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1.
Cancer Diagn Progn ; 4(5): 611-616, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39238622

RESUMO

Background/Aim: Transarterial chemoembolization (TACE) is the standard treatment for patients with hepatocellular carcinoma in the intermediate stage; however, with advances in systemic therapy, the indications for TACE have gained significance. While lenvatinib (LEN)-TACE offers the potential for good outcomes, local recurrence has not yet been adequately investigated. Therefore, this study investigated local recurrence factors for each type of TACE, focusing on the lipiodol (Lip) value in LEN-TACE and conventional TACE. Patients and Methods: Fifty patients (50 nodes) with hepatocellular carcinoma and a tumor size <7 cm who underwent LEN-TACE or TACE between January 2022 and June 2023 were included in this study to investigate local recurrence and its influencing factors. Results: The local recurrence rate after LEN-TACE was 5.6% at 6 months and 11.5% at 12 months, whereas those after TACE were 6.4% at 6 months and 13.2% at 12 months (p=0.028). There were no significant differences in local recurrence rates according to background liver factors, alpha-fetoprotein (AFP), des-γ-carboxy prothrombin (DCP) values, sex, age, and albumin-bilirubin (ALBI) score. Lipiodol (Lip) values immediately after LEN-TACE were significantly higher than those after TACE alone (p=0.021). Multivariate analysis showed that LEN-TACE had a recurrence hazard ratio of 0.184. Conclusion: LEN-TACE provided good local tumor control. Local recurrence factors included LEN pretreatment, and Lip CT values were higher immediately after LEN-TACE. Thus, LEN-TACE after upfront LEN administration may increase the effectiveness of TACE.

3.
In Vivo ; 38(5): 2501-2505, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39187329

RESUMO

BACKGROUND/AIM: The prognosis of hepatocellular carcinoma (HCC) complicated with portal vein tumor thrombus (PVTT) is extremely poor. This study investigated whether local ablation-a curative treatment similar to resection-could improve the prognosis of patients with Child-Pugh B/C PVTT. PATIENTS AND METHODS: Between January 2020 and December 2023, 25 patients with Child-Pugh B/C PVTT HCC were enrolled, and their overall survival with radiofrequency ablation treatment and the associated drivers were investigated. RESULTS: Overall survival (median 282 days) differed between the group treated with transarterial chemoembolization (TACE, 285 days) and the group without it (159 days, p=0.0151). The median survival in the esophagogastric variceal exacerbation group (120.5 days) was shorter than that in the non-exacerbation group (284.0 days, p=0.00964). In multivariate analysis, concomitant TACE had a hazard ratio (HR) of 0.121 (p=0.0097), and the exacerbation of esophagogastric varices had a HR of 6.761 (p=0.01). CONCLUSION: Local ablation for PVTT may promote patient survival specifically by inhibiting the exacerbation of portal hypertension in patients with hepatocellular carcinoma.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Veia Porta , Humanos , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/complicações , Carcinoma Hepatocelular/cirurgia , Carcinoma Hepatocelular/terapia , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/complicações , Neoplasias Hepáticas/cirurgia , Neoplasias Hepáticas/terapia , Neoplasias Hepáticas/patologia , Masculino , Feminino , Veia Porta/patologia , Veia Porta/cirurgia , Pessoa de Meia-Idade , Idoso , Prognóstico , Trombose Venosa/mortalidade , Trombose Venosa/etiologia , Trombose Venosa/cirurgia , Trombose Venosa/terapia , Trombose Venosa/patologia , Resultado do Tratamento , Quimioembolização Terapêutica/métodos , Ablação por Radiofrequência/métodos , Ablação por Cateter/métodos , Adulto
4.
Intern Med ; 63(18): 2491-2497, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-38346734

RESUMO

Objective Nonalcoholic fatty liver disease/nonalcoholic steatohepatitis (NAFLD/NASH) treatment guidelines recommend sodium glucose cotransporter 2 inhibitor (SGLT2I) and glucagon-like peptide-1 agonist (GLP-1A) therapy in patients with type 2 diabetes mellitus (T2DM). SGLT2I improves the pathological condition of NAFLD/NASH in T2DM patients. However, cases of rebound during long-term SGLT2I treatment have been reported. This study investigated the efficacy of SGLT2I and GLP-1A combination therapy in diabetic patients with NAFLD by examining changes in computed tomography (CT)-based body composition and clinical outcomes. Methods Fifteen patients (5 men/10 women) with T2DM-associated NAFLD who had not responded to SGLT2I treatment and were being treated with GLP-1A combination therapy were included. Changes in the liver function, visceral adipose tissue index (VATI), and subcutaneous adipose tissue index (SATI) were compared using CT to evaluate the body composition. Results SGLT2I significantly improved alanine aminotransferase (28.0 to 13.0 IU/L), alkaline phosphatase (250.0 to 77.0 IU/L), and gamma glutamyl transpeptidase (23.0 to 12.0 IU/L) levels. The body mass index (BMI) decreased from 25.7 to 25.2 kg/m2. A CT-based analysis showed a significant improvement in SATI (80.9 to 66.1, p=0.002), with no significant change in VATI (53.2 to 51.5). GLP-1A addition improved the BMI (25.2 to 23.5 kg/m2) and hemoglobin A1c (6.5% to 6.2%, p=0.001). A further analysis revealed additional improvement in SATI (66.1 to 56.6, p=0.007) and a significant decrease in VATI (51.5 to 48.3, p=0.001). Conclusion SGLT2I and GLP-1A combination therapy improved the liver function, body composition, and glycemic control in diabetic patients with NAFLD/NASH, as well as SATI and VATI. The optimal timing of combination therapy remains to be determined.


Assuntos
Composição Corporal , Diabetes Mellitus Tipo 2 , Quimioterapia Combinada , Peptídeo 1 Semelhante ao Glucagon , Hepatopatia Gordurosa não Alcoólica , Inibidores do Transportador 2 de Sódio-Glicose , Humanos , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/complicações , Inibidores do Transportador 2 de Sódio-Glicose/uso terapêutico , Inibidores do Transportador 2 de Sódio-Glicose/administração & dosagem , Masculino , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/complicações , Feminino , Pessoa de Meia-Idade , Composição Corporal/efeitos dos fármacos , Idoso , Resultado do Tratamento , Hipoglicemiantes/uso terapêutico , Hipoglicemiantes/administração & dosagem , Tomografia Computadorizada por Raios X
5.
Anticancer Res ; 44(1): 361-368, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38159993

RESUMO

BACKGROUND/AIM: Atezolizumab plus bevacizumab (Atez/Bev) therapy is extremely effective and has a high response rate in hepatocellular carcinoma (HCC) treatment. This study investigated the efficacy of adding locoregional therapy with Atez/Bev for non-complete response (CR) HCC cases. PATIENTS AND METHODS: Twenty-eight HCC patients without CR during Atez/Bev therapy received locoregional therapy, and treatment efficacy was evaluated based on the modified RECIST criteria. RESULTS: The study included 23 male and five female participants with a mean age of 73.5 years. In the Atez/Bev and locoregional combination therapy effective group, both transcatheter arterial chemoembolization (TACE) and radiofrequency ablation (RFA) were combined in all patients. A significant reduction in neutrophil-to-lymphocyte ratio (NLR) was observed after adding locoregional therapy (p=0.039). Moreover, a combination of TACE and RFA was performed in all patients of the CR group. When assessing the add-on effect of the combination of TACE and RFA in the progressive disease (PD) group, seven patients were found to achieve non-PD. For patients who did not achieve PD, a significant NLR reduction was noted after the addition of locoregional therapy. CONCLUSION: Adding locoregional therapy such as TACE/RFA was found to exert an effect even in non-CR patients who had received Atez/Bev therapy. A reduction in NLR after locoregional therapy was noted. Even when a response is not obtained during Atez/Bev therapy, it is important to avail the option to add locoregional therapy, as it may contribute to improved prognosis via immune modulation with tolerable adverse reactions.


Assuntos
Carcinoma Hepatocelular , Ablação por Cateter , Quimioembolização Terapêutica , Neoplasias Hepáticas , Humanos , Masculino , Feminino , Idoso , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Bevacizumab/uso terapêutico , Ablação por Cateter/efeitos adversos , Quimioembolização Terapêutica/efeitos adversos , Resultado do Tratamento , Resposta Patológica Completa , Estudos Retrospectivos
6.
Medicine (Baltimore) ; 102(37): e35092, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37713820

RESUMO

This study aimed to investigate the risk factors for difficult endoscopic hemostasis in patients with colonic diverticular bleeding and to evaluate the efficacy and safety of transcatheter arterial embolization (TAE) for colonic diverticular bleeding. This study included 208 patients with colorectal diverticular hemorrhage. The non-interventional radiotherapy group consisted of patients who underwent successful spontaneous hemostasis (n = 131) or endoscopic hemostasis (n = 56), whereas the interventional radiotherapy group consisted of patients who underwent TAE (n = 21). Patient clinical characteristics were compared to identify independent risk factors for the interventional radiotherapy group. Furthermore, the hemostasis success rate, rebleeding rate, complications, and recurrence-free survival were compared between patients who underwent endoscopic hemostasis and those who underwent TAE. Bleeding from the right colon (odds ratio [OR]: 7.86; 95% confidence interval [CI]: 1.6-38.8; P = .0113) and systolic blood pressure <80 mm Hg (OR: 0.108; 95% CI: 0.0189-0.62; P = .0126) were identified as independent risk factors for the interventional radiology group. The hemostasis success rate (P = 1.00), early rebleeding rate (within 30 days) (P = .736), late rebleeding rate (P = 1.00), and recurrence-free survival rate (P = .717) were not significantly different between the patients who underwent TAE and those who underwent endoscopic hemostasis. Patients in the TAE group experienced more complications than those in the endoscopic hemostasis group (P < .001). Complications included mild intestinal ischemia (19.0%) and perforation requiring surgery (4.8%). Patients who required interventional radiotherapy were more likely to bleed from the right colon and presented with a systolic blood pressure of <80 mm Hg. TAE is an effective treatment for patients with colonic diverticular hemorrhage that is refractory to endoscopic hemostasis. However, complications must be monitored carefully.


Assuntos
Doenças Diverticulares , Divertículo do Colo , Embolização Terapêutica , Hemostase Endoscópica , Humanos , Embolização Terapêutica/efeitos adversos , Colo , Divertículo do Colo/complicações , Divertículo do Colo/terapia , Hemorragia Gastrointestinal/etiologia , Hemorragia Gastrointestinal/terapia
7.
Anticancer Res ; 43(8): 3647-3651, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37500124

RESUMO

BACKGROUND/AIM: The standard of care for patients with colorectal cancer and liver metastases, who fail to respond to systemic chemotherapy has not yet been established. Therefore, we investigated the prognostic value of transarterial chemoembolization (TACE) using irinotecan-loaded drug-eluting beads (DEBIRI) in treating liver metastases due to colorectal cancer. PATIENTS AND METHODS: Forty-six patients with colorectal cancer and unresectable liver metastases, who received systemic chemotherapy beyond the third line at our hospital between July 2014 and April 2020 were analyzed. They were divided into two groups: 1) Seventeen patients who received TACE with DEBIRI, and 2) twenty-nine patients who did not receive TACE. RESULTS: The median age was 68 years (range=37-85 years), and the male-to-female ratio was 29:17. The primary sites were the cecum in six cases, ascending colon in seven cases, transverse colon in two cases, descending colon in three cases, sigmoid colon in 14 cases, and rectum in 14 cases. All patients had received at least two prior systemic chemotherapy regimens including oxaliplatin-based and irinotecan-based regimens, and trifluridine tipiracil hydrochloride (38 patients) or regorafenib (12 patients) as the third line or beyond (overlap). Median survival was 272 days overall, 416 days in the TACE group, and 229 days in the non-TACE group, with significantly better survival in the TACE group (p=0.0126). CONCLUSION: TACE with DEBIRI may improve the prognosis of patients with liver metastases from unresectable colorectal cancer. We suggest that TACE with DEBIRI should be highly considered, especially in patients in whom liver metastasis may be a prognostic factor.


Assuntos
Antineoplásicos Fitogênicos , Carcinoma Hepatocelular , Quimioembolização Terapêutica , Neoplasias Colorretais , Neoplasias Hepáticas , Humanos , Masculino , Feminino , Idoso , Irinotecano/uso terapêutico , Camptotecina , Prognóstico , Antineoplásicos Fitogênicos/uso terapêutico , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/secundário , Carcinoma Hepatocelular/tratamento farmacológico , Resultado do Tratamento , Inibidores da Topoisomerase I/uso terapêutico , Neoplasias Colorretais/patologia
8.
Artigo em Inglês | MEDLINE | ID: mdl-37141075

RESUMO

This study evaluated how implant design features influence osseointegration. Two implant macrogeometries and surface treatments were evaluated: (1) progressive buttress threads with an SLActive surface (SLActive/BL), and (2) inner and outer trapezoidal threads with a nanohydroxyapatite coating over a dual acid-etched surface (Nano/U). Implants were placed in the right ilium of 12 sheep, and histologic and -metric analyses were conducted after 12 weeks. Percentages of bone-to-implant contact (BIC) and bone area fraction occupancy (BAFO) within the threads were quantified. Histologically, the SLActive/BL group showed greater and more intimate BIC than the Nano/U group. In contrast, Nano/U group depicted woven bone formation within the healing chambers, between the osteotomy wall and implant threads, and bone remodeling was evident at the outer thread tip. Significantly higher BAFO was seen in the Nano/U group than the SLActive/BL group at 12 weeks (P < .042). Different implant design features influenced the osseointegration pathway, supporting further investigations to describe the differences and clinical performance.


Assuntos
Implantes Dentários , Ovinos , Animais , Osseointegração , Implantação Dentária Endóssea , Osteogênese , Remodelação Óssea , Propriedades de Superfície , Titânio
9.
Clin J Gastroenterol ; 16(2): 254-262, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36449216

RESUMO

Acute pancreatitis is an uncommon occurrence in acute liver failure. Furthermore, such cases are rarely complicated by parenchymal hemorrhages. Herein, we report the case of a 69-year-old male patient with multiple pancreatic parenchymal hemorrhages concomitant with acute liver failure. The patient underwent conservative treatment for acute liver failure caused by hepatitis B virus infection. Plain computed tomography on the 30th day revealed two high-density mass lesions in the pancreatic body and tail, which were suspected to be multiple pancreatic parenchymal hemorrhages. Despite restarting gabexate mesylate, the patient died of multiple organ failure on the 49th day. The clinical information of the present case and our literature review of 61 similar cases in 43 case reports identified via a systematic keyword search of the PubMed database, which described acute pancreatitis concomitant with acute hepatitis and acute liver failure, will aid physicians in the diagnosis and treatment of this rare condition.


Assuntos
Falência Hepática Aguda , Pancreatite , Masculino , Humanos , Idoso , Pancreatite/complicações , Pancreatite/diagnóstico por imagem , Doença Aguda , Pâncreas , Hemorragia , Falência Hepática Aguda/complicações
10.
J Biomed Mater Res B Appl Biomater ; 109(11): 1787-1795, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-33763981

RESUMO

Medical devices such as orthopedic and dental implants may get infected by bacteria, which results in treatment using antibiotics. Since antibiotic resistance is increasing in society there is a need of finding alternative strategies for infection control. One potential strategy is the use of antimicrobial peptides, AMPs. In this study, we investigated the antibiofilm effect of the AMP, RRP9W4N, using a local drug-delivery system based on mesoporous titania covered titanium implants. Biofilm formation was studied in vitro using a safranine biofilm assay and LIVE/DEAD staining. Moreover, we investigated what effect the AMP had on osseointegration of commercially available titanium implants in vivo, using a rabbit tibia model. The results showed a sustained release of AMP with equal or even better antibiofilm properties than the traditionally used antibiotic Cloxacillin. In addition, no negative effects on osseointegration in vivo was observed. These combined results demonstrate the potential of using mesoporous titania as an AMP delivery system and the potential use of the AMP RRP9W4N for infection control of osseointegrating implants.


Assuntos
Antibacterianos , Peptídeos Antimicrobianos , Biofilmes/efeitos dos fármacos , Materiais Revestidos Biocompatíveis/química , Implantes Experimentais , Osseointegração , Titânio/química , Animais , Antibacterianos/química , Antibacterianos/farmacocinética , Antibacterianos/farmacologia , Peptídeos Antimicrobianos/química , Peptídeos Antimicrobianos/farmacocinética , Peptídeos Antimicrobianos/farmacologia , Cloxacilina/química , Cloxacilina/farmacocinética , Cloxacilina/farmacologia , Porosidade , Coelhos
11.
J Mech Behav Biomed Mater ; 103: 103598, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32090927

RESUMO

PURPOSE: The aim of this multi-scale in silico study was to evaluate the influence of resorption cavities on the mechanical properties and load distribution in cortical bone after implant placement with two different drilling protocols. MATERIAL AND METHODS: Two different micro-scale bone structures were assessed: cortical bone models with cavities (test) and without cavities (control) were designed from µCT data. In a macro-scale model, representing a mandibular ridge, oblique load of 150 N was applied on the implant-abutment. Maximum principal stress/strain, and shear stress/strain were calculated in the macro- and micro-scale models. RESULTS: Test presented anisotropic material properties. In tests, significantly greater maximum values of Maximum principal stress/strain were calculated in micro-scale model. These values were located at the implant neck area in the macro-scale model and in the proximity of cavities in the micro-scale model respectively. Greater values of shear stress/strain were found in the test along the mandibular horizontal plane. CONCLUSIONS: Cortical bone with resorption cavities following undersized drilling showed an impaired load distribution compared with bone without cavities. Subsequently, stress/strain distribution suggests that this bone model is more prone to microdamage, thus delaying the healing process.


Assuntos
Osso Cortical , Implantes Dentários , Fenômenos Biomecânicos , Simulação por Computador , Osso Cortical/diagnóstico por imagem , Análise do Estresse Dentário , Análise de Elementos Finitos , Estresse Mecânico
12.
Periodontol 2000 ; 81(1): 139-151, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31407440

RESUMO

This paper is aimed to present a biomaterials perspective in implant therapy that fosters improved bone response and long-term biomechanical competence from surgical instrumentation to final prosthetic rehabilitation. Strategies to develop implant surface texturing will be presented and their role as an ad hoc treatment discussed in light of the interplay between surgical instrumentation and implant macrogeometric configuration. Evidence from human retrieved implants in service for several years and from in vivo studies will be used to show how the interplay between surgical instrumentation and implant macrogeometry design affect osseointegration healing pathways, and bone morphologic and long-term mechanical properties. Also, the planning of implant-supported prosthetic rehabilitations targeted at long-term performance will be appraised from a standpoint where personal preferences (eg, cementing or screwing a prosthesis) can very often fail to deliver the best patient care. Lastly, the acknowledgement that every rehabilitation will have its strength degraded over time once in function will be highlighted, since the potential occurrence of even minor failures is rarely presented to patients prior to treatment.


Assuntos
Implantes Dentários , Materiais Biocompatíveis , Implantação Dentária Endóssea , Planejamento de Prótese Dentária , Prótese Dentária Fixada por Implante , Humanos , Osseointegração
13.
J Mech Behav Biomed Mater ; 97: 288-295, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31146202

RESUMO

This study evaluated the effect of alumina-blasted/acid-etched (AB/AE) or microabrasive blasting (C3-Microblasted) surface treatment on the osseointegration of commercially-pure Ti (grade II) and Ti-6Al-4V alloy (grade V) implants compared to as-machined surfaces. Surface characterization was performed by scanning electron microscopy and optical interferometry (IFM) to determine roughness parameters (Sa and Sq, n = 3 per group). One-hundred forty-four implants were placed in the radii of 12 beagle dogs, for histological (n = 72, bone-to-implant contact - BIC and bone-area-fraction occupancy -BAFO) and torque to interface failure test at 3 and 6 weeks (n = 72). SEM and IFM revealed a significant increase in surface texture for AB/AE and C3-Microblasted surfaces compared to machined surface, regardless of titanium substrate. Torque-to-interface failure test showed significant increase in values from as-machined to AB/AE and to C3-Microblasted. Considering time in vivo, alloy grade, and surface treatment, the C3-microblasted presented higher mean BIC values relative to AB/AE and machined surfaces for both alloy types. BAFO levels were significantly higher for both textured surfaces groups relative to the machined group at 3 weeks, but differences were not significant between the three surfaces for each alloy type at 6 weeks. Surface treatment resulted in roughness that improved osseointegration in Grade II and V titanium substrates.


Assuntos
Condicionamento Ácido do Dente/métodos , Óxido de Alumínio/química , Implantes Dentários , Osseointegração , Titânio/química , Ligas , Animais , Cães , Interferometria , Masculino , Microscopia Eletrônica de Varredura , Propriedades de Superfície , Resistência à Tração , Torque
14.
Int J Oral Maxillofac Implants ; 34(2): 320-328, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30883615

RESUMO

PURPOSE: To evaluate the effect of misfit at implant-level fixed partial dentures (ILFPDs) and marginal bone support on the generation of implant cracks. MATERIALS AND METHODS: This in vitro study included a mechanical fatigue test and finite element analysis. A mechanical cycling loading test was performed using 16 experimental models, each consisting of two parallel implants subdivided into four groups based on the misfit and the supporting bone condition. The framework, firmly seated at implants, was dynamically loaded vertically with a force of 1,600/160 N and 15 Hz for 1 × 106 cycles. Optical microscope, scanning electron microscope (SEM), and computed tomography three-dimensional (CT-3D) analyses were performed to detect impairments. Finite element models, representing the setups in the mechanical fatigue test, were used to represent the fatigue life. RESULTS: None of the mechanical components presented distortion or fracture at the macroscopic level during the test. In a microscopy evaluation, the fatigue test revealed scratches visible in the inner part of the conical portion of the implants regardless of the groups. SEM and CT-3D analysis revealed one implant from the misfit/no bone loss group with a microfracture in the inner part of the conical interface. The simulated effective stress levels in the coronal body were higher in the misfit groups compared with the no misfit groups. The misfit groups presented effective stress levels, above 375 MPa, that penetrated the entire wall thickness. The no bone loss group presented an effective stress level above 375 MPa along its axial direction. In the no misfit group, the area presenting effective stress levels above 375 MPa in the conical connection was larger for the bone loss group compared with the no bone loss group. CONCLUSION: This study confirmed that implant fracture is an unlikely adverse event. A clear pattern of effective distribution greater than fatigue limit stresses could be noticed when the misfit was present. The dynamic load simulation demonstrated that the crack is more likely to occur when implants are fully supported by marginal bone compared with a bone loss scenario. Within the limitations of this study, it is speculated that marginal bone loss might follow the appearance of an undetected crack. Further research is needed to develop safe clinical protocols with regard to ILFPD.


Assuntos
Perda do Osso Alveolar/fisiopatologia , Implantes Dentários/efeitos adversos , Prótese Dentária Fixada por Implante/efeitos adversos , Prótese Parcial Fixa , Estresse Mecânico , Fenômenos Biomecânicos , Análise do Estresse Dentário , Análise de Elementos Finitos , Humanos , Falha de Prótese/etiologia , Ajuste de Prótese
15.
Artigo em Inglês | MEDLINE | ID: mdl-30794262

RESUMO

This study investigated the level of magnetic energy around implants possessing a static magnetic field (SMF) and assessed the in vivo influence of SMF on bone regeneration. Implants possessing a sintered neodymium magnet internally were placed in a rabbit femur. An implant without SMF was placed as control. After 12 weeks of healing in vivo, the bone samples were subjected to histologic/histomorphometric evaluation. The bone-to-implant contact for the test group and the control group were 32.4 ± 13.6% and 17.1 ± 4.5%, respectively, and the differences were statistically significant (P < .05). The results suggested that the SMF promoted new bone apposition.


Assuntos
Fêmur/crescimento & desenvolvimento , Campos Magnéticos , Osteogênese/efeitos da radiação , Animais , Implantação Dentária Endóssea/métodos , Fêmur/efeitos da radiação , Fêmur/cirurgia , Coelhos
16.
Odontology ; 107(3): 353-359, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30617638

RESUMO

The aim of this study was to evaluate the accuracy in volumetric measurements obtained on an experimental model using an intraoral scanner and a gravimetric method. Three identical partial dentate maxillary acrylic models with three fabricated alveolar defects, in anterior and posterior regions, were scanned using an intraoral scanner (20 scans/defects). The defects differed in terms of size and distance of neighbouring teeth. As references, replicas of each defect were created using a dimensional stable silicone impression material. After measuring the mass of each replica, the volume was calculated by dividing the mass of each replica by the density of the impression material. The defects had a volume, according to the gravimetric method, ranging from 40.5 to 143.7 mm3. The scans were imported to metrology software for analyses. Accuracy was determined in terms of trueness and precision. The mean trueness for all defect types was 0.168 mm3 (SD 0.691, range 2.82). There was no statistical significant difference between the mean trueness for all defects measured (p = 0.910). The mean precision for all defect types was 0.147 mm3 (SD 0.524, range 2.86). There were no statistical significant differences between the dental models in regard to mean precision (p = 0.401), however, there were statistical significant differences between defects in position 1 and 2 (p = 0.002) and 1 and 3 (p = 0.001). Based on the findings of this study, the intraoral scanner utilized in the current study presented an acceptable level of accuracy when measuring volume of defects.


Assuntos
Desenho Assistido por Computador , Técnica de Moldagem Odontológica , Materiais para Moldagem Odontológica , Imageamento Tridimensional , Modelos Dentários
17.
Int J Periodontics Restorative Dent ; 39(6): 863­874, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-28834532

RESUMO

This retrospective study sought to compare a new implant (Astra Tech OsseoSpeed EV) with its predecessor (Astra Tech OsseoSpeed TX) by scanning electron microscopy and interferometry. Radiographic data from 19 patients who underwent implant restoration with EV (n = 49) with a median follow-up of 16 months were evaluated for mean bone level (MBL) changes from delivery of the definitive prosthesis. EV and TX did not differ in surface roughness, and both systems had a tight seal at the implant-abutment interface. The median MBL change of the EV was -0.02 mm mesiodistally after a median follow-up period of 16 months. Greater maintenance of MBL was found in the screw-retained restorations (n = 17) compared to cemented (0.35 ± 0.33 mm and -0.38 ± 0.76 mm, respectively; P = .03). The data suggest that EV shows minimal levels of bone loss and high implant survival.

18.
J Biomed Mater Res B Appl Biomater ; 107(3): 615-623, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30080320

RESUMO

This study investigated the effects of osseodensification drilling on the stability and osseointegration of machine-cut and acid-etched endosteal implants in low-density bone. Twelve sheep received six implants inserted into the ilium, bilaterally (n = 36 acid-etched, and n = 36 as-machined). Individual animals received three implants of each surface, placed via different surgical techniques: (1) subtractive regular-drilling (R): 2.0 mm pilot, 3.2 and 3.8 mm twist drills); (2) osseodensification clockwise-drilling (CW): Densah Bur (Versah, Jackson, MI) 2.0 mm pilot, 2.8, and 3.8 mm multifluted tapered burs; and (3) osseodensification counterclockwise-drilling (CCW) Densah Bur 2.0 mm pilot, 2.8 mm, and 3.8 mm multifluted tapered burs. Insertion torque was higher in the CCW and CW-drilling compared to the R-drilling (p < 0.001). Bone-to-implant contact (BIC) was significantly higher for CW (p = 0.024) and CCW-drilling (p = 0.006) compared to the R-drilling technique. For CCW-osseodensification-drilling, no statistical difference between the acid-etched and machine-cut implants at both time points was observed for BIC and BAFO (bone-area-fraction-occupancy). Resorbed bone and bone forming precursors, preosteoblasts, were observed at 3-weeks. At 12-weeks, new bone formation was observed in all groups extending to the trabecular region. In low-density bone, endosteal implants inserted via osseodensification-drilling presented higher stability and no osseointegration impairments compared to subtractive regular-drilling technique, regardless of evaluation time or implant surface. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 107B: 615-623, 2019.


Assuntos
Interface Osso-Implante , Osso Esponjoso/metabolismo , Implantes Experimentais , Osseointegração , Osteoblastos/metabolismo , Animais , Osso Esponjoso/patologia , Masculino , Osteoblastos/patologia , Ovinos
19.
J Biomed Mater Res B Appl Biomater ; 107(5): 1320-1328, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30199603

RESUMO

The study evaluated the effects of a Supercritical CO2 (scCO2 ) on a commercially available decellularized/delipidized naturally derived porcine pericardium collagen membrane, Vitala®. The Vitala® and scCO2 treated experimental membranes were evaluated for guided tissue regeneration (GTR) of periodontal tissue in class III furcation defects utilizing a dog model. Physical material characterization was performed by scanning electron microscopy (SEM), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC). The in vivo portion of the study was allocated to three-time points (6, 12, and 24-weeks) using standardized class III furcation defects created in the upper second and third premolars. The experimental defects (n = 5) were covered with either a collagen membrane (positive control), scCO2 -treated collagen membrane (experimental) or no membrane (negative control). Following sacrifice, histologic serial sections were performed from cervical to apical for morphologic/morphometric evaluation. Morphometric evaluation was carried out by ranking the presence of collagen membrane, amount of bone formation within the defect site and inflammatory cell infiltrate content. SEM showed the experimental scCO2 -treated membrane to have a similar gross fibrous appearance and chemical structure in comparison to the Vitala® Collagen membrane. A significant increase in membrane thickness was noted in the scCO2 -treated membranes (366 ± 54 µm) vs non-treated membranes (265 ± 75 µm). TGA and DSC spectra indicated no significant qualitative differences between the two membranes. For the in vivo results, both membranes indicated significantly greater amounts of newly formed bone (scCO2 : 2.85 ± 1.1; Vitala®: 2.80 ± 1.0) within the covered defects relative to uncovered controls (0.8 ± 0.27) at 24 weeks. Both membrane types gradually degraded as time elapsed in vivo from 6 to 12 weeks, and presented nearly complete resorption at 24 weeks. The inflammatory infiltrate at regions in proximity with the membranes was commensurate with healthy tissue levels from 6 weeks in vivo on, and periodontal ligament regeneration onset was detected at 12 weeks in vivo. The effect of the supplementary scCO2 treatment step on the collagen membrane was demonstrated to be biocompatible, allowing for the infiltration of cells and degradation over time. The treated membranes presented similar performance in GTR to non-treated samples in Class III furcation lesions. Defects treated without membranes failed to achieve regeneration of the native periodontium. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 107B: 1320-1328, 2019.


Assuntos
Dióxido de Carbono/química , Colágeno , Membranas Artificiais , Pericárdio/química , Ligamento Periodontal , Regeneração , Animais , Colágeno/química , Colágeno/farmacologia , Cães , Ligamento Periodontal/lesões , Ligamento Periodontal/patologia , Ligamento Periodontal/fisiologia , Suínos
20.
J Long Term Eff Med Implants ; 29(4): 295-302, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-32749134

RESUMO

This study evaluates the influence of two surface physicochemical modifications on osseointegration parameters of a healing chamber implant design. We examine dental implants with internal and external trapezoidal threads that have the following surface modifications: dual acid etching (DAE) and nano-hydroxyapatite (HA) coating over DAE surface (Nano). We installed implants in the right ilium of sheep and conducted histologic/metric analyses after 3 and 12 wk in vivo. We quantified the percentage of bone-to-implant contact (%BIC) and bone area fraction occupancy (%BAFO) within implant threads. Histologic micrographs indicate early bone formation within the healing chambers of implants with Nano surface relative to DAE surface. Histomorphometric analysis demonstrates there to be no significant differences in %BIC between 3 and 12 wk (p = 0.298). Compared to DAE, Nano shows more bone formation in contact with implant, regardless of time (p < 0.025). We observe > %BAFO at 12 wk relative to 3 wk, which differs significantly for Nano (p < 0.038). Implant surface treatment affects the amounts of bone formation within healing chambers, with Nano significantly outperforming DAE at 12 wk (p < 0.025). Nano presents a synergistic effect with implant design, improving osseointegration parameters.

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