The Benefits of Smart Nanoparticles in Dental Applications.

Dentistry, as a branch of medicine, has undergone continuous evolution over time. The scientific world has focused its attention on the development of new methods and materials with improved properties that meet the needs of patients. For this purpose, the replacement of so-called "passive" dental materials that do not interact with the oral environment with "smart/intelligent" materials that have the capability to change their shape, color, or size in response to an externally stimulus, such as the temperature, pH, light, moisture, stress, electric or magnetic fields, and chemical compounds, has received much attention in recent years. A strong trend in dental applications is to apply nanotechnology and smart nanomaterials such as nanoclays, nanofibers, nanocomposites, nanobubbles, nanocapsules, solid-lipid nanoparticles, nanospheres, metallic nanoparticles, nanotubes, and nanocrystals. Among the nanomaterials, the smart nanoparticles present several advantages compared to other materials, creating the possibility to use them in various dental applications, including preventive dentistry, endodontics, restoration, and periodontal diseases. This review is focused on the recent developments and dental applications (drug delivery systems and restoration materials) of smart nanoparticles.

Surface Activation of Titanium Dental Implants by Using UVC-LED Irradiation.

Organic contaminants significantly limit the bioactivity of titanium implants, resulting in the degradation known as the ageing of titanium. To reactivate the surfaces, they can be photofunctionalized, i.e., irradiated with C-range ultraviolet (UVC) light. This descriptive in vitro study compares the effectiveness of novel light-emitting diode (LED) technology to remove contaminant hydrocarbons from three different commercially available titanium dental implants: THD, TiUnite, and SLA. The surface topography and morphology were characterized by scanning electron microscopy (SEM). The chemical compositions were analyzed by X-ray photoelectron spectroscopy (XPS), before and after the lighting treatment, by a pair of closely placed UVC (λ = 278 nm) and LED devices for 24 h. SEM analysis showed morphological differences at the macro- and micro-scopic level. XPS analysis showed a remarkable reduction in the carbon contents after the UVC treatment: from 25.6 to 19.5 C at. % (carbon atomic concentration) in the THD; from 30.2 to 20.2 C at. % in the TiUnite; from 26.1 to 19.2 C at. % in the SLA surface. Simultaneously, the concentration of oxygen and titanium increased. Therefore, LED-based UVC irradiation decontaminated titanium surfaces and improved the chemical features of them, regardless of the kind of surface.

Implant-supported fixed hybrid acrylic complete dentures opposing fully restored mandibular metal ceramic restorations.

This report presents a full-mouth rehabilitation case. A patient came with a failing dentition in maxilla, and after the treatment, the patient had a shortened full-arch, implant-supported, screw-retained hybrid acrylic complete denture in the maxilla and full-arch metal ceramic restorations in the mandible. The report describes the steps involved in the prosthodontic rehabilitation; a cost-effective treatment plan, the restoration of vertical dimension, an immediate denture, an implant-level impression, a verified-master cast, the fabrication of definitive prosthesis, the occlusal scheme and multiple follow-ups in 6 months. We discussed the merits/demerits of screw-retained prosthesis, impression techniques and various types of fixed complete dentures. We learnt the difficulty in hygiene measures and dissatisfaction of the patient with the hygienic gaps under the acrylic fixed dentures.

Technical note on introducing a digital workflow for newborns with craniofacial anomalies based on intraoral scans - part I: 3D printed and milled palatal stimulation plate for trisomy 21.

BACKGROUND: Advanced digital workflows in orthodontics and dentistry often require a combination of different software solutions to create patient appliances, which may be a complex and time-consuming process. The main objective of this technical note is to discuss treatment of craniofacial anomalies using digital technologies. We present a fully digital, linear workflow for manufacturing palatal plates for infants with craniofacial anomalies based on intraoral scanning. Switching to intraoral scanning in infant care is advantageous as taking conventional impressions carries the risk of impression material aspiration and/or infections caused by material remaining in the oronasal cavity. MATERIAL AND METHODS: The fully digital linear workflow presented in this technical note can be used to design and manufacture palatal plates for cleft palate patients as well as infants with functional disorders. We describe the workflow implemented in an infant with trisomy 21. The maxilla was registered using a digital scanner and a stimulation plate was created using dental CAD software and an individual impression tray module on a virtual model. Plates were manufactured using both additive and subtractive methods. Methacrylate based light curing resin and Poly-Ether-Ether-Ketone were the materials used. RESULTS: The palatal area was successfully scanned to create a virtual model. The plates fitted well onto the palatal area. Manual post-processing was necessary to optimize a functional ridge along the vestibular fold and remove support structures from the additively manufactured plate as well as the milled plate produced from a blank. The additively manufactured plate fitted better than the milled one. CONCLUSION: Implementing a fully digital linear workflow into clinical routine for treatment of neonates and infants with craniofacial disorders is feasible. The software solution presented here is suitable for this purpose and does not require additional software for the design. This is the key advantage of this workflow, which makes digital treatment accessible to all clinicians who want to deal with digital technology. Whether additive or subtractive manufacturing is preferred depends on the appliance material of choice and influences the fit of the appliance.

Pressure Cycling Technology Assisted Mass Spectrometric Quantification of Gingival Tissue Reveals Proteome Dynamics during the Initiation and Progression of Inflammatory Periodontal Disease.

Understanding the progression of periodontal tissue destruction is at the forefront of periodontal research. The authors aimed to capture the dynamics of gingival tissue proteome during the initiation and progression of experimental (ligature-induced) periodontitis in mice. Pressure cycling technology (PCT), a recently developed platform that uses ultra-high pressure to disrupt tissues, is utilized to achieve efficient and reproducible protein extraction from ultra-small amounts of gingival tissues in combination with liquid chromatography-tandem mass spectrometry (MS). The MS data are processed using Progenesis QI and the regulated proteins are subjected to METACORE, STRING, and WebGestalt for functional enrichment analysis. A total of 1614 proteins with ≥2 peptides are quantified with an estimated protein false discovery rate of 0.06%. Unsupervised clustering analysis shows that the gingival tissue protein abundance is mainly dependent on the periodontitis progression stage. Gene ontology enrichment analysis reveals an overrepresentation in innate immune regulation (e.g., neutrophil-mediated immunity and antimicrobial peptides), signal transduction (e.g., integrin signaling), and homeostasis processes (e.g., platelet activation and aggregation). In conclusion, a PCT-assisted label-free quantitative proteomics workflow that allowed cataloging the deepest gingival tissue proteome on a rapid timescale and provided novel mechanistic insights into host perturbation during periodontitis progression is applied.

Accuracy of Dental Monitoring 3D digital dental models using photograph and video mode.

INTRODUCTION: This study aimed to test the accuracy of the 3-dimensional (3D) digital dental models generated by the Dental Monitoring (DM) smartphone application in both photograph and video modes over successive DM examinations in comparison with 3D digital dental models generated by the iTero Element intraoral scanner. METHODS: Ten typodonts with setups of class I malocclusion and comparable severity of anterior crowding were used in the study. iTero Element scans along with DM examination in photograph and video modes were performed before tooth movement and after each set of 10 Invisalign aligners for each typodont. Stereolithography (STL) files generated from the DM examinations in photograph and video modes were superimposed with the STL files from the iTero scans using GOM Inspect software to determine the accuracy of both photograph and video modes of DM technology. RESULTS: No clinically significant differences, according to the American Board of Orthodontics-determined standards, were found. Mean global deviations for the maxillary arch ranged from 0.00149 to 0.02756 mm in photograph mode and from 0.0148 to 0.0256 mm in video mode. Mean global deviations for the mandibular arch ranged from 0.0164 to 0.0275 mm in photograph mode and from 0.0150 to 0.0264 mm in video mode. Statistically significant differences were found between the 3D models generated by the iTero and the DM application in photograph and video modes over successive DM examinations. CONCLUSIONS: 3D digital dental models generated by the DM smartphone application in photograph and video modes are accurate enough to be used for clinical applications.

Escaneamento digital e prototipagem 3d para confecção de laminados cerâmicos: relato de caso clínico / Digital Scanning and 3D Prototyping for Ceramic Laminate Confection: Clinical Case

Introdução:lentes de contato dentais podem ser uma excelente opção para correção de cor, forma, tamanho e posicionamento dental. Entretanto é umtratamentoque requer várias etapas laboratoriais com riscos de distorções nas etapas de moldagem e vazamento do modelo. Desta forma, desadaptações dos laminados em boca podem ser frequentes.Objetivo:relatar um caso clínico de nove laminados cerâmicos em que foi empregado o escaneamento digital, troquelização virtual e prototipagem do modelo em 3D.Método:paciente do gênero feminino, 59 anos, buscou atendimento odontológico queixando-se de desproporcionalidade dentária ao sorrir. Ao exame clínico foi observada uma inclinação maxilar que causava aquela desarmonia. Foi proposta a confecção de laminados cerâmicos para compensar a discrepância óssea bem como melhorar forma, contorno e cromia dentária. Após planejamento digital, confecção do enceramento diagnóstico, mock up, e aceita do planejamento por parte da paciente, iniciaram-se os preparos dentários. Finalizada esta etapa, os dentes foram escaneados (Trios 3Shape), troquelizados e prototipados em impressora 3D. O modelo foi encaminhado ao laboratório que confeccionou as peças protéticas em dissilicato de lítio de forma injetada e maquiada. Por fim, foram realizadas as provas secas, úmidas, ajustes necessários e cimentação dos laminados com cimento resinoso fotopolimerizável.Conclusão:a tecnologia empregada se mostrou eficiente na resolução do caso, sendo uma técnica rápida, que causou pouco desconforto à paciente e oportunizou uma boa adaptação dos laminados cerâmicos (AU).

Introduction:laminates veneers can be an excellent choice for color correction, shape, size and dental positioning. However, it is a technique that requires several laboratory steps with risks of distortion in the molding and casting steps of the model. Thus, maladjustments of laminatesin the mouth may be frequent.Objective:to report a clinical case of nine ceramic laminates through the digital scanning, virtual punching and 3D prototyping of the model.Methods:A 59 years old woman showed up to dental clinic searched dental care complaining of dental disproportionality when smiling. At the clinical examination, a maxillary inclination was observed that caused disharmony. It was proposed the making of ceramic laminates to compensate the bone discrepancy as well as improve shape, contour and dental color. After the digital planning, preparation diagnostic wax-up, mock up, and acceptance of patient planning, the dental preparations were started. After this step, the teeth were scanned (Trios 3Shape), punched and prototyped in a 3D printer. The model was sent to the laboratory to do the prosthetic parts in lithium disilicate in an injected and makeup manner. At last, it were made the tests dry, wet, required adjustments finally cementation of the ceramic laminates with photopolymerizable resin cement. Conclusions:the technology employed was efficient in solving this case, being a fast technique, which caused little discomfort to the patient and provided a good adaptation of the ceramic laminates (AU).

Oral Implantology: Myths Exposed in Recent Research.

Today, a variety of surgical and prosthetic protocols, implant designs, and prosthetic devices are used for implant dentistry, employing many different dental technologies. With a plethora of options available, choosing an implant system has become highly challenging for practitioners. Having an understanding of the role of different implant design properties may help clinicians make informed decisions. This article provides an overview of factors affecting osseointegration and preservation of bone and discusses the importance of surgical and prosthetic treatments that respect the biologic width and avoid interventions, such as cementation, that may disturb the surrounding soft and hard tissues.

Optical Coherence Tomography.

Optical coherence tomography (OCT) is a noninvasive diagnostic technique providing cross-sectional images of biologic structures based on the differences in tissue optical properties. OCT has been widely used in numerous clinical applications and is becoming popular as a promising technology in dentistry. Today, dental hard (tooth) and soft (hard palate mucosa and gingiva mucosa) tissues are visualized with OCT. With new developments in technology, the applications of OCT are being investigated in various fields in dentistry, such as to detect microleakage around restoration, tooth cracks/fractures, examination of periodontal tissues/pockets, early detection of oral cancerous tissues, and in endodontics for location of pulp canal.

Fluorescence and Near-Infrared Light Transillumination.

This article describes the current applications of various technologies based on either autofluorescence or near-infrared light illumination, tailored to aid practitioners in detecting and quantitatively monitoring oral diseases such as dental caries and oral cancer at the earliest stage of their formation, or in the conservative surgical excision of necrotic bones in diseases such as chronic osteomyelitis, osteoradionecrosis, and medication-related osteonecrosis of the jaw. The data discussed are primarily based on published scientific studies and reviews from case reports, clinical trials, and in vitro and in vivo studies. References have been traced manually, by MEDLINE, or through manufacturer's websites.

MRI for Dental Applications.

Imaging of hard and soft tissue of the oral cavity is important for dentistry. However, medical computed tomography, cone beam computed tomography (CBCT), nor MRI enables soft and hard tissue imaging simultaneously. Some MRI sequences were shown to provide fast soft and hard tissue imaging of hydrogen, which increased the interest in dental MRI. Recently, MRI allowed direct visualization of cancellous bone, intraoral mucosa, and dental pulp despite that cortical bone and dental roots are indirectly visualized. MRI seems to be adequate for many indications that CBCT is currently used for: implant treatment and inflammatory diseases of the tooth.

Comparison of Resonance Frequency Analysis and of Quantitative Ultrasound to Assess Dental Implant Osseointegration.

Dental implants are widely used in the clinic. However, there remain risks of failure, which depend on the implant stability. The aim of this paper is to compare two methods based on resonance frequency analysis (RFA) and on quantitative ultrasound (QUS) and that aim at assessing implant stability. Eighty-one identical dental implants were inserted in the iliac crests of 11 sheep. The QUS and RFA measurements were realized after different healing times (0, 5, 7, and 15 weeks). The results obtained with the QUS (respectively RFA) method were significantly different when comparing two consecutive healing time for 97% (respectively, 18%) of the implants. The error made on the estimation of the healing time when analyzing the results obtained with the QUS technique was around 10 times lower than that made when using the RFA technique. The results corresponding to the dependence of the ISQ versus healing time were significantly different when comparing two directions of RFA measurement. The results show that the QUS method allows a more accurate determination of the evolution of dental implant stability when compared to the RFA method. This study paves the way towards the development of a medical device, thus providing a decision support system to dental surgeons.

Evaluation of dental implant stability in bone phantoms: Comparison between a quantitative ultrasound technique and resonance frequency analysis.

BACKGROUND: Resonance frequency analyses and quantitative ultrasound methods have been suggested to assess dental implant primary stability. PURPOSE: The purpose of this study was to compare the results obtained using these two techniques applied to the same dental implants inserted in various bone phantoms. MATERIALS AND METHODS: Different values of trabecular bone density and cortical thickness were considered to assess the effect of bone quality on the respective indicators (UI and ISQ). The effect of the implant insertion depth and of the final drill diameter was also investigated. RESULTS: ISQ values increase and UI values decrease as a function of trabecular density, cortical thickness and the screwing of the implant. When the implant diameter varies, the UI values are significantly different for all final drill diameters (except for two), while the ISQ values are similar for all final drill diameters lower than 3.2 mm and higher than 3.3 mm. The error on the estimation of parameters with the QUS device is between 4 and 8 times lower compared to that made with the RFA technique. CONCLUSIONS: The results show that ultrasound technique provides a better estimation of different parameters related to the implant stability compared to the RFA technique.

PECULIARITIES OF THE OCCLUSION FORMATION IN DENTAL IMPLANT SUPPORTED ARTIFICIAL TEETH.

The aim of this study was to assess and develop an effective computer technology assisted method for improved treatment of dental implant patients. Both an experimental and clinical assessments were conducted. The experimental part was performed to develop the mathematical models for calculating and analyzing the tensely deformed condition (TDC) in the system "non-removable prosthesis - dental implant - lower jaw " (PIJ). Clinical study was conducted on 76 patients with previously placed dental implant supported prostheses in the posterior parts of the lower jaw (with and without signs of bone receding around the implants) allocated into three groups. Results of the study allowed the authors to suggest an effective computer technology supported method for assessing the required angles of dental implants, which provides an opportunity for individual calculation of the dental implant in the bone of the mandible depending on the direction of functional load.

NON-REMOVABLE DENTURE PROTOTYPES, EFFECTIVE IN DENTAL IMPLANTATION.

Temporary prosthesis transformed into a prosthetic prototypes and manufactured by CAD/CAM technologies (computer copy milling) are used to specify the final form of future permanent restoration and to correct occlusal relationships, vertical size of non-removable dentures, and their occlusal surfaces. A progressive loading on bone tissue in the implantation area and soft tissues formation, have been assessed. In this regard, the choice and placement of temporary mini-implants, as the supports for non-removable denture prototypes for the period of osseointegration of two-stage intraosseous dental implants, are the issues of great importance. Temporary dental implants are the object of complex loads of different magnitude, duration and direction. The action of the prosthesis is closely related to load delivery to the surface of dental implant between the components of the system - "implant-temporary prosthesis". According to the study results, minimization of the momentum acting on temporary implants in the mesiodistal direction allows reducing stress level in the areas of permanent implant placement.

Comparison of decalcifying agents and techniques for human dental tissues.

Teeth are among the hardest animal tissues, because they are composed of large amounts of inorganic compounds. Consequently, teeth are difficult to prepare for microscopic examination. Acids and chelating agents traditionally have been used to remove calcium ions. We compared decalcifying agents including strong acids, weak acids, chelating agents, techniques using electric current, agitation and heat. Freshly extracted teeth were fixed and decalcified using formic acid-formalin, formal-nitric acid, formalin-EDTA, Von Ebner's fluid and Perenyi's fluid. Three additional techniques including formic acid with agitation, formic acid with heat and formic acid with electric current also were evaluated. Decalcified teeth were evaluated histologically for tissue preservation and staining characteristics. Formic acid with gentle agitation produced the best decalcification overall based on time required for decalcification, ease of sectioning, hard and soft tissue staining and tissue preservation. Our findings support the use of agitation with formic acid decalcification, because it reduces significantly both the time required and the deleterious effects of prolonged immersion.

Aportes de la odontología legal en la identificación humana: revisión de la literatura / Contributions of forensic dentistry to human identification: a reeview of the literature

El presente trabajo trata acerca de aspectos inherentes a la odontología legal, a fin de difundir la importancia del perito odontólogo en la identificación humana mediante el análisis de estructuras anatómicas del sistema estomatognático. Los dientes –que presentan una elevada resistencia a los agentes externos– son empleados a veces por las víctimas como unarma de defensa ante sus atacantes, o por estos últimos para dominar a las primeras. Dado que los dientes alojan el ADN en su interior, las huellas de mordeduras representan evidencias físicas que pueden permitir identificar a los involucrados en un suceso delictivo. Se mencionan programas informáticos para facilitar la conformación de bases de datos de información odontológica, poniendo énfasis en el correcto registro yarchivo por parte del odontólogo en la práctica clínica para contribuir con el accionar de aquellos colegas que se desempeñan como auxiliares de la Justicia.

[Diagnossis and treatment of complicated anterior teeth esthetic defects by combination of whole-process digital esthetic rehabilitation with periodontic surgery].

OBJECTIVE: To explore a new method of whole-process digital esthetic prosthodontic rehabilitation combined with periodontic surgery for complicated anterior teeth esthetic defects accompanied by soft tissue morphology, to provide an alternative choice for solving this problem under the guidance of three-dimensional (3D) printing digital dental model and surgical guide, thus completing periodontic surgery and digital esthetic rehabilitation of anterior teeth. METHODS: In this study, 12 patients with complicated esthetic problems accompanied by soft tissue morphology in their anterior teeth were included. The dentition and facial images were obtained by intra-oral scanning and three-dimensional (3D) facial scanning and then calibrated. Two esthetic designs and prosthodontic outcome predictions were created by computer aided design /computer aided manufacturing (CAD/CAM) software combined with digital photography, including consideration of white esthetics and comprehensive consideration of pink-white esthetics. The predictive design of prostheses and the facial appearances of the two designs were evaluated by the patients. If the patients chose the design of comprehensive consideration of pink-white esthetics, they would choose whether they would receive periodontic surgery before esthetic rehabilitation. The dentition design cast of those who chose periodontic surgery would be 3D printed for the guide of periodontic surgery accordingly. RESULTS: In light of the two digital designs based on intra-oral scanning, facing scanning and digital photography, the satisfaction rate of the patients was significantly higher for the comprehensive consideration of pink-white esthetic design (P<0.05) and more patients tended to choose priodontic surgery before esthetic rehabilitation. The 3D printed digital dental model and surgical guide provided significant instructions for periodontic surgery, and achieved success transfer from digital design to clinical application. The prostheses were fabricated by CAD/CAM, thus realizing the whole-process digital esthetic rehabilitation. CONCLUSION: The new method for esthetic rehabilitation of complicated anterior teeth esthetic defects accompanied by soft tissue morphology, including patient-involved digital esthetic analysis, design, esthetic outcome prediction, 3D printing surgical guide for periodontic surgery and digital fabrication is a practical technology. This method is useful for improvement of clinical communication efficiency between doctor-patient, doctor-technician and doctors from different departments, and is conducive to multidisciplinary treatment of this complicated anterior teeth esthetic problem.

Factors Influencing the Dimensional Accuracy of 3D-Printed Full-Coverage Dental Restorations Using Stereolithography Technology.

PURPOSE: The aim of the present study was to evaluate the effect of the build angle and the support configuration (thick versus thin support) on the dimensional accuracy of 3D-printed full-coverage dental restorations. MATERIALS AND METHODS: A full-coverage dental crown was digitally designed and 3D-printed using stereolithography-additive manufacturing (SLA-AM) technology. Nine different angles were used during the build process: 90, 120, 135, 150, 180, 210, 225, 240, and 270 degrees. In each angle, the crown was printed using a thin and a thick support type, resulting in 18 specimens. The specimens were digitally scanned using a high resolution optical surface scanner (IScan D104i; Imetric 3D). The dimensional accuracy was evaluated by digital subtraction technique. The 3D digital files of the scanned printed crowns (test model), exported in standard tessellation language (STL) format, were superimposed with the STL file of the designed crown (reference model) using Geomagic Studio 2014 (3D Systems). RESULTS: The root mean square estimate value and color map results suggest that the build angle and support structure configuration have an influence on the dimensional accuracy of 3D-printed crown restorations. Among the tested angles, the 120-degree build angle showed a minimal deviation of 0.029 mm for thin support and 0.031 mm for thick support, indicating an accurate fit between the test and reference models. Furthermore, the deviation pattern observed in the color map was homogenously distributed and located further away from the critical marginal area. CONCLUSIONS: Within the limitations of this study, the selection of build angle should offer the crown the highest dimensional accuracy and self-supported geometry. This allows for the smallest necessary support surface area and decreases the time needed for finishing and polishing. These properties were mostly observed with a build angle of 120 degrees combined with a thin support type.