FEATURES OF COMPUTER SPATIAL VISUALIZATION AND HISTOTOPOGRAPHY OF ODONTOGENIC KERATOCYSTS OF THE JAWS WITH THEIR DIFFICULT DIAGNOSIS

This article is devoted to the establishment of radiological and histological features of odontogenic keratocysts under the conditions of an expansive lesion using computed tomography with contrast, panoramic radiography with subsequent biopsy of the neoplasm. These neoplasms are relatively common and account for 10–12% of all jaw cysts, usually occurring in the second and third decades of life. In the published materials, there are isolated data on histological studies on visualization of odontogenic keratocysts without signs of mineralization or calcification inside the lesion, which complicates differential diagnosis with other neoplasms of the jaw bone tissue. Most authors believe that this phenomenon is associated with a high concentration of viscous dense keratin protein in the lumen of the cyst. Мaterials and methods. Computer imaging was performed using the Morita R-100 cone-beam computed tomography software after contrast material injection. Scanning was performed with a step of 0.5 mm. To clarify the final clinical diagnosis, a biopsy was performed followed by a histological examination. The results. We established the following main radiological features of keratocyst: the shell of the neoplasm is often scalloped; there is an expansion of the neoplasm, especially in the direction of the lingual side, growth along the body of the mandibular bone; displacement of developing teeth; resorption of the roots of erupted teeth and extrusion of erupting teeth; on a panoramic X-ray, the neoplasm's lumen is transparent (45.7% of cases), and sometimes cloudy (54.3% of cases). According to contrast-enhanced CT, high attenuation in an expansive benign lesion of the lower jaw is suggestive of keratocyst. It was found that the high attenuation in this case is the result of a high concentration of protein in the dense keratin filling the lumen (82.5% of cases); may contain hemorrhage (10.2%) or calcification (7.3%), which was not detected during histological examination. Upon histological examination, all odontogenic keratocysts (OKC) are divided by us into parakeratotic and orthokeratotic subtypes, related to the characteristics of the mucous membrane and the type of keratin produced. Conclusions. We confirmed the opinion of many authors that compared to the parakeratotic subtype, the orthokeratotic subtype produces keratin more similar to the normal keratin produced by the skin.