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1.
J Oral Rehabil ; 51(8): 1521-1529, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38717007

RESUMEN

BACKGROUND: Current clinical approaches to regenerate temporomandibular joint (TMJ) articulating cartilage defects only treat the symptoms (i.e. pain and dysfunction) and do not seek to restore joint integrity for long-term relief. Therefore, we investigated a novel self-assembling tissue-engineered cartilage to overcome this significant clinical issue for TMJ regenerative purposes. OBJECTIVES: Examine the maturation of dynamic self-regenerating cartilage (dSRC) using auricular chondrocytes and evaluate a novel combinatorial approach with fractional laser treatment and dSRC implantation for TMJ cartilage repair. MATERIALS AND METHODS: A suspension of 107 freshly harvested rabbit ear chondrocytes was cultured under a continuous reciprocating motion to form the dSRC. After 2, 4 and 8 weeks of culture, dSRC samples were stained with H&E, Safranin-O and Toluidine Blue. Immunohistochemistry (IHC) was performed for collagens type I and II. Channels (300-500 µm diameter and 1.2-1.5 mm depth) were created in six freshly harvested condyles using a fractional Erbium laser. Two groups were tested: dSRC in a laser-ablated lesion (experimental) and an empty laser-ablated channel (control). TMJ condyles were cultured for up to 8 weeks and analysed as described above. RESULTS: H&E staining showed a high cell density in dSRC compared to native cartilage. All dSRC groups demonstrated intense Safranin-O staining, indicating high glycosaminoglycan (GAG) production and intense Toluidine Blue staining showed high proteoglycan content. IHC confirmed that dSRC consisted predominantly of collagen type II. The experimental group showed improved cartilage repair at both time points compared to the empty channels. CONCLUSION: dSRC viability and successful matrix formation were demonstrated in vitro. The combination of fractional laser ablation and dSRC implantation enhanced cartilage repair.


Asunto(s)
Cartílago Articular , Condrocitos , Regeneración , Articulación Temporomandibular , Ingeniería de Tejidos , Animales , Conejos , Condrocitos/trasplante , Ingeniería de Tejidos/métodos , Articulación Temporomandibular/cirugía , Articulación Temporomandibular/patología , Regeneración/fisiología , Cartílago Articular/cirugía , Cartílago Articular/patología , Trastornos de la Articulación Temporomandibular/cirugía , Trastornos de la Articulación Temporomandibular/fisiopatología , Trastornos de la Articulación Temporomandibular/terapia , Células Cultivadas , Cartílago Auricular/fisiología , Técnicas In Vitro
2.
J Oral Rehabil ; 51(2): 394-403, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37830126

RESUMEN

BACKGROUND: In the last decade, tissue-engineering strategies for regenerating the temporomandibular joint (TMJ) have been investigated. This may be a promising strategy for the minimally invasive restoration of joint integrity. OBJECTIVES: To evaluate whether dental pulp stem cells (DPSCs) loaded in a light-occured hydrogel made of gelatin methacryloyl (GelMA) enhance the regeneration of osteochondral defects in the rabbit TMJ. MATERIALS AND METHODS: Defects were filled with GelMA alone (control group; n = 4) or filled with GelMA loaded with rabbit DPSCs (experimental group; n = 4), In one group, the TMJ capsule was opened without creating a defect (sham group; n = 2). The following micro-CT parameters were analysed: bone volume to total volume ratio (BV/TV%) and bone mineral density (BMD). Histological evaluation was performed to assess cartilage regeneration features. A semi-quantitative scoring system was also used to evaluate the defects. RESULTS: All groups had no statistical difference regarding the micro-CT parameters. The highest mean healing score was found for the experimental group. After 4 weeks, there were no signs of hydrogel in either group or no signs of inflammation in the adjacent tissues. The tissue formed in the defect was dense fibrous connective tissue. CONCLUSION: Adding DPSCs to GelMA did not provide a regenerative enhancement in TMJ osteochondral defects. This resulted in similar micro-CT parameters after 4 weeks of healing, with improved signs of subchondral bone regeneration but no cartilage regeneration.


Asunto(s)
Pulpa Dental , Hidrogeles , Animales , Conejos , Articulación Temporomandibular , Ingeniería de Tejidos/métodos , Células Madre
3.
J Biomech Eng ; 145(9)2023 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-37195691

RESUMEN

Short dental implants with platform matching connection have been used for the rehabilitation of atrophic jaws whenever standard-length dental implants cannot be placed without prior bone augmentation. Yet, there remains a lack of data regarding the risk of technical failures when the all-on-4 configuration is performed in atrophic jaws with platform-switching distal short dental implants. Thus, the current study used the finite element method to evaluate the mechanical behavior at the level of the prosthetic components of the all-on-4 concept performed in atrophic mandible using short-length distal implants with platform switching (PSW) connection. Three models of the all-on-4 configuration were generated in human atrophic mandibles. The geometric models consisted of PSW connection tilted standard (AO4T; θ = 30 deg; 11 mm-length), straight standard (AO4S; θ = 0 deg; 11 mm-length) and straight short (AO4Sh; θ = 0 deg; 8 mm-length) distal implants. A resultant force of 300 N was performed obliquely in the left side and posterior region of the prosthetic bar. The von Mises equivalent stress (σvm) and maximum and minimum principal stresses (σmax and σmin) were performed at level of the prosthetic components/implants and peri-implant bone crest, respectively. The general displacement of the models was also evaluated. The stress analysis was performed on the side of load application. The AO4S configuration showed the lowest values of σvm in the mesial left (ML) and distal left (DL) abutments (37.53 MPa and 232.77 MPa, respectively) and dental implants (91.53 MPa and 231.21 MPa, respectively). The AO4Sh configuration showed the highest values of σvm in the bar screw (102.36 MPa), abutment (117.56 MPa), and dental implant (293.73 MPa) of the ML area. Among the models, the highest values of σmax and σmin were noticed in the peri-implant bone crest of the AO4T design (131.48 MPa and 195.31 MPa, respectively). All models showed similar values of general displacements, which were concentrated in the mandible symphysis. The all-on-4 configurations designed with PSW connection and tilted standard (AO4T; θ = 30 deg; 11 mm-length), straight standard (AO4S; θ = 0 deg; 11 mm-length) or straight short (AO4Sh; θ = 0 deg; 8 mm-length) distal implants were not associated with higher odds of technical failures. The AO4Sh design may be a promising option for the prosthetic rehabilitation of atrophic jaws.


Asunto(s)
Implantes Dentales , Humanos , Estrés Mecánico , Análisis de Elementos Finitos , Mandíbula/cirugía , Análisis del Estrés Dental
4.
Acta Neurochir (Wien) ; 165(8): 2293-2298, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37284839

RESUMEN

PURPOSE: Photosealing of many biological tissues can be achieved using a biocompatible material in combination with a dye that is activated by visible light to chemically bond over the tissue defect via protein cross-linking reactions. The aim of this study was to test the efficacy of photosealing using a commercially available biomembrane (AmnioExcel Plus) to securely close dural defects in comparison to another sutureless method (fibrin glue) in terms of repair strength. METHODS: Two-millimeter diameter holes were created in dura harvested from New Zealand white rabbits and repaired ex vivo using one of two methods: (1) in n = 10 samples, photosealing was used to bond a 6-mm-diameter AmnioExcel Plus patch over the dural defect, and (2) in n = 10 samples, fibrin glue was used to attach the same patch over the dural defect. Repaired dura samples were then subjected to burst pressure testing. Histological analysis was also performed of photosealed dura. RESULTS: The mean burst pressures of rabbit dura repaired with photosealing and fibrin glue were 302 ± 149 mmHg and 26 ± 24 mmHg, respectively. The increased repair strength using photosealing was statistically significant and considerably higher than the normal intracranial pressure of ~ 20 mmHg. Histology demonstrated a tight union at the interface between the dura surface and patch with no disruption of the dura structure. CONCLUSION: The results of this study suggest that photosealing performs better than fibrin glue for the fixation of a patch for ex vivo repair of small dural defects. Photosealing is worthy of testing in pre-clinical models for the repair of dural defects.


Asunto(s)
Materiales Biocompatibles , Adhesivo de Tejido de Fibrina , Animales , Conejos , Materiales Biocompatibles/uso terapéutico , Duramadre/cirugía , Duramadre/patología
5.
Surg Innov ; 30(2): 143-149, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35603581

RESUMEN

Background. There have been few advances in technique since vascular anastomosis was performed with silk suture on a curved needle in 1902. This technique results in disruption of the endothelium with exposed intraluminal suture, both of which may lead to thrombocyte aggregation, intimal hyperplasia, and vascular stenosis. A variety of alternative techniques have been explored, with limited success. Photochemical tissue bonding (PTB) is a light-activated methodology of rapidly cross-linking tissue interfaces at the molecular level. Herein, we describe a new technique for anastomosis of venous interposition graft in an ovine model of femoral artery bypass utilizing PTB. Methods. Polypay specific pathogen free sheep (n = 5; 40-45 kg) underwent femoral artery bypass utilizing saphenous vein. The femoral artery was transected and reversed saphenous vein was implanted as an interposition graft. The proximal anastomosis was created as a vein-over-artery cuff utilizing PTB, and the distal anastomosis was created with standard interrupted 8-0 polypropylene suture. Four weeks post-index operation, femoral angiogram was performed to evaluate patency, tortuosity, and luminal diameter. All bypass grafts were harvested and longitudinal and transverse histological sections from the proximal anastomosis were analyzed. Results. The PTB anastomoses (n = 5) were immediately watertight and patent. All animals survived the 28-day study duration. Angiography revealed patent grafts with no aneurysm or stenosis (n = 5). Histologic examination revealed integration of the venous endothelium with the arterial adventitia. Conclusion. Photochemical tissue bonding creates an immediate strong, watertight vascular anastomosis that can withstand physiologic arterial pressure and remains patent at 28 days without the need for intraluminal suture.


Asunto(s)
Procedimientos Quirúrgicos Vasculares , Animales , Ovinos , Grado de Desobstrucción Vascular , Constricción Patológica , Anastomosis Quirúrgica/métodos
6.
J Oral Maxillofac Surg ; 80(2): 303-312, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34822754

RESUMEN

PURPOSE: The purpose of this study was to develop and characterize beta-tricalcium phosphate (ß-TCP)/polycaprolactone (PCL) scaffolds, with 2 different ratios (50/50% and 65/35%), using 3-dimensionally (3D) printed dissolvable molds, and to evaluate cellular growth and osteogenic differentiation of both groups seeded with porcine bone marrow stem cells (pBMSCs) under dynamic culture in vitro. MATERIALS AND METHODS: Two different groups of scaffolds were produced: group 1 (n = 40) with a ratio (wt%) of 50/50% and group 2 (n = 40) with 65/35% of ß-TCP/PCL. Physicochemical, morphological, and mechanical characterization of the scaffolds were performed. Scaffolds were seeded with pBMSCs and differentiated osteogenically in dynamic culture. Cell density, distribution, and viability were assessed. Osteogenic differentiation was examined through alkaline phosphatase (ALP) staining, immunofluorescence, and photospectrometry. RESULTS: Osteogenic differentiated constructs showed homogenous and viable cell distribution. Cell density was significantly higher (P < .05) for 65/35% scaffolds at 10 days postseeding, whereas at 6 weeks, cell number equalized for both groups. ALP activity increased over time and was significantly higher (P < .05) for 65/35% scaffolds at 14 days postseeding. CONCLUSIONS: The mechanical properties of the developed 65/35% scaffolds were within the range of natural trabecular bone. Moreover, the 65/35% scaffolds showed biological advantages, such as higher cell growth and higher ALP activity.


Asunto(s)
Osteogénesis , Andamios del Tejido , Animales , Huesos , Fosfatos de Calcio/farmacología , Diferenciación Celular , Proliferación Celular , Células Cultivadas , Humanos , Poliésteres/química , Porcinos , Andamios del Tejido/química
7.
Clin Oral Investig ; 26(2): 1477-1489, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34386857

RESUMEN

OBJECTIVE: To assess the interaction between chemotherapy and normal tissues is critical to assure quality of life during and after the treatment of cancer. This study evaluated the influence of cisplatin (CIS) and 5-fluorouracil (5-FU) over the peri-implant tissues around osseointegrated titanium implants in animals previously exposed to nicotine. Materials and methods One hundred twenty male rats were divided into two groups, receiving via subcutaneous injection, either physiological saline solution (PSS) (n = 30) or nicotine hemissulfate (NIC) (n = 90) for 30 days prior to implants' placement. One titanium implant (4.0 × 2.2 mm) was installed in each tibia of all animals. PSS and NIC were continued for 30 days after surgery. Five days after cessation, rats were subdivided into three subgroups in accordance with systemic treatments with either PSS, CIS, or 5-FU. Euthanasia was performed at 50, 65, and 95 days post-surgery. Histometric, histopathological, and immunohistochemical analyses were performed. RESULTS: NIC-CIS and NIC-5FU presented lower BIC (50, 65, and 95 days) and bone area fraction occupancy (BAFO) (65 and 95 days) than group NIC. Intense inflammatory infiltration, severe tissue breakdown, reduced expression of bone formation biomarkers, and upregulation of TRAP were observed in NIC-CIS and NIC-5FU when compared with group NIC. TRAP expression was significantly higher in NIC-5FU as compared with NIC-CIS at 50 and 95 days. Groups NIC, NIC-CIS, and NIC-5FU presented statistically significant negative impact in all outcome parameters than group PSS. CONCLUSION: CIS and 5-FU severely disrupted the peri-implant tissues around osseointegrated implants in animals previously exposed to nicotine. CLINICAL RELEVANCE: Assessing the interaction between chemotherapy and normal tissues is critical to assure quality of life during and after the cancer treatment.


Asunto(s)
Antineoplásicos , Implantes Dentales , Animales , Masculino , Nicotina , Oseointegración , Calidad de Vida , Ratas , Tibia , Titanio
8.
Am J Orthod Dentofacial Orthop ; 161(3): e215-e222, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34924285

RESUMEN

INTRODUCTION: Orthodontic tooth movement is reliant on the process of bone remodeling, and a variety of medications impact the ability of teeth to move through bone. Marijuana is the most widely used recreational drug in the world, and early studies suggest the drug impacts bone remodeling as tetrahydrocannabinol binds to cannabinoid receptors which play a role in bone homeostasis. This study aimed to assess the impact of dronabinol on alveolar bone remodeling in rats with otherwise healthy tissue when subjected to orthodontic forces. METHODS: Thirty male Sprague Dawley rats were equally allocated into 2 groups. Orthodontic appliances were placed in all animals, which consisted of a nickel-titanium coil ligated from the maxillary first molar to the central incisor. The appliance was activated to deliver a force to move teeth together. Over 21 days, daily injections of either dronabinol or the control (solvent) were given to the rats. Cephalometric analysis, histology, and bone remodeling profiles of both groups were analyzed and compared. RESULTS: Teeth moved in both the dronabinol and control groups (P <0.05). Tooth movement in the control group followed the typical process of orthodontic tooth movement: periodontal width narrowing and bone resorption on the compression side of the tooth, with an overall decrease in the height of the alveolar bone. In contrast, the dronabinol group showed an abnormal response to tooth movement: no bone resorption on the compression side of the tooth, increased bone formation on the tension side, and the maintenance of the height of the alveolar crest. In the dronabinol group, there were also significantly more osteoclasts and osteoblasts in the alveolar bone than in the control group. CONCLUSIONS: These results demonstrate that dronabinol attenuates orthodontic tooth movement by decreasing bone resorption, which could have implications for other bone-related recovery processes.


Asunto(s)
Dronabinol , Técnicas de Movimiento Dental , Proceso Alveolar/patología , Animales , Remodelación Ósea/fisiología , Dronabinol/farmacología , Masculino , Osteoclastos/patología , Ratas , Ratas Sprague-Dawley , Técnicas de Movimiento Dental/métodos
9.
J Contemp Dent Pract ; 23(6): 618-622, 2022 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-36259301

RESUMEN

AIM: The aim of this study was to evaluate the profile of patients undergoing dental treatment in relation to cannabis use. MATERIALS AND METHODS: A comprehensive questionnaire was used to address the type of cannabis preparations, route of intake, frequency of usage, and potential reasoning for use (recreational vs medical use) of patients from the MGH Dental Group. RESULTS: Seventy-six adult patients completed the survey. Sixty-one percent of the participants were female, with the majority (59%) of the participants being ≥51 years or older. Twelve of the 76 participants (16%) were 18-30 years old. The remaining 19 patients (25%) who participated in the study were 31-50 years old. The sample included participants who were predominately non-Hispanic (63 patients, 83%) and White (59 patients, 78%). The majority of patients either had their first use of cannabis prior to 18 years of age (36%) or did not respond to this question (34%) at all. The predominant age at consistent cannabis use was 18-30 years (13%). The most common method of cannabis intake in the preceding year for participants was smoking, followed by ingesting, using cannabidiol (CBD), and vaping (least common). Recreational cannabis use was reported in 47% of the participants vs 28% of participants who reported cannabis intake for medical use. CONCLUSION: This preliminary study characterized the profile of patients undergoing dental treatment in relation to marijuana use. Diminishing restraints to cannabis use may affect the dental profession. CLINICAL SIGNIFICANCE: It is important for dentists to understand cannabis-related oral health conditions to provide customized patient treatments.


Asunto(s)
Cannabidiol , Cannabis , Fumar Marihuana , Marihuana Medicinal , Adulto , Humanos , Femenino , Masculino , Adolescente , Adulto Joven , Persona de Mediana Edad , Marihuana Medicinal/uso terapéutico , Hospitales Generales , Fumar Marihuana/efectos adversos , Analgésicos
10.
Cytokine ; 137: 155342, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33130337

RESUMEN

BACKGROUND: The developing field of osteoimmunology supports importance of an interferon (IFN) response pathway in osteoblasts. Clarifying osteoblast-IFN interactions is important because IFN is used as salvage anti-tumor therapy but systemic toxicity is high with variable clinical results. In addition, osteoblast response to systemic bursts and disruptions of IFN pathways induced by viral infection may influence bone remodeling. ZIKA virus (ZIKV) infection impacts bone development in humans and IFN response in vitro. Consistently, initial evidence of permissivity to ZIKV has been reported in human osteoblasts. HYPOTHESIS: Osteoblast-like Saos-2 cells are permissive to ZIKV and responsive to IFN. METHODS: Multiple approaches were used to assess whether Saos-2 cells are permissive to ZIKV infection and exhibit IFN-mediated ZIKV suppression. Proteomic methods were used to evaluate impact of ZIKV and IFN on Saos-2 cells. RESULTS: Evidence is presented confirming Saos-2 cells are permissive to ZIKV and support IFN-mediated suppression of ZIKV. ZIKV and IFN differentially impact the Saos-2 proteome, exemplified by HELZ2 protein which is upregulated by IFN but non responsive to ZIKV. Both ZIKV and IFN suppress proteins associated with microcephaly/pseudo-TORCH syndrome (BI1, KI20A and UBP18), and ZIKV induces potential entry factor PLVAP. CONCLUSIONS: Transient ZIKV infection influences osteoimmune state, and IFN and ZIKV activate distinct proteomes in Saos-2 cells, which could inform therapeutic, engineered, disruptions.


Asunto(s)
Antivirales/inmunología , Interferón Tipo I/inmunología , Osteoblastos/inmunología , Infección por el Virus Zika/inmunología , Virus Zika/inmunología , Animales , Antivirales/farmacología , Línea Celular Tumoral , Chlorocebus aethiops , Regulación de la Expresión Génica/efectos de los fármacos , Regulación de la Expresión Génica/inmunología , Interacciones Huésped-Patógeno/efectos de los fármacos , Interacciones Huésped-Patógeno/inmunología , Humanos , Interferón Tipo I/farmacología , Ratones Noqueados , Osteoblastos/metabolismo , Osteoblastos/virología , Proteoma/inmunología , Proteoma/metabolismo , Proteómica/métodos , Células Vero , Replicación Viral/efectos de los fármacos , Replicación Viral/inmunología , Virus Zika/fisiología , Infección por el Virus Zika/metabolismo , Infección por el Virus Zika/virología
11.
J Oral Maxillofac Surg ; 79(1): 109-132.e6, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32800758

RESUMEN

PURPOSE: Several animal models of temporomandibular joint ankylosis (TMJA) have been described for more than the past 2 decades. The aim of this study was 2-fold: 1) to compile and summarize the evidence of animal studies that compare different forms to induce, treat (disease already established), or prevent (after trauma) TMJA; and 2) to address the following focused question: what is the quality of reporting in these studies? MATERIALS AND METHODS: A systematic review was conducted. Animal studies conducted up to October 2019 comparing at least 2 procedures to induce, treat (disease already established), or prevent (after trauma) TMJA were considered. Compliance with the Animal Research Reporting In Vivo Experiments guidelines was checked for all studies. Studies evaluating treatment of TMJA or preventive measures also were evaluated using the SYstematic Review Center for Laboratory animal Experimentation's risk of bias tool for animal studies. RESULTS: A total of 24 studies were included. The studies were evaluated for feasibility regarding data synthesis, and a meta-analysis was not suitable because of methodological differences, mainly regarding the animal model chosen and surgical procedures performed to induce TMJA. In 17 articles, authors aimed to investigate different procedures to induce TMJA (fibrous, fibro-osseous, or bony). In 7 articles, different treatment or preventive strategies were compared. The sheep was the most used animal in models of TMJA. Only 25% (6 of 24) of studies reported some step to minimize bias (ie, blinding of investigators, randomization procedures, or allocation concealment). Approximately 54% (13 of 24) of articles clearly commented on study limitations and potential sources of bias. Further animal studies on TMJA should consider improving their reporting standards to increase their validity and improve the reproducibility of animal experiments.


Asunto(s)
Anquilosis , Trastornos de la Articulación Temporomandibular , Animales , Anquilosis/prevención & control , Anquilosis/cirugía , Artroplastia , Reproducibilidad de los Resultados , Ovinos , Articulación Temporomandibular/cirugía , Trastornos de la Articulación Temporomandibular/prevención & control , Trastornos de la Articulación Temporomandibular/cirugía
12.
Lasers Med Sci ; 34(3): 537-546, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30259335

RESUMEN

Perform a physicochemical and morphological characterization of a Ti-15Mo alloy surface modified by laser beam irradiation and to evaluate in vitro the morphological response and proliferation of osteoblastic cells seeded onto this alloy. Disks were made of two different metals, Ti-15Mo alloy and cpTi, used as control. A total of four groups were evaluated: polished cpTi (cpTi-pol), laser-irradiated cpTi (cpTi-L), polished Ti-15Mo alloy (Ti-15Mo-pol), and laser-irradiated Ti-15Mo alloy (Ti-15Mo-L). Before and after laser irradiation of the surfaces, physicochemical and morphological analyses were performed: scanning electron microscopy (FEG-SEM), energy-dispersive spectroscopy (EDX), and X-ray diffraction (XRD). The wettability of the samples was evaluated by contact angle measurement. Murine preosteoblastic cells MC3T3-E1 were cultured onto the experimental disks for cell proliferation, morphology, and spreading analyses. Laser groups presented irregular-shaped cavities on its surface and a typical microstructured surface with large depressions (FEG-SEM). The contact angle for both laser groups was 0°, whereas for the polished groups was ≈ 77 and ≈ 78 for cpTi-pol and Ti-15Mo-pol, respectively. Cell proliferation analysis demonstrated a higher metabolic activity in the laser groups (p < 0.05). From the fluorescence microscopy, Ti-15Mo-L surface seems to induce greater cellular differentiation compared to the cpTi-L surface. The preliminary biological in vitro analyses suggested possible advantages of laser surface treatment in the Ti-15Mo alloy regarding cell proliferation and maturation.


Asunto(s)
Aleaciones/química , Aleaciones/farmacología , Rayos Láser , Animales , Línea Celular , Proliferación Celular/efectos de los fármacos , Proliferación Celular/efectos de la radiación , Forma de la Célula/efectos de los fármacos , Forma de la Célula/efectos de la radiación , Fluorescencia , Ratones , Microscopía Electrónica de Rastreo , Espectrometría por Rayos X , Propiedades de Superficie , Difracción de Rayos X
13.
J Oral Maxillofac Surg ; 75(5): 1004.e1-1004.e9, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28137635

RESUMEN

PURPOSE: To investigate the influence of different materials and fixation methods on maximum principal stress (MPS) and displacement in reconstruction plates using in silico 3-dimensional finite element analysis (3D-FEA). MATERIALS AND METHODS: Computer-assisted designed (CAD) models of the mandible and teeth were constructed. Champy and AO/ASIF plates and fixation screws were designed with CAD software. 3D-FEA was performed by image-based CAE software. Maximum and minimum values of biomechanical stability, MPS, and displacement distribution were compared in Champy and AO/ASIF plates made from commercially pure titanium grade 2 (cp-Ti) and a titanium-and-molybdenum (14.47% wt) alloy (Ti-15Mo). RESULTS: For plates fixed on a model of a fractured left angle of the mandible, the maximum and minimum values of MPS in the cp-Ti-constructed Champy plate, upper AO/ASIF plate, and lower AO/ASIF plate were 19.5 and 20.3%, 15.2 and 25.3%, and 21.4 and 4.6% lower, respectively, than those for plates made from Ti-15Mo. In the same model, the maximum and minimum values of displacement in the cp-Ti-constructed Champy plate, upper AO/ASIF plate, and lower AO/ASIF plate were 1.6 and 3.8%, 3.1 and 2.7%, and 5.4 and 10.4% higher, respectively, than those for plates made from Ti-15Mo. CONCLUSIONS: This in silico 3D-FEA shows that Ti-15Mo plates have greater load-bearing capability.


Asunto(s)
Placas Óseas , Simulación por Computador , Fracturas Mandibulares/cirugía , Titanio , Fenómenos Biomecánicos , Humanos , Procedimientos Ortopédicos/métodos , Procedimientos de Cirugía Plástica/métodos
14.
J Craniofac Surg ; 25(6): 2246-50, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25340696

RESUMEN

The aim of this study was to perform a physicochemical and morphological characterization and compare the mechanical behavior of an experimental Ti-Mo alloy to the analogous metallic Ti-based fixation system, for mandibular angle fractures. Twenty-eight polyurethane mandibles were uniformly sectioned on the left angle. These were divided into 4 groups: group Eng 1P, one 2.0-mm plate and 4 screws 6 mm long; group Eng 2P, two 2.0-mm plates, the first fixed with 4 screws 6 mm long and the second with 4 screws 12 mm long. The same groups were created for the Ti-15Mo alloy. Each group was subjected to linear vertical loading at the first molar on the plated side in a mechanical testing unit. Means and standard deviations were compared with respect to statistical significance using ANOVA. The chemical composition of the Ti-15Mo alloy was close to the nominal value. The mapping of Mo and Ti showed a homogeneous distribution. SEM of the screw revealed machining debris. For the plates, only the cpTi plate undergoes a surface treatment. The metallographic analysis reveals granular microstructure, from the thermomechanical trials. A statistically significant difference was found (P < 0.05) when the comparison between both internal fixation techniques was performed. The 2P technique showed better mechanical behavior than 1P.


Asunto(s)
Placas Óseas , Fijación Interna de Fracturas/instrumentación , Fracturas Mandibulares/cirugía , Modelos Anatómicos , Poliuretanos/química , Aleaciones/química , Fenómenos Biomecánicos , Tornillos Óseos , Análisis del Estrés Dental/instrumentación , Diseño de Equipo , Humanos , Ácido Fluorhídrico/química , Ensayo de Materiales , Microscopía Electrónica de Rastreo , Ácido Nítrico/química , Espectrometría por Rayos X , Estrés Mecánico , Propiedades de Superficie , Titanio/química
15.
Arch Oral Biol ; 159: 105875, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38160519

RESUMEN

OBJECTIVE: To assess the outcomes of several rodent animal models for studying tooth extraction-related medication-related osteonecrosis of the jaw (MRONJ). DESIGN: After a search of the databases, 2004 articles were located, and 118 corroborated the inclusion factors (in vivo studies in rodents evaluating tooth extraction as a risk factor for the development of MRONJ). RESULTS: Numerous studies attempting to establish an optimal protocol to induce MRONJ were found. Zoledronic acid (ZA) was the most used drug, followed by alendronate (ALN). Even when ZA did not lead to the development of MRONJ, its effect compromised the homeostasis of the bone and soft tissue. The association of other risk factors (dexamethasone, diabetes, and tooth-related inflammatory dental disease) besides tooth extraction also played a role in the development of MRONJ. In addition, studies demonstrated a relationship between cumulative dose and MRONJ. CONCLUSIONS: Both ZA and ALN can lead to MRONJ in rodents when equivalent human doses (in osteoporosis or cancer treatment) are used. Local oral risk factors and tooth-related inflammatory dental disease increase the incidence of MRONJ in a tooth extraction-related rodent model.


Asunto(s)
Osteonecrosis de los Maxilares Asociada a Difosfonatos , Conservadores de la Densidad Ósea , Animales , Humanos , Difosfonatos/efectos adversos , Conservadores de la Densidad Ósea/efectos adversos , Osteonecrosis de los Maxilares Asociada a Difosfonatos/etiología , Roedores , Ácido Zoledrónico/efectos adversos , Extracción Dental/efectos adversos , Modelos Animales , Alendronato/efectos adversos
16.
Plast Reconstr Surg Glob Open ; 12(7): e5952, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38957726

RESUMEN

Background: Lipedema is the progressive symmetrical deposition of subcutaneous fat and fluid in the lower body, ordinarily sparing the trunk, upper limbs, face, and neck. It may follow an autosomal dominant inheritance pattern. The gold standard treatment for lipedema is complete decongestive therapy, consisting of manual lymphatic drainage and compression garments. This scoping review assessed the existing literature on the effectiveness of liposuction as an alternative treatment for lipedema. Methods: A scoping review of electronically available literature within PubMed, Scopus, and Cochrane focused on liposuction as a treatment for lipedema considering the following inclusion criteria: human studies, case series of 10 or more, controlled trials, randomized controlled trials, patient-reported outcome measurement studies, survey analyses, descriptive studies, retrospective analyses, recurrence included, follow-up of 6 months or more, age 18 years or older, and treatment modality being liposuction. Results: Thirteen studies were selected. Nine studies reported decreased compression therapy use among patients following liposuction. No studies reported a long-term increase in compression therapy following liposuction. Studies found self-reported improvements in pain, mobility, bruising, and overall quality of life for patients following liposuction, many of whom had previously been on compressive therapy. Studies reported low rates of serious adverse events following liposuction, including deep vein thrombosis, pulmonary embolism, and infection. Conclusions: These results suggest that liposuction can be a viable treatment alternative to compression therapy for lipedema in patients whose compression therapy has not been helpful. However, there is not enough evidence to say whether liposuction is as effective as compression for patients first presenting with lipedema.

17.
J Funct Biomater ; 15(6)2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38921522

RESUMEN

OBJECTIVES: This study investigated a novel strategy for improving regenerative cartilage outcomes. It combines fractional laser treatment with the implantation of neocartilage generated from autologous dynamic Self-Regenerating Cartilage (dSRC). METHODS: dSRC was generated in vitro from harvested autologous swine chondrocytes. Culture was performed for 2, 4, 8, 10, and 12 weeks to study matrix maturation. Matrix formation and implant integration were also studied in vitro in swine cartilage discs using dSRC or cultured chondrocytes injected into CO2 laser-ablated or mechanically punched holes. Cartilage discs were cultured for up to 8 weeks, harvested, and evaluated histologically and immunohistochemically. RESULTS: The dSRC matrix was injectable by week 2, and matrices grew larger and more solid with time, generating a contiguous neocartilage matrix by week 8. Hypercellular density in dSRC at week 2 decreased over time and approached that of native cartilage by week 8. All dSRC groups exhibited high glycosaminoglycan (GAG) production, and immunohistochemical staining confirmed that the matrix was typical of normal hyaline cartilage, being rich in collagen type II. After 8 weeks in cartilage lesions in vitro, dSRC constructs generated a contiguous cartilage matrix, while isolated cultured chondrocytes exhibited only a sparse pericellular matrix. dSRC-treated lesions exhibited high GAG production compared to those treated with isolated chondrocytes. CONCLUSIONS: Isolated dSRC exhibits hyaline cartilage formation, matures over time, and generates contiguous articular cartilage matrix in fractional laser-created microenvironments in vitro, being well integrated with native cartilage.

18.
J Oral Maxillofac Surg ; 71(2): e69-75, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23351770

RESUMEN

PURPOSE: The present study evaluated the effect of different drilling dimensions (undersized, regular, and oversized) in the insertion and removal torques of dental implants in a beagle dog model. METHODS: Six beagle dogs were acquired and subjected to bilateral surgeries in the radii 1 and 3 weeks before euthanasia. During surgery, 3 implants, 4 mm in diameter by 10 mm in length, were placed in bone sites drilled to 3.2 mm, 3.5 mm, and 3.8 mm in final diameter. The insertion and removal torque was recorded for all samples. Statistical analysis was performed by paired t tests for repeated measures and by t tests assuming unequal variances (all at the 95% level of significance). RESULTS: Overall, the insertion torque and removal torque levels obtained were inversely proportional to the drilling dimension, with a significant difference detected between the 3.2 mm and 3.5 mm relative to the 3.8 mm groups (P < 0.03). Although insertion torque-removal torque paired observations was statistically maintained for the 3.5 mm and 3.8 mm groups, a significant decrease in removal torque values relative to insertion torque levels was observed for the 3.2 mm group. A different pattern of healing and interfacial remodeling was observed for the different groups. CONCLUSIONS: Different drilling dimensions resulted in variations in insertion torque values (primary stability) and stability maintenance over the first weeks of bone healing.


Asunto(s)
Implantación Dental Endoósea/métodos , Implantes Dentales , Retención de Prótesis Dentales , Animales , Fenómenos Biomecánicos , Implantación Dental Endoósea/instrumentación , Diseño de Prótesis Dental , Perros , Masculino , Modelos Animales , Oseointegración/fisiología , Osteotomía/instrumentación , Estrés Mecánico , Propiedades de Superficie , Tibia/cirugía , Factores de Tiempo , Torque
19.
Lancet Healthy Longev ; 4(4): e166-e175, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-37003275

RESUMEN

Periodontitis results from dysbiosis of the oral microbiome and affects up to 70% of US adults aged 65 years and older. More than 50 systemic inflammatory disorders and comorbidities are associated with periodontitis, many of which overlap with immunotherapy-associated toxicities. Despite the increasing use of immunotherapy for the treatment of cancer, uncertainty remains as to whether the microbial shift associated with periodontal disease can influence response rates and tolerance to cancer immunotherapy. We herein review the pathophysiology of periodontitis and the local and systemic inflammatory conditions related to oral dysbiosis, and discuss the overlapping adverse profiles of periodontitis and immunotherapy. The effects of the presence of Porphyromonas gingivalis, a key pathogen in periodontitis, highlight how the oral microbiome can affect the hosts' systemic immune responses, and further research into the local and systemic influence of other microorganisms causing periodontal disease is necessary. Addressing periodontitis in an ageing population of people with cancer could have potential implications for the clinical response to (and tolerability of) immunotherapy and warrants further investigation.


Asunto(s)
Neoplasias , Enfermedades Periodontales , Periodontitis , Humanos , Disbiosis , Periodontitis/epidemiología , Periodontitis/terapia , Porphyromonas gingivalis , Neoplasias/complicaciones , Neoplasias/terapia , Inmunoterapia/efectos adversos
20.
Artículo en Inglés | MEDLINE | ID: mdl-36241596

RESUMEN

OBJECTIVES: Mesenchymal stem/progenitor cells (MSPCs) are critical for tissue regeneration. Moreover, the CD105 antigen identifies early MSPCs with increased chondrogenic differentiation ability. We hypothesized that amine-(NH2)-functionalized biosilica incorporating hydrogel scaffolds, seeded with mCoSPCs105+ would contribute to creating tissue-engineered scaffolds, capable of de novo cartilage synthesis. MATERIALS AND METHODS: Scaffolds were characterized by water uptake, lysozyme degradation, axial compression, scanning electron microscopy, and energy-dispersive X-ray spectroscopy. Differentiation stimulus of scaffold functionalization was evaluated using Alcian blue staining. Cartilage-forming abilities of mCoSPCs105+ were evaluated using Quantitative reverse transcription polymerase chain reaction (qRT-PCR) and immunohistochemistry. RESULTS: Biosilica particle incorporation into scaffolds resulted in increased water uptake capacity and compression force withstanding abilities. Amine-(NH2)-group functionalization of biosilica led to significantly increased stem cell differentiation potential, by Alcian blue staining, in the first 3 weeks. Scaffold attachment and viable cell proliferation were observed for 6 weeks under chondrogenic differentiation. Downregulation of Runx2, an increase of Col10a1, Ihh, and maintenance of Sox9, was seen under these culture conditions. mCoSPCs105+ gene expression pattern was defined by the significant upregulation of Col1a1, Col2a1, Prg4, and Agc-1 over 6 weeks of incubation compared to the unsorted control. Immunostaining of cell-seeded scaffolds revealed significantly higher secretion of proteins relevant to cartilage extracellular matrix. CONCLUSION: The preselecting of CD105+ phenotype in MSPCs may enhance tissue regeneration of fibrocartilage and biosilica nanoparticles may be a beneficial additive in tissue engineering of scaffolds.


Asunto(s)
Hidrogeles , Células Madre Mesenquimatosas , Ratones , Animales , Hidrogeles/química , Hidrogeles/metabolismo , Azul Alcián/metabolismo , Diferenciación Celular , Andamios del Tejido/química , Ingeniería de Tejidos , Células Madre Mesenquimatosas/metabolismo , Condrogénesis , Células Cultivadas
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