Harvesting of bone from the iliac cres /certified fixed orthodontic courses by Indian dental academy

Harvesting of bone from the iliac crest –
Comparison of the anterior and posterior sites.

INDIAN DENTAL ACADEMY
Leader in continuing dental education
www.indiandentalacademy.com

For more than 4 decades the iliac crest has been the
accepted place to get bone for augmentation procedures.
Main indications in OMFS are osteoplasty in patients
with cleft lip and palate, augmentation of bony defects after
operations for tumours or large cysts and augmentation in
preprosthetic surgery for severe cases of atrophy of the
alveolar crest from early loss of teeth or aging process.
Main advantages of iliac crest :
- Easy accessibility.
- Possibility of harvesting large amounts of bone.

- Ability to close the wound primarily.
Anterior iliac crest is more accessible as a donor region
and bicortical grafts can be taken.
Two disadvantages :
- Bicortical bone layers between the internal and
external cortices below the anterior iliac crest are as thin as
a blade, often making it difficult to obtain a sufficient bone
volume.
- Risk of fracturing anterior iliac spine, which results in a
long lasting obstacle to walking and climbing stairs.

Bicortical width of the bone layer beneath the posterior
iliac crest does not shrink this region, it always offers
enough cortical and cancellous bone for augmentation
even in cases of extreme alveolar atrophy or for the
reconstruction of large bony defects.
Less morbidity - Irregularities of gait do not occur, the
patient can be mobilized earlier and has less pain.
Main disadvantage – Necessity to turn the patient in the
course of the operation, which lengthens the operating
time.

This prospective, non – randomised study
was conducted in 1998 and compares the
amount of bone harvested, the operating
time and the postoperative morbidity.


PATIENTS AND METHODS :
118 patients were operated on 127 occasions in 1998.
In 81 cases the bone was harvested from anterior iliac
crest, in 46 from the posterior.
There were 65 men and 53 women.
Mean age was 44 years. ( Range : 8 – 80 ).
Indications for harvesting :
- Bony defects after resection of tumours ( n = 40 ).
- Extreme atrophy of the upper and lower alveolar
crests ( n=33 ).

- Cleft lip or palate defects ( n=25 ).
- Defects after removal of large cysts ( n=17 ).
- Posttraumatic defects ( n=12).
Anterior iliac crest was chosen in all patients with cleft
lip or palate and in patients with large cystic lesions. (Only
cancellous bone).
This was also preferred if only one quadrant of the jaws
had to be augmented and for sinus lift operation in patients
with highly atrophic alveolar processes.


For defects after resection of tumours or trauma the
anterior iliac site was used, if the defects could be
reconstructed by a maximum of 2 or 3 corticocancellous
bone strips about 40 - 50 mm long and 10 – 12 mm wide.
Antibiotic prophylaxis ( Penicillin 10 million units IV)
started the evening before operation and was continued
twice a day until the evening of 2nd post op day.
Steroid ( Prednisalone ) given 250mg morning and
evening on the day of operation and 125mg morning and
evening on 1st post op day.

Criteria for exclusion :
 Previous operations in this area.
 Systemic bony or neurological diseases.
 Long standing treatment with steroids,
immunosuppression drugs.
 Chemotherapy in the previous 2 months.
 Drug misuse in the previous 3 months.


All patients operated under general anaesthesia.
For harvesting bone from the anterior iliac crest the
patient lies supine.
The pelvis is raised about 30 degrees.
Skin over the iliac crest is put under stretch by placing a
fist above the iliac crest and pushing the abdominal wall
medially.
Skin incision is about 50mm long, starts about 20mm
behind the anterior iliac spine and runs parallel to the
crest.

After relaxing the skin the incision line finally lies about
20mm lateral to the crest, avoiding mechanical irritation of
the scar by tight clothes.
Blunt dissection of the subcutaneous tissues until the
periosteum of the crest is found.
Periosteum is incised and periosteal layer with the iliac
muscle dissected bluntly medially.
Iliac fossa is dissected to a depth of about 80mm.
An oscillating saw is used to cut parallel strips of
monocortical bone from the inner table of pelvic bone at
right angles to the line of iliac crest.

Strips are about 15mm wide.
Cancellous bone is then harvested using a sharp spoon.
Area of defect is rinsed and a collagenous tampon is
used to stop bleeding.
Wound is closed in layers and pressure bandage is
applied.
In adolescents only anterior approach was used. The
cartilage covering the iliac crest is incised after the fashion
of a double door. After harvesting the bone the cartilage
cover is replaced and sutured with absorbable sutures.

Anterior iliac crest showing exposure of the superior

crest.


Posterior incision is made with the patient prone.
Incision is about 80mm long, follows a diagonal line
from a cranial and medial position below and laterally and
crosses the posterior iliac crest.
It is the safe way to protect the gluteal branches of
posterior cutaneous nerves.
After blunt dissection of the gluteal muscles the external
bony wall of the posterior iliac crest is exposed.
The external cortical bone is cut and harvested in the
same way as anterior iliac crest and wound is closed
similarly.

Time taken for positioning either supine or prone
was recorded.
All patients required bed rest for first 24 hrs and were
then mobilized on 2nd post op day.
Disturbances of gait – including limp, unsteadiness
and deviation were documented on days 14 and 28 after
operation.
On 3rd post op day patients were asked to estimate
pain from where bone had been harvested using Visual
Analogue Scale from 0 to 10.

Exposure of the posterior site of harvesting in the
iliac crest.


RESULTS :
Mean volume of 15 cu.cm ( range 9 – 25.5 ) was
harvested from iliac crest , which included monocortical
bone chips, bicortical bone chips and bone taken with
punch needle.
Mean volume harvested :
- Anterior iliac crest – 9 cu.cm ( range 5 – 12 )
( n=81 ).
- Posterior iliac crest – 25.5 cu.cm ( range 17 – 29 )

(n= 46 ).

Mean operating time :
- AIC – 35 min ( range 22 – 48 ).
- PIC – 40 min (range 32 – 55 ).
These times does not include preparation of the area
around the head and neck and for changing the position
of the patient for harvesting bone from the PIC.
This maneuver took an additional mean time of 20
min.


DISCUSSION :
Overall rate of complication was 12 % and the
anterior approach to the ilium caused considerably
more problems than posterior approach.
Main advantage of PIC region is that up to 3 times
more cancellous bone can be obtained for
transplantation.
Disadvantages of a slightly prolonged operation time,
the necessity to change the position of the patient and
the restriction to harvest only monocortical bone grafts
seem to be less important.

In adult patients, particularly in those cases, in which
large volumes of bone are required, posterior approach is
preferred.
Patients have significantly less pain and fewer
irregularities of gait.
In patients with cleft lip or palate the anterior iliac crest
should be used as the amount of bone needed is usually
not as great as in operations for augmentation of atrophic
alveolar processes.


Leader in continuing dental education


Harvesting of bone from the iliac cres /certified fixed orthodontic courses by Indian dental academy

Recommended

Recommended

More Related Content

What's hot

What's hot (20)

Similar to Harvesting of bone from the iliac cres /certified fixed orthodontic courses by Indian dental academy

Similar to Harvesting of bone from the iliac cres /certified fixed orthodontic courses by Indian dental academy (20)

More from Indian dental academy

More from Indian dental academy (20)

Recently uploaded

Recently uploaded (20)

Harvesting of bone from the iliac cres /certified fixed orthodontic courses by Indian dental academy