Biomedical subjects

K Würzler

Publications and source records attributed to K Würzler.

3 recordsLinked to original sources

PubMed2003

[Bimaxillary osteotomy with and without condylar positioning--a 1981-2002 long-term study].

PURPOSE: The introduction of the four-splint technique in our hospital in 1997 made possible the reproducible centric condyle positioning in bimaxillary osteotomies, while taking the auto rotation of the mandible into consideration and avoiding steps in the mandibular osteotomy line. PATIENTS AND METHODS: From 1981 to 2002 a total of 622 patients underwent bimaxillary osteotomy surgery. During 1981-1997 a total of 395 patients (63.5%) underwent surgery without or only with centric condyle positioning in sagittal ramus osteotomy of the mandible. During 1997-2002 a total of 227 patients (36.5%) underwent surgery with continuous centric condyle positioning with the four-splint technique. RESULTS: In patients with preoperative functional disorders, surgery with continuous centric condyle positioning resulted in statistically significant (p<0.05) improvement compared to those who underwent surgery without continuous centric condyle positioning. CONCLUSION: The results confirm the indication for continuous centric condyle positioning in bimaxillary osteotomies.

Dental Occlusion, Centric↗

PubMed2003

[Typical features of craniofacial growth of the FGFR3-associated coronal synostosis syndrome (so-called Muenke craniosynostosis)].

BACKGROUND: The FGFR3-associated coronal synostosis syndrome (Muenke craniosynostosis) is caused by a point mutation (C749G) on the FGFR3 gene resulting in a Pro250Arg substitution. METHODS: To characterize this malformation, the neuro- and viscerocranium were analyzed by axial CT scans of the skull and cephalometric radiographs of up to 13 affected children before and in part after fronto-orbital advancement. RESULTS: Preoperative analysis of the intracranial volume of four patients showed a mean decrease of 3.6%, indicating a compensatory growth pattern of the skull in cases of coronal synostosis. The typical brachycephaly could be verified by the significant shortening of the skull length of 13.2% on average and by the significant reduction of the anterior cranial base length of maximal 5.9% on average. The anterior part of the skull was characterized by a significant mean increase of the intercoronal distance of 8.6%, which indicates a compensatory transversal growth in this malformation. The widened bilateral interorbital and anterior interorbital distances were increased by 7.3 or 9.0%, respectively, confirming a hypertelorism typical for this syndrome. The "frontal bossing" frequently found in brachycephaly was characterized by the preoperatively increased sagittal extension of the forehead (about 112.9% above the norm) and by the increased height of the frontal prominence (about 47.8% above the norm). Following surgery, both variables defining the morphology of the forehead were reduced and appeared to be constant throughout the follow-up. Hypoplasia of the midface described by Muenke et al. (1997) was confirmed in the present study only by the significant reduction of the sagittal length of the maxillary base, which was decreased by 6.8%. CONCLUSION: In accordance with the current literature, the skull configuration described for Muenke craniosynostosis shows similarities with the Saethre-Chotzen syndrome.

Amino Acid Substitution↗

PubMed1999

[EHBMP-2. Initial BMP analog with osteoinductive properties].

For the first time a non natural BMP-variant (EHBMP-2) with osteoinductive properties was produced by expression in E. coli through specific mutation of the amino acid sequence. The substitution of 12 N-terminal amino acids by a nonsense sequence results in a neglectible affinity of EHBMP-2 to the extracellular matrix. In vitro EHBMP-2 induces dose-dependent cartilage formation in neonatal muscle tissue. Single intramuscular implantation in mice results in the formation of an ossicle with functional active bone marrow. The size of the ossicle depends on the amount of implanted EHBMP-2 and can significantly be increased by the combination with a collagen carrier. The largest bone formation is observed after injection of EHBMP-2 containing collagen suspensions. In rats a stronger osteoinductive activity can be achieved by coupling of EHBMP-2 to collagen discs than by coupling natural BMP-2 to the same collagen carrier. Critical size defects in rats' mandibular angels can be restored by the combination of granular collagenous bone matrix (ICBM) with EHBMP-2. Further investigations have to show whether the altered pharmacokinetics of EHBMP-2 has advantages regarding its therapeutical use and tissue-engineering.

Amino Acid Substitution↗