MDS PREP
Temporalis muscle is inserted into:
1. lip and lateral surface of coronoid
2. Tip and medial surface of coronoid
3. Tip and anterior border of coronojd upto external oblique ridge
4. B and C
Anatomy
Answer: 2
Temporalis muscle is inserted into Tip and medial surface of coronoid
The primary mandibular central incisors usually erupt at
1. 6-8 months
2. 2 years
3. 10 - 13 months
4. 52 - 72 weeks
Dental Anatomy
Answer: 1
The primary mandibular central incisors usually erupt at 6-8 months
The beginning of active eruption of a human tooth occurs
1. before the root has begun to develop
2. coincidental with the beginning of root formation
3. before the root has begun to develop
4. after one half of the root is formed
Dental Anatomy
Answer: 4
The beginning of active eruption of a human tooth occurs after one half of the root is formed
When calcospherites fail to fuse during calcification of dentin matrix then
1 Interglobular dentin is formed
2 Dead tracts are found in formed dentin
3 Irregular dentin results
4 None
Dental Anatomy Answer: 1
Interglobular Dentin:
Sometimes, mineralization of dentin begins in small globular areas that fail to coalesce into a homogenous mass. This results in zones of hypomineralization between the globules.
These zones are known as globular dentin or interglobular spaces. Thus, demonstrating defect of mineralization and not of matrix formation, the dentinal tubules pass uninterruptedly through interglobular dentin.
The nerve to masseter passes
1. deep to the medial pterygoid muscle
2. posterior to temporomandibular joint
3. superior to zygomatic arch to enter the muscle on its medial surface
4. through the mandibular notch to enter the muscle on its medial surface
Anatomy
Answer: 4
The nerve to masseter passes through the mandibular notch to enter the muscle on its medial surface
The nerve to the masseter muscle is the masseteric nerve, which is a branch
of the mandibular nerve (CN V3), the largest division of the trigeminal nerve
(cranial nerve V). The masseter muscle is one of the muscles of mastication that
lifts the lower jaw, contributing to the action of biting and chewing.
The masseteric nerve originates from the anterior division of the mandibular
nerve and typically passes:
1. Deep to the medial pterygoid muscle: The medial pterygoid muscle is located
in the infratemporal fossa, which is the space deep to the zygomatic arch and
medial to the temporomandibular joint (TMJ). The masseteric nerve runs in a deep
position relative to the medial pterygoid muscle as it travels towards the
masseter muscle. This muscle is involved in the side-to-side movement of the
jaw, known as lateral excursion.
2. Posterior to the temporomandibular joint: The TMJ is the articulation between
the mandible and the temporal bone of the skull. It is a synovial joint that
allows for the hinge movement of the jaw, such as opening and closing the mouth.
The masseteric nerve passes behind the TMJ to reach the masseter muscle. This
nerve does not actually cross the joint itself but runs in a position posterior
to it.
3. Superior to the zygomatic arch: The zygomatic arch is the bony structure that
extends from the zygomatic process of the temporal bone to the zygomatic bone of
the skull. It forms the prominence of the cheek. The masseteric nerve runs
superior to the zygomatic arch to reach the masseter muscle. The arch serves as
a landmark for the nerve's course, and the nerve typically does not pass through
the arch itself.
4. Through the mandibular notch: This statement is not entirely correct. The
masseteric nerve does not pass through the mandibular notch, which is a
depression on the medial surface of the ramus of the mandible, but rather it
passes above (superior to) the notch. The mandibular notch is the location where
the masseteric nerve and the other branches of the mandibular nerve leave the
infratemporal fossa and enter the submandibular space to innervate the muscles
of mastication, including the masseter. The nerve then runs along the lateral
surface of the lateral pterygoid plate and enters the deep surface of the
masseter muscle.
In summary, the masseteric nerve passes deep to the medial pterygoid muscle,
posterior to the TMJ, and superior to the zygomatic arch. It does not pass
through the mandibular notch; instead, it runs superior to it before reaching
the masseter muscle. The anatomical pathway of this nerve allows it to
effectively innervate the masseter muscle, which is crucial for the function of
the muscle in mastication.
The palatine bone articulates with all of the following except
1.sphenoid
2. ethmoid
3. zygomatic
4. vomer
Anatomy Answer: 2
The palatine bone articulates with all of the following except a.sphenoid b. ethmoid c. zygomatic d. maxilla
A wound to the posterior left axillary line, between the ninth and tenth rib, and extending approximately 5 cm deep, will most likely damage which organ?
1) Ascending colon
2) Duodenum
3) Left kidney
4) Spleen
Anatomy
Answer: 4
The spleen follows the long axes of ribs 9 to 11 and lies mostly posterior to the stomach, above the colon, and partly anterior to the kidney. It is attached to the stomach by a broad mesenterial band, the gastrosplemic ligament. Therefore, it is the most likely organ of the group to be pierced by a sharp object penetrating just above rib 10 at the posterior axillary line. Note that the pleural cavity, and possibly the lower part of the inferior lobe of the lung, would be pierced before the spleen. The ascending colon (choice 1) is on the wrong side (the right) to be penetrated by a sharp instrument piercing the left side.
Most of the duodenum (choice 2) is positioned too far to the right to be affected by this injury.
Even the third part of the duodenum, which runs from right to left, would still be out of harm's way. In addition, the duodenum lies at about levels L1 to L3, placing it too low to be injured in this case.
The superior pole of the left kidney (choice 3) is bordered by the lower part of the spleen. However, it is crossed by rib 12 and usually does not extend above rib 11. It would probably be too low and medial to be injured in this case because this penetration is at the posterior axillary line.
A permanent tooth erupting in the mouth of an 11 years old child is most likely
1. maxillary lateral incisor
2. mandibular second bicuspid
3. maxillary third molar
4. rnandibular central incisor
Dental Anatomy
Answer: 2
A permanent tooth erupting in the mouth of an 11 years old child is most likely mandibular second bicuspid