Facies orbitalis 



Sulcus infraorbitalis 

 Facies infratemporalis 



Foramina alveolaria -. 

 Tuber maxillare - 



Processns 

 zygomaticus 



Processus frontalis 



.__ Crista lacrimalis anterior 



- Incisura lacrimalis 



Margo infraorbitalis 

 Facies anterior 



Foramen infraorbitale 

 Fossa canina 

 Incisura nasalis 

 _, Processus palatinus 



Spina nasalis anterior 

 Juga alveolaria 



Processns 

 alveolaris 



34. Right upper jaw bone, maxilla, from without. 



The maxilla (0. T. superior maxillary bone) (see also Pigs. 35, 36, 55 60, 6775) 

 is paired, lies in the upper anterior part of the facial skull and is divisible into a corpus or 

 body and four processes of which two, the processus frontalis and processus zygomaticus, 

 belong to the upper part, while the two others, the processus alveolaris and the processus 

 palatinus, belong to the lower part. 



The corpus or body (see also Figs. 35, 36, 5558 and 6772) is quadrangular in 

 shape and contains within it a large cavity, sinus maxillaris (0. T. antrinn of Highmore) 

 lined by mucous membrane, the entrance to which, hiatus maxillaris, is situated on the nasal 

 surface. The upper surface, fades orbitalis (planum orbitale) is smooth, triangular, directed 

 obliquely forward, outward and downward and forms the floor of the orbit; its medial border 

 unites behind with the lamina papyracea oss. ethmoid, (sutura ethmoideomaxillaris) , in front 

 with the lachrymal bone (sutura lacrimomaxillaris) the anterior border is smooth median- 

 ward, lying free as the mar go infraorbitalis, while lateralward it is serrated and goes over 

 into the proc. zygomaticus; the posterior border is for the most part smooth, lies free, and 

 forms with the inferior margin of the orbital surface of the large wing of the sphenoid running 

 parallel to it, the fissura orbitalis inferior (for the a. infraorbit., v. ophthalm. inf. ; nn. zygomat., 

 infra orbit.). From this point forward on the upper surface extends a groove (sulcus infra- 

 orbitalis) closed by periosteum, which gradually becomes deeper and is continued into the 

 canalis infraorbitalis (both for the a. infraorbit.; n. infraorbit.); branching off from this are 

 the very minute canales alveolares (for the aa. alveol. sup. ant. ; IT. alveol. sup. medius et 

 anteriores n. infraorbit.), which run within the anterior wall of the body of the bone. Upon 

 and beneath the posterior medial angle of the facies orbitalis is attached the proc. orbital, oss. 

 palat. (sutura palatomaxillaris). The posterior surface, facies infratemporalis (0. T. zygo- 

 matic surface), looks into the fossa imfratemporalis and pterygopalatina, is slightly rough, often 

 bulged out (tuber maxillare) and there gives origin to parts of the mm. pterygoideus externus 

 and internus; it presents from two to three small openings, foramina alveolaria, which lead 

 into canals passing forward, the canales alveolares (0. T. posterior dental canals) (for the a. 

 alveol. sup. post.; nn. alveol. sup.). The anterior surface, facies anterior (0, T. external or 

 facial surface), presents above the foramen infraorbitale, the opening of exit of the canalis 

 infraorbit.; beneath it a variable depression, fossa canina (for the m. caninus). There arise 

 also in front several muscles, the caput infraorbit. m. quadrat, labii sup., m. nasalis, m. incisivus, 

 in. buccinat. Medianward the facies anterior runs out into a sharp margin, the incisura nasalis. 



