MDS PREP
How many root canals does a madibular first molar normally have
1. 2
2. 3
3. 4
4. 5
Dental Anatomy
Answer: 2
madibular first molar normally have 3 root canals
A tooth makes its appearance in the oral cavity usually when
1. all of the crown is completed
2. all of the root is completed
3. one half of the root is completed
4. one half of the crown is completed
Dental Anatomy
Answer: 3
A tooth makes its appearance in the oral cavity usually when one half of the root is completed
Primary teeth begin to calcify between the ________ and ________months in
utero.
1) first; second
2) second; fourth
3) fourth; sixth
4) sixth; eighth
The primary teeth begin to form in utero at about six weeks. Hard tissue
formation occurs in all primary teeth by the 18th week in utero. 3. The
permanent teeth begin to develop at approximately four months of age in utero.
Maxillary and mandibular first molars begin to calcify at birth.
Malformation of the coronal portion of the permanent anterior teeth is most frequently encountered in the
1. maxillary central incisor
2. maxillary lateral incisor
3. maxillary canine
4. mandibular lateral incisor
Dental Anatomy
Answer: 2
Maxillary lateral incisor agenesis:
This is the most common congenital absence of a permanent tooth in the maxillary
anterior region, accounting for about 20% of all dental anomalies.
Coronal developmental invagination (DI):This is a common anomaly in the
permanent maxillary lateral incisor, usually appearing as an accentuation of the
lingual pit.It's often bilateral.
Peg-shaped crown:This is a common alteration in the maxillary lateral incisor.
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
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 secretory product of odontoblasts is:
1) Topocollagen.
2) Calcium salts.
3) Mantle dentin.
4) Hydroxyapatite
Dental Anatomy
Answer: 3
Dentinogenesis is the formation of dentin by odontoblasts of mesenchymal origin
located at the periphery of the dental pulp
Dentinogenesis is initiated by the inductive influence of the enamel organ
involving molecular signaling pathways, such as Wnt, Runx-2, and TGF-?. In the
molar tooth, dentinogenesis starts at the late bell stage, and occurs in the
crown as well as root regions.
Predentin, the first organic matrix secreted by odontoblasts, is composed by
proteoglycans, glycoproteins, and collagens.
During eruption of permanent teeth, alveolar bone is
1. deposited only
2. resorbed only
3. resorbed and deposited intermittently
4. neither resorbed nor deposited
Dental Anatomy Answer: 3
During eruption of permanent teeth, alveolar bone is resorbed and deposited intermittently