are inlays and onlays?
Inlays are more like
fillings than onlays. As mentioned, they’re made in a dental lab after
your dentist has removed the decay. Inlays are generally more durable and far
out-last fillings. They can be fabricated from tooth-colored composite resin,
porcelain or gold. They are also more conservative than crowns. Generally, much
less tooth structure is removed in the preparation of inlays than crowns.
Onlays are essentially identical to inlays with the
exception that one or more cusps have been included
in the preparation. In other words, decay or
trauma has affected the cusps, necessitating
their replacement. Onlays may be composed of
the same materials as inlays - tooth - colored
composite resin, porcelain or gold. They are
sometimes also referred to as partial crowns.
and onlays are used to replace damaged areas of
the tooth, and can be made of porcelain, gold or
composite resin. An inlay, which is similar to
a filling, is used inside the cusp tips of the
tooth. An onlay is a more substantial reconstruction,
similar to the inlay but extending out over one
or more of the cusps of the tooth.
Traditionally, gold has been the material of choice
for inlays and onlays, however porcelain has become
increasingly popular due to its strength and white-colored,
which can closely match the natural color of your
How are they applied?
Inlays and onlays require two appointments. During
the first visit, the filling being replaced or
the damaged or decaying area of the tooth is
removed, and the tooth is prepared for the inlay
or onlay. To ensure proper fit and bite, an impression
of the tooth is made by the dentist, and sent
to a lab for fabrication. The dentist will then
apply a temporary filling on the tooth and schedule
the next appointment.
At the second appointment, the temporary filling
is removed and we will make sure that the inlay
or onlay fits correctly. Once the correct fit is
achieved, the inlay or onlay is bonded to the tooth
with a very strong resin and polished to a smooth
an anesthetic will be given to numb the area;
and onlays are applied in two visits. On the
any old filling material and/or decay will
- An impression will be taken to record
the shape of the tooth being repaired and the
teeth around it.
- A temporary filling will be applied
to protect the tooth while you wait for your
restoration to be made;
- At the second appointment after your
restoration has come back from the lab, your
dentist will cement it in place; small adjustments
may need to be made so that the tooth is comfortable
to bite on.
Depending on their size and location, fillings
can reduce the strength of a tooth by up to 50%.
Inlays and onlays, on the other hand, can actually
increase the strength of the tooth by up to 75%.
Inlays and onlays are fabricated outside of the
mouth and therefore are capable of being made much
stronger than typical fillings. They typically
last between 10 to 30 years.
Porcelain Inlays (Ceramic Inlays)
Ever more patients express the wish to replace their
old amalgam fillings with a biocompatible and durable
material. From an aesthetic view, ceramic inlays
are regarded as the top of all available alternatives.
For many years, gold inlays have been the tried and
tested solution and have a long lifespan. Today,
aesthetic awareness has led to a decline in their
Before – amalgam
After – ceramic
inlay and onlay
What are the
advantages of porcelain inlays?
Ceramic inlays have no metal core and are therefore
translucent. They are bonded to the tooth using
a special adhesive method, leaving no marginal
gaps. A chemical bond is created between tooth
and ceramic, restoring weakened teeth to their
original strength. The high translucency yields
an exceptional aesthetic quality. Ceramic is exceedingly
biocompatible. For example, allergies such as to
certain alloys are unknown.
Ceramic inlays are long-lasting. The following
diagram shows the longevity comparison between
composite fillings and ceramic inlays.