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Ogundipe et al. Iliac-bone graft reconstruction for benign mandibular pathology

citing the risk of micro-movement in non rigid by saliva, grafts are still able to perform well and
immobilization jeopardizing the viability of the graft, [25] survive in contaminated environments if rigid fixation
Although a number of the studies in this review is achieved. The high failure rate encountered by
employed rigid fixation of the graft with the use of earlier authors was largely blamed on contamination
plates and the authors claiming it as one of the main with saliva and subsequently led to the popularity of
factors for graft success. Few of the studies due delayed reconstruction to allow for use of extra-oral
to non-affordability of plates by patients employed route. This view is now being challenged by recent
the use of stainless steel wires for immobilization research and factors other than saliva contamination
with good outcomes even in long defect spans. [26] including research design of those earlier work are
However Olusanya et al. [19] employing use of wires being suggested to be responsible for the high failure
for immobilization reported progressive and significant rate noted in earlier works. [23] Other works in the
deviation and resorption in the central region with literature have also reported good outcome of grafts in
alteration in the initial aesthetic contour obtained contaminated environment when good immobilization
during a one year review period. This complication was ensured. [29] This view is supported by the results in
was absent in their patients that had reconstruction of the present review in which majority of the procedures
lateral defect. [19] On the contrary, Agrawal et al. and that initially presented with signs of infection eventually
[3]
Futran et al. [27] employing rigid plate fixation reported survived, with only few resulting in graft loss from the
progressive improvement in aesthetics with no report uncontrolled infection. It has also been argued that
of gross resorption noted. Okoturo [28] did not employ several intra-oral bone grafting procedures are carried
NVIBG for central defect (defect spanning between out with saliva contamination and most times without
33 and 43 i.e. C classification), the only two graft water tight closure including bone grafting procedures
failure were; one that had anterior component with the in implantology and periodontology with low failure
lateral component (excluding the condyle) (LC) and rates recorded. [23] As opined by Schlieve et al., [23]
another one that had anterior component with hemi- bone grafting in the presence of contamination is
mandibulectomy component (HC) claiming that non possible and this brings to question the fear of oral
vascular grafts do not perform well in this region and contamination during grafting procedures.
should be reconstructed with a flap.
Several published literature have reported significant
Compressive, tensile and torsional forces are present association between length of defect and graft failure. [24]
in the symphyseal part of the mandible which places Different authors have cited different lengths at which
significant stress on any construct placed in this use of non vascularized bone is significantly associated
region. These forces may exert excessive pressure on with complication. Pogrel et al. [14] cited a graft length of
the graft which may lead to rapid resorption and even 9 cm, more recent work have cited even shorter lengths
loss of the graft. Rigid reconstruction plate may help of between 5-6 cm suggesting that NVBG should only
to shield the graft from these forces and may explain be employed in defect size less than this cut-off. [25,31,32]
the progressive significant resorption noted in patients In the present review, Agrawal et al. also noted
[3]
where wire was used for graft immobilization as significant association between length of defect and
against those with plate immobilization in the central complication. They reported a mean defect length of 9.0
mandibular region. in those with complication compared with 7.0 in those
without complication. On the contrary, another study
[3]
A number of authors favor extra oral approach during in the present review found no significant association
the procedure of reconstruction with non vascularized between defect size and complication. [23] Although the
graft predicating their decision on avoidance of defect size in their series ranged between 3-10 cm
contamination of graft site with saliva leading to which is much outside the cut off of 5-6 cm suggested
infection and high failure rate. by earlier authors, no complication was associated with
length of defect. [23] Obiechina et al. [26] also reported
Majority of the authors in this review employed a no significant association between graft length and
combined intra and extra-oral approach. [6,19,26,28,29] graft failure. Part of their series involved grafting the
However, Schlieve et al. [23] and Shirani et al. [30] hemi-mandible spanning the symphysis to the ramus,
employed transoral approach with no record of graft only one graft failure lost to infection was recorded
loss among all their study population. Adequate although it was not stated whether it was one of the
(water tight, tension free) wound closure as well long span grafts. [26] Some authors have suggested that
as method of fixation was cited as important factors intra-oral approach alone resulted in better outcome
that contributed to the success. They claimed that of grafting because there was less disruption of soft
despite the potential risk of contamination of the graft tissue/periosteal envelope as well as less disruption of
Plastic and Aesthetic Research ¦ Volume 4 ¦ August 29, 2017 141