Dentistry

  General Embryology Fertilization Embryology Ø    A  phenomena which occurs before  birth Ø   Three basic events takes palce Ø    multiplication, differentiation and  degeneration.   Gametogenesis Ø Gametogenesis is maturation of primordial germ cells through meiosis. Primordial Germ cells,3 rd .week: Spermatogenesis: Oogenesis   Ø Oogenesis can be divided in three phases: A. Prenatal- 7 millions maximum by 5 th .  month. B. Postnatal C. Ovulation ● Ovulation  & menstrual cycle Ovulation when ? What is safe period ?   Corpus Luteum. Corpus luteum : Ø  What is it? a glandular structure. Ø   Function?  It secrets  progesterone . Ø   Fate:       a)  Corpus luteum of menstruation.           ( Corpus albicans)        b) Corpus luteum of pregnancy. Mens • Cyclic changes in the endometruim, comprising of  menstrual phase( 3-6) days, proliferative phase of (6-14 days, follicular cells- estrogen), secretory phase ( 15- 28 days- Corpus luteum-progesterone) and ischaemic ( premenstrual phase

White blood cells ·          Myeloid –         Myeloblast –         Promyelocyte –         Myelocyte –         Metamyelocyte –         Band –         Neutrophil,eosinophil, basophil •           Lymphoid –         Lymphocyte (B and T) and plasma cells –         Neoplastic proliferation of white cells Classification according to the origin of tumor cells: –         Lymphoid neoplasms •           Lymphocytic Leukemia •           Lymphoma (Hodgkin and non Hodgkin) •           Plasma cell dyscrasia –         Myeloid neoplasms •           Acute myelogenous leukemia •           Myelodysplastic syndromes •           Chronic myeloproliferative disorders –         Histiocytoses: proliferative lesion of macrophages and dendritic cells •           Langerhans cell histiocytoses Lymphoid Neoplasms •           Leukemia: lymphoid neoplasm characterized by a malignant neoplastic proliferation and accumulation of immature hematopoietic cells in the bone