2016 Glossary - 35
herpetiform adj: lesions that resemble herpetic (herpes) lesions.
heterograft n: a tissue graft where the species of the
donor and recipient are different. Also known as a
heterotopic pain n: pain felt in a site distant from the
site of origination. See also referred pain.
high lip line n: an extreme elevation of the inferior border of the upper lip whereby all the maxillary teeth
and part of the alveolar process are visible while naturally smiling.
high noble metal alloy n: a dental casting alloy composed of a minimum of 60% noble metal (gold, platinum, palladium, rhodium, ruthenium, iridium, osmium) by weight with at least 40% gold as classified by
the American Dental Association.
hinge axis n: an imaginary line created by rotation of
the mandible through the sagittal plane.
hinge joint n: a joint that allows movement in only
1 plane, such as a door hinge. See also ginglymus
hinge position n: orientation of parts allowing hinge
movement between them.
histopathology n: the cytologic and histologic study
of disease at the microscopic level.
homograft n: a type of tissue graft where the donor
and recipient are of the same species. See also allograft.
hybrid denture n: slang for any dental prosthesis that
has been changed from the usual form.
hybrid prosthesis n: slang for any prosthesis, such as
fixed dental prostheses, removable dental prostheses, or maxillofacial prostheses, that does not follow
traditional design. Often it is used to designate a
dental appliance made of various materials, various
types of denture teeth (porcelain, plastic, composite), acrylic denture resins of variable nature, or differing metals or designs.
hydroxyapatite n: an inorganic compound,
Ca5(PO4)3(OH), found in the mineralized matrices
of bone and teeth that provides hardness to these
structures. Various synthetic forms are used in ridge
augmentation and intrabony defects, as well as coating of dental implants.
hydroxyapatite ceramic n: a synthetic composition of
calcium and phosphate in physiologically acceptable
ratios. It is a rigid, nonresorbable, biocompatible material used for dental implants and augmentation of
deficient alveolar ridges.
hygienic (sanitary) pontic n: a pontic (suspended
crown in a fixed bridge) that is simpler to clean because it has a rounded or bullet-shaped cervical form
and does not contact the edentulous ridge.
hypalgesia (hypoalgesia) n: reduced sensitivity to pain
that results from a raised pain threshold.
hyperalgesia n: amplified sensitivity or sensibility to
pain that results from a lowered pain threshold.
hyperbaric chamber n: an enclosed space or tube that
accommodates a patient and subjects the patient to
ambient gas pressures >1 atm.
hyperbaric oxygenation n: the administration of oxygen in an enclosed space larger than atmospheric
pressure; also called hyperbaric oxygen therapy.
hyperemia n: an extreme accumulation of blood in a
tissue due to vascular engorgement.
hyperesthesia (hyperaesthesia) n: an abnormal increase in sensitivity to sensory stimulation.
hyperglycemia n: a condition characterized by an unusually increased or high blood glucose, typically
>11.1 mmol/L, however, symptoms may not be noticeable until even higher values are reached, such
as 15-20 mmol/L. A patient with a consistent range
between ~5.6 and ~7 mmol/L is considered hyperglycemic, values >7 mmol/l are considered a state
of diabetes. Chronic levels >7 mmol/L can produce
hyperkeratosis n: extreme development of keratin by
hypermineralization n: abnormal quantities of mineral elements in calcified tissue.
hyperosmia n: an uncharacteristically increased sensitivity to odors.
hyperostosis n: a limited overgrowth of bone in one