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1.
Article in English | MEDLINE | ID: mdl-38839481

ABSTRACT

OBJECTIVES: To elucidate the imaging characteristics of the gubernaculum tract (GT) in patients with cleidocranial dysplasia (CCD) as visualized with computed tomography (CT). STUDY DESIGN: This was a retrospective analysis of the presence and shape of GTs of unerupted permanent teeth and supernumerary teeth on CT in 9 patients with CCD. RESULTS: The overall GT detection rate for unerupted permanent teeth was 83.5% (81/97), with no significant difference between permanent teeth without and with adjacent supernumerary teeth (P = .414). The overall GT detection rate for unerupted supernumerary teeth was 83.1% (49/59). Of the 156 total unerupted teeth analyzed, 83.3% (130/156) were judged to have GTs. No significant difference in detection rate of GTs was found between permanent and supernumerary teeth (P > 0.999). A composite morphology consisted of a single GT for a permanent unerupted tooth with 1 or 2 supernumerary teeth in which the dental follicles of the permanent and supernumerary teeth were confluent. In total, 44 groups consisted of 1 permanent and 1 or 2 supernumerary teeth; 79.5% (35/44) had GTs. CONCLUSIONS: A specific composite structure of GTs and dental follicles may signify that 2 or 3 teeth are derived from a single dental lamina in patients with CCD. In such cases, tooth eruption may fail due to the presence of only 1 GT for multiple teeth.

2.
JGH Open ; 8(6): e13077, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38835337

ABSTRACT

Background and Aim: Recently, noninvasive fecal markers have been used as indicators of intestinal inflammation in patients with inflammatory bowel disease (IBD). We conducted a clinical validation study to measure fecal calprotectin (Cp), lactoferrin (Lf), and hemoglobin (Hb) levels using an all-in-one kit in patients with IBD and colorectal tumors and aimed to clarify the utility of these fecal markers. Methods: In this study, 104 patients were analyzed, including 25 patients with ulcerative colitis (UC), 20 with Crohn's disease (CD), 48 with colorectal tumors, and 13 healthy controls (HC). Of the 48 patients with colorectal tumors, 14 had invasive cancer. We validated the utility of fecal Cp, Lf, and Hb levels by simultaneously measuring fecal markers in patients with IBD and colorectal tumors. Results: Fecal Cp and Lf had almost equivalent abilities in detecting clinical remission in patients with UC; however, fecal Cp was slightly superior to Lf. Regarding colorectal tumors, fecal Cp and Lf levels tended to be higher in patients with adenomas and colorectal cancer than in HCs. Although fecal Hb alone had the best sensitivity and specificity for detecting colorectal cancer, it had relatively low sensitivity for detecting advanced neoplasms and colorectal cancer. Conclusion: Fecal Cp and Lf can be used as almost equivalent biomarkers to assess the clinical activity in patients with UC. Fecal Hb is the most useful marker for screening colorectal cancer; however, adding fecal Cp and Lf may compensate for the low sensitivity of detecting for advanced colorectal tumors based on Hb alone.

3.
Article in English | MEDLINE | ID: mdl-38781496

ABSTRACT

OBJECTIVES: To elucidate the relationships between the maximum standardized uptake value (SUVmax) of alveolar bone and those of lymph nodes (LNs) around the neck on 18F-fluoro-2-deoxy-D-glucose (18F-FDG) positron emission tomography (PET). METHODS: The SUVmax values of alveolar bone and of level IA, level IB, and level IIA LNs of 174 patients, including those with and without active odontogenic inflammation, on PET/computed tomography (PET/CT) performed for a health check were retrospectively evaluated. The upper and lower jaws were divided into four blocks (right maxilla, left maxilla, right mandible, and left mandible). The SUVmax values of each block and of the LNs were calculated. The differences in the SUVmax of each LN level between patients with and without odontogenic inflammation, and the relationship between the SUVmax values of alveolar bone and of the LNs were analyzed statistically. RESULTS: Significant differences in SUVmax values of bilateral level IB and IIA LNs were found between patients with and without odontogenic inflammation (Mann-Whitney U test: right level IB, p = 0.008; left level IB, p = 0.006; right level IIA, p < 0.001; left level IIA, p = 0.002), but not in bilateral level IA LNs (Mann-Whitney U test: right level IA, p = 0.432; left level IA, p = 0.549). The inflammatory site with the highest SUVmax in level IB LNs was the ipsilateral mandible (multivariate analysis: right, beta = 0.398, p < 0.001; left, beta = 0.472, p < 0.001), and the highest SUVmax in level IIA LNs was the ipsilateral maxilla (multivariate analysis: right, beta = 0.223, p = 0.002; left, beta = 0.391, p < 0.001). CONCLUSIONS: The SUVmax values of level IB and IIA LNs were associated with a tendency toward a higher SUVmax value of alveolar bone on 18F-FDG-PET.

5.
Polymers (Basel) ; 16(5)2024 Feb 29.
Article in English | MEDLINE | ID: mdl-38475344

ABSTRACT

The objective of this study is to evaluate the impact of the thickness and translucency of various computer-aided design/computer-aided manufacturing (CAD/CAM) materials on the polymerization of dual-cure resin cement in endocrown restorations. Three commercially available CAD/CAM materials-lithium disilicate glass (e.max CAD), resin composite (CERASMART), and a polymer-infiltrated ceramic network (ENAMIC)-were cut into plates with five different thicknesses (1.5, 3.5, 5.5, 7.5, and 9.5 mm) in both high-translucency (HT) and low-translucency (LT) grades. Panavia V5, a commercial dual-cure resin cement, was polymerized through each plate by light irradiation. Post-polymerization treatment was performed by aging at 37 °C for 24 h under light-shielding conditions. The degree of conversion and Vickers hardness measurements were used to characterize the polymerization of the cement. The findings revealed a significant decrease in both the degree of conversion and Vickers hardness with increasing thickness across all CAD/CAM materials. Notably, while the differences in the degree of conversion and Vickers hardness between the HT and LT grades of each material were significant immediately after photoirradiation, these differences became smaller after post-polymerization treatment. Significant differences were observed between samples with a 1.5 mm thickness (conventional crowns) and those with a 5.5 mm or greater thickness (endocrowns), even after post-polymerization treatment. These results suggest that dual-cure resin cement in endocrown restorations undergoes insufficient polymerization.

6.
Tomography ; 10(2): 231-242, 2024 Feb 08.
Article in English | MEDLINE | ID: mdl-38393286

ABSTRACT

BACKGROUND: Since there are many differential diagnoses for cemento-osseous dysplasia (COD), it is very difficult for dentists to avoid misdiagnosis. In particular, if COD is related to an embedded tooth, differential diagnosis is difficult. However, there have been no reports on the characteristics of the imaging findings of COD associated with embedded teeth. The aim of the present study was to investigate the occurrence and imaging characteristics of cemento-osseous dysplasia (COD) associated with embedded teeth, in order to appropriately diagnose COD with embedded teeth. METHODS: The radiographs with or without histological findings of 225 patients with COD were retrospectively analyzed. A retrospective search through the picture archiving and communication system (PACS) of the Division of Oral and Maxillofacial Radiology of Kyushu Dental University Hospital was performed to identify patients with COD between 2011 and 2022. RESULTS: Fifteen COD-associated embedded mandibular third molars were identified in 13 patients. All 13 patients were asymptomatic. On imaging, COD associated with embedded mandibular third molars appeared as masses that included calcifications around the apex of the tooth. On panoramic tomography, COD showed inconspicuous internal calcification similar to that of odontogenic cysts or simple bone cysts, especially in patients with COD only around the mandibular third molar region. Those with prominent calcification resembled cemento-ossifying fibroma, calcifying epithelial odontogenic tumor, calcifying odontogenic cyst, adenomatoid odontogenic tumor, and so on, as categories of masses that include calcifications on panoramic tomography and computed tomography. CONCLUSIONS: The current investigation is the first to report and analyze the imaging characteristics of COD associated with embedded teeth. It is important to consider the differences between COD and other cystic lesions on panoramic tomography, and the differences between COD and masses that include calcifications on CT.


Subject(s)
Cementoma , Odontogenic Tumors , Humans , Retrospective Studies , Odontogenic Tumors/complications , Odontogenic Tumors/diagnostic imaging , Cementoma/diagnostic imaging , Cementoma/pathology , Radiography , Tomography, X-Ray Computed
7.
BMC Oral Health ; 24(1): 6, 2024 01 03.
Article in English | MEDLINE | ID: mdl-38172760

ABSTRACT

BACKGROUND: Very recently, a significant relationship between tonsilloliths and dental plaque-related pathologies was reported using digital panoramic radiographs. Their dynamics over time suggest that tonsilloliths may be in a permanently active phase that functions to remove foreign matter. The aim of the study was to evaluate the relationship between the occurrence of tonsilloliths and the extent of periodontitis. METHODS: A total of 608 patients who underwent both CT and panoramic radiographs were included in the study. Both of two imaging were retrospectively and independently assessed with respect to the presence of tonsilloliths detected on CT and panoramic radiographs, and bone defects caused by periodontitis detected on panoramic radiographs. The type of retrospective study is case-control. Then, the differences between age groups were evaluated with respect to the degree of bone resorption and its correlation with the presence of tonsilloliths. The relationships between categorical variables were assessed using Pearson's correlation coefficient or Spearman's correlation coefficient. RESULTS: There was a significant relationship between tonsilloliths on CT and the extent of the bone defect on panoramic radiographs (Spearman's correlation coefficient, r = 0.648, p = 0.043). In addition, there was a significant difference in the extent of the bone defect caused by periodontitis between subjects with and without tonsilloliths in the 60 to 69-year-old group (Mann-Whitney U test, p = 0.025), 70 to 79-year-old group (Mann-Whitney U test, p = 0.002), and 80 to 89-year-old group (Mann-Whitney U test, p = 0.022), but not in other age groups (Mann-Whitney U test: under 9-year-old group, p = 1.000; 10 to 19-year-old group, p = 1.000; 20 to 29-year-old group, p = 0.854; 30 to 39-year-old group, p = 0.191, 40 to 49-year-old group, p = 0.749; 50 to 59-year-old group, p = 0.627; ≥90-year-old group, p = 1.000). CONCLUSIONS: The presence of tonsilloliths was related to the extent of periodontitis because the structures were responding dynamically.


Subject(s)
Periodontitis , Pharyngeal Diseases , Humans , Middle Aged , Aged , Child , Adolescent , Young Adult , Adult , Aged, 80 and over , Retrospective Studies , Pilot Projects , Pharyngeal Diseases/epidemiology , Pharyngeal Diseases/pathology , Radiography, Panoramic , Periodontitis/complications , Periodontitis/diagnostic imaging
8.
Res Pract Thromb Haemost ; 8(1): 102284, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38268521

ABSTRACT

Background: Severe aortic stenosis (AS) causes acquired von Willebrand syndrome by the excessive shear stress-dependent cleavage of high molecular weight multimers of von Willebrand factor (VWF). While the current standard diagnostic method is so-called VWF multimer analysis that is western blotting under nonreducing conditions, it remains unclear whether a ratio of VWF Ristocetin co-factor activity (VWF:RCo) to VWF antigen levels (VWF:Ag) of <0.7, which can be measured with an automated coagulation analyzer in clinical laboratories and is used for the diagnosis of hereditary von Willebrand disease. Objectives: To evaluated whether the VWF:RCo/VWF:Ag is useful for the diagnosis of AS-induced acquired von Willebrand syndrome. Methods: VWF:RCo and VWF:Ag were evaluated with the VWF large multimer index as a reference, which represents the percentage of a patient's VWF high molecular weight multimer ratio to that of standard plasma in the VWF multimer analysis. Results: We analyzed 382 patients with AS having transaortic valve maximal pressure gradients of >30 mmHg, 27 patients with peripheral artery disease, and 46 control patients free of cardiovascular disease with osteoarthritis, diabetes, and so on. We assumed a large multimer index of <80% as loss of VWF large multimers since 59.0% of patients with severe AS had the indices of <80%, while no control patients or patients with peripheral artery disease, except for 2 patients, exhibited the indices of <80%. The VWF:RCo/VWF:Ag ratios, measured using an automated blood coagulation analyzer, were correlated with the indices (rs = 0.470, P < .001). When the ratio of <0.7 was used as a cut-off point, the sensitivity and specificity to VWF large multimer indices of <80% were 0.437 and 0.826, respectively. Conclusion: VWF:RCo/VWF:Ag ratios of <0.7 may indicate loss of VWF large multimers with high specificity, but low sensitivity. VWF:RCo/VWF:Ag ratios in patients with AS having a ratio of <0.7 may be useful for monitoring the loss of VWF large multimers during their clinical courses.

9.
Clin Gastroenterol Hepatol ; 22(2): 271-282.e3, 2024 02.
Article in English | MEDLINE | ID: mdl-37743040

ABSTRACT

BACKGROUND & AIMS: Reported rates of delayed bleeding (DB) after endoscopic resection using direct oral anticoagulants (DOACs) are high and heterogeneous. This large-scale multicenter study analyzed cases of DB after colorectal endoscopic submucosal dissection related to various types of DOACs in Japan (the ABCD-J study) with those associated with warfarin. METHODS: We retrospectively reviewed 1019 lesions in patients treated with DOACs and 459 lesions in patients treated with warfarin among 34,455 endoscopic submucosal dissection cases from 47 Japanese institutions between 2012 and 2021. The DB rate (DBR) with each DOAC was compared with that with warfarin. Risk factors for DB in patients treated with DOACs or warfarin were also investigated. RESULTS: The mean tumor sizes in the DOAC and warfarin groups were 29.6 ± 14.0 and 30.3 ± 16.4 mm, respectively. In the DOAC group, the DBR with dabigatran (18.26%) was significantly higher than that with apixaban (10.08%, P = .029), edoxaban (7.73%, P = .001), and rivaroxaban (7.21%, P < .001). Only rivaroxaban showed a significantly lower DBR than warfarin (11.76%, P = .033). In the multivariate analysis, heparin bridging therapy (odds ratio [OR], 2.18; 95% confidence interval [CI], 1.27-3.73, P = .005), rectal location (2.01, 1.28-3.16, P = .002), and procedure time ≥55 minutes (2.43, 1.49-3.95, P < .001) were significant risk factors for DB in the DOAC group. The DB risk in the DOAC group (OR, (95% CI)) was 2.13 (1.30-3.50) and 4.53 (2.52-8.15) for 1 and 2 significant risk factors, respectively. CONCLUSIONS: Dabigatran was associated with a higher DBR than other DOACs, and only rivaroxaban was associated with a significantly lower DBR than warfarin.


Subject(s)
Atrial Fibrillation , Colorectal Neoplasms , Endoscopic Mucosal Resection , Humans , Warfarin , Rivaroxaban/adverse effects , Dabigatran/adverse effects , Japan , Endoscopic Mucosal Resection/adverse effects , Retrospective Studies , Hemorrhage/chemically induced , Anticoagulants , Colorectal Neoplasms/surgery , Colorectal Neoplasms/complications , Administration, Oral , Atrial Fibrillation/complications
11.
Intern Med ; 62(14): 2059-2062, 2023 Jul 15.
Article in English | MEDLINE | ID: mdl-36418102

ABSTRACT

Heyde's syndrome is a disease in which patients with aortic stenosis (AS) bleed from angiodysplasia. An 80-year-old woman with a history of severe AS was referred to our hospital with melena and anemia. The patient underwent jejunal resection after repeated blood transfusions. A pathological examination revealed angiodysplasia, and the patient's plasma lacked high-molecular-weight von Willebrand factor (VWF) multimers, leading to the diagnosis of Heyde's syndrome. The patient underwent transcatheter aortic valve implantation (TAVI) one year after the diagnosis, and the VWF index recovered. This is a valuable case in which the pathological analysis of angiodysplasia associated with Heyde's syndrome was possible.


Subject(s)
Angiodysplasia , Aortic Valve Stenosis , Colonic Diseases , Transcatheter Aortic Valve Replacement , von Willebrand Diseases , Female , Humans , Aged , Aged, 80 and over , von Willebrand Factor , Gastrointestinal Hemorrhage/diagnosis , Aortic Valve Stenosis/complications , Aortic Valve Stenosis/surgery , Transcatheter Aortic Valve Replacement/adverse effects , Colonic Diseases/complications , Angiodysplasia/complications , Angiodysplasia/diagnosis , von Willebrand Diseases/complications , von Willebrand Diseases/diagnosis
13.
Clin J Gastroenterol ; 16(1): 73-80, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36414888

ABSTRACT

Patients with various cancers benefit from immune checkpoint inhibitors. However, immune checkpoint inhibitor-induced adverse events have also been reported, such as colitis. Prednisolone is the first-line treatment for immune-related adverse events, but second-line therapy for patients refractory to steroids has not been established. Furthermore, the inflammatory cytokine expression pattern in the intestinal mucosa of patients with steroid-refractory immune-related colitis remains unclear. We present the case of a 48-year-old man diagnosed with immune-related colitis and pancreatitis induced by pembrolizumab for advanced lung cancer. First, we administered 50 mg/day of prednisolone, and the patient's abdominal symptoms improved. However, the pancreatic enzyme levels did not return to normal. Furthermore, the patient's diarrhea worsened and hematochezia appeared at a 40 mg/day prednisolone dose. A mucosal cytokine analysis identified a low interleukin-10 messenger RNA level, which has been associated with a poor response to prednisolone. Thus, we administered 5 mg/kg of infliximab; the patient's diarrhea and hematochezia immediately improved, and the pancreatic enzyme levels returned to normal. Infliximab was administered three times every 2 weeks. After, the patient's colitis and pancreatitis did not recur. To our knowledge, this is the first report demonstrating the effectiveness of infliximab for immune-related colitis and pancreatitis.


Subject(s)
Colitis , Pancreatitis , Male , Humans , Middle Aged , Infliximab/adverse effects , Neoplasm Recurrence, Local/drug therapy , Colitis/chemically induced , Colitis/drug therapy , Prednisolone/therapeutic use , Cytokines/adverse effects , Diarrhea/chemically induced , Diarrhea/drug therapy , Pancreatitis/chemically induced
14.
Clin J Gastroenterol ; 16(2): 187-192, 2023 Apr.
Article in English | MEDLINE | ID: mdl-36417106

ABSTRACT

A 77-year-old patient with ulcerative colitis (UC) was transferred to our department because of worsening bloody diarrhea and abdominal pain, which was consistent with a UC flare. Two days after admission, she complained of cough and high fever. The polymerase chain reaction (PCR) test for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was positive, and a computed tomography showed pneumonia in the left lobe, consistent with coronavirus disease 2019 (COVID-19) pneumonia. However, frequent bloody diarrhea and abdominal pain due to the UC flare persisted; therefore, an additional immunosuppressive agent needed to be considered. We initiated infliximab biosimilar (IFX-BS), and her abdominal symptoms improved. However, they deteriorated after the second IFX-BS infusion. After confirming that the patient was negative for SARS-CoV-2 by PCR, we administered a combination of azathioprine and IFX-BS. The combination treatment improved her intestinal symptoms without worsening COVID-19 pneumonia. She has remained in remission for over a year since her discharge.


Subject(s)
COVID-19 , Colitis, Ulcerative , Pneumonia , Female , Humans , Aged , Colitis, Ulcerative/complications , Colitis, Ulcerative/drug therapy , Azathioprine/therapeutic use , COVID-19/complications , SARS-CoV-2 , Infliximab/therapeutic use
15.
DEN Open ; 3(1): e123, 2023 Apr.
Article in English | MEDLINE | ID: mdl-36247311

ABSTRACT

Objectives: Endoscopic resection (ER) is a minimally invasive treatment for early gastric cancer (EGC); however, there is a high occurrence of bleeding. This study aimed to clarify the significance of red blood cell distribution width (RDW) as a predictive risk factor for bleeding after ER for EGC. Methods: We conducted a retrospective study based on data for patients who underwent ER for EGC from 2019 to 2021. This study included 79 lesions in 54 patients who underwent ER for EGC. The primary outcome was the association between RDW before ER and bleeding within 28 days of treatment. Receiver operating characteristic (ROC) curves were constructed, wherein areas under the curve (AUCs) and 95% confidence intervals were calculated to compare the discriminatory power of RDW for predicting bleeding. Results: Endoscopic submucosal dissection was used as the resection method for 73 lesions, whereas endoscopic mucosal resection was used for six lesions. En bloc resection was performed in all cases. There were no cases of perforation; however, bleeding after ER occurred in five cases (9.3%). ROC curve analysis of bleeding after ER showed that the AUC was 0.843 with a good diagnostic performance. When the cut-off value of RDW was set at 14.4%, sensitivity and specificity were 80% and 85.7%, respectively. There was a bleeding rate of 36.4% (4/11) at an RDW of ≥14.4%, which was significantly higher than that of 2.3% (1/43) at an RDW of <14.4%. Conclusion: RDW can be a predictor of bleeding risk after ER for EGC.

16.
Polymers (Basel) ; 14(19)2022 Sep 28.
Article in English | MEDLINE | ID: mdl-36236020

ABSTRACT

We evaluated the fracture strength and failure mode of non-ferrule teeth with flared root canals that were restored using new experimental sleeve composites. Fifty endodontically treated anterior teeth with flared root canals were restored with direct restorations utilizing different techniques. Group A had teeth (non-ferrule) restored using commercialized MI glass fiber post + Gradia Core as core build-up. Group B had teeth (non-ferrule) restored with commercialized i-TFC glass fiber post + sleeve system. In Group C, the teeth (non-ferrule) were restored with an experimental sleeve composite with commercialized MI glass fiber post and Gradia Core. Group D, teeth (non-ferrule), were restored using custom-made tapered E-glass filling post and Gradia Core. Group E, teeth (with ferrule), were restored with commercialized MI glass fiber post + Gradia Core. After core construction, all specimens underwent direct composite crown restoration and were loaded until fracture using a universal testing machine. Average fracture loads were compared, and the failure modes were observed. Group C exhibited significantly greater fracture strength than other groups (p < 0.05). Favorable fracture teeth ratio of group C was more than that of the other groups. Thus, the new experimental sleeve composite could be clinically useful for core construction of non-ferrule teeth.

17.
DEN Open ; 2(1): e42, 2022 Apr.
Article in English | MEDLINE | ID: mdl-35079746

ABSTRACT

Patients with coronavirus disease 2019 (COVID-19) primarily cause respiratory symptoms. However, gastrointestinal (GI) symptoms can also occur. The endoscopic characteristics of the GI tract in COVID-19 patients remain unclear. We herein report a 62-year-old male with severe COVID-19 who needed multidisciplinary treatment, including extracorporeal membrane oxygenation (ECMO). Despite the improvement in his respiratory status, GI bleeding developed. Capsule endoscopy and colonoscopy revealed extensive mucosal sloughing in the lower intestinal tract. Additionally, we performed a comprehensive analysis of the mRNA expression levels of various proinflammatory cytokines in the intestinal mucosal tissues. The results suggested a significant elevation of IL-6, which could be involved in the pathophysiology of the GI involvement in COVID-19. Further investigation with more clinical data, including endoscopic findings and molecular analyses, will contribute to a comprehensive understanding of COVID-19-associated GI injury.

18.
J Dent Sci ; 17(1): 42-48, 2022 Jan.
Article in English | MEDLINE | ID: mdl-34457200

ABSTRACT

BACKGROUND/PURPOSE: In Japan, medical and dental care is provided by the universal health insurance system. The Ministry of Health, Labour, and Welfare (MHLW) in Japan sets the rules for health care services provided by health insurance. The MHLW issued a notice in 2020 permitting telemedicine and dental telemedicine for the first visit and for follow-up visits to prevent the spread of COVID-19 infection. We conducted this study to clarify the status of dental telemedicine during 2020. MATERIALS AND METHODS: We used data from lists obtained on the MHLW website in the analysis. We investigated the number of dental institutions conducing dental telemedicine for the first visit and for follow-up visits by prefecture. RESULTS: In each prefecture, fewer dental institutions conducted telemedicine for the first visit than for follow-up visits. Regions with large metropolitan areas had higher numbers of dental institutions conducting dental telemedicine for the first visit and follow-up visits. Private dental clinics provided the largest proportion of dental telemedicine for the first visit, and general hospitals provided the largest proportion for follow-up visits. CONCLUSION: Our study findings indicated that many dental institutions in Japan made efforts to provide dental services via dental telemedicine using the telephone or online with video to help prevent the spread of COVID-19 infection. Dental telemedicine can help patients to access dental services and dental care, thereby expanding the potential of dental telemedicine in Japan.

19.
Materials (Basel) ; 14(23)2021 Dec 02.
Article in English | MEDLINE | ID: mdl-34885547

ABSTRACT

The preset shape and diameter of a prefabricated FRC post rarely follows the anatomy of the root canal. To solve this problem, a new hollow sleeve composite (HSC) system for post-core construction was developed and characterized. A woven fiber was impregnated with two types of resins: Bis-GMA or PMMA, and rolled into cylinders with outer diameter of 2 mm and two different inner diameters, namely 1.2 or 1.5 mm. The commercial i-TFC system was used as a control. Dual-cure resin composite was injected into these sleeves. Additionally, conventional solid fiber post was used as the inner part of the sleeve. The three-point bending test was used to measure the mechanical properties of the specimens and the fracture surface was examined using an electron microscope (SEM). The HSC (1.5 mm, Bis-GMA) revealed a statistically similar flexural modulus but higher flexural strength (437 MPa) compared to i-TFC (239 MPa; ANOVA, p < 0.05). When a fiber post was added inside, all values had a tendency to increase. After hydrothermal accelerated aging, the majority of specimens showed a significant (p < 0.05) decrease in flexural strength and modulus. SEM fracture analysis confirmed that the delamination occurred at the interface between the outer and inner materials. The HSC system provided flexibility but still high mechanical values compared to the commercial system. Thus, this system might offer an alternative practical option for direct post-core construction.

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