evolve cranial bones pt 2

93. What part of the orbit does the orbital plate of the ethmoid bone form and where is its location in relationship to the nasal conchae?

Forms a small part of the medial orbital wall; located lateral to the superior and middle nasal conchae.

94. What single facial bone forms the posterior part of the nasal cavity and what bones does it articulate with and also what part is free of any bony articulation?

Vomer; articulates with ethmoid, sphenoid, maxillae, and palatine bones; posterior border is free of articulation.

95. What paired facial bones are irregular thin plates of bone that form a small part of the anterior medial wall of the orbit?

Lacrimal bones.

96. Where is the nasolacrimal duct located and what function does it serve?

Located between lacrimal bone and maxilla; drains tears from lacrimal sac into inferior nasal meatus.

97. What paired facial bones form the bridge of the nose and what opening in the skull are they superior to and also what bones do they articulate with?

Nasal bones; superior to piriform aperture; articulate with frontal, maxillae, and each other.

98. What pair of facial bones project off the maxillae to form the lateral walls of the nasal cavity and what type of bone are they composed of and also what bones do they articulate with?

Inferior nasal conchae; independent facial bones; articulate with ethmoid, maxilla, lacrimal, palatine.

99. What pair of facial bones goes to form the cheekbones and what bones do they articulate with?

Zygomatic bones; articulate with frontal, temporal, sphenoid, and maxilla.

100. What bone and its specific parts form the anterior lateral orbital wall?

Zygomatic bone and zygomatic processes of frontal and sphenoid bones.

101. What bone and its specific parts form the infraorbital rim?

Zygomatic bone and zygomatic process of maxilla.

102. What skull bone could be considered a facial bone and consists of a horizontal and vertical plate and also what bones do they articulate with?

Palatine bone; articulates with maxilla, sphenoid, ethmoid, vomer, and opposite palatine bone.

103. What plates contribute a small lip of bone to the orbital apex?

Lesser wing of sphenoid.

104. Discuss the median palatine suture and the bones involved in its formation and also what clinical landmark is it related to.

Formed by palatine processes of maxillae and horizontal plates of palatine bones; related to incisive papilla.

105. State the usual location of the greater and lesser palatine foramina and what does each transmit and also to what canals are they related to.

Greater palatine foramen near third molar; transmits greater palatine nerve/vessels; related to greater palatine canal. Lesser palatine foramina posterior to greater; transmit lesser palatine nerves/vessels; related to lesser palatine canals.

106. With which bones does the upper jaw articulate?

Frontal, zygomatic, lacrimal, nasal, vomer, palatine, ethmoid, inferior nasal concha, sphenoid.

107. What specific part of the upper jaw contains the maxillary sinuses and what are its surfaces?

Body of maxilla; surfaces: orbital, nasal, infratemporal, facial.

108. What part of the upper jaw forms a part of the medial orbital rim and with what other bones are involved in this formation?

Frontal process of maxilla; articulates with lacrimal, nasal, and ethmoid bones.

109. What landmark separates the upper jaw from the sphenoid bone and what passes through it?

Pterygomaxillary fissure; transmits maxillary artery.

110. What is the groove in the floor of the orbital surface and what canal does it become?

Infraorbital groove; continues as infraorbital canal.

111. What is the single opening on the facial surface of each side of the upper jawbone that is a landmark for a dental block and causes a mild ache when palpated?

Infraorbital foramen; landmark for infraorbital block.

112. Discuss the linear relationship of the infraorbital foramen with other surface features of the face.

Aligned vertically with pupil, supraorbital notch/foramen, and mental foramen.

113. What landmark on the upper jawbone is posterosuperior to the roots of the maxillary canine teeth?

Canine eminence.

114. What bone covers each tooth of the upper jaw?

Alveolar process of maxilla.

115. Is the facial bone of the upper jaw more or less dense than that of the facial bone of the lower jaw and what would be able to show this that is related to dentistry?

Less dense/more porous; seen on dental radiographs.

116. What opening is located on the anterior midline part of the palatine process and what does it carry and also what clinical landmark is present over it?

Incisive foramen; carries nasopalatine nerve/vessels; covered by incisive papilla.

117. What landmark is on the posterior part of the upper jaw that is a rounded roughened elevation and what perforates it?

Maxillary tuberosity; perforated by posterior superior alveolar foramina.

118. What bone is the only freely movable bone of skull?

Mandible.

119. What is the faint ridge on the external surface of the midline of the lower jaw?

Mandibular symphysis.

120. What is the bony prominence of the chin?

Mental protuberance.

121. What is the opening on the external surface of the lower jaw that is usually between the apices of the mandibular first and second premolars and what does it carry?

Mental foramen; carries mental nerve/vessels.

122. What is the heavy horizontal part of the lower jaw inferior to the mental foramen called?

Body of mandible.

123. What part of the lower jaw contains the roots of the teeth?

Alveolar process of mandible.

124. What is the stout and flat plate of the lower jaw and what does it extend upward and backward from and also what is its anterior border termed?

Ramus; extends upward/backward from body; anterior border = coronoid notch.

125. What is the concave forward curve on the anterior border of the lower jaw that serves as a landmark for a dental block?

Coronoid notch.

126. At what bony demarcation does the mandibular ramus join the body of the mandible?

Angle of mandible.

127. What depression is located between the coronoid process and the mandibular condyle?

Mandibular notch.

128. What are the small midline projections on the medial surface of the mandible and what is their function and how is the lingual foramen on each side related to them?

Genial tubercles; muscle attachment (genioglossus, geniohyoid); lingual foramen lies nearby.

129. What is the rounded roughened area on each lateral edge of the mandible that is just posterior to the most distal mandibular molar?

Retromolar triangle.

130. What landmark is located on the medial surface of the body of the mandible and what is its function?

Mylohyoid line; attachment of mylohyoid muscle.

131. What shallow depression is located just inferior to the mandibular posterior teeth and which similar depression is superior to the anterior part of the mylohyoid line?

Submandibular fossa (inferior); sublingual fossa (superior).

132. What is the opening on the medial surface of the mandibular ramus and what canal is it connected to and also what passes through it?

Mandibular foramen; connects to mandibular canal; transmits inferior alveolar nerve/vessels.

133. What bony demarcation on the mandible serves as an attachment for the sphenomandibular ligament?

Lingula.

134. What groove is near to the mandibular foramen and what travels in it?

Mylohyoid groove; transmits mylohyoid nerve/vessels.

135. What is the triangular depression on the anterior surface of the mandibular condyle?

Pterygoid fovea.

136. Discuss what happens to the sinuses when they become involved with allergies and/or infections.

Mucosa inflames → congestion, pressure, pain, impaired drainage.

137. What is an abnormal hole termed in the wall of the sinus and why does it occur?

Oroantral communication/fistula; occurs from extraction or trauma into sinus.

138. How does each frontal sinus communicate with and drain into the nasal cavity and where does it drain?

Via frontonasal duct into middle meatus through hiatus semilunaris.

139. How does each sphenoidal sinus communicate with and drain into the nasal cavity and where does it drain?

Into sphenoethmoidal recess of nasal cavity.

140. Where do the posterior ethmoid air cells open into and where do the middle and anterior ethmoid air cells open?

Posterior → superior meatus; middle/anterior → middle meatus.

141. Describe the shape of each maxillary sinus and its specific parts.

Pyramidal shape; base at nasal wall, apex at zygomatic process, roof = orbital floor, floor = alveolar process.

142. What can happen clinically because the maxillary sinus is in direct contact with the mucosa of the maxillary sinus?

Dental infection may spread to sinus; oroantral communication possible.

143. How does the maxillary sinus drain and how does the position of the ostium relate to infection?

Drains into middle meatus via ostium; ostium high in wall, making drainage difficult → risk of infection.

144. Which fossa is flat and fan-shaped on the lateral surface of the skull and what are its boundaries and also what bones form its area?

Temporal fossa; bounded by temporal lines, frontal, zygomatic, zygomatic arch; bones = frontal, parietal, temporal, sphenoid.

145. What is located in this fan-shaped depression the lateral surface of the skull?

Temporalis muscle.

146. What fossa is located inferior to the anterior part of the temporal fossa and what bones form its area and also what are its boundaries?

Infratemporal fossa; formed by maxilla, sphenoid, temporal bones; bounded by zygomatic arch, ramus, lateral pterygoid plate.

147. What structures pass through the pterygopalatine and infratemporal fossae?

Pterygopalatine → maxillary artery, V2 nerve, pterygopalatine ganglion. Infratemporal → V3 nerve, maxillary artery, pterygoid muscles.

148. What fossa of the skull is a cone-shaped depression between the pterygoid process and the maxillary tuberosity?

Pterygopalatine fossa.

149. List and describe the parts of each cervical vertebra.

Body, vertebral arch, spinous process, transverse process with transverse foramen, vertebral foramen, articular processes.

150. Which cervical vertebra articulates with the skull and what are its specific parts?

Atlas (C1); anterior/posterior arches, lateral masses, transverse processes; no body.

151. Which cervical vertebra is characterized by having a dens and what does it articulate with?

Axis (C2); dens articulates with anterior arch of atlas.

152. What bone is suspended in the neck and forms the base of the tongue and larynx and what function does it serve and also what are its specific parts?

Hyoid bone; supports tongue/larynx, aids swallowing/speech; parts = body, greater cornu, lesser cornu.

153. What are the buttress points of the skull and what can happen with severe blows to the face?

Nasomaxillary, zygomatic, and pterygoid buttresses; fractures can occur along these stress points.

154. List and further describe some variations of bone in the orofacial region that involve bony enlargement.

Tori (palatal/mandibular), exostoses, dense bone islands; benign bony enlargements.