Test Bank Illustrated Dental Embryology Histology and Anatomy 5th Edition by Margaret Fehrenbach, Tracy Popowics

Test Bank Illustrated Dental Embryology Histology and Anatomy 5th Edition by Margaret Fehrenbach, Tracy Popowics Chapter 04: Face and Neck Development MULTIPLE CHOICE 1. The medial nasal processes are involved directly in the formation of the embryo’s _____ of the nose during prenatal development. a. bridge b. sides c. bridge and sides d. nasal placodes ANS: A The medial nasal processes refer to the middle part of the tissue growing around the nasal placodes, and they appear as two crescent-shaped swellings located between the nasal pits. In the future, the medial nasal processes will fuse together externally to form the middle part of the nose from the root of the nose, including the bridge of the nose, to the apex of the nose, as well as the tubercle of the upper lip and philtrum. REF: Chapter 4, Nose and Paranasal Sinus Formation, Page 36 2. The philtrum of the upper lip forms during sixth week of prenatal development from the: a. mandibular processes. b. medial nasal processes. c. lateral nasal processes. d. nasal placodes. ANS: B During the start of the sixth week of prenatal development, the upper lip begins formation when each maxillary process fuses with each medial nasal process on both sides of the stomodeum. Thus, the maxillary processes contribute to the sides of the upper lip, and the two medial nasal processes contribute to the philtrum. REF: Chapter 4, Upper and Lower Lip Formation, Page 37 3. The mandibular arch during the embryonic period of prenatal development is the: a. fusion of the two paired mandibular processes. b. swelling found superior to the stomodeum. c. structure that gives rise to the lateral nasal process. d. posterior part of the hard palate. ANS: A The paired mandibular processes then fuse at the midline to form the mandibular arch, the developmental form of the future lower dental arch, the mandible. After fusion, the mandibular arch then extends as a band of tissue found inferior to the stomodeum and between the developing brain and heart. REF: Chapter 4, Mandibular Arch and Lower Face Formation, Page 34 4. A type of cleft lip can result during prenatal development from the lack of fusion between _____ processes. a. mandibular and maxillary b. medial nasal and maxillary c. lateral nasal and medial nasal d. two lateral nasal e. lateral nasal and maxillary ANS: B Failure of fusion of the maxillary process with the medial nasal process can result in cleft lip, with varying degrees of disfigurement and disability present in the upper lip. REF: Chapter 4, Clinical Considerations for Upper Lip Development, Page 37 5. In which week of prenatal development does facial development begin in the embryo? a. Second b. Fourth c. Fifth d. Eighth ANS: B The face and its associated tissue begin to form during the fourth week of prenatal development within the embryonic period. REF: Chapter 4, Facial Development, Page 32 6. Which of the following facial structures is formed from the mandibular arch during prenatal development? a. Forehead b. Lower face c. Philtrum d. Nose ANS: B In the future, the mandibular arch directly gives rise to the lower face, including the lower lip. The mandibular arch will also give rise not only to the mandible, but additionally to its mandibular teeth and associated tissue. REF: Chapter 4, Mandibular Arch and Lower Face Formation, Page 34 7. Which of the following phrases concerning the second branchial arch during prenatal development is correct? a. Called the mandibular arch b. Contains Reichert cartilage c. Forms into the muscles of mastication d. Associated with the trigeminal nerve ANS: B Forming within the second branchial arch, or hyoid arch, is cartilage similar to that of the mandibular arch, Reichert cartilage. Most of it disappears during development; however, parts of it are responsible for a middle ear bone, a process of the temporal bone, and parts of the hyoid bone. The mesoderm of the hyoid arches helps form the muscles of facial expression, the middle ear muscles, and a suprahyoid muscle. Because these muscles are derived from the hyoid arches, these structures are all innervated by the nerve of the second arches, which is the facial nerve or seventh cranial nerve. REF: Chapter 4, Branchial Apparatus Formation, Page 38 8. From which structure during prenatal development is the palatine tonsillar tissue derived? a. First branchial arches b. First pharyngeal pouches c. Second branchial arches d. Second pharyngeal pouches ANS: D The palatine tonsils are derived from the lining of the second pharyngeal pouches and also from the pharyngeal walls. REF: Chapter 4, Branchial Apparatus Formation, Page 41 9. The frontonasal process is a swelling that appears over the developing brain in the embryo during prenatal development and forms the future: a. forehead. b. otic placodes. c. mandibular arch. d. neck area. ANS: A During the fourth week, the frontonasal process also forms as a bulge of tissue at the most cephalic end of the embryo and is the cranial boundary of the stomodeum. In the future, the frontonasal process gives rise to the upper face, which includes the forehead, bridge of the nose, primary palate, nasal septum, and all structures associated with the medial nasal processes. REF: Chapter 4, Frontonasal Process and Upper Face Formation, Page 35 10. Which of the following tissue usually uses both interstitial and appositional growth to attain its final size? a. Hard dental tissue b. Mature bone c. Cartilage d. Gingival tissue ANS: C During the growth of the mandibular arch, Meckel cartilage forms within each side of the arch. Most of this cartilage disappears as the bony mandible forms by intramembranous ossification lateral to and in close association with the cartilage; yet only some small part makes a contribution to it. This process in cartilage uses both interstitial and appositional growth to attain its final size. REF: Chapter 4, Mandibular Arch and Lower Face Formation, Page 34 11. Which of the following statements concerning facial development is correct? a. The face and its related tissue begin to form during the sixth week of prenatal development. b. The overall growth of the face is in a superior and posterior direction in relationship to the cranial base. c. All three embryonic layers are involved in facial development. d. The paired maxillary processes fuse at the midline to form the mandibular arch. ANS: C All three embryonic layers are involved in facial development. The face and its related tissue begin to form during the fourth week of prenatal development. The overall growth of the face is in an inferior and anterior direction in relationship to the cranial base. Paired mandibular processes then fuse at the midline to form the mandibular arch. REF: Chapter 4, Facial Development, Page 32 12. The _____ are rounded areas of specialized, thickened ectoderm found at the location of developing special sense organs. a. placodes b. branchial arches c. branchial pouches d. processes ANS: A The placodes are rounded areas of specialized, thickened ectoderm found at the location of developing special sense organs. During the fourth week of prenatal development, stacked bilateral swellings of tissue called the branchial arches appear inferior to the stomodeum and include the mandibular arch. Four well-defined pairs of pharyngeal pouches develop as endodermal evaginations from the lateral walls lining the pharynx. Facial development depends on five major facial processes that form during the fourth week and surround the primitive mouth of the embryo: single frontonasal process and paired maxillary and mandibular. REF: Chapter 4, Placode Development, Page 35 13. The facial development that starts in the fourth week will be completed later in the _____ week within the fetal period. a. fifth b. sixth c. eighth d. twelfth ANS: D The facial development that starts in the fourth week will be completed later in the twelfth week within the fetal period. REF: Chapter 4, Facial Development, Page 32 14. How many processes are considered major during facial development so that they become the centers of growth for the face? a. Two b. Three c. Four d. Five ANS: D Facial development depends on the five major facial processes that form during the fourth week and surround the primitive mouth of the embryo: single frontonasal process and paired maxillary and mandibular processes. Thus, these facial processes become the centers of growth for the face. REF: Chapter 4, Facial Development, Page 32 15. Which of the following marks the end of the major growth of the lower two thirds of the face? a. The forehead ceases to grow significantly after age 12. b. The eruption of the permanent third molars, which occurs at approximately 17 to 21 years of age. c. The midface and lower face grow more slowly over a prolonged period of time and finally cease to grow late in puberty. d. The brain ceases its rapid development along with the growth of the upper face. ANS: B In contrast, the eruption of the permanent third molars at approximately 17 to 21 years of age marks the end of the major growth of the lower two thirds of the face. The growth of the upper face is initially the most rapid, in keeping with its association with the rapidly developing brain. Subsequently, the forehead ceases to grow significantly after age 12. REF: Chapter 4, Facial Development, Page 33 16. What is the first event in the development of the face during the later part of the fourth week of prenatal development? a. Disintegration of the oropharyngeal membrane b. Paired mandibular processes fusion at the midline to form the mandibular arch c. Folding of the embryonic structure into a tubal one d. Thickening of the facial placodes ANS: A The first event in the development of the face during the later part of the fourth week of prenatal development is disintegration of the oropharyngeal membrane. With this disintegration of the membrane, the primitive mouth increases in depth and enlarges across the surface of the midface. REF: Chapter 4, Stomodeum and Oral Cavity Formation, Page 34 17. What does the maxillary process form from during the fourth week of prenatal development? a. Lateral nasal processes b. Mandibular arch c. Intermaxillary segment d. Medial nasal processes