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1.
Nature ; 616(7957): 443-447, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36858073

RESUMEN

Although no known asteroid poses a threat to Earth for at least the next century, the catalogue of near-Earth asteroids is incomplete for objects whose impacts would produce regional devastation1,2. Several approaches have been proposed to potentially prevent an asteroid impact with Earth by deflecting or disrupting an asteroid1-3. A test of kinetic impact technology was identified as the highest-priority space mission related to asteroid mitigation1. NASA's Double Asteroid Redirection Test (DART) mission is a full-scale test of kinetic impact technology. The mission's target asteroid was Dimorphos, the secondary member of the S-type binary near-Earth asteroid (65803) Didymos. This binary asteroid system was chosen to enable ground-based telescopes to quantify the asteroid deflection caused by the impact of the DART spacecraft4. Although past missions have utilized impactors to investigate the properties of small bodies5,6, those earlier missions were not intended to deflect their targets and did not achieve measurable deflections. Here we report the DART spacecraft's autonomous kinetic impact into Dimorphos and reconstruct the impact event, including the timeline leading to impact, the location and nature of the DART impact site, and the size and shape of Dimorphos. The successful impact of the DART spacecraft with Dimorphos and the resulting change in the orbit of Dimorphos7 demonstrates that kinetic impactor technology is a viable technique to potentially defend Earth if necessary.

2.
J Esthet Restor Dent ; 36(3): 421-428, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38053482

RESUMEN

STATEMENT OF PROBLEM: The Vita Toothguide 3D-Master (Vita Zahnfabrik) is considered the dental shade guide in which the three dimensions of color - lightness, hue, and chroma - are most well-ordered in the CIELAB color space. No research has yet explored how well the Vita Toothguide 3D-Master is ordered in the 3D color space by recording color coordinates in vivo. PURPOSE: To evaluate the spatial color distribution of the Vita Toothguide 3D-Master's lightness, chroma, and hue groups and its 26 physical shade tabs. MATERIALS AND METHODS: The dental color (L*, C*, h°, a*, and b* color coordinates) of a healthy maxillary central incisor was recorded for 1361 participants (aged between 18 and 89 years) using a Vita Easyshade Compact spectrophotometer (Vita Zahnfabrik). The R 2.7.2. statistics program was used to create the visual representations. RESULTS: The five lightness levels are those that are best distributed in the color space, in relation to the L* coordinates, followed by the chroma group and, finally, the hue group. The 5M1, 5M2, and 5M3 physical shade tabs are situated at a greater distance apart from the other tabs in the color space. CONCLUSIONS: The Vita Toothguide 3D-Master's 26 physical shade tabs are satisfactorily distributed in three-dimensional space, although strict mathematical criteria are not followed. The natural dental shades that fall lower on the lightness scale are the most poorly represented by the physical shade tabs. CLINICAL IMPLICATIONS: Darker teeth are poorly represented by the Vita Toothguide 3D-Master's physical shade tabs. The spatial distribution of dental shade guides needs to be improved to ensure they provide homogeneous coverage of the entire chromatic spectrum corresponding to natural teeth. This would help reduce the errors inherent to the subjective visual color selection process.


Asunto(s)
Diseño de Prótesis Dental , Coloración de Prótesis , Humanos , Adolescente , Adulto Joven , Adulto , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años , Color , Coloración de Prótesis/métodos , Incisivo , Espectrofotometría
3.
Medicina (Kaunas) ; 58(3)2022 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-35334632

RESUMEN

Background and Objectives: To study the validity and the degree of representability of the toothguide 3D Master, with 26 physically shade tabs, on the natural tooth colour on a sample of the Spanish population. Materials and Methods: Natural tooth colour was measured in a sample of 1361 Spanish participants of both genders distributed within an age range of 18 and 89 years of age. The colour coordinates were calculated and the frequency of the 26 physically shade tabs of the toothguide as well as the "intermediate shades" (without physical representation in toothguide) through the Easyshade Compact (Vita-Zahnfabrik) spectrophotometer using the 3D Master System nomenclature. The colour differences between the "intermediate shades" were calculated using the Euclidean formula (ΔEab*). The program used for the present descriptive statistical analysis of the results was SAS 9.1.3. Results: A total of 49 "intermediate shades" were registered in 816 participants (60%). The colour coordinates of the 49 'intermediate shades' cover colour coordinates ranging from 0M1.5 (L* 100.0, C* 7.70, h* 112.2) to 5M2.5 (L* 56.8, C* 35.8, h* 78.5). Not all possible 3D Master System's "intermediate shades" were registered in the population studied. 82.4% of the colour differences among the "intermediate shades" were clinically unacceptable (ΔEab* ≥ 5.5 units). Conclusions: Only 40% of the population studied presented a natural tooth colour belonging to the 3D Master Toothguide's physical shade tabs.


Asunto(s)
Coloración de Prótesis , Diente , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Color , Recolección de Datos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Coloración de Prótesis/métodos , Espectrofotometría , Adulto Joven
4.
BMC Oral Health ; 21(1): 179, 2021 04 07.
Artículo en Inglés | MEDLINE | ID: mdl-33827530

RESUMEN

BACKGROUND: The aim of this study was to compare the influence of two novel reciprocating movements on the cyclic fatigue resistance of endodontic reciprocating files. METHODS: 30 Procodile® (Komet Medical, Lemgo, Germany) files were selected in this study and distributed according to the following study groups depending on the movements to be performed: ReFlex Dynamic (n = 10), ReFlex Smart (n = 10) and Reciproc (n = 10) reciprocating movement. These files were fixed to a specific dynamic cyclic fatigue device designed and manufactured by 3D impression to simulate the pecking motion performed by the operator. The time to failure and the number of cycles of in-and-out of the endodontic files was registered. The results were analyzed by ANOVA and Weibull statistics. RESULTS: Statistically significant differences were found when the number of cycles of in-and-out movement and the time to failure of ReFlex Dynamic and Reciproc reciprocating movement (p < 0.001) and between ReFlex Smart and Reciproc reciprocating movement (p < 0.001) were compared in pairs. However, no statistically significant differences were observed between time to failure and number of cycles of in-and-out movement of ReFlex Dynamic and ReFlex Smart reciprocating movement (p = 0.253). CONCLUSIONS: The ReFlex Smart reciprocating movement increased the cyclic fatigue resistance of endodontic reciprocating files compared with traditional reciprocating movement.


Asunto(s)
Preparación del Conducto Radicular , Titanio , Diseño de Equipo , Falla de Equipo , Alemania , Humanos , Ensayo de Materiales
5.
Rev Argent Microbiol ; 51(2): 130-135, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30017323

RESUMEN

In order to determine the presence and genetic diversity of Chlamydia spp. in the north-eastern area of Buenos Aires province, Argentina, conjunctival, oropharyngeal, cloacal swab and tissues were collected from a total of 90 psittacine pet birds of different age and clinical manifestations. Through molecular methods, Chlamydiaceae was detected in 30% (27/90) of the samples, out of which 70.3% (19/27) were positive for Chlamydia psittaci and 14.9% (4/27) for Chlamydia abortus. Nine C. psittaci positive samples were genotyped by ompA gene sequences, 8 clustered within genotype A and 1 within genotype B. A significant association was observed between the presence of Chlamydia spp. and the manifestation of clinical signs compatible with chlamydiosis, as well as with the age of the birds (younger than one year old). This report contributes to the improvement of our understanding of chlamydial agents in our country.


Asunto(s)
Enfermedades de las Aves/microbiología , Infecciones por Chlamydia/veterinaria , Chlamydia/genética , Chlamydia/aislamiento & purificación , Chlamydophila psittaci/genética , Chlamydophila psittaci/aislamiento & purificación , Mascotas/microbiología , Psittaciformes/microbiología , Psitacosis/veterinaria , Animales , Argentina , Infecciones por Chlamydia/microbiología , Genotipo , Psitacosis/microbiología
6.
J Korean Assoc Oral Maxillofac Surg ; 50(3): 161-165, 2024 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-38940653

RESUMEN

Peripheral ameloblastoma (PA) is believed to be the rarest variant of ameloblastoma and only has been described in isolated case reports. PA is usually confined to the soft tissues surrounding the supporting tissues of the teeth. Although it manifests nonaggressive behavior and can be treated with complete removal by local surgical excision, long term follow up is mandatory to prevent future recurrence and possible malignant transformation.

7.
Clin Implant Dent Relat Res ; 26(2): 442-456, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38282266

RESUMEN

INTRODUCTION: There is evidence that the apico-coronal implant position and the mucosal phenotype can affect the extent of peri-implant bone loss. This clinical trial analyzes the bone remodeling and marginal bone loss that occur around conical-connection implants placed equicrestally and subcrestally, assessing the effect of the peri-implant soft-tissue phenotype. METHODS: Fifty-one patients received 56 implants of distinct diameters (3.5 mm Ø n = 6; 4.3 mm Ø n = 41; 5 mm Ø n = 9) in the posterior part of the maxilla or mandible. The implants were placed equicrestally, 1 mm subcrestally and >1 mm subcrestally, depending on the initial supracrestal tissue height (STH). After 3 months of non-submerged healing, single metal-ceramic screw-retained implant-supported crowns were placed. Longitudinal measurements of STH, mucosal thickness and keratinized mucosa width (KMW) were made at the time of implant placement (T0), crown placement (T1), and after 3 (T2) and 6 months (T3) of prosthetic loading. At each of these points, a radiographic evaluation of bone remodeling and marginal bone loss was also performed. RESULTS: STH was significantly greater for implants placed >1 mm subcrestally than for those placed 1 mm subcrestally. After 12 months of follow-up, a very significant (p < 0.001) loss of KMW was observed, in addition to a marginal bone loss of 0.08 ± 0.1, 0.15 ± 0.2, and 0.14 ± 0.2 mm in the groups placed equicrestally, 1 mm subcrestally and >1 mm subcrestally, respectively. After the multiple linear regression, marginal bone loss was found to depend primarily on KMW (ß = -0.43), while also being affected by STH (ß = 0.32) and implant diameter (ß = -0.28). CONCLUSIONS: Marginal bone loss may be influenced by the position with respect to the bone crest, as well as the KMW, STH, and implant diameter. However, more well-controlled studies are needed to verify these above-mentioned findings with different implant designs and connections.


Asunto(s)
Pérdida de Hueso Alveolar , Implantes Dentales , Humanos , Pérdida de Hueso Alveolar/diagnóstico por imagen , Pérdida de Hueso Alveolar/etiología , Remodelación Ósea , Coronas , Implantación Dental Endoósea/efectos adversos , Implantación Dental Endoósea/métodos , Implantes Dentales/efectos adversos , Membrana Mucosa
8.
J Dent ; : 105264, 2024 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-39053878

RESUMEN

OBJECTIVES: To evaluate the bone changes around equicrestal and subcrestal implants, analyzing the effect of abutment height [short abutments (SA<2mm) and long abutments (LA>2mm)] and the three components of the peri-implant soft-tissue phenotype. METHODS: Twenty-six patients received 71 implants that were placed according to supracrestal tissue height (STH) in an equicrestal (n=17), shallow subcrestal ≈1mm (n=33), or deep subcrestal ≈2mm (n=21) position. After 3 months of healing, rehabilitation was completed using metal-ceramic crowns on multi-unit abutments of 1.5mm, 2.5mm, or 3.5mm in height, depending on the prosthetic space and STH. Longitudinal clinical parameters (STH, mucosal thickness, and keratinized mucosa width) and radiographic data [bone remodelling and marginal bone loss (MBL)] were collected at 3, 6, 12, and 24 months postsurgery. RESULTS: The gain in STH was significantly greater around the implants placed in a subcrestal ≈2mm position. After 2 years, the mean change in bone remodelling in the SA group was significantly greater than in the LA group. According to the multiple linear regression, bone remodelling depends primarily on abutment height (ß=-0.43), followed by crestal position (ß=0.34), and keratinized mucosa width (ß=-0.22), while MBL depends on abutment height (ß =-0.37), and the patient's age (ß =-0.36). CONCLUSIONS: Implants placed in an equicrestal or subcrestal ≈1mm position with LA undergo less bone remodelling, while the lowest level of MBL occurs in subcrestal ≈2mm implants with LA. Differing soft-tissue thicknesses combined with the use of either SA or LA produced significant intergroup differences in bone remodelling and MBL. CLINICAL SIGNIFICANCE: Abutment height is the most powerful predictor variable affecting bone remodelling and MBL. Depending on the dimensions of the peri-implant soft-tissue phenotype, placing the implants subcrestally may also be a viable option to decrease bone remodelling and, consequently, reduce MBL. CLINICAL TRIAL REGISTRATION: identification number: NCT05670340.

9.
Dent J (Basel) ; 12(7)2024 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-39056981

RESUMEN

The importance of augmenting the peri-implant soft- and hard-tissue architecture is now widely accepted. However, while most contemporary research supports this premise, clinicians are encountering peri-implant soft tissue defects with increasing frequency, which they are therefore required to reconstruct. These complications can result from the difficulty of establishing an appropriate diagnosis and treatment plan or from suboptimal clinical situations (implant malposition, insufficient vestibular alveolar bone thickness or inadequate mucosal thickness). In this context, it is the peri-implant soft-tissue phenotype that most influences esthetic and health-related results in the short and long term. This article describes two clinical cases in which a modification of the apical access technique is presented that may be useful in clinical scenarios requiring large gains in mucosal thickness. Use of the modified bilaminar apical access with de-epithelialized free gingival graft technique showed promising results, with a significant increase in mucosal thickness and satisfactory outcomes in esthetics and peri-implant health.

10.
Clin Rheumatol ; 42(5): 1259-1265, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36627527

RESUMEN

OBJECTIVES: A survey conducted by the Spanish Lupus Federation (FELUPUS) shows the results on perceptions and experiences of the people who live with lupus in Spain. The information was gathered anonymously from May 21st to June 30th, 2020. The aim of the study was to monitor the impact of the disease on quality of life, as well as to measure the impact of organ damage in lupus patients. METHODS: A national survey was conducted among people with lupus living in Spain who belong to the Spanish Lupus Patient Association (FELUPUS). Online interviews of approximately 25 min were completed. The information was gathered anonymously from May 21st to June 30th, 2020. RESULTS: One thousand two hundred sixty-three interviews were completed. 92% had a diagnosis of Systemic Lupus Erythematosus (SLE) and 8% of Cutaneous Lupus Erythematosus (CLE); 95% of the patients surveyed were female. Most of the patients claimed they stay up late, exercising and work/study were the most limited actions due to the disease. 73% of patients considered that there was little knowledge of the disease by society and at the time of diagnosis, the patient's level of knowledge about lupus was low in 92% of them. Regarding organ damage, many patients did not understand the concept of chronicity and irreversibility of the term, relating it erroneously to acute symptoms like fatigue (38%), joint pain (47%) and even to the presence of cutaneous symptoms such as the presence of oral ulcers (17%). CONCLUSIONS: The survey highlighted the need for disease awareness campaigns, greater involvement of healthcare professionals and the need to provide more information to lupus patients from the time of diagnosis. Nationally and to our knowledge, this is the survey with the largest number of participants (N = 1263) conducted in patients with lupus. Key Points •A national survey was conducted among people with lupus living in Spain and belonging to patient associations in Spain (FELUPUS). •Nationally and to our knowledge, this is the survey with the largest number of participants (N = 1263) conducted in patients with lupus. •Most of the patients claimed they stay up late, exercising and work/study were the most limited actions due to the disease. •73% of patients considered that there is little knowledge of the disease by society and at the time of diagnosis, the patient's level of knowledge about lupus was low in 92% of them.


Asunto(s)
Lupus Eritematoso Cutáneo , Lupus Eritematoso Sistémico , Humanos , Femenino , Masculino , Calidad de Vida , Lupus Eritematoso Sistémico/diagnóstico , Lupus Eritematoso Sistémico/complicaciones , Encuestas y Cuestionarios , Artralgia/complicaciones
11.
Artículo en Inglés | MEDLINE | ID: mdl-36089487

RESUMEN

OBJECTIVE: The objective of this study was to assess the mechanical characteristics and the clinical usefulness of beta-tricalcium phosphate (ß-TCP) and hydroxyapatite (HA) bioblocks grafted in edentulous jaws of 12 patients. METHODS: The scaffolds were produced by robocasting ceramic inks containing 80%/20% ß-TCP and HA, respectively, with an overall porosity of 60%, with a macropore size between 300 and 500 µm. The mechanical performance of cylindrical vs conical specimens was compared using a universal testing machine. The clinical study was performed on 12 edentulous patients who received 4 cylindrical bone bioblocks. After 10 to 16 weeks of osseointegration, the bioblocks were explanted with trephine for histologic analysis by Goldner and Von Kossa staining. RESULTS: Conical shapes were significantly stronger (96.4 ± 8.7 MPa) than cylindrical shapes (87.8 ± 12.2 MPa). The overall degree of porosity ranged from 53.4% to 58.1% in the coronal region to 62.5% to 66.9% at the apex. After the maturation period, 41 valid bioblocks (85.4%) were obtained for histologic study. Bone showing some cellularity was found in 68.4% of the samples, indicating biologically active bone, and adequate calcification was found in 31.7% of the samples. In terms of biomaterial degradation, 73.2% of the samples were completely resorbed or showed significant resorption. CONCLUSIONS: The 80%/20% ß-TCP and HA grafts customized by robocasting appear adequate for regenerating self-contained defects.


Asunto(s)
Sustitutos de Huesos , Procedimientos Quirúrgicos Orales , Humanos , Durapatita , Materiales Biocompatibles , Fosfatos de Calcio , Sustitutos de Huesos/uso terapéutico
12.
Int J Oral Maxillofac Implants ; 38(1): 120-129, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37099581

RESUMEN

Purpose: To examine how the accuracy (linear and angular deviation) of implants placed using computer-guided surgery varies in relation to the type of surgical technique (fully guided, half-guided, vs freehand implant placement), bone density (type D1 to D4 bone), and type of support surface (tooth- vs mucosa-supported). Materials and Methods: A total of 32 mandible models were produced (16 partially edentulous and 16 edentulous) using acrylic resin, each calibrated to a different bone density (D1 to D4). Four implants planned using Mguide software were placed in each acrylic resin mandible. A total of 128 implants were placed, distributed according to bone density (D1 to D4, n = 32), the degree of intervention in the surgery (fully guided [FG] = 80, half-guided [HG] = 32, and freehand surgery [F] = 16), and the type of support surface (tooth-supported: n = 64 and mucosa-supported: n = 64). To determine the linear, vertical, and angular deviations between the planned three-dimensional position and the actual position of the implants, the linear and angular difference between them was calculated, with the analysis performed through preoperative and postoperative CBCT scans. The effect was analyzed using parametric tests and linear regression models. Results: All parameters of linear and angular discrepancy in the various regions analyzed (neck, body, and apex) were primarily influenced by the technique and, to a lesser extent, by the bone type, although both variables were predictive and highly significant. These discrepancies tend to increase in completely edentulous models. The regression models show that linear deviations increase by between 630.2 µm at neck level in the buccolingual direction and 836.7 µm at apex level in the mesiodistal direction when comparing the FG and HG techniques. This increase is accumulative when comparing the HG and F techniques. Regarding the effect of bone density, the regression models found that linear discrepancies increase by between 132.6 µm in the axial direction and 199.0 µm at the apex of the implant in the buccolingual direction with each reduction in bone density (D1 to D4). Conclusion: According to this in vitro study, the highest implant placement predictability is found among dentate models with high bone density and a fully guided surgical technique.


Asunto(s)
Implantes Dentales , Boca Edéntula , Cirugía Asistida por Computador , Humanos , Implantación Dental Endoósea/métodos , Diseño Asistido por Computadora , Cirugía Asistida por Computador/métodos , Tomografía Computarizada de Haz Cónico , Resinas Acrílicas , Imagenología Tridimensional
13.
Artículo en Inglés | MEDLINE | ID: mdl-37338923

RESUMEN

Peri-implant soft tissue deformities are an increasingly common phenomenon in the esthetic zone. While the most widely studied esthetic complications are peri-implant soft tissue dehiscences, there are other esthetic concerns in routine clinical practice that require investigation and treatment. Thus, this report on two clinical cases describes a surgical approach using the apical access technique to treat peri-implant soft tissue discoloration and fenestration. In both clinical scenarios, the defect was accessed via a single horizontal apical incision without removing the cement-retained crowns. A bilaminar technique using apical access with a simultaneous connective tissue graft seems to offer promising results for the treatment of peri-implant soft tissue deformities. At the 12-month reevaluation, an increase in peri-implant soft tissue thickness was observed, resolving the pathologies presented.


Asunto(s)
Implantes Dentales de Diente Único , Implantes Dentales , Humanos , Implantación Dental Endoósea/efectos adversos , Implantación Dental Endoósea/métodos , Estética Dental , Coronas
14.
Int J Oral Maxillofac Implants ; 37(5): 1026-1036, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36170317

RESUMEN

PURPOSE: To analyze the quality of bone regeneration in fresh sockets using four different materials at different time points. MATERIALS AND METHODS: A split-mouth randomized clinical trial was designed to evaluate the histologic and histomorphometric characteristics of 82 fresh sockets from 30 patients. One socket per patient healed spontaneously (control), and at least one fresh socket was grafted with a material chosen randomly from a sealed envelope: plateletrich growth factor (PRGF; n = 20 sites), PRGF + autologous bone (n = 9 sockets), autologous bone (n = 10 sites), or PRGF + demineralized freeze-dried bone allograft (DFDBA; n = 13). Biopsy specimens were taken at different time points divided into three assessment groups: short duration (2 to 4 months), intermediate duration (5 to 6 months), and long duration (7 to 12 months). The histologic findings were assessed to quantify the trabeculae pattern, the degree of mineralization, and the quality of bone regeneration. RESULTS: A total of 26 patients with 73 sockets completed the study. Mineralization after a short duration was found to be significantly higher among sockets treated only with autologous bone (47.3% ± 3.6%) or with PRGF+autologous bone (45.1% ± 13.6%). During the intermediate time point, this difference was not observed; also, the control sites were found to have the highest amount of mineralization (37.7% ± 14.9%). After a long duration of wound healing, the PRGF+DFDBA group had the greatest percentage of mineralized tissue (54.7% ± 28.7%), which was significantly higher than the sites treated only with PRGF (30.0% ± 13.2%). CONCLUSION: From a histologic point of view, the use of autologous graft with or without PRGF seems to be the best strategy for socket regeneration within a short period of time (2 to 4 months). However, the application of PRGF alone inside fresh sockets may interfere with normal bone healing compared with control sites healed spontaneously.


Asunto(s)
Materiales Biocompatibles , Alveolo Dental , Materiales Biocompatibles/uso terapéutico , Trasplante Óseo , Humanos , Boca , Extracción Dental , Alveolo Dental/patología , Alveolo Dental/cirugía
15.
Materials (Basel) ; 15(13)2022 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-35806567

RESUMEN

Aim: The aim of this study was to compare the cyclic fatigue strength of different reciprocating rotary systems depending on the movement used. Methods: Four study groups were analyzed (n = 30): (1) Reciproc®, (2) Reciproc Blue®, (3) Wave One Gold® and (4) Procodile®. Each group was divided into three subgroups according to the motion used: (A) Reflex Dynamic® (n = 10), (B) ReFlex Smart® (n = 10) and (C) conventional reciprocating motion (n = 10). They were used in a dynamic cyclic fatigue prototype until their fracture, and the time was measured in seconds. The results obtained were analyzed with the ANOVA method, and for two-to-two comparisons, the Tukey method and Weibull statistics were used. Results: Procodile ReFlex Smart had the longest time to failure, and statistically significant differences were found between Procodile ReFlex Smart and the other files and motions (p < 0.05). Conclusion: Smart motions increase cyclic fatigue strength. ReFlex Smart® motion increases the cyclic fatigue strength of reciprocating rotary systems, and Procodile® ReFlex Smart was the most resistant system file.

16.
J Clin Exp Dent ; 14(3): e293-e297, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35317297

RESUMEN

Introduction: To describe a clinical case on cancer patient with ablative tumor surgery, from treatment planning, surgical resection and subsequent implantological rehabilitation. Case Report: A 61-year-old male, diagnosed with a squamous cell carcinoma in the maxilla, requires the removal of the lesion and corresponding oral rehabilitation. However, two surgeries were necessary to rehabilitate the upper jaw. A custom-made prosthesis was fabricated. It was made from sintered titanium using machined subperiosteal implants with a universal external connection. Finally, a milled cobalt- chrome structure was produced and a feldspar ceramic covering was subsequently applied. Conclusions: Rehabilitation using subperiosteal implants may be an alternative tool for complex surgery involving large atrophies or cancer patients who have undergone highly ablative surgery. Key words:Oral rehabilitation, oral cancer, subperiostal implants.

17.
Front Bioeng Biotechnol ; 10: 986112, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36225604

RESUMEN

Titanium and alloy osseointegrated implants are used to replace missing teeth; however, some fail and are removed. Modifications of the implant surface with biologically active substances have been proposed. MEDLINE [via Pubmed], Embase and Web of Science were searched with the terms "titanium dental implants", "surface properties", "bioactive surface modifications", "biomolecules", "BMP", "antibacterial agent", "peptide", "collagen", "grown factor", "osseointegration", "bone apposition", "osteogenic", "osteogenesis", "new bone formation", "bone to implant contact", "bone regeneration" and "in vivo studies", until May 2022. A total of 10,697 references were iden-tified and 26 were included to analyze 1,109 implants, with follow-ups from 2 to 84 weeks. The ARRIVE guidelines and the SYRCLE tool were used to evaluate the methodology and scientific evidence. A meta-analysis was performed (RevMan 2020 software, Cochane Collaboration) with random effects that evaluated BIC at 4 weeks, with subgroups for the different coatings. The heterogeneity of the pooled studies was very high (95% CI, I2 = 99%). The subgroup of BMPs was the most favorable to coating. Surface modification of Ti implants by organic bioactive molecules seems to favor osseointegration in the early stages of healing, but long-term studies are necessary to corroborate the results of the experimental studies.

18.
J Clin Med ; 11(10)2022 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-35629044

RESUMEN

(1) Background: This study compared the clinical and esthetic results of the double lateral sliding bridge flap (DLSBF) and the laterally closed tunnel (LCT) techniques, with a subepithelial connective tissue graft (SCTG), for the treatment of single Miller class II-III recessions in the mandibular anterior teeth. (2) Methods: This pseudorandomized clinical trial evaluated 14 patients, 7 of whom were part of the DLSBF + SCTG group, with an average follow-up of 58.7 ± 24.0 months, and 7 of whom were in the LCT + SCTG group, with an average follow-up of 16.7 ± 3.3 months. Clinical and esthetic evaluations of the following parameters were performed and the results for the two groups were compared: gingival recession depth, probing depth, keratinized tissue width, gingival thickness, percentage of root coverage and root coverage esthetic score. (3) Results: After the follow-up period, each technique provided evidence of a reduction in recession depth and clinical attachment level, as well as increased keratinized tissue width and gingival thickness, with statistically significant differences (p < 0.05). The analysis showed that gingival recession depth decreased less in the DLSBF group (4.3 ± 1.2 mm to 0.6 ± 1.1 mm) than it did in the LCT group (4.9 ± 1.1 mm to 0.1 ± 0.4 mm), but no significant difference was found between the two groups. Similarly, a greater reduction in the clinical attachment level parameter was observed in the LCT group, while a greater increase in gingival thickness was observed in the DLSBF group. The presence of scars was the only parameter for which statistically significant differences (p < 0.05) between the two study groups were found. (4) Conclusions: Within the limitations of the study, it indicates that the LCT + SCTG technique may be considered an optimal technique in terms of reducing gingival recession depth, complete root coverage and esthetic results for the treatment of single gingival recessions in the mandibular anterior teeth.

19.
Materials (Basel) ; 14(10)2021 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-34066290

RESUMEN

Clinicians should be aware of the main methods and materials to face the challenge of bone shortage by manufacturing customized grafts, in order to repair defects. This study aims to carry out a bibliographic review of the existing methods to manufacture customized bone scaffolds through 3D technology and to identify their current situation based on the published papers. A literature search was carried out using "3D scaffold", "bone regeneration", "robocasting" and "3D printing" as descriptors. This search strategy was performed on PubMed (MEDLINE), Scopus and Cochrane Library, but also by hand search in relevant journals and throughout the selected papers. All the papers focusing on techniques for manufacturing customized bone scaffolds were reviewed. The 62 articles identified described 14 techniques (4 subtraction + 10 addition techniques). Scaffold fabrication techniques can be also be classified according to the time at which they are developed, into Conventional techniques and Solid Freeform Fabrication techniques. The conventional techniques are unable to control the architecture of the pore and the pore interconnection. However, current Solid Freeform Fabrication techniques allow individualizing and generating complex geometries of porosity. To conclude, currently SLA (Stereolithography), Robocasting and FDM (Fused deposition modeling) are promising options in customized bone regeneration.

20.
J Clin Med ; 10(19)2021 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-34640607

RESUMEN

This study aims to assess the treatment outcomes (functional and subjective) of full-arch fixed hybrid rehabilitations made of PEEK (poly-ether-ether-ketone) with milled crowns of nano-filled composite (NFC) supported on four to six implants. In this randomized clinical trial, 34 edentate patients in the upper and/or the lower jaws were treated with the fixed hybrid dentures. In 16 patients (47.1% of the sample), the implants were loaded immediately (IL) by means of a provisional fixed rehabilitation made of PMMA (polymethylmethacrylate) screwed on Multi-Unit (MU) abutments connected after emplacement of the implant; however, in the counterparts (n = 18) these MU abutments were covered by healing caps and were left unloaded during two months (conventional loading protocol-CL), when all patients received a fixed hybrid PEEK-NFC rehabilitation on the upper and/or the lower jaw. Treatment outcomes were assessed 12 months after prostheses delivery. Functional outcomes were calculated according to masticatory performance, estimated by mixing ability tests of two colored chewing gums after ten chewing strokes, by the occlusal force/area recorded by pressure-sensitive sheets, and by electromyography of masseters and temporal muscles at maximum biteforce. The subjective outcomes of the treatment were assessed using both the oral satisfaction scale (visual analog scale) and the Spanish version of the Oral Health Impact Profile (OHIP-20). The findings of the present study showed that treatment with fixed PEEK-NFC hybrid prostheses significantly improved the masticatory performance, bite force, occlusal pattern, quality of life, and satisfaction, with the IL group being those with significantly higher occlusal bite forces and greater satisfaction in comparison with CL group. It should be concluded that PEEK-NFC hybrid prostheses can improve several patient-centered outcomes and that loading protocol significantly affects the patient's self-rated satisfaction.

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