Matthias Kelker

Publications of Matthias Kelker

• Comparison of laboratory and immediate diagnosis of coagulation for patients under oral anticoagulation therapy before dental surgery.

  Authors: Birgit Kruse-Loesler, Matthias Kelker, Johannes Kleinheinz

  Head & face medicine. 11/2005; 1:12.

  BACKGROUND: Dental surgery can be carried out on patients under oral anticoagulation therapy by using haemostyptic measures. The aim of the study was a comparative analysis of coagulation byBACKGROUND: Dental surgery can be carried out on patients under oral anticoagulation therapy by using haemostyptic measures. The aim of the study was a comparative analysis of coagulation by laboratory methods and immediate patient diagnosis on the day of the planned procedure. METHODS: On the planned day of treatment, diagnoses were carried out on 298 patients for Prothrombin Time (PT), the International Normalised Ratio (INR), and Partial Thromboplastin Time (PTT). The decision to proceed with treatment was made with an INR < 4.0 according to laboratory results. RESULTS: Planned treatment did not go ahead in 2.7% of cases. Postoperatively, 14.8% resulted in secondary bleeding, but were able to be treated as out-patients. 1.7% had to be treated as in-patients. The average error between the immediate diagnosis and the laboratory method: 95% confidence interval was -5.8 +/- 15.2% for PT, -2.7 +/- 17.9 s for PTT and 0.23 +/- 0.80 for INR. The limits for concordance were 9.4 and -21.1% for PT, 15.2 and -20.5 s for PTT, and 1.03 and -0.57 for INR. CONCLUSION: This study showed a clinically acceptable concordance between laboratory and immediate diagnosis for INR. Concordance for PT and PTT did not meet clinical requirements. For patients under oral anticoagulation therapy, patient INR diagnosis enabled optimisation of the treatment procedure when planning dental surgery.

• Potential and limitations of cephalometric analysis of maxillofacial bone movement in the case of LeFort III-distraction.

  Authors: Carsten Lippold, Gholamreza Danesh, Ulrich Meyer, Ariane Hohoff, Matthias Kelker, Johannes Kleinheinz

  Journal of orofacial orthopedics = Fortschritte der Kieferorthopädie : Organ/official journal Deutsche Gesellschaft für Kieferorthopädie. 10/2005; 66(5):388-96.

  BACKGROUND UND METHOD: The treatment of craniofacial deformities by means of distraction osteogenesis has become an established therapeutic procedure. Evaluation of the success of an operation isBACKGROUND UND METHOD: The treatment of craniofacial deformities by means of distraction osteogenesis has become an established therapeutic procedure. Evaluation of the success of an operation is usually carried out via conventional cephalometry. Conventional forms of analysis seem problematic due to surgically-induced changes in the skull base. In this study we investigated the movement of the midface in the presence of a syndromerelated surgical indication employing two different types of analysis, namely those of Ricketts and Delaire. RESULTS: It seems that neither procedure is suitable for determining this type of bone movement conclusively. Comparing the two, the Delaire analysis possessed greater informative value in view of the altered geometry, and a combination of both procedures made more exact determination possible of the final position achieved.