Prenatal Development of the Human with Special Reference to Craniofacial Structures: An Atlas Sponsored by National Institute of Dental Research U.S.A. Authors Hideo Nishimura Reiji Semba Takashi Tanimura Osamu Tanaka Prepared under auspices of Central Institute for Experimental Animals Kawasaki, Japan (Director: Tatsuji Nomura, M.D., Dr. Med. Sci.) DHEW Publication No. (NIH) 77-946 U.S. Department of Health, Education, and Welfare Public Health Service National Institutes of Health Bethesda, Maryland 20014 1977 Authors Hipeo NisuiMura, M.D., Dr. MED. Scr. Professor Emeritus (Anatomy), Faculty of Medicine Kyoto University, Kyoto and Staff Scientist, Central Institute for Experimental Animals Kawasaki, Japan Reyr Sema, M.D.. Dr. MED. Sci Institute for Developmental Research Aichi Prefectural Colony Kasugai, Aichi, Japan Taxasul Tanimura, M.D., Dr. MED. Scr. Department of Anatomy, Faculty of Medicine Kyoto University, Kyoto, Japan and Osamu Tanaka, M.D., Dr. MEp. Sci. Department of Anatomy, Faculty of Medicine Kyoto University, Kyoto, Japan Technical assistance Tosuiakl Nagar (Photography) Cuicako Uwase (Microdissection) HaTrsumr FukusaiMa (Dissection) AsaE Kawakami (Histology) For sale by the Superintendent of Documents, U.S. Government Printing Office Washington, D.C. 20402 — Price $6.90 Stock No. 017-047-00010-8 Foreword Much progress has been made in techniques to repair congenital craniofacial malformations, particularly in children. As habilitative efforts continue, it is increasingly appreciated that prevention of disfigurements must be the final goal. To investigate etiologic factors, research proceeds in many directions: human genetic and cytogenetic studies, environmental research, and teratologic experi- mentation. In recent times the importance of morphologic investigations of human development has received less emphasis. Yet, without thorough knowledge of the basic facts of prenatal human development, erroneous assumptions can be made in more dynamic approaches and lead investigators astray. Morphologic details may be quite important not only in etiologic research but also in the treatment of congenital malformations. Additions to the knowledge of prenatal development of human oral-facial structures and some of their devia- tions will therefore be welcomed by many basic scientists and clinicians in the field of facial clefts and other craniofacial malformations such as orbital hyper- telorism. This Atlas represents a distinct contribution to our knowledge of craniofacial embryology. The material contributing to the Atlas was obtained from both induced abortions and stillbirths. While many of the induced abortions were performed for therapeutic reasons, the majority of the specimens were obtained under the Japanese Eugenics and Maternal Protection Law. Subsequently this law has been amended to limit abortion to cases with therapeutic indications. This law made it possible to collect human embryos and fetuses that had developed normally to the late stage. Thus, a unique opportunity was presented for a large-scale study of normal, and sometimes abnormal, human development. Professor Nishimura and his coworkers have made use of these products of legal abortion in the Atlas on Prenatal Development of the Human with Special Reference to Craniofacial Structures. Since induced abortion was not permitted in the last trimester of pregnancy, late stages of development shown in the Atlas are from stillborn fetuses with little postmortem changes. Other works deal with successive stages of the developing human embryo, but they do not emphasize and illustrate specifically the craniofacial structures. In addition, there are good illustrations of various stages of the face and palate in textbooks of embryology, but they do not follow serially all the changes that lead to the formation of the human face. The present Atlas supplements these pub- lications by serial illustrations of craniofacial development. The Atlas of Developmental Anatomy of the Face published in 1966 by Kraus, Kitamura and Latham illustrates the craniofacial structures of normal embryos and fetuses from age 35 days to the newborn; it also shows specimens with facial clefts from 41 days to full term. The aborted specimens had been ( ps WW 602 P1731 PUBL iii iv gathered from 250 hospitals in various regions of the United States and from several institutions in Japan. One of the aims was to demonstrate natural varia- tions by showing three specimens for each age among the so-called normals or controls. The authors realized that normality was problematic in their material since it consisted of spontaneous abortuses, “a population that failed for one reason or another to survive.” Thus, normality could not be assumed with cer- tainty. In fact, many sections show signs of postmortem changes so that detailed histologic evaluation is at times impossible. Professor Nishimura’s Atlas is there- fore a welcomed addition to the existing knowledge because of the excellent state of the undamaged and well-preserved specimens. Embryos were classified accord- ing to Streeter’s horizons or the Carnegie system; fetuses were presented according to crown-rump length. Some pathologic fetuses with oral-facial or other malforma- tions were added. Roentgenograms and photographs showing the external appear- ance of the fetuses, of histologic sections, and of cleared specimens were sup- plemented by carefully drawn and annotated diagrams which interpret the objec- tive presentations. Appendix references to books, reviews and original articles dealing with oral-facial development will further aid the user of the Atlas. The fact that the bibliography is international should be of particular value to the English-speaking reader. This Atlas will remain a standard work for many years to come. JoseEF WARKANY Children’s Hospital Research Foundation Cincinnati, Ohio Preface An embryological approach with human materials is important for establish- ing a normal standard of development including individual variabilities as well as clarifying the embryogenesis and etiology of defective development. It has been difficult, however, to obtain a sequential series of specimens in proper condition, and most of the current knowledge in this respect has been derived from a limited number of specimens arising mostly from pathological pregnancy. In view of this, the authors undertook a 12-year systematic study of normal and abnormal devel- opment with a large number of embryonic and fetal specimens obtained under the Eugenics and Maternal Protection Law of Japan from normal pregnancies with the assistance of hundreds of obstetricians. The specimens from induced abortions were supplemented with a number of selected specimens of stillborn fetuses and neonatally dead infants for study of the perinatal stage. This long-term experience convinced the authors of the need for as well as the feasibility of preparing a complete pictorial monograph on normal and abnormal development of oral- facial structures. Thus, a proposal for this contract was submitted to and approved by the National Institute of Dental Research. The 2-year study, conducted in collaboration with the Central Institute for Experimental Animals and the De- partment of Anatomy, Faculty of Medicine, Kyoto University, made possible the completion of this work. This monograph, presenting the detailed photographs of stages of normal and defective development of the oral-facial complex, will furnish dentists, oral surgeons and other biomedical scientists with reliable standards for embryological and teratological studies. Contract No. NIH-NIDR-73-2405 (NOI-DE-32405) vi Acknowledgement We are deeply grateful to Dr. K. K. Hisaoka and Dr. R. L. Christiansen of the National Institute of Dental Research, and Dr. R. L. Woolridge of the National Cancer Institute, National Institutes of Health, U.S.A., for their kind advice in planning and conducting the project; to numerous collaborating obstetricians for their cooperation in securing the specimens; to Dr. N. Iwahori, Department of Anatomy, Faculty of Medicine, Kyoto University, and Mr. B. Wongchoawant, medical student at the University, for their aid in preparation of the brain speci- mens; to Mr. M. Kawabata, Institute for Developmental Research, Aichi Prefec- tural Colony, for his assistance in X-ray photography; and to Miss Y. Ohta, Central Institute for Experimental Animals, and Miss K. Hirai, Department of Anatomy, Kyoto University, for their secretarial assistance. Also, appreciation is expressed to Dr. A. G. Hendrickx, National Center for Primate Biology, Univer- sity of California, Davis, for his linguistic help during his visiting Professorship at Kyoto University. Outline of the Work Specimens The specimens used for this study were selected cases from the human em- bryonic collection in the Department of Anatomy, Faculty of Medicine, Kyoto University. This collection, consisting of about 30,000 specimens at stages rang- ing from about the third week of gestation to term, was established in collabora- tion with about 800 obstetricians located in the central area of Japan. The Eugenics and Maternal Protection Law in Japan allowed qualified obstetricians to terminate pregnancy at and before the seventh month at the request of both the expectant mother and her spouse for socioeconomic reasons. According to official statistics, in most instances abortion was induced in the second and third month of pregnancy. Cervical dilation and curettage were performed in the second to approximately the fourth month of pregnancy. Occasionally, from about the fifth to the seventh month, delivery was induced by means of bougie or metreurynter. The obstetricians were thus able to provide undamaged embryos (approximately 30 mm in crown-rump length or less) and early fetuses (approxi- mately between 30 mm and 200 mm in crown-rump length). In addition, they furnished a small number of undamaged stillborn fetuses at and after the eighth month of pregnancy, as well as neonatally deceased infants. It should be empha- sized that the attempt to collect specimens had no bearing on the determination of abortion by both the expectant mother and the obstetrician. Further, only those fetal and neonatal specimens were acquired whose dissection and preserva- tion were authorized in writing by the mother with no objection of her spouse. The obstetricians usually fixed the embryos in Bouin's fluid immediately after acquisition and transferred them to 109, formalin solution the next day. In the case of fetuses, the obstetricians used 109] formalin solution for fixation and storage; occasionally appropriate incisions in the body wall were made prior to fixation. Specimens obtained by obstetricians in and around Kyoto City were brought to the Department of Anatomy, Kyoto University immediately after their recovery. Others were brought in periodically. All specimens were accompanied by a record form completed by the obstetricians. This record form included such items as parental ages, consanguinity, parity, period after previous pregnancy, frequency of past pregnancy wastage and induced abortion, history of the use of contraceptive measures, parental occupation, habits of smoking and drinking, and history of maternal diseases and medical treatments. Procedures Appropriate undamaged specimens with no or little postmortem change were selected and their crown-rump length was measured. Careful examination of their external developmental stages was then made under a stereomicroscope or macro- scopically. The numerical stage of the embryonic specimens was determined by adopting the Streeter’s horizon system!) or the Carnegie system proposed by O’Rahilly?). The existence of external malformations as well as those in the oral cavity was also checked. The procedures were as follows: vii viii Externally normal specimens: The occurrence of distinctly recognizable developmental features, such as the appearance of each branchial arch, auditory vesicle, buccopharyngeal membrane, medial and lateral nasal swelling, maxillary swelling, hypophyseal pouch, opening of auditory tube, external auditory pore, auricular hillocks, definitive ear auricle and tongue, palatine shelves, and tuber- culum labii superior, were examined. During the examinations, appropriate planar cuts and dissections were made on the specimens. Typical developmental stages were then photographed, using the large universal photographic stand Multiphot (Nikon, Tokyo). Some of the specimens brought to the Department in the fresh state were photographed intact in color. In selected embryos the whole body was sectioned serially. The sections were stained with hematoxylin and eosin, and photographed at low magnification. A certain number of cleared specimens at various stages were examined for development of the craniofacial skeleton. The coloration methods used were Van Wijhe's methylene blue cartilage staining modified by Noback?) or alizarin red S staining according to Jensh and Brent®). In addition, roentgenograms of a certain number of the fixed specimens at various stages were made with a soft X-ray machine (Softex CSM, Nippon Softex, Tokyo), or a diagnostic X-ray machine (KX0O-1000, Toshiba, Tokyo). Occasion- ally, before roentgenography these specimens were immersed in a 19, aqueous solution of silver nitrate for a period of 2 days to 3 weeks according to O’Rahilly and Meyer®. Specimens with malformations in the oral cavity, face or neck: Careful observations of the malformed region were made for identification of the type of defect, and photographs were taken. Histological examination or dissection was then performed in order to detect internal anomalies. In some cases, other tech- niques such as X-ray examination were also employed. » Streeter, G. L.: Contrib. Embryol., 30: 213, 1942; 31: 29, 1945; 32: 133, 1948; 34: 165, 1951. » O'Rahilly, R.: Developmental Stages in Human Embryos. Part A: Embryos of the first three weeks (stages 1 to 9). Carnegie Inst. Wash., Publ. 631, 1973. ® Noback, G. J.: Anat. Rec. 11: 292, 1916. + Jensh, R. P. and Brent, R. L.: Stain Technol. 41: 179, 1966. » O’'Rahilly, R. and Meyer, D. B.: Am. J. Roentogenol. Radium Ther. Nucl. Med. 76: 455, 1956. Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure FOREWORD ....................ciiiiiiinnnn. PREFACE ...ccvimsininninimins saiasanitsimomais ACKNOWLEDGEMENTS ....................... OUTLINE OF WORK ...................oouun. NORMAL PRENATAL DEVELOPMENT OF ORAL-FACIAL STRUCTURES. ................. EMBRYONIC STAGES (CARNEGIE) 1 Stage 6... 2-3 Stage 79 oon iiinni iin inins nines ina 4-7 Stage 10-11 ............ ii... 8-14 Stage IZ oni mins rnansnnivimninaEn ning sus 15-19 SAGE 18 1 onvn nmiattmme dna womms Hho ie vino 20-29 Stage 14 ...... 30-34 SIZE 15: : casnssmimiantma ss smi Badninsdnigisns 35-42 Stage 16 ............. 43-49 SAGE 17 . svrusenras inimsngsmins imma are ns 50-57 Stage 18 ..... 58-59 Sage 19 cc vvusvrimrsmsmsnr emoms mums amens vas 60-65 Stage 20... 66-70 Sage 21 ..u.urumrmrnsinins rvrararensanenr age 71-75 SABE 22 simran nsan mr aniBinbi ns SRRBINT ATES 76-84 Stage 23 LL FETAL STAGES (CROWN-RUMP LENGTH) 85-99-VT 31to 100mm ................ 100-112 J0L to 200 M001. «ps vswremens srsmemmensnm muss 113-122 201 mm to newborn.......................... SOME ORAL-FACIAL MALFORMATIONS FOUND IN EMBRYOS AND FETUSES. ......... CLEFT LIP 123-129 Unilateral ...... civniusmsenimsarsnsneinsnns 130-131 Bilateral ..coniuninsnnmatbome sbtmmnnibonsomin 132 Median .............. iii 133-135 Cleft Palate .:....osn nvivivsinsnsansasnnsnsns 136-152 Malformations of Branchial Arches and Pinna .... 153-159 Holoprosencephaly ............................ 160-161 Other Malformations .......................... APPENDIX ............... iii Page iii vi vil ix II. Normal Prenatal Development of Oral-facial Structures A. Carnegie Stage 6 Ficure 1.—Blastocyst at Carnegie stage 6 ( x 120). embryonic disc yolk sac amniotic sac DiacraM 1.—Schema of Figure 1. B. Carnegie Stages 7-9 Ficure 2.—Dorsal view of a presomite embryo at Carnegie stage 7 (x 27). Ficure 3.—Dorsal view of a presomite embryo at Carnegie stage 9 (xX 27). embryonic disc primitive knot primitive streak yolk sac Diagram 2.—Schema of Figure 2. yolk sac neural groove neural plate cut edge of amnion primitive knot primitive streak Diagram 3.—Schema of Figure 3. C. Carnegie Stages 10-11 Ficure 4.—Lateral view of a 8 somite-embryo at Carnegie stage 10 ( X 25). Ficure 5.—Lateral view of a 14 somite-embryo at Carnegie stage 11 (x 17). pericardial swelling neural fold branchial arch | brarichial arch If — fused part of neural folds somite connecting stalk Dracram 4.—Schema of Figure 4. anterior neuropore branchial arch | otic placode pericardial swelling somite connecting stalk posterior neuropore Diagram 5.—Schema of Figure 5. Ficure 6.—Face of an embryo at Carnegie stage 11 (x 50). Ficure 7.—Lateral view of the head region of an embryo at Carnegie stage 11 (Xx 63). mandibular process . oropharyngeal membrane (not yet ruptured) pericardial swelling DiacraM 6.—Schema of Figure 6. head stomodeum otic placode branchial arch | and II yolk sac a Diagram 7.—Schema of Figure 7. D. Carnegie Stage 12 Ficure 8.— Lateral view of an embryo at Carnegie stage 12 (x 64). 10 otic pit optic placode branchial arch I, Il and Ill pericardial swelling somite Diagram 8.—Schema of Figure 8. DiacraM 9.—Schema of Figure 9. Ficure 9.—Lateral view of an embryo at Carnegie stage 12 (x 27). 11 Ficure 10.—Face of an embryo at Carnegie stage 12 (xX 96). 12 forebrain branchial arch | Diagram 10.—Schema of Figure 10. anterior neuropore oropharyngeal membrane (in the process of rupturing) pericardial swelling 13 Ficure 11.—Frontal view of the face of an embryo at Carnegie stage 12 ( xX 26). Ficure 12.—Oblique view of the face of the same embryo as shown in Fig. 11 (x 22). 14 maxillary process ruptured oropharyngeal membrane Diagram 11.—Schema of Figure 11. forebrain DiacraM 12.—Schema of Figure 12. branchial arch I, Il and Ill maxillary process branchial arch I, Il and Ill 15 16 Ficure 13.—Sagittal section of the upper half of an embryo at Carnegie stage 12 ( x 34). Ficure 14.—Histological section of the upper half of an embryo at Carnegie stage 12 (H. E. staining) (XxX 35). optic vesicle pharyngeal pouch | branchial arch | branchial arch Il pharyngeal pouch Il cardiac tube notochord Diagram 13.—Schema of Figure 13. optic vesicle brain vesicles QO \ buccal cavity pharynx branchial arch | foregut endocardium DiacraM 14.—Schema of Figure 14. 17 E. Carnegie Stage 13 Ficure 15.—Lateral view of an embryo at Carnegie stage 13 ( x 69). 18 lens placode 2) branchial arch I, II, Ill and IV nasal placode heart arm bud umbilical cord oo A A somite 0 7 leg bud mesonephric prominence Diagram 15.—Schema of Figure 15. 19 20 Ficure 16.—Front view of the face of an embryo at Carnegie stage 13 (x 111). nasal placode maxillary process. branchial arch | or branchial arch Ill Diagram 16.—Schema of Figure 16. 21 22 Ficure 17.—Bottom of the oral cavity of an embryo at Carnegie stage 13 (x 100). pharyngeal pouch | branchial arch | cut edge of aortic arches branchial arch Il pharyngeal pouch II pharyngeal pouch Ill branchial arch II branchial arch IV larynx pharyngeal pouch IV Diagram 17.—Schema of Figure 17. 23 Ficure 18.—Sagittal section of the upper half of an embryo at Carnegie stage 13 (xX 16). Ficure 19.—Histological section of the upper half of an embryo at Carnegie stage 13 (H. E. staining) 24 (x 18). forebrain midbrain . . mesencephalic flexure optic vesicle hypophyseal pouch cardiac tube hindbrain branchial arch I, Il, Ill and IV pharyngeal pouch I, II, lll and IV Diacram 18.—Schema of Figure 18. nasal placode d O TN optic vesicle oral cavity cts branchial arch | NU fourth ventricle - thyroid A \ J esophagus dorsal aorta DiacraM 19.—Schema of Figure 19. 25 F. Carnegie Stage 14 Ficure 20.— Lateral view of an embryo at Carnegie stage 14 (x 65). 26 fourth ventricle branchial arches I, Il and Ill cervical sinus lens pit fore limb nasal placode umbilical cord mesonephric ridge tail hind limb Diagram 20.—Schema of Figure 20. 27 28 Ficure 21.—Lateral view of an embryo in the chorionic sac at Carnegie stage 14 ( x 7.0). Ficure 22.— Lateral view of an embryo at Carnegie stage 14 (x 14). Diagram 21.—Schema of Figure 21. ” DiacraM 22.—Schema of Figure 22. 29 Ficure 23.—Front view of the face of an embryo at Carnegie stage 14 (x 18). nasal placode maxillary process branchial arch |, [1 and Ill DiacraM 23.—Schema of Figure 23. 30 frontal process lens pit maxillary process branchial arch |, Il and Ill cervical sinus Diagram 24.—Schema of Figure 24. Ficure 24.—Oblique view of the face of the same embryo as shown in Figure 23 ( x 16). 31 Ficure 25.—Roof of the oral cavity of an embryo at Carnegie stage 14 ( x 74). nasal placode DiacraM 25.—Schema of Figure 25. frontal process hypophyseal pouch 33 34 Ficure 26.—Anterior part of the bottom of the oral cavity of an embryo at Carnegie stage 14 (Xx 45). Ficure 27.— Posterior part of the bottom of the oral cavity of an embryo at Carnegie stage 14 ( x 55). lateral lingual swelling tuberculum impar haryngeal pouch I, Il and lll praryngeal.p branchial arch I, II, Ill and IV Diagram 26.—Schema of Figure 26. lateral lingual swelling branchial arch |, 11, ll and IV aortic arches tracheal groove nt arytenoid swelling Diagram 27.—Schema of Figure 27. 35 36 Ficure 28.— Lateral view of the central nervous system of an embryo at Carnegie stage 14 (x 5 mesencephalon diencephalon mesencephalic flexure telencephalon metencephalon optic cup J } } trigeminal nerve lens vesicle // fourth ventricle facial nerve auditory vesicle myelencephalon glossopharyngeal nerve c c < LL ——— F———\ © vagus nerve < / accessory nerve < < hypoglossal nerve NE cervical nerve N Dracram 28.—Schema of Figure 28. 37 38 Ficure 29.— Histological section of the upper half of an embryo at Carnegie Low Sas stage 14 (H. E. staining) ( x 45). fourth ventricle pharynx esophagus pericardial cavity liver mesencephalon hypophyseal pouch | aa oral cavity 7, “/ foramen caecum J thyroid DiacraM 29.—Schema of Figure 29. 39 G. Carnegie Stage 15 Ficure 30.—Lateral view of an embryo at Carnegie stage 15 ( x 33). 40 fourth ventricle eye J, 77 branchial arch I, Il and Ill cervical sinus nasal pit umbilical cord fore limb tail mesonephric ridge hind limb Diagram 30.—Schema of Figure 30. ~ Diagram 31.—Schema of Figure 31. Ficure 31.—Lateral view of an embryo at Carnegie stage 15 in the amnion (x 5.0). 41 Ficure 32.—Front view of the face of an embryo at Carnegie stage 15 (xX 17). 42 Ficure 33.—Oblique view of the face of the same embryo as shown in Figure 32 ( x 16). Diagram 33.—Schema of Figure 33. DiacraMm 32.—Schema of Figure 32. nasal pit maxillary process branchial arch |, Il and Ill eye nasal pit maxillary process branchial arch I, Il and Ill cervical sinus 43 44 FicUure 34.—Sagittal section of the upper half of an embryo at Carnegie stage 15 ( x 28). neuromeric region metencephalon = myelencephalon mesencephalic flexure, — SON sulcus limitans LA BN mesencephalon oral cavity hypophyseal pouch \ | pr— “NU I cervical flexure Ye | diencephalon - tongue / atrium lumen of the optic stalk (J | telencephalon ventricle Diagram 34.—Schema of Figure 34. 45 H. Carnegie Stage 16 Ficure 35.—Lateral view of an embryo at Carnegie stage 16 ( xX 32). 46 branchial arch | and Il J with auricular hillocks eye with retinal pigment cervical sinus nasolacrimal groove fore limb nasal pi pit hand plate umbilical cord tail hind limb DiacraMm 35.—Schema of Figure 35. Diagram 36.—Schema of Figure 36. Ficure 36.—Lateral view of an embryo at Carnegie stage 16 in the amnion (x 5.0). 47 Ficure 37.— Front view of the face of an embryo Carnegie stage 16 (x 17). 48 at Ficure 38.—Oblique view of the face of an embryo at Carnegie stage 16 ( x 20). lateral nasal process medial nasal process Diagram 37.—Schema of Figure 37. nasal pit maxillary process branchial arch I and II nasolacrimal groove eye lateral nasal process nasal pit NLA) medial nasal process maxillary process branchial arch | and II with auricular hillocks Diagram 38.—Schema of Figure 38. 49 50 FIGURE 39.—Roof of the oral cavity of an embryo at Carnegie stage 16 ( x 72). lateral nasal process hypophyseal pouch Diagram 39.—Schema of Figure 39. ) nasal pit 52 FicUure 41.— Posterior part of the bottom of the oral cavity of an embryo at Carnegie stage 16 (x 46). — lateral lingual swelling tuberculum impar foramen caecum branchial arch II pharyngeal pouch | and II iolotti . , epiglottis arytenoid swelling DiacraM 40.—Schema of Figure 40. lateral lingual swelling tuberculum impar pharyngeal pouch land II branchial arch Il epiglottis arytenoid swelling Diagram 41.—Schema of Figure 41. 53 54 FicURE 42.— Lateral view of the brain of an embryo at Carnegie stage 16 ( x 33). mesencephalic flexure mesencephalon diencephalon oculomotor nerve telencephalon metencephalon eye trigeminal nerve pontine flexure facial nerve glossopharyngeal nerve superior ganglion of vagus nerve inferior ganglion of vagus nerve hypoglossal nerve myelencephalon cervical flexure cervical nerve Diagram 42.—Schema of Figure 42. 33 I. Carnegie Stage 17 Ficure 43.—Lateral view of an embryo at Carnegie stage 17 in the chorionic sac ( x 13). 56 chorion frondosum eye with retinal pigment branchial arch I and II with auricular hillocks } } chorionic cavity hand plate yolk sac amnion hind limb chorion laeve Diagram 43.—Schema of Figure 43. 5 Ho Figure 44.—Front view of the face of Diagram 44.—Schema of Figure 44. an embryo at Carnegie stage 17 ( x 9.0). 57 Figure 45.—Front view of the face of an embryo at Carnegie stage 17 (x 6.4). Ficure 46.—Oblique view of the face of the - same embryo as shown in Figure 45 (x 7.3). 58 lateral nasal process nasal pit » maxillary process >> ND — medial nasal process \ branchial arch | -auricular hillocks Diagram 45.—Schema of Figure 45. lateral nasal process nasal pit nasolacrimal groove medial nasal process maxillary process auricular hillocks DiacraM 46.—Schema of Figure 46. 59 60 FiGure 47.—Roof of the oral cavity of an embryo at Carnegie stage 17 (x 13). Ficure 48.—Bottom of the oral cavity of an embryo at Carnegie stage 17 ( x 20). lateral nasal process nasal pit maxillary process medial nasal process hypophyseal pouch Diagram 47.—Schema of Figure 47. lower lip tongue ’ branchial arch | sulcus terminalis epiglottis tracheal groove arytenoid swelling Diagram 48.—Schema of Figure 48. 61 62 Ficure 49.— Histological section of the upper half of an embryo at Carnegie stage 17 (H. E. staining) (x 27). myelencephalon metencephalon oral cavity — mesencephalon pharynx hypophyseal pouch tongue diencephalon esophagus telencephalon spinal cord ventricle of heart liver O DiacraM 49.—Schema of Figure 49. 63 J. Carnegie Stage 18 Ficure 50.—Lateral view of an embryo at Carnegie stage 18 (x 25). 64 eye with retinal pigment _ auricular hillocks eyelid hand plate with digital rays nasolacrimal groove umbilical cord - foot plate with digital rays Diagram 50.—Schema of Figure 50. Diagram 51.—Schema of Figure 51. Ficure 51.—Lateral view of an embryo at Carnegie stage 18 (x 5.0). 65 Ficure 52.—Front view of the face of an embryo at Carnegie stage 18 (x 7.4). Figure 53.—Oblique view of the face of an embryo at Carnegie stage 18 (xX 7.6). 66 eye with retinal pigment nasolacrimal groove nasal pit mandible Diacram 52.—Schema of Figure 52. _eye with retinal pigment (Note that the medial inferior portion is not pigmented.) lens nasal pit sal p ~ - maxillary process nasolacrimal groove — auricular hillocks Diagram 53.—Schema of Figure 53. 67 68 Ficure 54.—Roof of the oral cavity of an embryo at Carnegie stage 18 ( xX 53). primary palate primitive posterior naris palatal process Diagram 54.—Schema of Figure 54. maxillary process nasal septum rudiment of hypophyseal pouch 69 70 FiGure 55.—Anterior part of the bottom of the oral cavity of an embryo at Carnegie stage 18 ( xX 35). Ficure 56.—Posterior part of the bottom of the cral cavity of the {xX 33). same embryo as shown in Figure 55 lower lip body of the tongue tuberculum impar sulcus terminalis branchial arch Il root of the tongue iglotti arytenoid swelling epiglottis Diagram 55.—Schema of Figure 55. body of the tongue tuberculum impar sulcus terminalis epiglottis arytenoid swelling Diagram 56.—Schema of Figure 56. 71 72 Ficure 57.—Histological section of the upper half of an embryo at Carnegie stage 18 (H. E. staining) (x 32). fourth ventricle mesencephalon lip esophagus Diacram 57.—Schema of Figure 57. 73 K. Carnegie Stage 19 Ficure 58.— Lateral view of an embryo at Carnegie stage 19 (x 13). 74 external auditory meatus eyelid hand with digital indentation ] nipple foot with toe rays DiacraM 58.—Schema of Figure 58. 75 76 Ficure 59.—Front view of the face of an embryo at Carnegie stage 19 ( xX 38). nasal pit Diagram 59.—Schema of Figure 59. eye 77 L. Carnegie Stage 20 Ficure 60.—Lateral view of an embryo at Carnegie stage 20 ( x 14). 78 scalp vascular plexus umbilical cord foot with digital indentation Diagram 60.—Schema of Figure 60. pinna 79 80 Ficure 61.- Front view of the face of an embryo at Carnegie stage 20 ( xX 24). pinna (07 Ly Diagram 61.—Schema of Figure 61. eyelid 81 82 Ficure 62.—Roof of the oral cavity of an embryo at Carnegie stage 20 ( x 74). upper lip primary palate palatal process Diagram 62.—Schema of Figure 62. vestibule nasal septum rudiment of hypophyseal pouch 83 84 FiGURE 63.— Anterior part of the bottom of the oral cavity of an embryo at Carnegie stage 20 (x 35). Ficure 64.— Posterior part of the bottom of the oral cavity of the same embryo as shown in Figure 63 (x 35). lower lip vestibule body of the tongue - Diagram 63.—Schema of Figure 63. root of the tongue tracheal groove Diagram 64.—Schema of Figure 64. 85 Ficure 65. Histological section of the upper half of an embryo at Carnegie stage 20 (H. E. staining) (x 29). 86 midbrain cerebellum - lateral ventricle fourth ventricle choroid plexus hypophysis third ventricle tongue nasal cavity CJ palatal process epiglottis Sd = - Lo ed - trachea —- | J [_ DiacraM 65.- Schema of Figure 65. 87 M. Carnegie Stage 21 Ficure 66.— Lateral view of an embryo at Carnegie stage 21 (x 10). 88 scalp vascular plexus umbilical cord Diagram 66.—Schema of Figure 66. pinna tail 89 90 Ficure 67.—Oblique view of the face of an embryo at Carnegie stage 21 (x 24). nasal pit (obliterated) Diagram 67.—Schema of Figure 67. pinna 91 92 Ficure 68.— Lateral view of the brain of an embryo at Carnegie stage 21 (x 11). Ficure 69.—Median surface of the left half of the same brain as shown in Figure 68 (x 11). mesencephalon cerebral hemisphere cerebellum mE trigeminal ganglion diencephalon — ~~ eye Sh vagus nerve 2 ") A spinal cord Diagram 68.— Schema of Figure 68. mesencephalon thalamus cerebral hemisphere cerebellum hypothalamus foramen of Monro rhomboid fossa olfactory bulb optic chiasma DiacraM 69.— Schema of Figure 69. 93 94 Ficure 70.— Histological section of the upper half of an embryo at Carnegie stage 21 (H. E. staining) ( xX 26). cerebellum choroid plexus of the lateral ventricle fourth ventricle tongue epiglottis palatal process esophagus tooth bud trachea Meckel's cartilage Diagram 70.—Schema of Figure 70. 95 N. Carnegie Stage 22 Ficure 71.—Lateral view of an embryo at Carnegie stage 22 (x 11). 96 scalp vascular plexus pinna elbow umbilical cord knee TT — regressing tail Diacram 71.—Schema of Figure 71. 97 98 Ficure 72.—Front view of the face of an embryo at Carnegie stage 22 (xX 5.6). Ficure 73.—Oblique view of the face of the same embryo as shown in Figure 72 ( X 6.4). scalp vascular plexus cornea nostril pinna Diagram 72.—Schema of Figure 72. scalp vascular plexus pinna Diagram 73.—Schema of Figure 73. 99 7 i Ficure 74.—Roof of the oral cavity of an embryo at Carnegie stage 22 (x 12). Ficure 75.—Bottom of the oral cavity of an embryo at Carnegie stage 22 (x 17). 100 ~ \v upper lip vestibule posterior nares ~ - rudiment of palatal process hypophyseal pouch Diagram 74.—Schema of Figure 74. lower lip gum body of the tongue fungiform papillae vallate papillae root of the tongue epiglottis arytenoid swelling Diacram 75.—Schema of Figure 75. 101 O. Carnegie Stage 23 Ficure 76.— Lateral view of an embryo at Carnegie stage 23 (x 10). 102 scalp vascular plexus ( —— pinna eyelids in the process of fusion tail disappeared Diagram 76.—Schema of Figure 76. 103 Ficure 77. Lateral view of an embryo at Carnegie stage 23 surrounded by the amnion and connected to the chorionic sac with umbilical cord (x 1.0). Ficure 78. Lateral view of an embryo at Carnegic stage 23 (x 4.0). 104 amnion yolk sac chorionic sac Diagram 77.—Schema of Figure 77. Diagram 78.—Schema of Figure 78. 105 Ficure 79.— Oblique view of the face of an embryo at Carnegie stage 23 (x 4.1). Ficure 80.—Close-up of the optic region of the same embryo as shown in Figure 79 ( x 8.8). 106 nostril pinna Diagram 79.—Schema of Figure 79. cornea em _— sclera Diagram 80.—Schema of Figure 80. 107 : Ficure 81.—Roof of the oral cavity of an embryo at Carnegie stage 23 ( x 19). Ficure 82.—Bottom of the oral cavity of an embryo at Carnegie stage 23 ( x 15). 108 ————— upper lip primary palate incisive canal palatal process nasopharynx Diagram 81.—Schema of Figure 81. lower lip median sulcus gum tongue with villous surface lingual tonsil epiglottis Diagram 82.—Schema of Figure 82. 109 Ficure 83.—Median section of an embryo at Carnegie stage 23. Nasal septum is removed. ( x 25). 110 superior nasal concha DU middle nasal concha - inferior nasal concha gum tongue upper lip epiglottis lower lip hyoid cartilage — Diacram 83.—Schema of Figure 83. 111 Ficure 84.— Histological section of an embryo at Carncgic stage 23 (H. E. staining) ( x 10). 112 hypophysis alatal process p p nasal concha epiglottis _ body of the tongue root of the tongue 0 > tooth bud esophagus — Q A lip trachea = QO CD SO Meckel's cartilage hyoid cartilage \ hy, \ heart lung 3S liver intestine © 40 Diagram 84.—Schema of Figure 84. 113 P. Fetal stage from 31 to 100 mm in crown-rump length Ficure 85.— Lateral view of a fetus of 65 mm in crown-rump length together with the amnion and the yolk sac (arrow) (x 5.8). 114 k sac - . yol amnion umbilical cord Diagram 85.—Schema of Figure 85. Ficure 86.— Lateral view of a fetus of 35 DiacraMm 86.— Schema of Figure 86. mm in crown-rump length (x 2.0). 115 Ficure 87.— Front view of the face of a fetus of 52 mm in crown-rump length (x 2.0). Figure 88.— Lateral view of the face of the same fetus as shown in Figure 87 (x 2.8). 116 fused eyelid — nostril Diacram 87.—Schema of Figure 87. fused eyelid SN Q) pinna Diagram 88.—Schema of Figure 88. 117 Ficure 89. Close-up of the lip of the same fetus as shown in Figure 87 ( x 9.0). Ficure 90.—Roof of the oral cavity of a fetus of 33 mm in crown-rump length ( x 16). 118 nostril O = Diagram 89. Schema of Figure 89. upper lip vestibule plicae palatinae transversae palatal / soft palate (not yet fused) Diagram 90.-—Schema of Figure 90. 119 Ficure 92.—Roof of the oral cavity of a fetus of 92 mm in crown-rump length ( x 4.3). 120 plicae palatinae transversae uvula (bifid) VV Diagram 91.—Schema of Figure 91. plicae palatinae transversae em}. uvula Diagram 92.—Schema of Figure 92. 121 Ficure 93.— Bottom of the oral cavity of a fetus of 47 mm in crown-rump length (x 15). Ficure 94.—Bottom of the oral cavity of the same fetus as shown in Figure 93 stained with methylene blue ( x 11). 122 lower lip Ny eed) lingual tonsil epiglottis arytenoid swelling DiacraM 93.— Schema of Figure 93. fungiform papilla gum vallate papilla : pap lingual tonsil Diagram 94.— Schema of Figure 94. 123 Figure 95.—Sagittal section of the head of a fetus of 31 mm in crown-rump length (x 20). 124 superior concha middle concha inferior concha opening of auditory tube palate tongue epiglottis hyoid cartilage Meckel’s cartilage Diagram 95.— Schema of Figure 95. 125 Ficure 96-FT.— Front view of the skull of a fetus of 52 mm in crown-rump length (cleared specimen i stained with alizarin red S showing calcified bones Js: . (x 3.6). Ficure 96-LT.— Lateral view of the same specimen as shown in Figure 96-FT (x 3.7). { Figure 96-VT.— Vertical view of the same specimen as shown in Figure 96-FT ( x 3.6). 126 frontal bone / mandible — Diagram 96-FT.— Schema of Figure 96-FT. frontal bone NE A mandible MN ’ — Diagram 96-VT.—Schema of Figure 96-VT. frontal bone \ / malar bone * / N / maxilla / interparietal bone nandible \ | supraoccipital bone Diagram 96-LT.—Schema of Figure 96-1T. 127 Figure 97-FT.—Front view of the skull of a fetus of 72 mm in crown-rump length (cleared specimen stained with alizarin redS) (x 1.6). = Ficure 98-PA.—Posterior-anterior roentgenogram ¥ ve of a fetus of 73 mm in crown-rump length (stained with silver nitrate) (x 1.0). 128 I» \ medial pterygoid center | X * \ frontal bone perpendicular plate of ethmoid bone nasal bone maxilla malar bone mandible C/ Diagram 97-FT.—Schema of Figure 97-FT. frontal bone maxi a vomer 3 3 | 4 / zygomatic bone er XN A malar bone mandible 4% Diagram 98-PA.—Schema of Figure 98-PA. 129 Ficure 97-LT.—Lateral view of the same specimen as shown in Figure 97-FT (x 1.1). Ficure 98-DS.——Dextro-sinistral rocntgenogram of the same specimen as shown in Figure 98-PA (x 1.0). 130 frontal bone parietal bone nasal bone squamous part maxilla of temporal bone interparietal bone malar bone zygomatic arch supraoccipital bone mandible occipital arch tympanic ring Diagram 97-LT.—Schema of Figure 97-LT. frontal bone maxilla interparietal bone malar bone supraoccipital bone _ mandible occipital arch Diagram 98-DS.— Schema of Figure 98-DS. 131 Ficure 98-SP.—Submento-parictal roentgenogram of the same specimen as shown in Figure 98-PA (x 1.0). Ficure 97-VT.—Vertical view of the same specimen as shown in Figure 97-FT (x 1.5). a 132 Ficure 99-VT.—Base of the skull of a fetus of 72 mm in crown-rump length (cleared specimen stained with methyl- ene blue showing cartilaginous skeleton (x 1.2). i” mandible tympanic ring zygomatic arch ~ ™ basioccipital bone CQ ™ foramen magnum exooccipital bone " \ occipital bone Diacram 97-VT.—Schema of Figure 97-VT. zygomatic arch —_ mandible \ . exooccipital bone Diagram 98-SP.—Schema of Figure 98-SP. rd , - 50, N Meckel's cartilage / hyoid cartilage dorsal sellae Diagram 99-VT.—Schema of Figure 99-VT. 133 Q. Fetal stage from 101 to 200 mm in crown-rump length Ficure 100.—Lateral view of a fetus of 120 mm in crown-rump length ( x 1.6). 134 fused eyelids pinna Diagram 100.—Schema of Figure 100. 135 136 Ficure 101.—Oblique view of the face of a fetus of 145 mm in crown-rump length (x 1.4). a Ficure 102.—Oblique view of the face of a fetus of 190 mm in crown-rump length (x 1.1). scalp hairs — eyebrow tuberculum labii superioris lanugo hairs Diagram 101.— Schema of Figure 101. scalp hairs eyebrow a= Diagram 102.-—Schema of Figure 102. 137 Ficure 103.—Front view of the mouth of a fetus of 123 mm in crown-rump length (x 5.5). 138 frenulum of upper lip \ fo / gum cuspid 7 apex of tongue Diagram 103.—Schema of Figure 103. 139 “ ay Ficure 104. Roof of the oral cavity of a fetus of 144 mm in crown-rump length ( x 140 upper lip vestibule palatal papilla segmented gum transverse palatine ridges gingival groove palatal raphe dental groove Diagram 104.—Schema of Figure 104. 141 Ficure 105.— Anterior part of the bottom of the oral cavity of a fetus of 140 mm in crown-rump length ( x 1.6). Figure 106.—Posterior part of the bottom of the oral cavity of the same fetus as shown in Figure 105 ( xX 1.6). Figure 107.—Close-up of the tongue of the same specimen as 142 shown in Figure 106 (x 4.4). lower lip vestibule tongue with papillae Diacram 105.—Schema of Figure 105. lingual tonsil epiglottis Diagram 106.—Schema of Figure 106. fungiform papilla O CP O oO O— Le papillae Ne . lingual tonsil Diagram 107.—Schema of Figure 107. 143 Ficure 108.—Sagittal section of the face of a fetus of 175 mm in crown-rump length ( x 4.0). Ficure 109. Frontal section of the face of a fetus of 192 mm in crown-rump length (x 1.4). 144 tooth primordium — upper lip tongue with papillae — lower lip with villous surface salivary gland tooth primordium — hair follicles sublingual salivary gland —— bone of mandible ___ Diagram 108.—Schema of Figure 108. crista galli _ —— eye _ _ eri nasal septum 9 © inferior nasal concha tooth primordium gum tongue —— — lower gum Diagram 109.—Schema of Figure 109. 145 146 Figure 110. Lateral view of the brain of a fetus of 170 mm in crown-rump length ( x 2.9). central fissure parietal lobe occipital lobe insula frontal lobe temporal lobe cerebellum medulla oblongata N Diagram 110.—Schema of Figure 110. 147 Figure 111-FT.—Front view of the skull of a fetus of 116 mm in crown-rump length (cleared specimen stained with alizarin red S showing calcified bones) (x 1.0). Figure 112-PA.—Posterio-anterior roentgenogram of the skull of a fetus of 116 mm in crown-rump length 148 (stained with silver nitrate) (x 1.0). frontal bone parietal bone nasal bone 4 temporal bone zygomatic bone maxilla mandible perpendicular plate of ethmoid bone Diagram 111-T'T.—Schema of Fig. 111-FT. frontal bone _— parietal bone lacrimal bone vomer ~~ ——— mandible Diagram 112-PA.—Schema of Figure 112—-PA. 149 Figure 111-LT.— Lateral view of the same specimen as shown in Figure 111-FT (x 1.1). Ficure 112-DS.—Dextro-sinistral roentgenogram of the same specimen as shown in Figure 112-PA ( x 1.0). 150 parietal bone frontal bone temporal bone nasal bone maxilla zygomatic arch fy APRN —X vy A prance bone mandible tympanic ring basioccipital bone Diagram 111-LT.—Schema of Figure 111-LT. parietal bone frontal bone temporal bone malar bone 4 i interparietal oo \ 7 bone nasal bone DZ oy supraoccipital bone maxilla NY W 5 X zygomatic arch Fr I" { “35 occipital arch - ? fT TY mandible tympanic ring basioccipital bone Diagram 112-DS.— Schema of Figure 112-DS. 151 Ficure 111-VT.—Base of the skull of the specimen as shown in Figure 111-FT (mandible is removed) (x 1.3). Figure 112-SP.—Submento-parietal roentgenogram of the same specimen as shown in Figure 112-PA (x 1.0). 152 maxilla palatine process of maxilla ~ zygomatic arch palatine process of ethmoid bone foramen magnum / / C : ~N Ir tympanic ring exooccipital bone supraoccipital bone interparietal bone Diagram 111-VT.—Schema of Figure 111-VT. maxilla mandible basioccipital bone zygomatic arch foramen magnum exooccipital bone parietal bone il er SE supraoccipital bone interparietal bone Diagram 112-SP.— Schema of Figure 112-SP. 153 R. From fetal stage at 201 mm in crown-rump length to newborn Figure 113.— Front view of a stillborn fetus of 288 mm in crown-rump length ( x 0.5). 154 well rounded contour of the skin > 74 Diagram 113.—-Schema of Figure 113. 155 Ficure 114. Front view of the face of the same fetus with Figure 113 (x 0.8). Ficure 115.—Lateral view of the face of a neonatally dead infant of 325 mm in crown-rump length ( x 0.8). 156 157 Ficure 116.—Roof of the oral cavity of a stillborn fetus of 340 mm in crown-rump length (x 1.6). Ficure 117.—Front view of the oral cavity of a stillborn fetus of 380 mm in crown-rump length (x 2.2). 158 ———— villous surface of the lip frenulum villous surface of the gum Diagram 116.—Schema of Figure 116. upper lip with villous surface frenulum upper gum with villous surface lower gum with villous surface lower lip with villous surface Diagram 117.—Schema of Figure 117. 159 Ficure 118.—Sagittal section of the head of a stillborn fetus of 264 mm in crown-rump length. 160 middle nasal concha superior nasal concha inferior nasal concha sella turcica hard palate auditory tube lips soft palate primoridal tooth epiglottis tongue Diagram 118.—Schema of Figure 118. 161 1G .— I cw e Dr pi 1 rm ie m n Cr n- rt} 29 cng ( X 2.2) . I 1 9 1 of t brain of a st DO etus of 240 mm ir own-rump & he a It fet f RE Lateral v n neth 162 parietal lobe central fissure frontal lobe lateral fissure i occipital lobe insula temporal lobe cerebellum medulla oblongata Diagram 119.—Schema of Figure 119. 163 Figure 120-PA.—Posterio-anterior roentgenogram of the skull of a stillborn fetus of 210 mm in crown- rump length (x 1.0). Ficure 120-SPA.—Posterio-anterior roentgeno- gram of the same specimen as shown in Figure 120—PA after staining with silver nitrate ( X 1.0) 164 frontal bone parietal bone vomer temporal bone nasal bone zygomatic bone J oT maxilla mandible - Diagram 120-PA.—Schema of Figure 120-PA. parietal bone frontal bone temporal bone _. nasal bone vomer . ie" zygomatic arch maxilla — Tt — malar bone —— ~ mandible DiacraMm 120-SPA.—Schema of Figure 120-SPA. 165 Ficure 120-SDS.—Dextro-sinistral roentgenogram of the specimen as shown in Figure 120-SPA ( x 1.0) Right half is removed. 166 anterior clinoid process of sphenoid bone frontal bone lacrimal bone parietal bone nasal bone temporal wing interparietal portion of sphenoid bone of occipital bone maxilla od supraoccipital portion zygomatic bone of occipital bone zygomatic arch 0] occipital arch mandible tympanic ring squamous portion of temporal bone Diagram 120-SDS.—Schema of Figure 120-SDS. 167 Ficure 120-SP.—Submento-parictal ~~ roentgeno- gram of the same specimen as shown in Figure 120-PA (x 1.0). Ficure 120-SSP.-——Submento-parietal roentgeno- gram of the same specimen as shown in Figure 168 120-SPA (x 1.0). mandible palatine bone \ Q superimposed ’ 5 petrous pyramid - \ of temporal bone x tympanic ring mastoid cells basioccipital bone exoccipital bone foramen magnum “temporal bone parietal bone ET occipital bone — Cp Diagram 120-SP.—Schema of Figure 120-SP. perpendicular plate of ethmoid bone palatine bone mandible zygomatic arch mastoid cells basioccipital bone zympanic ring foramen magnum exoccipital bone temporal bone parietal bone Ee TIE snes occipital bone Diagram 120-SSP.—Schema of Figure 120-SSP. 169 am Figure 121-PA.—Posterio-anterior roentgenogram of the skull of a still- born fetus of 325 mm in crown-rump length (x 1.0). 170 parietal bone temporal bone frontal bone } lacrimal bone vomer nasal bone zygomatic bone maxilla — — ~ sphenoid bone mandible inferior nasal concha partially mineralized deciduous tooth and dental crypt Diagram 121-PA.— Schema of Figure 121-PA. 171 172 Hy il ih Hina (1141 DER EE HA | ith b Hi RAR ERR i! i 1 HH HEHE LH Ficure 121-DS.—Dextro-sinistral roentgenogram of the same specimen as shown in Figure 121-PA (x 1.0). frontal bone anterior clinoid process of sphenoid bone nasal bone _ hypophyseal fossa _ external auditory meatus maxilla molar tooth — Rs al Zz » incisor tooth occipital bone ns rd } ~ mandible Diagram 121-DS.— Schema of Figure 121-DS. 173 Ficure 121-SP.—Submento-parietal roentgenogram of the same specimen as shown in Figure 121-PA ( x 1.0). 174 perpendicular plate of ethmoid bone palatine bone orbit — pterygoid process “zygomatic arch temporal wing of sphenoid bone NN ~ temporal bone Pg A parietal bone ~ mastoid cells / / foramen magnum superimposed petrous pyramid of temporal bone occipital bone Diagram 121-SP.—Schema of Figure 121-SP. 175 176 Ficure 122-FT.—Front view of the skull of a newborn ( x 0.6). Figure 122-LT.— Lateral view of the same speci- men as shown in Figure 122-FT (x 0.6). Figure 122-VT.—Base of the skull of the same specimen as shown in Figure 122-FT (x 0.6). frontal bone parietal bone supraorbital foramen temporal bone nasal bone infraorbital foramen maxilla zygomatic bone — zygomatic arch mandible mental foramen Diagram 122-FT.—Schema of Figure 122-FT. anterior fontanelle frontal tuber parietal tuber sphenoidal fontanelle posterior fontanelle greater wing of sphenoid bone —— occipital squama —mastoid fontanelle squamous portion of temporal bone tympanic ring \ lateral portion of occipital bone ~ mastoid portion of temporal bone Diagram 122-LT.—Schema of Figure 122-LT. mandible palatine process of maxilla _ zygomatic arch ra zygomatic bone basilar portion of occipital bone — lateral portion of occipital bone - foramen magnum occipital condyle mastoid fontanelle —— supraoccipital portion of occipital squama interparietal portion of occipital squama Diagram 122-VT.—Schema of Figure 122-VT. 177 III. Some Orofacial Malformations Found in Embryos and Fetuses 178 A. Cleft lip 1. Unilateral cleft lip Figure 123.—Front view of the face of an embryo with possibly right sided cleft lip (Carnegie stage 18). Ficure 124.— Front view of the face of an embryo with right sided cleft lip (Carnegie stage 18). 179 Ficure 125. Front view of the face of an embryo with right sided cleft lip (Carnegie stage 19). Ficure 126.— Front view of the face of an embryo with left sided cleft lip (Carnegie stage 20). 180 Figure 127.—Front view of the face of an embryo with left sided cleft lip (Carnegie stage 22). 181 Figure 128.— Front view of the face of a fetus with left sided cleft lip (112 mm in crown-rump length). Ficure 129.—Front view of the face of a fetus with right sided cleft lip (162 mm in crown-rump length). 182 2. Bilateral cleft lip Ficure 130.—Front view of the face of an embryo with bilateral cleft lip (Carnegie stage 21). Ficure 131.—Front view of the face of a stillborn fetus with bilateral cleft lip (203 mm in crown-rump length). 183 3. Median cleft lip Ficure 132. Front view of the face of an embryo with median cleft lip combined with holoprosen- cephaly (Carnegie stage 18). 184 B. Cleft Palate Ficure 133.—Roof of the oral cavity of a fetus with left complete cleft of the primary palate (35 min in crown-rump length). 185 Ficure 134.—Roof of the oral cavity of a stillborn fetus with occult cleft of the secondary palate (200 mm in crown-rump length). Ficure 135.— Roof of the oral cavity of a stillborn fetus with incomplete cleft of the secondary palate (225 mm in crown-rump length). 186 C. Malformations of branchial arches and pinna Ficure 136.— Lateral view of an embryo with hypoplasia of branchial arch I (Carnegie stage 16). Ficure 137.—Front view of the same embryo as shown in Figure 136. 187 Ficure 138.— Lateral view of an embryo with small left branchial arch IT (Carnegie stage 14). Figure 139.—Right side of the same embryo as shown in Figure 138 showing the similar anomaly. 188 Ficure 140. Lateral view of an embryo with hypoplastic branchial arch II (Carnegie stage 16). Figure 141. arch II. Lateral view of an embryo with hypoplastic branchial 189 Figure 142.—Lateral view of an embryo with abnormally wide right pharyngeal groove II combined with holoprosencephaly (Carnegie stage 13). 190 Ficure 143.— Lateral view of an embryo with deformed branchial arches IIT and IV (Carnegie stage 14). Ficure 144.—Right side of the same embryo as shown in Figure 143 showing the similar anomaly. 191 Figure 145.— Right side of an embryo with low-set ear (Carnegie stage 19). 192 Ficure 146. Left side showing normal location of ear of the same embryo as shown in Figure 145. & Ficure 147.— Lateral view of an embryo showing a small accessory tubercle (arrow) located between branchial arches I and IT (Combined malformation: pre- axial polydactyly of the right hand) (Carnegie stage 18). ha Fu Ficure 148. Lateral view of an embryo showing fusion of second and fourth auricular hillocks (Carnegie stage 18). 193 Ficure 149.—Lateral view of an embryo showing a small tubercle on the pinna (arrow) (Carnegie stage 21). Figure 150.— Lateral view of an embryo showing two small tubercles on the pinna (arrow) (Carnegie stage 21). 194 f Figure 151.—Lateral view of an embryo showing seriously malformed pinna (Carnegie stage 22). Ficure 152.—Lateral view of a stillborn fetus showing almost definite shape of malformed pinna (215 mm in crown-rump length). 195 D. Holoprosencephaly Ficure 153.—Face of an embryo with holo- prosencephaly showing absent nasal plac- odes (Carnegie stage 14). \ Ficure 154.—Face of an embryo with holopros- encephaly showing reduced nasal region (Car- 196 negic stage 14 . Ficure 155.— Face of an embryo with holoprosencephaly showing cyclopic eyes and proboscis (Carnegie stage 16). 197 198 Ficure 156. Face of a holoprosencepha- lic embryo showing almost fused eyes of both sides and proboscis (Carnegie stage 18). Figure 157.—Face of a holoprosencephalic embryo showing approached eyes of both sides and absent nasal processes (Carnegie stage 18). Ficure 158. embryo showing approached eyes of both sides, pro- Face of a holoprosencephalic dead boscis and absent other nasal part (Carnegie stage 19). Ficure 159.—Front view of a holoprosencephalic stillborn fetus showing definite abnormal facial appear- ance (200 mm in crown-rump length). 199 E. Other malformations Ficure 160.—Front view of a stillborn fetus with multiple facial malformations (cyclopia, low- set ears, microstomia) (265 mm in crown-rump length). 200 Ficure 161.—Lateral view of the head of a fetus with hypertrichosis (178 mm in crown-rump length). 201 Selected References on Embryogenesis and Teratogenesis of Human Oral-Facial Structures A. NORMAL DEVELOPMENT 1. Books and Reviews* Bevelander, G. (1967), Atlas of Oral Histology and Embryology. Lea and Febiger, Philadelphia. Graber, T. M. (1966), Craniofacial and dentitional development. In: F. Falkner (ed.), Human Devel- opment, p. 510. W. B. Saunders, Philadelphia and London. Kraus, B. S., Kitamura, H. and Latham, R. A. (1966), Atlas of Developmental Anatomy of the Face. Harper & Row, New York and London. Mugnier, A. (1964), Embryologie et Developpement Bucco-Facial. Masson et Cie & Julien Prelat, Paris. Noyes, F. B. (1960), Oral Histology and Embry- ology: With Laboratory Directions. Lea and Febiger, Philadelphia. Permar, D. (1963), A Manual of Oral Embryology and Miscroscopic Anatomy. 3rd ed., Lea and Febiger, Philadelphia. Peter, K. (1913), Atlas der Entwicklung der Nase und des Gaumens beim Menschen. Gustav Fischer, Jena. Remnick, H. (1970), Embryology of the Face and Oral Cavity. Fairleigh Dickinson University Press. Rutherford, Madison and Teaneck. Scott, J. H. (1967) Dento-facial Development and Growth. Press, Oxford. Edinburgh, New York-Toronto-Sydney-Paris- Pergamon London- Braunschweig. Sicher, H. and Bhaskar, S. N. (ed.) (1972), Orban’s Oral Histology and Embryology. The C. V. Mosby, St. Louis. * Publications dealing with human embryology in general are excluded. 202 Sperber, G. H. (1973), Craniofacial Embryology. John Wright & Sons Ltd., Bristol. Theiler, K. (1963), Entwicklung und normale Réntgenanatomie des Schidels. I. Embryonale und postnatale Entwicklung des Schidels. In: Olsson, O., Strnad, F., Vieten, H. und Zuppinger, A. (ed.), Handbuch des Medizinischen Radiologie. Bd. VII/1, p. 22. Springer-Verlag, Berlin. Wetzel, G. (1938), Verdauungsapparat (Apparatus digestorius). Die Mundhohle des Kindes. In: Peter, K., Wetzel, G. and Heiderich, F. (ed.), Handbuch der Anatomie des Kindes, Bd. 1. p 629. Verlag von J. F. Bergmann, Miinchen. 2. Original Articles Andersen, H. and Matthiessen, M. E. (1967), Histo- chemistry of the early development of the human central face and nasal cavity with special refer- ence to the movements and fusion of the palatine processes. Acta Anat. (Basel) 68, 473. Arey, L. B. (1947), On the development, mor- phology and interpretation of a system of crypt- analogues in the pharyngeal tonsil. Am J Anat, 80, 203. Baumgartner, E. A. (1917), The development of the serous glands (von Ebner’s) of the vallate papillae in man. Am J Anat, 22, 365. Burdi, A. R. and Faist, K, (1967). Morphogenesis of the palate in normal human embryos with special emphasis on the mechanisms involved. Am J Anat, 120, 149. Burdi, A. R. and Silvey, R. G. (1969), Sexual differ- ences in closure of the human palatal shelves. Cleft Palate J, 6, 1. Chase, S. W. (1942), The early development of the human premaxilla. |] Am Dent Assoc, 29, 1991. Dankmeijer, J. (1968), Some remarks on the devel- opment and anatomy of the septum nasi. Intern. Rhinology, 6, 27. Deggeler, C. (1942), Beitrag zur Kenntnis der Architektur des fetalen Schiadels. Z Anat Entwick- lungsgesch, 111, 470. Dixon, A. D. (1958), The development of the jaw. Dent Pract Dent Rec, 9, 10. Dzillas, P. (1954), Zur Entwicklung des menschli- chen Schideldaches. Anat Anz, 100, 236. Fudii, 1. (1939), Embryologische Studien iiber die Plicae palatinae transversae bei den Japanern. Acta Anat Nippon, 13, 45. (in Japanese with German abstract) Fulton, J. T. (1957), Closure of the human palate in embryo. Am J Obst Gynec, 74, 179. Furstman, L. (1963), The early development of the human temporomandibular joint. Am J Orthod, 49, 672. Garn, S. M. et al. (1970), Prenatal dental develop- ment as a reference standard for embryologic status. | Dent Res, 49, 894. Hill, A. F. (1939). Fetal age assessment by centers of ossification. Am | Phys Anthropol, 24, 251. Hochstetter, F. (1944), Uber die Art und Weise, in welcher sich bei Sdugetieren und beim Menschen aus der sogenannten Riechgrube der Nasenhdohle entwickelt. z Anat Entwickl-Gesch, 113, 105. Hochstetter, F. (1950), Ueber die Beteiligung der Gesichtsfortsitze an der Bildung des primitiven Gaumens. Anat Anz, 97, 217. Houpt, M. I. (1970), Growth of the craniofacial complex of the human fetus. Am. J. Orthodont, 58, 373. Humphrey, T. (1968), The dynamic mechanism of palatal shelf elevation in human fetuses. Anat Rec, 160, 369 (abstr.). Humphrey, T. (1969), The relation between human fetal mouth opening reflexes and closure of the palate. Am J Anat, 125, 317. Iizuka, T. (1973), Stage of the closure of the human palate. Okajimas Folia Anat Jap, 50, 249. Iizuka, T. (1973), Stage of the formation of the human upper lip. Okajimas Folia Anat Jap, 50, 307. Inman, V. T. and Saunders, J. B. de C. M. (1937), The ossification of the human frontal bone, with special reference to its presumed pre- and post- frontal elements. J. Anat, 71, 383. Kato, K. (1953), Embryological studies on the devel- opment of the tooth in human embryo, with special reference to the formation of the tooth band and the lip furrow band. Shigaku (Den- tistry), 41, 3. (in Japanese with English abstract) Kernan, J. D. (1916), The chondrocranium of a 20 mm human embryo. J Morphol, 27, 605. Kraus, B. S. and Decker, J. D. (1960), The Prenatal inter-relationships of the maxilla and premaxilla in the facial development of man. Acta Anat, 40, 278. Latham, R. A. (1971), The development, structure and growth pattern of the human mid-palatal suture. | Anat, 108, 31. Lewis, W. H. (1920), The cartilaginous skull of a human embryo 21 mm in length. Carnegie Contr Embryol, 9, 299. Low, A. (1909), Further observations on the ossifica- tion of the human lower jaw. J Anat Physiol, 44, 83. Macklin, C. C. (1921), The skull of human fetus of 43 mm greatest length. Carnegie Contr Embryol, 10, 57. Mall, F. P. (1906), On ossification centers in human embryos less than 100 days old. Am | Anat, 5, 433. Mato, M., Aikawa, E. and Katahira, M. (1968), Further studies on “cell reaction” at the lower surface of the nasal septum of human embryos during the fusion to the palate. Acta Anat, 71, 154. Moffett, B. (1966), The morphogenesis of the tem- poromandibular joint. Am J Orthod, 52, 401. Noback, C. R. (1943), Some gross structural and quantitative aspects of the developmental anatomy of the human embryonic, fetal and circumnated skeleton. Anat Rec, 87, 29. Noback, C. R. (1944), The developmental anatomy of the human osseous skeleton during the em- bryonic, fetal and circumnatal periods. Anat Rec, 88, 91. Noback, C. R. and Robertson, G. G. 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