Effect of Three Different Injection Sites on the Success of Anterior Middle Superior Alveolar Nerve Block with 3% Mepivacaine: A Randomized Controlled Trial.

AIM: Anterior middle superior alveolar (AMSA) nerve block injection targets the anterior superior alveolar nerve and the middle superior alveolar nerve branches of the infraorbital nerve through nutrient canals. Therefore, the central incisor to the second premolar teeth of one quadrant can be anesthetized. The aim of the present study was to evaluate the efficacy of AMSA nerve block injection with 3% mepivacaine solution at three different injection sites. MATERIALS AND METHODS: In a double-blind crossover study, 47 volunteers participated and three AMSA nerve block injections of 3% mepivacaine solution without epinephrine were administered at the anterior, posterior, and the most common injection sites with a 1-week interval between injections. Anesthesia of the central incisor to the second premolar of the injected side was evaluated by using an electric pulp tester. The success of the injection was considered as lack of response to two consecutive 80 readings. The generalized estimating equation analytic tests were administered (α = 0.05). RESULTS: The success rate of the AMSA nerve block injection ranged from 27.5-47.5% for the most common injection site and 22.5-42.5% for both the anterior and posterior injection sites. CONCLUSION: Changing the injection site did not result in statistically significant improvements (p > 0.05). CLINICAL SIGNIFICANCE: Changing the injection site anteropos-teriorly did not influence the success rate of the AMSA nerve block injection.

General anesthesia in orthognathic surgeries: does it affect horizontal jaw relations?

PURPOSE: The aim of this study was to evaluate the influence of general anesthesia on centric jaw relation (CR) records of orthognathic surgical patients in different postural positions. MATERIALS AND METHODS: Fifty patients undergoing orthognathic surgery at Taleghani Hospital (Tehran, Iran) in 2008 were prospectively studied. CR records were obtained in conscious patients in 2 different positions (upright and supine) 1 day before surgery and in the supine position under general anesthesia. The impressions were made and the corresponding casts were mounted on a semiadjustable articulator. Differences were measured to the nearest 0.10 mm using a caliper. Paired t test and a general linear regression model were used for statistical analysis. RESULTS: Fifty patients (27 women and 23 men; mean age, 22.5 ± 3.5 yr) were enrolled. Angle Class I (group I), Class II (group II), and Class III (group III) malocclusions were detected in 16% (n = 8), 54% (n = 27), and 30% (n = 15) of patients, respectively. Although mean changes were smaller than 2 mm, statistically significant differences were found by paired t test in all Angle classification groups. No significant differences were found between the supine and conscious and the supine and unconscious patient positions in groups I and III (P > .05). However, in group II, this difference was statistically significant (P = .001). Regarding the impact of anesthesia on CR records of patients with different Angle classes, this study showed a significant effect, particularly in group II. Assessment of the outcome of interest (difference between the supine and conscious and the upright and conscious positions) versus position after adjustment for Angle class using a general linear regression model showed that the difference was significant only for Angle class (ß = +0.29; t = 3.05; P = .003). CONCLUSION: General anesthesia may not adversely affect the mandibular condylar position in orthognathic patients in a supine position compared with a supine and conscious position. However, among all study groups, group II showed more significant changes in CR records under general anesthesia. Oral and maxillofacial surgeons should be well aware of such changes in these particular positions and avoid possible mismanagement and potential complications.

Complication following reconstruction of orbital floor with temporalis-coronoid flap after subtotal maxillectomy.

A 33-year-old lady was referred to the Department of Oral and Maxillofacial Surgery of Taleghani hospital in 2008. She complained of firm swelling on the left side of her face with toothache, lacrimation, and nasal stiffness. There was a large mass in the left maxillary sinus with extension to the orbital floor, nasal bone, ethmoid sinus, and infratemporal fossa. The incisional biopsy revealed a neurofibroma of the maxilla. She underwent hemimaxillectomy and simultaneous reconstruction with temporalis-coronoid flap for orbital floor reconstruction. After 2 months' follow-up with no complication, she complained of left globe upward movement during gum chewing. The orbital and visual examinations were otherwise normal. This unusual complication has continued for 4 years with no resolution, although the patient does not worry about it any more.

Exfoliation and simultaneous formation of condylar process following chronic osteomyelitis of the mandible.

A 26-year-old physically challenged man with a history of 7 months' infection and pus discharge was referred to the oral and maxillofacial department. He had undergone right mandibular teeth extraction 1 year ago, which was followed by pus discharge from an extraoral submandibular fistula after 2 months. Again, incision and drainage and wide-spectrum antibiotic were prescribed, which subsided the symptoms for a short period but did not cure the condition. So, sequestrectomy, complete debridements, and antibiotic therapy were planned for him. In the operating room, it was revealed that the sequestrum was the condylar process, and in follow-up cone-beam computed tomography scan, the condyle was being regenerated simultaneously. One-year follow-up showed successful treatment of the condition.

Histologic evaluation of inferior alveolar lymphatics: an anatomic study.

The purpose of this study was to investigate the presence of a lymphatic system within the inferior alveolar canal, using specific immunohistochemical staining. Lymphatic capillaries are characterized by a thin wall with an irregular profile. They are superficial to organs and collect the lymph. Currently, the lymphatic system of the mandible and the floor of the mouth are attributed to the periosteum. The inferior alveolar canal within the mandible houses the inferior alveolar nerve, artery, and vein. Owing to the surgical vulnerability of the canal, several recent studies have focused on defining the exact contents and arrangements within the canal as well as precise measurements of the diameter of its components. No study has been performed on the existence of a lymphatic system within the inferior alveolar canal, the presence of which has significant importance for surgical management of malignant lesions. Presence of lymph channels would make the inferior alveolar nerve a potential route for spreading malignant cells. In this study, podoplanin-positive thin-walled vessels, considered to be lymphatic vessels, were traced within the inferior alveolar canal.

Use of amnion as a graft material in vestibuloplasty: a preliminary report.

OBJECTIVE: The aim of this study was to evaluate the clinical use of amnion as a biodegradable graft material for vestibuloplasty. STUDY DESIGN: Seven subjects who had been referred for preprosthetic surgery underwent mandibular vestibuloplasty using Clark's technique and amnion as graft material. Fresh amniotic membrane was placed in the area and an acrylic splint was used with soft liner and 0.4-mm wires to cover the surgical site. The area was reexamined after 1 week, 2 weeks, 4 weeks, 3 months, and 6 months. RESULTS: A white necrotic soft tissue layer could be seen with underlying hyperemic tissue and an average reduction of 1 to 3 mm in the depth of the labial vestibule after a week. By the end of the second week, the necrotic layer had disappeared, leaving slightly hyperemic mucosal tissue under. By the third week, the graft area could be noticed but the amnion had completely degenerated and disappeared. After 4 weeks, the subjects could be referred for their prosthodontic treatment. The reduction in the depth of the buccal vestibule ranged from 17% to 40% after 6 months' follow-up. CONCLUSION: Amnion might be used as a potential graft material for vestibuloplasty.

Nucleolar organizer regions in selected odontogenic lesions.

OBJECTIVE: The present study aimed to assess the usefulness of argyrophilic nucleolar organizer regions (AgNORs) as quantitative criteria in the diagnosis of odontogenic cysts and tumors. STUDY DESIGN: This descriptive cross-sectional study was done on archival paraffin blocks (n = 37), consisting of 10 conventional ameloblastomas, 7 cases of unicystic ameloblastoma, 10 odontogenic keratocysts, and 10 dentigerous cysts, all accessioned between 1994 and 2000. RESULTS: The findings showed a significant statistical difference among the 4 lesions (P <.001). Conventional and unicystic ameloblastomas had a significantly higher (P <.05) number of AgNORs than odontogenic keratocysts and dentigerous cysts. No significant differences were observed within each group of tumors or cysts. The number of AgNORs was also significantly higher (P <.005) in the nuclei of basal layer cells of the epithelial lining of keratocysts than in the nuclei of parabasal layer cells. AgNORs in conventional and unicystic ameloblastomas were smaller but more broadly distributed, which may indicate higher proliferative activity. CONCLUSION: AgNORs can be useful in the histopathologic differentiation of ameloblastomas from odontogenic cysts.