Morphometric Assessment of Alveolar Antral Artery Using Medical Computed Tomography.

This study aimed to investigate the prevalence, diameter, and position of the alveolar antral artery (AAA) in paranasal sinus computed tomography (CT) images and to correlate the location of the AAA with tooth position, the presence of teeth, and residual alveolar bone height (ABH). A retrospective study was conducted at the Department of Oral and Maxillofacial Surgery, Seoul National University Dental Hospital, from November 2016 to October 2021. CT images of 100 maxillary sinuses from 50 patients managed for modified endoscopic sinus surgery and sinus lifting by a single surgeon were selected and obtained from the Infinitt picture archiving and communication system radiology system (Infinitt Healthcare Co., Seoul, Korea). The location of the AAA in the lateral wall of the maxillary sinus was evaluated in correlation with the area of the first and second molars (M1 and M2), the presence of teeth, and the residual ABH. In this study, we found that the intraosseous type is the most common type of AAA. Furthermore, the location and distance of the AAA are significantly affected by tooth position, an edentulous state in the case of the first molar, and residual ABH. Pre-evaluation of the diameter, position, and distance to the AAA using CT images is essential to help prevent hemorrhage. The existence and wide range of the AAA distances based on the tooth position, edentulous state, and residual ABH should be considered even if CT imaging cannot locate the AAA.

Appropriate Implant Rehabilitation in Patients With Iatrogenic Oroantral Fistula and Odontogenic Maxillary Sinusitis.

Oroantral fistula (OAF) is the most common etiology for odontogenic maxillary sinusitis that can be caused by tooth extractions, failed maxillary sinus lifts, bone grafts, and poor positioning of dental implant fixtures. A 52-year-old man presented with an OAF and maxillary sinusitis after implant placement and bone grafting. The authors treated the patient with modified endoscopic sinus surgery to obtain OAF closure and provided dental implant placement procedures afterward. The authors also treated 8 other similar cases with favorable outcomes. In this study, the authors report the know-how of implant placement procedures in patients with OAF and maxillary sinusitis.

Anterior Dental Implant in Grafted Cleft Alveolus: A Clinical Comparison Between Intramembranous and Endochondral Bone Graft.

BACKGROUND: Alveolar bone graft is usually performed during the early mixed dentition phase, at the chronological age of 6 to 8 years old, to reconstruct the cleft alveolus. As the appropriate time for implant placement is after completion of full growth, it can result in a likelihood of resorption. The aim of this study is to compare the clinical outcomes of anterior dental implants with delayed bone grafting using iliac crest (endochondral) and mandibular ramus or symphysis (intramembranous) bone in adolescents to adulthood patients with cleft alveolus. MATERIALS AND METHODS: This study included 10 patients with cleft alveolus who underwent delayed bone grafting with autogenous block bone and particulate cancellous bone and marrow (PCBM) from the mandibular ramus and symphysis with dental implant placement, and iliac crest. The success of the treatment was evaluated through clinical and radiographic examination including marginal bone loss measurement of the implants. RESULTS: All patients underwent delayed bone grafting between the ages of 11 and 21.1 years (mean age: 15.1±4.3 y). The implant diameters ranged from 3.8 to 4.5 mm and the lengths ranged from 8.0 to 11.5 mm. All of the implants were integrated successfully and survived during the 3-year follow-up period. CONCLUSIONS: Delayed bone grafting followed by implant placement showed long-term stability with satisfactory esthetic and functional rehabilitation. One of the main advantages of delayed bone grafting is to achieve adequate bone support for future dental implant placements with less bone resorption compared with those of primary, early secondary, and secondary bone grafting.

Legal Liability of a Dentist: Inferior Alveolar Nerve Damage After Calcium Hydroxide Extrusion.

ABSTRACT: During root canal treatments, calcium hydroxide can extrude through the apex causing chemical, mechanical, and/or thermal injuries to the inferior alveolar nerve, which can lead to neurological disorders. unfortunately, dental practitioner negligence can produce this potentially life-changing injury that can compromise the patient's life. The aim of this study is present a case of dental negligence by calcium hydroxide extrusion causing inferior alveolar nerve damage, discuss the methods of prevention, and characterize the medico-legal aspects of complication.

A Life-Saving Early Diagnosis of Burkitt Lymphoma: The Role of a Dentist.

ABSTRACT: Burkitt lymphoma (BL) is a subtype of Non-Hodgkin lymphoma, considered one of the fastest growing human tumors. Due to the highly aggressive nature of BL, a prompt diagnosis and aggressive chemotherapeutic treatment are essential. However, the clinical features of BL often can mimic periodontal disease or dentoalveolar abscess. The aim of this study is to present a case of a 31-year-old male patient who was referred to the department of oral and maxillofacial surgery for severe neurosensory disturbance and pain in the lower jaw. He was misdiagnosed with periodontitis and dental abscess at the local clinic. Based on radiographic findings, he was suspected of hematopoietic malignancy. He was referred to the department of hemato-oncology and diagnosed with BL. This case highlights the essential life-saving role of a maxillofacial surgeon in the early diagnosis of a rare malignancy.

Decompressive effects of draining tube on suppurative and sclerosing osteomyelitis in the jaw.

BACKGROUND: Osteomyelitis (OM) in the jaw is an inflammatory disease of osseous tissue that begins in the medullary space and progressively expands to the cortical portion of the bone, the Haversian system, the periosteum and the overlying soft tissue. Despite advances in dental and medical care, OM persists and is of important concern in modern medicine. Active negative pressure is known to prevent post-operative hematoma; decrease the number of bacterial pathogens, accumulation of toxins, and necrotic tissue; and promote osteogenesis and angiogenesis with the use of a draining tube such as the Jackson-Pratt (JP) or Hemovac. The purpose of this study was to assess the effectiveness of decompression for the treatment of OM in the jaw. METHODS: This retrospective study included a total of 130 patients, 55 patients with sclerosing OM and 75 patients with suppurative OM were included. The radiographic bone densities expressed as a grayscale values (GSVs), were measured using an easy digitalized panoramic analysis (EDPA) method, processed on the conditional inference tree, generated by the R program® 3.2.3 with a probability of 96.8%. Rectangle annotation analysis of INFINITT PACS® (INFINITT Healthcare, Seoul, Korea) of 50 mm2 was determined as the region of interest (ROI). Student's t-test and ANOVA were used to determine significance (p < 0.05). RESULTS: Significant changes was observed between radiographic bone density in the sclerosing type with drain and without drain at the six-month and one-year follow-up (p < 0.05). Significant difference was demonstrated between the suppurative OM with drain and without drain groups at the one-year follow-up (p < 0.05). CONCLUSION: The OM groups with drain exhibited more enhanced bone density compared to the groups without drain at the six-month and one-year follow-ups. The drain insertion for decompression is effective for the management of sclerosing and suppurative OM. It is recommended to implement it for the management of OM.

Effects of pentoxifylline and tocopherol on a rat-irradiated jaw model using micro-CT cortical bone analysis.

PURPOSE: A combination of pentoxifylline (PTX) and tocopherol (TP) is believed to reduce chronic fibrosis and induce bone healing in osteoradionecrosis (ORN) of the mandible, but evidence of its therapeutic effectiveness for cortical bone is lacking. This study was designed to determine the effect of combined PTX and TP (PTX + TP) on mandibular cortical bone remodeling in a rat model of ORN, using micro-CT and histological analysis. METHODS: Forty-eight 8-week-old male Sprague-Dawley rats were randomly divided into irradiated (n = 40) and non-irradiated (n = 8) groups. Animals in the irradiated group were divided into four sub-groups, including PTX, TP, PTX + TP, and normal saline. Three weeks after irradiation, mandibular posterior tooth extraction was performed, and animals were sacrificed 7 weeks after irradiation. The mandibles were analyzed using micro-CT and histological evaluation. RESULTS: The alveolar bone height, cortical bone thickness, cortical bone volume, and total cortical bone surface of the PTX + TP group were significantly greater than those of other irradiated groups (p < 0.05). In 3D reconstructed images, the residual volumes of cortical and cancellous bone were inadequate in the irradiated groups. CONCLUSION: We found that a combination of PTX and TP improved quality and quantity of cortical bone in irradiated rat mandibles, thus providing supporting evidence of its utility as a treatment and prophylactic agent in ORN. We observed inadequate volumes of cortical and cancellous bone in ORN mandibles, suggesting that cortical bone could play an important role in further ORN studies.

Autogenous Partial Bone Chip Grafting on the Exposed Inferior Alveolar Nerve After Cystic Enucleation.

This prospective study evaluated the clinical effectiveness of the new approach of partial autogenous bone chip grafts for the treatment of mandibular cystic lesions related to the inferior alveolar nerve (IAN). A total of 38 patients treated for mandibular cysts or benign tumors were included in this prospective study and subsequently divided into 3 groups depending on the bone grafting method used: cystic enucleation without a bone graft (group 1), partial bone chip graft covering the exposed IAN (group 2), and autogenous bone graft covering the entire defect (group 3). We evaluated the symptoms, clinical signs, and radiographic changes using dental panorama preoperatively, immediate postoperatively, and at 1, 3, 6, and 12 months postoperatively. Radiographic densities were compared using Adobe Photoshop CS5 (Adobe Systems Inc., San Jose, CA). Repeated measures analysis of variance was used for statistical evaluation with SPSS 22.0 (SPSS Inc, Chicago, IL), and P < 0.05 was considered statistically significant.Radiopacities were the most increased at 1 year postoperative in group 3; groups 2 and 3 did not show statistically significant differences, whereas groups 1 and 3 were statistically significant. In terms of radiographic bone healing with clinical regeneration of the exposed IAN, healing occurred in all patients, although the best healing was achieved in group 2.This autogenous partial bone chip grafting procedure to cover the exposed IAN is suggested as a new surgical protocol for the treatment of cystic lesions associated with the IAN.

Analysis of Microvascular Free Flap Failure Focusing on the Microscopic Findings of the Anastomosed Vessels.

Microvascular flap reconstruction is known as successful technique, although vascular thrombosis can cause free flap failure. To analyze the histologic characteristics and causes of free flap failure, this clinical study examined failed free flaps, including the microanastomosed sites. This study included a total of 5 failed flaps, including 3 radial forearm free flaps, 1 latissimus dorsi free flap, and 1 fibular free flap, all performed with microvascular reconstruction surgery from 2009 to 2011 at Seoul National University Dental Hospital. At the resection surgeries of the failed nonviable flaps, histologic specimens including the microanastomosed vessels were acquired. For light microscope observation, the slides were stained with hematoxylin and eosin (HE), and also with Masson trichrome. Selected portions of graft tissue were also observed under transmission electron microscope (TEM). It was found that the cause of flap failure was the occlusion of vessels because of thrombi formation. During the microanastomosis, damage to the vessel endothelium occurred, followed by intimal hyperplasia and medial necrosis at the anastomosed site. In the TEM findings, some smooth muscle cells beneath endothelium were atrophied and degenerated. The formation of thrombi and the degeneration of the smooth muscle cells were coincident with vascular dysfunction of graft vessel. The damaged endothelium and the exposed connective tissue elements might initiate the extrinsic pathway of thrombosis at the microanastomotic site. Therefore, it is suggested that accurate surgical planning, adequate postoperative monitoring, and skillful technique for minimizing vascular injury are required for successful microvascular transfer.

Clinical retrospective analysis of peri-implant oral malignancies.

PURPOSE: Complications of implant prostheses have direct correlation with the increased use of implants for dental rehabilitation. In this study, we present cases of peri-implant oral malignancies (PIOM) around dental implants and a retrospective analysis of patients treated for PIOM. METHODS: The retrospective analysis was performed with patients treated for PIOM at the Department of Oral and Maxillofacial Surgery of the Seoul National University Dental Hospital between 2006 and 2014. The patient records were thoroughly screened for previous medical issues, human papilloma virus infections, and other clinical data with a focus on relevant information such as localization, time from implant insertion to the development of the carcinoma, implant type and prosthetic rehabilitation. RESULTS: Twenty-one patients were diagnosed with PIOM. The male-to-female ratio was 1.625. The mean age of the patients was 60.42 ± 9.35 years old. Three patients reported ongoing alcohol/tobacco consumption. Five patients had a history of previous oral cancer surgery or exhibited mucosal lesions. The time from implant placement until carcinoma diagnosis was 49.13 ± 33.63 months on average. Most PIOM patients (95.2%) were diagnosed with SCC. All patients had previously been treated for peri-implantitis. In 85.7% of the patients, prostheses were observed on the opposing teeth where PIOM occurred. CONCLUSION: Based on the review of these cases, it can be deduced that there is a possibility that implant treatment and galvanic currents between prosthesis may constitute an irritant and/or inflammatory cofactor which contributes to the formation and/or development of malignant tumors. Patients at potential risk may benefit from individualized recall intervals and careful evaluations.

Ultrastructural and immunohistochemical evaluation of hyperplastic soft tissues surrounding dental implants in fibular jaws.

In reconstructive surgery, complications post-fibula free flap (FFF) reconstruction, notably peri-implant hyperplasia, are significant yet understudied. This study analyzed peri-implant hyperplastic tissue surrounding FFF, alongside peri-implantitis and foreign body granulation (FBG) tissues from patients treated at the Department of Oral and Maxillofacial Surgery, Seoul National University Dental Hospital. Using light microscopy, pseudoepitheliomatous hyperplasia, anucleate and pyknotic prickle cells, and excessive collagen deposition were observed in FFF hyperplastic tissue. Ultrastructural analyses revealed abnormal structures, including hemidesmosome dilation, bacterial invasion, and endoplasmic reticulum (ER) swelling. In immunohistochemical analysis, unfolded protein-response markers ATF6, PERK, XBP1, inflammatory marker NFκB, necroptosis marker MLKL, apoptosis marker GADD153, autophagy marker LC3, epithelial-mesenchymal transition, and angiogenesis markers were expressed variably in hyperplastic tissue surrounding FFF implants, peri-implantitis, and FBG tissues. NFκB expression was higher in peri-implantitis and FBG tissues compared to hyperplastic tissue surrounding FFF implants. PERK expression exceeded XBP1 significantly in FFF hyperplastic tissue, while expression levels of PERK, XBP1, and ATF6 were not significantly different in peri-implantitis and FBG tissues. These findings provide valuable insights into the interconnected roles of ER stress, necroptosis, apoptosis, and angiogenesis in the pathogenesis of oral pathologies, offering a foundation for innovative strategies in dental implant rehabilitation management and prevention.

Functional rehabilitation of the maxillary sinus after modified endoscopic sinus surgery for displaced dental implants.

PURPOSE: Dental implants may become displaced into the maxillary sinus due to insufficient primary stability, changes in nasal air pressure, or surrounding bone resorption and should be removed as soon as possible. The aim of this study was to evaluate the efficacy of the modified endoscopic sinus surgery (MESS) approach for removal of displaced dental implants. METHODS: From September 2010 to November 2021, we studied 15 cases with displaced implants in the maxillary sinus. The patient characteristics, medical history, clinical and imaging results, and post-removal outcomes were retrospectively assessed. RESULTS: The symptoms included sinusitis (100%), pain (26.6%), postnasal drip (6.6%), nasal obstruction (26.6%), and oroantral communication (26.6%). Two cases were managed through the crestal approach (13.3%), while two cases were treated with the Caldwell-Luc procedure (13.3%). One case was addressed using functional endoscopic sinus surgery (6.7%), while 10 cases were managed with the MESS approach (66.7%). MESS allows functional rehabilitation of mucociliary clearance by the cilia in the sinus membrane. Implant displacement into the maxillary sinus can be classified as early, late, or delayed displacement. CONCLUSIONS: MESS is a reliable treatment option that can identify migrated dental implants in any part of the sinus with endoscopic assistance for functional rehabilitation of the maxillary sinus without postoperative sequelae.

Radiographic evaluation before surgical extraction of impacted third molar to reduce the maxillary sinus related complication.

Objectives: Surgical extraction of maxillary third molars is routine in departments devoted to oral and maxillofacial surgery. Because maxillary third molars are anatomically adjacent to the maxillary sinus, complications such as oroantral fistula and maxillary sinusitis can occur. Here we explore the factors that can cause radiographic postoperative swelling of the maxillary sinus mucosa after surgical extraction. Materials and Methods: This retrospective study reviewed the clinical records and radiographs of patients who underwent maxillary third-molar extraction. Preoperative panoramas, Waters views, and cone-beam computed tomography were performed for all patients. The patients were divided into two groups; those with and those without swelling of the sinus mucosa swelling or air-fluid level in a postoperative Waters view. We analyzed the age and sex of patients, vertical position, angulation, number of roots, and relation to the maxillary sinus between groups. Statistical analysis used logistic regression and P<0.05 was considered statistically significant. Results: A total of 91 patients with 153 maxillary third molars were enrolled in the study. Variables significantly related to swelling of the maxillary sinus mucosa after surgical extraction were the age and the distance between the palatal cementoenamel junction (CEJ) and the maxillary sinus floor (P<0.05). Results of the analysis show that the relationship between the CEJ and sinus floor was likely to affect postoperative swelling of the maxillary sinus mucosa. Conclusion: Maxillary third molars are anatomically adjacent to the maxillary sinus and require careful handling when the maxillary sinus is pneumatized to the CEJ of teeth.

Clinical significance of drug cessation on medication-related osteonecrosis of the jaw in patients with osteoporosis.

Objectives: Suspending bisphosphonates (BPs) to reduce the risk and severity of medication-related osteonecrosis of the jaw (MRONJ) remains controversial. In this study, we quantitatively evaluated the clinical significance of BP suspension before surgery in osteoporosis patients with MRONJ. Materials and Methods: We analyzed 24 osteoporosis patients with MRONJ who were treated from 2012 to 2020 at Seoul National University Dental Hospital and compared the treatment outcomes of those who suspended BPs with those who did not. The number of surgical interventions, follow-up panoramic radiographs for relative bone density measurement, and laboratory blood tests including white blood cells, erythrocyte sedimentation rate, absolute neutrophil count, hemoglobin, hematocrit, and alkaline phosphatase were analyzed. ANOVA, Student's t -test, and Mann-Whitney U tests were used to compare results. Fisher's exact test was used to discover the association between treatment outcome and BP suspension, and Pearson's correlation test was used to measure the statistical relationship between the changes in serum inflammatory markers. Results: The number of interventions was significantly higher in the non-drug suspension group due to recurrence (p<0.05). The relative bone density in patients who suspended BPs was significantly different over time (p<0.05), with the highest density at one-year follow-up. Fisher's exact test shows an association between successful treatment outcomes and BP suspension. The alkaline phosphatase and erythrocyte sedimentation rate levels decreased significantly in the BP-suspended group, and a positive correlation was found between these elevated markers. Conclusion: A significant increase in bone density throughout follow-up and a lower number of interventions were found in the BP suspension group compared to the non-drug suspension group. Also, BP suspension decreased inflammatory markers in the serum after surgery, resulting in good treatment outcomes. BP suspension is a prognostic factor for MRONJ and should be implemented before surgery.

Energy-dispersive X-ray spectroscopic investigation of a fractured non-submerged dental implant associated with abutment fracture.

The biocompatibility and durability of implant fixtures are major concerns for dentists and patients. Mechanical complications of the implant include abutment screw loosening, screw fracture, loss of implant prostheses, and implant fracture. This case report aims to describe management of a case of fixture damage that occurred after screw fracture in a tissue level, internal connection implant and microscopic evaluation of the fractured fixture. A trephine bur was used to remove the fixture, and the socket was grafted using allogeneic bone material. The failed implant was examined by scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS), which revealed a fractured fixture with both normal and irregular bone patterns. The SEM and EDS results give an enlightenment of the failed fixture surface micromorphology with microfracture and contaminated chemical compositions. Noticeably, the significantly high level of gold (Au) on the implant surface and the trace amounts of Au and titanium (Ti) in the bone tissue were recorded, which might have resulted from instability and micro-movement of the implant-abutment connection over an extended period of time. Further study with larger number of patient and different types of implants is needed for further conclusion.

Guidance and rationale for the immediate implant placement in the maxillary molar.

Objectives: While the reliability of immediate implant placement in the maxillary molar has been discussed, its significance is questionable. There have been no guidelines for case selection and surgical technique for successful treatment outcomes of immediate maxillary molar implants. Therefore, in this study, we classified alveolar bone height and socket morphology of the maxillary molar to establish guidelines for immediate implant placement. Materials and Methods: From 2011 to 2019, we retrospectively analyzed 106 patients with 148 immediate implants at the Department of Oral and Maxillofacial Surgery, Seoul National University Dental Hospital. Inclusion and exclusion criteria were applied, and patient characteristics and treatment results were evaluated clinically and radiologically. Results: A total of 29 tapered, sand-blasted, large-grit, and acid-etched (SLA) surfaces of implants were placed in 26 patients. The mean patient age was 64.88 years. Two implants failed and were reinstalled, resulting in a 93.10% survival rate. Fluctuating marginal bone level changes indicating bone regeneration and bone loss were observed in the first year following installation and remained stable after one year of prosthesis loading, with an average bone loss of 0.01±0.01 mm on the distal side and 0.03±0.03 mm on the mesial side. Conclusion: This clinical study demonstrated the significance of immediate implant placement in maxillary molars as a reliable treatment with a high survival rate using tapered SLA implants. With an accurate approach to immediate implantation, surgical intervention and treatment time can be reduced, resulting in patient satisfaction and comfort.

Reasonable necessity of preoperative laboratory tests in office-based oral and maxillofacial surgery.

Objectives: As medical history before surgery is often based on patient reporting, there is the possibility that patients intentionally hide underlying diseases or that dentists cannot recognize abnormal health states. Therefore, more professional and reliable treatment processes are needed under the Korean dental specialist system. The purpose of this study was to elucidate the necessity of a preoperative blood testing routine prior to office-based surgery under local anesthesia. Patients and. Methods: Preoperative blood lab data for 5,022 patients from January 2018 to December 2019 were assembled. Study participants were those who underwent extraction or implant surgery under local anesthesia at Seoul National University Dental Hospital. Preoperative blood tests included complete blood count (CBC), blood chemistry, serum electrolyte, serology, and blood coagulation data. Values outside of the normal range were considered an "abnormality," and the percentage of abnormalities among the total number of patients was calculated. Patients were divided into two groups based on the presence of underlying disease. The rates of abnormalities in the blood tests were compared between groups. Chi-square tests were performed to compare data from the two groups, and P<0.05 was considered statistically significant. Results: The percentages of males and females in the study were 48.0% and 52.0%, respectively. Of all patients, 17.0% (Group B) reported known systemic disease, while 83.0% (Group A) reported no specific medical history. There were significant differences between Groups A and B in CBC, coagulation panel, electrolytes, and chemistry panel (P<0.05). In Group A, the results of blood tests that required a change in procedure were identified even though the proportion was very small. Conclusion: Preoperative blood tests for office-based surgery can detect underlying medical conditions that are difficult to identify from patient history alone and can prevent unexpected sequelae. In addition, such tests can result in a more professional treatment process and build patient confidence in the dentist.

Analysis of acute sinusitis-related early failed implant surface: a combined histological, electron microscopy, and X-ray spectroscopy approach.

BACKGROUND: Even though dental implants are a reliable choice for dental rehabilitation, implant failures due to various etiologies have been reported. Early implant failures account for 2 to 6% of installed implants and are reported to have a higher rate than late failures, regardless of loading time. We herein report three cases of acute sinusitis and early implant failure with implants that failed within 1 month after installation. The aim of this study was to evaluate the surface properties of early failed implants and peri-implant tissue to determine the early osseointegration pattern in acute sinusitis-related failed implants as well as the possible role of surface contamination in the failure of osseointegration. RESULTS: A combined histological, electron microscopy, and X-ray spectroscopy approach was used to characterize the surface of non-osseointegrated titanium implants and the surrounding biological tissues. Morphologic scanning electron microscopy revealed a heterogeneous surface and irregular osseointegration. The implant surface was covered mostly by carbon- and oxygen-rich organic matter. Energy-dispersive X-ray spectroscopy surface analysis of three implants showed the incorporation of some contaminants in both the upper and apical regions. Carbon, nitrogen, sodium, silicon, chlorine, sulfur, gold, and zirconium were detected on the surface of one or more failed implants. Fibrosis, lymphocytic, and macrophage infiltrates and a high activation of osteoclasts surrounding the bone graft particles were detected in the surrounding tissues. CONCLUSIONS: The etiology and mechanism of early implant failure, especially in sinus-related cases, as well as the proper management interventions to minimize the rate of early implant failures, are of great concern. No matter how confident and accurate the surgeon's operation, there may be unknown errors in the whole procedure that no one knows about. Rather than errors related to the implant surface, it is expected that there were invisible problems during the evaluation of the patient's own unique sinus mucosal inflammation or the operator's own procedure. Furthermore, well-designed researches are necessary to reveal the effect of material-related factors on acute sinus complication and early implant failure.

Decompression effects on bone healing in rat mandible osteomyelitis.

Osteomyelitis (OM) of the jaw is usually caused by a chronic odontogenic infection. Decompression is the release the intraluminal pressure in the cystic cavity allowing gradual bone growth from the periphery. The aim of this study was to analyze the effectiveness of decompression in an OM jaw model. A 4-mm-diameter defect was made on mandibles of fourteen Sprague-Dawley rats and inoculated with S. aureus (20 µl of 1 × 107 CFU/ml) injection. Two weeks later, four groups were made as non-treatment (C1), only curettage (C2), curettage and decompression (E1), and curettage and decompression with normal saline irrigation (E2). After four weeks, each group was analyzed. Most micro-CT parameters, including bone mineral density [0.87 (± 0.08) g/cm3] with bone volume [0.73 (± 0.08) mm3] was higher in E2 group than that of C1 group (p = 0.04, p = 0.05, respectively). E2 group in histology showed the highest number of osteocytes than those of control groups, 91.00 (± 9.90) (p = 0.002). OPN were expressed strongly in the E1 ("5": 76-100%) that those of other groups. Decompression drains induced advanced bone healing compared to that of curettage alone. Therefore, it could be recommended to use decompressive drain for enhancing the jaw OM management.

The effects of pentoxifylline and tocopherol in jaw osteomyelitis.

OBJECTIVES: Pentoxifylline (PTX) is a methylxanthine derivative that has been implicated in the pathogenesis of peripheral vessel disease and intermittent lameness. The purpose of this study was to investigate the effect of PTX and tocopherol in patients diagnosed with osteoradionecrosis (ORN), bisphosphonate-related osteonecrosis of the jaw (BRONJ), and chronic osteomyelitis using digital panoramic radiographs. MATERIALS AND METHODS: This study was performed in 25 patients who were prescribed PTX and tocopherol for treatment of ORN, BRONJ, and chronic osteomyelitis between January 2014 and May 2018 in Seoul National University Dental Hospital. Radiographic densities of the dental panorama were compared prior to starting PTX and tocopherol, at 3 months, and at 6 months after prescription. Radiographic densities were measured using Adobe Photoshop CS6 (Adobe System Inc., USA). Blood sample tests showing the degree of inflammation at the initial visit were considered the baseline and compared with results after 3 to 6 months. Statistical analysis was performed using the Mann-Whitney test and repeated measurement ANOVA using IBM SPSS 23.0 (IBM Corp., USA). RESULTS: Eight patients were diagnosed with ORN, nine patients with BRONJ, and the other 8 patients with chronic osteomyelitis. Ten of the 25 patients were men, average age was 66.32±14.39 years, and average duration of medication was 151.8±80.65 days (range, 56-315 days). Statistically significant increases were observed in the changes between 3 and 6 months after prescription (P<0.05). There was no significant difference between ORN, BRONJ, and chronic osteomyelitis. Only erythrocyte sedimentation rate (ESR) was statistically significantly lower than before treatment (P<0.05) among the white blood cell (WBC), ESR, and absolute neutrophil count (ANC). CONCLUSION: Long-term use of PTX and tocopherol can be an auxiliary method in the treatment of ORN, BRONJ, or chronic osteomyelitis in jaw.