Identifying MRONJ-affected bone with digital fusion of functional imaging (FI) and cone-beam computed tomography (CBCT): case reports and hypothesis

Surgical margins in head and neck squamous cell carcinoma: A narrative review

Head and neck squamous cell carcinoma (HNSCC), a prevalent and frequently recurring malignancy, often necessitates surgical intervention. The surgical margin (SM) plays a pivotal role in determining the postoperative treatment strategy and prognostic evaluation of HNSCC. Nonetheless, the process of clinical appraisal and assessment of the SMs remains a complex and indeterminate endeavor, thereby leading to potential difficulties for surgeons in defining the extent of resection. In this regard, we undertake a comprehensive review of the suggested surgical distance in varying circumstances, diverse methods of margin evaluation, and the delicate balance that must be maintained between tissue resection and preservation in head and neck surgical procedures. This review is intended to provide surgeons with pragmatic guidance in selecting the most suitable resection techniques, and in improving patients' quality of life by achieving optimal functional and aesthetic restoration.

Medication-related osteonecrosis of the jaw without osteolysis on computed tomography: a retrospective and observational study

Medication-related osteonecrosis of the jaw (MRONJ) is a refractory osteonecrosis caused by antiresorptive agents such as bisphosphonate and denosumab (DMB). In MRONJ surgery, computed tomography (CT) is generally used to determine the extent of bone resection. However, in some recent MRONJ cases, no abnormal findings were detected on CT. Therefore, we aimed to clarify the characteristics of MRONJ without osteolysis. This retrospective and observational study included 18 patients diagnosed with MRONJ between October 2020 and October 2022 at Department of Dentistry and Oral Surgery, Kansai Medical University Medical Center. In four of 18 patients with MRONJ, no abnormal findings such as osteolysis, separation of sequestrum, and periosteal reaction were observed on CT images at the first visit. All four patients with non-osteolytic MRONJ had malignant tumors and received high-dose DMB, and in the four patients there were no preceding dental infections such as apical lesions or periodontal disease and the trigger of MRONJ was unknown. Surgery was performed in three of the four patients. The extent of bone resection was determined using magnetic resonance imaging and intraoperative gross findings. In the future, it is necessary to establish a method for diagnosing non osteolytic MRONJ and determining the extent of bone resection.

Quantitative indices for cone-beam CT assessment of Medication-Related Osteonecrosis of the Jaw - a scoping review

Objectives

It is not unusual for Medication-related osteonecrosis of the jaw (MRONJ) lesions that have similar clinical presentation and staging to have dissimilar radiographic extent of disease. The aim of this review was to explore the published scientific literature for quantitative indices that describe the cone-beam computerized tomography (CBCT) radiographic features of MRONJ lesions and assess their clinical utility.

Method and Materials

A scoping review of the literature was performed to identify quantitative indices developed to describe the CBCT radiographic features of MRONJ lesions. Five electronic databases were included in the review: PubMed, Scopus, Web of Science, Trip medical database, and Cochrane Library. Articles published from the year 2003 onward were included in the review.

Results

367 articles were initially included in the review. 39 abstracts were screened for full-text assessment. The scoping review yielded 12 full length articles with169 cases reported. The Composite Radiographic Index score (CRI score) was identified as the most meaningful index in published literature that attempted to quantify qualitative radiographic changes (Walton, Grogan et al. 2019). However, lesions with similar CRI scores that corresponded to intermediate severity (3-5) may be very dissimilar radiographically in both nature and extent of radiographic changes, undercutting its clinical value.

Conclusion

The CRI index score was the only relevant index for cross-sectional (one-time) assessment of established MRONJ lesions (non-stage 0). This scoping review yielded several critical questions regarding the clinical significance and prognostic implications of various radiographic changes in MRONJ, thereby identifying focus areas for future research.

Do various imaging modalities provide potential early detection and diagnosis of medication-related osteonecrosis of the jaw? A review

OBJECTIVE

Patients with medication-related osteonecrosis of the jaw (MRONJ) often visit their dentists at advanced stages and subsequently require treatments that greatly affect quality of life. Currently, no clear diagnostic criteria exist to assess MRONJ, and the definitive diagnosis solely relies on clinical bone exposure. This ambiguity leads to a diagnostic delay, complications, and unnecessary burden. This article aims to identify imaging modalities' usage and findings of MRONJ to provide possible approaches for early detection.

METHODS

Literature searches were conducted using PubMed, Web of Science, Scopus, and Cochrane Library to review all diagnostic imaging modalities for MRONJ.

RESULTS

Panoramic radiography offers a fundamental understanding of the lesions. Imaging findings were comparable between non-exposed and exposed MRONJ, showing osteolysis, osteosclerosis, and thickened lamina dura. Mandibular cortex index Class II could be a potential early MRONJ indicator. While three-dimensional modalities, CT and CBCT, were able to show more features unique to MRONJ such as a solid type periosteal reaction, buccal predominance of cortical perforation, and bone-within-bone appearance. MRI signal intensities of vital bones are hypointense on T₁WI and hyperintense on T₂WI and STIR when necrotic bone shows hypointensity on all T₁WI, T₂WI, and STIR. Functional imaging is the most sensitive method but is usually performed in metastasis detection rather than being a diagnostic tool for early MRONJ.

CONCLUSION

Currently, MRONJ-specific imaging features cannot be firmly established. However, the current data are valuable as it may lead to a more efficient diagnostic procedure along with a more suitable selection of imaging modalities.

Medication-Related Osteonecrosis of Jaws (MRONJ) Prevention and Diagnosis: Italian Consensus Update 2020

The Medication-Related Osteonecrosis of Jaws (MRONJ) diagnosis process and its prevention play a role of great and rising importance, not only on the Quality of Life (QoL) of patients, but also on the decision-making process by the majority of dentists and oral surgeons involved in MRONJ prevention (primary and secondary). The present paper reports the update of the conclusions from the Consensus Conference-held at the Symposium of the Italian Society of Oral Pathology and Medicine (SIPMO) (20 October 2018, Ancona, Italy)-after the newest recommendations (2020) on MRONJ were published by two scientific societies (Italian Societies of Maxillofacial Surgery and Oral Pathology and Medicine, SICMF and SIPMO), written on the inputs of the experts of the Italian Allied Committee on ONJ (IAC-ONJ). The conference focused on the topic of MRONJ, and in particular on the common practices at risk of inappropriateness in MRONJ diagnosis and therapy, as well as on MRONJ prevention and the dental management of patients at risk of MRONJ. It is a matter of cancer and osteometabolic patients that are at risk since being exposed to several drugs with antiresorptive (i.e., bisphosphonates and denosumab) or, more recently, antiangiogenic activities. At the same time, the Conference traced for dentists and oral surgeons some easy applicable indications and procedures to reduce MRONJ onset risk and to diagnose it early. Continuous updating on these issues, so important for the patient community, is recommended.

Medication-Related Osteonecrosis of the Jaws: Two Center Retrospective Cohort Studies

This retrospective cohort study aims to describe characteristics of patients with MRONJ, to identify factors associated with MRONJ development, and to examine variables associated with favourable outcome. Totally 32 patients were followed and observed: 21 females and 11 males, in the age range 35-84 in the period from 2009 to 2018. Clinical, radiological examination (Orthopantomograph and CBCT) and biopsy were performed in order to achieve diagnosis. Demographic and clinical variables were taken into consideration: sex, age, primary disease, medication type, mode of delivery, anatomic location, drug treatment duration, timing of tooth extraction, chemotherapy, presence of bone metastasis, aetiology of MRONJ, disease stage, and treatment modality. MRONJ developed under osteoporosis and malignant disease in 11 and 21 patients, respectively. MRONJ development was triggered by tooth extraction or trauma in 30 out of 32 cases, whereas the two patients developed MRONJ spontaneously. Stages I, II, and III were confirmed in 5 (16%), 18 (58%), and 9 (28%) patients, respectively. Mandible was affected in 23 (72%) patients. MRONJ was treated in our department by conservative and surgical modality. In this study we found that 65% of all patients were classified in the cured/improvement group and 35% in the stable/progression group. The female gender, osteoporosis as primary disease, oral regime intake, shorter period on BPs, earlier stage of disease, and specific anatomic localisation (frontal and premolar maxilla) were factors associated with better response to therapy and favourable clinical outcome. Comprehensive treatment protocol and further randomized studies are necessary for further improvements.

Investigation of dental cone-beam CT pixel data and a modified method for conversion to Hounsfield unit (HU)

OBJECTIVES

To investigate the relationship in dental cone-beam CT (CBCT) between the manufacturer-reported image pixel data and a modified conversion to CT number densities in Hounsfield unit (HU).

METHODS

A standardized CT phantom was imaged using typical clinical parameters on CBCT from three manufacturers (Carestream 9300^®, Carestream Health, Rochester, NY; J Morita 3D Accutomo^®, J. Morita Mfg. Corp., Kyoto, Japan; and Planmeca Promax 3D^®, Planmeca Helsinki, OY, Finland). Reconstructed axial slices were evaluated using regions of interest to ascertain the mean pixel value in five materials in the phantom. The Digital Imaging and Communications in Medicine data were also evaluated to determine if raw pixel data had been adjusted during the image reconstruction. A modified version of the existing manual HU conversion technique was applied, and the resultant slope and y-intercept were used to scale the pixel values ultimately to HU for all images.

RESULTS

The DICOM header data show that a modified rescale y-intercept was applied to both the Carestream and Planmeca image data yielding manufacturer-produced results in HU. The Morita pixel data were unmodified and report in shades of grey or grey values (GV). The Carestream manufacturer-derived HU measurements showed good correlation in air (-1000 HU), but all other materials ranged from 2.6 to 13.5 σ from the specified phantom value. Results in the modified conversion technique images fell within 1.0-2.4 σ from the specified phantom values.

CONCLUSIONS

While more studies are needed to test for regularity, this study suggests that our modified technique could be a means of getting more accurate quantitative data from dental CBCTs.