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2.
J Dent ; 139: 104748, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37863173

RESUMEN

OBJECTIVES: This meta-analysis aimed to determine the accuracy of currently available computer-assisted implant surgery (CAIS) modalities under in vitro conditions and investigate whether these novel techniques can achieve clinically acceptable accuracy. DATA: In vitro studies comparing the postoperative implant position with the preoperative plan were included. Risk of bias was assessed using the Quality Assessment Tool For In Vitro Studies (QUIN Tool) and a sensitivity analysis was conducted using funnel plots. SOURCES: A systematic search was performed on April 18, 2023, using the following three databases: MEDLINE (via PubMed), EMBASE, and Cochrane Central Register of Controlled Trials. No filters or restrictions were applied during the search. RESULTS: A total of 5,894 studies were included following study selection. Robotic- and static CAIS (sCAIS) had the most accurate and clinically acceptable outcomes. sCAIS was further divided according to the guidance level. Among the sCAIS groups, fully guided implant placement had the greatest accuracy. Augmented reality-based CAIS (AR-based CAIS) had clinically acceptable results for all the outcomes except for apical global deviation. Dynamic CAIS (dCAIS) demonstrated clinically safe results, except for horizontal apical deviation. Freehand implant placement was associated with the greatest number of errors. CONCLUSIONS: Fully guided sCAIS demonstrated the most predictable outcomes, whereas freehand sCAIS demonstrated the lowest accuracy. AR-based and robotic CAIS may be promising alternatives. CLINICAL SIGNIFICANCE: To our knowledge, this is the first meta-analysis to evaluate the accuracy of robotic CAIS and investigate the accuracy of various CAIS modalities.


Asunto(s)
Implantes Dentales , Cirugía Asistida por Computador , Implantación Dental Endoósea/métodos , Cirugía Asistida por Computador/métodos , Diseño Asistido por Computadora , Tomografía Computarizada de Haz Cónico , Imagenología Tridimensional
3.
BMC Oral Health ; 23(1): 575, 2023 08 18.
Artículo en Inglés | MEDLINE | ID: mdl-37596610

RESUMEN

BACKGROUND: The purpose of this in vitro study was to compare the accuracy of implant placement in model surgeries according to the design of the drills (straight drills or step drills) used to finalize the implant bed during pilot-guided static computer-assisted implant surgery (sCAIS). METHODS: Model surgeries were carried out on resin models randomly assigned to three study groups. Virtual planning software (coDiagnostiX 10.6, Dental Wings, Montreal, Canada) was used to plan the implant positions. In Groups 1 and 2, pilot-guided sCAIS was performed. Straight drills were used in Group 1, and step drills were used in Group 2 to finalize the implant beds. In Group 3, fully guided sCAIS was performed using a universal fully guided kit (RealGUIDE Full Surgical Kit 3DIEMME, RealGUIDE, Cantù, Como, Italy). A total of 90 dental implants (Callus Pro, Callus Implant Solutions GmbH, Nuremberg, Germany) were placed (six implants per model, five models per study group). The primary outcome variables (angular deviation, coronal global deviation, and apical global deviation) were calculated for all implants based on the comparison of the preoperative surgical plan with the postoperative scans. RESULTS: Group 2 (coronal global deviation, 0.78 ± 0.29 mm; apical global deviation, 1.02 ± 0.56 mm) showed significantly lower values of both global deviation variables than Group 1 (coronal global deviation, 0.95 ± 0.20 mm; apical global deviation, 1.42 ± 0.49 mm). However, there was no significant difference in angular deviation between Groups 1 and 2 (7.56 ± 2.92° and 6.44 ± 2.84°). Group 3 produced significantly lower values of all three primary outcome variables (angular deviation, 2.36 ± 0.90°; coronal global deviation, 0.59 ± 0.28 mm; apical global deviation, 0.90 ± 0.29 mm) than Group 1 and significantly lower angular deviation and coronal global deviation values than Group 2. CONCLUSIONS: The design of the drills used to finalize implant osteotomies during pilot-guided sCAIS influences dental implant placement accuracy. Using step drills instead of straight drills for final osteotomies decreases deviation from the surgical plan. The fully guided approach performed better than the pilot-guided sCAIS.


Asunto(s)
Implantación Dental , Implantes Dentales , Cirugía Asistida por Computador , Humanos , Implantación Dental/instrumentación , Proyectos de Investigación
4.
J Dent ; 119: 104070, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35183695

RESUMEN

OBJECTIVES: This in vitro study aimed to compare the accuracy of implant placement in model surgeries carried out by implementation of three different methods. METHODS: An in vitro study was conducted on 3D printed study models randomly assigned to three study groups. In Group 1, model surgeries were assisted by augmented reality (AR)based dynamic navigation (Innooral System, Innoimplant Ltd, Budapest, Hungary). In Group 2, implants were placed with a free-hand method, and in Group 3, static Computer Assisted Implant Surgery (CAIS) was used (coDiagnostiX software, version 10.4 Dental Wings, Montreal, CA, USA). A total of 48 dental implants (Callus Pro, Callus Implant Solutions GmbH, Hamburg, Germany) were placed (16 implants in four models per study group). The primary outcome variables were angular deviation, coronal, and apical global deviation. These were calculated for all implants based on preoperative registration of the surgical plan and postoperative cone beam computed tomography (CBCT) reconstruction. RESULTS: The accuracy of implant placement using AR-based dynamic navigation showed no significant difference compared to static CAIS (angular deviation, 4.09 ± 2.79° and 3.21 ± 1.52°; coronal deviation, 1.27 ± 0.40 mm and 1.31 ± 0.42 mm; and apical global deviation 1.34 ± 0.41 mm and 1.38 ± 0.41 mm). Global deviation results were significantly lower with AR-based dynamic navigation than with the free-hand approach (coronal and apical global deviation of 1.93 ± 0.79 mm and 2.28 ± 0.74 mm, respectively). CONCLUSIONS: Implant positioning accuracy of AR-based dynamic navigation was comparable to that of static CAIS and superior to that obtained by the free-hand approach. CLINICAL SIGNIFICANCE: Implementing Augmented Reality based dynamic Computer Assisted Implant Surgery (CAIS) in model surgeries may allow to obtain an implant positioning accuracy comparable to that provided by static CAIS, and superior to that obtained through the free-hand approach. Further clinical studies are necessary to determine the feasibility of AR-based dynamic navigation.


Asunto(s)
Realidad Aumentada , Implantes Dentales , Diseño Asistido por Computadora , Computadores , Tomografía Computarizada de Haz Cónico , Implantación Dental Endoósea , Humanos , Imagenología Tridimensional
8.
J Lipid Res ; 60(8): 1365-1378, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31164391

RESUMEN

Triglycerides (TGs) are the main energy storage form that accommodates changing organismal energy demands. In Drosophila melanogaster, the TG lipase Brummer is centrally important for body fat mobilization. Its gene brummer (bmm) encodes the ortholog of mammalian adipose TG lipase, which becomes activated by α/ß-hydrolase domain-containing 5 (ABHD5/CGI-58), one member of the paralogous gene pair, α/ß-hydrolase domain-containing 4 (ABHD4) and ABHD5 In Drosophila, the pummelig (puml) gene encodes the single sequence-related protein to mammalian ABHD4/ABHD5 with unknown function. We generated puml deletion mutant flies, that were short-lived as a result of lipid metabolism changes, stored excess body fat at the expense of glycogen, and exhibited ectopic fat storage with altered TG FA profile in the fly kidneys, called Malpighian tubules. TG accumulation in puml mutants was not associated with increased food intake but with elevated lipogenesis; starvation-induced lipid mobilization remained functional. Despite its structural similarity to mammalian ABHD5, Puml did not stimulate TG lipase activity of Bmm in vitro. Rather, Puml acted as a phospholipase that localized on lipid droplets, mitochondria, and peroxisomes. Together, these results show that the ABHD4/5 family member Puml is a versatile phospholipase that regulates Drosophila body fat storage and energy metabolism.


Asunto(s)
Proteínas de Drosophila/metabolismo , Metabolismo Energético , Lipasa/metabolismo , Lipogénesis , Lisofosfolipasa/metabolismo , Túbulos de Malpighi/enzimología , Animales , Proteínas de Drosophila/genética , Drosophila melanogaster , Eliminación de Gen , Lipasa/genética , Lisofosfolipasa/genética
10.
Int Orthod ; 16(3): 470-485, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-30006082

RESUMEN

The aim of the present study was to comprehensively assess the posttreatment effect of premolar extraction versus non-extraction on the position and development of the lower third molars. The sample consisted of 227 patient's pre- and posttreatment panoramic radiographs (53 with four premolar extractions, 174 without extractions). The position and developmental stage of the lower third molars were evaluated by using Pell-Gregory's, Winter's, modified Miloro-DaBell's and Demirjian's classifications, respectively. Premolar extraction had a considerably positive influence on the position and development of the lower third molars and therefore could provide better prognosis for their eruption.


Asunto(s)
Diente Premolar/cirugía , Tercer Molar , Extracción Dental , Adolescente , Niño , Femenino , Humanos , Masculino , Tercer Molar/crecimiento & desarrollo , Radiografía Panorámica
13.
PLoS One ; 7(9): e45440, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23024821

RESUMEN

The apicomplexan parasite Toxoplasma gondii is regularly transmitted to humans via the ingestion of contaminated meat products from chronically infected livestock. This route of transmission requires intracellular development and long-term survival of the parasite within muscle tissue. In this study, we determined the cell-autonomous immunity of mature primary embryonic or C2C12 skeletal muscle cells (SkMCs) to infection with T. gondii. Non-activated SkMCs and control fibroblasts sustained parasite replication; however, interferon (IFN)-γ significantly inhibited parasite growth in SkMCs but not in fibroblasts. Intracellular parasite replication was diminished by IFN-γ whereas host cell invasion was not affected. Tumor necrosis factor (TNF) did not further increase the IFN-γ-triggered host defense of SkMCs against Toxoplasma. Remarkably, IFN-γ alone or in combination with TNF decreased the high level of T. gondii bradyzoite formation being observed in non-activated SkMCs. Stimulation of SkMCs with IFN-γ strongly triggered expression of inducible nitric oxide synthase (iNOS) transcripts, and induced significantly higher levels of nitric oxide (NO) in SkMCs than in fibroblasts. Consequently, pharmacological inhibition of iNOS partially abrogated the IFN-γ-induced toxoplasmacidal activity of SkMCs. In addition, SkMCs strongly up-regulated immunity-regulated GTPases (IRGs) following stimulation with IFN-γ. IRGs accumulated on Toxoplasma-containing vacuoles in SkMCs in a parasite strain-dependent manner. Subsequent vacuole disruption and signs of degenerating parasites were regularly recognized in IFN-γ-treated SkMCs infected with type II parasites. Together, murine SkMCs exert potent toxoplasmacidal activity after stimulation with IFN-γ and have to be considered active participants in the local immune response against Toxoplasma in skeletal muscle.


Asunto(s)
GTP Fosfohidrolasas/metabolismo , Interferón gamma/farmacología , Músculo Esquelético/metabolismo , Músculo Esquelético/parasitología , Óxido Nítrico/biosíntesis , Toxoplasma/efectos de los fármacos , Toxoplasma/crecimiento & desarrollo , Animales , Diferenciación Celular , Línea Celular , Ratones , Músculo Esquelético/citología , Mioblastos/citología , Óxido Nítrico Sintasa de Tipo II/metabolismo , Toxoplasma/inmunología , Factores de Necrosis Tumoral/farmacología
14.
Int J Med Microbiol ; 299(5): 381-8, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19097936

RESUMEN

Toxoplasma gondii is one of the most common eukaryotic parasites and an important opportunistic pathogen of humans. The interconversion from proliferative tachyzoites into quiescent encysted bradyzoites plays pivotal roles in the lifelong persistence of T. gondii in its host and the pathogenesis of toxoplasmosis. Stage conversion and persistence in skeletal muscle tissue may be particularly important for the food-borne transmission of T. gondii to humans via raw or undercooked meat products. Here, we have followed the transition of tachyzoites to bradyzoites after infection of skeletal muscle cells (SkMC). Primary murine myoblasts were differentiated to multinucleated syncytial myotubes that displayed regular contractions in vitro and expressed myogenic markers Myf5 and MyoD. Tachyzoites of T. gondii invaded SkMC within 4h of infection and started to replicate within 24h of infection. Remarkably, intracellular tachyzoites readily differentiated to bradyzoites in SkMC without the need of exogenous stress factors. Double immunofluorescence labelling revealed significantly higher percentages of bradyzoite-containing vacuoles in SkMC than in murine fibroblasts at 24h until 6 days after infection. Furthermore, transcript levels of bradyzoite-specific ENO1 but not tachyzoite-specific ENO2 strongly increased in T. gondii-infected SkMC until 6 days of infection. These findings indicate that the commitment of T. gondii to differentiate to bradyzoites in SkMC does not require exogenous stress factors but could be rather regulated by cell-type specific factors.


Asunto(s)
Fibroblastos/parasitología , Células Musculares/parasitología , Músculo Esquelético/parasitología , Toxoplasma/crecimiento & desarrollo , Animales , Células Cultivadas , Ratones , Fibras Musculares Esqueléticas/parasitología
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