Pierre Robin Sequence

Definitions

The Pierre Robin sequence (PRS) is a triad of congenital Congenital Chorioretinitis micrognathia (small lower jaw Jaw The jaw is made up of the mandible, which comprises the lower jaw, and the maxilla, which comprises the upper jaw. The mandible articulates with the temporal bone via the temporomandibular joint (TMJ). The 4 muscles of mastication produce the movements of the TMJ to ensure the efficient chewing of food. Jaw and Temporomandibular Joint: Anatomy), glossoptosis (retraction of the tongue Tongue The tongue, on the other hand, is a complex muscular structure that permits tasting and facilitates the process of mastication and communication. The blood supply of the tongue originates from the external carotid artery, and the innervation is through cranial nerves. Lips and Tongue: Anatomy into the pharynx Pharynx The pharynx is a component of the digestive system that lies posterior to the nasal cavity, oral cavity, and larynx. The pharynx can be divided into the oropharynx, nasopharynx, and laryngopharynx. Pharyngeal muscles play an integral role in vital processes such as breathing, swallowing, and speaking. Pharynx: Anatomy), and airway Airway ABCDE Assessment obstruction.

• Pierre Robin is a sequence, not a syndrome!
  • Sequence = a series of sequential Sequential Computed Tomography (CT) developmental malformations produced by a single cause
  • Syndrome = a group of signs and symptoms that occur together and that underlie a particular abnormality or condition
• Sequence progression: micrognathia → glossoptosis → airway Airway ABCDE Assessment obstruction
• Presents in an isolated form or as part of another syndrome (syndromic PRS), such as:
  • Stickler syndrome
  • DiGeorge syndrome DiGeorge syndrome DiGeorge syndrome (DGS) is a condition caused by a microdeletion at location q11.2 of chromosome 22 (thus also called 22q11.2 syndrome). There is a defective development of the third and fourth pharyngeal pouches, leading to thymic and parathyroid hypoplasia (causing T-cell immunodeficiency and hypocalcemia, respectively). DiGeorge Syndrome
  • Fetal alcohol spectrum disorder Fetal alcohol spectrum disorder Fetal alcohol spectrum disorder (FASD) is a group of neonatal pediatric disorders caused by maternal alcohol consumption during pregnancy. The term entails a range of physical and neurodevelopmental effects. Classification is based on severity and clinical presentation. Fetal Alcohol Spectrum Disorder
  • Treacher-Collins syndrome: Patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship with this syndrome also have mandibular hypoplasia Hypoplasia Hypoplastic Left Heart Syndrome (HLHS) but to different degrees than PRS.
  • Patau syndrome Patau syndrome Trisomy 13, or Patau syndrome, is a genetic syndrome caused by the presence of 3 copies of chromosome 13. As the 3rd most common trisomy, Patau syndrome has an incidence of 1 in 10,000 live births. Most cases of Patau syndrome are diagnosed prenatally by maternal screening and ultrasound. More than half of the pregnancies result in spontaneous abortions. Patau Syndrome (Trisomy 13)
  • Velocardiofacial syndrome Velocardiofacial syndrome Digeorge syndrome (DGS) is a condition caused by a microdeletion at location q11. 2 of chromosome 22 (thus also called 22q11. 2 syndrome). There is a defective development of the third and fourth pharyngeal pouches, leading to thymic and parathyroid hypoplasia (causing t-cell immunodeficiency and hypocalcemia, respectively). DiGeorge Syndrome
  • Beckwith-Wiedemann syndrome
  • CHARGE (Coloboma, Heart defects, choanal Atresia, Retarded growth and development, Genital abnormalities, and E ar AR Aortic regurgitation (AR) is a cardiac condition characterized by the backflow of blood from the aorta to the left ventricle during diastole. Aortic regurgitation is associated with an abnormal aortic valve and/or aortic root stemming from multiple causes, commonly rheumatic heart disease as well as congenital and degenerative valvular disorders. Aortic Regurgitation anomalies) syndrome
  • Cleft lip Cleft lip The embryological development of craniofacial structures is an intricate sequential process involving tissue growth and directed cell apoptosis. Disruption of any step in this process may result in the formation of a cleft lip alone or in combination with a cleft palate. As the most common craniofacial malformation of the newborn, the diagnosis of a cleft is clinical and usually apparent at birth. Cleft Lip and Cleft Palate and/or palate Palate The palate is the structure that forms the roof of the mouth and floor of the nasal cavity. This structure is divided into soft and hard palates. Palate: Anatomy

Epidemiology and Etiology

Epidemiology: 1 in 8,500–14,000 live births in the United States

Etiology:

• Deletions in the loci 4p, 4q, 6q, and 11q have been associated with micrognathia, which is believed to be the first step in this sequence of malformations. 
• Duplications in loci 10q and 18q have also been linked to micrognathia. 
• Some external factors during intrauterine life (e.g., oligohydramnios Oligohydramnios Oligohydramnios refers to amniotic fluid volume less than expected for the current gestational age. Oligohydramnios is diagnosed by ultrasound and defined as an amniotic fluid index (AFI) of ‰¤ 5 cm or a single deep pocket (SDP) of < 2 cm in the 2nd or 3rd trimester. Oligohydramnios) may play a role in micrognathia. 
• Isolated PRS is believed to arise sporadically via de novo mutations De novo mutations DiGeorge Syndrome in the SOX9 gene Gene A category of nucleic acid sequences that function as units of heredity and which code for the basic instructions for the development, reproduction, and maintenance of organisms. Basic Terms of Genetics/protein, which plays a critical role in skeletal development.
  • Familial cases of isolated PRS are rare and inherited autosomal dominantly.
• Syndromic PRS follows the same inheritance pattern as the associated syndrome.

Clinical Presentation

• Pierre Robin sequence consists of a triad:
  1. Micrognathia:
     • Hypoplastic abnormalities of the mandible Mandible The largest and strongest bone of the face constituting the lower jaw. It supports the lower teeth. Jaw and Temporomandibular Joint: Anatomy
     • Radiographic findings of micrognathia are the basis of the diagnosis
  2. Glossoptosis: abnormal placement of the tongue Tongue The tongue, on the other hand, is a complex muscular structure that permits tasting and facilitates the process of mastication and communication. The blood supply of the tongue originates from the external carotid artery, and the innervation is through cranial nerves. Lips and Tongue: Anatomy in the posterior part of the mouth/ pharynx Pharynx The pharynx is a component of the digestive system that lies posterior to the nasal cavity, oral cavity, and larynx. The pharynx can be divided into the oropharynx, nasopharynx, and laryngopharynx. Pharyngeal muscles play an integral role in vital processes such as breathing, swallowing, and speaking. Pharynx: Anatomy
  3. Airway Airway ABCDE Assessment obstruction:
     • The abnormal position of the tongue Tongue The tongue, on the other hand, is a complex muscular structure that permits tasting and facilitates the process of mastication and communication. The blood supply of the tongue originates from the external carotid artery, and the innervation is through cranial nerves. Lips and Tongue: Anatomy is responsible for airway Airway ABCDE Assessment obstruction.
     • Severe airway Airway ABCDE Assessment obstruction may result in hypoxia Hypoxia Sub-optimal oxygen levels in the ambient air of living organisms. Ischemic Cell Damage, cerebral impairment, and failure to thrive Failure to Thrive Failure to thrive (FTT), or faltering growth, describes suboptimal weight gain and growth in children. The majority of cases are due to inadequate caloric intake; however, genetic, infectious, and oncological etiologies are also common. Failure to Thrive. 
• Suprasternal retractions and the use of accessory muscles of respiration Respiration The act of breathing with the lungs, consisting of inhalation, or the taking into the lungs of the ambient air, and of exhalation, or the expelling of the modified air which contains more carbon dioxide than the air taken in. Nose and Nasal Cavity: Anatomy are common findings in infants with PRS, and are activated in an attempt to forcefully relieve the airway Airway ABCDE Assessment obstruction. 
• Pierre Robin sequence is also commonly associated with feeding difficulties, which lead to failure to thrive Failure to Thrive Failure to thrive (FTT), or faltering growth, describes suboptimal weight gain and growth in children. The majority of cases are due to inadequate caloric intake; however, genetic, infectious, and oncological etiologies are also common. Failure to Thrive and malnutrition Malnutrition Malnutrition is a clinical state caused by an imbalance or deficiency of calories and/or micronutrients and macronutrients. The 2 main manifestations of acute severe malnutrition are marasmus (total caloric insufficiency) and kwashiorkor (protein malnutrition with characteristic edema). Malnutrition in children in resource-limited countries.
• Commonly, the glossoptosis can produce a U- or V-shaped cleft palate Palate The palate is the structure that forms the roof of the mouth and floor of the nasal cavity. This structure is divided into soft and hard palates. Palate: Anatomy, as it impedes the fusion of the 2 palatal shelves.

Diagnosis and Management

Diagnosis

• Mainly based on the clinical assessment and radiographic findings of micrognathia
• Genetic testing Genetic Testing Detection of a mutation; genotype; karyotype; or specific alleles associated with genetic traits, heritable diseases, or predisposition to a disease, or that may lead to the disease in descendants. It includes prenatal genetic testing. Myotonic Dystrophies (e.g., fluorescence in situ hybridization Hybridization The genetic process of crossbreeding between genetically dissimilar parents to produce a hybrid. Blotting Techniques) is important to determine if PRS is isolated or associated with another syndrome.

Management

• Patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship with PRS may be treated non-surgically. 
  • Placement in the prone or lateral position will resolve the airway Airway ABCDE Assessment obstruction in two-thirds of cases. 
  • A nasopharyngeal tube Nasopharyngeal Tube ABCDE Assessment can be inserted to avoid frequent oxygen desaturation.
  • A nasogastric tube Nasogastric tube Malnutrition in children in resource-limited countries can be inserted for feeding assistance.
• Patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship who do not respond to these conservative measures should undergo surgical procedures to relieve the airway Airway ABCDE Assessment obstruction. 
  • Tongue-lip adhesion Adhesion The process whereby platelets adhere to something other than platelets, e.g., collagen; basement membrane; microfibrils; or other ‘foreign’ surfaces. Coagulation Studies
  • Distraction osteogenesis or mandibular distraction
  • Tracheostomy Tracheostomy Surgical formation of an opening into the trachea through the neck, or the opening so created. Laryngomalacia and Tracheomalacia (in severe cases)
• Patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship with cleft lip Cleft lip The embryological development of craniofacial structures is an intricate sequential process involving tissue growth and directed cell apoptosis. Disruption of any step in this process may result in the formation of a cleft lip alone or in combination with a cleft palate. As the most common craniofacial malformation of the newborn, the diagnosis of a cleft is clinical and usually apparent at birth. Cleft Lip and Cleft Palate and/or palate Palate The palate is the structure that forms the roof of the mouth and floor of the nasal cavity. This structure is divided into soft and hard palates. Palate: Anatomy may also require corrective surgical interventions.

Differential Diagnosis

The following conditions are differential diagnoses for isolated or syndromic Pierre Robin sequence:

• Velocardiofacial syndrome Velocardiofacial syndrome Digeorge syndrome (DGS) is a condition caused by a microdeletion at location q11. 2 of chromosome 22 (thus also called 22q11. 2 syndrome). There is a defective development of the third and fourth pharyngeal pouches, leading to thymic and parathyroid hypoplasia (causing t-cell immunodeficiency and hypocalcemia, respectively). DiGeorge Syndrome (Shprintzen-Goldberg syndrome): also called chromosome Chromosome In a prokaryotic cell or in the nucleus of a eukaryotic cell, a structure consisting of or containing DNA which carries the genetic information essential to the cell. Basic Terms of Genetics 22q11.2 deletion 22q11.2 deletion DiGeorge Syndrome syndrome, a disorder presenting with congenital Congenital Chorioretinitis heart disease, palate Palate The palate is the structure that forms the roof of the mouth and floor of the nasal cavity. This structure is divided into soft and hard palates. Palate: Anatomy abnormalities, immunologic dysfunction (e.g., autoimmune disease), hypocalcemia Hypocalcemia Hypocalcemia, a serum calcium < 8.5 mg/dL, can result from various conditions. The causes may include hypoparathyroidism, drugs, disorders leading to vitamin D deficiency, and more. Calcium levels are regulated and affected by different elements such as dietary intake, parathyroid hormone (PTH), vitamin D, pH, and albumin. Presentation can range from an asymptomatic (mild deficiency) to a life-threatening condition (acute, significant deficiency). Hypocalcemia, endocrine conditions (e.g., growth hormone deficiency), gastrointestinal problems, feeding difficulties, kidney malformations, hearing loss Hearing loss Hearing loss, also known as hearing impairment, is any degree of impairment in the ability to apprehend sound as determined by audiometry to be below normal hearing thresholds. Clinical presentation may occur at birth or as a gradual loss of hearing with age, including a short-term or sudden loss at any point. Hearing Loss, seizures Seizures A seizure is abnormal electrical activity of the neurons in the cerebral cortex that can manifest in numerous ways depending on the region of the brain affected. Seizures consist of a sudden imbalance that occurs between the excitatory and inhibitory signals in cortical neurons, creating a net excitation. The 2 major classes of seizures are focal and generalized. Seizures, minor facial abnormalities, and learning disabilities Learning disabilities Conditions characterized by a significant discrepancy between an individual’s perceived level of intellect and their ability to acquire new language and other cognitive skills. These may result from organic or psychological conditions. Relatively common subtypes include dyslexia, dyscalculia, and dysgraphia. DiGeorge Syndrome. 
• Stickler syndrome: a rare connective tissue Connective tissue Connective tissues originate from embryonic mesenchyme and are present throughout the body except inside the brain and spinal cord. The main function of connective tissues is to provide structural support to organs. Connective tissues consist of cells and an extracellular matrix. Connective Tissue: Histology disorder that presents as myopia Myopia Refractive Errors, retinal detachment Retinal detachment Retinal detachment is the separation of the neurosensory retina from the retinal pigmented epithelium and choroid. Rhegmatogenous retinal detachment, the most common type, stems from a break in the retina, allowing fluid to accumulate in the subretinal space. Retinal Detachment, hearing loss Hearing loss Hearing loss, also known as hearing impairment, is any degree of impairment in the ability to apprehend sound as determined by audiometry to be below normal hearing thresholds. Clinical presentation may occur at birth or as a gradual loss of hearing with age, including a short-term or sudden loss at any point. Hearing Loss, a characteristic facial appearance with mid-facial flatness, and joint pain Pain An unpleasant sensation induced by noxious stimuli which are detected by nerve endings of nociceptive neurons. Pain: Types and Pathways. Affected individuals may also have features of PRS (micrognathia, glossoptosis, and cleft palate Palate The palate is the structure that forms the roof of the mouth and floor of the nasal cavity. This structure is divided into soft and hard palates. Palate: Anatomy).
• Treacher-Collins syndrome ( mandibulofacial dysostosis Mandibulofacial dysostosis Treacher collins syndrome is a rare genetic condition with autosomal dominant inheritance. Treacher collins syndrome is also referred to as mandibulofacial dysostosis or franceschetti syndrome and is characterized by significant craniofacial deformities and conductive hearing loss. Treacher Collins Syndrome): a rare autosomal dominant Autosomal dominant Autosomal inheritance, both dominant and recessive, refers to the transmission of genes from the 22 autosomal chromosomes. Autosomal dominant diseases are expressed when only 1 copy of the dominant allele is inherited. Autosomal Recessive and Autosomal Dominant Inheritance condition characterized by significant craniofacial deformities and conductive hearing loss Conductive hearing loss Hearing loss due to interference with the mechanical reception or amplification of sound to the cochlea. The interference is in the outer or middle ear involving the ear canal; tympanic membrane; or ear ossicles. Hearing Loss. Treacher-Collins syndrome is strictly a physical disease; it does not affect Affect The feeling-tone accompaniment of an idea or mental representation. It is the most direct psychic derivative of instinct and the psychic representative of the various bodily changes by means of which instincts manifest themselves. Psychiatric Assessment cognition or other spheres of development. 
• Beckwith-Wiedemann syndrome: a cancer-predisposition disorder caused by changes on chromosome Chromosome In a prokaryotic cell or in the nucleus of a eukaryotic cell, a structure consisting of or containing DNA which carries the genetic information essential to the cell. Basic Terms of Genetics 11p15.5. Associated features include above-average birth weight (large for gestational age Gestational age The age of the conceptus, beginning from the time of fertilization. In clinical obstetrics, the gestational age is often estimated as the time from the last day of the last menstruation which is about 2 weeks before ovulation and fertilization. Pregnancy: Diagnosis, Physiology, and Care), macrosomia, macroglossia Macroglossia The presence of an excessively large tongue, which may be congenital or may develop as a result of a tumor or edema due to obstruction of lymphatic vessels, or it may occur in association with hyperpituitarism or acromegaly. It also may be associated with malocclusion because of pressure of the tongue on the teeth. Wilms Tumor, organomegaly, omphalocele Omphalocele Omphalocele is a congenital anterior abdominal wall defect in which the intestines are covered by peritoneum and amniotic membranes. The condition results from the failure of the midgut to return to the abdominal cavity by 10 weeks’ gestation. Omphalocele, umbilical hernia Umbilical Hernia A hernia due to an imperfect closure or weakness of the umbilical ring. It appears as a skin-covered protrusion at the umbilicus during crying, coughing, or straining. The hernia generally consists of omentum or small intestine. The vast majority of umbilical hernias are congenital but can be acquired due to severe abdominal distention. Abdominal Hernias, and/or diastasis recti.
• CHARGE syndrome CHARGE Syndrome CHARGE syndrome is a rare genetic condition with autosomal dominant inheritance in which almost all body systems are affected. The acronym CHARGE stands for the constellation of clinical features seen with this condition: Coloboma, Heart defects, Atresia choanae, Growth retardation, Genetic Abnormalities, and Ear abnormalities. CHARGE Syndrome: a rare genetic disorder in children that affects almost all body systems due to impaired gene Gene A category of nucleic acid sequences that function as units of heredity and which code for the basic instructions for the development, reproduction, and maintenance of organisms. Basic Terms of Genetics expression as a result of inherited mutations.
• Childhood sleep apnea Sleep apnea Repeated cessation of breathing for > 10 seconds during sleep and results in sleep interruption, fatigue, and daytime sleepiness. Obstructive Sleep Apnea: a sleep Sleep A readily reversible suspension of sensorimotor interaction with the environment, usually associated with recumbency and immobility. Physiology of Sleep disorder in which a pediatric patient’s breathing is partially or completely obstructed repeatedly during sleep Sleep A readily reversible suspension of sensorimotor interaction with the environment, usually associated with recumbency and immobility. Physiology of Sleep. While adult sleep apnea Sleep apnea Repeated cessation of breathing for > 10 seconds during sleep and results in sleep interruption, fatigue, and daytime sleepiness. Obstructive Sleep Apnea usually presents with fatigue Fatigue The state of weariness following a period of exertion, mental or physical, characterized by a decreased capacity for work and reduced efficiency to respond to stimuli. Fibromyalgia and daytime sleepiness Daytime sleepiness Narcolepsy and is due to obesity Obesity Obesity is a condition associated with excess body weight, specifically with the deposition of excessive adipose tissue. Obesity is considered a global epidemic. Major influences come from the western diet and sedentary lifestyles, but the exact mechanisms likely include a mixture of genetic and environmental factors. Obesity, childhood sleep apnea Sleep apnea Repeated cessation of breathing for > 10 seconds during sleep and results in sleep interruption, fatigue, and daytime sleepiness. Obstructive Sleep Apnea is more likely to present with behavioral disorders and is usually due to an enlargement of the adenoids and tonsils Tonsils Tonsillitis.
• DiGeorge syndrome DiGeorge syndrome DiGeorge syndrome (DGS) is a condition caused by a microdeletion at location q11.2 of chromosome 22 (thus also called 22q11.2 syndrome). There is a defective development of the third and fourth pharyngeal pouches, leading to thymic and parathyroid hypoplasia (causing T-cell immunodeficiency and hypocalcemia, respectively). DiGeorge Syndrome: a condition caused by a microdeletion at location q11.2 of chromosome Chromosome In a prokaryotic cell or in the nucleus of a eukaryotic cell, a structure consisting of or containing DNA which carries the genetic information essential to the cell. Basic Terms of Genetics 22. DiGeorge syndrome DiGeorge syndrome DiGeorge syndrome (DGS) is a condition caused by a microdeletion at location q11.2 of chromosome 22 (thus also called 22q11.2 syndrome). There is a defective development of the third and fourth pharyngeal pouches, leading to thymic and parathyroid hypoplasia (causing T-cell immunodeficiency and hypocalcemia, respectively). DiGeorge Syndrome is associated with defective development of the 3rd and 4th pharyngeal pouches Pharyngeal pouches Branchial Apparatus and Aortic Arches, leading to thymic and parathyroid Parathyroid The parathyroid glands are 2 pairs of small endocrine glands found in close proximity to the thyroid gland. The superior parathyroid glands are lodged within the parenchyma of the upper poles of the right and left thyroid lobes; the inferior parathyroid glands are close to the inferior tips or poles of the lobes. Parathyroid Glands: Anatomy hypoplasia Hypoplasia Hypoplastic Left Heart Syndrome (HLHS). Features also include congenital Congenital Chorioretinitis heart defects, characteristic facial features, cleft palate Palate The palate is the structure that forms the roof of the mouth and floor of the nasal cavity. This structure is divided into soft and hard palates. Palate: Anatomy, frequent infections Infections Invasion of the host organism by microorganisms or their toxins or by parasites that can cause pathological conditions or diseases. Chronic Granulomatous Disease, developmental delay, learning problems, and psychiatric disorders.
• Fetal alcohol spectrum disorders: a group of conditions that can occur in neonates whose mothers consumed heavy amounts of alcohol during their pregnancy Pregnancy The status during which female mammals carry their developing young (embryos or fetuses) in utero before birth, beginning from fertilization to birth. Pregnancy: Diagnosis, Physiology, and Care. Problems may include characteristic craniofacial changes, short height, low body weight, small head size, poor coordination Coordination Cerebellar Disorders, low intelligence, behavior problems, and problems with hearing or seeing. 
• Pectus excavatum Pectus Excavatum Cardiovascular Examination: a congenital Congenital Chorioretinitis malformation of the rib cage Rib cage The bony thoracic enclosure consisting of the vertebral column; the ribs; the sternum; and the costal cartilage. Chest Wall: Anatomy featuring a sternal depression usually beginning at the manubrium Manubrium The upper or most anterior segment of the sternum which articulates with the clavicle and first two pairs of ribs. Chest Wall: Anatomy and progressing down to the xiphoid process Xiphoid process Chest Wall: Anatomy. Can occur sporadically or be associated with connective tissue Connective tissue Connective tissues originate from embryonic mesenchyme and are present throughout the body except inside the brain and spinal cord. The main function of connective tissues is to provide structural support to organs. Connective tissues consist of cells and an extracellular matrix. Connective Tissue: Histology disorders (e.g., Marfan syndrome Marfan syndrome Marfan syndrome is a genetic condition with autosomal dominant inheritance. Marfan syndrome affects the elasticity of connective tissues throughout the body, most notably in the cardiovascular, ocular, and musculoskeletal systems. Marfan Syndrome).
• Cleft lip Cleft lip The embryological development of craniofacial structures is an intricate sequential process involving tissue growth and directed cell apoptosis. Disruption of any step in this process may result in the formation of a cleft lip alone or in combination with a cleft palate. As the most common craniofacial malformation of the newborn, the diagnosis of a cleft is clinical and usually apparent at birth. Cleft Lip and Cleft Palate and palate Palate The palate is the structure that forms the roof of the mouth and floor of the nasal cavity. This structure is divided into soft and hard palates. Palate: Anatomy: a congenital Congenital Chorioretinitis defect of the face that can include the upper lip Upper Lip Melasma and/or the palate Palate The palate is the structure that forms the roof of the mouth and floor of the nasal cavity. This structure is divided into soft and hard palates. Palate: Anatomy and that can be unilateral, bilateral, complete, or incomplete. A cleft lip Cleft lip The embryological development of craniofacial structures is an intricate sequential process involving tissue growth and directed cell apoptosis. Disruption of any step in this process may result in the formation of a cleft lip alone or in combination with a cleft palate. As the most common craniofacial malformation of the newborn, the diagnosis of a cleft is clinical and usually apparent at birth. Cleft Lip and Cleft Palate is caused by the failure of fusion of the maxillary prominence Maxillary prominence Development of the Nervous System and Face with the medial nasal prominence, while a cleft palate Palate The palate is the structure that forms the roof of the mouth and floor of the nasal cavity. This structure is divided into soft and hard palates. Palate: Anatomy is caused by the failure of fusion of the palatine prominences. Presents as difficulty with speech development, feeding, swallowing Swallowing The act of taking solids and liquids into the gastrointestinal tract through the mouth and throat. Gastrointestinal Motility, and tooth eruption, as well as visible malformation of the face.