PubMed Health⌕ Search

Biomedical subjects

R Dempf

Publications and source records attributed to R Dempf.

16 recordsLinked to original sources
PubMed2006

Reconstruction of orbital wall defects with calcium phosphate cement: clinical and histological findings in a sheep model.

The aim of this pilot study was to investigate the potential of calcium phosphate cement in the treatment of orbital wall defect fractures in an adult sheep model, and to compare this alloplastic material to autologous calvaria split-bone grafts. Clinical, volumetric and histological examinations were carried out of both reconstruction materials. The use of cement made intraoperative corrections easier to perform, and increased the precision of reconstruction of the orbital volume. This material also proved to be osseoconductive. The two materials were used successfully in combination. Regions of most intensive remodelling were the anterior orbital floor and the adjacent orbital rim. The preliminary results of this study demonstrate the potential of calcium phosphate cement as a useful biomaterial in the reconstruction of the anterior orbital region. Further animal and clinical trials are necessary to investigate its ability as a carrier for mediators where bone healing requires influence or support.

Animals↗
PubMed2005

Dental implants in patients with orofacial clefts: a long-term follow-up study.

Aim of this study was to determine the success of implants that were inserted in patients with cleft of the lip, alveolus and palate (CLAP) and to identify prognosis-relevant factors. In a prospective evaluation, 75 implants inserted in combination with bone grafting at cleft sites of 45 patients were examined. The observation period extended 5.5 years in average (minimum 1.5, maximum 11.3 years). Implant success was evaluated clinically and radiographically and was compared to age- and gender-matched control groups. Statistic assessment included Kaplan-Meier survival analysis, Log rank tests and Cox regression analysis. In total, 10 implants were lost in 8 patients, resulting in an implant survival rate of 82.2% at the end of the observation period. Patient-related parameters of age, gender or type of cleft had no significant influence. The length of an implant was significantly related to an improved survival rate (P<0.01). Implant survival was less in CLAP patients when compared to implant insertions in a non-cleft control group, but improved when compared to patients with bone grafting for other indications. It is concluded that implants combined with bone grafting can offer a reliable alternative in patients with CLAP.

Adolescent↗
PubMed2004

Ortho- and heterotopic bone grafts in bifocal transport osteogenesis for craniofacial reconstruction--an experimental study in sheep.

Bifocal transport osteogenesis (BTO) is a promising technique for the reconstruction of extended osseous craniofacial defects. Aim of this study was to determine the potential of this technique related to various donor sites of the transport segment. In 10 adult sheep critical size defects of the calvaria were treated by gradual movement of a transport segment consisting either of autogenous regional free calvarial bone grafts (n=5) or autogenous illiac free bone grafts (n=5). Latency period was 5 days; the rate of distraction was 1mm per day and extended approximately 40 days. The consolidation period was 28 days. After harvesting, specimens were investigated by conventional radiography, CT-scans, histologically and by fluorescence. In both groups transport osteogenesis resulted in a complete closure of the critical size defect. Membranous bone formation and remodeling occurred during the entire period of distraction and consolidation. The volumes and thickness of newly formed bone at the defect site were increased significantly when calvarial bone grafts were used (P<0.05). Iliac bone grafts became progrediently smaller during distraction, while the volume of calvarial grafts remained relatively constant (P<0.05). In conclusion, transport segments consisting of calvarial and iliac bone resulted in a reliable closure of craniofacial critical size defects in adult organisms; the application of calvarial bone grafts resulted in an increased extend of bone formation.

Animals↗
PubMed2003

[Normal nasalance for the German language. Nasometric values for clinical use in patients with cleft lip and palate].

OBJECTIVE: Rhinophonia is often present in patients with cleft lip and palate (CLP) many years after palatoplasty. It may be caused either by organic deficits, functional disorders, or both. NasalView is known as an instrument for the objective assessment of nasalance in cases of velopharyngeal insufficiency or incompetence.However,normative values for the German language are not yet available. In order to overcome this problem, this study evaluated such norms using NasalView. METHODS: A total of 50 individuals with normal speech development were examined with NasalView. The median age was 14 years (range 11-20 years). The tone material used comprised the vowels /a:/, /e:/, /i:/, /o:/, /u:/, the sentences S(1): "Die Schokolade ist sehr lecker."("This chocolate is very tasty.") and S(2): "Nenne meine Mamma Mimmi."("Call my mummy Mimmi."), and the text passages of LT(1): "Nordwind und Sonne"("Northwind and sun"), LT(2): "Kindergeburtstag"("A child's birthday party") and LT(3): "Der grosse Gesang"("A famous song"). RESULTS: The mean nasalance for the vowels was 35.9% (+/-8.4), for S(1) (containing no nasal consonants) 24.9% (+/-5.3), and for S(2) 69.6% (+/-5.5) (with many nasal sounds). The results for the text passages were 42.1% (+/-4.2) for LT(1), 36.9% (+/-4.3) for LT(2) and 38.2% (+/-4.4) for LT(3). CONCLUSION: The norms of nasalance for the German language presented here may be useful in measuring the long-term outcome of cleft lip and palate.

Adolescent↗
PubMed2002

Midfacial morphology in children with unilateral cleft lip and palate treated by different surgical protocols.

The purpose of this study was to compare cranio-facial, particularly midfacial morphology, in two groups of children with complete unilateral cleft lip and palate (UCLP) treated at two different cleft centres (Hannover. Germany and Brussels, Belgium) following different surgical treatment protocols. A total of 62 children (40 males; 22 females) with non-syndromic UCLP were included in this study at approximately the age of 10. The Hannover group comprised 36 children, who had repair of the lip at a mean age of 5.83 +/- 1.16 months, followed by repair of the hard and soft palate at a mean age of 29.08 +/- 4.68 and 32.25 +/- 4.29 months. respectively. The Brussels group consisted of 26 children who underwent surgical treatment according to the Malek protocol: the soft palate was closed at a mean age of 3.04 +/- 0.20 months, followed by simultaneous repair of the lip and hard palate at a mean age of 6.15 +/- 0.68 months. Midfacial morphology was evaluated by means of cephalometric analysis according to Ross. The children in the Hannover UCLP group did not differ significantly from those in the Brussels group in the anteroposterior dimension of the midface. However, the maxillary plane was significantly more open in the Brussels group due to less posterior vertical maxillary development.

Age Factors↗
PubMed2002

Cranio-facial distraction osteogenesis: a review of the literature. Part II: Experimental studies.

In this study the literature dealing with experimental cranio-facial distraction osteogenesis (DO) was reviewed. A PUBMED search (National Library of Medicine [NCBI] revised 1 April 2001) from 1966 through December 2000 was conducted. Key words used in the search were: distraction, lengthening, mandible, mandibular, maxilla, maxillary, midface, midfacial, monobloc, cranial, cranio-facial, maxillofacial. This search revealed a total of 120 experiment-orientated articles that were all analyzed in detail in this study. The purpose of the experimental study, animal model, animal growth status, type of distraction, type of surgery, distraction rate and rhythm, latency and contention period, amount of lengthening, relapse, complications and nature of the distraction device were analyzed. This review revealed that a total of 1207 animals were used in seven different animal models for research on cranio-facial DO: 54 using dogs (45.0%), 25 using rabbits (20.8%), 18 using sheep (15.0%), 11 using minipig (9.2%), seven using monkeys (5.8%), four using rats (3.3%) and one using a cat model (0.8%). Based on the results of this study, an attempt was made to provide biological DO parameters and guidelines for future research on experimental cranio-facial DO related to the appropriate animal model.

Animals↗
PubMed2002

[Extracorporeal shockwave lithotripsy for treatment of sialolithiasis of salivary glands].

BACKGROUND: Following the clinical introduction of extracorporeal shockwave lithotripsy in the 1980s for the treatment of sialolithiasis of salivary glands this method has been widely used and replaced surgical interventions in selected patients. PATIENTS: Between 1/1995 and 1/1999 35 patients were treated by extracorporeal shockwave lithotripsy (ESWL) with the "Minilith SL-1" lithotripter on an outpatient basis. Radiography and sonography were performed to verify sialolithiasis and scintigraphic investigation was done to control sufficient gland function. Treatment was performed in a fractionated manner with up to 3000 shockwaves per session, normally without anesthesia or analgosedation. RESULTS: After treatment 45.4 % of the patients with sialolithiasis of the parotid gland (n = 11) were stone-free and in 36.3 % an adequate desintegration of the stones was achieved. These patients underwent 2.6 sessions on average for sufficient stone-destruction. 41.6 % of the patients with sialolithiasis of the submandibular gland (n = 24) were stone-free and 3.1 sessions were necessary on average. Desintegration of the stones was achieved in 25 %. Mild pain, swelling, bleeding out of the intraoral orifice of the affected gland and skin petechia were the only complications. All patients were symptom-free after lithotripsy, although fragmented stones persisted in the parotid gland (18.3 %) and the submandibular gland (33.4 %). CONCLUSIONS: The advantages of ESWL are the relatively painless treatment and the elimination of the need for an operation with its surgical risks.

Adolescent↗
PubMed2001

[Effectiveness of botulinum toxin A in the treatment of gustatory sweating].

Frey's syndrome is present in almost all patients after parotidectomy. Gustatory sweating reduces quality of life. Injections of botulinum toxin A have recently been described as effective. This study was designed to evaluate the efficacy of this new treatment. Nineteen patients with severe gustatory sweating following superficial parotidectomy were treated. One unit/cm2 botulinum toxin A was injected intracutaneously into the affected area once. Minor's starch iodine test was performed to prove the outcome of therapy 4 weeks later. Eight patients lost their sweating. However, another seven patients had some blue spots on their cheeks. In four patients whose sweating had extended beyond the hairline, remnants of gustatory sweating showed up. Overall, the affected area of gustatory sweating could be reduced by botulinum toxin A from an average of 31 cm2 before treatment to 4 cm2 after treatment. Although there were some remnants of sweating in a few patients, Frey's syndrome was gone in all cases. No side effects could be observed. Intracutaneous injections of botulinum toxin A are highly effective and safe in treatment of gustatory sweating.

Adult↗
PubMed2001

[Autogenous bone transplants in repair of the traumatically damaged orbit. Functional and esthetic results in 42 cases].

BACKGROUND: Autogenous bone transplantation is a well established aspect of craniofacial traumatology. This study evaluated functional and esthetic success in repairing traumatically damaged orbits by autogenous bone transplantation. PATIENTS AND METHODS: We repaired 102 osseous orbital defects by autogenous bone transplantation, 98 by calvarium split graft and 4 by iliac crest transplant. Of 42 surgical patients 34 were followed up. RESULTS: Autogenous bone transplants have proven themselves for repair of traumatically damaged orbits. Calvarium split grafts are particularly suitable for this purpose. Good esthetic and functional results can usually be achieved with primary osseous defect repair. However, more protracted functional defects can often no longer be helped. CONCLUSION: Autogenous bone transplants can be broadly recommended for providing primary care.

Bone Transplantation↗
PubMed2001

[Immunohistochemical localization of insulin-like-growth-factor-binding protein 6 in the head area of the mouse].

BACKGROUND: The insulin-like growth factor (IGF) system is an important regulator of cell growth and differentiation. The mitogenic and metabolic activities of IGFs are modulated by a family of six high-affinity IFG binding proteins (IGFBPs). IGFBP-6 is unique among the IGFBPs in its preferential binding of IGF II. METHODS: In this study, specific antibodies against recombinant mouse IGFBP-6 generated in chicken were used to localize IGFBP-6 by immunohistochemistry in the head region during late embryonic and newborn mice. RESULTS: Immunoreactivity was detected in oral and nasal mucosa, tooth-forming anlage, anlage of skeletal muscle, anlage of submandibular glands, enchondral ossification, and osteoclasts.

Animals↗
PubMed2001

Craniofacial distraction osteogenesis: a review of the literature: Part 1: clinical studies.

A review of the literature dealing with distraction osteogenesis (DO) of the craniofacial skeleton, provided by a PUBMED search (National Library of Medicine, NCBI; revised 3 April 2000) from 1966 to December 1999 was conducted. Key words used in the search were distraction, lengthening, mandible, mandibular, maxilla, maxillary, midface, midfacial, monobloc, cranial, craniofacial and maxillofacial. This search revealed 285 articles. One hundred and nine articles were clinically orientated and were analysed in detail in this study. The type of distraction, indications, age, type of surgery, distraction rates and rhythms, latency and contention periods, amount of lengthening, follow-up period, relapse, complications and the nature of the distraction device were analysed. This review revealed that 828 patients underwent DO of the craniofacial skeleton; 579 underwent mandibular DO, 129 maxillary DO, 24 simultaneous mandibular and maxillary DO and 96 midfacial and/or cranial DO. Craniofacial DO has proven to be a major advance for the treatment of numerous congenital and acquired craniofacial deformities. Treatment protocols and success criteria for craniofacial DO are suggested on the basis of these results. There is still, however, a lack of sufficient data, especially on follow-up and relapse, so that treatment strategies have to be validated by long-term studies in the future.

Adolescent↗
PubMed2000

Lesions of the inferior alveolar nerve arising from endodontic treatment.

A lesion of the IAN following endodontic treatment of the lower molars and premolars is not a rare event and presents an uncomfortable situation both for the dental surgeon and the patient. Injury can result on the one hand by direct intrusion of the instrument through the apex into the mandibular canal, and on the other by the filling material which becomes forced into the mandibular canal. In the latter case, a nerve lesion will only result when the filling material contains neurotoxic substances such as paraformaldehyde. With a direct lesion or when forcing of resorbable filling material into the mandibular canal is suspected, one should first employ a wait-and-see approach, because usually the only nerve damage is in the form of neuropraxy or axonotmesis for which there is a high rate of spontaneous regeneration. However, if neurotoxic filling material is introduced into the direct vicinity of the nerves, the mandibular canal should be opened and the filling material should be removed as early as possible. If the filling material is forced directly within the endoneurium between the nerve bundles, the damaged nerve sections must be resected and bridged using transplants from the sural or greater auricular nerves.

Adult↗
PubMed1998

[Experiences with distraction osteogenesis in therapy of severe peripheral airway obstruction in infancy and early childhood].

Children with craniofacial malformations are at special risk for the development of peripheral airway obstruction. The problems are magnified in patients with retroposition or hypoplasia of the mandible. In these cases, the base of the tongue is posteriorly displaced, hereby decreasing the airway diameter. By application of distraction osteogenesis the mandible can be lengthened to move the base of the tongue forward and open the airway. Three female patients aged between 7, 11, and 15 months suffering from peripheral airway obstruction caused by mandibular hypoplasia were treated by gradual distraction. All of them had a gastrostomy or a nasogastral tube in place, respectively, due to severe nutrition problems. In the youngest patient tracheostomy was performed shortly after birth and was already planned in the 15-month-old child, who had received a permanent nasopharyngeal tube. The 11-month-old child suffered from severe refractory sleep apnea. Exercises in oral feeding were possible in the youngest patient after 10 days of distraction. In the oldest one, the airway tube was removed on the six day of distraction and, thus, tracheotomy was successfully avoided. In the 11-month-old child apneic events a rapidly decreased. Our experience suggests that distraction osteogenesis after careful preoperative evaluation can be successfully performed for the treatment of peripheral airway obstruction in patients with selected craniofacial anomalies.

Airway Obstruction↗
PubMed1993

A technique for diagnosing the individual patterns of innervation of the trapezius muscle prior to neck dissection.

Based on the techniques of regional anaesthesia, a method for simulating the effects of radical neck dissection on the innervation of the trapezius muscle by selectively and reversibly blocking the accessory nerve and its superficial cervical anastomoses, was developed and tested on 40 patients who were due to undergo radical neck dissection. Action potentials of the three portions of the muscle were recorded after this blockade as well as after radical neck dissection, and compared. It was found that the electromyograms were congruent in 92.5% of the cases. Four patterns of innervation were demonstrated, ranging from complete substitution of the resected or blocked nerves to a remaining muscle activity of less than 20% after blockade or radical neck dissection.

Accessory Nerve↗