Assessment of Thermal Osteonecrosis during Bone Drilling Using a Three-Dimensional Finite Element Model.

Bone drilling is a common procedure used to create pilot holes for inserting screws to secure implants for fracture fixation. However, this process can increase bone temperature and the excessive heat can lead to cell death and thermal osteonecrosis, potentially causing early fixation failure or complications. We applied a three-dimensional dynamic elastoplastic finite element model to evaluate the propagation and distribution of heat during bone drilling and assess the thermally affected zone (TAZ) that may lead to thermal necrosis. This model investigates the parameters influencing bone temperature during bone drilling, including drill diameter, rotational speed, feed force, and predrilled hole. The results indicate that our FE model is sufficiently accurate in predicting the temperature rise effect during bone drilling. The maximum temperature decreases exponentially with radial distance. When the feed forces are 40 and 60 N, the maximum temperature does not exceed 45 °C. However, with feed forces of 10 and 20 N, both the maximum temperatures exceed 45 °C within a radial distance of 0.2 mm, indicating a high-risk zone for potential thermal osteonecrosis. With the two-stage drilling procedure, where a 2.5 mm pilot hole is predrilled, the maximum temperature can be reduced by 14 °C. This suggests that higher feed force and rotational speed and/or using a two-stage drilling process could mitigate bone temperature elevation and reduce the risk of thermal osteonecrosis during bone drilling.

The use of hyperbaric oxygen for avascular necrosis of the femoral head and femoral condyle: a single centre's experience over 30 years.

Introduction: Avascular necrosis (AVN) is a rare progressive degenerative disease leading to bone and joint destruction. Patients often require surgical intervention. Femoral AVN is the most common anatomical location. Hyperbaric oxygen treatment (HBOT) has been shown to be effective in AVN. We present data collected from one centre over a 30-year period and compare the results with other published data. Methods: A retrospective chart review of all patients receiving HBOT for AVN at Fremantle and Fiona Stanley Hospitals since 1989 was performed. The primary outcome was radiological appearance using the Steinberg score, with secondary outcomes being subjective improvement, the need for joint replacement surgery and rates of complications. Results: Twenty-one joints in 14 patients (14 femoral heads and seven femoral condyles) were treated with HBOT since 1989. Two patients were excluded. Within the femoral head group, nine of the 14 joints (64%) had stable or improved magnetic resonance imaging (MRI) scans post treatment and at six months (minimum); 10 joints (71%) had good outcomes subjectively, three joints required surgical intervention, and three patients developed mild aural barotrauma. Within the femoral condyle group, all five joints had stable or improved post-treatment MRI scans (four had visible improvement in oedema and/or chondral stability), four joints reported good outcomes subjectively, none of the patients required surgical intervention (follow-up > six months). Conclusions: This single centre retrospective study observed prevention of disease progression in femoral AVN with the use of HBOT, comparable to other published studies. This adds to the body of evidence that HBOT may have a significant role in the treatment of femoral AVN.

Levels of small extracellular vesicles in patients treated with hyperbaric oxygenation.

Introduction: Hyperbaric oxygen (HBO2) therapy involves the inhalation of pure oxygen in a pressure chamber under increased ambient pressure. Recent research indicates that circulating small extracellular vesicles (sEVs) play important roles in human physiology and pathology. Therefore, the objective of this pilot study was to monitor the impact of HBO2 therapy on the levels of circulating sEVs in the serum of patients with necrotizing soft-tissue infections (NSTI), aseptic bone necrosis (ABN) or idiopathic sudden sensory neural hearing loss (ISSNHL). Material and methods: Serum-derived sEVs were isolated and quantified in 80 patients before and after HBO2 therapy applied for NSTI, ISSNHL and ABN patients as well as in normal controls who received neither HBO2 therapy nor steroids. Results: We observed a significant increase of circulating sEVs in patients with ISSNHL after HBO2 therapy (p < 0.05), as well as significantly elevated levels of sEVs after HBO2 therapy compared to patients with NSTI (p < 0.05) and ABN (p < 0.01). Conclusions: The increase in the levels of sEVs in ISSNHL may be evidence for both the intended reduction of inflammation as a result of steroid therapy and the inhibitory effect of oxidative stress induced by HBO2 therapy. Thus, sEVs released during HBO2 therapy might play an important biological role in mediating the response to therapy and might be a promising approach to gain further insights into the therapeutic efficacy of HBO2 therapy.

Micro-CT, Mechanical, and Histological Examination of the Effect of Local Adjuvants on Porcine Cortical Bone Following Intralesional Curettage of Bone Tumors.

BACKGROUND AND OBJECTIVES: Curettage is the removal of a tumor from the bone while preserving the surrounding healthy cortical bone, and is associated with higher rates of local recurrence. To lower these rates, curettage should be combined with local adjuvants, although their use is associated with damage to nearby healthy bone. OBJECTIVE: The purpose of this analysis is to determine the effect of local adjuvants on cortical porcine bone by using micro-computed tomography (micro-CT) along with histological and mechanical examination. METHODS: Local adjuvants were applied to porcine specimens under defined conditions. To assess changes in bone mineral density (BMD), a micro-CT scan was used. The pixel gray values of the volume of interest (VOI) were evaluated per specimen and converted to BMD values. The Vickers hardness test was employed to assess bone hardness (HV). The depth of necrosis was measured histologically using hematoxylin and eosin-stained tissue sections. RESULTS: A noticeable change in BMD was observed on the argon beam coagulation (ABC) sample. Comparable hardness values were measured on samples following electrocautery and ABC, and lowering of bone hardness was obtained in the case of liquid nitrogen. Extensive induced depth of necrosis was registered in the specimen treated with liquid nitrogen. CONCLUSION: This study determined the effect of local adjuvants on cortical bone by using micro-CT along with histological and mechanical examination. Phenolization and liquid nitrogen application caused a decrease in bone hardness. The bone density was affected in the range of single-digit percentage values. Liquid nitrogen induced extensive depth of necrosis with a wide variance of values.

Early detection of aseptic bone necrosis post-cranioplasty: A retrospective CT analysis using Hounsfield units.

This study examined the efficacy of computed tomography (CT)-based Hounsfield units (HU) as early predictors of aseptic bone necrosis, a serious post-cranioplasty complication after autologous cranioplasty. In total, 100 patients who underwent decompressive craniectomy and subsequent autologous cranioplasty were included. The radiodensity of the bone flap was evaluated in HU from CT scans at five follow-up timepoints. HU thresholds were established to predict the development of aseptic bone necrosis. HU demonstrated a declining trend throughout the follow-up period in all patients. Necrosis type I patients showed significant differences at all timepoints from 3 months post-procedure onwards, while necrosis type II patients displayed a significant decline in HU at every follow-up. Optimal thresholds with cut-off A (91.23% of initial HU) and cut-off B (78.73% of initial HU) were established to predict the occurrence of bone necrosis and the need for artificial bone replacement, respectively. Our findings demonstrated the utility of CT-based HU measurements as a simple, non-invasive tool for the early prediction of aseptic bone necrosis following autologous cranioplasty. By delineating specific HU thresholds, our study offers a valuable guide for orchestrating timely follow-ups and advising patients on the necessity of proactive interventions.

Diffuse B-Cell Lymphoma of the Mandible Disguised as Acute Osteomyelitis.

Background: Primary bone lymphoma (PBL) is a rare form of extra nodal non-Hodgkin's lymphoma (NHL). Case description: We describe a 39-year-old-male with no medical history who presented with unilateral facial swelling following a tooth extraction. Initial diagnoses after various presentations over the course of three weeks, based on inflammatory and infectious aetiologies. However, the patient was ultimately diagnosed with diffuse large B-cell lymphoma. Discussion: Symptoms of PBL are very similar to inflammatory and infectious diseases of the bone, such as osteomyelitis or osteonecrosis. Clinical features of PBL involving the head and neck include persistent jaw pain, tooth mobility secondary to extensive destruction of bone, and in advanced cases, lip numbness and swelling. On examination it may present as an exposed necrotic bone with surrounding soft tissue oedema. Misdiagnosis of these lesions as an infectious or inflammatory aetiology may lead to an unnecessary delay in lymphoma treatment, and subsequently worsen the prognosis if caught at a later stage. Therefore, any concerning lesion, especially in the oral cavity, must be subjected to early histopathological evaluation to differentiate PBL from osteomyelitis and/or osteonecrosis. Conclusion: This case report highlights the importance of an early histopathological evaluation to prevent delay in the diagnosis of primary bone lymphomas. LEARNING POINTS: Resemblance in symptoms: Primary bone lymphoma (PBL) symptoms overlap with bone infections, necessitating careful consideration and differential diagnosis to prevent misjudgment.Head and neck manifestations: recognising PBL's signs in the head and neck region, such as jaw pain and bone destruction, aids in timely identification and treatment.Timely biopsy significance: swift histopathological assessment for suspicious lesions is critical to avoid delays in diagnosing primary bone lymphomas.

Management of frontal sinus fractures requiring surgical intervention: An analysis of a case series.

<b><br>Introduction:</b> Isolated frontal bone fractures constitute 5-15% of traumatic facial fractures cases, with frontal sinus fractures categorized into anterior wall, posterior wall, or complex fractures. The approach is tailored to fracture type and bone fragment displacement. This paper presents the summary of surgical management in patients with isolated and complex fractures of the anterior wall of the frontal sinus.</br> <b><br>Material and Methods:</b> Five patients with different frontal sinus fractures were treated surgically. The same management protocol - diagnosis and surgical intervention was implemented in all cases The retrospective analysis included fracture assessment, surgical approach, and long-term outcomes evaluation.</br> <b><br>Results:</b> The most common cause of fractures was falls, while two complex fractures involved the anterior and posterior walls. External approach, bone fragment removal, endoscopy, and external stabilization were employed in all cases. One patent required delayed revision surgery due to retaining metallic foreign body. Follow-up radiological examinations showed proper healing and cosmetic outcomes were satisfactory in all of the cases.</br> <b><br>Conclusion:</b> Surgical management of isolated fractures of the frontal sinus anterior wall, involving bone fragment removal, realignment, and endoscopy, yielded satisfactory functional and cosmetic outcomes without internal or external stabilization. Long-term monitoring and symptom assessment are crucial, especially in cases with penetrating injuries and foreign body risk.</br>.

[Infectious, pathologic humeral fracture in a patient with sickle cell disease-A rare case?] / Infizierte, pathologische Humerusfraktur bei Sichelzellanämie ­ noch ein Einzelfall?

The vaso-occlusive crises of sickle cell disease are accompanied by bone necrosis, which favors endogenous bacterial colonization and thus osteomyelitis. This poses a major challenge for eradication and fracture management.A 22-year-old patient with sickle cell disease sustained a multifragmentary, humeral shaft fracture. During surgical management, pus drained from the fracture site and further diagnostic work-up revealed osteomyelitis with evidence of Klebsiella aerogenes. Septicemia due to Klebsiella aerogenes had been treated 5 months prior to the accident, which occured because of a vaso-occlusive crisis. This is associated with clustered bone necrosis and endogenous germ colonization. Eradication of the germs and fracture care become a challenge. Repeated surgical procedures with segmental transfer can be a successful treatment option.

The use of advanced-platelet rich fibrin (A-PRF) in the management of medication-related osteonecrosis of the jaw (MRONJ): A case report.

Medication-related osteonecrosis of the jaws (MRONJ) is a serious debilitating disease resulting from long-term treatment with Antiresorptive drugs such as Bisphosphonates or Denosumab, which significantly affects patients' quality of life. A 43-year-old female patient with stage 4 breast cancer and treated with Zoledronic Acid for bone metastases was referred to the Department of Oral Medicine at the Faculty of Dentistry, Damascus University. The main complaint was pain in the right maxilla. Intraoral examination showed an exposure of necrotic bone in the right maxillary region with presence of purulent exudate. The treatment plan was discussed with the patient. Treatment included resection of all necrotic bone and application of Advanced platelet-rich fibrin (A-PRF) clots and membranes. Follow-up and outcome were conducted by clinical measures to assess healing and recurrence (6-month follow-up). Topical treatment with A-PRF demonstrated a reduction in pain and resulted in complete wound healing within 30 days. A-PRF stimulates the release of growth factors and chemotaxis involved in tissue repair mechanisms. This method seemed to be effective in the treatment of MRONJ.

Reconstruction of Moderately and Severely Atrophic Scalp-A Multicentric Experience in Surgical Treatment of Patients Irradiated for Tinea Capitis in Childhood and Surgical Algorithm.

Background and Objectives: Before the introduction of griseofluvin, the use of X-ray radiation was the treatment of choice for tinea capitis. More than half a century later various types of tumors have been found to be associated with childhood irradiation due to tinea capitis, most commonly cancers of the head and neck, as well as brain tumors. The often unusually aggressive and recurrent nature of these tumors necessitates the need for repeated surgeries, while the atrophic skin with an impaired vascular supply due to radiation often poses an additional challenge for defect reconstruction. We present our experience in the surgical treatment of such patients. Materials and Methods: This is a retrospective cohort study. In this study, 37 patients treated for acquired defects of the scalp with a history of irradiation therapy due to tinea capitis in childhood were included in this study, 24 male and 13 female patients. The mean age at the first appointment was 60.6 ± 7.8, with the youngest included patient being 46 and the oldest being 75 years old. Patients' characteristics, surgical treatment, and complications were analyzed and a reconstructive algorithm was developed. Results: Local flaps were used for reconstruction in 34 patients, direct sutures were used in 10 patients and 20 patients received split-thickness skin grafts for coverage of both primary and secondary defects for reconstruction of flap donor sites. One regional flap and one dermal substitute covered by an autologous skin graft were also used for reconstruction. Complications occurred in 43.2% of patients and were significantly associated with the presence of comorbidities (p = 0.001), aseptic bone necrosis (p = 0.001), as well as skin atrophy in frontal, occipital, and parietal region (p = 0.001, p = 0.042 and p = 0.001, respectively). A significant correlation between major complications and moderate skin atrophy was found only in the parietal region (p = 0.026). Conclusions: Unfortunately, many protocols developed for scalp reconstruction are not applicable in the setting of severe or diffuse scalp skin atrophy associated with high tumor recurrence rate and radiation-induced vascular impairment, such as in tinea capitis patients in Serbia. An algorithm has been developed based on the authors' experience in managing these patients.

COVID-19-Related Bilateral Avascular Necrosis of the Femoral Head.

Osteonecrosis is a pathologic process that involves focal bone infarction and death of bone tissue caused by trauma, infections, autoimmune conditions, and chronic steroid use; however, most cases go undiagnosed. The link between bilateral osteonecrosis and coronavirus disease 2019 (COVID-19) infections has not been fully investigated. This is the case of a 42-year-old Caucasian woman who presented to the emergency department for bilateral hip pain, which started three months prior. Initially, the pain was mild; however, her symptoms worsened, causing her to have difficulty ambulating. Co-incidentally she tested positive for COVID-19 10 days after the onset of pain. She denied any lower-extremity numbness, weakness, and loss of bowel or bladder function. X-ray of the hips showed significant sclerosis of bilateral femoral heads and acetabula, indicating avascular necrosis. She was given ketorolac injection intramuscularly for analgesia and remained in stable condition. Upon discharge, she was given a referral to orthopedic surgery for bilateral total hip arthroplasty. Atraumatic osteonecrosis of the femoral head can be caused by multiple etiologies, including exposure to medications, post-transplantation procedures, trauma, and hypercoagulable states. This condition is likely due to poor angiogenesis after an infarct, causing a domino effect of bone demineralization, trabecular thinning, and cortical collapse. A literature search demonstrated prior cases of unilateral femoral head necrosis associated with COVID-19 infection and steroid use. There have been no cases of bilateral osteonecrosis of the femoral head reported without long-term steroid use. Considering the disease severity in both hips and limited steroid use (only five days of prednisone), other common etiologies were sought and were ruled out. In our patient, the only event that was related to her initial onset of hip pain was a COVID-19 infection. We suggest a relationship between COVID-19 infection and avascular necrosis given the rapid progression of the disease. We acknowledge that this presentation of bilateral osteonecrosis is rare and warrants further investigation. More research should be performed to establish a tenable relationship between COVID-19 infection and osteonecrosis, with and without the use of steroids.

Collapse after Carpal Bone Tunneling. An Underreported Complication?

PURPOSE: To report the complication of carpal bone tunnel collapse in scapholunate reconstruction. METHODS: The authors present six cases of carpal collapse or bone necrosis after bone tunneling for ligamentous reconstruction, three in the scaphoid bone and three in the lunate. RESULTS: All six cases were secondary to ligament reconstruction for chronic scapholunate dissociations, none of which had preoperative structural scaphoid or lunate deformities. CONCLUSIONS: Although the incidence of this occurrence is unknown, the consequences could be substantial; therefore, patients should be warned of this possibility when discussing complications of ligament reconstruction for chronic scapholunate instability requiring the creation of a bone tunnel. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic V.

Risk comparison of osteonecrosis of the jaw in osteoporotic patients treated with bisphosphonates vs. denosumab: a multi-institutional retrospective cohort study in Taiwan.

In this multi-institutional retrospective cohort study, we compared the long-term risk of osteonecrosis of the jaw following the use of denosumab vs. bisphosphonates in osteoporotic patients. After 2-year use, the likelihood of osteonecrosis of the jaw is lower with denosumab compared to bisphosphonates, and the difference increases with time. PURPOSE: To compare the long-term risk of osteonecrosis of the jaw (ONJ) between osteoporotic patients treated with bisphosphonates (BPs) and denosumab. METHODS: This multi-institutional retrospective cohort study included patients aged > 40 years with osteoporosis between January 2010 and December 2018. Patients who met the eligibility criteria were divided into BPs and denosumab groups by propensity score matching (PSM). The risk of ONJ of denosumab vs. BPs was estimated using a Cox proportional hazards model and was described by the cumulative incidence rate using the Kaplan-Meier method. RESULTS: A total of 84,102 patients with osteoporosis were enrolled, among whom, 8962 were eligible for inclusion based on their first-line drug use (denosumab, n = 3,823; BPs, n = 5,139). Following PCM matching (1:1), the BPs and denosumab groups included 3665 patients each. The incidence density of ONJ in the denosumab and BPs matching groups was 1.47 vs. 2.49 events (per 1000 person-years), respectively. The hazard ratio of ONJ in the denosumab vs. BPs group was estimated as 0.581 (95% confidence interval: 0.33-1.04, p = 0.07). The cumulative incidence rates of ONJ in both groups were similar for the first and second years of drug use (p = 0.062), but significantly different from the third year onwards (p = 0.022). The severity of ONJ was not significantly different between the two groups. CONCLUSION: In osteoporotic patients, after 2 years of use, the likelihood of ONJ being induced by denosumab is lower than that of BPs, and the difference increases with time.

Vascularized Bone Grafts from the Lateral Femoral Condyle for the Treatment of Avascular Lunate Necrosis (Kienböck's).

Background: Avascular necrosis of the lunate (Kienböck's disease) is rare and one of the main causes of progressive painful arthritis, requiring surgical intervention. Various approaches have shown benefits in treating Kienbock's disease but with limitations. The article aims to analyze the functional outcome using lateral femoral condyle free vascularized bone grafts (VBGs) as the first choice of treatment for Kienböck`s. Materials and methods: This was a retrospective analysis of 31 patients with Kienbock's who had microsurgical revascularization or reconstruction of the lunate between 2016 and 2021 using either corticocancellous or osteochondral VBGs from the lateral femoral condyle. The characteristics of lunate necrosis, choice of VBG and postoperative functional outcome were reviewed. Results: Corticocancellous VBGs were used in 20 patients (64.5%), while osteochondral VBGs in 11 patients (35.4%). The lunate was reconstructed in 11 patients, revascularized in 19 patients, and one patient received augmentation of a luno-capitate arthrodesis with a corticocancellous graft. We noted postoperative irritation of the median nerve (n = 3) and screw loosening requiring removal (n = 1) as minor complications. All patients had complete graft healing at eight-month follow-up and acceptable functional outcomes. Conclusions: Free VBG from the lateral femoral condyle represent a reliable method of lunate revascularisation or reconstruction in advanced Kienböck's. Their main advantages are the constant vascular anatomy, straightforward graft harvesting technique and possibility to harvest several graft types according to the requirements at the donor site. Postoperatively, the patients become pain-free and have an acceptable functional outcome.

Management of Medication-Related Osteonecrosis of the Jaw with Photobiomodulation and Minimal Surgical Intervention.

Medication-related osteonecrosis of the jaw (MRONJ) is a relatively common pathology occurring in around 5% of patients taking bisphosphate and other antiresorptive or anti-angiogenic medications. Despite the efforts, as of today there is still no consensus on its management. In this case report, the successful management of stage II MRONJ was performed for an eighty-three-year-old female patient suffering from pain and alteration in her normal oral functions (swallowing and phonation). The treatment consisted of three sessions of photobiomodulation therapy (PBM), followed by minimal surgical intervention and three other sessions of PBM. PBM was applied on the sites of osteonecrosis with the follow parameters: 4 J/cm2; a power of 50 mW; 8 mm applicator diameter; a continuous contact mode. Irradiation was performed on three points, including the vestibular, occlusal and lingual parts of each of the bone exposure areas. Each point was irradiated for 40 s, and, in total, nine points were made per session, and nine sessions were conducted. To assess the pain, a visual analogue scale was used in which zero represented no pain at all and ten represented the greatest pain. At the first session and before any intervention, the patient stated that her pain was 8 out of 10. At the end of the treatment, a significant reduction in VAS was noted (2/10) and, clinically, a healing of the soft tissue in the previously exposed bone was observed. This case report suggests that the combination of PBM with surgical intervention is promising in the management of MRONJ.

Pancreatitis, panniculitis and polyarthralgia syndrome: A rare complication of pancreatic pathology.

Pancreatitis, panniculitis, and polyarthralgia (PPP) syndrome is a rare complication of chronic pancreatitis and occurs due to leakage of pancreatic enzymes in the systemic vasculature. This enzyme leakage leads to multiple manifestations such as polyarthralgia, panniculitis, and bone necrosis due to tissue autodigestion.The inciting pancreatic pathology may be masked, and the presentation may be due to one of the systemic consequences of enzyme leakage, which can present as a diagnostic challenge for clinicians. Here we present a patient who presented with nodular lesions and bone necrosis, and was found to have PPP syndrome. Therefore, a proper understanding of pathophysiology and radiology findings can help with prompt diagnosis and early exploration of management options.

An Explorative Study of the Causal Pathogenesis of Green Liver Discoloration in Organically Reared Female Bronze Turkeys (Meleagris gallopavo) Considering the Infectious Risk Factors.

A recent study revealed that organically raised Bronze turkeys showed a high prevalence of green liver discoloration. This alteration is commonly associated with the Turkey Osteomyelitis Complex and potentially caused by opportunistic bacteria. Therefore, 360 organically fattened Bronze turkeys were examined post-mortem throughout two fattening trials with two examinations each to determine possible infectious risk factors and reduce disease prevalence. Clinical and pathoanatomical examinations were performed on every hen. Histopathological, bacteriological, parasitological, and virological examinations were performed on at least six hens without and, if applicable, six hens with green livers on each examination date. Overall, 9.0% of all hens had a green liver without a correlation with bacterial or parasitological findings but multiple health impairments. The discoloration correlated significantly with the detection of immunosuppressive turkey hemorrhagic enteritis virus at the early stage and macro- and histological joint/bone lesions at the late fattening stage, indicating the presence of two different predisposing pathogeneses. Flocks not being vaccinated against hemorrhagic enteritis but having a virus-positive sample showed the highest prevalence of green liver discoloration and developed worse in various parameters. In conclusion, an adequate vaccination schedule and the prevention of field infections may lead to a decreased risk of performance reduction and improved animal health.

Is modified Carnoy's solution as effective as Carnoy's solution in terms of amount of bone necrosis and depth of penetration?

Carnoy's solution, a chemical cauterisation agent, has been indicated as one of the adjuvant treatment modalities for odontogenic keratocyst. In 2000, after the ban of chloroform many surgeons adopted the use of Modified Carnoy's solution. The purpose of this study is to compare the depth of penetration and amount of bone necrosis of Carnoy's versus Modified Carnoy's solution on the mandible of Wistar rats at different time intervals. Twenty-six male Wistar rats of six to eight weeks old, weighing approximately 150-200 grams, were allocated for this study. The predictor variables were type of solution and application time. The outcome variable was depth of penetration and amount of bone necrosis. Carnoy's solution was applied on the defect on the right side of the mandible and Modified Carnoy's solution on the left side for five minutes on eight rats, eight minutes on eight rats, and 10 minutes on eight rats. All specimens were subjected to histomorphometric analysis done using Mia image AR software. Univariate ANOVA test, and paired sample t test was done to compare the results. The depth of penetration for Carnoy's solution was more than Modified Carnoy's solution in the three different exposure times. Statistically significant results were observed at five minutes and eight minutes. The amount of bone necrosis was more in Modified Carnoy's solution. The results were not statistically significant at the three different exposure times. To conclude, when one wants to use Modified Carnoy's solution, the minimum exposure time should be 10 minutes to achieve similar results as those of Carnoy's solution.

Arsenic Trioxide-Induced Mandibular Osteomyelitis Associated with Mycotic Infestation: A Case Report.

Arsenic trioxide used in endodontic treatments has been shown to cause severe damages to surrounding bone and periodontal tissues. This report describes a case of alveolar osteomyelitis triggered by arsenic trioxide pulp devitalization and associated with mycotic infestation. Following clinical and radiological examinations, the concerned tooth was extracted, bone sequestrum was removed and granulation tissue was debrided. Histopathological biopsy examination, stained with hematoxylin/eosin, Grocott's silver methenamine and periodic acid-Schiff, confirmed the diagnosis of chemical osteomyelitis associated with fungal infestation. Six months postoperatively, normal bone healing was observed.

Outcome of Open Surgery in Disease Progression of Post-COVID Rhinomaxillary Mucormycosis Treated by Functional Endoscopic Sinus Surgery and Proposed Evaluation Scale for Maxillary Sinus Disease and Osteomyelitis.

Introduction: Rhinomaxillary Mucormycosis (RMM) is a condition peculiarly seen as post-COVID-19 opportunistic infections with Maxillary Sinus Disease and Osteomyelitis (MSDO). The open method of debridement and closed method are two types of surgical modalities available. There is no scoring method for this infection in maxilla. This paper aims to study the clinical and CT-based outcome of open versus closed surgery of MSDO in post-COVID-19 RMM and propose a new scoring method to evaluate the disease severity, progression as well as recovery. Material and Methods: Symptomatic cases of RMM (n = 17) with a history of closed surgical treatment were enrolled for this prospective clinical study. These cases were then treated by medicinal and open surgical method. The clinical and CT scan outcomes were compared by proposed new scoring method.The CT-based score for Maxillary Sinus Disease (MSD) and Maxillary Osteomyelitis (MO) from pre-FESS (CT1), Post-FESS (Preoperative, CT2), and Post-operative (CT3) were compared for both right and left sides. One-way ANOVA test and post HOC tests were used for statistical evaluation. Conclusion: The open method of maxillary sinus surgery has given significant improvement in the treatment of RMM already treated by a closed endoscopic approach. Supplementary Information: The online version contains supplementary material available at 10.1007/s12663-022-01803-5.