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Fariña et al. Skeletal anchorage for rigid external distractor

INTRODUCTION METHODS

Solving cases of severe maxillary hypoplasia has The study was a non-controlled, prospective study
always been a challenge for oral and maxillofacial involving 9 patients, 3 female and 6 male (9 to 24
surgeons. [1,2] Molina and Ortiz-Monasterio proposed years old; mean age 17.5 ± 5.4 years), selected from
[3]
a gradual advancement of the maxilla using a facemask the Department of Oral and Maxillofacial Surgery at
for elastic orthodontic traction or distraction. However, Hospital del Salvador between April 2007 and January
an adequate maxillary advancement in cases of 2015. Inclusion criteria were patients diagnosed with
severe hypoplasia was not achieved. Besides, the severe midface hypoplasia aged 5 years or older (to
forces applied could not be controlled and ulcers allow proper post distraction oclusal stability and an
in the chin and forehead were created. Polley and adequate teeth interdigitation shown in the hand-
[4]
Figueroa [1,5] also used elastic distraction with facemask articulated models).
and had similar findings, reporting insufficient maxillary
advancement (4 to 6 mm on average) with under- Preoperative assessment included clinical digital
corrected residual inverted anterior bite. photography, articulated models and three-dimensional
studies to plan a surgical treatment objective (STO).
In 1997, some authors proposed the use of the
rigid external distraction device I (RED I) [4-6] in order Distraction osteogenesis of the midface was performed
to overcome these shortcomings. The device was using SARED by means of the rigid external distraction
anchored to the skull and the denture in order to device (RED, Cibei Medical Treatment Appliance
distract facial bones. The use of the RED I became Co. Ltd., Ningbo, China). Depending on the STO a
[7]
an excellent treatment strategy, because it allowed Le Fort I or III osteotomy was done. When a Le Fort
precise and controlled distraction osteogenesis of III osteotomy (n = 6) was performed, the RED was
the maxilla. [8,9] Additionally, results were stable and anchored bilaterally with percutaneous wires to the
predictable. [10] Later, the RED II was introduced to infraorbital rims and the pyriform apertures (gauge
improve the vector control by means of an additional of 0.4 or 0.5 mm of stainless steel wire). When a Le
anchorage to the zygomatic bone plate. All of these Fort I osteotomy (n = 3) was performed, the RED was
attributes make the use of RED I and II an excellent anchored bilaterally with percutaneous wires to the
treatment alternative for patients with severe maxillary pyriform apertures only. In both cases the use of plates
hypoplasia. or screws were unnecessary, as the percutaneous wire
osteosynthesis was fixed directly to the bone.
RED I and II use a custom-made intraoral orthodontic
splint anchored to the first permanent molars or All patients were operated on by one surgeon.
[1]
second temporary molars to generate the maxilla
pulling force. The splint is made using cast models Surgical procedure
and 0.050 or 0.045 mm stainless steel wires. A wire
emerges from the splint up to the height of the nostril All surgeries were performed in an operating room,
floor, which generally coincides with the maxilla’s under general anaesthesia, using orotracheal
centre of rotation. intubation. Through a maxillary vestibular approach,
a Le Fort I (n = 3) or III (n = 6) osteotomy was
Despite the many advantages offered by the RED I and performed using a reciprocating or piezoelectric saw.
II, both devices have some disadvantages. The need In patients who underwent a Le Fort III osteotomy a
for teeth to anchor the device is one of them. [11] Dental transconjuctival approach was also utilised. A nasal
anchoring results in patient discomfort and interferes septum osteotomy and pterygomaxillary disjunction
with the normal functions of the oral cavity, i.e. eating, were performed subsequently.
speaking and performing proper oral hygiene. [12] On
the other hand, teeth act as an intermediary between A cylindrical burr was used to perforate below the
the RED and the bone to be distracted, impeding direct pyriform apertures. A 0.40-mm stainless steel wire was
force to be applied to the bone. [11] passed through the apertures to the floor of the nasal
cavity. A 14-G cannula was used to move the wire
The aim of this article is to propose an alternative to percutaneously towards the skin along the nasolabial
the dental anchorage used when distracting with RED fold.
I and II. We suggest the use of a skeletal anchorage
with a gauge of 0.4 or 0.5 mm of stainless steel wire, Patients who underwent a Le Fort III osteotomy also
that we called skeletal anchorage for the rigid external underwent upper skeletal anchorage. An aperture was
device (SARED). opened with a cylindrical burr alongside the mid lateral

Plastic and Aesthetic Research ¦ Volume 4 ¦ September 05, 2017 145