Summary During inflammation, lymphangiogenesis takes place to enhance the transport of filtered fluid, proteins, and immune cells. Dental pulp tissue is frequently exposed to inflammatory insults, but the lymphatic system of the pulp and its responses to injury have not been investigated in detail using specific lymphatic markers. The aim of this study was to evaluate and to compare the lymphatic system in health dental pulp and pulp with inflammation, and to establish whether lymphangiogenesis takes place during dental pulp inflammation. Ten pulps with irreversibile pulpitis and eleven samples of healthy dental pulps were included in this study. All pulp samples were analyzed microscopically using the standard hematoxylin-eosin (HE) staining to detect the presence of inflammation. Immunohistochemical staining was performed using monoclonal anti-CD31 antibody (DAKO) at dilution 1:20. Microvessels identified by CD31, in which lumen the red blood cells were not detected, were considered as lymph vessels. Active areas of lymphangiogenesis (“hot spots”) were selected using low magnification. Images from five high power fields in the hot spot areas were recorded for each sample. Lymph vessels were counted using ImageJ program. The total number of lymph vessels so obtained was then divided by the number of the counted hot spots, and the result was used to denote the lymph vessel density. The mean number of lymphatic vessels, detected by CD31, in the group without inflammation was significantly lower than in the group with inflammation (3.75 versus 13.58, t=7.093, p<0.001). The present study established an increased number of lymphatic vessels in the inflamed human dental pulp suggesting that inflammation contributes to lymphangiogenesis.

ACTA FACULTATIS MEDICAE NAISSENSIS UDC: 616.314 SU M M A RYCemento-enamel junction (CEJ) is an important anatomical structure of the tooth, which is located in the cervical part of the tooth between the crown and root, or at the contact point between the enamel which overlaps the tooth crown and cementum overlapping the root dentin.There are four possible relationships between two tissues that make the CEJ such as: the cement overlaps the enamel; the enamel overlaps the cement; the enamel and cement abut each other with no overlap; the enamel and cement are not in contact. The aim of this study was to determine the relationship between the enamel and cement which make the CEJ in different types of permanent teeth.The material consisted of 30 permanent teeth with intact CEJ. Staining of CEJ was carried out using the methylene blue. After staining, the tooth was washed under the running water and drying at room temperature. Each tooth was longitudinally cut in the vestibular-oral direction. Observation of CEJ was done with Leica light microscope and images were obtained using a Nikon camera.The results indicated that the most common form of CEJ between the cement and enamel in the region of CEJ was that cement and enamel abutted without overlap (36.7%), followed by the cement overlapping the enamel (33.3%), and the cases when a gap between the cement and enamel (16.7%) was present, and when the enamel overlaped the cement (13.3%).Because of the morphological diversity of CEJ, careful performing of dental interventions in the region of tooth neck is necessary because they may change the morphology of this region, induce the pathological processes and hypersensitivity of teeth.