DENT 1020 Oral Embryology (Ch. 6, 15) Flashcards
The dental sac will form the: A) Epithelial rests of Malassez B) Secondary dental lamina C) Periodontal ligament D) All of the above
C) Periodontal ligament
Which of the following embryonic structures becomes the dentinoenamel junction?
A) Inner cells of the dental papilla
B) Outer cells of the dental papilla
C) Inner enamel epithelium of the enamel organ
D) Disintegrating basement membrane
D) Disintegrating basement membrane
Cementoblasts undergo cementogenesis laying down \_\_\_\_\_? A) Cementoid B) Cementoblasts C) Cementocytes D) Pre Cementum
A) Cementoid
A patient has supernumerary molars distal to her third molars. These additional molars are the product of escessive inductions of the: A) Dental sac B) Enamel organ C) Primary dental lamina D) Secondary dental lamina E) Reduced enamel epithelium
C) Primary dental lamina
The developmental disturbances that result in: dens in dente, gemination, and fusion are created during which stage of tooth development? A) Initiation stage B) Bud stage C) Cap stage D) Bell stage E) Apposition stage
C) Cap stage
Which of the following is formed by the cells of the enamel organ at its most cervical point and will guide root formation? A) Dental sac B) Enamel cuticle C) Epithelial rests of Malassez D) Hertwig's epithelial root sheath
D) Hertwig’s epithelial root sheath
The reduced enamel epithelium (REE) will form the primordium of which structure(s)? A) Cementoblasts B) Lamina dura of the bone C) Periodontal ligament D) Junctional epithelium E) All of the above
D) Junctional epithelium
Dentinogenesis begins after which of the following occur?
A) Preameloblasts differentiate into ameloblasts
B) Basement membrane disintegrates
C) IEE cells repolarize
D) All of the above
C) IEE cells repolarize
During which stage is the primordium of the tooth (a.k.a. "tooth germ") first manifest? A) Induction B) Bud C) Cap D) Bell E) Apposition
C) Cap
Which of the following is NOT a component of the tooth germ? A) Dental lamina B) Dental papilla C) Dental sac D) Enamel organ
A) Dental lamina
During the process of tooth eruption the REE performs which of the following functions?
A) It fuses with the oral epithelium
B) It releases enzymes to help disintegrate the oral epithelium
C) It peels off coronally allowing the tooth to “erupt”
D) It remains attached at the CEJ (cervix) maintaining a temporary seal
E) All of the above
E) All of the above
Which of the following pairs does NOT represent a true embryologic relationship? A) Epiblast -> Ectoderm B) Hypoblast -> Endoderm C) Ectoderm -> Enamel D) Hypoblast -> Mesenchyme
D) Hypoblast -> Mesenchyme
Of the three primary embryonic layers, the one that will form the dentin and pulp is the:
A) Ectoderm
B) Endoderm
C) Mesoderm
C) Mesoderm
Teeth are formed from which of the following embryonic tissues? A) Endoderm and ectoderm B) Ectoderm and mesenchyme C) Endoderm and mesenchyme D) Ectoderm, mesenchyme, and endoderm
B) Ectoderm and mesenchyme
Hertwig’s epithelial root sheath is entirely composed of:
A) All layers of the enamel organ
B) Enamel organ and dental papilla
C) Inner and outer cells of the dental papilla
D) Inner and outer enamel epithelium
E) Dental sac and dental papilla
D) Inner and outer enamel epithelium
Which of the following PERMANENT teeth are formed by the secondary dental lamina? A) Incisors B) Canines C) Premolars D) Molars E) A, B, and C
E) A, B, and C
The extensions of the primary dental lamina into the mesenchyme form cap-like structures (cap stage). A) Tooth germ B) Enamel organ C) Dental papilla D) Secondary dental lamina
B) Enamel organ
The outer cells of the dental papilla are induced to differentiate into: A) Pulp tissue B) Preameloblasts C) Odontoblasts D) Cementoblasts E) Ameloblasts
C) Odontoblasts
The enamel organ is composed of four layers of cells. The cells that will eventually differentiate into ameloblasts are the cells of the: A) Stellate reticulum B) Outer enamel epithelium C) Inner enamel epithelium D) Reduced enamel epithelium
C) Inner enamel epithelium
The cellular extensions of the Odontoblasts that remain attached to the basement membrane as dentin forms are called: A) Enamel spindles B) Dentinal fibrils C) Dentinal tubules D) Odontoblastic processes
D) Odontoblastic processes