Dove tail osteotomy in distraction osteogenesis of costochondral bone grafts in the mandible: a new concept.

To correct the malocclusion and facial asymmetry in patients with Pruzansky type III hemifacial microsomia after autogenous costochondral grafting during early childhood (two male and three female patients with an average age of 17.8 years), the technique of distraction osteogenesis with a three-dimensional device was used. Because of the missing periosteum of the transplanted rib and its relatively small height compared with the horizontal mandible, a dovetail geometrical pattern osteotomy was introduced to increase the osteotomy surface area, which by itself could enhance the amount of fibrin filaments between 30% and 40% in the hematoma occurring during the initial distraction process. These fibrin filaments are biofunctional guiding structures for the development of the microcallus, followed by enhancement of the bone-healing capacity, which allows optimal bone regeneration. Between 20 and 27 days (mean = 21.5 days) after distraction, complete ossification was noted radiographically in all treated patients. Based on our histological animal studies and clinical investigations, dove tail osteotomy enhances the osteotomized surface area and offers protection to the tension-sensitive structures in the center of the distraction zone. It increases early bone formation and mineralization adjacent to the center zone in the distraction gap. Therefore, the dove tail geometrical pattern in combination with distraction osteogenesis of autologous costochondral grafts in the treatment of congenital Pruzansky type III mandibular hypoplasia is strongly recommended.

Experimental study of the frontal sinus development on Goettingen miniature pigs.

According to the literature, the development of the frontal sinus cavity is a result of the active immigration of cells from the ethmoidal complex into the os frontale. This migration theory is in contrast to the operative outcome of Apert's syndrome patients, after fronto-orbital advancement. When a fronto-orbital advancement at the age of a few months is performed in these patients while the frontal suture is yet closed, a sinus developed even the distance between nasal root and frontal bone bing up to 2 cm. In order to study the development of the frontal sinus, an animal study on 12 five-week-old infant Goettingen minipigs (GMP) was conducted, which did not have any clinical or histological signs of a frontal sinus development to investigate the development of the frontal sinus in "orthotopically" transplanted frontal bone with an open frontal suture. A comparison was made to a control group. The macro- and microscopical comparison with a control group revealed that the orthotopical transplants in the occipital bone developed epithelium-lined sinus, beginning from the thirty-fifth week. Based on these histomorphological results, a development scheme for the genesis of the sinus frontalis as a model were drawn.

Mandibula distraction osteogenesis for lengthening the mandibula to correct a malocclusion: a more than 70-year-old German concept in craniofacial surgery.

Bone distraction is still on the rise again since McCarthy et al. presented in their clinical investigation new osseous formation in the elongated area while performing the distraction of the mandible in 1992. But at the level of craniofacial skeleton, the initial description to the technique of distraction osteogenesis should be credited to the German craniofacial surgeons Rosenthal for the bone lengthening of the mandible in a microgen patient in 1927. The procedure is described and the original schedules and case are presented.

Facial bone distraction osteogenesis for correction of malocclusion: a more than 70-year-old concept in craniofacial surgery.

Bone distraction has been used increasingly since McCarthy and associates showed in their clinical investigation new osseous formation in the elongated area while performing mandibular distraction in 1992. However, at the craniofacial skeletal level, the initial description of the classic technique of distraction osteogenesis should be credited to German craniofacial surgeons Rosenthal (for bone lengthening of the mandible in a microgenia patient around 1927) and Wassmund (for the clinical advancement of a maxilla in a patient with hypoplasia of the upper jaw in 1926). Both procedures are described, and their original schedules and cases are presented.