Development of the 3D-cephalogram: a technical note.

INTRODUCTION: The authors developed the 3D-cephalogram via combination of 3D-CT and cephalometric analysis. METHODS: The 3D-cephalogram can directly express cephalometric data on the surface of skeletal structures in a manner similar to a conventional cephalogram. RESULTS: This analysis revealed complex facial asymmetries in particular, on either side of the mandible. Images displayed no geometric error due to magnification nor any overlap effect inherent in the conventional cephalogram. CONCLUSIONS: The 3D-cephalogram is helpful in instructing physicians, and patients themselves regarding pathological anatomy and treatment procedures.

Combined chondrocyte-copolymer implantation with slow release of basic fibroblast growth factor for tissue engineering an auricular cartilage construct.

Basic fibroblast growth factor (b-FGF) may have a role in tissue-engineered chondrogenesis. However, when applied in solution, b-FGF rapidly diffuses from the implant site. In another approach for tissue engineering, poly-lactide-based copolymers have shown promise as scaffolds for chondrocytes used to tissue engineer auricular cartilage in the shape of an ear. This study evaluated the effectiveness of b-FGF impregnated in gelatin microspheres to achieve slow growth factor release for augmenting the in vivo chondrogenic response. Whereas 125I-labeled b-FGF injected in solution showed rapid in vivo clearance from the injection site (only 3% residual after 24 h), when incorporated into gelatin microspheres, 44% and 18% of the b-FGF remained at 3 and 14 days, respectively. Canine chondrocytes were isolated and grown in vitro onto ear-shaped poly-lactide/caprolactone copolymers for 1 week, then implanted into the dorsal subcutaneous tissue of nude mice; implants contained b-FGF either in free solution or in gelatin microspheres. A third group underwent preinjection of b-FGF in gelatin microspheres 4 days before chondrocyte-copolymer implantation. The implants with b-FGF-incorporated microspheres showed the greatest chondrogenic characteristics at 5 and 10 weeks postoperatively: good shape and biomechanical trait retention, strong (histologic) metachromasia, rich vascularization of surrounding tissues, and increased gene expression for type II collagen (cartilage marker) and factor VIII-related antigen (vascular marker). In the case of implant site preadministration with b-FGF-impregnated microspheres, the implant architecture was not maintained as well, and reduced vascularization and metachromasia was also apparent. In conclusion, these findings indicate that a sustained release of b-FGF augments neovascularization and chondrogenesis in a tissue-engineered cartilage construct.

Scanning electron microscopic observations of 'fractured' biodegradable plates and screws.

BACKGROUND: We encountered two out of 100 cases in which implanted biodegradable plates and screws had fractured within 1 month postoperatively. MATERIAL: Failure of the material was confirmed through clinical symptoms, radiographs or CT findings. In addition, four specimens obtained from these two cases were examined with regard to their ultrastructure using scanning electron microscopy. RESULTS: Several principal patterns of the fractured surface were found: (1) gradual cracking, i.e. 'circular stair' and, (2) tortuous threads, i.e. a wavy line. It is conceivable that the material may not have been hit by major sudden forces but a disproportion between the thread configuration and the drilled hole may have led to screw loosening and torsion. Subsequently, the threads were deformed in a 'wavy' manner, finally leading to cracking and fracture of plates and screws. Fractures of plates and screws due to these instabilities are thought to be distinguishable from material resorption. CONCLUSION: In the application of biodegradable materials, more than two screws per single bone segment should be used as a principle of plate-fixation technique in order to avoid a stability-compromising situation, particularly in the stress-bearing areas of the maxillofacial region. Moreover, three-dimensional fixation using more than two plates is recommended in the facial skeleton e.g. zygomatic tripod. Intermaxillary fixation should also be considered to reinforce initial stability in stress-bearing areas.

Intracranial migration of fixation wires following correction of craniosynostosis in an infant.

BACKGROUND: In the craniofacial skeleton, osseous fixation techniques for stabilization include stainless steel wire, miniplates or bioresorbable plates; in some cases, stainless steel wires are still indicated. Most recently, several case reports have demonstrated that microplates or stainless steel wires migrate intracranially when used in the craniofacial skeleton in neonates. PATIENT: We present the case of a 7-year-old male who underwent treatment of brachycephaly at the age of 5 months. In this patient, internal migration of wires was observed. CONCLUSION: In our opinion, there is a difference between migration of wires and of plates in the growing cranium. Factors affecting the incidence of material migration in cranioplasty are believed to include (1) age, (2) site and (3) the material itself.

Orbital wall reconstruction with bone grafts from the outer cortex of the mandible.

AIM: The purpose of the study was to assess the efficacy of bone grafting from the mandibular outer cortex for reconstructing the orbital walls. MATERIAL AND METHODS: Bone grafting was performed in 75 patients. The site the transplants were harvested from were: A: mental region, B: area posterior to the mental foramen, C: ramus region. In order to obtain the appropriate curvature for the orbital floor, proper selection of the donor area is required. The bony defect size was confirmed pre-operatively from 3D-CT data. Bone, characteristically 2-3 mm thick, was harvested from each area and grafted into the blow-out fractures. RESULTS: Out of the 75 patients 13 cases underwent reconstruction using mandibular outer cortex bone from area A, 8 from area B, and 54 from area C. The maximum size available for harvest from area C was 7 x 4 cm; material from this area could also be used for the repair of both medial and inferior orbital wall defects if necessary. CONCLUSION: Bone harvest from the mandible affords several advantages including (1) ease of harvest, (2) ease of trimming, (3) appropriate size and curvature, (4) absence of functional disability, (5) no secondary deformity, (6) no visible scars, (7) post-operative immobilization not necessary, (8) absence of post-operative difficulties with respect to breathing and walking and (9) major complications are rare.

Retrograde dacryocystography (RDC) utilizing a round-tipped needle.

Because the application of conventional anterograde dacryocystography has been restricted in cases with an intact lacrimal punctum, the indications are rather limited. The authors developed a new method for retrograde dacryocystography (RDC) using a hand-made round-tipped needle inserted directly into the orifice of the nasolacrimal duct. A 60 mm long aluminum tube (3 mm in diameter) was used to prepare the round-tipped needle. The distal portion of the tube was bent to an angle of about 80 degrees. The tip was then coated with synthetic resin adhesive to make it round. Following the insertion of the round-tipped needle directly into the inferior meatus, the tip was moved back and forth to find the orifice without visual observation. The complete insertion of the tip of the needle into the nasolacrimal duct was recognized by a fixed sensation of the tip. Contrast medium was then injected, and PA radiography was carried out. In the present paper, the authors report the usefulness of RDC, which is applicable even in cases of injury or obstruction in the upper lacrimal system. In 16 of 20 patients, the quality of the RDC images was judged as excellent. RDC can be carried out within a few seconds after acquiring the technical skills, and is thought to be a useful method, especially in cases of upper lacrimal injury.

Bilateral parotid sialoadenitis with gonial hypertrophy.

Sialoadenitis is a non-inflammatory condition that affects mainly the parotid, and is characterised by bilateral, painless swelling, which is an appreciable problem in young women. A 28-year-old woman presented with parotid sialoadenitis with masseteric hypertrophy. She was treated by superficial parotidectomy and ostectomy of the mandibular angle and made an uncomplicated recovery.

Quantitative analysis of the reconstructed breast using a 3-dimensional laser light scanner.

Postoperative cosmesis of the reconstructed breast depends on the interrelation of shape, size (volume), and symmetry. In this study, reconstructed breasts were analyzed with 3-dimensional projections generated by laser light scanning. Fifty-one cases of breast reconstruction following mastectomy (16 cases of rectus abdominis flap, 15 cases of latissimus dorsi flap, and 20 cases of tissue expansion) were evaluated 6 months postoperatively. Shape, volume, and symmetry were quantitatively evaluated. Captured images of the normal breast were mirror-reversed and superimposed on images of the reconstructed breast. Differences in the generated Moire patterns were used to quantitatively compare breasts. The method was rapid, reproducible, and accurate in comparison to thermoplaster casts. It was found that rectus abdominis flaps applied following total mastectomy and latissimus dorsi flaps applied following partial mastectomy gave the best results for their relatively low degree of asymmetry. Application of tissue expansion led to greater asymmetry and poorer overall cosmesis. In conclusion, a 3-dimensional laser light scanning system makes it possible to quantitate the cosmetic outcome following breast reconstruction.