FACE. 



219 



uiid the symphysis inclines from the shrunken 

 alveolar border downwards and forwards to the 

 base of the bone, and (fives to the chin the 

 projecting appearance which is so character- 

 istic of this period of life. 



Tlic artii-iilittiiiHs i>t' tin t'ncc comprise those 

 of the upper and that of the lower jaw. 



The articulations of the bones of the upper 

 jaw with each other and with those of the cra- 

 nium are all of the kind called suture, but they 

 present considerable variety in the extent, form, 

 and adaptation of their articular surfaces. 

 Those bones of the face which contribute to 

 form its columns of support, and to which this 

 part of the head owes its strength and resistance 

 to violence, have their articular surfaces for the 

 most part broad and rough, presenting emi- 

 nences and depressions which are adapted to 

 those of the contiguous bone; examples of this 

 firm articulation are seen, 1. at the anterior 

 part of the intermaxillary suture, where the two 

 palatine plates unite and form the horizontal 

 column or base of the upper jaw; 2. at the 

 IHIMI/ columns, where the nasal bones and the 

 nasal processes of the upper maxilla; unite with 

 the frontal ; 3. on the sides of the face, or 

 where the bones form their lateral or malar 

 columns, viz. at the jugo-maxillary and jugo- 

 frontal articulations. The spheno-jugal articu- 

 lation, seen within the orbit, and the zygomatic 

 or temporo-jugal, though formed by the union 

 of comparatively narrow surfaces or borders, 

 derive strength from their irregularity, and, in 

 the case of the zygomatic suture, from its in- 

 dented form, which maintains its security from 

 vertical blows, as the curved direction of the 

 zygoma protects it from lateral injury. 



Those sutures of the faco which are, strictly 

 speaking, harmonic, are such as are not exposed 

 to any considerable pressure ; they present, 

 nevertheless, some varieties in their mode of 

 juxta-position. In some the adaptation is 

 direct, as in the pterygo-palatine. In others 

 one border or surface is received by another 

 (sc/iiiulyletis), as in the articulations of the 

 vomer with the sphenoid above, and with the 

 groove in the palatine plates of the upper max- 

 illary and palate bone inferiorly. Sometimes 

 the surfaces are simply applied against each 

 other, as the nasal plate of the palate bone on 

 the nasal surface of the upper maxillary. 

 Lastly, the edges may alternately overlap each 

 other, as those of the nasal and upper maxillary 

 bones. 



In all the sutures of the face, whatever may 

 be the adaptation of the osseous surfaces, we 

 find interposed a thin layer of cartilage uniting 

 the contiguous surfaces of the bones. This is 

 easily shown in some of the sutures by mace- 

 ration, and only disappears in places as some 

 of the bones become united with advancing 

 age ; 



The great number of pieces of which the 

 upper jaw consists, and the varying form and 

 direction of the sutures, all contribute, with the 

 figure of the bones themselves, to give strength 

 to this part of the skull, and to break the force 

 of blows In diffusing them over a widely ex- 

 tended surface. 



The sutures of the face derive their names 

 from the bones which contribute to form them; 

 thus we have between the orbits the fronto- 

 nasal, fronto-maxillary, and fronto-lachrymal 

 sutures, all contributing to form part of the 

 transverse suture. (See CRANIUM.) Ix>wer 

 down we find the nasal, the naso-maxillary, 

 and the lachrymo-maxillary, which turns at 

 right angles backwards along the inner wall of 

 the orbit into the ethmoido-maxillary and pa- 

 lato-orbitar sutures. On the outer side of the 

 orbit may be observed the fronto-jugal and 

 spheno-jugal sutures ; on the zygomatic arch 

 the temporo-jugal suture ; and below the pro- 

 minence of the cheek, the jugo-maxillary 

 suture, which is seen both on the anterior and 

 posterior surface of the upper jaw. On the 

 roof of the mouth are seen the longitudinal and 

 the transverse palatine sutures, the former 

 formed by the intermaxillary in front, and by 

 the inter-palatine suture behind : the latter is 

 often termed the transverse or horizontal palato- 

 maxillary suture. There are some other sutures 

 within the nose which it is unnecessary to enu- 

 merate. 



The lower jaw articulates with the cranium 

 by diarthrosis: this important joint will be 

 particularly described in the article TEMPORO- 



MAMI.I.UIY ARTICULATION. 



The bones of the face are invested with 

 periosteum or a fibrous membrane, which is 

 variously modified and arranged in the orbits, 

 nose and mouth, &c. 



ABNORMAL CONDITIONS OF THE BONES OF 

 THE FACE. 



In the true acephalous ftetus the bones 

 of the face as well as those of the cranium 

 are of course wanting, but the former are 

 generally found in what are termed the false 

 Acephalia (see ABNORMAL CONDITIONS OF 

 THE CRANIUM) ; it sometimes happens, not- 

 withstanding, that the bones of the face are but 

 imperfectly developed, presenting a variety of 

 conformations which it is unnecessary to parti- 

 cularise. The bones of the face, in some cases 

 alone, and in others in conjunction with those 

 of the cranium, not unfrequently acquire a de- 

 gree of development quite disproportionate with 

 the rest of the skeleton. In Corvisart's Journal 

 de Mdecine the case of a Moor is cited, whose 

 head and face were so enormous that he could 

 not stir abroad without being followed by the 

 populace. It is related that the nose of this 

 man, who was half an idiot, was four inches 

 long, and his mouth so large that he would bite 

 a melon in the proportion that an ordinary per- 

 son would eat an apple. I have now before 

 me the skull of a native of Shields, who was 

 remarkable during life for the length of his 

 face ; the entire head is large, but the bones of 

 the face, and particularly the lower jaw, are 

 enormously long. The abnormal development 

 of the facial bones generally affects one jaw 

 only, and more frequently the lower, as in the 

 example just mentioned. Other cases, but they 

 are much more rare, have been related in 

 which the lower jaw was disproportionately 

 small. When, from either of the circumstances 



