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This page includes a
collection of frequently occurring terms, used in this
web site. Most of these terms are dental or medical in
nature and are just briefly explained in ‘plain
English’.
Abutment
– usually some metal or ceramic piece that is machined
and attached to the implant fixture. There are several
types of abutments; each designed for a specific task.
Some are designed to heal or shape tissues after the
Uncovery procedure (Healing
Abutments) , others are designed to ‘carry’ the crowns
for the implants, yet others are designed to secure
different types of implant restorations.
Adrenal Insufficiency
– a condition where the medulla and/or the cortex of the
adrenal gland is compromised in its production of
epinephrine, norepinephrine, cortisol, corticosterone
and aldosterone. Cortical insufficiency produces a
clinical condition called “Addison’s Disease”,
characterized by extreme weakness, low blood pressure
and pigmentation of the skin. If severe enough,
elective surgery such as implant surgery may not be
indicated.
Amalgam - A "silver filling"
is a euphemism for an amalgam restoration, which a
dentist places in a patient's tooth after a cavity is
created by drilling out decay. Amalgam restorations
consist of mercury, silver, tin, copper, and a trace
amount of zinc. The dental amalgam has two fundamental
flaws that adversely effect a patient's health. The
first fundamental flaw is that all amalgam metals are
cations. The net result of the tendency for covalent,
ionic and metallic bonding and van der Waals forces
between amalgam cations is a weak repulsion. So there is
a sustained release of mercury and other metals from the
amalgam into the body. Researchers have measured a daily
release of mercury on the order of 10 micrograms from
the amalgam into the body. It has yet to be
determined that this concentration has a negative
systemic health effect
Anemia
– indicates a quantitative deficiency of hemoglobin and
usually also a corresponding decrease of red blood
cells. There are several classifications of anemia,
however they all have a decreased healing potential in
common. Again, depending on the severity of the
condition, elective surgery such as implant surgery may
not be indicated.
Aortitis
– an inflammation of the aorta or other arteries. The
acute variety may arise from bacterial infections and
carry along complications such as thrombosis, rupture
with hemorrhage and aneurysms. The chronic variety may
often be seen in tuberculosis and syphilis. This, in
turn, may lead to necrotizing and fibrosing
inflammation, which may compromise the structural
integrity of blood vessels.
Aortic Aneurysm
– a localized, abnormal and persistent dilation of a
section of the aorta. This usually results from a
weakness in the vessel wall. If severe enough, rupture
of the aorta with severe hemorrhage is a potential
hazard.
Arteriosclerosis
– literally means ‘hardening of
the arteries’ and is often used synonymously with
‘atherosclerosis’. There is only a histologic
difference between the two, depending on which layer of
the artery wall is involved. Arteriosclerosis itself is
characterized by thickening of the artery wall, and
simultaneous decrease of the inside diameter (lumen) of
the artery, thus compromising blood flow and increasing
the blood pressure.
Autogenous Bone
– bone harvested for grafting purposes from a donor site
(usually a different part of the jaw of the hip bone)
within the same individual. It is considered the ‘Gold
Standard’ to which all other bone graft materials are
compared.
Blade Implant - (Endosseous
Blade Implant) Their name is derived from their flat,
blade-like (or plate-like) portion, which is the part
that gets embedded into the bone. Blade implants
are not used too frequently any more, however they do
find an application in areas where the residual bone
ridge of the jaw is either too thin (due to resorption)
to place conventional Rootform Implants or certain vital
anatomical structures prevent conventional implants from
being placed.
Bone Morphogenic Proteins (BMPs)
– endogenous family of proteins belonging to the ‘Growth
Factor’ group. BMPs were isolated and later produced
via recombinant gene technology in order to find a bone
graft substitute closely matching, if not improving the
qualities of autogenous bone. Several variations
(fourteen) of BMPs were isolated so far; two of which
may find great potential in future bone grafting
procedures.
Bone Grafting
– the process of augmenting a bone deficient site or
area with more bone. The bone graft can be autogenous,
allogenic, xenogenic or alloplastic in nature (see <Bone
Grafting>). Recently Growth Factors (above) have also
entered the scene for potential graft material.
Bridge
– a fixed prosthesis designed to replace missing teeth.
A conventional bridge uses the teeth adjacent to the
edentulous (toothless) site as anchorage to suspend the
missing tooth. All teeth in a bridge are usually
splinted together. An implant bridge may sometimes not
suspend a missing tooth, but rather splint all teeth,
which are attached to implants together, in order to
improve the biomechanical loading characteristics of the
implant fixtures.
Composite - is a dental
material which consists of high molecular
weight monomers that when cured create rigid
cross-linked polymers - basically, dental composite is a
plastic.
CT Scan
– an x-ray machine that can deliver sectional x-ray
pictures in small intervals in three different
dimensions (panoramic, cross-sectional, and axial).
Three-dimensional pictures can also be generated from
the CT-Scan data. In addition to that CT-Scanners also
have the ability to measure bone and tissue density,
based on “Houndsfield” units.
Dental Implant
– a device placed into or on top of the jaw bone to
provide support and/or retention for a dental
restoration or prosthesis (see the
Dental
Implants section for more details).
Denture
– (a.k.a. Full Denture) a removable prosthesis or
appliance designed to replace all the missing teeth in
the upper as well as the lower jaw. A denture is only
supported by the soft tissues in the mouth and, thus,
does not offer great stability and/or chewing power.
Diabetes
– a.k.a.
Diabetes Mellitus
is a disease caused by an absolute or relative
deficiency of the hormone insulin. This, in turn, gives
rise to a disturbance in carbohydrate metabolism, the
inability to store glycogen in the liver, excessive
glucose in the blood and urine, acidosis and disturbance
in protein metabolism. The latter can be a factor
responsible for poor wound healing.
Foramen
– a hole in a bony structure, through which nerves, and
blood vessels either enter or exit. Foramina (pl.) are
used in surgery as anatomical landmarks.
Fibrous Dysplasia
– a developmental defect mainly involving bone.
Symptoms usually include pain, disability and deformity
of limbs, usually beginning in early childhood. The
abnormal bone formation may reduce the success rates for
dental implants.
Healing Abutment or
Collar – an
Abutment (see above) placed on
implants after the Uncovery
procedure (see below). Its purpose is to create an
emergence profile in the gum tissues for the future
implant crown. Sometimes the healing abutments are
replaced with temporary crowns instead.
Hemophilia (Factor VIII, IX, X,
XII) – an inherited
abnormality of the blood appearing only in the male
population. The coagulation time of the blood is
prolonged, despite the fact that bleeding time,
prothrombin time, platelet count and tourniquet tests
are normal. In the classical hemophilia (caused by a
deficiency in Factor VIII) severe and prolonged
hemorrhages can follow trivial injuries. This can pose
a management problem during elective-type surgeries.
Histiocytosis X
– a condition where diffuse hyperplasia of certain
tissues involves organs such as spleen, liver, lungs,
bone marrow and lymph nodes. This condition is more
frequent in infants and little children.
Hydroxylapatite
– (HA) with respect to dental implants, a coating bonded
to the titanium surface of an implant in order to
enhance its ability to fuse to bone faster.
Hypothyroidism
– a condition where insufficient function of the thyroid
gland produces a general retardation of physical growth
and depressed metabolism.
Implant Dentistry -
a specialized field of dentistry, dealing
with the placement and / or restoration of dental
implants.
Lymph Nodes -
Lymph nodes are glands that play
an important part in your body's defense against
infection. They produce lymph, which travels throughout
your body in the lymph system, and filters impurities in
your body.
Mallet
– a surgical instrument in the shape of a
double-ended blunt hammer, used to drive other surgical
tools or devices into bone.
Membrane
– in the field of dental implant surgery it is referred
to a little ‘sheet’ made up of different materials (GoreTex,
Collagen etc.) and designed to protect a grafted bone
site from influx of soft tissue cells. Soft tissue
cells would compromise bone healing, since they
proliferate at a faster rate than bone cells.
Oral Implantology
– (an older term for Implant Dentistry) a specialized
field of dentistry, dealing with the placement and
restoration of dental implants.
Orthognathic Surgery
-
Orthognathic surgery involves the surgical manipulation
of the elements of the facial skeleton to restore the
proper anatomic and functional relationship in patients
with dentofacial skeletal anomalies.
Osseointegration
– the ‘fusion’ of the surface of a dental implant to the
surrounding bone, so that it is secured tightly in the
bone and ready to be used as an anchor for a tooth.
Once a dental implant is "osseointegrated" or
"integrated" it can not be removed from the surrounding
bone without fracturing the bone interface. A
microscopic image of an integrated implant can be seen
here.
Overdenture
– much like a conventional denture, except for some
attachment mechanism built in, giving it better
retention. Overdentures can be made for implants as
well as for some remaining natural teeth.
Paget’s Disease
– a condition where the existing bone is resorbed with
simultaneous overgrowth of new, poorly calcified,
irregular bone. This type of bone may not have enough
density for proper integration of dental implants.
Para-nasal Sinuses
– two air filled bony sacks or cavities on each side of
the nose. Phylogenetically a remnant from our marine
origin, the para-nasal sinuses grow larger in volume as
we get older (they undergo pneumatization). Each sinus
has a direct communication with the nose via an opening
called the ostium.
Peri-Implantitis
– an inflammatory condition around dental implants,
often associated with some bone loss. Peri-implantitis
can be compared to periodontits in natural teeth.
Periodontics
– a specialized field of dentistry,
mainly dealing with the repair and maintenance of the
supporting tissues (gums and bone) around teeth.
Many periodontists also place dental implants.
Prosthesis
– with respect to dentistry, any type of appliance that
replaces actual missing teeth. This can range from a
bridge, replacing a single missing tooth to a removable
appliance, such as a denture, replacing all missing
teeth.
Removable Partial
Denture – a removable
appliance or prosthesis, which typically attaches to
selected teeth in the mouth and replaces usually several
missing teeth.
Ramus Frame Implant
- are long cross-arch bar implants, which belong in the
category of endosseous implants, although their
appearance might not suggest that at first. These
implants are designed for the toothless lower jaw only
and are surgically inserted into the jaw bone in three
different areas: the left and right back area of the jaw
(the approximate area of the wisdom teeth), and the chin
area in the front of the mouth. Only on implant is
placed for a lower jaw. The part of the implant
that is visible in the mouth after the implant is placed
looks similar to that of the Subperiosteal Implant
described below.
Rootform Implant -
Rootfrom implants have become the most popular implants
in the world today. Rootform implants are also
categorized as endosseous implants. These implants come
in a variety of shapes, sizes, and materials and are
being offered by many different companies worldwide.
They are all somewhat cylindrical in shape. Some
clinicians regard them to be the “Standard of Care” in
Implant Dentistry.
Sarcoidosis
– a systemic, granulomatous disease involving several
organs as well as bone marrow. Heavy involvement of the
heart and lung tissues as well as the immune system may
make a patient with sarcoidosis not an ideal candidate
for elective surgeries.
Subperiosteal Implant
- Subperiosteal Implants were already introduced in the
1940s. These implants are also cross-arch implants, so
that only one implant is needed for the entire dental
arch. Of all currently used devices, it is the
type of implant that has had the longest period of
clinical trial. These implants are not anchored inside
the bone, such as Endosseous Implants, but are instead
shaped to "ride on" the residual bony ridge of either
the upper or lower jaw.
Template (surgical) - a
surgical guide that helps placing implants in their
proper position, angulation and trajectory in reference
to the final restoration. It is usually made out
of clear acrylic, and and shows the position of the
"future" teeth.
Temporary Prosthesis or Crown
– a prosthesis (crown, bridge, denture, etc.) used for
temporary purposes until the final prosthesis is ready
to be used.
Titanium
– although by some considered an exotic metal it is
actually on of the most abundant elements on earth.
However, it took scientific advances of modern
metallurgy to turn this black sand into useful metal.
Commercially pure titanium comes in four different
grades (1-4), grade four being the finest. Most dental
implants are either machined out of commercially pure
titanium or an alloy thereof. The most frequently used
alloy is Ti Al6V4.
This alloy improves the fracture resistance of titanium
and does not compromise the
Osseointegration (see above) into bone.
Tuberculosis
– caused by
Mycobacterium tuberculosis,
stimulating specific tissue reactions resulting in
necrosis. The lung is the organ most frequently
affected, but other organs are also commonly involved.
If the respiratory system is severely compromised, blood
oxygen levels may drop and make surgical management more
complicated.
Uncovery
– a small surgical procedure done, in order to expose
the head of the implant and connect a healing
Abutment or temporary prosthesis
(see above). This is usually done after the implant has
“matured” in the bone for several months. Some implants
are designed to remain exposed in the mouth right after
they are placed, abolishing an uncovery procedure all
together.
Vasoconstrictor
– a chemical substance that
triggers constriction of blood vessels (usually
arterioles, limiting blood flow through these vessels.
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