The maxillary sinus is a pyramidal-shaped cavity and is the largest of
the paranasal cavities. The maxillary sinus borders are comprised of 1)
the nasal cavity medially, 2) the floor of the ocular orbit superiorly,
3) the maxillary tuberosity posteriorly, 4) the canine fossa anteriorly,
and 5) the apical portion of the alveolar process inferiorly. During the
aging process, and to a greater degree, after the loss of posterior
teeth, the maxillary sinuses progressively increase their volume at the
expenses of the superior-posterior alveolar ridge, which can complicate
or impede dental implant placement. To overcome this problem, the bone
augmentation technique known as sinus lift or maxillary sinus
augmentation (MSA) was introduced in 1970. This surgical procedure, and
in particular, the lateral approach, has remained essentially unchanged
in its execution protocol since it was first described. However, the
procedure now exists as a one or two stage variant depending on whether
the implants are placed simultaneously or consecutively to augmentation.
The , although rather invasive, appears to be the most successful among
the intra-oral bone augmentation techniques, with an implant survival
rate comparable to implants placed in native bone. The low frequency of
reported post-operative infections, which is reported to be between 2%
and 5.6%, contributes to safety and effectiveness of the procedure.
However, sinus infections can still occur. An infection of the maxillary
sinus can remain localized or spread to neighboring structures, leading
to life threatening scenarios if not properly treated. For this reason,
it is recommended to follow specific pharmacological protocols to
prevent such consequences.
Currently, pre- and post-operative prophylaxis regimens for MSA
procedures include the use of antibiotics. However, corticosteroids are
less commonly used, and if so, are generally administered only pre- or
peri-operatively via oral or intramuscular route. This decision is
operator-dependent and is not as standardized as antibiotics.
The use of corticosteroid drugs in oral surgery is much debated; those
who use them aim to reduce the direct effects of inflammation on
post-operative symptoms such as edema. This is because corticosteroids
decrease the activity and migration of inflammatory cells (T helper
lymphocytes, monocytes, and macrophages) on the site of trauma and their
production of pro-inflammatory substances (histamine, leukotrienes,
prostaglandins, and cytokines). Furthermore, the inhibition of enzyme
phospholipase A2 and prostaglandin production makes
corticosteroids a potent analgesic substance, which reduces
post-operative pain.
A challenging factor regarding MSA-related complications is that the
post-operative infections can be either true sinus infections (i.e.,
acute sinusitis) or bone graft related infections (i.e., bacterial
contamination of graft). A sinus infection is distinguished from a bone
graft infection in that it occurs within the sinus space surrounded by
the Schneiderian membrane (SM) versus a bone graft infection which is
found between the inferior aspect of the SM and the apical portion of
alveolar process.
In light of these considerations, the purpose of this systematic review
is to identify whether the administration of corticosteroids during the
MSA surgical procedure operative phase affects post-operative symptoms,
including swelling, pain, and infection rate.