128 OSTEOLOGY. 
is more or less convex and is directed towards the zygomatic and spheno-maxillary 
fossee. It is pierced in a downward direction by the apertures of the posterior 
dental canals (foramina 
alveolaria), two or 
more in number, which 
transmit the  corre- 
sponding nerves and 
vessels to the molar 
teeth. Its lower part, 
slightly more promi- 
Infraorbital nent where it overhangs 
foramen od : 
the root of the wisdom 
Nasal process 
Lachrymal groove. 
Lachrymal notch 
Infraorbital Orbital surface 
groove ™ 
Zygomatic 
surface molar, is often called 
the tuberosity (tuber 
Posterior 5 : \ S : 
dental= Anterior maxillare). The swpero- 
- nasal spine : 3 
canals : external or orbital sur- 
Canine fossa face (planum orbitale), 
Malar _— J F 
DrcnesEt Incisorfoss, Smooth and. plane; is 
triangular in shape and 
Alveolar 
ates process forms part of the floor 
of the orbit. Its an- 
terior edge corresponds 
to the  infraorbital 
margin; its posterior 
border coincides with 
the anterior boundary 
of the spheno-maxillary fissure. Its thin inner edge, which may be regarded as the 
base of the triangle, 1s ‘notched in front to form the lachrymal groove (sulcus lacri- 
malis), behind which it articulates with the lachrymal bone for a short distance, 
then for a greater length with the os planum of the ethmoid, and terminates 
posteriorly in a surface 
for articulation with the 
orbital process of the 
palate bone. Its ex- 
ternal angle corresponds 
to the outspring of the fhaeevor made 
zygomatic process. Tra- 
versing its substance 1s 
the infraorbital canal, the — Miadle meatus 
anterior opening of which 
Frc. 100.—RIGHT SUPERIOR MaAxILua (Outer View). 
Nasal process 
Ridge for inferior Antrum 
has been already noticed turbinated bone Va 1 
on the facial aspect of iadbeiee tent 
the body. Behind, 
however, owing to de- Rai Oh 
ficiency of its roof, the spine 
canal forms a groove 
which lips the edge of 
the bone which consti- — uittine 
tutes the anterior boun- groove 
dary of the spheno- 
maxillary fissure. If 
this canal be laid open, 
the orifices of the middle 
andanterior dental canals 
will be seen, which trans- Fia. 101.—RicHt SuPpERIOR MAXxILLA (Inner Aspect). 
mit the corresponding 
vessels and nerves to the bicuspid and incisor teeth. The inner or nasal surface 
(facies nasalis) of the body is directed inwards towards the nasal fossee. Below it is 
confluent with the upper : surface of the palatal process ; in front it is limited by the 
Posterior 
palatine 
groove 
Incisor crest 
Palatine 
process 
Alveolar 
process 
Nasal crest 
ee 
