Dinh X. Bui, D.D.S., M.S.
is Sinus Lift?
Sinus Lift is a procedure of which the maxillary sinus membrane
is elevated and subantral augmentation is performed with bone
graft placement. The end result is the improved bone height
in the posterior maxilla which is more favorable for implant
Usually, when tooth is lost, pneumatization (referred to the
phenomena which the volumn of sinus cavity increase due to
the bone loss at the base of sinus and the sinus membrane
relocated to more apical) of the maxillary sinus occurs. The
loss of teeth results in alveolalr resorption, decrease in
bone width and height, and decrease in bone density. When
implant is inserted in this area, the initial implant stability
is poor coupling with inadequate bone height for the implant
length. This result in implant failure either initially or
Where is the maxillary
sinus and what is its function?
The maxillary sinus is the largest of four
paranasal sinus. It appears as a pyramid of four thin, bony
walls, the base of which faces the lateral nasal wall and
the apex of which extends toward zygomatic bone. The antrum
is approximately 34 to 35mm at its base, and the apex extends
23mm toward the zygomatic area. The average volume is 15mL
and increases as posterior tooth loss and pneumotization occurs.
Bony septa joining medial and lateral walls may complicated
the sinus lift procedure as potential for sinus membrane perforation
at these areas.
Pathologically, sinusitis has been related often to maxillary
or frontal sinus involvement. Other problems identified with
lesser encounter includes tumors and malignancy. 60% of squamous
cell carcinomas of the paranasal sinuses located in the maxillary
sinus, usually in the lower half of the spectrum. Other iatrogenic
incidence would be oroantral fistulas as the consequence of
the tooth or implant extraction, trauma, or surgical entry
into the maxillary sinus. Because of anatomic proximity of
the sinus and oral cavity, many oral diseases also extend
into the sinus such as periapical, follicular, and odontogenic
keratocysts, fibrous dysplasia, ossifying fibromas, and giant
cell lesions. Other cystic lesions such as pseudocysts, retention
cysts, and/or mucocele may be diagnosed in the area.
- Upper left: maxillary sinus in relation to the skull
- Upper right: close up view of maxillary sinus
- Lower left: maxillary sinus in relation to the teeth,
noted the root proximity of posterior teeth to the sinus
- Lower right: interior view of maxillary sinus, the
lateral wall is carefully section and lift up to see the
inside of the sinus cavity. The sinus membrane lines the
cavity. Note the ostium where the sinus drainage occurs.
How is the maxillary
sinus bone height influence the implant placement process?
Carl Misch subcategorized
the implant treatment planing into four approaches bases on
bone height in the posterior area:
- Subantral Option 1(SA1), conventional
implant placement: there is sufficient available bone height
(greater than 12mm) to permit the placement of endosteal
implant. No lift required in this category as implant can
be placed normally. Bone graft may be used to augment the
bone width. In my opinion, whenever bone graft is placed,
barrier should be considered as to inhibit connective tissue
migration into the area and allow the bone cells to migrate,
differentiated, and mature at the bone site.
- Subantral Option 2(SA2), subantral lift and simultaneous
implant placement with osteotome lift technique: there is
8mm-12mm available bone height, thus we need probably only
2-3mm more to properly place a 13mm length implant in the
area. 13mm or more implant length is preferred due to numerous
studies (Hurztler et al) which shows the implant success
in relative to length (or surface area). Osteotome lift
technique is used of which the implant is tapped and produced
a green stick fracture on the sinus floor. Bone graft can
be added and further elevates the sinus membrane. (Please
select Implant, Osteotome Lift under service menu for more
- Subantral Option 3(SA3), sinus membrane elevation
with subantral augmentation and simultaneous endosteal implant
placement: there is only 5mm-8mm bone height of vertical
bone and sufficient width are present between the antral
floor and the crest of residual alveolar ridge. A Tatum
lateral wall approach is performed just superior to the
residual alveolar bone. Green stick fracture introduced
in the access window as it is rotating inward and upward
and served as the floor of the implant. A mixture of autogenous
bone and/or allograft material is placed into the area previously
occupied by the sinus cavity. Implant is then placed from
the top of the ridge, through the 5mm bone height, and into
the graft area. A barrier membrane (please select Guided
Tissue Regeneration under services menu) placed at the
window opening, and flap closure.
- Subantral Option 4(SA4), sinus membrane elevation
and subantral augmentation with no implant placement: there
is 4mm or less of bone height and thus there is not enough
surface area for anchorage and stabilization of the implant.
In this case, Tatum lateral wall approached is performed
just superior to the residual alveolar bone.Green stick
fracture introduced in the access window as it is rotating
inward and upward and served as the floor of the implant.
A mixture of autogenous bone and/or allograft material is
placed into the area previously occupied by the sinus cavity.
Implant will be placed at 8 to 12 months later as the new
bone is allowed to migrate, differentiate, and mature.
What are the contraindication
to the sinus lift procedure?
Any sign of sinusitis will delay the surgical appointment.
If the patient shows any sign of nasal congestion, sinusitis,
rhinitis, or upper respiratory tract disease, the surgery
should be postponed until the situation resolves. Patient
should be aware of sinus drainage, or any kind of health
problem leading to inflammation of sinus membrane (fever,
cold, flu, allergy, drainage, polypse). Moreover, patient
must not have UNCONTROLLED diabetes because high glucose
level in the blood will cause delayed wound healing and
immunocompromise problem. Controlled diabetic patient should
have no problem in healing as their glucose level is kept
in check (70-111).
What are the pre-op medications
to be prescribed prior to undergo the sinus lift procedure?
The following medication are prescribed by Dr. Bui, D.D.S.,
M.S., at the preop appointment prior to sinus lift procedure.
In summary, they are antibiotics, anti-inflammatory, analgesic,
and antihistamine. Other operator may choose a different brand
of medication but the therapeutic actions should be the same.
- Antibiotics: Amoxicillin 500mg, taken i tab three
times a day for seven days, starting one day before surgery.
In the event of patient allergic to penicillin, clindamycin
300mg is used, with i tab taken four times a day for ten
- Analgesic: Darvocet N-100, taken i tab every 6 hrs
for pain, starting one hour before surgery. Other medications
may be prescribed are Lortab, and Vicodin. Lodine 400mg
can be prescribed if the patient does not prefer narcotic
- Anti-inflammatory: Dexamethasone 1.5 mg, 9mg the first
morning of surgery, 6mg the next morning, and 3 mg the third
day. The total dosage is 18mg for three days. In the event
that the tab dosage is .74mg, the number of tab is adjusted
to equal to the amount preferred.
- Antihistamine: Claritin 10mg, i tab daily for 10 days.
What are other effects we found
in lifting the sinus membrane?
First of all, the lifting of sinus membrane
will improve the bone height to favorably placing endosteal
implant. Secondly, in many case, it restore the floor of the
sinus to the normal physiologic level before the tooth is
lost. Moreover, in the people with prolonged tooth loss and
severe pneumotization of sinus, he or she may have suffered
poor drainage problem. These patients complaint that when
they lie down, the excessive drainage occurs. This contributes
to the halitosis, bad taste in the mouth, and in extreme case,
soft tissue polypses occur in the sinus cavity due to prolonged
irritation of sinus membrane leading to granulomatous tissue
formation. Many of our patient expressed that they breath
better after the sinus lift and the drainage problem is much
improved. The explanation for the improvement of drainage
is the relocation of the floor of sinus to the level close
to the ostium where the drainage occurs.
What happen if the sinus membrane
is perforated during the sinus lift?
The sinus membrane is a very thin membrane (similar to
our skin when it peels after sun burn) therefore perforation
may happen during the surgery. If it does happen, the surgery
should be closed up and reentered in 2-3months. It happened
to me once before, and I used Attribsorb membrane to close
the communication (the term described there is a hole connecting
the sinus cavity to the oral cavity) and also graft the bone
width prior to flap closure. Attribsorb is a flowable polymeric
barrier that composed of poly (DL-lactide)(PLA) dissolved
in N-methyl-2-pyrrolidone(NMP). It isolated the regenerative
site fom the adjacent gingival connective tissue and epithelium,
since the site needed to be reentered to place the implant.
Below is the case of sinus perforation that I discussed above.
Instead of just close up and wait, I opt to graft the adjacent
site and augmented the bone width. It never hurts to have
more bone width because increasing implant width can be placed
and that means increase the surface area of osseointegration.
From top to bottom: initial photo to show
the molar implant site (lack bone height) and the premolar
implant site(lack bone width); incision; flap reflect to show
narrow bone width on the premolar site; window prepare for
sinus lift; perforation of sinus window (membrane tear);
Adjacent column from top to bottom: flow
attrisorb to close the sinus window tear; perforate the cortical
bone with small bur on the implant site with narrow bone width;
place graft on the site and on the sinus window; flow another
layer of attrisorb curved up to the top of the ridge; photo
shows the radioopaque when membrane is hydrated and hardened;
top view to show ridge being augmented; flap released and
sutured with Goretex suture.
On the right hand column is an example of a
sinus lift procedure. As we have shown this is the case of
SA4. Nowaday experienced practioner does not want to place
implant immediately after extraction due to the phenomena
called "hot site", of which the osteoclastic action
and the residual infection in the area may lead to implant
failure. I used the mixture of biogran synthetic bonegraft
and demineralized freezed dried bone allograft (DFDBA) as
the graft material. Biogran is known for its hemostatic, osteoinductive,
and osteoconductive property. In many other cases, I may substitute
DFDBA with Bio-Oss bovine bone graft material. The principle
of guided bone regeneration is followed with the use of Ossix
resorbable collagen membrane (please select Guided
Bone Regeneration under services menu). Primary closure
achieved with flap released and coronally placed and sutured
with e-PTFE suture(Goretex). As seen in the comparison picture
below, we have augmented the subantral bone height from 4mm
to 15mm, which is enough to height to place a 13mm length
We offer payment plan with a low monthly payment and
if paid in full in the time specified, you will not have to
pay any interest. For any question, please do not hesitate
to call our office at 281-579-6066.
For full presentation of this case
done in Flash, please browse our porfolio section, under "Implant
Dentistry, Sinus Lift"