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Dive into the research topics where Heidrun Schaaf is active.

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Featured researches published by Heidrun Schaaf.


Oral Surgery Oral Medicine Oral Pathology Oral Radiology and Endodontology | 2010

Donor site morbidity after bone harvesting from the anterior iliac crest

Heidrun Schaaf; Stefan Lendeckel; Hans-Peter Howaldt; Philipp Streckbein

OBJECTIVES Autologous bone grafting is a common, standard procedure in maxillofacial surgery. We investigated complications of harvesting bone from the anterior iliac crest. STUDY DESIGN A retrospective analysis with a 2-year observational period included 75 patients who had undergone iliac bone grafting. Two techniques were examined: the closed osteotomy using a cylinder osteotome (Shepard) and an open procedure with a saw. RESULTS One major complication, a fracture of the anterior superior iliac spine, was observed (0.7%). Regarding long-term morbidity, 3 patients (4%) suffered from persistent pain and 2 (2.7%) from persistent sensory disturbance. A correlation by gender showed greater severity of pain directly after graft harvesting in women (P(Wilcoxon) < or = .001). Harvesting of corticocancellous blocks caused more pain than with the cylinder osteotome (P(Median) < or = .07). CONCLUSION The morbidity after iliac crest harvesting was found to be moderate to low, but the procedure is still necessary and frequently used.


Journal of Cranio-maxillofacial Surgery | 2012

Objectification of cranial vault correction for craniosynostosis by three-dimensional photography.

Jan-Falco Wilbrand; Alexander Szczukowski; Joerg-Christoph Blecher; Joern Pons-Kuehnemann; Petros Christophis; Hans-Peter Howaldt; Heidrun Schaaf

PURPOSE Correction of craniosynostosis is necessary in predominant cases. Surgical planning usually requires a preoperative CT to estimate the bony and intracerebral structures. A postoperative CT scan would involve a significant dose of radiation, which carries an elevated risk of malignant tumor development in later life. This study was performed to demonstrate the quality of three-dimensional (3D) photogrammetry when objectifying perioperative changes in craniofacial surgery. PATIENTS AND METHODS Twenty-eight patients with different premature craniosynostoses were analyzed photogrammetrically before and after surgical correction. 3D changes in cranial distances, symmetry and volumes were evaluated. A statistical covariance analysis excluded changes in cranial shape caused by physiological head growth. RESULTS The Cephalic Index in Scaphocephaly changed from 75.1% to a median value of 77.4%. The anterior symmetry ratio for coronal synostoses improved from 0.943 to 0.949 (a value of 1.0 represents perfect symmetry). The posterior symmetry ratio improved from 0.733 to 0.808 postoperatively in one single lambdoidal synostosis. In trigonocephaly, the median anterior skull volume rose from 528 to 601 ml. CONCLUSIONS 3D photogrammetry has great potential to track and objectify the clinical course of surgical correction of craniosynostoses. Craniofacial changes become highly reproducible and demonstrate clinical utility based on this technology.


Oral Surgery Oral Medicine Oral Pathology Oral Radiology and Endodontology | 2008

Sinus lift augmentation using autogenous bone grafts and platelet-rich plasma: radiographic results.

Heidrun Schaaf; Philipp Streckbein; Stefan Lendeckel; Kathrin Heidinger; Peter Rehmann; Rolf-Hasso Boedeker; Hans-Peter Howaldt

OBJECTIVES Autologous bone grafting and sinus floor elevation is a widely accepted method for reconstruction of the atrophic maxilla. The aim of this investigation was to examine the influence of platelet-rich plasma (PRP) on bone grafting in sinus floor augmentation. STUDY DESIGN A prospective, controlled, randomized study including 34 patients undergoing sinus augmentation before implant placement was designed. The intervention group had additional treatment with PRP. Radiographic imaging was performed by computerized tomography (CT) and panoramic radiography 4 months after augmentation and before implant placement. RESULTS Bone density showed no significant increase when PRP was used in combination with autologous bone grafting compared with autologous bone alone. CONCLUSIONS This study showed no positive effect of PRP on bone density in CT evaluation when used in sinus floor augmentation. Bone density in the CT showed no correlation to histomorphometric evaluation.


Journal of Craniofacial Surgery | 2010

Three-dimensional photographic analysis of outcome after helmet treatment of a nonsynostotic cranial deformity.

Heidrun Schaaf; Christoph Yves Malik; Philipp Streckbein; Joern Pons-Kuehnemann; Hans-Peter Howaldt; Jan-Falco Wilbrand

Cranial asymmetries due to nonsynostotic deformation of the skull have been reported with increasing frequency during the last decade. Conservative approaches using helmets and physiotherapy have been shown to be effective in their treatment. Traditionally, documentation has been carried out using anthropometric caliper measurements. The present study evaluates the use of a new three-dimensional photographic system in the improved validation of changes in head deformities. This prospective analysis introduces a new technique for digital anthropometric measurement. The study series comprised 181 children with nonsynostotic head deformities. Three-dimensional photographs were obtained before and after treatment with an orthotic helmet device. The oblique head diagonals and head width and length were measured from three-dimensional photographs using 3dMD customer software. The cranial vault asymmetry index, cranial vault asymmetry, and cranial index were compared before and after treatment. The measurements obtained on three-dimensional images were able to demonstrate significant improvement in early infant cranial deformity after treatment with an orthotic helmet. The cranial vault asymmetry index in plagiocephaly was reduced by 7.16%, and cranial vault asymmetry was reduced by 0.86 cm. The cranial index in brachycephaly decreased by 7.32%. In children with combined plagiocephaly and brachycephaly, the cranial vault asymmetry index improved by 5.77%, cranial vault asymmetry improved by 0.71 cm, whereas the cranial index changed by 5.48%. Three-dimensional photogrammetry can support treatment control in patients with deformational plagiocephaly. This new technology offers several advantages such as easy acquisition of images, detection of landmarks without patient movement, repeatable measurements without patient discomfort, and the opportunity for unbiased evaluation. Abbreviations: CVAI, cranial vault asymmetry index; CVA, cranial vault asymmetry; CI, cranial index


Journal of Cranio-maxillofacial Surgery | 2012

Complications in helmet therapy.

Jan-Falco Wilbrand; Martina Wilbrand; Christoph Yves Malik; Hans-Peter Howaldt; Philipp Streckbein; Heidrun Schaaf; Heiko Kerkmann

OBJECTIVE Helmet therapy is an established method to correct positional head deformity in early infancy. Side effects such as skin erythema or pressure sores are well known for helmet therapy, but not yet adequately discussed in current literature. PATIENTS AND METHODS Retrospectively, all patient-sheets of infants treated by individual orthotic therapy in the years 2007 and 2008 were sighted and complications were noted. Complications were classified and sorted by their frequency and descriptive statistics was performed. The treatment to cure complications was recorded and success in complication control was analysed. RESULTS Altogether, 410 patients fit the inclusion criteria for this investigation. Complications were apportioned into pressure sores, local ethanol erythema, unsatisfying fit of the helmet or loss of the helmet, skin infection, failed correction of head deformity, and subcutaneous abscess in one case. Non-compliance is to be noticed in a high number, but mainly occurred towards the end of the treatment period. CONCLUSION Helmet therapy represents a safe therapeutic tool for the correction of positional cranial deformity. Complications have to be clear in number and severity for parental elucidation. Most complications can easily be avoided or eliminated by proper instruction of the parents.


Vox Sanguinis | 2007

Topical use of platelet-rich plasma to influence bone volume in maxillary augmentation : a prospective randomized trial

Heidrun Schaaf; Philipp Streckbein; Stefan Lendeckel; K. Heidinger; B. Görtz; G. Bein; Rolf-Hasso Boedeker; K. A. Schlegel; Hans-Peter Howaldt

Background and Objectives  The atrophic posterior maxilla often requires restoration of the alveolar ridge due to a lack of bone quantity and quality before dental implant placement. The aim of this study was to verify the hypothesis that platelet‐rich plasma (PRP) has an influence on bone density in the maxilla after sinus floor elevation in combination with autologous cancellous bone from the iliac crest. Therefore, a randomized, prospective, controlled trial was set up in two centres.


The Cleft Palate-Craniofacial Journal | 2010

Accuracy of photographic assessment compared with standard anthropometric measurements in nonsynostotic cranial deformities.

Heidrun Schaaf; Jan-Falco Wilbrand; Rolf-Hasso Boedeker; Hans-Peter Howaldt

Objective Anthropometric landmarks of the skull have traditionally been used to describe cranial deformities resulting from nonsynostotic plagiocephaly or brachycephaly. Recently, digital photography has become an important tool for characterizing facial and cranial pathologies. The purpose of this study was to compare standard anthropometric cranial measurements with measurements taken from cranial photographs. Patients Standardized digital images in the supracranial view and cranial anthropometric measurements were obtained from 122 children between the ages of 3 and 15 months. The photographs were assessed using Quick Ceph® software. The cephalic index and cranial vault asymmetry index were used to indicate the degree of cranial deformity. Children were classified into plagiocephaly, brachycephaly, and the combination of both. To determine interobserver variability, two clinicians separately measured the cephalic index and cranial vault asymmetry index from digital photographs in 70 infants of the plagiocephalic group. Results To compare interassay reliability for these methods of obtaining the cephalic index and cranial vault asymmetry index, the differences between photographically and anthropometrically derived values were plotted against anthropometrically derived values alone (Bland-Altman plots). The photographic method satisfied the limits of agreement (cephalic index, 7.51%; cranial vault asymmetry index, 6.57%) and showed slightly lower values represented by the respective bias (cephalic index, 1.79%; cranial vault asymmetry index, 3.03%). Comparison between observers revealed excellent agreement, detected by the intraclass correlation coefficient of .982 for the cephalic index and .946 for the cranial vault asymmetry index. Conclusion Our results demonstrate that digital photography is a reliable tool for quantifying cranial deformities. Furthermore, it is rapid, noninvasive, and reproducible. However, we continue to use both methods in clinical practice.


Journal of Cranio-maxillofacial Surgery | 2008

High resolution imaging of craniofacial bone specimens by flat-panel volumetric computed tomography

Heidrun Schaaf; Philipp Streckbein; Martin Obert; Birgit Goertz; Petros Christophis; Hans-Peter Howaldt; Horst Traupe

INTRODUCTION The prototype flat-panel volumetric computed tomograph (fpvCT) provides a new 3D imaging technology with detailed high resolution by using large-area flat-panel X-ray detectors. The object of this study was to evaluate the benefit of high resolution imaging using the experimental fpvCT to visualise different types of human craniofacial bone pathology. The study proved the feasibility of performing an intraoperative evaluation of free margins in bone malignancies using fpvCT. MATERIAL AND METHODS In this study, 35 bone specimens of various pathological types were examined by fpvCT. fpvCT data were compared with pre-operative multislice clinical CT images as well as with post-operative histological findings. RESULTS Bone tumours can be visualised with their specific pathological architecture and infiltration structure faster and more precisely by fpvCT than by multislice CT. The analysis of the resection margins supports the surgical procedure intraoperatively, especially when an immediate reconstruction with bone transplantation is carried out. DISCUSSION The fpvCT has a superior image quality when compared with clinical CT systems. The imaging of the bone structure itself has been shown to be useful for the interpretation of osseous resection borders. Furthermore, it can facilitate the diagnosis of tumour progression, especially in areas that are difficult to access, such as the base of the skull.


Science & Justice | 2014

Estimation of legal age using calcification stages of third molars in living individuals

Philipp Streckbein; Isabelle Reichert; M.A. Verhoff; Rolf-Hasso Bödeker; Christopher Kähling; Jan-Falco Wilbrand; Heidrun Schaaf; Hans-Peter Howaldt; Andreas May

The increased number of adolescents and young adults with unknown or inaccurately given date of birth is a current issue in justice and legal medicine. The objective of this study was to determine the extent to which third molar calcification stages assessed on panoramic X-rays could be useful as additional criteria for forensic age estimation in living individuals, focusing on the legally important ages 17 and 18. In a retrospective multi-center study, the developmental stage of each individuals third molar was analyzed using Demirjians scale in 2360 cases. Additionally, sex, age and ancestry were assessed. Individuals with the lowest calcification stage of all present molars in stage H were ≥18 years with a likelihood of ≥99.05% in the female (n=388), and ≥99.24% in the male (n=482) population. The lowest calcification stage of all present third molars proved to be useful as an additional reliable criterion for the determination of an age ≥18 years.


Oral Surgery Oral Medicine Oral Pathology Oral Radiology and Endodontology | 2011

Comparison of miniplate versus lag-screw osteosynthesis for fractures of the mandibular angle

Heidrun Schaaf; Steffen Kaubruegge; Philipp Streckbein; Jan-Falco Wilbrand; Heiko Kerkmann; Hans-Peter Howaldt

OBJECTIVES Treating mandibular angle fractures is common in maxillofacial surgery. The aim of this study was to compare lag screw fixation and miniplates. STUDY DESIGN This retrospective investigation compared patients treated with miniplates (n = 24) and with lag screws (n = 21). Inclusion criteria were a solitary angle fracture without comminution or other reasons for load-bearing osteosynthesis. The main parameters for the outcome analysis were fracture gaps at 4 defined measuring points on postoperative radiography. Postsurgical complications were recorded. RESULTS Fracture gaps measured in panoramic radiographs differed significantly between the lag-screw (average 0.56 mm) group and the group using 1 miniplate (average 0.85 mm) and 2 miniplates (1.40 mm). Miniplate fixation resulted in a wider fracture gap, especially in the region of the lower margin of the mandible. CONCLUSION Lag-screw fixation demonstrated smaller fracture gaps compared with miniplate fixation.

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