Canalith repositioning maneuver is effective to treat benign paroxysmal positional vertigo(BPPV). This case showed complicated form of the BPPV such as changes of canalolithiasis to cupulolithiasis, involvement of one canal to two canals and from unilateral to bilateral involvement during the reposition maneuver. This patient was diagnosed as left lateral canalolithiasis at first. After left barbecue maneuver, the type was changed to the right posterior cupulolithiasis. Semont maneuver was performed and then the type of BPPV was changed to combined type with right posterior canalolithiasis and left lateral canalolithiasis. We performed left barbecue maneuver and right Epley maneuver. Then the type of BPPV was changed to left lateral cupulolithiasis. After Brandt-Daroff maneuver and left barbecue maneuver, nystagmus and dizziness disappeared finally.
Dizziness ; Humans

The Graf system has supposed advantages with its flexible nature, as compared with rigid fixation. But there have been no reports about effects in the adjacent motion segment after soft stabilization. The purpose of this study was to evaluate the radiologic changes occuring in the adjacent segments of the Graf system and to assess its ability stabilizing the lumbar spine. A retrospective review of radiographs and medical records was undertaken in 32 cases who had been treated with the Graf system in degenerative lumbar spinal disorders. The average age at operation was 52.5 years and the average follow up period was 49.6 months. The results of this study were as follows: clinical assesments based on the Kirkaldy-Willis criteria revealed excellent in 13 cases (40.6%), good in 16 cases (50%), fair in 2 cases (6.3%) and poor in 1 case (3.1%). Radiologically we analysed the adjacent segments in 25 cases except the cases which did not have the correspondence between the clinical findings and the radiological findings, and the fixated segments in 32 cases. The acceleration of degenerative changes were found in the above adjacent segments in 11 cases (44%) and in the below adjacent segments in 5 cases (27.7%). Also, those changes were found in the fixated segments with discectomy in 19 cases (50%) and in the fixated segments without discectomy in 9 cases (37.5%). In conclusion, we think that the Graf system in a lumbar region may biomechanically influence the adjacent segments. The mechanical effects of the device could be changed by the polyester bands which were followed for a longer period of time in the fixated segments. Therefore, randomized prospective studies comparing the Graf system to other treatement methods could provide clear indications for lumbar spinal disorders.
Acceleration ; Diskectomy ; Equidae ; Follow-Up Studies ; Lumbosacral Region ; Medical Records ; Polyesters ; Retrospective Studies ; Spine

PURPOSE: To analyze the radiologic findings of facial nerve schwannoma. MATERIALS AND METHODS: The authors retrospectively reviewed CT and/or MR images and clinical history of eight patients with histologically provenfacial nerve schwannoma. After classifying this extratemporal and intratemporal types, clinical and radiologic findings were analysed. RESULTS: The most common clinical findings of facial nerve schwannoma were facial nervepalsy and hearing impairment in an intratemporal schwannoma(4/5), and a palpable parotid mass in an extratemporal schwannoma(3/3). On CT, each involved segment of intratemporal schwannomas(five cases) showed characteristic radiologic findings, while extratemporal schwannomas(three cases) showed masses of various types. On MRI, all tumors(two cases) showed hypointensity on T1WI, hyperintensity on T2WI, and strong enhancement on Gd-DTPA enhanced T1WI. CONCLUSION: Intratemporal facial nerve schwannomas can be easily diagnosed by characteristic clinical and radiologic findings. Extratemporal facial nerve schwannomas show nonspecific findings. However, if the tumor islocated between the superficial and the deep lobe of the parotid gland and extends to the posterior portion of thestyloid process, then facial nerve schwannoma is strongly suspected.
Facial Nerve* ; Gadolinium DTPA ; Hearing Loss ; Humans ; Magnetic Resonance Imaging ; Neurilemmoma* ; Parotid Gland

Granular cell tumors are rare lesions of probable Schwann cell origin and are composed of oval to fusiform cells with abundant granular eosinophilic cytoplasm. We report ultrasonography, barium enema, computed tomography and magnetic resonance imaging findings in a case of granuar cell tumor in the presacral space in a 34-year-old woman.
Barium ; Cytoplasm ; Enema ; Eosinophils ; Granular Cell Tumor* ; Magnetic Resonance Imaging ; Ultrasonography

The major influencing factors on the strength of all-ceramic crowns are types of dental ceramics, fabrication techniques, methods of abutment preparation and cementation modes of all ceramic restorations. Zine phosphate cement and glass-ionomer cement were used as an early luting media for all-ceramic crowns. Recently many studies have reported that resin cements have more advantages in increasing the fracture strength of restorations comparing with zincphosphate cement and glass-ionomer cement. The purpose of this study is to investigate the effect of etching, silane treatment, sandblasting and dentin bonding agents on fracture strengths of dental ceramics. 40 flat dentin specimens and 40 ceramic discs of 1.5mm thickness and 8mm diameter were fabricated, and divided into 4 groups according to surface treatments. Surface treatments before cementation were as follows. Group I : (ceramic) : HF etching - silane treatment - application of bonding resin (dentin) : application of dentin bonding agent Group II : (ceramic) : sandblasting - application of bonding resin (dentin) : application of dentin bonding agent Group III : (ceramic) : application of bonding resin (dentin) : application of dentin bonding agent Group IV : (ceramic) : HF etching - silane treatment - application of bonding resin (dentin) : no dentin bonding procedure Dentin specimens and ceramic discs were cemented with dual cure resin cement, and went through thermocycling. Compressive stress es were loaded on the centers of ceramic discs with Instron testing machine, and fracture strengths resista' nce for catastrophic fracture were measured The results were as follows. 1. The group I showed the highest fracture resistance. The next was group II. And group III, IV followed. 2. There was a significant difference in the mean value of fracture strengths between group I and group III (p<0.05), but no significant differences between group I and group II, and group II and group III (p>0.05). 3. There was a significant difference in the mean value of fracture strengths between group I and group IV (p<0.05).
Cementation ; Ceramics* ; Crowns ; Dentin ; Dentin-Bonding Agents ; Glass Ionomer Cements ; Resin Cements

No abstract available.
Carcinoma, Renal Cell*

Dental restorative materials must have the physical properties to withstand wear and corrosion. Base metal alloys possess better mechanical properties and lower price than the gold alloys. For these reason such alloys have largely replaced the precious metal alloys. One aspect to consider is the release of metal substances to oral environment. The release of elements from dental alloys is a continuing concern because the elements may have the potentially harmful biological effects on local tissue. The purpose of this study was to minimize metal release on the nonprecious metal surfaces by ion bea assisted deposition(IBAD) of titanium nitride (TiN). Ni-Cr-Be alloys with and without TiN coatings were secured in an wear test machine opposing ruby ball to determine their relative resistance to wear with 100m, 200m, 300m and 400m sliding distance. And the corrosion behavior of the Ni-Cr-Be alloys with and without TiN coating and 3 dental noble alloys have been studied. Potentiodynamic curves were used to analyse the corrosion characteristics of the alloys. The measurement of the released Ni and Ci ions was conducted by analysis of the electrolyte solution with atomic absorption spectroscopy. The results were as follows : 1. The critical sliding distance that wore down TiN coating of 2.5micrometer thickness in this study condition was 300m. 2. Ion beam assisted deposition of TiN showed a good surface modification with respect to the properties of wear and corrosion resistance. 3. X-ray diffraction showed that the strongest peak of TiN(111) in the coatings. 4. The release of Ni and Cr ions from alloys measured by means of atomic absorption spectroscopy was reduced by ion beam assisted deposition of TiN.
Absorption ; Alloys* ; Corrosion ; Dental Alloys ; Gold Alloys ; Ions ; Spectrum Analysis ; Tin* ; Titanium ; X-Ray Diffraction

The success of porcelain laminate veneer depends on the bond strength between tooth structure and ceramic restoration and the design of tooth preparation. In particular, incisal coverage and incisal finish line are the two most important factors in long-term fracture resistance. Although the majority of clinicians are practicing incisal coverage and there are various opinions on the geometrical ratio between the clinical crown length of the remaining tooth structure and the length of incisal extension in porcelain laminate veneer and the optimal incisal finish lines, scientific evidence still leaves much to be desired. The purpose of this study was to determine the effects of the amounts of incisal coverage and the types of incisal finish line on th stress distribution in maxillary anterior porcelain laminate veneers under two different loading conditions. Three-dimensional finite element models of a maxillary anterior porcelain veneer with different amounts of incisal coverage ; 0, 1, 2, and 3mm and different incisal finish lines ; feathered edge, incisal bevel, reverse bevel and lingual chamfer with various amounts of lingual extension were developed. 300N force was applied at the point 0.5mm cervical of the linguoincisal edge in two loading conditions ; A) 125 degrees, B) 132 degrees. tensile and compressive stress in ceramic and shear stress in the resin cement layer wee analyzed using three-dimensional finite element method. The results were as follows : 1. The types of incisal finish line had more influence on the stress distribution in porcelain laminate veneer than the amounts of incisal coverage. 2. In case of no incisal coverage, incisal beveled laminate exhibited more evenly distributed tensile stress than feathered edged laminate. And in case of incisal coverage, reverse beveled laminate and lingual chamfered laminate with 1mm lingual extension exhibited more evenly distributed tensile stress than lingual chamfered laminates with 2 mm and 3mm lingual extension. 3. As long as the lingual chamfer goes, less tensile stress was found at the incisal edge, while much more tensile stress was found at the lingual margin area in proportion to length of lingual extension. 4. Under 125 degree load, tensile stress in porcelain laminate veneer had increased compared with that under 132 degree load and the difference exhibited by the change of the amount of tooth support was larger. 5. The types of incisal finish line and the distance from the incisal finish line to the loading point had more influence on the shear stress distribution in the resin cement layer than the amount of incisal coverage. In contrast loading condition had little influence.
Animals ; Ceramics ; Crowns ; Dental Porcelain* ; Feathers ; Finite Element Analysis* ; Resin Cements ; Tooth ; Tooth Preparation

Dental practice can produce and spread some infetious diseases from patients to dentist, dental assistant, and dental labors. One possible method for preventing these cross-contamination is to immerse dental impression in chemical disinfectants. So far many investigators studied on the dimensional changes of dental impressions and on the surface qualities of stone casts made from impression following immersion in disinfectants. This study was proposed to evaluate some popular impression/disinfectant combination from the point of dimensional stability. Impression was taken from dental arch-shaped metal model. Irreversible hydrocolloid and 3 elastomers(polyvinyl siloxane, polysulfide, polyether) were immersed in 3 disinfectants (2% glutaraldehyde, 1% povidone-iodine, 0.5% sodium hypochlorite) for 10 minutes and measured both cross-arch and anterior-posterior distance under stereo microscope to evaluate dimensional change. The results obtained were as follows: 1. Dimensional changes of irreversible hydrocolloid impression was statistically different in crossarch and anterior-posterior distance when immersed in 2% glutaraldehyde solution and in anterior-posterior distance when immersed in 0.5% sodium hypochlorite solution from control group(p<0.05). 2. Dimensional changes of polyvinyl siloxane and polysulfide impression were not statistically different from control group (p>0.05). 3. Dimensional changes of polyether impression was statistically different in cross-arch distance when immersed in 0.5% sodium hypochlorite solution and in anterior-posterior distance when immersed in 1% povidone-iodine solution from control group (p<0.05). 4. In all cases, dimensional changes were less than 0.1% from the original dimension and concluded clinically acceptable
Colloids ; Dental Assistants ; Dentists ; Disinfectants ; Disinfection* ; Glutaral ; Humans ; Immersion* ; Polyvinyls ; Povidone-Iodine ; Research Personnel ; Siloxanes ; Sodium ; Sodium Hypochlorite

Periductal mastitis arises from major ducts. Radiographic reports describing the phases of duct ectasia and secretory calcifications, have been published, but descriptions of the phases of periductal mastitis are rare. We report the mammographic and ultrasonographic findings of periductal mastitis in a 30-year-old woman who presented with a breast lump.
Adult ; Breast ; Dilatation, Pathologic ; Female ; Humans ; Mastitis* ; Ultrasonography*