Radiological examination of the relationship between the pterygomaxillary junction and fracture pattern.

BACKGROUND: Le Fort 1 (LF1) osteotomies are widely used to correct midface deformities. To move the maxilla freely, the ptery-gomaxillary junction (PMJ) must be separated. When performing this osteotomy, the pterygoid plate must remain intact. The objective of this study was to evaluate relationship between the anatomical features of the PMJ and fracture patterns in LF1 osteotomy. METHODS: Pre-operative and post-operative cone-beam computed tomography images of 41 patients (82 samples) who have undergone LF1 osteotomy surgery were radiologically evaluated. Morphologic measurements of the pterygomaxillary fissure area and pterygoid plate were carried out. Moreover, pterygomaxillary separation was divided into the clean-cut, maxillary sinus, and pterygoid plate fracture types. RESULTS: Statistically significant difference was observed between clean-type fracture and pterygoid plate fracture groups' thickness of the pterygoid process and thickness of the pterygomaxillary region. CONCLUSION: Anatomical variations make it difficult to separate the PMJ properly. Low thickness of PMJ increases the risk of unwanted fractures; however, according to our experience, the use of an osteotome with an incorrect angle, excessive force, and inexperienced surgeons can also cause undesirable pterygoid plate fractures.

Inferior alveolar nerve injury due to the extrusion of calcium hydroxide during endodontic treatment: A case report.

Although many materials are used for root canal fillings in endodontic treatment, calcium hydroxide has been preferred for many years due to its bactericidal effect and biocompatibility. Calcium hydroxide can be applied in more than one form. In this case study, calcium hydroxide in viscous form, applied into the root canal during endodontic treatment, overflowed from the apical part of the tooth to the inferior alveolar nerve canal. Postoperative paraesthesia was observed in the patient. Dental volumetric tomography was performed to study the extent of sealer in the inferior alveolar nerve canal. Considering the short resorption time of the calcium hydroxide paste, no surgical intervention was performed on the patient. After 6 months, the root canal material was completely resorbed, and paraesthesia decreased. At the 3-year follow-up, the patient's paraesthesia had completely disappeared.