maxillary and mandibular processes 2nd arch (hyoid) 3rd arch 4th arch 6th arch Derivatives of Pharyngeal Arches Maxillary process: forms maxilla, zygomatic and squamous part of temporal bone). Mandibular process: forms Meckel’s cartilage which give rise to malleus, incus, sphenomandibular and anterior lig. of malleus, part of mandible. N.B. rest of mandible formed by membranous ossification. Muscles supplied by mandibular nerve: Mastication muscles, myelohyoid, anterior belly of digastric, tensor tympani and tensor palati. • Mandibular • Maxillary • Chorda tympani (pretrematic nerve) Chorda tympani supplies anterior 2/3 of mucosa of tongue which is developed opposite the fist arch Reichert’s cartilage that forms stapes, stylohoid ligament, lesser horn and upper ½ of body of hyoid. Muscles supplied by facial nerve: Muscles of face and scalp, stylohyoid, posterior belly of digastric, platysma and stapedius Facial nerve Greater horn of hyoid and lower ½ of the body of hyoid Stylopharyngeus Glossopharyngeal Laryngeal cartilages Muscles of larynx, pharynx and soft palate Superior laryngeal Recurrent laryngeal
pouch Second pouch Third pouch Fourth pouch Dr. Sherif Fahmy Occupied by developing tongue. Tubo-tympanic recess that gives rise to middle ear & Eustachian tube Occupied by developing tongue Palatine tonsile Thymus gland Inferior parathyroid gland Ultimo-branchial body which form parafollicular cells in thyroid gland Superior parathyroid gland
fronto-nasal process. 2- Secondary palate: from palatine shelves of maxillary processes that form most of hard palate and soft palate. Hard palate receives downward growth of nasal septum.
swelling at line of fusions between processes of the face. 2- Oblique facial cleft: failure of fusion between maxillary prominence and lateral nasal fold (prominence). 3- Macrostomia or Microstomia : defective or marked fusion between maxillary and mandibular processes. 4- Cleft (hare) lip: cleft lip due to failure of fusion between maxillary process and intermaxillary segment. (lateral, bilateral or median) 5- Cleft palate: failure of fusion between different parts that form palate. It could be: A- Unilateral complete cleft palate. B- Bilateral complete cleft palate. C- Partial cleft palate. D- Cleft uvula.