Marsupialization before enucleation as a treatment strategy for a large calcifying odontogenic cyst: Case report.

INTRODUCTION: Odontogenic pathological lesions can generally be divided into cysts and tumors. Calcifying odontogenic cyst (COC) is a non-aggressive odontogenic cyst, however, in a few occasions, COC can show excessive growth and destruction. This study describes an uncommon aggressive presentation of a large COC and discusses the treatment strategies used to achieve a favorable result. PRESENTATION OF CASE: A 11-year-old child sought treatment for a painless growth on his mandible that caused facial asymmetry. On clinical and imaging examination, a large radiolucent lesion was observed in a panoramic x-ray involving the right side of the mandible. Radiopaque areas were observed within the lesion. Treatment comprised of an initial marsupialization followed by surgical removal of the lesion. Follow up extended for more than 10 years and no signs of recurrence were observed. DISCUSSION: Initial marsupialization was successfully employed in order to decrease the lesion, inducing bone formation, and reducing the risk of mandibular fracture and inferior alveolar nerve damage. Four months after marsupialization, the lesion substantially reduced its volume and enucleation with peripheral ostectomy was carried out. This approach allowed a safer surgical removal of the lesion and achieve an excellent result. CONCLUSION: Although some authors consider marsupialization as an unnecessary step that delays final treatment, when well indicated, it facilitates surgical treatment, promotes and preserves normal tissues, reduces the necessity of surgical reconstruction and costs, yet showing excellent results.

HIF-1α is Overexpressed in Odontogenic Keratocyst Suggesting Activation of HIF-1α and NOTCH1 Signaling Pathways.

Background: The odontogenic keratocyst (OKC) is an odontogenic cyst that shows aggressive and intriguing biological behavior. It is suggested that a hypoxic environment occurs in OKC, which led us to investigate the immunoexpression and location of hypoxia-inducible factor 1-alpha (HIF-1α) and other hypoxia-related proteins. Methods: Twenty cases of OKC were evaluated for the expression of Notch homolog 1 (NOTCH1), HIF-1α, disintegrin and metalloproteinase domain-containing protein 12 (ADAM-12), and heparin-binding epidermal growth factor-like growth factor (HBEGF) by immunohistochemistry and compared to eight control cases of calcifying odontogenic cystic (COC), orthokeratinized odontogenic cyst (OOC), and normal oral mucosa (OM) in basal and parabasal layers. Results: In OKC, all the proteins tested were expressed significantly higher in both basal (except for NOTCH1 and HBEGF in OOC) and suprabasal epithelial layers compared to controls. Looking at the epithelial layers within OKC, we observed an increased NOTCH1 and HIF-1α expression in parabasal layers. Conclusions: These results suggest that hypoxia occurs more intensively in OKC compared to COC, OM, and OOC. Hypoxia appeared to be stronger in parabasal layers as observed by higher HIF-1α expression in upper cells. Overexpression of NOTCH1, ADAM-12, and HBEGF in OKC was observed, which suggests that microenvironmental hypoxia could potentially regulate the expression of hypoxia-related proteins, and consequently, its clinical and biological behavior.

An Alternative Approach for Treating Severe Injured Temporomandibular Joints by Gunshot Wounds.

Temporomandibular joint (TMJ) reconstruction is a challenging clinical problem that has been revolutionized due to the development of total alloplastic TMJ replacement (TMJ-TJR); however, the costs are still very high. We used an alternative approach to treat comminuted mandibular condyle fracture with an unviable condyle head caused by gunshot wounds. Our surgical technique consisted of an extended preauricular incision; removal of the fractured condyle, bone fragments, and foreign bodies; reshape/flattening of the fracture edge; fixation of the articular disc (if viable); lining of the TMJ with temporalis muscle/fascia; application of Erich arch bars; and early elastic therapy. We successfully used this approach in five sequential cases that resulted in a good mouth opening (>35 mm) and satisfactory occlusion with teeth in maximum intercuspation. We believe that this technique is an excellent option for treating severe injured TMJs in places where TMJ-TJR is not available.

Proteasomal degradation of NOD2 by NLRP12 in monocytes promotes bacterial tolerance and colonization by enteropathogens.

Mutations in the nucleotide-binding oligomerization domain protein 12 (NLRP12) cause recurrent episodes of serosal inflammation. Here we show that NLRP12 efficiently sequesters HSP90 and promotes K48-linked ubiquitination and degradation of NOD2 in response to bacterial muramyl dipeptide (MDP). This interaction is mediated by the linker-region proximal to the nucleotide-binding domain of NLRP12. Consequently, the disease-causing NLRP12 R284X mutation fails to repress MDP-induced NF-κB and subsequent activity of the JAK/STAT signaling pathway. While NLRP12 deficiency renders septic mice highly susceptible towards MDP, a sustained sensing of MDP through NOD2 is observed among monocytes lacking NLRP12. This loss of tolerance in monocytes results in greater colonization resistance towards Citrobacter rodentium. Our data show that this is a consequence of NOD2-dependent accumulation of inflammatory mononuclear cells that correlates with induction of interferon-stimulated genes. Our study unveils a relevant process of tolerance towards the gut microbiota that is exploited by an attaching/effacing enteric pathogen.

Facial Fractures: Large Epidemiologic Survey in Northern Brazil Reveals Some Unique Characteristics.

PURPOSE: Facial fractures are an important health problem worldwide that can cause temporary or permanent disability and an economic burden. Identifying the risk factors associated with facial fractures is a valuable tool to create preventive public health strategies. This study evaluated the epidemiologic profile of facial fractures in northern Brazil. PATIENTS AND METHODS: Medical records of 1,969 patients who sustained facial fractures were analyzed for characteristics of the population, types of facial fractures, and treatment performed. RESULTS: The zygomatic complex was the most prevalent fracture site (28.8%). Road traffic accident (RTA) was the most common etiology (52%), followed by interpersonal violence (IPV; 34%). Among IPV cases, gunshot wounds were responsible for 14% of cases and 3% resulted from stab wounds. The third decade of life was the most prevalent age group, with a remarkable change in prevalence and etiology pattern at 15 years of age. Open reduction and internal fixation was the most used treatment, especially when the mandible was involved and at least 2 facial bones were fractured. There were 37 deaths (1.9%), with a higher risk observed for stab wounds (3.1-fold higher) and when at least 3 bones were fractured (4.1-fold higher). CONCLUSIONS: This epidemiologic survey identified RTA and IPV as important risk factors for facial fractures and a high prevalence of fractures caused by gunshot wounds. A unique preponderance of facial fractures caused by stab wounds was found, which was responsible for the highest risk of mortality.

Keratocystic odontogenic tumor overexpresses invadopodia-related proteins, suggesting invadopodia formation.

OBJECTIVE: Keratocystic odontogenic tumor (KOT) is an odontogenic neoplasm that shows aggressive clinical behavior and local invasiveness. Invadopodia are actin-rich cellular protrusions exhibiting proteolytic pericellular activity, thereby inducing focal invasion in neoplastic cells and increasing neoplasms aggressiveness. Thus, this study aimed to evaluate immunoexpression of invadopodia-related proteins, cortactin, MT1-MMP, Tks4, and Tks5, in KOT. STUDY DESIGN: Immunohistochemistry of 16 cases of KOT, eight cases of calcifying cystic odontogenic tumor (CCOT), and eight samples of the oral mucosa (OM) was carried out to assess the expression of the above described invadopodia-related proteins in the basal and suprabasal layer. RESULTS: KOT samples showed higher and significant immunoexpression of cortactin, MT1-MMP, TKs4, and TKs5 compared with the CCOT and OM samples. Significant expression of all these proteins was observed in the basal layer compared with the suprabasal layer in KOT. CONCLUSIONS: Overexpression of cortactin, MT1-MMP, TKs4, and TKs5 was observed in KOT compared with samples of CCOT and OM. These proteins were also overexpressed in the basal over the suprabasal layer of KOT samples. Taken together, these results suggest the participation of invadopodia-related proteins on the pathogenesis of this lesion.

Oral carriage of Candida species in HIV-infected patients during highly active antiretroviral therapy (HAART) in Belém, Brazil.

OBJECTIVE: To identify the oral carriage of Candida spp in patients infected by human immunodeficiency virus (HIV) and the possible correlation with clinical characteristics. STUDY DESIGN: Mucosal swab samples collected from 246 patients who were infected by HIV, did not have oral candidiasis, and were being treated with highly active antiretroviral therapy were analyzed. Yeast colonies that developed were identified by using the VITEK 2 automated system. RESULTS: Candida yeasts were present in 41.87% of the samples, and Candida albicans was the most prevalent (32.52%). Other identified Candida species were C tropicalis (4.88%), C parapsilosis (2.85%), C dubliniensis (0.81%), and C famata (0.81%). CONCLUSIONS: There was low rate of oral Candida carriage in patients infected by HIV who were on highly active antiretroviral therapy. A greater prevalence of C albicans than non-albicans Candida species was found at the species level. Prior candidiasis predicted the oral carriage of C albicans; however, it did not influence the carriage of non-albicans species. This is the first report of oral carriage of C famata in patients with HIV infection.

Giant life-threatening external carotid artery pseudoaneurysm caused by a mandibular condylar fracture.

OBJECTIVE: Vascular lesions are rare complications associated to mandibular condylar fractures. This paper aims to describe a case of a giant pseudoaneurysm involving the external carotid artery (ECA) caused by a condylar fracture. CASE REPORT: A 33-year-old man was the victim of traffic accident and presented with a panfacial fracture, including a bilateral condylar fracture. The condylar fracture was treated by closed reduction, and 4 weeks after treatment, the patient developed facial edema, which suggested postoperative infection. An attempt at draining it resulted in intensive bleeding. A computed tomographic angiography showed a huge pseudoaneurysm originating from the ECA. The patient was treated with surgery with ligation of the ECA and drainage of the pseudoaneurysm. CONCLUSION: Vascular complications associated with condylar fractures are rare, but surgeons should be aware of this type of complication, especially because of the high risk of serious damage, including death. The use of computed tomographic angiography is very helpful in the diagnosis of vascular lesions and also guides treatment.

Interfragmentary screw fixation of the zygomatic arch in complex midface and zygomaticomaxillary fractures.

Zygomatic arch reduction and fixation is a key point in the treatment of complex midface and zygomaticomaxillary fractures. High-impact frontal trauma can cause posterior displacement of zygomatic bone, with a sagittal fracture of the root of the zygomatic arch extending posteriorly to the glenoid fossa. Miniplate and screw fixation of this fracture requires a large detachment of soft tissue, thus being technically more difficult for proper fixation and increasing the risk of soft tissue damage. This report describes an operative approach for fixation of this type of fracture using an adaptation of the lag screw technique. After the initial reduction of zygomatic bone, the proximal segment of the zygomatic arch containing the sagittal fracture is anatomically reduced and a 2.0-mm titanium screw is placed with an inferior inclination of 10° to 15° into the mastoid cells of the temporal bone, thus avoiding intracranial screw placement. This technique showed excellent results in reduction and long-term stability. It facilitates the surgical procedure, decreases the risk of soft tissue damage, and can lower costs compared with conventional miniplate and screw fixation.

Traumatic pseudoaneurysm of the facial artery: late complication and effects on local blood flow.

OBJECTIVE: Pseudoaneurysms are vascular injuries resulting from a rupture of the vessel walls with blood extravasation into perivascular tissues. Proper treatment is required to prevent rupture and intense bleeding. This article reports a case of pseudoaneurysm of the facial artery that evolved to a late complication, presenting dehiscence of suture and exposure of the wound and bleeding after the initial injury and also discusses the effects of vascular response from the involved vessels by comparing them against the contralateral side. CASE REPORT: A healthy 17-year-old male was admitted with an injury of approximately 35 mm in length in the right cheek with an exposed clot inside the injury and local bleeding after a stabbing 11 days before. CT angiography showed rupture of the facial artery and formation of a pseudoaneurysm with an organized clot. The patient was treated by means of surgery under local anesthesia and intravenous sedation. The facial artery was located and attached by suture. The wound was explored and clots were removed. The patient was discharged on the first postoperative day and he had an excellent scarring standard with no unfavorable event. CONCLUSIONS: The authors conclude that this surgical technique is an effective method for treating such injuries, as it is easily performed and can be conducted by the oral and maxillofacial surgeon assistant.