TYPES OF GRAFTS:
Osseointegrated
implants can be combined with the following
types of graft: inlay, saddle, veneer, onlay (partial or full arch), and maxillary sinus grafts. (Triplett & Schow, 1996)
The mucoperiosteal flap should be designed to adequately expose the underlying residual ridge, maintain a broad base for vascular support, and allow tension-free primary closure. A midcrestal incision is usually preferred because it maximizes the vascularity to the margins of the mucoperiosteal flaps and minimizes ischemia created by the vasculature traversing dense
,
keratinized tissue at the crest of the ridge. Labial vertical releasing incisions are made as needed to improve access. All grafts must be well adapted to
the
recipient site with no or minimal space
betveen
between
graft and residual bone. Hence, usually graft shaping and adaptation is unavoidable.
The g
G
raft
is
positioned to its best adaptation to the underlying alveolus. A good fixation with titanium screws must be achieved to prevent
the
graft movement. Any movement of the graft increase
s
the chance of soft tissues ingrowth between the graft and
the
recipient site,
and
thus
the
failure of the graft is likely. All voids or defects should be filled with particulate cancellous bone and marrow to provide good contour and eliminate dead space. A primary, tension-free closure must be achieved to prevent wound breakdown and graft exposure. A barrier membrane and filler graft may be used, if desired.
Inlay Grafts
Small osseous defects at the alveolar crest can be inlaid with an autologous graft to restore the contour and volume of bone necessary to place
an
the
implant and allow for a proper emergence profile.
The defect is usually exposed through a crestal incision that
is
extended around the necks of one or two adjacent teeth on either side of the defect. A vertical releasing incision is made if necessary. A barrier membrane may be used to protect these areas during healing.
Saddle Graft
Indicated where both horizontal and vertical ridge augmentation
[S1]
, this type of graft is also of considerable value.
A
a
utogenous bone stabilized with rigid fixation to restore anatomic height and width is an excellent solution to this problem. A saddle of bone is obtained from the anterior-inferior border of the mandible (ipsilateral site) and secured in position from the buccal or crestal aspect with 1.5
mm titanium screws with a minimum of 2 screws to achieve stable graft fixation.
Veneer Graft
A veneer graft is preferred where there is only
a
horizontal bone defect
o
f
less than 4
mm.
T
Onlay Graft
The design of onlay grafts can be segmental or arch in shape.
Both the height and width of an atrophic ridge can be achieved with onlay grafts.
Following
I
i
ndications include
the following
[S2]
: inadequate residual alveolar ridge height and width to support a functional prosthesis, contour defects that compromise implant support, function, or
a
esthetics, and segmental alveolar bone loss.
-
Procedures aimed at increasing the volume of attached mucosa (free soft tissue grafts, pedicle soft
tissue grafts, and surgical extension of the vestibulum) have been recommended in areas of movable
mucosa.
75,77,102111
[S3]
(Esposito, Hirsch, Lekholm, & Thomsen, 1999)
There was
It has also been
also
stated that cancellous grafts
are
more successful because of cortical plate (
Buchman 1999 Cancelous Bone stucture.pdf,
n.d.)
Results:
-
A p
P
ositive correlation outcome was found between age and missing teeth found in both groups A and B
in the
applied multiple regression analysis (SPSS)
Group A analysis for correlation between the patients age and number of teeth missing outcome:
|
|
|||
|
Patients age |
Number of Teeth |
||
|
Patients age |
Pearson Correlation |
1 |
.326 |
|
Sig. (2-tailed) |
.000 |
||
|
N |
120 |
111 |
|
|
Number of Teeth |
Pearson Correlation |
.326 |
1 |
|
Sig. (2-tailed) |
.000 |
||
|
N |
111 |
111 |
|
|
**. Correlation is significant at the 0.01 level (2-tailed). |
|||
Group B outcome:
|
|
|||
|
Patients age |
Number of Teeth |
||
|
Patients age |
Pearson Correlation |
1 |
.465 |
|
Sig. (2-tailed) |
.004 |
||
|
N |
41 |
37 |
|
|
Number of Teeth |
Pearson Correlation |
.465 |
1 |
|
Sig. (2-tailed) |
.004 |
||
|
N |
37 |
37 |
|
|
**. Correlation is significant at the 0.01 level (2-tailed). |
|||
-
A p
P
ositive correlation
was
found between age and bone volume harvested in Group A. However, the correlation in Group B was non
significant.
Group A multiple regression analysis output:
|
|
|||
|
Patients age |
Bone graft volume |
||
|
Patients age |
Pearson Correlation |
1 |
.244 |
|
Sig. (2-tailed) |
.007 |
||
|
N |
120 |
120 |
|
|
Bone graft volume |
Pearson Correlation |
.244 |
1 |
|
Sig. (2-tailed) |
.007 |
||
|
N |
120 |
120 |
|
|
**. Correlation is significant at the 0.01 level (2-tailed). |
|||
Group B SPSS multiple regression analysis output:
|
|
|||
|
Patients age |
Bone graft volume |
||
|
Patients age |
Pearson Correlation |
1 |
.203 |
|
Sig. (2-tailed) |
.203 |
||
|
N |
41 |
41 |
|
|
Bone graft volume |
Pearson Correlation |
.203 |
1 |
|
Sig. (2-tailed) |
.203 |
||
|
N |
41 |
41 |
|
-
The distribution for harvested overall bone volumes was found to be normal in both groups A and B and a significant correlation was found between
clinitian
clinician
A and
clinitian
clinician
B and their harvested bone volumes.
Distribution analysis output. Histogram:
Multiple regression analysis output for
Clinitian
Clinician
A
|
|
||||||
|
Model |
Sum of Squares |
df |
Mean Square |
F |
Sig. |
|
|
1 |
Regression |
9317266.326 |
1 |
9317266.326 |
31.994 |
.000 |
|
Residual |
42518278.360 |
146 |
291221.085 |
|||
|
Total |
51835544.685 |
147 |
||||
|
2 |
Regression |
16022829.759 |
2 |
8011414.879 |
32.437 |
.000 |
|
Residual |
35812714.927 |
145 |
246984.241 |
|||
|
Total |
51835544.685 |
147 |
||||
|
a. Dependent Variable: Bone graft volume |
||||||
|
b. Predictors: (Constant), Number of Teeth |
||||||
|
c. Predictors: (Constant), Number of Teeth, Procedure Performer |
||||||
-
Association between
a
patients gender and performed clinicians A an
d
s
B found to be not statistically significant applying SPSS multiple regression analysis.
The SPSS output for multiple regression analysis:
|
|
|||||
|
Procedure Performer |
N |
Mean |
Std. Deviation |
Std. Error Mean |
|
|
Patients age |
AP |
41 |
38.85 |
11.599 |
1.811 |
|
SG |
120 |
39.05 |
11.876 |
1.084 |
|
|
|
||||||
|
Cases |
||||||
|
Valid |
Missing |
Total |
||||
|
N |
Percent |
N |
Percent |
N |
Percent |
|
|
Procedure Performer * Patients Gender |
161 |
100.0% |
0 |
0.0% |
161 |
100.0% |
|
|
|
|
Patients Gender
Categories:
|
