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Stanley Von Hagen

Publications and source records attributed to Stanley Von Hagen.

5 recordsLinked to original sources

Injections in patients with osteoarthritis and other musculoskeletal disorders: use of synthetic injection models for teaching physiatry residents.

This study examined whether resident injection skills could be enhanced using synthetic injection models. A total of 30 physiatry residents underwent written and injection-model pretesting and posttesting. After randomization into injection-model and control groups, the experimental group trained by watching an instructional videotape and by using models that gave visual feedback on injection accuracy, whereas the control group studied technical aspects of injections. Immediately after patient injections, a blinded attending graded residents on the required level of verbal or manual assistance. The experimental group performed significantly better during patient injections as per first injection data (i.e., the scores obtained from performing a procedure for the first time on each particular body region; P = 0.013), total injection data (i.e., the mean scores obtained from performing all procedures on each particular body region; P = 0.017), and postrotation practical testing (P < 0.007) but not for didactic knowledge (postrotation written testing; P < 0.039). Data analysis by body region showed significant benefit only for occasionally performed patient injection procedures. The benefit was most evident in less experienced residents. Injection-model accuracy testing correlated with actual patient injections, both for first injections into each major body region (r = 0.52, P = 0.005) and for all injections (r = 0.55, P = 0.003). Consideration should be given for incorporating injection-model training into residency education, especially for residents with less injection experience and for occasionally performed procedures. The overall correlation between model practical testing and subsequent patient injection performance suggests that models can measure injection competence.

Clinical Competence↗

Changes in alveolar bone height and width following post-extraction ridge augmentation using a fixed bioabsorbable membrane and demineralized freeze-dried bone osteoinductive graft.

BACKGROUND: It has been shown that the amount of healed bone following guided bone regeneration (GBR) with demineralized freeze-dried bone allograft (DFDBA) and a bioabsorbable membrane is significantly less than the initial quantity. A study was designed to determine if the amount of GBR would be affected by using an osteoinductive DFDBA and bioabsorbable membrane and membrane stabilization. METHODS: Eleven extraction sites (10 patients) were treated with DFDBA and bioabsorbable membrane before placing endosseous implants. Standardized alveolar height and width measurements were taken after extraction, GBR, and 4 months postoperatively, at predetermined measurement points (sites midpoint and 3 mm mesial and distal from the midpoint) and classified as augmented (<1 mm increase of GBR height or width) or grafted (>1 mm increase). Five membranes were stabilized. RESULTS: Three mm from the crest, augmented points exhibited a complete loss of augmented width. There was also some loss of pre-GBR bone width (ranging from 4.7% to 20%) at augmented and grafted points. Five mm from the crest, augmented points lost 83.3% to 92.3% of augmented width and grafted points lost 12.9% to 18% of pre-GBR width. Loss of augmented height ranged from 93.5% to 100%. Augmented (except distal) and grafted measurement points lost 2.1% to 12% of pre-GBR height. Comparing tacked and non-tacked sites, the former manifested less loss of augmented bone width, the latter augmented bone height. CONCLUSIONS: Results indicate a complete loss of augmented width 3 mm from the crest and almost complete loss in height and width 5 mm from the crest. Membrane stabilization appeared beneficial.

Absorbable Implants↗

Management of traumatic hyphema.

Hyphema (blood in the anterior chamber) can occur after blunt or lacerating trauma, after intraocular surgery, spontaneously (e.g., in conditions such as rubeosis iridis, juvenile xanthogranuloma, iris melanoma, myotonic dystrophy, keratouveitis (e.g., herpes zoster), leukemia, hemophilia, von Willebrand disease, and in association with the use of substances that alter platelet or thrombin function (e.g., ethanol, aspirin, warfarin). The purpose of this review is to consider the management of hyphemas that occur after closed globe trauma. Complications of traumatic hyphema include increased intraocular pressure, peripheral anterior synechiae, optic atrophy, corneal bloodstaining, secondary hemorrhage, and accommodative impairment. The reported incidence of secondary anterior chamber hemorrhage, that is, rebleeding, in the setting of traumatic hyphema ranges from 0% to 38%. The risk of secondary hemorrhage may be higher in African-Americans than in whites. Secondary hemorrhage is generally thought to convey a worse visual prognosis, although the outcome may depend more directly on the size of the hyphema and the severity of associated ocular injuries. Some issues involved in managing a patient with hyphema are: use of various medications (e.g., cycloplegics, systemic or topical steroids, antifibrinolytic agents, analgesics, and antiglaucoma medications); the patient's activity level; use of a patch and shield; outpatient vs. inpatient management; and medical vs. surgical management. Special considerations obtain in managing children, patients with hemoglobin S, and patients with hemophilia. It is important to identify and treat associated ocular injuries, which often accompany traumatic hyphema. We consider each of these management issues and refer to the pertinent literature in formulating the following recommendations. We advise routine use of topical cycloplegics and corticosteroids, systemic antifibrinolytic agents or corticosteroids, and a rigid shield. We recommend activity restriction (quiet ambulation) and interdiction of non-steroidal anti-inflammatory agents. If there is no concern regarding compliance (with medication use or activity restrictions), follow-up, or increased risk for complications (e.g., history of sickle cell disease, hemophilia), outpatient management can be offered. Indications for surgical intervention include the presence of corneal blood staining or dangerously increased intraocular pressure despite maximum tolerated medical therapy, among others.

Adrenal Cortex Hormones↗

Effect of primer solvent and curing mode on dentin shear bond strength and interface morphology.

UNLABELLED: There is a need to study the main and interactive bonding effects of differences in solvent and curing mode used for adhesive monomers in dentin bonding systems. OBJECTIVE: Two solvents (acetone and ethanol) and curing methods (light cure, dual cure) were evaluated on their effects on bond strength and interfacial morphology. METHOD AND MATERIALS: The adhesives studied were based on two monomers, pyromellitate of glyceryl dimethacrylate (PMGDM) and 2-hydroxy ethyl methacrylate (HEMA). Four groups of eight teeth each were cut to expose planar dentin sections and treated with (a) light-cure system with acetone as solvent (LCA group); (b) light-cure system with ethanol as solvent (LCE group); (c) dual-cure system with acetone as solvent (DCA group); and (d) dual-cure system with ethanol as solvent (DCE group). The treated sections were tested for shear bond strength to composite discs and interfacial morphology. RESULTS: The mean (standard deviation) of shear bond strength values (MPa) for the different groups were: LCA: 11.8 (2.3); LCE: 12.7 (2.7); DCA: 24.9 (9.3); and DCE: 21.6 (9.6). All bonded sections were characterized by a similar hybrid layer, resin tags, and overall interfacial morphology. CONCLUSION: There was a significant difference in shear bond strength as a function of cure mode, but not of solvent. The mean bond strength was higher for dual-cure systems studied. Oxygen inhibition effects may account for the difference between light-cure and dual-cure types.

Acetone↗