of osteoradionecrosis, and these ideas help outline new guidelines for treatment.

RECENT FINDINGS

Current literature focuses on the probability of a fibroatrophic mechanism for the development of osteoradionecrosis, rather than the traditional vascular insufficiency mechanism. Because of the evolution of this new idea, as well as a double-blinded, placebo-controlled study finding no benefit from the use of hyperbaric oxygen for advanced osteoradionecrosis of the mandible, new treatment considerations have emerged. Ongoing research is also being conducted to clarify the role of osteoclasts in the pathogenesis of osteoradionecrosis. Restoration of blood supply or vascularized tissue to the affected area continues to be of primary importance in the resolution of osteoradionecrosis.

SUMMARY

It is clear that the cause and pathogenesis of osteoradionecrosis are far more complex than originally believed. Current and future research on this multifaceted topic will focus on the cellular basis of this condition, because as it is elucidated, more effective medical treatment regimens will become evident.

Bisphosphonate Osteochemonecrosis (Bis-Phossy Jaw): Is This Phossy Jaw of the 21st Century?

PURPOSE

Bisphosphonates are being implicated in a growing number of complications of the jaws. A number of terms are being applied to this phenomenon and perhaps the descriptive term bisphosphonate osteochemonecrosis has the most merit. But the eerie similarity of this 21st century disease process with the 19th century disease known as phossy jaw is striking. As the nomenclature continues to evolve, the term used in this article will be bis-phossy jaw. This article will explore historical and current aspects of these diseases. Although there may be other mitigating factors, such as oral health, chemotherapy history, immune status, Karnofsky performance status, or Kaplan-Feinstein index, bisphosphonates appear to be the necessary component in cases of bis-phossy jaw.

MATERIALS

This is primarily a review article on reported cases of bis-phossy jaw, with historical looks at phossy jaw and osteoradionecrosis. Our laboratory has reviewed 20 suspected cases of bis-phossy jaw and the typical histopathologic features of bis-phossy jaw are presented.

RESULTS

Descriptions of phossy jaw and current bis-phossy jaw cases are remarkably similar. Histopathologic features of bis-phossy jaw showed intact vascular channels, even in areas with acute inflammatory infiltrates and bacterial overgrowth. Non-vital bone fragments with reduced evidence of osteoclastic action were also noted.

CONCLUSION

Bis-phossy jaw may have more of a bacterial cofactor risk than osteoradionecrosis, and though altered angiogenesis may yet prove to be a factor, avascularity does not appear to be a major cofactor. The historical disease phossy jaw appears to serve as a possible analogous disease for current research and treatment of bis-phossy jaw. Prevention and early identification of patients at risk should be of prime concern.

Implications of radiation dosimetry of the mandible in patients with carcinomas of the oral cavity and nasopharynx treated with intensity modulated radiation therapy

Intensity modulated radiation therapy (IMRT) is a newer method of delivering highly conformal, salivary gland sparing radiation treatment that is finding increasing applications in head and neck malignancies. However, the radiation dose distribution to the mandible is rarely considered with IMRT, and the potential risks of osteoradionecrosis or osseointegrated implant failure are not well characterized for this modality. In a series of 10 patients with oral cavity and nasopharyngeal cancers who previously underwent IMRT, examination of the three-dimensional mandibular dose distribution was undertaken. The findings indicate a modest potential risk of osteoradionecrosis and osseointegrated implant failure in cases where IMRT optimization constraints are not specifically aimed at sparing the mandibular bone. Significantly higher mandibular doses (P < 0.04) were received in cases of oral cavity as opposed to nasopharyngeal cancers with IMRT. Efforts to optimize IMRT to further reduce doses to the mandible should be considered, and development of software tools to integrate three-dimensional dose distributions into planning of post-radiotherapy osseointegration would be beneficial.