Firdaus Hariri

Alveolar distraction osteogenesis for oral rehabilitation in reconstructed jaws.

Purpose of reviewTo present a literature review of alveolar distraction osteogenesis (ADO) for reconstructed jaws, with emphasis on indications, critical surgical factors, protocols and complications for oral rehabilitation of reconstructed jaws. Recent findingsThe defects in jaw result mostly from malignancy, benign tumor or gunshot injury. Jaw reconstructions were performed mostly by vascularized fibula graft. Alveolar distraction was primarily indicated to correct vertical discrepancy between the reconstructed region and residual ridge in order to achieve adequate height of the transplanted bone prior to implant placement. The vertical bone height gained ranged from 6 to 15 mm. The most common complications reported were infections and distractor malalignment. SummaryThis review reveals few numbers of case series on this topic. However, ADO in reconstructed jaws can produce consistent evidence of bone regeneration, with stable augmentation results clinically, histologically and radiographically, thus making it a predictable surgical procedure prior to oral implant rehabilitation.

Alveolar distraction osteogenesis for dental implant rehabilitation following fibular reconstruction: a case series

OBJECTIVE Alveolar distraction osteogenesis (ADO), a novel bone augmentation technique, is gaining acceptance in restoring the vertical bone discrepancy between the transplanted graft and the residual alveolar bone after mandibular reconstruction. This case series presents the outcomes of ADO in fibula-reconstructed mandibles rehabilitated with dental implants, with an emphasis on clinical indications, surgical protocol, clinical outcomes, histologic evidence, and complications. MATERIALS AND METHODS Five patients underwent fibula distraction procedures after undergoing mandibular reconstruction with a vascularized fibula bone graft. The indication for the application of ADO was for the correction of the vertical discrepancy between the top of the reconstructed fibula and the adjacent alveolar crest to achieve adequate vertical bone height before implant placement. RESULTS The mean vertical bone height achieved was 13.58 mm. Twenty-two dental implants were placed in 5 patients. All patients were rehabilitated with implant-supported prostheses. Bone biopsies showed the distracted area was filled with newly formed, bony trabeculae between the transported fibula and the basal segments. The most common complication was transient infection around the distractor rod. CONCLUSIONS ADO can be performed on fibula-reconstructed mandibles to achieve the restoration of alveolar height, which then can be rehabilitated with dental implant-supported prostheses. The procedure has a minor risk of infection associated with the distractor rod, which does not compromise the bone regeneration from distraction. Patients with mandibles reconstructed with fibulas can attain dental implant rehabilitation with ADO, achieving good esthetic and occlusal outcomes.

A Rare Orbital Complication of Eye Exodeviation With Limited Abduction During Monobloc Le Fort III Distraction Osteogenesis

Monobloc Le Fort III distraction osteogenesis allows superior skeletal advancement in treating severe syndromic craniosynostosis. We report a rare orbital complication in a 3-year-old boy with Crouzon syndrome who developed right-eye exodeviation with limited abduction during the intradistraction period following this surgery. Images from a computed tomography scan confirmed direct impingement of the distracted right lateral orbital wall to the lateral rectus muscle. The impingement was surgically relieved via lateral orbital wall osteotomy. Ten months postdistraction, a review showed normal eye movement. A lateral orbital osteotomy cut for a monobloc Le Fort III distraction should be designed near the rim to prevent this complication.

Characteristics and Young's Modulus of Collagen Fibrils from Expanded Skin Using Anisotropic Controlled Rate Self-Inflating Tissue Expander

Mechanical properties of expanded skin tissue are different from normal skin, which is dependent mainly on the structural and functional integrity of dermal collagen fibrils. In the present study, mechanical properties and surface topography of both expanded and nonexpanded skin collagen fibrils were evaluated. Anisotropic controlled rate self-inflating tissue expanders were placed beneath the skin of sheeps forelimbs. The tissue expanders gradually increased in height and reached equilibrium in 2 weeks. They were left in situ for another 2 weeks before explantation. Expanded and normal skin samples were surgically harvested from the sheep (n = 5). Youngs modulus and surface topography of collagen fibrils were measured using an atomic force microscope. A surface topographic scan showed organized hierarchical structural levels: collagen molecules, fibrils and fibers. No significant difference was detected for the D-banding pattern: 63.5 ± 2.6 nm (normal skin) and 63.7 ± 2.7 nm (expanded skin). Fibrils from expanded tissues consisted of loosely packed collagen fibrils and the width of the fibrils was significantly narrower compared to those from normal skin: 153.9 ± 25.3 and 106.7 ± 28.5 nm, respectively. Youngs modulus of the collagen fibrils in the expanded and normal skin was not statistically significant: 46.5 ± 19.4 and 35.2 ± 27.0 MPa, respectively. In conclusion, the anisotropic controlled rate self-inflating tissue expander produced a loosely packed collagen network and the fibrils exhibited similar D-banding characteristics as the control group in a sheep model. However, the fibrils from the expanded skin were significantly narrower. The stiffness of the fibrils from the expanded skin was higher but it was not statistically different.

A Novel Technique Using Customized Headgear for Fixation of Rigid External Distraction Device in an Infant With Crouzon Syndrome.

AbstractRigid external distraction device is often indicated for superior midfacial advancement in pediatric syndromic craniosynostosis patients. Even though the technique is proven reliable to treat the functional issues related to the craniofacial deformity, major complications associated with its fixation, such as intracranial pin perforation and migration have been reported. We report a novel technique of using a customized headgear to prevent intracranial pin perforation over a very thin temporal bone region in an 8-month-old infant with Crouzon syndrome who underwent monobloc Le Fort III distraction osteogenesis using a combination of bilateral internal and a rigid external distraction device. The customized headgear provides a protective platform at the temporal region thus preventing intracranial pin perforation and allows stable fixation during the early phase of consolidation period to prevent central component relapse. The headgear can be used short term when rigid external distractor is indicated in infant patient but requires close monitoring because of risks of skin necrosis and temporal region indentation.

Monobloc Le Fort III distraction osteogenesis for correction of severe fronto-orbital and midface hypoplasia in pediatric Crouzon syndrome

In severe syndromic craniosynostosis, distraction osteogenesis (DO) provides superior segmental advancement and allows progressive clinical monitoring to ensure that adequate skeletal expansion is achieved. We report two cases of Crouzon syndrome involving a 3-year-old boy and a 4-year-old girl, who were both treated with monobloc Le Fort III DO using a combination of external and internal distraction devices (Synthes, Oberdorf, Switzerland) to treat severe orbital proptosis and obstructed nasopharyngeal airway secondary to severe hypoplastic craniofacial skeletal components. Their skeletal segments were advanced in daily increments by 27 mm and 23 mm, respectively. Results at 18 months postoperatively showed successful outcomes, as evidenced by adequate eye protection, tracheostomy tube decannulation following objective evidence of patent nasopharyngeal airway, and acceptable facial appearance. Monobloc Le Fort III DO using a combination of external and internal devices produces favorable functional and clinical outcomes for the treatment of severe orbital and airway discrepancy in Crouzon syndrome.

Crouzon syndrome: Genetic and intervention review

Crouzon syndrome exhibits considerable phenotypic heterogeneity, in the aetiology of which genetics play an important role. FGFR2 mediates extracellular signals into cells and the mutations in the FGFR2 gene cause this syndrome occurrence. Activated FGFs/FGFR2 signaling disrupts the balance of differentiation, cell proliferation, and apoptosis via its downstream signal pathways. However, very little is known about the cellular and molecular factors leading to severity of this phenotype. Revealing the molecular pathology of craniosynostosis will be a great value for genetic counselling, diagnosis, prognosis and early intervention programs. This mini-review summarizes the fundamental and recent scientific literature on genetic disorder of Crouzon syndrome and presents a graduated strategy for the genetic approach, diagnosis and the management of this complex craniofacial defect.

Tongue necrosis secondary to mucormycosis in a diabetic patient: A first case report in Malaysia

Mucormycosis is a rare fungal infection and high mortality that commonly affects patients with the weakened immune system. We present an unusual case of tongue necrosis probably due to the healthcare-associated mucormycosis (HCM) in a diabetic patient. Although cannot be proved with certainty, we surmise that intubation as a risk factor in our case. The diagnosis was confirmed by histopathological examination (HPE) of the necrotic tissue specimen. The patient was responded well to lipid complex amphotericin B (250mg) regime after surgery. Subsequent follow up revealed that no signs of recurrence. Early, recognition, diagnosis, prompt treatment and awareness among clinician are representing the most effective way of managing the disease.