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These materials are aimed to replace the abnormal soft
tissue and to restore volume of the orbit, to finally restore
ocular function as well as aesthetic appearance. They can
also be divided into many autologous grafts, allografts,
xenografts and alloplastic grafts.

As the “gold standard” of craniofacial reconstruction,
autologous bone graft should be the first to be used in this
Figure 3: Example of polyethylene for reconstruction of internal orbital
defect. (A) Shaped and sized polyethylene; (B) material in the orbit with process. However, the rigidity of bone (especially cranium)
bone screwed intaoperatively. Adpated from Ellis and Messo [27] is relative to the increase of intraocular pressure that
might influence the movement of eye and the optic nerve.
Furthermore, the donor site morbidity is inevitable.
Silicone oil was one of the first injectable materials placed
into the orbit for volume augmentation. Since 1960s, silicone
oil has been used for volume augmentation. It’s cheap
[42]
but its outcome is not satisfactory and it needs multiple
injections. Many authors have reported complications like
extrusion, immigration of implants and infections. [43]

Autologous fat graft (either as free fat or dermal fat graft)
has been used since the end of the 19th century to handle
various soft-tissue defects. Lipofilling, also known as
autologous fat transplantion, has been investigated for
a long time, especially as a natural implant for aesthetic
and reconstructive purposes. Neuber first used fat
[44]
Figure 4: Minimally invasive autologous fat injection: atraumatic suction, autografting to correct facial defects in 1893. He reported
furification, and reinjection in the orbit using a cannula. Adapted from
Cervelli et al. [50] a 20% to 90% graft absorption rate, so these defects require
multiple injections to obtain a satisfactory target. In 1970s,
available for craniofacial surgery since the 1990s. As opposed dermal fat transplants were used to fill the orbit. Similarly
to porous polyethylene, HA is more fragile, more expensive, to other autologous implants, they have outstanding high
and not as easily shaped intraoperatively. HA appears biocompatibility with minimal infection rate. However, the
[34]
to have a higher risk of postoperative enophthalmos than risk of operation and the donor site morbidity still exist.
medpor. Bioactive glasses (BAGs) are synthetic blocks or
[35]
granules that bond chemically to bone. Despite the fact that In 1980s, collagens injectable became more popular.
BAGs are of brittle nature and hard to mould and shape, High resorption grade of non cross-linked collagen gives
they are osteoinductive and osteoconductive. [36-38] They unsatisfactory results. The use of cross-linked collagen
can prompt the repair of bone with minimal foreign body (Zyplast) in the orbital region has a documented risk of
reaction, infection, extrusion and resorption. [39] blood vessels occlusion, which can lead to a severe visual
damage. [45]
COMPOSITES
In the last decade, Hunter and Baker described the use of
[46]
Composites are an interesting attempt to utilize the autologous fat in the orbit for the correction of posttraumatic
advantages of one selected material while reducing its enophthalmos. The outcome was not good for most of
disadvantages with another material. An example is their patients and needed a second injection. Coleman [47,48]
the titanium-reinforced PE. Titanium mesh offers the reported his technique, defined as atraumatic liposuction
advantages of high strength and stability, easy contouring, with injection of purified fat, for fat transfer: harvesting,
and radiopacity in postoperative imaging, while PE implants purification by centrifugation, and injection. This technique
have a smooth surface allowing free movement of orbital indeed improved the survival rate of fat. Hardy et al.
[49]
tissue. [40] obtained good results in a retrospective study of 12 patients
with anophthalmic and enophthalmos; a further injection
SOFT TISSUE FILLING MATERIALS was necessary in only 1 case. Autologous fat seems to be the
ideal filling material for soft tissue defect. Autologous fat is
As mentioned above, repairing only the fracture is not an ideal filler because of its excellent biocompatibility as a
suffcient. Even if repaired perfectly, many patients may suffer living graft, which is easily harvested and incorporated into
from late sequelae such as enophthalmos due to soft tissue the surrounding tissues with no hypersensitivity potential
abnormality within the orbit. It’s claimed that alterations and minimal chance of infection. It is readily available in
like atrophy or herniation of soft tissue have a decisive part large quantities at low cost, and grafted fat gives a natural
[41]
in the enophthalmos after orbital reconstruction. Thus, consistency with excellent volume augmentation. It is
we must act to prevent late sequelae by using soft tissue potentially permanent and the regenerative ability of fat is
filling materials. believed to improve the overlying skin quality. Autologous fat
Plast Aesthet Res || Vol 3 || Mar 23, 2016 89