The principles and practice of dentistry : including anatomy, physiology, pathology, therapeutics, dental surgery and mechanism / by Chapin A. Harris.

  • Harris, Chapin A. (Chapin Aaron), 1806-1860.
Date:
1906
Catalogue details

Licence: Public Domain Mark

Credit: The principles and practice of dentistry : including anatomy, physiology, pathology, therapeutics, dental surgery and mechanism / by Chapin A. Harris. Source: Wellcome Collection.

    1162/1184 (page 1162)
    instrument is undoubtedly the best with which to acquire articulation, and were it not for the perishable nature of the material of which it is made, there is no case in which it should not be preferred. It imitates the form and action ,of the natural velum quite as well as artificial teeth imitate the shape of natural teeth and perform the function of mastication, and with it one can learn to articulate more readily than with an obturator. “ Obturators are simply plugs filling up to a greater or less extent the upper pharynx or the posterior nares. When properly adapted they are especially valuable to supplement the use of an artificial velum, and in many cases their use would be justified as a primary instrument. “ No rule can be given, or description made, which will indicate to the inexperienced which sort of apparatus is likely to confer the most help in any case. No study of a model of the parts involved will be of much advantage. It is only the experienced eye, watching the action of the muscular tissues in the remainder of the palate and of the superior pharynx, which will guide to a determination. “Nor is it at all possible, by observation of such action, to form any opinion of the effect upon the speech. That can be known only by hear¬ ing. With a personal expe¬ rience of more than thirty years, and an observation of more than a thousand cases, I have failed to discover all the causes which are in force in producing mal-articulation. It is easy to discern physical causes, but the esoteric physiological causes are so remote that to me they still continue to be a mystery. “I have seen horrible deformities in the absence of the velum, the hard palate, and all the anterior part of the alveolar arch, including also the upper lip, where the speech was absolutely unintelligible. Fig. 1245 represents the model of such a case. Here the inexperienced would readily find a cause for the mal-articulation. But I have seen very small clefts, fissures of the velum only, nasal passages normal, neither vomer, turbinated, nor palatal bones abnormal, and no hare¬ lip, where the speech was as defective as in the former case. Fig. 1246 represents one of the latter class. “I have also seen an extensive fissure, involving hard and soft palates, a portion of the alveolar process, and a harelip, where but that the lip directed attention to the possibility of a palatal cleft, such Fig. 1244.