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68 After the deciduous teeth loosen, they are shed and are soon replaced by eruption of their permanent successors. Deciduous incisors and canines are replaced by permanent teeth of the same name. Deciduous molars, however, are replaced by premolars. Thus the permanent molars erupt without hav‑ ing any deciduous predecessors. Deciduous teeth become loose by resorp‑ tion of their roots which deprives them of their attachment to the jaws. The unerupted permanent successors lie adjacent to the absorbing deciduous roots and are thus able to erupt into their places when the deciduous teeth are fially shed. 25. Find English equivalents for these words and word combina- tions in the text: Известно как; прорезываются после рождения; индивидуальное различие; прорезывание начинается; завершается; вскоре заменяют‑ ся; того же названия; расшатываются из-за рассасывания их корней; непрорезавшиеся; способны прорезываться. Speaking 26. Read, translate and reproduce the dialogues. – 1 – Teacher: Can you tell me what you know about enamel? Student: Enamel is the outer covering of the crown. It is the hardest substance in the body. It is insensitive to pain. It consists of enamel prisms, cemented together by the interprismatic substance. Teacher: You are right. Your answer is good. The next question is: what do you know about cementum and dentine? Student: Cementum is the outer covering of the root and is similar in structure to bone. Dentine occupies the interior of the crown and root. It is very sensitive to pain. Teacher: Good. And what is pulp? Student: The pulp is purely soft tissue. It contains blood vessels and nerves. The pulp occupies the centre of the dentine. Vessels and nerves of the pulp enter the root apex through the apical foramen and pass up the root canal into the crown. The space occupied by the pulp here is called the pulp chamber.