Haj Yahya Bahaa, Bar-Hai Dror, Samehov David, Chaushu Gavriel, Hamzani Yafit
Oral and Maxillofacial Surgery Private Clinic, Herzliya 4672211, Israel.
Department of Oral and Maxillofacial Surgery, Beilinson Hospital, Rabin Medical Center, Petach Tikva 4941492, Israel.
J Clin Med. 2021 Sep 22;10(19):4293. doi: 10.3390/jcm10194293.
"Big-nose variant" is an anatomical phenomenon defined as the pneumatization of inferior third of the nasal cavity within the alveolar ridge while simultaneously displacing the maxillary sinus laterally. The purpose of the present study was to assess the prevalence of the big-nose variant phenomenon and suggest a morphology classification system. Diagnostic anatomical evaluation was performed in a tertiary medical center on 321 randomly selected maxillary cone beam computerized tomography scans of patients who presented at an oral and maxillofacial department. Two anatomical categories were defined for anatomical identification: classes for horizontal mesiodistal distribution, and divisions for vertical distribution. Class 2, defined as location of the nasal/sinus border between the distal edge of the canine up to the distal edge of second premolar, was found to be the most prevalent (64.6%). Class 3, defined as location of the nasal/sinus border distal to mesial edge of the first molar, was found in 17.9% of cases. Regarding the divisions category, in 96% and 58.2% of teeth examined, nasal cavity alone was found to be superior to the canine and first premolar, respectively, defined as Division A. In 46.9% and 85.6% of teeth examined, maxillary sinus alone was located above the second premolar and first molar, respectively, defined as Division C. Identifying Class 3 on the paraxial reconstruction is the first step in identifying big-nose variant, with further assurance gained from each determining division. The use of the classes and divisions may enable better maxillary treatment planning, alert surgeons for the unexpected, and avoid complications.
“大鼻变异”是一种解剖学现象，定义为牙槽嵴内鼻腔下三分之一的气化，同时上颌窦向外侧移位。本研究的目的是评估大鼻变异现象的发生率，并提出一种形态学分类系统。在一家三级医疗中心，对随机选取的321例在口腔颌面科就诊患者的上颌锥形束计算机断层扫描进行了诊断性解剖评估。为便于解剖识别定义了两个解剖类别：水平近远中分布类别和垂直分布分区。第2类定义为鼻/窦边界位于尖牙远中边缘至第二前磨牙远中边缘之间，是最常见的（64.6%）。第3类定义为鼻/窦边界位于第一磨牙近中边缘远端，在17.9%的病例中发现。关于分区类别，在检查的牙齿中，分别有96%和58.2%的牙齿发现鼻腔单独位于尖牙和第一前磨牙上方，定义为A区。在检查的牙齿中，分别有46.9%和85.6%的牙齿发现上颌窦单独位于第二前磨牙和第一磨牙上方，定义为C区。在轴位重建上识别第3类是识别大鼻变异的第一步，通过确定每个分区可进一步确认。使用这些类别和分区可以更好地进行上颌治疗计划，提醒外科医生注意意外情况，并避免并发症。
