Prevalence of free flap failure in mandibular osteoradionecrosis reconstruction: a systematic review and meta-analysis.

Our study aimed to estimate the prevalence of total free flap failure following free flap reconstruction for mandibular osteoradionecrosis (mORN) and assess the impact of potential moderators on this outcome. A comprehensive systematic literature search was independently conducted by two reviewers using the Medline, Scopus, Web of Science and Cochrane Library databases. Quality assessment of the selected studies was performed, and prevalence estimates with 95% confidence intervals (CI) were calculated. Outlier and influential analyses were conducted, and meta-regression analyses was employed to investigate the effects of continuous variables on the estimated prevalence. Ultimately, forty-six eligible studies (involving 1292 participants and 1344 free flaps) were included in our meta-analysis. The findings of our study revealed a prevalence of 3.1% (95% CI 1.3-5.4%) for total free flap failure after reconstruction for mORN. No study was identified as critically influential, and meta-regression analysis did not pinpoint any potential sources of heterogeneity. These findings provide valuable insights for researchers and serve as a foundation for future investigations into the management of mandibular osteoradionecrosis and the prevention of free flap failure in this context.

The incidence of osteoradionecrosis of the jaws in oral cavity cancer patients treated with intensity-modulated radiotherapy: a systematic review and meta-analysis.

OBJECTIVE: A systematic review with meta-analysis was conducted to define the incidence of osteoradionecrosis (ORN) in patients with oral cavity cancer (OCC) treated with intensity-modulated radiotherapy (IMRT), and to identify the risk factors influencing its development. STUDY DESIGN: Six databases were searched systematically. A meta-analysis was performed to determine overall, spontaneous, and dental extraction-attributed incidences of ORN. The Grading of Recommendations Assessment, Development, and Evaluation tool evaluated evidence certainty. RESULTS: Out of 11 eligible studies, 6 underwent meta-analysis for the overall aggregated ORN incidence in OCC patients receiving IMRT, resulting in an incidence rate of 8% (95% CI: 6%-11%). Regarding development reasons, 2 studies were assessed, revealing an incidence of 36% (95% CI: 1%-98%) for spontaneous ORN, and 17% (95% CI: 5%-44%) ensued from dental extraction exclusively pre-RT. All rates had very low certainty of evidence. Factors significantly correlated with ORN development included postoperative RT use (78%), employment of therapeutic doses above 50 Gy, and mandibular involvement (80.5%). CONCLUSION: The findings suggest that IMRT alone is not sufficient to decrease ORN rates in OCC patients, underscoring the importance of precisely identifying the involved risk factors. However, further detailed primary studies will be necessary.

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.

Risk factors associated with the development of osteoradionecrosis (ORN) in Head and Neck cancer patients in Ireland: A 10-year retrospective review.

BACKGROUND AND PURPOSES: To assess osteoradionecrosis (ORN) incidence in a population of Irish Head and Neck cancer (HNC) patients, and assess precipitating factors that may contribute to ORN development to aid prevention. MATERIALS AND METHODS: Review of 1050 HNC patients attending the Dental Oncology Clinic, CUDSH between 2010 and 2021 identified 47 cases of ORN. Medical, dental and radiotherapy records of these forty-seven patients were retrospectively reviewed. Patient-, tumour-, and treatment-related variables were investigated in association with osteoradionecrosis development. Analysis conducted using SPSS, Pearson's Chi-square test (p < 0.05), and ordinal regression model. RESULTS: ORN incidence was 4.4 %. Median time from radiotherapy (RT) to ORN development was 9.5 months (range 1-98.5 months). ORN development within the mandibular surgical site was significant (p <.001), presenting at a higher Notani grade (p =.002), in mid-mandibular body region (p =.028), at radiation doses ≥ 60 Gy (p =.035), due to induced causes (p =.029), and without resolution (p =.019). CONCLUSION: This is the first retrospective study of ORN in HNC patients in Ireland over 10-year period. ORN incidence was extremely low (4.4%). As patients reported high smoking/alcohol use and poor dental attendance pre-diagnosis, this suggests intensive dental intervention pre/post-diagnosis contributed to low ORN rates. Mandibular surgery pre-RT increased risk of developing ORN at the surgical site. Therefore, we recommend future treatment planning should contour the surgical site, designating it an organ at risk (OAR), assigning a dose constraint, where oncologically possible, with emphasis on reducing the hot-spot to this region; findings reinforce importance of life-long expert dental care to reduce ORN incidence.

Retrospective study evaluating dental side effects of radiotherapy in patients treated for head and neck cancer.

INTRODUCTION: Head and neck cancer squamous cell carcinoma (HNSCC) is the seventh most common cancer worldwide with around 600,000 new diagnosis each year. Nowadays, in locally advanced disease, radiotherapy (RT) play an important role, this with or without chemotherapy in organ preservation strategies. More specific for early stage localized disease, RT (or surgery) seems to give similar results on locoregional control (LRC) and choice is made according to the organ preservation issue. Despite the fact that technical improvements have been made to optimize the radiation dose delivery and minimize the normal tissue toxicity, RT is associated with potential early and late toxicities. Osteoradionecrosis of the jaw (ORNJ), especially seen after teeth extraction, is one of the associated toxicities and can significantly impair the patient's quality of life. Because of the fear of developing ORNJ, one is very reluctant to extract or place a dental implant post-radiotherapy, especially in high irradiation dose zones (>40 Gy). Hence, it is important to define teeth at risk of future extraction before initiating RT and to handle those in high-risk irradiation zones. In order to optimise extractions, we created a predictive model of the expected irradiation dose, and thus the need for extraction, to the teeth bearing bones. The aim of this study is to validate our model and to define the potential relationship between the radiation dose received by each tooth and the dental complications observed. MATERIAL AND METHODS: Between March 2012 and March 2018, patients with HNSCC treated by intensity modulated RT were retrospectively analysed. The mean irradiation dose for each tooth was generated on the administered treatment plan by contouring each tooth separately on each dosimetric scan section using dedicated software (Eclipse, Varian). In order to validate our predictive model, we compared the actual generated/administered teeth irradiation doses with the irradiation doses predicted by our model. RESULTS: Our predictive model was accurate in 69.6% of the cases. In 12.5% of cases the predicted dose was higher than the calculated dose and lower in 17,8% of the cases. A correct- or over-estimation (is the latter being clinically less worrying than an underestimated dose) was achieved in 82% of cases. For the 18% of cases underfitting, the mean margin of error was 5.7 Gy. No statistically significant association was found between the development of caries and doses to the teeth, doses to the parotid glands or dental hygiene. However, a significant association between dental irradiation at more than 40 Gy and the occurrence of dental fractures (p = 0.0002) were demonstrated. CONCLUSIONS: Our predictive model seems to be 82% accurate for dose prediction, hence might be helpful for optimizing/minimizing prophylactic extractions. Indeed, following our model, professionals could decide not to extract damaged teeth in areas not at risk of ORNJ, lowering morbidity during and after RT. Contrary to the literature, no relationship was found between the occurrence of dental caries and parotid irradiation and the patient's oral hygiene. However, for the first time, a highly significant correlation between the occurrence of dental fracture and dental irradiation at more than 40 Gy was observed.

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.

Osteoradionecrosis - an old problem with new consequences.

PURPOSE OF REVIEW: Osteoradionecrosis (ORN) is a devasting complication of radiation therapy (RT), especially in head and neck cancers (HNC), and is still poorly understood. The aim of this review is to report its incidence and consider the risk factors associated with ORN to highlight prevention strategies to decrease its incidence. RECENT FINDINGS: The average incidence of ORN is between 2% and 23%, with incidence decreasing in more recent years with the introduction of modern RT technology and better oral health care. Smoking, diabetes mellitus, oropharyngeal and oral cavity cancers, pre- and post-RT dental extractions and a total radiation dose of over 60 Gy were all identified as risk factors for ORN. In prevention, strategies were mainly structured around minimising risk factors or targeting possible mechanisms of ORN's pathophysiology. SUMMARY: At present, the controversy surrounding the risk factors and pathogenesis of ORN makes it difficult to establish a set of prevention guidelines for its incidence. In order to achieve this, more research examining its aetiology must be conducted as well as a universal staging system within which ORN may be classified.

Osteonecrosis maxilar asociada a bifosfonatos: enigma contemporáneo / Biphosphonate-related osteonecrosis of the jaw: nowadays enigma

Los bifosfonatos fueron sintetizados en el siglo XIX por químicos alemanes que buscaban prevenir el depósito industrial de carbonato de calcio en sus chimeneas. Más tarde se observó la gran afinidad de la droga con el tejido óseo y que además inhibía la conversión de fosfato de calcio amorfo a hidroxiapatita (HA), lo cual reducía la velocidad de disolución de los cristales óseos. Se realizó una revisión de la literatura referida a osteonecrosis maxilar asociada a bifosfonatos utilizando las palabras clave. La búsqueda en la base de datos PubMed y LILACS incluyó las publicaciones de los años 2006-2011. Estos compuestos sintéticos son utilizados hace más de tres décadas para el tratamiento de desórdenes esqueletales: osteoporosis, enfermedad de Paget, hipercalcemia asociada a mieloma múltiple y metástasis óseas propias de cáncer de próstata y mama, osteogénesis imperfecta y displasia fibrosa. Recientemente se han descrito algunos casos de osteonecrosis maxilar a causa de tratamiento crónico con bifosfonatos a altas dosis en la prescripción de dichas drogas utilizadas como terapéutica oncológica.

A retrospective study of trauma-associated oral and maxillofacial lesions in a population from southern Taiwan

OBJECTIVE: The aim of this retrospective analysis was to determine the age, gender, frequency and distribution of trauma-associated hard tissue and soft tissue lesions of the oral and maxillofacial region in a population from southern Taiwan. PATIENTS AND METHODS: Approximately 10 percent of the 27,995 biopsy records of patients with history of trauma resulting in lesions who were treated at our institution between 1991 and 2006 were examined for this study. RESULTS: In the included records, there were 2,762 soft tissue and 26 hard tissue lesions. Mucocele was the most frequent trauma-associated soft tissue lesion (955 cases). The youngest patients were those who presented with mucocele (mean age = 27.3 years), while the oldest patients were those with peripheral giant cell granuloma (58 years). The lower lip was the most frequent site of occurrence of mucocele (676, 64.5 percent) and was also the predominant site of occurrence of all soft tissue lesions (815, 29.5 percent), followed by the buccal mucosa (654, 23.4 percent) and the tongue (392, 14.2 percent). Trauma-associated hard tissue lesions included only osteoradionecrosis (24 cases) and traumatic bone cysts (2 cases). CONCLUSION: As little data of this nature have been reported from populations of Asian developing countries, the findings of this retrospective analysis is valuable for epidemiological documentation of type of traumatic oral lesions as well as for informing the professionals and the layman about the importance of this category of oral lesions.

Osteorradionecrose de cravícula / Osteoradionecrosis of clavicle

Resumo: A osterradionecrose após radioterapia para as neoplasias de cabeça e pescoço tem incidência variável. A mandíbula é o osso mais frequentemente afetado, sendo a osterradiocrese de clavícula uma rara ocorrência. O presente trabalho apresenta três pacientes com osteorradionecrose de clavícula subsequente a tratamento cirúrgico e radioterapia para neoplasias de cabeça e pescoço. Os três pacientes foram submetidos a esvaziamento cervical, rotaçäo de retalho miocutâneo de músculo peitoral maior e irradiaçäo dos leitos tumorais com campos se estendendo às cadeias e fossas supraclaviculares. Desenvolveram a osteorradionecrose após períodos de noves meses, três anos e sete anos após a radioterapia. Enfatizamos os principais mecanismos envolvidos na produçäo da necrose óssea, os fatores comumente implicados no seu desencadeamento, bem como assinalamos as formas terapêuticas. Embora a osterradionecrose clavicluar apresente baixa incidência, ela deve ser caracterizada em pacientes tratados com grandes ressecçöes cirúrgicas e rotaçöes de retalhos muicutâneos.

Osteorradionecrose de mandíbula em pacientes com câncer de boca / Osteoradionecrosis of the mandible in patients with oral cancer

Os autores estudam 613 pacientes portadores de carcinoma espinocelular de boca, submetidos à radioterapia exclusiva ou em associaçäo com cirurgia, atendidos no período de janeiro de 1980 a dezembro de 1989, no Serviço de Cirurgia de Cabeça e Pescoço do Complexo Hospitalar Heliópolis, Brasil. No cálculo da prevalência de osteorradionecrose, foram avaliadas a extensäo da lesäo primária (T), e influência das cirurgias que envolviam ou näo o tecido ósseo, a dose de irradiaçäo e a idade. Encontramos uma prevalência de 31,5 por cento de osteorradionecrose, sendo a dose de radiaçäo o fator de maior influência para o desencadeamento desta complicaçäo. As lesöes classificadas como T1 tiveram uma prevalência significativamente menor que as lesöes avançadas. A extensäo da cirurgia näo foi importante, sendo indiferente se houve ressecçäo ou näo de parte da mandíbula. A idade se mostrou estatisticamente correlacionada à ocorrência de osteorradionecrose, sendo que os pacientes com menos de 60 anos tiveram uma prevalência de 65,3 por cento e, aqueles com mais de 60 anos, apresentaram 73,5 por cento.