A system of dental surgery / by Sir John Tomes.

Date:
1887
Catalogue details

Licence: Public Domain Mark

Credit: A system of dental surgery / by Sir John Tomes. Source: Wellcome Collection.

Provider: This material has been provided by the Royal College of Physicians of Edinburgh. The original may be consulted at the Royal College of Physicians of Edinburgh.

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    Behind the alveoh for the first temporary molars we have a large open socket, which, in the upper maxilla, has but a very imperfect posterior wall. Projecting inwards from the free edge of the outer and inner alveolar walls, we may observe small spicula, the rudiments of septa which are destined to divide the cavity into two distinct sockets, and thus separate the pidps of the second temporary and first permanent molar teeth, both of which at present occupy one large alveolus. The division usually takes place a little earlier in the lower than the upper jaw. The groove which marks the passage of the nerve and artery in the floor of the socket of the first temporary molar, can be traced through the alveoli of the two posterior teeth, back to the inferior dental foramen, which is situated midway between the angle of the jaw and the edge of the inner wall of the alveolus of the first i^ermanent molar, a little below the floor of the posterior part of the last alveolus. At this period the articular process of the lower jaw is scarcely raised above the level of the alveolar edge, while the angle is projected downwards a little below the general level of the inferior margin of the jaw. The coronoid pro- cess rises at an angle of forty-five degrees from the alveolar edge, its ascent commencing at the anterior boundary of the socket of the first permanent molar. In the upper jaw the zygomatic process proceeds outwards from the anterior margin of the large open soclcet of the second temporary molar. It is necessary to notice, with some degree of [icciu-acy, the relative position of these points, as in tracing the growth of the jaws, changes occur which can be recognised only by a knowledge of the preceding conditions. The temporary teeth at nine months are partly formed. The central incisors are calcified through the greater length of the crown; but the lateral teeth are less advanced. The terminal points only of the canines are calcified^ while the masticating surfaces of the first temporary molars are com- pleted, excepting the enamel, which at this stage has not