Comparison of alendronate and sodium fluoride effects on cancellous and cortical bone in minipigs. A one-year study.

Fluoride stimulates trabecular bone formation, whereas bisphosphonates reduce bone resorption and turnover. Fracture prevention has not been convincingly demonstrated for either treatment so far. We compared the effects of 1-yr treatment of 9-mo-old minipigs with sodium fluoride (NaF, 2 mg/kg/d p.o.) or alendronate (ALN, 4 amino-1-hydroxybutylidene bisphosphonate monosodium, 1 mg/kg/d p.o.) on the biomechanical and histomorphometric properties of pig bones. As expected, NaF increased and ALN decreased bone turnover, but in these normal animals neither changed mean bone volume. NaF reduced the strength of cancellous bone from the L4 vertebra, relative to control animals, and the stiffness (resistance to deformation) of the femora, relative to the ALN group. In the ALN-treated animals, there was a strong positive correlation between bone strength and L5 cancellous bone volume, but no such correlation was observed in the NaF group. Furthermore, the modulus (resistance to deformation of the tissue) was inversely related to NaF content and there was a relative decrease in bone strength above 0.25 mg NaF/g bone. Moreover, within the range of changes measured in this study, there was an inverse correlation between bone turnover, estimated as the percentage of osteoid surface, and modulus. These findings have relevant implications regarding the use of these agents for osteoporosis therapy.

Double contrast small bowel follow-through with an acid-resistant effervescent agent.

RATIONALE AND OBJECTIVES: A new technique was developed to achieve double contrast examinations in the small bowel without intubation. METHODS: Effervescent granules and tablets were coated with an acid-resistant acrylic lacquer to provide selective enteric gas release. The coating thickness was 15% of dry weight for the granules and 1 to 4.5 mg/cm2 for the tablets. Fifty patients were examined using the method in a controlled study. All examinations were reviewed by two radiologists using a three-step quality score. The results were compared to 20 enteroclysis examinations. RESULTS: Image quality was better for the coated tablets compared with the granules (P < .01). The double-contrast small bowel follow-through (DC-SBFT) provided a better quality examination in the terminal small bowel than in the jejunum. Enteroclysis yielded better results for the jejunum, but was not superior in the terminal ileum. Average time of fluoroscopy was 477 seconds for the DC-SBFT (n = 50) compared with 952 seconds for patients receiving enteroclysis (n = 528). No side effects or adverse reactions occurred due to contrast media application. CONCLUSIONS: The results of this new method are preliminary, yet promising. For young patients and certain indications it may provide a less invasive alternative to enteroclysis.

[The computer-assisted processing of CT data in planning endosseous implantation interventions]. / Computerunterstützte Verarbeitung von CT-Daten bei der Planung enossal implantologischer Eingriffe.

The success of dental implantologic measures depends considerably on the correct positioning of the endosseous implants. A sufficient amount of bony substance is mandatory to provide overall covering of the implant with at least 1 mm of cortical bone. By the aid of a custom-developed software system, computed tomography image data can be handled on a conventional MS-DOS personal computer. The user is enabled to simulate size and positioning of the implant by interactive graphic animation. Quick and exact presentation is achieved by optimizing the computation algorithms. Storage needs are minimized by a segmentation procedure and additional compression of the image. Integrated patient data management and user friendly self-documenting program surfaces provide easy application.

[High-resolution CT of the dentate alveolar ridge in comparison with histological thin section preparations]. / Hochauflösende CT des bezahnten Alveolarkammes im Vergleich mit histologischen Dünnschliffpräparaten.

Human bone segments of the toothed jaw were scanned using high-resolution CT with axial and coronal contiguous 1 and 2 mm slices. The bone segments were sliced analogous to the performed CT image positions. Contact films and micro-sections were made from the cuttings. Length and width of the teeth, the thickness of the alveolar bone and the distance between bone and dental surface were measured. Comparison of the CT measurements with contact films and histological specimen yielded best results for axial slices with 1 mm slice thickness (mean error 0.3-0.5 mm). Coronary oriented slices showed an error of 0.3-1.6 mm. 3D-reformatting can improve spatial orientation for axially produced image series. For CT imaging of the toothed jaw concerning the dento-alveolar structures, contiguous axial scanning with 1 mm slice thickness appears to be the concept of choice.

[Computed tomographic imaging of the dentoalveolar-maxillary sinus lacuna of the dentate jaw]. / Computertomographische Darstellung der dentoalveolären Kieferhöhlenbucht des bezahnten Kiefers.

A human bone segment of the lateral maxilla was scanned using high-resolution computed tomography (CT) in contiguous parallel axis slices in order to image the topographical relationship between upper molars and the maxillary sinus. The bone segment was dissected analogously in 1 mm thick sections. After exposing contact films from these jaw cuttings, microsections were made for histological interpretation. The radiological-histological comparison between the CT-scans, contact films and the histologic specimens revealed absolute differences of 0.2-0.6 mm. The high resolution CT allowed an interpretation of details located between teeth and bone when the minimum bone thickness was 0.5 mm or more. First experiences with the CT-technique in orthodontic patients were promising, especially for the differential diagnosis of the dentoalveolar maxillary sinus relation.

Sialendoscopy for the diagnosis and treatment of juvenile recurrent parotitis.

PURPOSE: The aim of the current study was to analyze the use of sialendoscopy for the diagnosis and treatment of juvenile recurrent parotitis (JRP), note possible complications, and the rate of disease recurrence. We believe that this cutting edge procedure may be very effective both for the diagnosis and treatment of JRP, with few complications and low rates of recurrence. PATIENTS AND METHODS: A retrospective descriptive case study was conducted on a sample of patients presenting with JRP. Data was collected from the patient's medical records. Diagnostic sialendoscopy was performed to identify and classify the ductal pathology, treated by interventional therapeutic sialendoscopy. We carefully noted all complications and the disease recurrence rates. RESULTS: The patient sample included 50 children presenting with JRP (33 M, 17 F; age range: 2 to 16 years). Seven children presented with bilateral parotitis, the remaining 43 with unilateral parotitis. The study was conducted from 2003 to 2012. There was a statistically significant association between sialendoscopic data and the actual outcome. Seven children underwent additional sialendoscopy because of recurrence. They were all in the group of children presenting with unilateral parotitis. DISCUSSION: Our results validate the expected outcome. Sialendoscopy is an accurate technique for the diagnosis of JPR, and an effective tool for the treatment of JRP, with a low rate of complications and recurrence.

New insights in prism orientation within human enamel.

The knowledge about the orientation of the prisms in human dental enamel is mainly based on morphological observations (light optical, SEM, etc.). Hence there are many schematic drawings, showing the orientation as seen in the microscope. Locally resolved direct measurements of the orientations, proofing the observations, have not been done in detail up to now. X-ray diffraction methods adapted from material science are used in this study, providing directly the orientation of the crystallites in the examined positions. Hereby new and better detailed information was obtained, showing the orientation of the prisms and giving information about their intrinsic structure. Based on the measurements, existing prism orientation models can be enhanced and two structural suggestions can be made, showing possible inner building principles for the prisms. Future planned measurements will even allow deciding which of the two models is more likely.

Couvade syndrome: male counterpart to pregnancy.

Couvade is the common but poorly understood phenomenon whereby the expectant father experiences somatic symptoms during the pregnancy for which there is no recognized physiological basis. Symptoms commonly include indigestion, increased or decreased appetite, weight gain, diarrhea or constipation, headache, and toothache. Onset is usually during the third gestational month with a secondary rise in the late third trimester. Symptoms generally resolve with childbirth. Couvade has been seen as an expression of somatized anxiety, pseudo-sibling rivalry, identification with the fetus, ambivalence about fatherhood, a statement of paternity, or parturition envy. It is likely that the dynamics of couvade may vary between individuals and may be multidetermined.

Dental fluorosis associated with hereditary diabetes insipidus.

Among the characteristics of hereditary pituitary diabetes insipidus are polydipsia and polyuria from early infancy. Drinking of large amounts of water, even with lower than accepted fluoride content, can produce fluorosis of the teeth. A mother and her four children affected by this disorder presented different degrees of fluorosis directly related to the stage at which hormonal therapy was introduced.

Odontodysplasia. Report of two cases and review of the literature.

Odontodysplasia is a rare developmental anomaly affecting the tooth structures in both deciduous and permanent dentitions. The enamel is thin and uneven in thickness, and the detinal tissue surrounds very large pulp chambers. Denticles are present in the pulp organ. The maxilla is involved twice as frequently as the mandible. Most of the affected teeth are in the anterior segments; however, all other teeth can be affected. The cause is unknown. Because of the tendency of the affected teeth to develop abscesses, the most common treatment is extraction. Two additional cases are reported, and the literature is reviewed.

Image- and model-based surgical planning in otolaryngology.

Preoperative evaluation of any operating field is essential for the preparation of surgical procedures. The relationship between pathology and adjacent structures, and anatomically dangerous sites need to be analyzed for the determination of intraoperative action. For the simulation of surgery using three-dimensional imaging or individually manufactured plastic patient models, the authors have worked out different procedures. A total of 481 surgical interventions in the maxillofacial region, paranasal sinuses, orbit, and the anterior and middle skull base, in addition to neurotologic procedures were presurgically simulated using three-dimensional imaging and image manipulation. An intraoperative simulation device, part of the Aachen Computer-Assisted Surgery System, had been applied in 407 of these cases. In seven patients, stereolithography was used to create plastic patient models for the preparation of reconstructive surgery and prostheses fabrication. The disadvantages of this process include time and cost; however, the advantages included (1) a better understanding of the anatomic relationships, (2) the feasibility of presurgical simulation of the prevailing procedure, (3) an improved intraoperative localization accuracy, (4) prostheses fabrication in reconstructive procedures with an approach to more accuracy, (5) permanent recordings for future requirements or reconstructions, and (6) improved residency education.

Differential insertion of insulin receptor complexes into Triton X-114 bilayer membranes. Evidence for a differential accessibility of the membrane-exposed receptor domain.

In the present study, the Triton X-114 phase-separation system has been used to characterize molecular properties of the membrane-exposed domain of an integral-membrane hormone receptor. This approach provides novel details of the structure/function relationship of insulin receptors. Upon raising the temperature of a micellar Triton X-114 solution above the cloud-point, a detergent enriched phase pellets and coprecipitates 95% of the purified insulin-free (alpha beta)2 receptors. In contrast, 83% of the hormone bound (alpha beta)2 receptor complexes prefer the detergent-depleted phase, exhibiting prominent properties of non-membraneous proteins. Kinetic studies show that, following insulin binding, the amphiphilicity of the receptor complexes is immediately altered. Only monodisperse (alpha beta)2 complexes were detected when receptor/insulin complexes of the detergent-depleted phase were analyzed by detergent-free sucrose density centrifugation in the presence of 10 nM insulin. These results can be explained in the light of the lipid-bilayer-like organization of the precipitating Triton X-114; hormone-induced intramolecular alterations of (alpha beta)2 receptors appear to fundamentally restrict access to the membrane-exposed receptor domain. Basically, different molecular properties are found for alpha beta receptors. Only 67% of the insulin-free receptors coprecipitate with the Triton-X-114-enriched phase; following insulin binding the coprecipitation is only decreased to 42%. In contrast to (alpha beta)2 receptors, formation of noncovalently aggregated receptor complexes, which are detected by sucrose density centrifugation, could account for the exclusion of alpha beta receptor species from Triton X-114 membranes.

[Osteogenesis imperfecta Type 1: a case presentation with a new mutation in gene COL1A1]. / Osteogenesis imperfecta Typ 1: Fallbericht mit bis dato nicht beschriebener Mutation im COL1A1-Gen.

In a 4 year old girl the diagnosis osteogenesis imperfecta type I was suspected by following clinical criteria: four fractures after small trauma, intensive blue sclera, anomalies of dental enamel, macrocephalie with frontal bassing. Clinical diagnosis could be verified by moleculargenetic analysis, a newly recognized heterozygous point mutation (Arg420Stop) in the COL1A1-gene was found.

Assessment of children's anxiety throughout dental treatment by their drawings.

The handling of anxiety is of paramount importance during dental treatment of children. A simple and convenient method to measure this anxiety is based upon children's color drawings, prior and during the treatment course. One hundred and ninety-two drawings were done by fifty-five children, aged six to seven years, of whom forty-five children completed a full course of treatment. Their clinical behavior was also assessed and recorded. A combined analysis of the drawings and the clinical behavior pointed at an increase of anxiety after the first treatment session and a decline after the second one. After completion of treatment the rating of the children's behavior became similar to that of the initial visit; however, manifest anxiety was still expressed in their drawings. The analysis of the Dental Anxiety Scale (DAS) proved to be a sensitive and simple method for the pedodontist.

Stimulation characteristics of a steroid-eluting electrode compared with three conventional electrodes.

Stimulation thresholds of a steroid-eluting electrode (Medtronic CapSure 4003, 9 patients) were compared with three conventional electrodes (carbon-tipped lead, Siemens-Elema 423 S/60, 10 patients; Elgiloy-tipped lead, Cordis Encor, 10 patients; platinum-tipped lead, Telectronix Laserdish 030-276, 9 patients). Voltage thresholds were determined during implantation, 1-3 days, 6 weeks, and 6 months postimplantation. No significant difference among the four electrodes was found in regard to stimulation and sensing behavior during implantation. Compared to intraoperative measurements, mean increase in voltage threshold and absolute voltage thresholds were substantially less for the steroid-eluting electrode than for the other tested electrodes 6 weeks and 6 months after implantation. The rheobasechronaxie product, a parameter of the stimulation performance of electrodes, underlined the superior pacing characteristics of the steroid-eluting electrode. To achieve low chronic stimulation threshold by pharmacological means is an attractive direction for future electrode technology.

Assessment of a 2 percent buffered glutaraldehyde solution in pulpotomized primary teeth of schoolchildren.

This investigation was undertaken, clinically and radiographically, to assess the effect of glutaraldehyde as a pulp medicament in pulpotomized cariously exposed primary molars. Fifty-three primary molars of thirty-two second-grade children were evaluated after being treated by pulpotomy utilizing a 2 percent buffered glutaraldehyde solution. Failures were observed in 5.7 percent of the teeth at the six-month evaluation and increased with time: 9.6 percent after 12 months; and 18 percent after 25 months. Internal resorption was observed in six teeth; external resorption was found in only one tooth. Pulp canal obliteration, which was not listed as a failure, was observed in one tooth after 6 months, yielding a total of twenty teeth at the final examination. In thirty-eight pulpotomized teeth (82.6 percent), the resorption rate was similar to their antimeres; in another seven, root resorption was faster; and only one pulpotomized tooth resorbed more slowly than its antimere. The relatively high failure rate in the present study does not justify recommending a 2 percent buffered glutaraldehyde solution as a substitute to formocresol.