Schoppe Christin, Hellige Maren, Rohn Karl, Ohnesorge Bernhard, Bienert-Zeit Astrid
Clinic for Horses, University of Veterinary Medicine Hannover, Foundation, Buenteweg 9, 30559, Hannover, Germany.
Institute for Veterinary Biometry and Epidemiology, University of Veterinary Medicine Hannover, Foundation, Buenteweg 2, 30559, Hannover, Germany.
BMC Vet Res. 2017 Sep 6;13(1):280. doi: 10.1186/s12917-017-1200-7.
Modern imaging techniques such as computed tomography (CT) and magnetic resonance imaging (MRI) have the advantage of producing images without superimposition. Whilst CT is a well-established technique for dental diagnostics, MRI examinations are rarely used for the evaluation of dental diseases in horses. Regarding equine endodontic therapies which are increasingly implemented, MRI could help to portray changes of the periodontal ligament and display gross pulpar anatomy. Knowledge of age-related changes is essential for diagnosis, as cheek teeth and surrounding structures alter with increasing age. The aim of the present study was to highlight the advantages of CT and MRI regarding age-related changes in selected equine cheek teeth and their adjacent structures.
The CT and MRI appearances of the maxillary 08 s and 09 s and adjacent structures were described by evaluation of post-mortem examinations of nine horses of different ages (Group A: <6 years, B: 6-15 years, C: ≥16 years). Most of the tissues selected were imaged accurately with MRI and CT. Magnetic resonance imaging gives an excellent depiction of soft endo- and periodontal units, and CT of hard dental and bony tissues. Negative correlation between dental age and pulpar sizes was found: 71.3% of the changes in pulp dimensions can be explained by teeth aging. Pulpar sizes ranged from 14.3 to 1.3 mm and were significantly smaller in older horses (p < 0.05). A common pulp chamber was present in 33% of the teeth with a mean dental age of 2.25 years. Ninety-four percent of the 08 and 09 alveoli of all groups were in direct contact with the maxillary sinus. An age-related regression was found (R = 0.88) for the distance between alveoli and the infraorbital canal.
The present study provides information about the dental and periodontal age-related morphology and its visibility using different imaging techniques. These results aid in evaluating diagnostic images and in deciding which is the superior imaging modality for clinical cases.
计算机断层扫描（CT）和磁共振成像（MRI）等现代成像技术具有生成无重叠图像的优势。虽然CT是牙科诊断的成熟技术，但MRI检查很少用于评估马的牙科疾病。对于越来越多地实施的马牙髓治疗，MRI有助于描绘牙周韧带的变化并显示大体牙髓解剖结构。了解与年龄相关的变化对于诊断至关重要，因为颊齿及其周围结构会随着年龄的增长而改变。本研究的目的是强调CT和MRI在所选马颊齿及其相邻结构与年龄相关变化方面的优势。
通过对9匹不同年龄马（A组：<6岁，B组：6 - 15岁，C组：≥16岁）的尸体解剖检查进行评估，描述了上颌第8和第9颊齿及其相邻结构的CT和MRI表现。大多数所选组织在MRI和CT上成像准确。磁共振成像能出色地描绘牙髓和牙周软组织单位，而CT能清晰显示牙齿硬组织和骨组织。发现牙齿年龄与牙髓大小呈负相关：牙髓尺寸变化的71.3%可由牙齿老化解释。牙髓大小范围为14.3至1.3毫米，老年马的牙髓明显更小（p < 0.05）。33%的牙齿存在共同髓腔，平均牙齿年龄为2.25岁。所有组中94%的第8和第9齿槽与上颌窦直接接触。发现齿槽与眶下管之间的距离存在与年龄相关的回归（R = 0.88）。
本研究提供了有关牙齿和牙周与年龄相关形态及其使用不同成像技术的可视性信息。这些结果有助于评估诊断图像并决定哪种成像方式在临床病例中更具优势。
