Topographic Features of the Right Mandibular Canal in Human Bone Atrophy Caused by Tooth Loss

Abstract

The aim is to determine the peculiarities of the topography of the right channel of the lower jaw in the bone atrophy, due to the terminal dentition defect. Objective. In general, for this research the method of "clinical sampling" involved sixty-eight computer-tomographic scans of the human mandible, which provide the best opportunities for diagnosis and carry proper information content for the task of this work, divided into four age groups, namely: the first group – up to 45 years old, the second group – 46-60 years old, the third group – 61-75 years old and the monitoring group – 25-75 years old, persons with natural dentition. Materials and methods. A set of research materials was conducted after paraclinical examination of digital records of 243 computed tomography cone-digital scans, which were taken by the Vatech PaX-I 3D Green extra-oral radiography system with a scan size range of 16 x 9 cm, which minimize the possibility of artifacts caused by patient movement, a focal spot of 0.5 mm (EC60336) on a 14-bit greyscale with a size of 0.2/0.3 voxels and due to the short scanning time, high-quality images were obtained. Results. Absolute values of the location of the mandibular canal of the patient of the first study group (control) with a natural dentition (48 years) in the projection: 1) 4.6 teeth in relation to: the upper edge of the alveolar part of the lower jaw (UE) is – 13.1 mm; the edge of the base of the lower jaw (EB) – 7.3 mm; the buccal surface of the body (BS) – 6.4 mm; the lingual surface of the mandibular body (LS) is – 1.6 mm; 2) 4.7 teeth in relation to: UE – 10 mm, EB – 5.0 mm, BS – 4.2 mm, LS – 1.4 mm. In the second study group, a 35-year-old patient with a terminal dentition defect, the topography of the right mandibular canal is characterized by morphometric values in the projection of the missing: 1) 4.6 tooth in relation to: UE – 13.1 mm EB – 5.4 mm, BS – 3.3 mm, LS – 1.6 mm; 2) 4.7 tooth in relation to: UE – 11.8 mm, EB – 6.8 mm, BS – 3.3 mm, LS – 1.9 mm. A 52-year-old patient of the third study group with a terminal dentition defect, the topography of the right mandibular canal is characterized by morphometric values in the projection of the missing: 1) 4.6 tooth in relation to: UE – 13.9 mm, EB – 7.4 mm, BS – 3.9 mm, LS – 5.7 mm, 2) 4.7 tooth in relation to: UE – 11.7 mm, EB – 7.6 mm, BS – 5.2 mm, LS – 4.6 mm. Topographic differences in the right mandibular canal are represented by a 64-year-old patient of the fourth study group with a terminal dentition defect, characterized by morphometric values in the projection of the missing: 1) 4.6 tooth in relation to: UE – 11.6 mm, EB – 5.7 mm, BS – 3.8 mm, LS – 4.9 mm; 2) 4.7 tooth (fig. 9) in relation to: UE – 10.0 mm, EB – 5.0 mm, BS – 4.2 mm, LS – 4.2 mm. Conclusion. The topography of the mandibular canal, and accordingly the laying of the neurovascular bundle in it, remain a guide when drawing up a treatment plan and for choosing rehabilitation procedures for patients with tooth loss, following existing and approved protocols. The analysis of the obtained absolute values does not reveal the corresponding patterns of topographic changes in the mandibular canal, depending on bone atrophy caused by the loss of the molars, in different age categories