Features of Dentin-Enamel junction in different types of teeth and designated age groups

Dentin-Enamel Junction is an anatomical interfacial region between the dentin and outer enamel coating in teeth. The uniqueness of this region is due to the incorporation of three morphologically different strong tissue of teeth. It has the utmost importance in clinical Dentistry as well as dental X-rays therefore needs to be cautiously addressed in routine dental practice. There are distinguished four types of connection within the cervical region of teeth: type 1 - cementum is partially covering enamel; Type 2 - Dentin-enamel is attached through endings "Margin-to-margin'' connection; Type 2 - cementum and enamel are not directly connected and there is denuded region up the teeth root. Type 4 -the enamel is covering the cementum; The main goal of our research was to study the different features of dentin-enamel Junction in various types of teeth and age groups. We studied 280 teeth which were assigned into four types of the group according to teeth types and three groups according to age: Group 1 - incisors (60 teeth); Group 2-canine (60 teeth); Group 3 - Premolars (80 teeth) in designated three age groups within the age intervals: 16-30 Y., 30-50Y and 50-70Y. 

According to the results of our research, in all types of teeth dominant type of dental-enamel Junction is type 3. The total percentage is 43.8%, and the frequency is increasing along with the rise in age and the maximum is reached in 50-70 year intervals respectively. This type of junction is also the most common in canines and has an equal frequency in molars and premolars. In all types of teeth the dental-enamel junction subtype is in distributed : Type 1 - 22,9%, Type 2 - 30%, Type 3 - 42,8%, Type 4 - 4,3%. besides that, type 1 junction in the 1 and 2 research group (molars and canine) has the same frequency in all designated age groups. Type 4 junction was not detected in any cases in the whole group neither in Group 2 nor in 50-70 years of intervals.