Alveolar bone: Bony portion of each jaw that contains sockets for teeth

Amblyopia: Reduced vision without detectable change in appearance of eye

Anesthesiologist: Person who administers anesthetic

Ankylosis: Formation of a stiff joint

Anomaly: Deviation from normal

Anosmia: Lack of sense of smell

Anotia: Absence of the external ear

Anterior cranial fossa: Front portion of skull cavity upon which the brain's frontal lobes rest

Anterior fontanelle: Soft spot at the front of a young skull

Anterior open bite: Failure of front teeth to contact when jaws are closed

Anti-Mongoloid slant: Downward-sloping eyes

Apert syndrome: Abnormal head shape, small midface and fusion of fingers and toes

Aplasia: Lack of development of a body part

Asymmetry: Lack of symmetry; unequal opposite sides of the body that are normally alike

Atrophy: Wasting away

Audiologist: Person skilled in the study of hearing

Base of skull: Bony shelf on which the brain rests

Beckwith-Wiedemann syndrome: Large tongue, umbilical hernia, low blood sugar at birth, large birth weight, often port-wine stain between eyes

Bicoronal scalp flap: Scalp brought forward after incision from ear to ear behind the hairline

Bifid nose: Nose with central furrow producing two nose tips

Bifid uvula: Split uvula

Binder syndrome: Flattening around nose, often abnormal bite pattern

Binocular vision: Vision with both eyes

Bone graft: Piece of bone taken from one part and transferred to fill defect elsewhere

Brachycephaly: Short, wide head

Canthus: Angle at the inner or outer corner of the eyelids

Carpenter syndrome: Abnormal head shape, epicanthal folds, finger and toe problems

CAT/CTT scan: Computerized method of using X-rays to generate radiographic images

Cephalometric radiographs: X-ray images taken with patient in standard positions

Cerebrospinal fluid: Fluid circulating around brain and spinal cord

Class I malocclusion: Normal relationship of jaws but with crowding of teeth

Class II malocclusion: Lower arch teeth sit well behind upper arch teeth

Class III malocclusion: Upper arch teeth sit well behind lower arch teeth

Cleft lip: Congenital split in upper lip due to lack of fusion

Cleft lip and palate: Cleft involving the upper lip and roof of mouth

Cleft palate: Cleft of roof of mouth only

Cohen syndrome: Craniosynostosis with brachycephaly, hypertelorism and bifid nose

Coloboma: Notch in part of the eye, eyelid or nostril rim

Columella: Small column of tissue separating nostrils

Congenital: Present at birth

Cornea: Transparent front portion of the eye

Coronal suture: Line of junction between frontal and parietal bones

Cranial vault: Dome-like bony covering for the brain

Craniofacial: Pertaining to the head and face

Craniofacial surgeon: Plastic surgeon who specializes in surgery of the craniofacial region

Craniomaxillofacial: Pertaining to the head, upper jaw and face

Craniostenosis: Premature closure of multiple skull sutures

Crouzon syndrome: Craniosynostosis, facial deformity, abnormally protruding eyeballs

Diplopia: Double vision

Dystopia: Malposition

Embryology: The science of human development between about the 2nd and 8th week after fertilization

Encephalocele: Herniation of brain tissue through a defect in the skull

Enophthalmos: Backward displacement of the eyeball into the eye socket

Epibulbar cyst: Cyst on the eyeball

Epicanthal fold: Fold of skin covering inner corner of eye

Epiphora: Abnormal overflow of tears

Eustachian tube: Normal connection between middle ear and back of throat

Exophathalmos: Abnormal protrusion of eyeball

Facial nerve: Nerve controlling muscles of facial expression

Fibrous dysplasia: Overgrowth of abnormal bone

Fistula: Abnormal passage between two body parts

Fronto-orbital advancement: A surgical operation to advance the frontal bone and upper part of the orbits in one procedure

Frontal bone: Front part of skull

Frontal plagiocephaly: Flattening of forehead on one side due to premature fusion of coronal suture on that side

Frontal sinus: Air cavity in frontal bone

Geneticist: A specialist in the science of hereditary disease

Gingiva: Gum of the mouth

Goldenhar syndrome: Hemifacial microsomia, eye cysts, neck problems

Haemangioma: A collection of abnormal blood vessels

Hard palate: Bony roof of mouth

Hemifacial atrophy: Romberg syndrome, slow wasting of tissues on one side of face

Hemifacial hypertrophy: Enlargement of one side of face, sometimes enlargement of other body parts

Hemifacial microsomia: Small face on one side, associated deformed lower jaw, outer ear and facial soft tissues

Hydrocephalus: Abnormal collection of fluid within brain

Hypertelorism: Abnormally increased distance between eyes

Hypotelorism: Abnormally small distance between eyes

Intra-cranial pressure: Pressure between skull and brain

Lambdoid suture: Line of junction between parietal and occipital bones

Lateral canthus: Outer angle of eye

Le Fort: French surgeon who at the end of the 19th Century studied common facial fractures

Le Fort osteotomy: Surgical cut in midfacial bone in a similar direction to Le Fort fracture line

Macroglossia: Large tongue

Macrostomia: Abnormally wide mouth

Malocclusion: Malposition of teeth

Mandible: Lower jaw

Maxilla: Usually refers to the upper jaw bone that helps form the orbit, nasal cavity, palate and holds the upper teeth

Maxillary hypoplasia: Abnormally small maxilla

Maxillofacial technician: Person who produces appliances such as dental models, occlusal wafers and artificial teeth

Medial canthus: Inner angle of eye

Meningoencephalocele: Encephalocele, abnormal herniation of brain through a skull defect

Metopic suture: Line of junction of two halves of frontal bone

Microcephaly: Abnormally small head

Micrognathia: Very small jaw

Microsurgeon: A surgeon who operates on minute structures under a microscope (usually nerves, arteries and veins)

Middle ear: Portion of the ear behind the eardrum containing hearing bones, communicates with back of throat via eustachian tube

Nasendoscopy: Passage of a fiber-optic instrument through the nose to view back of throat

Neurofibroma: Abnormal overgrowth of nerve tissue to form a fleshy mass beneath skin

Neurofibromatosis: Multiple neurofibromas and skin pigmentation

Neurosurgeon: A surgeon who specializes in the diagnosis and surgical management of disorders involving the nervous system

Occipital bone: Bone at the back of the skull

Occipital plagiocephaly: Flattening on one side of occipital region

Occlusal plane: Plane between teeth with jaws brought together

Occlusal wafer: Flat U-shaped piece of plastic used to hold teeth in correct position during operation

Open bite: Inability of some teeth to contact when jaws are closed

Ophthalmologist: Eye specialist, a doctor who specializes in the diagnosis and management of eye disorders

Optic nerve: Major nerve between eye and brain, transmits vision signals

Oral cavity/mouth cavity orbit: Bony cavity that contains the eyeball

Orbital dystopia: Abnormal level of orbit

Orthodontist: A dentist who specializes in the development, prevention and correction of irregularities of the teeth and with associated facial abnormalities

Osteotomies: Surgical cuts made in bone

Otolaryngologist: A doctor who specializes in the diagnosis and management of diseases involving the ear, nose and throat (ENT)

Oxycephaly: Tall, pointed head

Parietal bone: Skull bone between frontal bone and occipital bone; the two parietal bones join at the sagittal suture

Periosteum: Membrane that covers bone and possesses bone-forming potential

Pfeiffer syndrome: Abnormal head shape, midface flattening, abnormal fingers and toes

Pharyngoplasty: An operation at the back of the throat to help overcome speech problems

Pierre Robin syndrome: Small lower jaw (cleft palate), cyanotic spells

Plagiocephaly: Asymmetrical head shape with flattening on one side

Plastic surgeon: A surgeon concerned with the restoration or improvement in the shape, function and appearance of body structures

Proptosis: Forward displacement of the eye

Prosthodontist: A dentist who specializes in the construction of artificial appliances to restore missing parts of the face and oral cavity

Psychiatrist: A doctor specializing in the study and treatment of abnormal (and normal) thinking patterns

Psychologist: A person involved in the study of mind processes in relation to behavior

Pupil: Opening in the middle of the eye, appears as a black dot

Radiographer: A person who uses X-rays to take films of the body

Radiologist: A doctor who analyzes radiographs for the diagnosis of body problems

Romberg syndrome: Progressive wasting of soft tissues on one side of the face (hemifacial atrophy)

Saethre-Chotzen syndrome: Premature fusion of the skull’s bony plates with skull and facial asymmetry

Sagittal suture: Line of junction of parietal bones

Scaphocephaly: Long boat-shaped head resulting from premature fusion of the sagittal suture

Skull base: Floor of skull cavity on which the brain rests

Sleep apnea: Periodic absence of breathing during sleep

Social worker: A person involved in the study of people’s social interactions and employment background

Soft palate: Mobile, muscular back part of the palate

Speech pathologist: A person involved in the study and treatment of speech problems

Squamosal suture: The line of junction between the temporal bone and the parietal bone

Strabismus: Squint, abnormal alignment of axes of the eyes

Strawberry naevus: A small, red bulging collection of blood vessels under the skin that has the appearance of a strawberry

Subcranial operation: A surgical procedure that does not involve opening the skull

Supra-orbital ridges: Bony prominences at upper border of eye sockets

Syndactyly: Fusion of fingers or toes

Syndrome: A group of characteristics that occur together

Temporal bone: One of the bones forming part of the lateral surface and base of the skull, containing the hearing apparatus

Temporomandibular joint: Position at which lower jaw pivots on the base of the skull, just in front of ears

Tessier, Paul: French plastic surgeon who pioneered craniofacial surgery

Tessier clefts: Numbering system to classify clefts involving facial structures

Trachea: Windpipe

Tracheostomy: Surgical opening in the trachea to assist breathing

Transcranial: An operation that involves the skull being opened

Treacher Collins syndrome: Dominantly inherited condition involving small cheekbones and lower jaw, commonly with hearing problems

Trigonocephaly: Premature fusion of the two halves of the frontal bones at the metopic suture

Tumor: Local swelling from abnormal growth

Tympanic membrane: Eardrum

Uvula: Pendant fleshy part of soft palate

Velo-pharyngeal incompetence: Inability of the velo-pharyngeal sphincter to close normally during speech

Von Recklinghausen syndrome: Neurofibromatosis, Elephant Man’s disease, multiple nerve tumors and patches of pigmentation

Zygoma: Cheekbone