Proper Management of Amalgam Powder Embedded in the Alveolus.

The presence of foreign bodies in the mandible is not listed as a risk factor or absolute contraindication for implant rehabilitation. However, possible complications caused by foreign bodies, such as infection and cyst formation, could lead to implant failure. The authors report a case of dental implant placed 4 months after the surgical removal of embedded amalgam in the mandibular alveolus using a trephine bur and bone grafting with mineralized freeze-dried bone allograft. Clinical and radiographic evaluations were performed at each appointment to assess factors such as pain, implant mobility, probing depth, and marginal bone loss around the implant. Within 3 years of implant placement, there were no clinical signs and symptoms and no obvious radiographic marginal bone loss. Dental implant installation appears to be safe following the elimination of foreign materials, so long as anatomic and biological factors and appropriate implant choice, are taken into consideration.

Gingivo-Periosteal Expansion of Edentulous Jaw Crest with An Osmotic Self-Inflatable Expander: A Preclinical in Vivo Study.

This study examined the biocompatibility and expansion volume of tissue expanders utilizing rabbits and beagles as experimental models. The self-inflatable expander was provided using a Tissue balloon® (Neobiotech Co., Seoul, Korea). In 9 adult rabbits, a Tissue balloon® was placed under the lateral mandibular periosteum via an extraoral approach. After 2, 3, and 4 weeks (n=3), the expanders were removed, and soft tissue and bone samples were collected for analysis. Histomorphometric analysis and measurements of expander characteristics were performed. In 5 Beagles, all premolars were extracted. Three months after extraction, tissue expanders were placed in the maxilla and mandible, adjacent to dental extraction sites, and removed after 3 weeks. Gingival parameters were measured before and after expansion. Blood perfusion in the oral mucosa was assessed using a laser Doppler flowmeter at different time points. After three weeks, dogs were euthanized, and tissue samples were collected for histologic analysis, focusing on inflammatory response, bone formation, and gingival thickness changes. In the rabbit study, measurements of size, weight, and volume showed significant increases over 4 weeks. Swelling peaked at 2 weeks postimplantation and then gradually stabilized. Histologic examination revealed no signs of inflammation, and expanders were covered by collagen-rich capsules. Some bone resorption was noted due to pressure from the expanders, but the resorption was not significant. In the beagle study, twenty tissue expanders were implanted; 1 expander was lost, and 9 wounds dehisced during soft tissue healing. However, no signs of infection were noted. Histologic evaluation showed bone atrophy, attributed to swelling pressure, at the recipient site. Gingival thickness was not decreased. Perfusion measurements indicated that expansion did not affect microvascular circulation adversely. Overall, both studies suggest that tissue expanders demonstrate biocompatibility and successful expansion volume in vivo, with minimal adverse effects on surrounding tissues and microvascular circulation.

Long-term Follow-up of Implant Installation Following Multiple Distraction Osteogenesis in Maxillofacial Gunshot Wounds.

Distraction osteogenesis (DO) is a reconstruction technique developed in the fields of oral and maxillofacial surgery and plastic surgery, addressing both vertical and horizontal bone deficiencies and enhancing soft tissue volume to facilitate subsequent dental implant placement. In this treatment method, devices are placed to stretch the bone gradually to stimulate the formation of new bone, effectively filling the existing defect to treat maxillofacial deformities or repair posttraumatic injuries. This case report presents an almost 20-year long-term follow-up of jaw defect reconstruction resulting from a gunshot injury, using DO with multiple distractors. Details on the frequency, period of DO, and subsequent implant installation in the distracted anterior jaw area are outlined. This case exhibits DO treatments that reconstructed effectively severe bone defects in the jaws. The quality of bone generated during the DO process was both functionally and esthetically satisfactory for subsequent implant rehabilitation.

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.

Surgical management and final outcomes of chondrosarcoma of the temporomandibular joint: case series and comprehensive literature review.

BACKGROUND: Surgical management for chondrosarcoma of the temporomandibular joint (TMJ) is challenging due to the anatomical location involving the facial nerve and the functional joint. The purpose of this case series was to analyze the largest number of TMJ chondrosarcoma cases reported from a single institution and to review the literature about chondrosarcoma involving the TMJ. METHODS: Ten TMJ chondrosarcoma patients at Seoul National University Dental Hospital were included in this study. Radiographic features, surgical approaches, histopathologic subtypes, and treatment modalities were evaluated. All case reports of TMJ chondrosarcoma published in English from 1954 to 2021 were collected under PRISMA guidelines and comprehensively reviewed. RESULTS: The lesions were surgically resected in all 10 patients with efforts to preserve facial nerve function. Wide excision including margins of normal tissue was performed to ensure adequate resection margins. All TMJs were reconstructed with a metal condyle except one, which was reconstructed with vascularized costal bone. At last follow-up, all patients were still alive, and there had been no recurrence. Among 47 cases (patients from the literature and our cases), recurrence was specified in 43 and occurred in four (9.5%). CONCLUSIONS: For surgical management of TMJ chondrosarcoma, wide excision must consider preservation of the facial nerve. Reconstruction using a metal condyle prosthesis and a vascularized free flap is reliable. A more conservative surgical approach correlates with a favorable prognosis for facial nerve recovery. Nevertheless, wide excision is imperative to prevent tumor recurrence. In cases in which the glenoid fossa is unaffected by the tumor, it is deemed unnecessary to reconstruct the glenoid fossa within an oncological setting.

Long-term Stability Over 2 Years After Isolated Maxillary Orthognathic Surgery Combined With Mandibular Autorotation in Risk Patients for Condylar Resorption.

OBJECTIVE: Counterclockwise rotation of mandible can cause condylar resorption and condylar displacement posteroinferiorly after maxillary orthognathic surgery with mandibular in patients with high-angle mandibular retrognathism. This study was aimed to evaluate long-term stability >2 years and postoperative changes of condylar displacement. MATERIALS AND METHODS: In 15 patients who underwent Le Fort I osteotomy with mandibular autorotation, postoperative stability was cephalometrically investigated until 2 years. Condylar changes were analyzed with transcranial temporomandibular joint projection. Correlation between condylar displacement and surgical movement was analyzed. RESULTS: Significant clockwise relapse of mandible ( P <0.01 for SNB reduction and backward movement of point B) was observed between 6 months and >2 years after surgery, even though the values were small (0.5±0.1 degrees and 1.14±0.13 mm, respectively). The condyle was displaced posteroinferiorly immediately after surgery; however, it achieved a stable position at postoperative 6 weeks. The amount of vertical condylar displacement was significantly correlated with surgical change in mandibular posterior border sagittal angle, palatal plane angle, facial height ratio, and point B in the horizontal dimension. Greater mandibular rotation prompted more vertical condylar displacement. CONCLUSIONS: Small mandibular relapse in long term should be considered after maxillary orthognathic surgery with mandibular autorotation, although it is regarded as a surgical maneuver to minimize mandibular instability in patients susceptible to postoperative condylar resorption.

Metastasis of Renal Cell Carcinoma to the Mandible.

Renal cell carcinoma (RCC) is the most common tumor of the kidney. Although RCC often metastasizes to other organs, metastasis to the head and neck region is rare, and metastasis to the mandible is very unusual. Given the fact that metastasis of primary neoplasms is not always predictable, it is essential to rule out metastatic carcinoma in jaw lesions. We herein report a rare presentation of metastasis of RCC to the mandible, in which the metastatic lesion in the oral cavity was found first, followed by the primary lesion, in a 22-year-old girl who suffered from pain in the left temporomandibular joint on mouth opening and hypoesthesia of the left chin, left lower lip, and left lower gum.

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.

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.

Craniofacial Epidermoid and Dermoid Cysts.

BACKGROUND: Epidermoid and dermoid cysts are benign developmental anomalies that can form anywhere in the body. Despite the rarity of incidence in the head and neck, they can arise at a variety of craniofacial locations. The purpose of this study was to analyze the clinical features of epidermoid and dermoid cysts arising in the craniofacial region with a literature review. METHODS: A retrospective study was designed, and clinical features and surgical considerations were investigated from a literature review. Cases of epidermoid cysts in the scalp, temporal area, glabellar area, mouth floor, and buccal mucosa were described. RESULTS: Dermoid cysts in more lateral regions of the scalp are rarely associated with intracranial extension. Because temporal dermoid cysts have a high rate of intracranial extension, radiological evaluation of the lesions in the temporal area is imperative. Epidermoid cysts in the glabellar area are usually superficial. Consideration of the surgical approach for an epidermoid cyst of the mouth floor is important. Because epidermoid cysts in the buccal mucosa are extremely rare, differential diagnosis was emphasized. Epidermoid cysts in the scalp, in the temporal intradiploic area, on the glabellar area in the periorbital region, in the mouth floor, and in the buccal mucosa were surgically excised considering the depth and location. Ten cases of epidermoid cysts in the buccal mucosa were retrieved from the literature review. CONCLUSIONS: Consideration of the anatomic locations of epidermoid and dermoid cysts in the craniofacial region might help facilitate accurate diagnosis and treatment.

Primary intraosseous carcinoma in the pediatric and adolescent mandible.

BACKGROUND: Primary intraosseous carcinoma (PIOC) is a rare malignant odontogenic tumor that predominantly occurs in males older than 50 years. PIOC can be misdiagnosed as odontogenic cyst because it occasionally shows a well-defined border on radiography. In this study, related literatures of pediatric and adolescent PIOC cases were analyzed under strict PRISMA guidelines along with an adolescent case who was provisionally misdiagnosed as an odontogenic cyst. METHODS: All case reports for PIOC published in English from 1966 to 2021 were collected. Cases under the age of 20 were classified as pediatric and adolescent populations in this study. A total of 12 pediatric and adolescent cases including 11 PIOCs from the literature and one new case of a 14-year-old female were analyzed. Clinical and radiographic features, diagnosis and treatment approaches, and prognosis were investigated. RESULTS: Ages ranged from 4 to 18 years. The female to male ratio was 1.4:1. Seven cases occurred in the mandible. Swelling was observed in 11 patients. The radiologic borders were well-defined in six cases and corticated in four cases. Tooth displacement and root resorption were observed in four and six cases, respectively. The provisional diagnosis for seven patients was odontogenic cyst and enucleation was performed in six cases including the new case. During the follow-up period, local recurrence occurred in three patients. The pediatric and adolescent PIOC cases with local recurrence showed poor prognosis. The locally recurred lesion in the new case did not decrease in size despite concurrent chemo-radiation therapy. CONCLUSIONS: Three-dimensional imaging modalities and incisional biopsy with multiple specimens are necessary to rule out PIOC in the lesions with atypical radiographic findings. PIOC should be diagnosed differentially from odontogenic cyst even in pediatric and adolescent populations to properly manage the disease with poor prognosis.

Tapered, Sand-Blasted, Large-Grit, and Acid-Etched Surfaced Internal Dental Implant in the Diverse Pathologic Jaw.

PURPOSE: The treatment of pathologic lesions in jaws either through conservative or radical approaches, frequently leads to a loss of teeth. As a result, patients will experience diminished masticatory and phonetic function as well as esthetic deficits. In this manuscript, we report multiple cases of successful implant rehabilitation after the conservative treatment of pathologic lesions in jaws utilizing allogeneic bone grafts and the installation of implant fixtures. MATERIALS AND METHODS: In this study, we examined 8 patients with 8 different kinds of pathologic lesions in their jaws, who were treated with a conservative approach and rehabilitated with bone grafts and implant installations using internal dental implant type with tapered, sand-blasted, large-grit, acid-etched surfaces. Marginal bone loss was analyzed through radiograms, and the implant survival rates and graft outcome evaluations were recorded. RESULTS: No significant difference was found in the mean marginal bone loss throughout the follow-up period. The survival rate of the implant and the success rate of graft were recorded as 100%. CONCLUSIONS: The results of this study suggest that conservative surgical management for pathologic lesions based on the understanding of the pathologies can be helpful for successful oral rehabilitation. In bone grafting, it is necessary to determine an appropriate timing and method considering the risk of recurrence and the vascularity of the recipient site. For subsequent implant placement, selecting an implant system suitable for the site of placement and placing it within 3 to 6 months after bone grafting can help the long-term maintenance of the grafted bone and dental implant.

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.

Odontogenic Keratocyst in the Masseter Muscle.

ABSTRACT: Odontogenic keratocyst (OKC) arising from purely soft tissue other than the mucosa covering the jawbone is rare. A 57- year-old Korean female patient presented with a lump on her right cheek, which had been suspected as a fibrotic mass on the buccinator muscle by the local clinic. Magnetic resonance imaging showed an ovoid mass in the buccal space just before the right ramus with an enhancing component in the marginal area, and the interior of the mass revealed a fluid signal. Histopathologically, the lesion showed the typical features of OKC and the cyst wall contained some daughter cysts and the minor salivary gland, muscle, and fat tissues. The authors report a very unique case of OKC arising in the masseter muscle.

Energy-Dispersive X-Ray Spectroscopic Analysis of an Extraorally Installed Implant in a Silicone Facial Prosthesis Patient.

ABSTRACT: Titanium implants are considered to be highly biocompatible relative to other metals, and the use of this metal is increasing more and more. However, studies on its possible toxic effects are rare. A patient who had a large midface defect was treated with an implant-supported magnet-retained silicone prosthesis; however, the extraoral implant failed. Scanning electron microscopy and energy dispersive X-ray spectroscopy was used to analyze the surface characteristics and the chemical compositions of the failed implant fixture and attached bone tissue. The contamination of the implant and bone tissue with aluminum (Al), iron (Fe), and mercury (Hg) potentially had an influence on the integration of bone tissue and the health of peri-implant tissue. The exposure of the facial prosthesis and its implant to the external environment may have caused the contamination. Careful clinical examination during the follow-up period and adequate hygiene is essential for the longterm success of implant-supported prostheses.

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.

Chronic Expanding Hematoma on Latissimus Dorsi Free Flap Donor Site Grown Over 17 Years.

ABSTRACT: The latissimus dorsi free flap (LDFF), that provides long vascular pedicle with rich vascularization and adequate bulk for maxillofacial defect coverage, is utilized in microvascular surgery for maxilla-mandibular reconstruction with high success rate, less morbidity, and ability to provide facial symmetry. In addition, it can reduce the risk of adjuvant therapies, such as radiotherapy. Seroma formation at the donor site following LDFF harvest has been reported as a common postoperative sequela. On the other hand, chronic expanding hematoma (CEH) in an LDFF donor site is a rare postoperative complication. in this case report, the authors describe a rare occurrence of a solidified CEH on an LDFF donor site in a male patient 17 years after mandible reconstruction surgery. For treatment, the patient underwent mass resection with drain placement and quilting suture, resulting in reduction of the hematoma and faster healing.

Accurate Mandible Reconstruction by Mixed Reality, 3D Printing, and Robotic-Assisted Navigation Integration.

ABSTRACT: Mandibular reconstruction is one of the most complex procedures concerning the patient's postoperative facial shape and occlusion condition. In this study, the authors integrated mixed reality, three-dimensional (3D) printing, and robotic-assisted navigation technology to complete the mandibular reconstruction in a novel and more accurate way. Mixed reality can visualize the significant anatomical structures of the operative area, but only be used in simulated operation by now. Three-dimensional printing surgical guide plate makes it easy to separate tissue, while imprecision often occurs due to the potential of displacement and deformation. In recent years, most robotic-assisted navigation surgery technology can only achieve precise position by 2D view on the screen but not realistic 3D navigation. in this study, the integrated 3 technologies were used in mandibular reconstruction. Preoperative imaging examination was performed, and the data were imported into the digital workstation before operation. First, the original data was edited and optimized to reconstruct the digital model and formulate the surgical plan. Then MR was used to output the visualized project and matched the 3D reconstruction model in reality. The 3D plate was printed for surgical guidance. Last, robotic-assisted navigation was used to guide and position the vascularized fibula autograft and the immediate dental implantation. In conclusion, the authors integrated the 3 technologies and constructed a new digital surgical procedure to improve surgical accuracy and simplify the procedure comparing with traditional surgery.

Factors Affecting Functional Sensory Recovery After Inferior Alveolar Nerve Repair Using the Nerve Sliding Technique.

PURPOSE: The nerve sliding technique (NST) was introduced for repairing inferior alveolar nerve (IAN) defect and overcoming the disadvantages of conventional surgical treatment methods such as nerve graft. This study was conducted to identify factors associated with functional sensory recovery (FSR) following inferior alveolar nerve repair using the NST. PATIENTS AND METHODS: This was a retrospective cohort study including all patients who underwent IAN repair using the NST at Seoul National University Dental Hospital, Department of Oral and Maxillofacial Surgery from February 2009 to March 2020. The damaged part of the IAN was excised, and the incisive branch was transected intentionally to perform direct anastomosis without tension. Cox proportional hazard analysis was utilized to determine the relationships between predictor variables (age, gender, chief complaints, preoperative sensory results, duration from injury to repair, length of nerve tissue resected during the procedure, and neuroma formation) and outcome variable (time to FSR). RESULTS: The sample was composed of 16 patients with a mean age of 56.1 ± 10.1 years, 25% were males and 75% were females. The mean nerve gap deficit was 7.69 mm (3-15 mm). Ten patients (62.5%) achieved FSR with a median time from operative treatment to FSR of 84.5 days. Dental implant placement was found as the main cause for IAN injury (93.8%) and 56.2% of patients complained of hypoesthesia and dysesthesia. Factors associated with time to FSR at 1 year were age, chief complaint, and early repair. Younger patients (P = .041) and patients without dysesthesia (P = .019) were more likely to achieve FSR. Higher proportion of early repair group achieved FSR, although not statistically significant (P = .068). CONCLUSIONS: The use of NST in repair of IAN defects up to 15 mm achieved 62.5% FSR. Younger age and absence of dysesthesia were associated with higher FSR.

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.