Viability and Adhesion of Periodontal Ligament Fibroblasts on a Hydroxyapatite Scaffold Combined with Collagen, Polylactic Acid-Polyglycolic Acid Copolymer and Platelet-Rich Fibrin: A Preclinical Pilot Study.

Background: Conventional periodontal therapy relies on bone regeneration strategies utilizing scaffolds made of diverse materials, among which collagen, to promote cell adhesion and growth. Objective: To evaluate periodontal ligament fibroblast (HPdLF) cell adhesion and viability for periodontal regeneration purposes on hydroxyapatite scaffolds containing collagen (HAp-egg shell) combined with polylactic acid−polyglycolic acid copolymer (PLGA) and Platelet-Rich Fibrin (PRF). Methods: Four variations of the HAp-egg shell were used to seed HPdLF for 24 h and evaluate cell viability through a live/dead assay: (1) (HAp-egg shell/PLGA), (2) (HAp-egg shell/PLGA + collagen), (3) (HAp-egg shell/PLGA + PRF) and (4) (HAp-egg shell/PLGA + PRF + collagen). Cell adhesion and viability were determined using confocal microscopy and quantified using central tendency and dispersion measurements; significant differences were determined using ANOVA (p < 0.05). Results: Group 1 presented low cell viability and adhesion (3.70−10.17%); groups 2 and 3 presented high cell viability and low cell adhesion (group 2, 59.2−11.1%, group 3, 58−4.6%); group 4 presented the highest cell viability (82.8%) and moderate cell adhesion (45%) (p = 0.474). Conclusions: The effect of collagen on the HAp-egg shell/PLGA scaffold combined with PRF favored HPdLF cell adhesion and viability and could clinically have a positive effect on bone defect resolution and the regeneration of periodontal ligament tissue.

Elaboration and Biocompatibility of an Eggshell-Derived Hydroxyapatite Material Modified with Si/PLGA for Bone Regeneration in Dentistry.

Hydroxyapatite (HAp) is the most commonly used biomaterial in modern bone regeneration studies because of its chemical similarity to bone, biocompatibility with different polymers, osteoconductivity, low cost, and lack of immune response. However, to overcome the disadvantages of HAp, which include fragility and low mechanical strength, current studies typically focus on property modification through the addition of other materials. Objective. To develop and evaluate the biocompatibility of a HAp material extracted from eggshells and modified with silicon (Si) and poly(lactic-co-glycolic) acid (PLGA). Materials and Methods. An in vitro experimental study in which a HAp material prepared from eggshells was synthesized by wet chemical and conventional chemical precipitation. Subsequently, this material was reinforced with Si/PLGA using the freezing/lyophilization method, and then osteoblast cells were seeded on the experimental material (HAp/Si/PLGA). To analyse the biocompatibility of this composite material, scanning electron microscopy (SEM) and fluorescence confocal microscopy (FCM) techniques were used. PLGA, bovine bone/PLGA (BB/PLGA), and HAp/PLGA were used as controls. Results. A cellular viability of 96% was observed for the experimental HAp/Si/PLGA material as well as for the PLGA. The viability for the BB/PLGA material was 90%, and the viability for the HAp/PLGA was 86%. Cell adhesion was observed on the exterior surface of all materials. However, a continuous monolayer and the presence of filopodia were observed over both external and internal surface of the experimental materials. Conclusions. The HAp/Si/PLGA material is highly biocompatible with osteoblastic cells and can be considered promising for the construction of three-dimensional scaffolds for bone regeneration in dentistry.

Evaluación del efecto del plasma rico en plaquetas en diferentes tiempos y conce ntraciones sobre la viabilidad de fibroblastos de ligamento periodontal y osteoblastos / Evaluation of platelet-rich plasma effect at different times and concentrations on periodontal ligament fibroblast and osteoblast viability

Antecedentes: Los factores de crecimiento utilizados en salud se pueden obtener de una fuente autóloga de primera generación llamada plasma rico en plaquetas (PRP). La diversidad de protocolos para prepararlos genera resultados variables en cuanto al tiempo entre la activación del PRP y sus efectos sobre la proliferación y viabilidad celular. Objetivo: Evaluar proliferación y viabilidad celular de fibroblastos de ligamento periodontal y osteoblastos tratados con PRP en diferentes concentraciones y tiempos de aplicación. Métodos: Se cultivaron líneas celulares de fibroblastos y osteoblastos y se preparó el PRP de sangre venosa de un adulto sano mediante centrifugación, seguido de activación con CaCl2 al 10 %. El efecto sobre la proliferación de las líneas celulares tras la aplicación de PRP y plasma pobre en plaquetas al 1 %, al 3 % y al 5 % se evaluó a las 0, 12, 24, 48 y 72 horas después de su activación mediante MTS. El grupo control consistió en cultivos sin tratamiento. Los datos se analizaron mediante las pruebas de Chi cuadrado, Fischer y McNemar. Resultados: Se observó un aumento de la viabilidad en células tratadas con PRP 24 horas después de su activación en una concentración del 5%. El ensayo de viabilidad celular mostró diferencias estadísticamente significativas entre el grupo experimental y el grupo control (p = 0,05). Conclusión: Los cultivos de fibroblastos y osteoblastos mostraron una tendencia a mayor viabilidad 24 horas después de a la activación con PRP al 5 %.

Background : Growth factors used in health treatments can be obtained from a first-generation source called platelet-rich plasma. The variety of protocols to prepare PRP produces variable results regarding PRP activation time and its effects on cell proliferation and viability. Purpose: To evaluate proliferation and cell viability of periodontal ligament fibroblasts and osteoblasts stimulated with PRP in several concentrations and times after PRP activation. Methods: An in vitro study was carried out using periodontal ligament fibroblast and osteoblast cell cultures. PRP from venous blood of a healthy adult was prepared through centrifugation and activated with 10% CaCl2. The effect on cell proliferation after application of 1%, 3%, and 5% PRP and platelet-poor plasma was evaluated at 0, 12, 24, 48, and 72 hours after activation through MTS. The control group consisted of culture that did not receive any treatment. Data were analyzed using Chi square, Fisher, and McNemar tests. Results: The cell viability assay showed statistically significant differences between the experimental and the control groups. Cell viability increased in cells treated with 5% PRP 24 hours after activation (p = 0.05). Conclusions: Fibroblast and osteoblast cell lines tended to be more viable 24 hours after activation with 5% PRP.

Análisis mutacional del gen MSX1 en pacientes con FLPNS e hipodoncia / Mutation analysis of MSX1 gene in patients with NSCLP and hypodontia

Introducción. La etiología de la hendidura labio-palatina es compleja e involucra factores genéticos y ambientales. Además de la hendidura, numerosos estudios han reportado la presencia de anomalías dentales en asociación con varias formas de hendidura labial,palatina o ambas; entre estas anomalías se ha encontrado la prevalencia de agenesia dental. La idea de que los mismos factores etiológicos que causan la formación de la hendidura afectan el desarrollo de la dentición, es apoyada por varios autores que proponen al genMSX1 como candidato para estos dos fenotipos. Una mutación nonsense (Ser104stop) en el exon 1 del gen MSX1 se encontró en una familia danesa, en la que unos miembros presentaban agenesia dental o hendidura palatina y otros presentaban las dos entidadesasociadas. A pesar de que se han realizado varios estudios sobre anomalías dentales en pacientes con hendidura labio-palatina y existen estudios que confirman a MSX1 como ungen candidato tanto para hipodoncia como para hendiduras oro-faciales, la interpretación de los resultados ha sido muy compleja. Objetivo. Determinar la presencia de la mutación reportada en pacientes colombianos con hendidura labio-palatina e hipodoncia. Materiales y métodos. Se analizaron 30 pacientes, 22 con hendidura labio-palatina y 8 sólo con hipodoncia, y 60 controles sanos, mediante exámenes clínicos y radiográficos; se les tomaron muestras de sangre por venopunción, se extrajo el ADN y se realizó amplificación por la técnica de PCR del exón 1. Posteriormente, se llevó a cabo un análisis de restricción. Resultados. De los pacientes con hendidura labio-palatina, 16 presentaron agenesias dentalesfuera y dentro del área de hendidura, la mayoría fueron laterales y premolares superiores. La mayoría de los pacientes con hipodoncia únicamente, presentaron ausencias de incisivos. Además, presentaron otras anomalías dentarias, como micrognatismo, dientes supernumerarios y prognatismo mandibular...

Introduction: The etiology of non-syndromic cleft lip palate is complex and involves genetic and environmental factors. Additional to the fissure itself, numerous studies have reported the presence of dental anomalies with various forms of cleft lip, cleft palate or both. The prevalence of dental agenesis has been found within these anomalies. The idea that the same etiology factors which cause the formation of the cleft affect the dental development is supported by various authors who propose the MSX1 gene to be the candidate for these two phenotypes. A nonsense mutation in the exon 1 of the MSX1 gene was found in a Danish family in which one of the members presented dental agenesis and/or cleft palate and others presented both entities. Although various studies have been associated reported with respect to dental anomalies in patients with nonsyndromic cleft lip palate and there are studies which confirm MSX1 as a candidate gene for hypodontia and orofacial fissures, the interpretation of the results has been very complex.Objective: To determine the presence of the mutation reported in Colombian patients with nonsyndromic cleft lip palate and hypodontia. Materials and methods: 30 patients, 22 with non-syndromic cleft lip palate and 8 with only hypodontia and 60 healthy patients were clinically and radiographically analyzed. Blood samples were taken through venopunction, the DNA was extracted and the PCR technique was utilized. Afterwords, the restriction analysiswas carried out...