Incidence and prevention of osteoradionecrosis after dental extraction in irradiated patients: a systematic review

Current trends and available evidence on low-level laser therapy for osteoradionecrosis: A scoping review

BACKGROUND

This scoping review explored current trends and available evidence in Low-Level Laser Therapy (LLLT) in the treatment and prevention of osteoradionecrosis.

METHODS

The search strategy was conducted in MEDLINE/PubMed, EMBASE, Web of Science, and grey literature on January 15, 2024, without language or time restrictions.

RESULTS

19 studies were included. The application of LLLT protocols was 58% for therapeutic use, 21% for preventive use, and 21% for a combination of both. Regarding the use of antimicrobial photodynamic therapy (aPDT), 41% of the studies employed this technique, which utilized methylene blue as the photosensitizer. For treatments associated with photobiomodulation, 57% reported pharmacological treatment, 29% surgical treatment, 11% prescribed chlorhexidine mouthwashes, and 4% other therapies. In vivo studies used diode lasers emitting low incident power densities in the near-infrared wavelength (67%) at 780 to 904 nm. In comparison, case reports also used diode lasers emitting low incident power densities in the red and near-infrared wavelength (64%) at 660 to 904 nm. The continuous emission mode was utilized in 83% of in vivo studies and 17% of the case reports. None of the studies included in this review reported all laser parameters.

CONCLUSIONS

In general, studies suggested that LLLT can be used for therapeutic and preventive applications in the management of osteoradionecrosis. However, clinical studies are case reports and the variability in laser parameters across the included studies poses challenges for establishing standardized treatment protocols. The lack of comprehensive data on laser parameters underscores the need for future research to focus on standardizing LLLT protocols and conducting well-designed, large-scale clinical trials. This approach will help to better evaluate the effectiveness of LLLT and potentially integrate it more reliably into clinical practice.

Are prophylactic antibiotics effective in preventing osteoradionecrosis after high-risk dental extractions?

STUDY DESIGN

A systematic review and meta-analysis.

OBJECTIVE

To assess and compare the effectiveness of different adjunctive treatments during tooth extraction in post-radiotherapy head and neck patients for preventing osteoradionecrosis (ORN).

PATIENTS AND METHODS

Two independent reviewers conducted an electronic search through PubMed, Embase, Cochrane Libraries, Scopus and Web of Science databases using relevant search terms. Additionally, references of relevant articles were manually searched for eligible studies. Included were full-length articles (randomized controlled trials (RCTs), clinical trials, or observational studies) published in English, reporting on ORN occurrence after dental extraction, with or without adjunctive interventions, in patients who had previous radiotherapy. Data extraction was similarly performed by two independent researchers. For quality assessment, bias in observational studies was evaluated using the ROBINS-I tool, while the RoB 2 tool was used for RCTs. One-arm meta-analyses estimated pooled ORN prevalence rates for different adjunctive treatments based on patient-level outcomes. For studies with direct comparisons between two modalities, pooled odds ratios for ORN were calculated using pairwise meta-analyses. This systematic review followed PRISMA guidelines and was registered in the PROSPERO database.

RESULTS

A total of 29 studies with 1520 patients were included, comprising 4 RCTs, 4 prospective studies, and 21 retrospective observational studies. Five adjunctive treatment modalities around the time of dental extractions were identified: hyperbaric oxygen (HBO), pentoxifylline-tocopherol (PENTO), antibiotics (ABX), platelet-rich fibrin and photobiomodulation. Of the 25 observational studies included, 11 had a serious risk of bias, while all RCTs but 1 had low risk of bias. Egger's test showed no publication bias for the HBO and ABX groups (p > 0.05). Antibiotics were used in 17 studies, with significant variations in preoperative and postoperative protocols. Most studies utilized penicillin or clindamycin. The pooled prevalence of ORN was significantly lower in the HBO (4.6%), PENTO (3.4%), and ABX (3.8%) groups compared to the Control (17.6%), as indicated by the non-overlapping 95% CIs between the Control and any of the intervention groups. In studies with direct comparisons, HBO exhibited lower odds of developing ORN than the Control (odds ratio [OR] = 0.27) and ABX (OR = 0.57), although these differences were not statistically significant.

CONCLUSION

HBO, PENTO, and ABX show similar reduction in ORN rates compared to no intervention. Given its cost-effectiveness and accessibility, ABX may be the most practical prophylactic modality at present.

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.

Prevention of osteoradionecrosis in patients with head and neck cancer treated with radiation therapy

BACKGROUND

Osteoradionecrosis is a long-term, serious side effect of head and neck radiation therapy and is associated with significant morbidity and quality of life issues.

METHODS

This paper sought to determine consensus on the prevention and management of osteoradionecrosis by an international panel of multidisciplinary professionals expert in the management of patients with head and neck cancer using a Delphi methodology. Unique to this work is our direct inclusion of the views of patients and carers in our findings.

RESULTS

This study reached consensus on the importance of pre and post oral health assessment and education for patients with head and neck cancer. This was also noted by the patients and carers who took part in the study.

CONCLUSIONS

This work highlights the need for a standardized oral health assessment tool and multidisciplinary care of patients to prevent and manage osteoradionecrosis.

Osteoradionecrosis Rates After Head and Neck Radiation Therapy: Beyond the Numbers

PURPOSE

Osteoradionecrosis (ORN) is a severe late complication of head and neck radiation therapy shown to have profound negative effect on the quality of life of cancer survivors. Over the past few decades, improvements in radiation delivery techniques have resulted in a decrease in the incidence of ORN. However, even with modern radiation therapy techniques, ORN remains an important clinical concern. In recent literature, there is a wide range of reported ORN rates from 0% to as high as 20%. With such a high level of variability in the reported incidence of ORN, oncologists often encounter difficulties estimating the risk of this serious radiation therapy toxicity.

METHODS AND MATERIALS

In this review, the authors present a summary of the factors that contribute to the high level of variability in the reported incidence of ORN.

RESULTS

Variable definition, variable grading, and heterogeneity of both study inclusion criteria and treatment parameters can each significantly influence the reporting of ORN rates.

CONCLUSIONS

Given numerous factors can affect the reported incidence of ORN, a thorough understanding of the clinical context behind the reported ORN rates is needed to comprehend the true risk of this important radiation therapy toxicity.

Impact of outside referral and dental extractions on package time with post-operative radiation therapy for head and neck cancer

INTRODUCTION

Patients with squamous cell carcinoma of the head and neck (HNSCC) often receive post-operative radiotherapy (RT). A package time between surgery and completion of RT of ≤100 days is associated with lower recurrence and longer survival. In this study, we investigate the impact of outside referral and dental extractions on package time, with secondary detriment to relapse-free survival (RFS) and overall survival (OS).

METHODS

We conducted a retrospective chart review on patients with HNSCC who received primary surgical resection at an academic medical centre.

RESULTS

Ninety-four patients met eligibility criteria, 35% experienced recurrence, and 21% died. Median package time was 89.5 days, with 76% of patients achieving a package time ≤100 days. Receiving RT in-house was associated with a shorter package time (P = 0.0004) and higher completion rate within 100 days (P = 0.01). Dental extractions did not affect package time. A Kaplan-Meier analysis was performed to study survival, and a package time ≤100 days was not associated with a change in RFS or OS. A Cox proportional hazard model was used to investigate other factors hypothesized to impact patient survival; none had an effect on RFS, but cancer stage had an effect on OS (P = 0.01).

CONCLUSIONS

We identified that outside referrals, but not dental extractions, prolong treatment package times. We also saw no effect of package time on RFS or OS. These results suggest that patients requesting outside facility referrals for RT may benefit from a streamlined program that expedites the referral process.

Pre-chemoradiotherapy high platelet counts predict jaw osteoradionecrosis in locally advanced nasopharyngeal carcinoma patients

INTRODUCTION

This retrospective study aimed to investigate if pretreatment platelet (PLT) levels can predict the risk of osteoradionecrosis of the jaw (ORNJ) in patients with locally advanced nasopharyngeal carcinoma (LA-NPC) who received concurrent chemoradiotherapy (CCRT).

MATERIAL &METHODS

ORNJ instances were identified from LA-NPC patients' pre- and post-CCRT oral exam records. All pretreatment PLT values were acquired on the first day of CCRT. Receiver operating characteristic curve analysis was used to determine the optimal PLT cutoff that divides patients into two subgroups with distinctive ORNJ rates. The primary outcome measure was the association between pretreatment PLT values and ORNJ incidence rates.

RESULTS

The incidence of ORNJ was 8.8 % among the 240 LA-NPC patients analyzed. The ideal pre-CCRT PLT cutoff which divided the patients into two significantly different ORNJ rate groups was 285,000 cells/µL (PLT ≤ 285,000 cells/µL (N = 175) vs. PLT > 285,000 cells/µL (N = 65)). A comparison of the two PLT groups revealed that the incidence of ORNJ was substantially higher in patients with PLT > 285,000 cells/L than in those with PLT≤285,000 cells/L (26.2% vs. 2.3 %; P < 0.001). The presence of pre-CCRT ≥3 tooth extractions, any post-CCRT tooth extractions, mean mandibular dose ≥ 34.1 Gy, mandibular V57.5 Gy ≥ 34.7 %, and post-CCRT tooth extractions > 9 months after CCRT completion were also associated with significantly increased ORNJ rates. A multivariate Cox regression analysis demonstrated that each characteristic had an independent significance on ORNJ rates after CCRT.

CONCLUSION

An affordable and easily accessible novel biomarker, PLT> 285,000 cells/L, may predict substantially higher ORNJ rates after definitive CCRT in individuals with LA-NPC.

The effects of re-irradiation on the chemical and morphological properties of permanent teeth

This study aimed to assess the in vitro effects of re-irradiation on enamel and dentin properties, simulating head and neck cancer radiotherapy retreatment. Forty-five human permanent molars were classified into five groups: non-irradiated; irradiated 60 Gy, and re-irradiated with doses of 30, 40, and 50 Gy. Raman spectroscopy, scanning electron microscopy (SEM), and energy dispersive x-ray spectroscopy (EDS) were employed for analysis. Raman spectroscopy assessed intensity, spectral area, and specific peaks comparatively. Statistical analysis involved Kolmogorov-Smirnov and One-Way ANOVA tests, with Tukey's post-test (significance level set at 5%). Significant changes in irradiated, non-irradiated, and re-irradiated enamel peaks were observed, including phosphate (438 nm), hydroxyapatite (582 nm), phosphate (960 nm), and carbonate (1070 nm) (p < 0.05). Re-irradiation affected the entire tooth (p > 0.05), leading to interprismatic region degradation, enamel prism destruction, and hydroxyapatite crystal damage. Dentin exhibited tubule obliteration, crack formation, and progressive collagen fiber fragmentation. EDX revealed increased oxygen percentage and decreased phosphorus and calcium post-reirradiation. It is concluded that chemical and morphological changes in irradiated permanent teeth were dose-dependent, exacerbated by re-irradiation, causing substantial damage in enamel and dentin.

Radiation effects in head and neck and role of hyperbaric oxygen therapy: An adjunct to management

Background

Radiotherapy is considered an essential treatment modality in cancers, especially head and neck cancers. Radiotherapy can be given as a definitive, supportive, or adjuvant therapy for various cancers. Radiation damage is an avoidable complication in many patients, after or during radiotherapy. It may be either dose-related, duration-related, or frequency-related. The effects of radiation damage are mainly caused by ischemic necrosis, and once settled it is difficult to manage due to the low vascularity of the affected area.

Aim

To find out the effectiveness of hyperbaric oxygen therapy (HBOT) in the management of radiation damage in the head and neck region.

Materials and Methods

Retrospective data of patients attending the HBOT clinic for postradiotherapy changes were recorded in an Excel sheet and analyzed in this study. Statistical analysis was done.

Result

Our study showed that HBOT is effective in postradiation trismus, xerostomia, discharge, foul smell, discharging sinus, etc., However, it was not found to be significant in the closure of fistula with exposed bone.

Conclusion

HBOT is an effective adjunct modality for the management of postradiation changes in the head and neck region.

An Unknown Foreign laryngeal Object: an exotic complication of skull base osteoradionecrosis

BACKGROUND

Osteoradionecrosis (ORN) of the skull base is a rare complication after head and neck radiation with a broad variety of subsequent complications.

METHODS

A 68-year-old woman with a complex oncological history (right-sided sphenoid meningioma; left-sided neck metastasis of a Cancer of Unknown Primary-CUP) was admitted with a right-sided epi-/ oropharyngeal mass and severe pain exacerbations for further evaluation. CT scan revealed an advanced ORN of the skull base with subsequent abruption of the ventral part of the clivus. This dislocated part of the clivus wedged in the oropharynx for 48 h and then moved towards the larynx, resulting in dyspnea and almost complete airway obstruction.

RESULTS

Due to the dangerous airway situation, an urgent exploration and removal of the dislocated clivus was necessary. After a potential cervical spine instability was ruled out, the patient's airway was initially secured with an awake tracheotomy and the clivus was removed transorally. The tracheostomy tube was removed during the ongoing inpatient stay, and the patient was discharged with significant pain relief.

CONCLUSIONS

The present case illustrates an orphan complication of skull base ORN resulting in a major airway emergency situation.

[Prevention, diagnosis and management of osteoradionecrosis: Where do we stand?]

Osteoradionecrosis (ORN) is a late secondary iatrogenic complication of external radiotherapy for cancers of the upper aero-digestive tract. Despite the systematization of intensity-modulated radiotherapy and its potential for preserving salivary secretion and limiting the dose delivered to the supporting bone, ORN remains a feared and frequent complication. The objective of this literature review was to provide an overview of the management of ORN and to determine the key points that would make it possible to improve patient care. The diagnosis of ORN requires to eliminate tumor recurrence then is based on clinical arguments and imaging by CT or Cone Beam evolving in a chronic mode (more than 3-6 months). The harmonization of its classifications aims to offer comprehensive and multidisciplinary care as early as possible. Primary prevention is based on pre-therapeutic oral and dental preparation, then associated with fluoroprophylaxis if salivary recovery is insufficient and requires supervision of invasive dental care and prosthetic rehabilitation. Semi-automatic contouring tools make it possible to identify doses delivered to dental sectors and guide dental care with personalized dosimetric mapping. Conservative medical treatment is offered at an early stage where innovative medical treatments, highlighted by early studies, could be of interest in the future. In the event of advanced ORN, a non-conservative treatment is then proposed and frequently consists of interruptive mandibulectomy associated with reconstruction by bony free flap, the conditions of implantation remaining to be defined with the support of prospective clinical trials.

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.

Interdisciplinary Collaboration in Head and Neck Cancer Care: Optimizing Oral Health Management for Patients Undergoing Radiation Therapy

Radiation therapy (RT) plays a crucial role in the treatment of head and neck cancers (HNCs). This paper emphasizes the importance of effective communication and collaboration between radiation oncologists and dental specialists in the HNC care pathway. It also provides an overview of the role of RT in HNC treatment and illustrates the interdisciplinary collaboration between these teams to optimize patient care, expedite treatment, and prevent post-treatment oral complications. The methods utilized include a thorough analysis of existing research articles, case reports, and clinical guidelines, with terms such as 'dental management', 'oral oncology', 'head and neck cancer', and 'radiotherapy' included for this review. The findings underscore the significance of the early involvement of dental specialists in the treatment planning phase to assess and prepare patients for RT, including strategies such as prophylactic tooth extraction to mitigate potential oral complications. Furthermore, post-treatment oral health follow-up and management by dental specialists are crucial in minimizing the incidence and severity of RT-induced oral sequelae. In conclusion, these proactive measures help minimize dental and oral complications before, during, and after treatment.

Oral Complications and Management Strategies for Cancer Patients: Principles of Supportive Oncology in Dentistry

PURPOSE OF REVIEW

It is recognized that patients undergoing cancer treatment experience different adverse effects depending on the type of therapy they received. The objective of this work is to provide a scientific evidence-based protocol for oral care in cancer patients. Cancer resection surgery, chemotherapy, and radiotherapy can cause important complications that impact patients' quality of life.

RECENT FINDINGS

Cancer patients, from the moment of diagnosis to the end of treatment and subsequent follow-up, have diverse care needs, both from a systemic and local point of view. The implementation of oral care protocols before, during, and after cancer therapy is essential because it helps to identify risk factors for the development of predictable oral complications. It is essential to establish that all cancer patients, before starting treatment, undergo a systematic dental check-up to avoid limitations during treatment and also alter their quality of life. Regular professional oral care maintenance and follow-up programs are essential to maintaining a patient's long-term oral health.

Prophylactic Use of Pentoxifylline and Tocopherol for Prevention of Osteoradionecrosis of the Jaw after Dental Extraction in Post-Radiated Oral and Oropharyngeal Cancer Patients: An Initial Case Series

Osteoradionecrosis of the jaw is a morbid complication of radiotherapy in patients with oral and oropharyngeal cancers that may be precipitated by dental extractions. Pentoxifylline and tocopherol (PENTO) has been utilized in the management of osteoradionecrosis and as prophylaxis for post-radiated head and neck oncology patients requiring an invasive dental procedure. This observational study aims to report the outcome of the prophylactic use of PENTO in the prevention of osteoradionecrosis of the jaw after dental extractions in post-radiated oral and oropharyngeal cancer patients and to review the current literature on this topic. Four post-radiated oral and oropharyngeal oncology patients were referred to the dental oncology clinic of the University Dental Practice, University of Tennessee Health Sciences Center for dental extractions. All four patients were prescribed pentoxifylline 400 mg BID (twice a day) and tocopherol 400 IU BID (oral tablets) for 2 weeks before extraction(s) and for 6 weeks after extraction(s). All patients were followed up every week after the second week post-extraction if feasible until the extraction site(s) healed (covered by mucosa). The assessment endpoint was defined as 6 weeks post-extraction with the outcomes assessed as using four categories determined by the area of exposed bone: complete healing (complete mucosal coverage of extraction site); partial healing (reduction in size of extraction site); no change; and progression (increase in size of the extraction site). At the assessment endpoint, all patients had complete healing of all extraction sites. The ORN rate at the patient level (0/4) and individual tooth level (0/8) was 0%. All patients tolerated the PENTO medications and no adverse effects from the use of these medications were reported. This limited study in addition to the other reviewed studies estimates the rate of ORN at the patient level as 3.2% (14/436) for post-radiated head and neck oncology patients after dental extractions/invasive oral procedures. In conclusion, this PENTO regimen can reduce/prevent the incidence of ORN in post-radiated head and neck oncology patients. This safe and cost-effective protocol (PENTO regimen) should be further evaluated as prophylaxis for post-radiated head and neck oncology patients requiring an invasive dental procedure. We recommend large prospective studies to be carried out to further validate these findings.

Radiotherapy in the head and neck region influences the chemical and mechanical properties of intraradicular dentin

OBJECTIVES

To investigate the chemical and mechanical properties of intraradicular dentin submitted to radiotherapy.

MATERIALS AND METHODS

Sixteen mandibular incisors were divided into two groups (n = 8): non-irradiated and irradiated. The irradiated teeth were obtained from head and neck radiotherapy patients, with a total dose ranging from 70.2 to 72 Gy divided into 1.8 Gy daily. After sample preparation, intraradicular dentin slices of each root third were evaluated by Raman spectroscopy, energy dispersive spectroscopy and Knoop microhardness test. Data were analyzed by Two-way ANOVA and Tukey's test (α = 0.05).

RESULTS

In Raman spectroscopy, carbonate and amide III showed a significant difference for irradiation and third (carbonate p = 0.021 and p < 0.001; amide III p < 0.001 and p = 0.001, respectively). For amide I, there was a significant difference for third (p < 0.001). For carbonate/mineral ratio, there was a significant difference for irradiation (p = 0.0016) and third (p < 0.001), with the irradiated middle third showing the lowest values. For amide I/amide III ratio, there was a significant difference for irradiation (p = 0.005) in the cervical third. In energy dispersive spectroscopy, carbon (p = 0.004; p = 0.020), phosphorus (p < 0.001; p = 0.009) and calcium (p = 0.008; p = 0.007) showed differences for irradiation and third, with the irradiated groups presenting lower values in cervical and middle thirds. For calcium/phosphorus ratio, there was a significant difference for irradiation (p < 0.001) in cervical and middle thirds. Regarding microhardness, there was a significant difference for irradiation (p < 0.001), with all irradiated groups showing lower microhardness values.

CONCLUSIONS

The radiotherapy altered the chemical and mechanical properties of intraradicular dentin, mainly in the cervical and middle root thirds.

Hyperbaric oxygen therapy as an adjunct treatment of periodontitis, MRONJ, and ONJ: a systematic literature review

OBJECTIVE

To review the available prospective literature on hyperbaric oxygen (HBO) therapy for periodontal conditions.

MATERIALS AND METHODS

A comprehensive electronic and manual search was performed to identify clinical studies on adult patients who underwent hyperbaric oxygen therapy for periodontal treatments. A systematic literature search was conducted in PubMed, Cochrane, and Dentistry Oral Sciences Source databases.

RESULTS

Fourteen articles were included in the final literature review, of which five were RCTs and 11 were prospective clinical studies. Four studies discussed HBO as an adjunct to nonsurgical treatment of periodontitis, eight reported on HBO and osteoradionecrosis, and one examined HBO in bisphosphonate-related necrosis of the jaws.

CONCLUSIONS

HBO has shown superior efficacy compared to antibiotics as a prophylactic measure in preventing osteoradionecrosis (ORN) in patients with a history of high mandibular irradiation. Clinicians should consider referring such patients for HBO therapy before and after tooth extractions. However, for the surgical excision of existing ORN lesions, HBO therapy does not yield significant benefits but does not negatively impact outcomes either. Regarding the treatment of periodontitis patients, the variability among studies prevents definitive conclusions. HBO therapy as an adjunct to SRP in periodontitis treatment produces mixed results.

CLINICAL RELEVANCE

This study's clinical relevance lies in its exploration of the potential benefits of HBO for periodontal conditions. Also, it provides clinicians with insights into when and how to integrate HBO therapy into their treatment approaches, particularly for patients with a history of irradiation and those undergoing complex dental procedures.

Tooth-Supported Overdentures Revisited

The goal of prosthodontics is to provide a functional prosthesis to restore aesthetics, functions, and masticatory efficiencies. Tooth-supported overdentures are one of the treatment options for removable dentures. This article aims to discuss the advantages and disadvantages of tooth-supported overdentures and the principles of using various overdenture attachments, including non-attachment overdentures. The common treatment options in preparing the overdenture abutment are either with or without abutment coping with or without attachment systems, which were discussed and illustrated. A range of tooth-supported overdenture systems were addressed, from low to high financial implications and treatment complexities. The clinician can choose a system that best fits the patient's condition and expectations. This allows clinicians to decide and consider tooth-supported overdentures as a treatment option before full edentulism. A well-executed tooth-supported overdenture ensures the preservation of alveolar bone, optimizes patient satisfaction in denture treatment, and eventually improves the patient's adaptation when transitioning to complete dentures.

The impact of radiation caries on morbidity and mortality outcomes of head and neck squamous cell carcinoma patients

AIMS

Radiation caries (RC) is a highly prevalent and chronic complication of head and neck radiotherapy (HNRT) and presents a challenge for clinicians and patients. The present study aimed to assess the impact of RC on the morbidity and mortality outcomes of head and neck squamous cell carcinoma (HNSCC) patients.

METHODS AND RESULTS

Patients were divided into three groups: (1) RC (n = 20), (2) control (n = 20), and (3) edentulous (n = 20). Information regarding the number of appointments, dental procedures, osteoradionecrosis (ORN), prescriptions, and hospital admissions were collected. Mortality outcomes were assessed through disease-free survival (DFS) and overall survival (OS) rates. RC patients required more dental appointments (p < .001), restorations (p < .001), extractions (p = .001), and antibiotic and analgesic prescriptions (p < .001). Kaplan-Meier subgroup analyses showed a significantly increased risk of ORN in RC compared to edentulous patients (p = .015). RC patients presented lower DFS rates (43.2 months) than the control and edentulous groups (55.4 and 56.1 months, respectively).

CONCLUSIONS

RC impacts morbidity outcomes among cancer survivors due to increased demand for medication prescriptions, multiple specialized dental appointments, invasive surgical treatments, increased risk of ORN, and increased need for hospital admissions.

Oral Surgery and Osteoradionecrosis in Patients Undergoing Head and Neck Radiation Therapy: An Update of the Current Literature

Osteoradionecrosis (ORN) is a serious long-term complication of head and neck radiotherapy (RT), which is often triggered by dental extractions. It results from avascular aseptic necrosis due to irradiated bone damage. ORN is challenging to treat and can lead to severe complications. Furthermore, ORN causes pain and distress, significantly reducing the patient's quality of life. There is currently no established preventive strategy. This narrative review aims to provide an update for the clinicians on the risk of ORN associated with oral surgery in head and neck RT patients, with a focus on the timing suitable for the oral surgery and possible ORN preventive treatments. An electronic search of articles was performed by consulting the PubMed database. Intervention and observational studies were included. A multidisciplinary approach to the patient is highly recommended to mitigate the risk of RT complications. A dental visit before commencing RT is highly advised to minimize the need for future dental extractions after irradiation, and thus the risk of ORN. Post-RT preventive strategies, in case of dento-alveolar surgery, have been proposed and include antibiotics, hyperbaric oxygen (HBO), and the combined use of pentoxifylline and tocopherol ("PENTO protocol"), but currently there is a lack of established standards of care. Some limitations in the use of HBO involve the low availability of HBO facilities, its high costs, and specific clinical contraindications; the PENTO protocol, on the other hand, although promising, lacks clinical trials to support its efficacy. Due to the enduring risk of ORN, removable prostheses are preferable to dental implants in these patients, as there is no consensus on the appropriate timing for their safe placement. Overall, established standards of care and high-quality evidence are lacking concerning both preventive strategies for ORN as well as the timing of the dental surgery. There is an urgent need to improve research for more efficacious clinical decision making.

Dental Extractions Before Radiation Therapy and the Risk of Osteoradionecrosis in Patients With Head and Neck Cancer

Importance

Patients with head and neck cancer undergo extraction of teeth with poor prognoses to minimize post-radiation therapy (RT) extractions, which are known to cause osteoradionecrosis (ORN). However, many patients are required to start RT before the extraction sites are completely healed. The role of pre-RT extractions in the development of ORN has been disputed in literature.

Objective

To determine whether the timing of pre-RT dental extractions is associated with ORN development in patients with head and neck cancer.

Design, Setting, and Participants

This retrospective cohort study was conducted at a single institution (Princess Margaret Cancer Centre, Toronto, Canada) between January 1, 2011, and January 1, 2018, and included 879 patients with head and neck cancer who underwent pre-RT dental extractions before curative RT of 45 Gy or greater. Patient demographic information and clinical characteristics (eg, primary cancer site, nodal involvement, chemotherapy, smoking status, dental pathology) were considered. Data analyses were performed from July to December 2022.

Main outcomes and measures

Timing (number of days) from dental extractions to RT start date and pre-RT extractions categorized as healed, minor bone spicules (MBS), or ORN.

Results

The study population consisted of 879 patients with a median (range) age of 62 (20-96) years, with 685 men (78%) and 194 women (22%). Of these, 847 (96.3%) healed from pre-RT dental extractions, 16 (1.8%) developed MBS, and 16 (1.8%) developed ORN. The median (range) time in number of days from pre-RT extraction(s) to start of RT was 9 (0-98) days in the healed cohort, 6 (3-23) days in the MBS cohort, and 6 (0-12) days in the ORN cohort. There was a large difference in the timing of pre-RT extractions between the healed and the MBS cohorts (mean 11.9 vs 7.4 days to radiation; difference 4.4; 95% CI, 1.5-7.3), and the healed and the ORN cohorts (mean 11.9 vs 7.1 days; difference 4.8 days; 95% CI, 2.6-7.1).

Conclusion

The findings of this retrospective cohort study suggest that there was an important association between the timing of pre-RT dental extractions and ORN when extractions occurred within 7 days of the RT start date. Despite this, ORN after pre-RT extractions is relatively rare. These findings indicate that patients with head and neck cancer who are to undergo RT should not delay treatment for extractions when it might compromise oncologic control.

Compliance with oral hygiene and dietary advice for the prevention of post-radiotherapy dental disease among head and neck cancer patients - a qualitative study

OBJECTIVES

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.

METHODS

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.

RESULTS

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.

CONCLUSIONS

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.

CLINICAL SIGNIFICANCE

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.

Effects of systemic Anatolian propolis administration on a rat-irradiated osteoradionecrosis model

OBJECTIVE

Radiotherapy after head and neck cancer is associated with the risk of osteonecrosis development. This study aims to investigate the effectiveness of systemic propolis application to prevent the disease as it has no definite treatment protocol despite the proposed treatment methods and significantly decreases individuals' quality of life.

METHODOLOGY

In total, 29 male Wistar-Albino rats were divided into control, 35 Gy irradiation (Group 1), 35 Gy irradiation+100 mg/kg/ml propolis administration (Group 2), and 35 Gy irradiation+200 mg/kg/ml propolis administration groups (Group 3). Propolis was first applied on the day after radiotherapy, except for the control group. Right first and second molars were extracted from all rats three weeks following radiotherapy. Samples were collected seven weeks after radiotherapy. Osteoblast and osteoclast counts were calculated by histomorphometric analysis. Immunohistochemical analysis determined bone morphogenic protein-2 (BMP-2) and transforming growth factor beta-3 (TGFβ-3).

RESULTS

Group comparison found non-significant differences regarding osteoblast (p=0.130) and osteoclast (p=0.063) counts. However, Group 1 showed the lowest mean osteoblast (OBL: 82.63 [±13.10]) and highest mean osteoclast counts (OCL: 12.63 [±5.55]). OBL/OCL ratio showed significant differences between groups (p=0.011). Despite the significant difference between the Control and Groups 1 (p=0.006) and 2 (p=0.029), Group 3 showed a non-significant difference (p=0.091). For BMP-2 and TGFB3, the control group showed significant differences with the other two groups (p<0.001), except for Group 3.

CONCLUSION

Anatolian propolis showed beneficial effects in a radiotherapy-mediated osteonecrosis model, highlighting its potential as a promising intervention.

Oral Complications from Oropharyngeal Cancer Therapy

Post-oropharyngeal cancer treatment complications include a multitude of oral side effects that impact overall survival and quality of life. These include acute and chronic conditions affecting the oral cavity and head and neck, such as mucositis, infection, xerostomia, dysgeusia, radiation caries, osteonecrosis, and trismus. This review will summarize the most common oral complications from oropharyngeal cancer therapy. The authors would like to point out that the literature cited frequently combines oropharyngeal and head and neck cancer results. If recommendations are made strictly related to oropharyngeal cancers, this will be highlighted.

An umbrella review exploring the effect of radiotherapy for head and neck cancer patients on the frequency of jaws osteoradionecrosis

OBJECTIVE

Efforts have been made to reduce epidemiological indicators of osteoradionecrosis in patients with head and neck cancer over recent years. This umbrella review aims to synthesize the information of the systematic reviews/meta-analyses investigating the effect of radiotherapy in patients with head and neck cancer on the frequency of osteoradionecrosis and to identify and analyze the gaps in current scientific literature.

MATERIAL AND METHODS

A systematic review of systematic reviews with and without meta-analysis of intervention studies was conducted. Qualitative analysis of the reviews and their quality evaluation were performed.

RESULTS

A total of 152 articles were obtained, and ten of them were selected for the final analysis, where six were systematic reviews and four were meta-analysis. According to the guide Assessing the Methodological Quality of Systematic Reviews (Amstar), eight articles included were of high quality and two of medium quality. These descriptive systematic reviews/meta-analyses included a total of 25 randomized clinical trials, showing that radiotherapy has positive effects on the frequency of osteoradionecrosis. Even though a reduction in the incidence of osteoradionecrosis was observed back in the history, in systematic reviews with meta-analysis, overall effect estimators were not significant.

CONCLUSIONS

Differential findings are not enough to demonstrate that there is a significant reduction in the frequency of osteoradionecrosis in patients with head and neck cancer treated by radiation. Possible explanations are related to factors such as the type of studies analyzed, indicator of irradiated complication considered, and specific variables included in the analysis. Many systematic reviews did not address publication bias and did identify gaps in knowledge that require further clarification.

The role of hyperbaric oxygen in osteoradionecrosis-a prophylactic insight

BACKGROUND

Osteoradionecrosis (ORN) is an uncommon and debilitating consequence of head and neck radiotherapy and hyperbaric oxygen therapy (HBOT) has been advocated for prophylaxis prior to performing dentoalveolar procedures. The aim of this study was to evaluate a prophylactic HBOT protocol and describe the outcomes of susceptible individuals.

METHODS

A retrospective audit of adults who attended the Oral and Maxillofacial Surgery department at the Royal Adelaide Hospital (South Australia) who received dental extractions with a history of radiotherapy to the jaws from 2008 to 2020. Data including demographic information and outcomes of osteoradionecrosis and delayed healing was recorded.

RESULTS

A total of 121 individuals were eligible for case note review; 68.6% of individuals were male and 55.4% were aged over 67 years. Osteoradionecrosis occurred in 9.1% of individuals and delayed healing for 3.3%; fifteen individuals (12.4%) were unable to complete the HBOT protocol. The individuals who were diagnosed with ORN had a significant association with age (P = 0.006) and binary analysis showed alcohol consumption to be a significant predictor.

CONCLUSIONS

Prophylactic HBOT protocol had a lower proportion of individuals diagnosed with ORN and those who were diagnosed were more likely to be younger males and have current alcohol consumption.

Dental considerations for head and neck cancer: A clinical review

Introduction

Radiotherapy is one of the treatment modalities for the treatment of head and neck cancer (HNC). However, it leads to the development of chronic and acute side effects. These side effects impact negatively on the patient's quality of life and oral functioning. This clinical review aims to provide basic information about HNC, understand the impact of radiotherapy on oral health, and explain the role of dental care providers for HNC patients during the pre-and post-radiotherapy time.

Materials and Methods

Electronic databases (i.e., PubMed, Scopus, and Google Scholar) were searched using defined keywords. The main inclusion criteria were any studies describing "dental management of patients with head and neck cancer" and "dental management of patients treated with radiotherapy."

Results

Thematic analysis was used to summaries the findings of the included studies (n = 102) into main headings and subheadings. All studies were published between 1970 and 2023.

Conclusion

The number of HNC patients is increasing. This necessitates the need for raising the awareness of dental care providers to the side-effects of HNC therapy which includes treatment with radiotherapy, chemotherapy, and/or surgery. Dental care providers should understand the common side-effects and their treatments besides their role in the pre- (i.e., dental extraction of teeth with poor prognosis and maintaining good oral hygiene) and post- (i.e., oral rehabilitation and post-HNC dental care) radiotherapy dental care.

Can the prophylactic use of pentoxifylline and tocopherol before dental extractions prevent osteoradionecrosis? A systematic review

PURPOSE

This systematic review aimed to determine whether the pentoxifylline and tocopherol (PENTO) protocol effectively reduce the risk of osteoradionecrosis (ORN) in patients undergoing tooth extraction after head and neck radiotherapy.

METHODS

We searched PubMed, SCOPUS, LILACS, EMBASE, Web of Science, and Cochrane databases up to August 2022. We considered only studies that included patients diagnosed with head and neck cancer undergoing tooth extraction with PENTO prophylaxis after radiotherapy.

RESULTS

Of the 642 studies identified, 4 were included. Across the included studies, 387 patients had 1871 teeth extracted while on PENTO prophylaxis. The interval of the PENTO protocol differed among the studies included. Overall, a total of 12 (3.1%) patients had ORN, whereas at the individual tooth level analysis the ORN rate was 0.9%.

CONCLUSIONS

Insufficient evidence exists to promote using the PENTO protocol before dental extractions to prevent ORN.

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.

Dose Escalation of Oropharyngeal Cancer: Long-Time Follow-Up and Side Effects

Previous studies on dose-escalated radiotherapy in head and neck cancer have shown mixed results, and it is not established which patients would benefit from dose escalation. Further, while dose escalation does not appear to increase late toxicity, this needs to be confirmed with longer follow-up. In this study, we analysed treatment outcome and toxicity in 215 patients with oropharyngeal cancer treated with dose-escalated radiotherapy (>72 Gy, EQD2, α/β = 10 Gy, boost by brachytherapy or simultaneous integrated boost) and a matched cohort of 215 patients treated with standard dose external-beam radiotherapy (68 Gy) between 2011 and 2018 at our institution. The 5-year overall survival (OS) was 77.8% (72.4-83.6) and 73.7% (67.8-80.1) in the dose-escalated and standard dose group, respectively (p = 0.24). Median follow-up was 78.1 (49.2-98.4) and 60.2 (38.9-89.4) months in the dose-escalated and standard dose groups, respectively. Grade ≥3 osteoradionecrosis (ORN) and late dysphagia were more common in the dose-escalated group compared to the standard dose group, with 19 (8.8%) vs. 4 (1.9%) patients developing grade ≥3 ORN (p = 0.001), and 39 (18.1%) vs. 21 (9.8%) patients developing grade ≥3 dysphagia (p = 0.01). No predictive factors to help select patients for dose-escalated radiotherapy were found. However, the remarkably good OS in the dose-escalated cohort, despite a predominance of advanced tumour stages, encourages further attempts to identify such factors.

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.

Planned dose of intensity modulated proton beam therapy versus volumetric modulated arch therapy to tooth-bearing regions

BACKGROUND

Intensity modulated proton beam therapy (IMPT) for head and neck cancer offers dosimetric benefits for the organs at risk when compared to photon-based volumetric modulated arch therapy (VMAT). However, limited data exists about the potential benefits of IMPT for tooth-bearing regions. The aim of this study was to compare the IMPT and VMAT radiation dosimetrics of the tooth-bearing regions in head and neck cancer patients. Also, we aimed to identify prognostic factors for a cumulative radiation dose of ≥40 Gy on the tooth-bearing areas, which is considered the threshold dose for prophylactic dental extractions.

METHODS

A total of 121 head and neck cancer patients were included in this retrospective analysis of prospectively collected data. We compared the average Dmean values of IMPT versus VMAT of multiple tooth-bearing regions in the same patients. Multivariate logistic regression analysis was performed for receiving a cumulative radiation dose of ≥40 Gy to the tooth-bearing regions (primary endpoint) in both VMAT and IMPT.

RESULTS

A lower Dmean was seen after applying IMPT to the tooth-bearing tumour regions (p < 0.001). Regarding VMAT, oral cavity tumours, T3-T4 tumours, molar regions in the mandible, and regions ipsilateral to the tumour were risk factors for receiving a cumulative radiation dose of ≥40 Gy.

CONCLUSIONS

IMPT significantly reduces the radiation dose to the tooth-bearing regions.

Dose escalation in oropharyngeal cancer: a comparison of simultaneous integrated boost and brachytherapy boost

BACKGROUND

Local recurrence is the most common pattern of failure in head and neck cancer. It can therefore be hypothesised that some of these patients would benefit from an intensified local treatment, such as radiation dose escalation of the primary tumour. This study compares treatment and toxicity outcomes from two different boost modalities in oropharyngeal cancer: simultaneous integrated boost (SIB) and brachytherapy boost.

METHODS

Two hundred and forty-four consecutive patients treated with > 72 Gy for oropharyngeal squamous cell carcinoma between 2011 and 2018 at our institution were retrospectively analysed. Data on side effects were collected from a local quality registry and supplemented with a review of medical records. Patients receiving a brachytherapy boost first had external beam radiotherapy consisting of 68 Gy in 2 Gy fractions to the gross tumour volume (GTV), and elective radiotherapy to the neck bilaterally. The brachytherapy boost was typically given using pulsed dose rate, 15 fractions and 0.56-0.66 Gy per fraction [total dose in EQD2 = 75.4-76.8 Gy (α/β = 10)]. The typical dose escalated radiotherapy with external beam radiotherapy only, was delivered using SIB with 74,8 Gy in 2.2 Gy fractions [EQD2 = 76.0 Gy (α/β = 10)] to the primary tumour, 68 Gy in 2 Gy fractions to GTV + 10 mm margin and elective radiotherapy to the neck bilaterally.

RESULTS

Dose escalation by SIB was given to 111 patients and brachytherapy boost to 134 patients. The most common type of cancer was base of tongue (55%), followed by tonsillar cancer (42%). The majority of patients had T3- or T4-tumours and 84% were HPV-positive. The 5-year OS was 72,4% (95% CI 66.9-78.3) and the median follow-up was 6.1 years. Comparing the two different dose escalation modalities we found no significant differences in OS or PFS and these results remained after a propensity-score matched analysis was performed. The analysis of grade ≥ 3 side effects showed no significant differences between the two different dose escalation techniques.

CONCLUSIONS

We found no significant differences in survival or grade ≥ 3 side effects comparing simultaneous integrated boost and brachytherapy boost as alternative dose escalation modalities in the treatment of oropharyngeal cancer.

Association between tooth extraction during radiotherapy and the risk of osteoradionecrosis in patients with head and neck cancers

PURPOSE

It is commonly recommended that tooth extraction should be performed prior to radiotherapy (RT) in patients with head neck cancer to prevent osteoradionecrosis (ORN). However, doctors still occasionally encounter patients who require tooth extraction during RT. This study aimed to determine the risk of ORN in patients who undergo tooth extraction during RT.

METHODS

Data were collected from Taiwan's National Health Insurance Research Database. We retrospectively enrolled 24,412 patients with head and neck cancer treated with radiotherapy between 2011 and 2017. The associations between ORN and demographic characteristics, timing of tooth extraction, and treatments were examined using univariate and multivariable Cox proportional hazards regression models.

RESULTS

A total of 24,412 head and neck cancer patients were enrolled; 133 patients underwent tooth extraction during RT and 24,279 patients did not undergo tooth extraction during RT. Tooth extraction during RT was not associated with a significantly higher risk of ORN (hazard ratio [HR] = 1.303, P = 0.4862). Tumor site, RT dose ≥ 60 Gy, age < 55 y/o, mandibulectomy, chronic periodontitis, and chemotherapy were significantly associated with a higher risk of ORN.

CONCLUSION

The risk of ORN in head and neck cancer is not significantly different between patients who undergo tooth extraction during RT and patients who do not undergo tooth extraction during RT.

Pentoxifylline and tocopherol for prevention of osteoradionecrosis in patients who underwent oral surgery: A clinical audit

PURPOSE

Osteoradionecrosis (ORN) of the jaw is a severe and debilitating complication of the head and neck radiotherapy which frequently occurrs after oral surgery. This clinical audit aims aevaluate the effectiveness of combined use of pentoxifylline and tocopherol (PENTO) in prevention ORN onset in patient who underwent oral surgery after head and neck radiotherapy (RT).

MATERIAL METHOD

In this clinical audit Pentoxifylline 400 mg, twice a day, and Tocopherol 800 IU once a day (PENTO protocol) have been prescribed. Patients started the protocol 1 week before the surgical procedure and continued for 8 weeks after.

RESULTS

Twenty-nine patients were included. They received 75 surgical interventions under PENTO protocol: 71 surgical procedures of dental extraction (single or multiple dental extractions in each session) and four implant placements. A total of 152 dental extractions were carried out: 64 surgical extractions which required the raising of mucoperiosteal flap, and 88 simple extractions. Four out of 29 patients developed ORN after surgical procedures: four cases of ORN occurred after dental extractions (5.6%) and one case of ORN after implant placement (25%).

CONCLUSION

PENTO is a useful ORN preventive protocol, low-cost and clinically feasible, safe and well tolerated by patients. Further studies should focus on better defining the effectiveness PENTO, independently from the antibiotic therapy.

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.

Systematic dosimetric evaluation of risk of osteoradionecrosis (DERO): First results of dose reporting for preventing teeth osteoradionecrosis after head and neck irradiation

PURPOSE

OsteoRadioNecrosis (ORN) is a late complication of radiation for head and neck cancer. Predicting ORN is a major challenge. We developed DERO (Dosimetric Evaluation of Risk of ORN), a semi-automatic tool which reports doses delivered to tooth-bearing sectors, to guide post-therapeutic dental care. We present the method and the first results of a 125-patient prospective cohort.

MATERIAL AND METHODS

Dosimetric data of patients treated with IMRT for head and neck cancer were prospectively segmented to the DERO algorithm. Four arches corresponding to 8-tooth sectors were semi-automatically generated. Thirty-two cylindrical Regions Of Interest (ROI) corresponding to each tooth and surrounding periodontium were created by linear interpolation. Mean doses (Dmean) of ROI were extracted and included in a database, along with data about primary tumor site, laterality and dose values from organs at risk. Dmean to tooth sectors were computed for molar sectors, (teeth X5 to X8) and anterior sectors (teeth X1 to X4). An individual dose map was generated and delivered to patients and dentists.

RESULTS

Dosimetric data from 125 patients treated with Tomotherapy® were prospectively collected and analyzed: 9 parotid tumors (PA), 41 Sub-Hyoid tumors (larynx, hypopharynx) (SH), 43 Oropharynx tumors (OR), 32 Oral Cavity tumors (OC). Irradiation was unilateral for 100% of PA tumors (9), 12% of OR tumors (5) and 47% of OC tumors (15). For unilateral cervical irradiation, Dmean in ipsilateral molar sectors was 54Gy for OC tumors, 45Gy for OR tumors, 20Gy for PA tumors. For Oral Cavity bilateral irradiation, Dmean was high in all tooth sectors, 49 to 55Gy. For SH tumors, Dmean in molar sectors was 27Gy. A dose gradient of 10 to 20Gy was observed between molar and anterior sectors whether radiation was uni or bilateral.

CONCLUSION

Mandibular molar sectors of Oropharynx and Oral Cavity tumors were exposed to high Dmean of 40 to 50Gy. On the other hand, tooth sectors received lower doses for SH radiation. The DERO tool guide post-radiation dental care with a personalized dosimetric cartography to patient. With data update and patient follow-up, we will be able to determine ORN risk after head and neck radiation.

Osteonecrosis of the Jaw

Osteonecrosis of the jaw is a condition in which bone cells die due to various causes. It is classified as drug-induced jaw osteonecrosis, osteoradionecrosis, traumatic, non-traumatic, and spontaneous osteonecrosis. Antiresorptive or antiangiogenic drugs cause drug-induced osteonecrosis. The combination of medications, microbial contamination, and local trauma induces this condition. Osteoradionecrosis is a severe radiation therapy side effect that can affect people with head and neck cancer. It is described as an exposed bone area that does not heal for longer than three months after the end of radiation treatment with the absence of any indications of an original tumor, recurrence, or metastasis. Trauma (tooth extraction), tumor site, radiation dose that the patient receives, the area of the bone which is irradiated, oral hygiene, and other factors are risk factors for the development of osteonecrosis. Less frequently, osteonecrosis can also be induced by non-traumatic and traumatic causes. Non-traumatic osteonecrosis is brought on by infections, acquired and congenital disorders, as well as the impact of chemicals. Traumatic osteonecrosis is brought on by thermal, mechanical, or chemical damage. The treatment of osteonecrosis can be conservative, which aims to be beneficial for the patient's quality of life, and surgical, which involves debridement of the necrotic bone.

Osteoradionecrosis versus Cancer Recurrence: An Unresolved Clinical Dilemma

INTRODUCTION

Osteoradionecrosis is a rare and debilitating risk of definitive chemoradiotherapy for head and neck squamous cell carcinoma. It is difficult to distinguish between osteoradionecrosis and recurrent or progressive disease, as clinical and radiologic features may be similar. Our aim was to compare the clinical presentation and radiologic features of osteonecrosis with those of recurrent or progressive cancer.

METHODS

We conducted a single-center case series of 19 patients with head and neck squamous cell carcinoma diagnosed between 2011 and 2019 who subsequently developed clinical and/or radiological suspicion of osteoradionecrosis. The population was a referred sample from head and neck cancer physicians at Northwell Health Cancer Institute. Clinician notes and imaging reports were reviewed to assign a final diagnosis of either cancer, osteonecrosis, or indeterminate.

RESULTS

No differences were found in the clinical presentation or radiologic features between groups. Median time between treatment and development of symptoms was longer in patients with a final diagnosis of osteoradionecrosis than recurrent or progressive disease (5 vs. 3 months), but this difference was not statistically significant. Radiation dose and type were not associated with diagnosis. Mean standard uptake value maximums on positron emission tomography/computed tomography were significantly higher in the cancer group (median 14.8 vs. 9.1, p < 0.0152). At 1 year after first suspicion of osteoradionecrosis, 100% of osteoradionecrosis patients were alive, versus 28.6% of cancer patients.

DISCUSSION/CONCLUSION

There is significant overlap in clinical and radiologic features of osteoradionecrosis and cancer. Standard uptake maximums may be helpful in predicting diagnosis. Occurrence of symptoms within 6 months of completing chemoradiotherapy should raise the concern for malignancy.

A Narrative Review on Means to Promote Oxygenation and Angiogenesis in Oral Wound Healing

Oral mucosa serves as the primary barrier against pathogen invasions, mechanical stresses, and physical trauma. Although it is generally composed of keratinocytes and held in place by desmosomes, it shows variation in tissue elasticity and surface keratinization at different sites of the oral cavity. Wound healing undergoes four stages of tissue change sequences, namely haemostasis, inflammation, proliferation, and remodelling. The wound healing of oral hard tissue and soft tissue is largely dependent on the inflammatory response and vascular response, which are the targets of many research. Because of a less-robust inflammatory response, favourable saliva properties, a unique oral environment, and the presence of mesenchymal stem cells, oral wounds are reported to demonstrate rapid healing, less scar formation, and fewer inflammatory reactions. However, delayed oral wound healing is a major concern in certain populations with autoimmune disorders or underlying medical issues, or those subjected to surgically inflicted injuries. Various means of approach have been adopted to improve wound tissue proliferation without causing excessive scarring. This narrative review reappraises the current literature on the use of light, sound, mechanical, biological, and chemical means to enhance oxygen delivery to wounds. The current literature includes the use of hyperbaric oxygen and topical oxygen therapy, ultrasounds, lasers, platelet-rich plasma (PRP)/platelet-rich fibrin (PRF), and various chemical agents such as hyaluronic acid, astaxanthin, and Centella asiatica to promote angiogenesis in oral wound healing during the proliferation process. The arrival of a proprietary oral gel that is reported to improve oxygenation is highlighted.

Osteoradionecrosis rate in oropharynx cancer treated with dose volume histogram based constraints

OBJECTIVES

Mandibular dose constraints are designed to limit high dose to small volumes to avoid osteoradionecrosis (ORN). Based upon a published experience, intermediate-dose constraints were introduced but have not been independently validated. We hypothesize that these constraints lower ORN rate without compromising other organs at risk (OAR).

METHODS

Oropharyngeal cancer patients treated with standard fractionation adjuvant/definitive VMAT from 01/2014-08/2020 were included. In 09/2017, mandibular dose constraint was changed from historical constraint (HC) of D 0.1 cc < 70 Gy to modified constraints (MC) of V 44 Gy < 42%, V 58 Gy < 25%, D 0.5 cc < 70 Gy. OAR dosimetric changes and ORN development were evaluated. Regression modelling predicted long-term ORN cases in MC group.

RESULTS

There were 174 patients, 71 in MC group. Seven cases of ORN in HC group at a median follow up (FU) of 39 months and 1 case of ORN in MC group at a median FU of 11 months were observed. More patients in the MC group met V 44 Gy (87% vs 62%, p < 0.01) and V 58 Gy constraints (92% vs 73%, p < 0.01). Mean doses to OARs did not rise. Mandible V 44 Gy and V 58 Gy were significantly associated with ORN (p < 0.01 and p = 0.03, respectively) across all patients. In the HC group, V 44 Gy was independently associated with ORN (p = 0.01). To account for shorter FU in MC group, logistic regression of ORN based on V 44 Gy in HC patients was performed. This predicts 3.2 ORN cases in the MC group (95% CI: 0.00-6.4).

CONCLUSION

Achieving V 44 Gy and V 58 Gy was successful in 87% of cases without sacrificing target coverage or OARs and resulted in non-significant ORN decrease.

Efficacy of photobiomodulation therapy on healing of ionizing irradiated bone: a systematic review of in vivo animal studies

This systematic review aimed to answer the research focused question: What are the effects of photobiomodulation (PBM) therapy on bone healing after ionizing irradiation in animal models? The EMBASE, LILACS, LIVIVO, PubMed, Scopus, and Web of Science databases, including gray literature, were searched using the following keywords: "Head and Neck Neoplasms"; "Ionizing Radiation"; "Low-Level Light Therapy"; and "Bone regeneration", focusing on the primary studies that assessed the effects of PBM therapy on animal models of irradiated bone. Six studies have met the eligibility criteria and presented an overall regular quality according to the risk of bias assessment tools. All the studies utilized rat animal model and near-infrared laser PBM at low power output setting. Most of the studies showed increased new bone formation, osteocytes, osteoblasts, and vascularization networking, as a result of PBM therapy. However, only one out of the six studies has not shown any differences in bone healing in both lased and non-lased animal groups. Nevertheless, PBM therapy is a potential tool to improve bone healing induced by ionizing radiation. However, due to the scarce number of studies and the great variability of laser parameters and treatment protocols, a clear conclusion cannot be drawn. Hence, extensive preclinical in vivo studies are warranted to ensure these beneficial effects have been addressed prior to translational clinical trials.

Irradiation Induced Biochemical Changes in Human Mandibular Bone: A Raman Spectroscopic Study

Understanding the biochemical changes in irradiated human mandible after radiotherapy of cancer patients is critical for oral rehabilitation. The underlying mechanism for radiation-associated changes in the bone at the molecular level could lead to implant failure and osteoradionecrosis. The study aimed to assess the chemical composition and bone quality in irradiated human mandibular bone using Raman spectroscopy. A total of 33 bone biopsies from 16 control and 17 irradiated patients were included to quantify different biochemical parameters from the Raman spectra. The differences in bone mineral and matrix band intensities between control and irradiated groups were analyzed using unpaired Student's t-test with statistical significance at p < 0.05. Findings suggest that the intensity of the phosphate band is significantly decreased and the carbonate band is significantly increased in the irradiated group. Further, the mineral crystallinity and carbonate to phosphate ratio are increased. The mineral to matrix ratio is decreased in the irradiated group. Principal component analysis (PCA) based on the local radiation dose and biopsy time interval of irradiated samples did not show any specific classification between irradiation sub-groups. Irradiation disrupted the interaction and bonding between the organic matrix and hydroxyapatite minerals affecting the bone biochemical properties. However, the normal clinical appearance of irradiated bone would have been accompanied by underlying biochemical and microscopical changes which might result in radiation-induced delayed complications.

Osteoradionecrosis of the jaw: A mini review

Osteoradionecrosis (ORN) of the jaw is one of the most dreaded complications of head and neck radiation therapy. Despite the evolution of radiation treatment modalities, ORN continues to remain a therapeutic challenge and its etiopathogenesis still remains unclear. It is clinically characterized by exposed necrotic bone within the head and neck radiation field. Over the past years, several studies have reported on the definition, staging, incidence, etiology, and management of this oral complication. In this review, we summarize the literature on ORN and discuss our institutional experience and management strategies that aim to predict and mitigate risk for ORN.

Response Evaluation Following Radiation Therapy With 18F-FDG PET/CT: Common Variants of Radiation-Induced Changes and Potential Pitfalls

Radiation therapy (RT) is one of the cornerstones in cancer treatment and approximately half of all patients will receive some form of RT during the course of their cancer management. Response evaluation after RT and follow-up imaging with ¹⁸F-Fluorodeoxyglucose (¹⁸F-FDG) positron emission tomography/computed tomography (PET/CT) can be complicated by RT-induced acute, chronic or consequential effects. There is a general consensus that ¹⁸F-FDG PET/CT for response evaluation should be delayed for 12 weeks after completing RT to minimize the risk of false-positive findings. Radiation-induced late side effects in normal tissue can take years to develop and eventually cause symptoms that on imaging can potentially mimic recurrent disease. Imaging findings in radiation induced injuries depend on the normal tissue included in the irradiated volume and the radiation therapy regime including the total dose delivered, dose per fraction and treatment schedule. The intent for radiation therapy should be taken in consideration when evaluating the response on imaging, that is palliative vs curative or neoadjuvant vs adjuvant RT. Imaging findings can further be distorted by altered anatomy and sequelae following surgery within the radiation field. An awareness of common PET/CT-induced changes/injuries is essential when interpreting ¹⁸F-FDG PET/CT as well as obtaining a complete medical history, as patients are occasionally scanned for an unrelated cause to previously RT treated malignancy. In addition, secondary malignancies due to carcinogenic effects of radiation exposure in long-term cancer survivors should not be overlooked. ¹⁸F-FDG PET/CT can be very useful in response evaluation and follow-up in patients treated with RT, however, variants and pitfalls are common and it is important to remember that radiation-induced injury is often a diagnosis of exclusion.

The impact of hyperbaric oxygen therapy on late irradiation injury in oral microcirculation

BACKGROUND

Late side effects of radiotherapy in patients with head and neck cancer (HNCPs) result in decreased tissue vascularity, a compromised healing capacity and spontaneous breakdown of tissue. The aim of this study was to examine the in vivo effect of hyperbaric oxygen therapy (HBOT) on the microcirculation in irradiated oral tissue.

METHODS

Using a handheld microscope, the effect of HBOT on oral mucosal microcirculation parameters was measured in 34 previously irradiated HNCPs prior to HBOT and at 4 weeks and 6 months posttreatment.

RESULTS

A significant increase in mean buccal vessel density and decrease in buccal vessel diameter was found 6 months after HBOT compared to baseline, 22 ± 11 versus 25 ± 7 cpll/mm2 (p < 0.05) and 20 ± 4 versus 16 ± 5 μm (p < 0.05), respectively.

CONCLUSION

Our results indicate that oral microcirculation histopathology associated with irradiation is able to respond to HBOT by redirecting oral microcirculation parameters towards values consistent with healthy tissue.

One Third of Patients before Endoprosthesis Implantation Show an Oral Focus as Potential Source of Infectious Complication—The Value of Pre-Operative Dental Risk Stratification in a German Cohort

Objective: The aim of this cross-sectional cohort study was to evaluate a comprehensive dental examination and referral concept for patients prior to endoprosthesis (EP) implantation in an interdisciplinary setting. Methods: Patients, who were prepared for EP surgery in the clinic for orthopaedics, were referred to the dental clinic for a dental examination. Thereby, dental and periodontal treatment need, radiographic and temporomandibular joint findings were assessed. Based on oral and radiographic investigation, a risk classification for potential source of prosthetic infection was performed. If potential oral foci of EP infection were present (e.g., apically radiolucent teeth, severe periodontitis or additional inflammatory findings), patients were classified as at high risk for EP infection with oral origin. Those individuals were allocated to their family dentist or special clinic for dental treatment prior to EP surgery. Results: A total of 311 patients were included (mean age: 67.84 ± 10.96 years, 51% male). A dental treatment need of 33% was found, while the periodontal treatment need was 83%. Thirty-one percent of patients showed at least one apical radiolucency (a sign of chronic infection/inflammation). Furthermore, additional findings such as radiographic signs of sinusitis maxillaris were found in 24% of patients. Temporomandibular disease was probable in 17% of individuals. One-third (34%) were assigned to the high risk group for an EP infection with oral origin. Conclusion: German patients before EP have a high periodontal treatment need and show frequently (34%) a potential oral focus of infection, underlining the necessity of including dental examination and risk stratification as part of the pre-operative assessment prior to EP implantation. Therefore, an approach as applied in this study appears reasonable for those individuals.