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ANATOMY AND PHYSIOLOGY OP 



bone has a facial, palatine, and nasal sur- 

 face. It has also nasal, alveolar, and pala- 

 tine borders, and two extremities : posterior, 

 which forms the maxillary tuberosity ; 

 anterior, or dental extremity. 



Q. "What are the connections of the ossa 

 maxilaria ? — A. With the squamous tem- 

 poral, nasal, anterior maxillary, malar, 

 laclirymal, palate, and inferior turbinated 

 bones. 



ANTERIOR MAXILLARY BONES (oSSA MAXIL- 

 LARIA ANTERIORa). 



Q. What is the situation of these bones? 

 — A. They are placed in the supero-anterior 

 and antero-lateral parts of the face. 



Q. What is the general form of these 

 bones ? — A. Very irregular ; consisting of 

 a broad, thick base, turned forwards, from 

 which is sent off a thin flexible plate ; and 

 a narrow, elongated, tapering portion 

 turned backwards. 



Q. How is each bone divided ? — A. Into 

 three surfaces and three borders. 



Q. Describe the surfaces. — A. The 

 superior or nasal surface is smooth, con- 

 vex, and oblong. The inferior or palatine 

 is vaulted, it contributing to the formation 

 of the palate ; within it, of an oval form, is 

 the interdental space, which is occupied by 

 two thin, flexible plates, the palatine pro- 

 cesses, denticulating along the sides with 

 each other. In the side of the bone is a 

 deep hollow, for the reception of that por- 

 tion of the superior maxillary bone which 

 holds the tusk ; and the remainder of the 

 surface, posteriorly, is articulated with the 

 same. The anterior or labial surface is 

 broad, smooth, and convex, and gives at- 

 tachment to the depressor labii superioris, 

 and gums. 



Q. Describe the borders. — A. The 

 anterior border is broad and curved, and is 

 composed of two laminae, formed apart and 

 divided into septa for the insertion of six 

 incisors. The posterior border is narrow 

 and sloped, and denticulates with the nasal 

 bone. The internal border is broad, 

 quadrilateral, curved, and denticulates with 

 its fellow, forming thereby the superior 



maxillary symphysis, through which runs 

 the foramen incisivum, for the transmission 

 of the palatine arteries. 



Q. How is this bone connected? — A. 

 It connects with the superior maxillary and 

 nasal bones, and with its fellow. 



MALAR BONES (oSSA MALARUM). 



Q. What is the situation of the ossa 

 malarum? — A. They occupy the antero- 

 external part of the orbit. 



Q. Describe their form. — A. Irregularly 

 triangular, presenting a broad basis forwards. 



Q. How is the bone divided ? — A. Into 

 three surfaces, three angles, a basiform and 

 an apiform extremity. 



Q. Name the surfaces. — A. Facial, 

 maxillary, and orbital. 



Q. Describe the same. — A. The facial 

 surface is divided into two portions by the 

 zygomatic spine ; the upper division is 

 smooth and nearly flat; the lower part is 

 narrow and roughened, for the insertion of 

 the masseter muscle. From this surface, 

 posteriorly, arises the zygomatic process, 

 which is very obliquely sloped off, and 

 laminated for adaptation to the process 

 of the same name, meeting it from the tem- 

 poral bone, the two together forming the 

 zygomatic arch. The maxillary surface is 

 concave. The orbital surface has a smooth 

 concavity which forms the infero-external 

 part of the orbit. 



Q. Describe the angles. — A. There are 

 three, superior, inferior, and posterior. The 

 superior constitutes the external portion of 

 the orbital circumference. The inferior 

 forms the zygomatic spine. The posterior 

 is not so prominent nor defined, but forms 

 an irregular link with the superior maxillary 

 bone. 



Q. What of the extremities ?— ^1. The 

 anterior extremity is broad, irregular, and 

 denticulated, and articulates with the supe- 

 rior maxillary and lachrymal bones. The 

 posterior or apiform extremity forms the 

 zygomatic process. 



Q. With what bones do the ossa mala- 

 rum connect ? — A. With the temporal, 

 superior, maxillary, and lachrymal bones. 



