International Poster Journal of Dentistry and Oral Medicine, 04/2001

At the conclusion of this presentation, the participant should be able to identify the additive therapeutic effects combining Paclitaxel and TNP-470 in head and neck cancer. Angiogenesis is essential for tumor growth and progression. In head and neck cancer a tight correlation for angiogenesis and tumor progression has been demonstrated. The study was conducted to evaluate if there are additive therapeutic effects combining Paclitaxel with the angiogenesis inhibitor TNP-470 in a mouse model for head and neck cancer. NMRI nude mice were inoculated with HNSCC-001 cell line. After 4 weeks of tumor establishment 4 mice were injected with TNP-470 s.c. (30 mg/kg) and Paclitaxel i.p (25 mg/kg) every other day for 12 days while 4 control mice received vehicle injections only. The tumor volume and body weight was measured every other day up to day 15, when all mice were sacrificed. Significant differences in tumor volume could be seen at day 8 of treatment. On day 15 of tumor volume was 739 ± 60 mm3 in the vehicle-treated group and 136 ± 55 mm3 in the TNP-470/Paclitaxel treated group (p=0,00001). The T:C ratio decreased gradually during the experiment, from 1,2 before treatment to 0,4 on day 15 when the animals were sacrificed. Neither in treatment nor in control group metastasis could be detected macroscopically and in histological examination. On day 15 the body weight in the control group was 22,3 ± 2,5 g and 30,8 ± 3,5 g in the TNP-470/Paclitaxel group (p=0,008). Previous studies have demonstrated that taxanes can decrease tumor progression. By the combination of TNP-470 and Paclitaxel the tumor growth was repressed in mice. Further investigation of this combination is warranted. Schlagwörter: TNP 470, Paclitaxel, xenograft model, nude mice, head and neck cancer, squamous cell carcinoma, angiogenesis

Preprosthetic vertical distraction in the anterior mandible. The distraction of the alveolar process in cases of severe bone atrophy or postraumatic defects represents an alternative to bone grafting. Especially when insufficient soft tissue is the limitating factor, distraction becomes the method of first choice. Different intraoral devices have been developed. The use of two different distraction devices was used in the treatment of the alveolar process of the anterior mandible. Treatment of partial edentulous and edentulous patients and distraction after oral implantation were performed. The advantages of distraction osteogenesis are lack of bone harvesting morbidity and simultaneous soft tissue reconstruction. Inspite of various overlapping the selection of the right type of device depends on the size of the bone segment and the absence or existence of teeth or endosseous implants inside the segment. Lingual displacement of the segment is the main complication. Therefore fixation of the distraction devices to neighboring teeth has to be performed or stable devices have to be used. Continuous follow up is needed to prevent complications. Schlagwörter: vertical distraction, distraction osteogenesis, preprosthetic surgery

Patients with skeletal malocclusion often show functional TMJ - disorders, which frequently are due to the imbalance of the stomatognathic system. Therefore in orthognatic surgery it is mandatory to reestablish a biomechanic equilibrium by harmonizing the profil under the esthetic point of view at the same time. Developing a three-dimensional double splint method together with a new designed repositioning device a controlled three-dimensional repositioning of the mandible and maxilla will be achieved. Using this model-repositioning device the mantainmence of a centric position of the condyles is prevailed intraoperativly and allows a three-dimensional predictable and reproduceable three-dimensional positioning of the osteotomized jaw segments in orthognathic surgery. The first part of this article describes the technical details for the splint fabrication and the in second part clinical cases and the surgical outcome will be outlined. Schlagwörter: Orthognathe Chirurgie, Kiefergelenkfunktion, 3D Positionierung

The Accuracy of Bed Implant Processing with the Aid of Drill Templates. - A Mathematical Depiction of the Tolerance Limits -Introduction:In the process of planning and drill templates, the drilling of the implant takes place after putting the templates on the teeth with guidance of titanium sleeves that are inserted into the templates in the desired positions of the implant. The maximum tolerance limits that naturally appear on the tip of the drill after guided drilling over template anchored titanium sleeves are to be determined with assistance of a simple mathematical model.Materials and Methods:Three basic processes (process 2: illustration 1a and chart 2, process 3: illustration 1b and chart 3) that occur individually or combined are to be differentiated from the deviation of the drilling to the desired drilling direction. The maximum drilling deviation in the area of the drill tip when drilling with a 2 mm preparatory twist drill (firm Nobel Biocare) up to 13 mm mark of length is calculated for two types of sleeves: sleeves along the lines of Yildrim (firm Nobel Biocare), and steco-titanium sleeves (firm Steco System Technology).Results:The maximum deviation at the drill tip is calculated as follows:Process 1(with parallel shifting of the drill):the maximum drill deviation is equivalent to the tolerance limit between drill and sleeve (a).Process 2(tilting of the drill to the level of the upper edge of the sleeve, illustration 1a, chart 2):for the angle (angle divergence of the drill to the sleeve axle during rotation and translation) as follows:see b).The drill deviations at the drill tip in the X and Y axles can be deduced from this as follows:See c) and d).dB: drill diameter, dH: sleeve diameter, LB: drill length, LH: sleeve lengthProcess 3(during torsion of the fixture, illustration 1b, chart 3):The following angle divergences for the drill result by torsion of the sleeve fixture:See e), f) and g).Conclusion:The maximum horizontal deviations when tilting the drill (illustration1a, chart 2) and when twisting the joint sleeve to tooth (illustration 1b, chart 3) are between 0,2 and 0,4 mm. The deviation of the drill when twisting can be neglected while doing so. The horizontal deviation when moving the drill parallel (process 1) corresponds to the tolerance limit between the drill and sleeve and lies maximum between 0,19 mm (Yildrim sleeve) and 0,4 mm (steco sleeve). A better coordination of the workpieces drill-sleeve is called for considering the fact that with further suportless drilling, or else like with the steco sleeve partly guided drilling, additional tolerance limits appear and then lie clearly above 0,5 mm. Schlagwörter: implant, drill template, guidet drilling, tolerance, implant position

Since 20 years, calcium phosphate compounds are used as bone substitutes.In this study, three commercial ß-TCP preparations (Cerasorb, Bioresorb and Biovision) were examined in regard of their crystallinity (scanning electron microscopy), external porosity (section preparations) and chemical composition (x-ray-difractome-try). REM-pictures show significant differences in the crystallinity of the three preparations. These results were confirmed by testing the compressive strength of single particles. With a value of 5 N, Cerasorb showed the maximum stability, which is indeed about 20 times lower than that of bone. The external porosity of the material in the erosion is crucial for the process of bone growing in. In this regard, the preparations showed no significant differences. Their median values varied in a range between 40 to 58%. By the help of x-ray-difractometry, aside from the main component Ca3(PO4)2 (whitokit synth.), contaminations were discovered in all three preparations. The contaminations formed phases with concentrations under 0,5%. In Cerasorb, phases of CaH2P2O7 and CaH2P2O5 were detected. Bioresorb was contamined with phases of Ca3(PO4)2 x H2O, Ca5(PO4)3(OH), Ca2P2O7 and CaHPO4 x 2H2O. The purest preparation was Biovision with the two contamining phases Ca2P2O7 and Ca5(PO4)3OH in a concentration less than 0,2%. Among all examined preparations, Cerasorb showed the best crystallinity. The preparations did not differ in regard of their external porosity. Non of the preparations is free from contaminations. The existence of contamining phases indicates, that technological parameters in the production process of ß-tricalcium phospate hinder the complete crystallisation of whitokit. The biological significance of contaminations in ß-TCP should be investigated in histological and clinical studies. Schlagwörter: beta-Tricalciumphospates, beta-Tricalciumphospates

Previous studies have shown that silicone oil (dimethylsiloxane) and organic oils have a plaque-inhibiting activity, when they are used for oral rinsing. To determine whether organic oils would also influence the inflammatory reaction in periodontitis, we performed a double blind clinical study using soy oil for subgingival irrigation prior to scaling. Twenty patients with at least 3 teeth (test-teeth) in the upper jaw with probing pocket depth >= 5mm were randomly divided into 2 groups. The following clinical parameters were assessed: A modified plaque index (PLI) at 4 sites/tooth, pocket depth (PD), attachment level (AL) and bleeding upon probing (BOP) at 6 sites/tooth. All measurements were performed with an electronic probe (Florida Probe®). Prefabricated acrylic stents were used for AL measurements. Two weeks after repeated supragingival prophylaxis, patients were analyzed at baseline, days 1, 3, 15, 28 and 90. All teeth with PD >= 5 mm were irrigated with either 1 ml soy oil (99%) (Test group = Tg) or NaCl (Control group = Cg). Our preliminary results showed a reduction in BOP at the test teeth after day 15 in the two groups (BOP=from 38.3% to 28.8% at Tg, and from 41.6% to 27.2% at Cg). This is probably due to the reduction in PLI from approximate 40% before baseline to almost 15% in both groups and indicates the therapeutic effect of subgingival irrigation irrespective of the solution used. PD and AL showed a (non-significant) reduction in both groups. We conclude that the use of soy oil for subgingival irrigation prior to root planing, doesn't markedly influence clinical signs of inflammation. Schlagwörter: periodontitis, subgingival irrigation, oils

An 18 years old boy was admitted with a rare type of severely dislocated fracture of the posteriolateral aspect of the right orbital wall. At admission ophthalmologic examination revealed no light reception whereas neurophysiological testing showed a normal retinal response (ERG) and a pathological but still reproducible VEP (flash). Immediate surgical intervention and high dose corticoid therapy (methylprednisolon: bolus injection: 30mg/kg body weight and subsequent 5.4mg/kg body weight) led to full clinical and neurophysiological recovery of the optical nerve function after complete unilateral blindness within the following 2 hours. In addition to clinical examination and radiological diagnosis initial neurophysiological testing (ERG, VEP) of the retinal and optical nerve function are essential in order to obtain adequate information for the necessary therapeutic procedure in case of severe trauma of the orbita. Schlagwörter: optic nerve, VEP, trauma, fracture

Median cleft lip is a rare congenital anomaly. It may appear in the upper or in the lower lip ranging from a lip fissure to a complete cleft with or without brain deformity. Early surgical correction is indicated even when minimal expression of the deformity is present. A six week old baby was presented with a minimal expression of a median cleft in the upper lip. Clinically, it occured as a skin insertion in the midline of the vermilion. In the follow-up there occured a gap in the muscle midline and a midline diastema. At the age of 12 month the surgical correction was performed. Intraoperatively a dermoid cyst was seen, which caused a gap in the orbicularis oris muscle and a midline cleft of the intermaxillary bone. Schlagwörter: Dermoidzyste, mediane Lippenspalte, Diastema mediale, Lippenfissur

When vascular complications are suspected after microsurgical transfer of free fibula bone flaps without a skin island revisional surgery often proved to be unnecessary. Colour duplex sonography for the postoperative monitoring of bone grafts is demonstrated. The immediate postoperative monitoring and follow up of 12 free fibula bone flaps without a skin island by colour duplex sonography with a 7.5 Mhz scanner (Elegra®, Siemens, Germany) was performed. Using colour duplex sonography the perfusion of the vascular pedicle could be demonstrated in all 12 fibula flaps. In three patients vascular complications and failure of the flaps were suspected. Using colour duplex sonography adequate perfusion of the vascular pedicle was demonstrated immediately postoperatively and in the daily follow up. Therefore revisional surgery was not indicated. Colour duplex sonography is a reliable, non invasive and inexpensive method for the postoperative monitoring of free bone flaps. Schlagwörter: colour duplex sonography, microsurgery, free fibula flap, monitoring

The aim of this study about correction of hypertelorism was to test the hypothesis whether there is a predictable relationship between a three dimensional planning assessment for soft tissue changes as well as for movements of the osseous orbits or the occular globes and the surgical outcome. From 1996 to 1999 five patients (mean age 11 years, ranging from 5 to 35) underwent hypertelorism surgery in our clinic by combined intra- and extracranial approach. Scheme for surgery was calculated by a digital three dimensional computed tomographic (CT) scan model. Soft tissue distances were measured clinically. Bony conditions were evaluated pre- and postoperatively by three dimensional CT-scans. There was a strong correlation between bony structures in the digital predicition model and postoperative CT-scans. With reference to the bony reduction of intraorbital distance we found only a moderate correlation between intercanthal distance in the digital model and postoperative CT-scans or postoperative clinical measurement. Correlations between the digital model and postoperative CT-scans were stronger in vertical than in transversal movements of the orbits. We conclude that digital three dimensional planning assessment is a useful predictor in hypertelorism surgery not only for the bony outcome. Schlagwörter: hypertelorism, computer assisted 3D planning

Proteolytic enzymes from neutrophils play a decisive role in tissue destruction. They release from the granulocyte during the phagocytosis or by lysis. In addition to cathepsin D, cathepsin G and collagenase, elastase is a principal component in collagenfibers destruction. Not only elastin is affected by lysis produced from elastase, but also proteoglycanes, hemoglobin, fibrinogen and collagen. In 1975 Ohlsson and Delshammer investigated in gingival biopsies the connection between elastase concentration and the granulcytes contents. In diseased tissues the mean concentration of elastase was 0,1 µg/mm3. That concentration means a proportional content of 25.000 granulocytes. Kowashi and Cimasoni (1980) reported a connection between periodontal destruction and proteolytical activity in the gingival crevicular fluid flow. Important for tissue disintegration and destructive processes is not only the enzymatical concentration, but also the activity. Kenneth et al. (1995) reported about a periodontal disease progression with an amount of over an elastolytical activity from 300 µU/µl. Elastase can appeare as a complex with the alpha-1-proteinase-inhibitor or alpha-2-macroglobulin respectively. Schlagwörter: Elastaseaktivität, Diagnostik, Mikrotest, Parodontitis

The photography shows an aid highly qualified to identify unknown bodies conserving characteristics of the bones of the upper and lower jaws, the teeth and dental restaurations as well. It enables the storage of characteristics of dentures.Already one photograph allows to support information about the multitude of dental details and may lead to an identification. Schlagwörter: documentation, forensic odontology, identification, law, photography, unknown bodies

Distraction of the facial skeleton in case of severe deformities or malformations needs detailed and exact planning. In craniomaxillofacial surgery advances in imaging techniques and associated technologies have led to improved preoperative planning. Stereolithography models however do not fulfill the requirements for complex cranio-maxillofacial plastic and reconstructive procedures i.e. preoperative planning with virtual correction, intraoperative navigation and postoperative control. On the base of an axial spiral CT data set in our clinic an optical navigation system is used for preoperative planning and intraoperative controlling of tumor resection, adjuvant chemo- or radiotherapytherapy and complex cranio and maxillofacial reconstruction. We present the use of this technique for midface and mandible distraction. Preoperative planning including positioning of the distraction devices, navigational guided osteotomies and postoperative control will be demonstrated. Schlagwörter: computer assisted surgery, distraction osteogenesis, maxillofacial surgery

In Europe and in the USA, approx. 175 to 740 bite injuries per 100,000 inhabitants occur. Among the animal bites 90% are dog bites, which happen mostly before age of 10 years with a maximum between 5 and 9 years. While in adults dog bites are most often on the limbs, in children the face is involved in up to 78%. The necessity of surgical treatment depends on the severity of the injury. The typical characteristic of a dog bite is the high masticatory force of 50 - 100 kg per qcm, leading large areas of avital tissue. These masticatory forces lead to typical injury patterns ranging from superficial wounds to severe tissue defects including bone. Infected bite injuries generally should additionally be treated by i.v. antibiotics. Until the microbiological test result is present, treatment with beta-lactamase-resistant penicillin or combinations (e. g. amoxicillin and clavulan acid) is recommended. Extensive, long-lasting flushing of the wound with high intensity, eventually with pressure, is indicated. In general, maximum tissue preservation in the face is indicated. In the face, a primary wound closure after extensive cleaning of the wound is regarded as indicated. We report on two 2 yrs old children, who both suffered from severe dog-bites by major periorbital lacerations including the eye-lid apparatus, lacrimal drainage system, disruption of the left malar bone and NOE fractures. In one patient the mandible was bit through and the great cervical vessel exposed. The management of these severe injuries is demonstrated showing the advantage of an interdisciplinary approach to reconstruct the patients primarily. In both patients primary wound healing occured. Schlagwörter: Bissverletzung, Gesichtsverletzung, Traumatologie