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1.
Dent J (Basel) ; 8(2)2020 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-32260114

RESUMEN

Regenerative dentistry represents a novel interdisciplinary approach involving biomaterials, several molecules and mesenchymal stem cells (MSCs), preferably derived from oral tissues. The pivotal role of MSCs depends on the fact that they can differentiate into different cell lineages and have the strategic role to release bioactive substances that stimulate the renewal and regeneration of damaged tissues. The role of regenerative dentistry is promising in all the branches of dentistry: the most intriguing application is related to the management of endodontic and periodontal defects, overcoming the surgical approach and the implantology as a consequence of a poorly efficient therapeutic plan.

2.
Artículo en Inglés | MEDLINE | ID: mdl-32231082

RESUMEN

Peri-implant soft tissues play a role of paramount importance, not only on the esthetic appearance, but also on the maintenance and long-term stability of implants. The present report presents the conclusions from the Consensus Conference of the South European North African Middle Eastern Implantology & Modern Dentistry Association (SENAME) (4-6 November 2016, Cairo, Egypt). The conference focused on the topic of the soft tissue around dental implants, and in particular, on the influence of implant configurations on the marginal soft tissues, soft tissue alterations after immediate, early or delayed implant placement and immediate loading, the long-term outcomes of soft tissue stability around dental implants, and soft tissue augmentation around dental implants. Thirty world experts in this field were invited to take part in this two-day event; however, only 29 experts were in the final consensus voting process.


Asunto(s)
Implantes Dentales , Mucosa Bucal , Consenso , Egipto , Humanos
3.
Polymers (Basel) ; 12(2)2020 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-32033310

RESUMEN

Resin-based composites are widely used as dental restorative materials due to their excellent properties. They must have high modulus, high hardness, and be chemically inert while minimizing moisture uptake. To fulfill these higher standard prerequisites and properties, continuous improvements in each of their components are required. This study develops novel composites with multiple biofunctions. Light-cured Bis-GMA/TEGDMA dental resin (RK)/layered double hydroxide intercalated with fluoride ions (LDH-F)/calcium bentonite (Bt) hybrid composites were prepared. The loading ratio of LDH-F to Bt was varied, ranging from 2.5/2.5 to 10/10 parts per hundred RK and structural, mechanical, and biological properties were studied. The incorporation of even small mass fractions (e.g., 2.5 wt % of LDH-F and 2.5 wt % of Bt) in RK dental resin significantly improved the mechanical properties of the pristine resin. The synthetized materials showed antibacterial and antibiofilm effects against three bacterial strains isolated from healthy volunteers' saliva (Streptococcus spp., Bacteroides fragilis, and Staphylococcus epidermidis) without affecting its ability to induce dental pulp stem cells differentiation into odontoblast-like cells. The capability to balance between the antibiofilm activity and dental pulp stem cells differentiation in addition with improved mechanical properties make these materials a promising strategy in preventive and restorative dentistry.

4.
Clin Oral Investig ; 24(2): 1013-1023, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31286260

RESUMEN

OBJECTIVES: To assess dimensional changes following alveolar ridge preservation using bovine-derived xenograft with 10% collagen and collagen membrane compared to ridge preservation by means of bovine-derived xenograft particles and collagen membrane or spontaneous healing in posterior sites. MATERIALS AND METHODS: Forty subjects with 40 posterior teeth or roots candidate to extraction and presenting integrity of alveolar bone walls were randomly allocated into three groups. Patients of test group were treated by ridge preservation technique using bovine-derived xenograft with 10% collagen and collagen membrane; patients of control group 1 were treated by means of bovine-derived xenograft particles and collagen membrane while in patients of control group 2, no grafting was performed. Changes in vertical and horizontal bone dimensions were compared at baseline and after 6-month observation time. RESULTS: Statistically significant differences between baseline and 6 month were observed in all groups in terms of vertical and horizontal bone resorption (p < 0.001), except for vertical resorption in control group 2. After 6-month intergroup comparisons showed not statistically significant changes between test and control groups in terms of alveolar bone changes (p > 0.05). CONCLUSIONS: Within the limits of this study, the sites grafted using bovine-derived xenograft with 10% collagen in combination with a collagen membrane showed no statistical differences in terms of vertical and horizontal bone resorption compared to control groups. CLINICAL RELEVANCE: Ridge preservation in posterior area failed to show clinically relevant benefits in sites presenting integrity of alveolar bone walls and adequate buccal bone wall thickness.


Asunto(s)
Pérdida de Hueso Alveolar , Proceso Alveolar , Aumento de la Cresta Alveolar , Animales , Bovinos , Colágeno , Xenoinjertos , Humanos , Extracción Dental , Alveolo Dental
5.
Int J Oral Implantol (Berl) ; 12(4): 399-416, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31781696

RESUMEN

PURPOSE: To analyse and compare the dimensional changes of unassisted extraction sockets with alveolar ridge preservation (ARP) techniques and investigate any factors that impact the resorption of the alveolar bone. MATERIALS AND METHODS: A systematic search was conducted to identify randomised clinical trials (RCTs). All data were extracted, and a meta-analysis was performed for the changes in all buccolingual ridge width, midbuccal and midlingual ridge height, and mesial and distal ridge height, and horizontal width at reference points apical to the crestal area. RESULTS: Based on 14 RCTs, the effectiveness of ARP in reducing the dimensions of the postextraction alveolar socket was confirmed. The clinical magnitude of this effect was 1.95 mm in the buccolingual ridge width, 1.62 mm in the midbuccal ridge height, and 1.26 mm on the midlingual ridge height. Additionally, 0.45 mm and 0.34 mm for mesial and distal ridge height, and 1.21 mm, and 0.76 mm for ridge width changes at points 3 and 5 mm apical to the crest were noted. Meta-regression analyses revealed that the reflection of flaps and primary wound coverage during ARP may have detrimental effects on bone remodelling, while no statistical significance was observed for any of the bone graft substitutes or the percentage of molar sockets. CONCLUSIONS: Regardless of the protocol, ARP can only minimise ridge resorption. ARP is most effective on horizontal ridge width, providing the most benefit coronally (approximating the crest), followed by the midbuccal ridge height.


Asunto(s)
Aumento de la Cresta Alveolar , Proceso Alveolar , Consenso , Ensayos Clínicos Controlados Aleatorios como Asunto , Extracción Dental , Alveolo Dental
6.
Open Dent J ; 12: 160-172, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29854014

RESUMEN

Background: Prosthetic precision can be affected by several variables, such as restorative materials, manufacturing procedures, framework design, cementation techniques and aging. Marginal adaptation is critical for long-term longevity and clinical success of dental restorations. Marginal misfit may lead to cement exposure to oral fluids, resulting in microleakage and cement dissolution. As a consequence, marginal discrepancies enhance percolation of bacteria, food and oral debris, potentially causing secondary caries, endodontic inflammation and periodontal disease. Objective: The aim of the present in vitro study was to evaluate the marginal and internal adaptation of zirconia and lithium disilicate single crowns, produced with different manufacturing procedures. Methods: Forty-five intact human maxillary premolars were prepared for single crowns by means of standardized preparations. All-ceramic crowns were fabricated with either CAD-CAM or heat-pressing procedures (CAD-CAM zirconia, CAD-CAM lithium disilicate, heat-pressed lithium disilicate) and cemented onto the teeth with a universal resin cement. Non-destructive micro-CT scanning was used to achieve the marginal and internal gaps in the coronal and sagittal planes; then, precision of fit measurements were calculated in a dedicated software and the results were statistically analyzed. Results: The heat-pressed lithium disilicate crowns were significantly less accurate at the prosthetic margins (p<0.05) while they performed better at the occlusal surface (p<0.05). No significant differences were noticed between CAD-CAM zirconia and lithium disilicate crowns (p>0.05); nevertheless CAD-CAM zirconia copings presented the best marginal fit among the experimental groups. As to the thickness of the cement layer, reduced amounts of luting agent were noticed at the finishing line, whereas a thicker layer was reported at the occlusal level. Conclusion: Within the limitations of the present in vitro investigation, the following conclusions can be drawn: the recorded marginal gaps were within the clinical acceptability irrespective of both the restorative material and the manufacturing procedures; the CAD-CAM processing techniques for both zirconia and lithium disilicate produced more consistent marginal gaps than the heat-pressing procedures; the tested universal resin cement can be safely used with both restorative materials.

7.
Exp Mol Med ; 50(3): 1, 2018 03 22.
Artículo en Inglés | MEDLINE | ID: mdl-29563495

RESUMEN

Several aspects of stem cell life are governed by epigenetic variations, such as DNA methylation, histone modifications, and chromatin remodeling. Epigenetic events are also connected with the impairment of stem cell functions. For example, during senescence, there are significant changes in chromatin organization that alter transcription. The MECP2 protein can bind methylated cytosines and contribute to regulating gene expression at one of the highest hierarchical levels. Researchers are particularly interested in this protein, as up to 90% of Rett syndrome patients have an MECP2 gene mutation. Nevertheless, the role of MECP2 in this disease remains poorly understood. We used a mouse model of Rett syndrome to evaluate whether residual MECP2 activity in neural stem cells (NSCs) induced the senescence phenomena that could affect stem cell function. Our study clearly demonstrated that the reduced expression of MECP2 is connected with an increase in senescence, an impairment in proliferation capacity, and an accumulation of unrepaired DNA foci. Mecp2 +/- NSCs did not cope with genotoxic stress in the same way as the control cells did. Indeed, after treatment with different DNA-damaging agents, the NSCs from mice with mutated Mecp2 accumulated more DNA damage foci (γ-H2AX+) and were more prone to cell death than the controls. Senescence in Mecp2 +/- NSCs decreased the number of stem cells and progenitors and gave rise to a high percentage of cells that expressed neither stem/progenitor nor differentiation markers. These cells could be senescent and dysfunctional.


Asunto(s)
Diferenciación Celular/fisiología , Células-Madre Neurales/patología , Síndrome de Rett/patología , Animales , Apoptosis/fisiología , Western Blotting , Ciclo Celular/fisiología , Proliferación Celular/fisiología , Células Cultivadas , Senescencia Celular/fisiología , Daño del ADN/fisiología , Reparación del ADN/fisiología , Modelos Animales de Enfermedad , Femenino , Inmunohistoquímica , Ratones , Células-Madre Neurales/metabolismo , Síndrome de Rett/metabolismo
8.
Materials (Basel) ; 11(4)2018 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-29584683

RESUMEN

Over the last three decades, it has been frequently reported that the properties of dental restorative composites cured with argon laser are similar or superior to those achieved with conventional halogen and light emitting diode (LED) curing units. Whereas laser curing is not dependent on the distance between the curing unit and the material, such distance represents a drawback for conventional curing units. However, a widespread clinical application of this kind of laser remains difficult due to cost, heavy weight, and bulky size. Recently, with regard to the radiation in the blue region of the spectrum, powerful solid-state lasers have been commercialized. In the current research, CAD (computer-aided design)/CAM (computer-aided manufacturing) assisted solid-state lasers were employed for curing of different dental restorative composites consisting of micro- and nanoparticle-reinforced materials based on acrylic resins. Commercial LED curing units were used as a control. Temperature rise during the photopolymerisation process and bending properties were measured. By providing similar light energy dose, no significant difference in temperature rise was observed when the two light sources provided similar intensity. In addition, after 7 days since curing, bending properties of composites cured with laser and LED were similar. The results suggested that this kind of laser would be suitable for curing dental composites, and the curing process does not suffer from the tip-to-tooth distance.

9.
Int J Periodontics Restorative Dent ; 37(5): e290-e296, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28817143

RESUMEN

The aim of this study was to evaluate the clinical remodeling of the alveolar socket following the application of bovine-derived xenograft collagen and collagen membrane compared to natural spontaneous healing during the first 6 months following tooth extraction. A total of 20 patients with 20 fresh alveolar sockets were randomly allocated into a test or control group. After a 6-month follow-up period, surgical reentry was performed and implants were placed. Significant statistical differences were recorded in terms of vertical and horizontal bone changes between the test and control groups. Within the limitations of this study, socket preservation procedures may provide more favorable conditions for subsequent implant placement.


Asunto(s)
Aumento de la Cresta Alveolar/métodos , Sustitutos de Huesos/uso terapéutico , Colágeno/uso terapéutico , Extracción Dental/efectos adversos , Alveolo Dental/cirugía , Adulto , Proceso Alveolar/patología , Proceso Alveolar/cirugía , Animales , Desarrollo Óseo , Bovinos , Implantación Dental Endoósea/métodos , Femenino , Xenoinjertos , Humanos , Masculino , Extracción Dental/métodos
10.
Quintessence Int ; 48(4): 315-324, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28294200

RESUMEN

OBJECTIVES: The aim of this study was to evaluate implant survival rate and to measure peri-implant bone changes in full-arch rehabilitations with immediate placement and immediate loading implants with platform switching and Morse taper connection, in addition to platelet-rich fibrin (PRF) and buccal bone augmentation, after 4 years of follow-up. METHOD AND MATERIALS: In this retrospective controlled study, patients who had been fully rehabilitated with immediate placement and immediate loading implants were evaluated 4 years post-loading. Implants with platform switching and Morse taper connections were used (In-Kone Universal System, Global D) and PRF and buccal bone augmentation were applied. The radiographic bone loss was calculated by subtracting the bone level at baseline (BLT0) from that at the 4-year follow-up (BLT4) in immediate and delayed implants. Measurements were made at the distal, mesial, vestibular, and oral sites of the implants and the deepest value was recorded. Implants placed in extraction sites and implants placed in healed sites were considered. A comparison between the groups was performed using the Mann-Whitney test. The implant survival rate was calculated using the Kaplan-Meier analysis. RESULTS: In total, 42 patients (28 females and 14 males; average age 55.8 years old, age range 45 to 77) were recruited to this study. A total of 334 implants were put in place (226 in the maxilla, 108 in the mandible). The implant survival rate was 97.8% for the maxilla and 98.1% for the mandible, 98.3% for immediate implants and 96.9% for delayed implants. No statistically significant differences (P > .05) in the mean radiographic bone loss (mBL) were observed when comparing the immediate and delayed implants and the anterior and posterior implants. Statistically significant differences were found in the mBL between the mandibular and maxilla implants in the vestibular (P = .01) and mesial (P = .001) sites. CONCLUSION: Within their limits, the present results suggest that rehabilitation with platform switching and taper connection implants, in addition to buccal bone augmentation and the use of PRF, can lead to predictable results.


Asunto(s)
Implantes Dentales , Carga Inmediata del Implante Dental/métodos , Arcada Edéntula/rehabilitación , Anciano , Pérdida de Hueso Alveolar/diagnóstico por imagen , Pérdida de Hueso Alveolar/cirugía , Diseño de Implante Dental-Pilar , Fracaso de la Restauración Dental , Femenino , Humanos , Masculino , Persona de Mediana Edad , Fibrina Rica en Plaquetas , Estudios Retrospectivos , Resultado del Tratamiento
11.
J Oral Sci ; 59(1): 87-91, 2017 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-28049968

RESUMEN

Studies have failed to identify the molecular mechanisms that regulate the genotoxic and cytotoxic effects of methacrylate resins, which are important in the biocompatibility of dental materials. Interleukin (IL)-6 has a crucial role in the control of acute-phase protein response during inflammation. In humans, the synthesis and release of two major acute-phase proteins, C-reactive protein and serum amyloid A, are regulated by IL-6. This study focused on IL-6 and activation of its receptors gp80 and gp130 in human gingival fibroblasts in order to assess the effects of the commercial acid resins Jet Kit, Unifast, and Duralay on control of inflammation.


Asunto(s)
Resinas Acrílicas/farmacología , Resinas Compuestas/farmacología , Receptor gp130 de Citocinas/genética , Regulación de la Expresión Génica/efectos de los fármacos , Encía/metabolismo , Interleucina-6/genética , Receptores de Interleucina-6/genética , Transcripción Genética/efectos de los fármacos , Células Cultivadas , Fibroblastos/metabolismo , Encía/citología , Humanos , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
12.
Minerva Stomatol ; 65(6): 368-377, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27416154

RESUMEN

BACKGROUND: The purpose of the present study was to assess the effect of concentration and temperature of sodium hypochlorite (NaOCl) with added surfactants and time of exposure on its penetration into human dentine. METHODS: Seventy-five extracted permanent maxillary anterior teeth with single canals were shaped by using ProTaper SX hand-operated instruments. Then teeth were sectioned perpendicular to their long axis. The crowns and apical thirds of all the teeth were removed. The remaining roots were processed into 4-mm-long blocks and stained overnight in crystal violet. One hundred fifty stained blocks were further split into halves and treated by six NaOCl-based solutions from different brands: three solutions added with surfactants (Hypoclean, H6, Chlor-Xtra) and their regular counterparts (5.25%, 6%, <%6NaOCl). The dentine blocks were exposed to the solutions for 2, 5, and 20 minutes at 20° C, 37° C, and 45° C, respectively. The depth of penetration of NaOCl was determined by bleaching of the stain and measured by light microscopy at magnifications of 20x and 40x. Statistical analysis was made by using two way ANOVA and by comparing groups two by two with t-test. RESULTS: The shortest penetration (130.80±1.92µm) was measured after incubation with 5.25%NaOCl for 2 minutes at 20° C; the highest penetration (375.40±3.05µm) was obtained with Chlor-Xtra for 20 minutes at 45° C. Temperature and exposure time had a significant direct relationship with penetration of sodium hypochlorites with lowered surface tension into dentinal tubules. CONCLUSIONS: The exposure time and temperature of sodium hypochlorite as well as the addition of surfactants may influence the penetration depth of irrigants into dentinal tubules.


Asunto(s)
Dentina/química , Irrigantes del Conducto Radicular/farmacocinética , Hipoclorito de Sodio/farmacocinética , Dentina/ultraestructura , Difusión , Humanos , Técnicas In Vitro , Concentración Osmolar , Distribución Aleatoria , Método Simple Ciego , Tensión Superficial , Tensoactivos/farmacología , Temperatura
13.
Biomed Res Int ; 2016: 8175284, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27294136

RESUMEN

The aim of this retrospective radiological study was to evaluate the variability of the mandibular anatomy in the presence and absence of teeth and to consider how it could influence implant planning. 187 mandibular CT DentaScans were selected from our department archive according to the inclusion criteria. The axial height, vertical height, angulation of the bone crest, and the bone available for ideal implant placement were measured. The analysis of the data shows that the mandible contour presents a constant degree of angulation. The variation of angulation in the absence of teeth was statistically significant only in the region between the canine and the first premolar and in that between the second premolar and the first molar. The difference between the crest height and the available distance to place the implant was greater in the region of the second molar while in the other regions the implant planning was made complex by postextraction resorption. Alveolar bone resorption after tooth loss can be considered as a risk factor for lingual cortical perforation during the insertion of an implant. To avoid potential intra/postoperative complications, 3D radiographic examination is recommended in order to study the mandibular anatomy and identify the risk areas.


Asunto(s)
Implantes Dentales/efectos adversos , Mandíbula/diagnóstico por imagen , Planificación de la Radioterapia Asistida por Computador , Adolescente , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Tomografía Computarizada por Rayos X , Diente/diagnóstico por imagen , Adulto Joven
15.
Artículo en Inglés | MEDLINE | ID: mdl-26509991

RESUMEN

The purpose of the present prospective randomized study was to evaluate the influence of Laser-Lok microtextured surface on soft tissue peri-implant parameters and esthetics around immediate, functionally loaded implants for single-tooth replacement in the esthetic zone. This study included 77 patients divided into two groups based on different implants used: the control group had BioHorizons tapered internal non-Laser-Lok-type implants (NLL; n = 39) and the test group had BioHorizons tapered internal Laser-Lok-type implants (LL; n = 39). Outcome measures were survival, radiographic marginal bone-level changes, soft tissue parameters, and esthetics. One implant was lost in the test group and one in the control group, for a total survival rate of 96.1% after 3 years. Radiographically, mean crestal bone loss ± standard deviation was 0.59 ± 0.27 mm in the LL group compared with 1.17 ± 0.31 mm in the NLL group. A mean gain in papilla level of 0.41 ± 0.34 mm and 0.17 ± 0.36 mm was observed in the LL and the NLL groups, respectively, while the level of the midfacial peri-implant mucosa remained stable in both groups with no statistically significant differences (0.08 ± 0.42 mm for the LL group vs 0.06 ± 0.36 mm for the NLL group). The mean probing depth values in the LL and NLL groups were 0.58 ± 0.2 mm and 1.89 ± 0.3 mm, respectively. Within the limitations of this study, it was demonstrated that the clinical and esthetic outcome of immediate functional loading was more favorable for LL implants than for NLL implants.


Asunto(s)
Implantación Dental Endoósea/métodos , Implantes Dentales de Diente Único , Encía/anatomía & histología , Anciano , Papila Dental/anatomía & histología , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Osteogénesis , Estudios Prospectivos , Radiografía Dental , Resultado del Tratamiento
16.
Biomed Res Int ; 2015: 369273, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26273612

RESUMEN

The aim of this study was to evaluate the effects of leukocyte- and platelet-rich fibrin (L-PRF) on the pain and soft tissue healing after tooth extractions. Twenty-six patients (9 males and 17 females) were treated with multiple extractions (2 to 8), with a total of 108 extractions. This was an exploratory single blinded randomized clinical trial with a split-mouth design. The pain after the surgery was assessed in each patient by the VAS scale (1 to 10) at intervals of 24-48-72-96 hours. The soft tissue healing was clinically evaluated at 3, 7, 14, and 21 days after surgery by the same examiner surgeon, using the modified Healing Index (4 to 12). The mean value of postextraction pain was 3.2 ± 0.3 in the experimental sides and 4.1 ± 0.1 in the control sides. After 7 days from the extractions, the values of modified Healing Index in the experimental and control groups were, respectively, 4.8 ± 0.6 and 5.1 ± 0.9. The use of L-PRF in postextraction sockets filling can be proposed as a useful procedure in order to manage the postoperative pain and to promote the soft tissue healing process, reducing the early adverse effects of the inflammation.


Asunto(s)
Plaquetas/fisiología , Fibrina/metabolismo , Leucocitos/fisiología , Plasma Rico en Plaquetas/fisiología , Cicatrización de Heridas/fisiología , Plaquetas/metabolismo , Femenino , Humanos , Leucocitos/metabolismo , Masculino , Persona de Mediana Edad , Boca/fisiología , Plasma Rico en Plaquetas/metabolismo , Extracción Dental/métodos
17.
J Appl Biomater Funct Mater ; 13(1): 43-60, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25199071

RESUMEN

AIM: The chemical-physical properties of novel and long-standing calcium silicate cements versus conventional pulp capping calcium hydroxide biomaterials were compared. METHODS: Calcium hydroxide-based (Calxyl, Dycal, Life, Lime-Lite) and calcium silicate-based (ProRoot MTA, MTA Angelus, MTA Plus, Biodentine, Tech Biosealer capping, TheraCal) biomaterials were examined. Calcium and hydroxyl ion release, water sorption, interconnected open pores, apparent porosity, solubility and apatite-forming ability in simulated body fluid were evaluated. RESULTS: All calcium silicate materials released more calcium. Tech Biosealer capping, MTA Plus gel and Biodentine showed the highest values of calcium release, while Lime-Lite the lowest. All the materials showed alkalizing activity except for Life and Lime-Lite. Calcium silicate materials showed high porosity values: Tech Biosealer capping, MTA Plus gel and MTA Angelus showed the highest values of porosity, water sorption and solubility, while TheraCal the lowest. The solubility of water-containing materials was higher and correlated with the liquid-to-powder ratio. Calcium phosphate (CaP) deposits were noted on materials surfaces after short aging times. Scant deposits were detected on Lime-Lite. A CaP coating composed of spherulites was detected on all calcium silicate materials and Dycal after 28 days. The thickness, continuity and Ca/P ratio differed markedly among the materials. MTA Plus showed the thickest coating, ProRoot MTA showed large spherulitic deposits, while TheraCal presented very small dense spherulites. CONCLUSIONS: calcium silicate-based cements are biointeractive (ion-releasing) bioactive (apatite-forming) functional biomaterials. The high rate of calcium release and the fast formation of apatite may well explain the role of calcium silicate biomaterials as scaffold to induce new dentin bridge formation and clinical healing.


Asunto(s)
Materiales Biocompatibles/química , Compuestos de Calcio/química , Hidróxido de Calcio/química , Cementos Dentales/química , Materiales de Recubrimiento Pulpar y Pulpectomía/química , Silicatos/química , Porosidad , Solubilidad
18.
J Med Case Rep ; 8: 398, 2014 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-25434857

RESUMEN

INTRODUCTION: The fusion of permanent teeth is a development anomaly of dental hard tissue. It may require a hard multidisciplinary approach with orthodontics, endodontics, surgery and prosthetics to solve aesthetic and functional problems. CASE PRESENTATION: A 20-year-old Caucasian man presented to our Department to solve a dental anomaly of his upper central incisors. An oral investigation revealed the fusion of his maxillary central incisors and dyschromia of right central incisor. Vitality pulp tests were negative for lateral upper incisors and left central incisor. Radiographic examinations showed a fused tooth with two separate pulp chambers, two distinct roots and two separate root canals. There were also periapical lesions of central incisors and right lateral incisor, so he underwent endodontic treatment. Six months later, OPT examination revealed persistence of the periapical radiolucency, so endodontic surgery was performed, which included exeresis of the lesion, an apicoectomy and retrograde obturation with a reinforced zinc oxide-eugenol cement (SuperEBA) Complete healing of the lesion was obtained six months postoperatively. Fused teeth crowns were separated and orthodontic appliances were put in place. When correct teeth position was achieved (after nine months), the anterior teeth were prosthetically rehabilitated. CONCLUSION: Many treatment options have been proposed in the literature to solve cases of dental fusion. The best treatment plan depends on the nature of the anomaly, its location, the morphology of the pulp chamber and root canal system, the subgingival extent of the separation line, and the patient compliance. Following an analysis of radiographical and clinical data, it was possible to solve our patient's dental anomaly with a multidisciplinary approach.


Asunto(s)
Anodoncia/terapia , Endodoncia , Incisivo/anomalías , Ortodoncia , Grupo de Atención al Paciente , Humanos , Masculino , Adulto Joven
19.
J Biomech ; 47(16): 3825-9, 2014 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-25468297

RESUMEN

This study aimed at investigating the effects of titanium implants and different configurations of full-arch prostheses on the biomechanics of edentulous mandibles. Reverse engineered, composite, anisotropic, edentulous mandibles made of a poly(methylmethacrylate) core and a glass fibre reinforced outer shell were rapid prototyped and instrumented with strain gauges. Brånemark implants RP platforms in conjunction with titanium Procera one-piece or two-piece bridges were used to simulate oral rehabilitations. A lateral load through the gonion regions was used to test the biomechanical effects of the rehabilitations. In addition, strains due to misfit of the one-piece titanium bridge were compared to those produced by one-piece cast gold bridges. Milled titanium bridges had a better fit than cast gold bridges. The stress distribution in mandibular bone rehabilitated with a one-piece bridge was more perturbed than that observed with a two-piece bridge. In particular the former induced a stress concentration and stress shielding in the molar and symphysis regions, while for the latter design these stresses were strongly reduced. In conclusion, prosthetic frameworks changed the biomechanics of the mandible as a result of both their design and manufacturing technology.


Asunto(s)
Bioingeniería , Prótesis Dental de Soporte Implantado , Mandíbula/fisiología , Porcelana Dental , Diseño de Prótesis Dental , Oro , Humanos , Aleaciones de Cerámica y Metal , Impresión Tridimensional , Prótesis e Implantes , Estrés Mecánico , Titanio
20.
Case Rep Dent ; 2014: 925019, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25140261

RESUMEN

Background. This case report describes the orthodontic treatment of a woman, aged 17 years, with a permanent dentition, brachyfacial typology, Angle Class I, with full impaction of two canines (13,33), and a severe ectopy of the maxillary left canine. Her main compliant was the position of the ectopic teeth. Methods. Straightwire fixed appliances, together with cantilever mechanics, were used to correct the impaired occlusion and to obtain an ideal torque control. Results and Conclusion. The treatment objectives were achieved in 26 months of treatment. The impactions were fully corrected with an optimal torque. The cantilever mechanics succeeded in obtaining tooth repositioning in a short lapse of time. After treatment, the dental alignment was stable.

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