STATEMENT OF PROBLEM: One of the common problems of dental implant prosthesis is the loosening of the screw that connects each component, and this problem is more common in single implant-supported prostheses with external connection, and in molars. PURPOSE: The purposes of this study were: (1) to compare the initial abutment screw detorque values of the six different implant-abutment interface designs, (2) to compare the detorque values of the six different implant-abutment interface designs after cyclic loading, (3) to compare the detorque values of regular and wide diameter implants and (4) to compare the initial detorque values with the detorque values after cyclic loading. MATERIAL AND METHODS: Six different implant-abutment connection systems were used. The cement retained abutment and titanium screw of each system were assembled and tightened to 32Ncmwith digital torque gauge. After 10 minutes, initial detorque values were measured. The custom titanium crown were cemented temporarily and a cyclic sine curve load(20 to 320N, 14Hz) was applied. The detorque values were measured after cyclic loading of one million times by loading machine. One-way ANOVA test, scheffe's test and Mann-Whitney U test were used. RESULTS: The results were as follows : 1. The initial detorque values of six different implant-abutment connections were not significantly different(p> 0.05). 2. The detorque values after one million dynamic cyclic loading were significantly different (p <0.05). 3. The SS-II regular and wide implant both recorded the higher detorque values than other groups after cyclic loading(p <0.05). 4. Of the wide implants, the initial detorque values of Avana Self Tapping Implant, MIS and Tapered Screw Vent, and the detorque values of MIS implant after cyclic loading were higher than their regular counterparts(p <0.05). 5. After cyclic loading, SS-II regular and wide implants showed higher detorque values than before(p <0.05).
Crowns ; Dental Implants ; Molar ; Prostheses and Implants ; Titanium ; Torque

STATEMENT OF PROBLEM: The cast abutment has advantages of overcoming angulation problem and esthetic problem. However, when a gold-machined UCLA abutment undergoes casting, the abutment surfaces in contact with the implant may change. PURPOSE: The purpose of this study was to compare the detorque values of prefabricated machined abutments with gold-premachined cast-on UCLA abutments before and after casting in two types of internal implant-abutment connection systems: (1) internal hexagonal joint, (2) internal octagonal joint. Furthermore, the detorque values of two implant-abutment connection systems were compared. MATERIALS AND METHODS: Twenty internal hexagonal implants with an 11-degree taper and twenty internal octagonal implants with an 8-degree taper were acquired. Ten prefabricated titanium abutments and ten gold-premachined UCLA abutments were used for each systems. Each abutment was torqued to 30 Ncm according to the manufacturer's instructions and detorque value was recorded. The detorque values were measured once more, after casting with gold alloy for UCLA abutment, and preparation for titanium abutments. Group means were calculated and compared using independent t-test and paired t-test (alpha=0.05). RESULTS: The results were as follows: 1. The detorque values between titanium abutments and UCLA-type abutments showed significant differences in internal octagonal implants (P<0.05), not in internal hexagonal implants (P>0.05). 2. In comparison of internal hexagonal and octagonal implants, the detorque values of titanium abutments had significant differences between two connection systems on the initial analysis (P<0.05), not on the second analysis (P>0.05) and the detorque values of UCLA-type abutments were not significantly different between two connection systems (P>0.05). 3. The detorque values of titanium abutments and UCLA-type abutments decreased significantly on the second analysis than the initial analysis in internal hexagonal implants (P<0.05), not in internal octagonal implants (P>0.05). CONCLUSION: Casting procedures of UCLA-type abutments had no significant effect on screw loosening in internal implant-abutment connection systems, and UCLA-type abutments showed higher detorque values than titanium abutments in internal octagonal implants.
Alloys ; Joints ; Titanium

Multiple carcinoid tumors in stomach are very rare tumors and associated with pernicious anemia, chronic atrophic gastritis and Zollinger-Ellison syndrome. These are believed to be due to hypergastrinemia, resulting in chronic stimulation of enterochromaffine-like (ECL) cells, leading to hyperplasia, metaplasia and ultimately neoplasia. The carcinoid tumor is potentially malignant, even though it may grow slowly, so the treatment of choice must be endoscopic lumpectomy or surgical gastrectomy. The prognosis depends on the site of the tumor and its size. Most carcinoid tumors are less than 1 cm in size and metastasis is uncommon but metastasis in tumors with size over 2 cm is common. A case of multiple carcinoid tumors in stomach, which was successfully removed by endoscopy, is herein reported.
Anemia, Pernicious ; Carcinoid Tumor* ; Endoscopy ; Gastrectomy ; Gastrins ; Gastritis, Atrophic ; Hyperplasia ; Mastectomy, Segmental ; Metaplasia ; Neoplasm Metastasis ; Prognosis ; Stomach* ; Zollinger-Ellison Syndrome

BACKGROUND: Human adipose tissue is routinely discarded as medical waste. However, this tissue may have valuable clinical applications since methods have been devised to effectively isolate adipose-derived extracellular matrix (ECM), growth factors (GFs), and stem cells. In this review, we analyze the literature that devised these methods and then suggest an optimal method based on their characterization results. METHODS: Methods that we analyze in this article include: extraction of adipose tissue, decellularization, confirmation of decellularization, identification of residual active ingredients (ECM, GFs, and cells), removal of immunogens, and comparing structural/physiological/biochemical characteristics of active ingredients. RESULTS: Human adipose ECMs are composed of collagen type I–VII, laminin, fibronectin, elastin, and glycosaminoglycan (GAG). GFs immobilized in GAG include basic fibroblast growth factor (bFGF), transforming growth factor beta 1(TGF-b1), insulin like growth factor 1 (IGF-1), vascular endothelial growth factor (VEGF), platelet-derived growth factor (PDGF), BMP4 (bone morphogenetic protein 4), nerve growth factor (NGF), hepatocyte growth factor (HGF), and epithermal growth factor (EGF). Stem cells in the stromal-vascular fraction display mesenchymal markers, self-renewal gene expression, and multi-differentiation potential. CONCLUSION: Depending on the preparation method, the volume, biological activity, and physical properties of ECM, GFs, and adipose tissue-derived cells can vary. Thus, the optimal preparation method is dependent on the intended application of the adipose tissue-derived products.
Adipose Tissue ; Collagen ; Elastin ; Extracellular Matrix ; Fibroblast Growth Factor 2 ; Fibronectins ; Gene Expression ; Hepatocyte Growth Factor ; Humans ; Insulin ; Intercellular Signaling Peptides and Proteins ; Laminin ; Medical Waste ; Methods ; Nerve Growth Factor ; Platelet-Derived Growth Factor ; Stem Cells ; Transforming Growth Factor beta ; Vascular Endothelial Growth Factor A

OBJECTIVE: Chest pain is one of the most common complaints in the emergency department (ED). Cardiac computed tomography angiography (CCTA) is a frequently used tool for the early triage of patients with low- to intermediate-risk acute chest pain. We present a study protocol for a multicenter prospective randomized controlled clinical trial testing the hypothesis that a low-dose CCTA protocol using prospective electrocardiogram (ECG)-triggering and limited-scan range can provide sufficient diagnostic safety for early triage of patients with acute chest pain. METHODS: The trial will include 681 younger adult (aged 20 to 55) patients visiting EDs of three academic hospitals for acute chest pain or equivalent symptoms who require further evaluation to rule out acute coronary syndrome. Participants will be randomly allocated to either low-dose or conventional CCTA protocol at a 2:1 ratio. The low-dose group will undergo CCTA with prospective ECG-triggering and restricted scan range from sub-carina to heart base. The conventional protocol group will undergo CCTA with retrospective ECG-gating covering the entire chest. Patient disposition is determined based on computed tomography findings and clinical progression and all patients are followed for a month. The primary objective is to prove that the chance of experiencing any hard event within 30 days after a negative low-dose CCTA is less than 1%. The secondary objectives are comparisons of the amount of radiation exposure, ED length of stay and overall cost. RESULTS AND CONCLUSION: Our low-dose protocol is readily applicable to current multi-detector computed tomography devices. If this study proves its safety and efficacy, dose-reduction without purchasing of expensive newer devices would be possible.
Acute Coronary Syndrome ; Adult ; Angiography* ; Chest Pain ; Coronary Angiography ; Electrocardiography ; Emergencies* ; Emergency Service, Hospital ; Heart ; Humans ; Length of Stay ; Prospective Studies ; Radiation Exposure ; Retrospective Studies ; Thorax ; Triage