OBJECTIVES:The purpose of this study was to demonstrate the efficacy of Silver Diamine Fluoride (SDF) antibacterial solution in penetrating the demineralized areas of enamel.MATERIALS AND METHODS:It was considered a group of four extracted teeth (with no color fading, fissures, decay, or demineralization). Each tooth was sectioned in two equal parts, in mesio-distal direction, using a dental handpiece and a special rounded, flat bur. Each specimen was demineralized, for one minute, with 45% orthophosphoric acid, on occlusal and proximal zones. The specimens were then washed and dried with water-air dental syringe. All the probes were inspected with an optical microscope and enamel thickness was digitally measured. Advantage Arrest (Elevate Oral Care, USA), which contains SDF, was applied on the previous demineralized zones. The penetration of the substance was visually inspected with the optical microscope and electronically measured.RESULTS:It was observed an improvement in remineralizing the white spots on enamel surfaces, the optical microscope being able to detect both demineralization and the penetration of SDF through enamel.CONCLUSIONS:Based on our in vitro study, SDF (Advantage Arrest) was capable to induce/increase enamel remineralization, through SDF penetration.
The aim of the study was to determine the marginal and internal adaptation after curing of different composite resin restorations, using a nondestructive X-ray micro-computed tomography (micro-CT). Forty previously extracted human molars, kept in 10% formalin to preserve the bonding capabilities of the tooth structures, were divided into four groups based on the composite system used and different light-curing times. Class II (vertical slot) cavities were prepared on one proximal side and restored with dental composite using a Tofflemire matrix, with a bulk-fill composite resin (Venus Bulk Fill, Heraeus Kulzer) and a universal posterior composite (G-ænial Posterior, GC). A curing lamp (Kerr Demi Ultra) was used with different curing times. Micro-CT scanning was performed by using Nikon XTH 225ST to reveal any defects in adaptation or gaps at the tooth restoration interface. The 3D images of the adaptation around the restorations were reconstructed using VG Studio Max 2.2 and myVGL 2.2.6 64-bit software. All samples from the G-ænial group showed marginal and internal gaps, with G-ænial Posterior having higher polymerization shrinkage and marginal gap values. In the Venus Bulk Fill group, there were fewer restorations with internal and external gap formation. Micro-CT is a three-dimensional imaging technique that can nondestructively detect adaptation around the resin composite restorations at every level of the sample.
Implants have been around for many years already, having a lot of advantages and high success rates, by some authors even higher than 90%. Nevertheless, throughout the years, problems and failures have occurred in practice which led to bone loss around the implants and even, in some cases, to losing the implant itself. The phenomenon behind this pathological process -peri-implantitis - is believed to be the microleakage which occurs at the implant-abutment interface.This happens due to the existence of a gap present between the implant and the prosthetic abutment. Moreover, the microleakage is amplified because of the, so called, pumo effect. The pump effect occurs when the crown-abutment complex is subjected to occlusal, vertical and oblique, forces. During these micro-movements of the abutment, the microleakage intensifies and the bacteria can easily enter inside the implant, where is impossible to reach and remove through oral hygiene, thus, creating the perfect conditions for peri-implantitis. There are two major types of implant-abutment connections widely used nowadays -internal hex and conical -which are believed to influence the phenomenon and, so, the outcome. In the present study, both types of connections are tested, using Streptococcus Mutans, a common bacteria found in the oral cavity.
Critically ill polytrauma patients have increased production of free radicals (FRs) and consequent alterations in biochemical pathways, as well as disruption of cellular integrity, due to increased lipid peroxidation. The aim of this study was to investigate several biomarkers associated with increased oxidative stress in critically ill polytrauma patients, and to evaluate the effect of antioxidant treatment on the clinical outcome in these patients. A total of 67 polytrauma patients from an intensive care unit met the selection criteria. Antiox group included 35/67 patients who received antioxidant therapy, while 32/67 patients without antioxidant treatment were considered as control group. Antioxidant therapy consisted of simultaneous administration of Vitamin C (sodium ascorbate) and N-acetylcysteine, through continuous intravenous infusion. Clinical and paraclinical evaluation of the patients was performed daily until discharge or death. At admission, laboratory parameters did not differ significantly between two groups. At discharge/upon death, statistically significant differences in favor of Antiox group were observed in the following parameters: thrombocytes, activated partial thromboplastin time, prothrombin time, total bilirubin, total cholesterol, high-density lipoproteins, low-density lipoproteins, erythrocyte sedimentation rate, interleukin 6 (all p = 0.0001), total protein (p = 0.0005), serum albumin (p = 0.0004), lactate dehydrogenase (p = 0.0006), and C-reactive protein (p = 0.0014). Starting from day 5, the APACHE II score was significantly decreased in Antiox versus control group (p < 0.05). Finally, the sepsis incidence and mortality rate were significantly lower in Antiox group (p < 0.05). Decreasing the level of oxidative stress by antioxidant substances significantly correlated with a better prognosis and outcome in our patients. Further studies should elucidate more clearly the mechanism of action of antioxidants in critically ill polytrauma patients.
The aim of the study was to evaluate and to compare the interface and marginal leakage of dental composite resins using confocal laser scanning biological microscopy (CM). Ten class II cavities were prepared on the proximal surfaces of 10 extracted teeth, previously kept in 10% formalin to preserve the bonding properties of the tooth structures. Cavities were restored with dental composite resin using the 'open sandwich' technique and then assessed using CM Open marginal adaptations at the interfaces inside the composite resins were identified. The results obtained with CM helped to eliminate and reduce the background information collected from a distance from the focal plane and allowed for the acquisition of serial optical sections from thick tooth specimens. In vitro assessments were thus made using CM on the teeth structure, regarding the occurrence of potential micro-leakages at the restoration interface.
Technological improvements and the progress of new adhesive materials have led to the development of minimally invasive restorations, like overlays; these are also indicated in the treatment of pathological tooth wear caused by bruxism. In this study we evaluated the marginal adaptation of Tizian overlays through two non-invasive methods: digital microscopy and confocal laser scanning microscopy. 12 maxillary first premolars were extracted and prepared for overlays. The Tizian overlays were cemented with Variolonk II (Ivoclar Vivadent). The marginal adaptation of each specimen was analyzed, on all four surfaces, with a digital microscope at 40x to 800x magnification ratio; we also used a confocal laser scanning microscope, at 10x magnification, in Z mode, with 10 mu m slices and a resolution of 1020 x 1024. The exposure time per pixel was 8 mu s and the wavelength of the laser was set at 405 nm, corresponding to a blue light laser. We concluded that confocal laser scanning microscopy, with its a higher horizontal and vertical resolution with regard to digital microscopy, and with its volumetric reconstructions capability of the sample image, is therefore a more appropriate method for this particular dental field, i.e., to investigate the marginal adaptation of Tizian overlays.
The aim of this study was to evaluate a relatively new calcium silicate cement (Biodentine (R)) used as a dentine substitute. The marginal adaptation in Class II restorations have been studied; this is the spot, where gingival margins are situated apical to the cemento-enamel junction (CEJ). 20 Class II cavities have been prepared on mesial and distal surfaces of 10 extracted teeth, with margins extending 1 mm below the cementum-enamel junction. Cavities have been restored with composite resin and Biodentine (R) in an "open sandwich" technique. The assessment of the marginal adaptation was performed using Laser Scanning Confocal Microscopy. The considered interfaces have been evaluated and the differences between the different materials have been discussed. In conclusion, contemporary calcium silicate materials, such as Biodentine, can be used as substitute materials for the dentin. However, because Biodentine needs extensive time to set, the operating time is longer than when a Resin-Modified Glass-Ionomer (RMGI) is used.
Implants and biomaterials used in hard and soft oral tissue augmentation are very complex, but predictable to use nowadays, as the technological advances haven't skipped this field of medicine. Cases that were impossible to treat with implant retained fixed prosthesis some years ago, have become the daily practice of oral surgeons and dentists around the world. The new user-friendly products, together with simplified protocols, increased the practitioners' predictability and success rate, thus the biomaterial industry took a huge leap forward. As the biomaterial industry keeps developing continuously, making better and safer products, the surgical and prosthetic protocols evolve and change as well. On this matter, the implant placement has become safer, using digital surgical guides. Guided implant placement doesn't just allow the practitioner place the implant in the patient's bone, but, moreover, it helps him place it in the correct, 3D, prosthetic position. And, thus, guiding the future bone augmentation and regeneration as well, accordingly. So, the implant placement has shifted from bone-orientated to prosthetic-orientated, offering at the same time a better primary stability for the implants, due to the prior planning. The present clinical study aims to analyze the outcome of the digital guided protocol. Unlike the free-handed surgery, the digital guided surgery allows dentists and oral surgeons to place implants according to the future prosthetic position of the crowns, even in conditions of alveolar ridges with bone resorption. Moreover, it makes possible the "one day implant" concept, the dental technician being able to create the provisional crown/s in advance, knowing precisely the future position of the implant placement. So, at the time of the surgery, the provisional crown is also put in place, guiding the soft and hard tissue healing and also giving the patient a greater satisfaction.
Prevention and allopathic medicine gained attention, since it is possible for dentists to prevent demineralization, using plants and natural substances with well-known efficacy. The purpose of this study was to present new methods for teeth remineralization. It was made a selection of 10 extracted teeth, maintained in physiological serum, with no color fading, decay or demineralization. It was induced demineralization, with ortho-phosphoric acid (concentration 45 %), for one minute. The probes were visually and with optical coherence tomography (OCT) inspected. The natural product and the bonding with additional nanoparticles of argent were created and applied on the demineralization zone of the both groups of teeth. Each tooth in the first group had one plain surface demineralized. The second group of teeth had a cavity prepared on one of each tooth’s side. The pastes were applied on the demineralized surfaces and in the demineralized cavities for two minutes. After time expired, the pasta applied on the first group of teeth was washed away; the bonding above the second group of teeth was light cured. The probes were again visually and with OCT inspected. It was observed an improvement in remineralizing the white marks on plain surfaces and in the created cavities, the OCT being able to detect different levels of remineralization. The efficacy of natural pasta depends on the time it is applied and the concentration of the different main substances. Also, the type of surface, plain or occlusal facets, may influence the substances’ penetration ability. The non-invasive specific feature of these products, low costs and safety are strong positive aspects of this method of remineralization. However, the natural process of remineralization is a long-lasting one; perfecting the main substances in order to accelerate the process, in addition to several in vivo studies would be necessary to be fulfilled.
Digital imprint and computer-aided design/computer-aided manufacture (CAD/CAM) systems offer several benefits compared to traditional techniques. The use of a CAD/CAM system to scan preparations and generate restorations in-office, removes a second appointment for the patient. The existence of precision benefits in using complete systems and chairside scanning systems, has been proven. CAD/CAM restorations have a good longevity and meet the accepted clinical parameters. New digital impression methods are presently accessible, and before long, the long-awaited goal of sparing patients of one the most unpleasant practices in clinical dentistry, acquiring dental impressions, will be exchanged by intraoral digital scanning. CAD/CAM systems existing nowadays, can feed data through accurate digital scans created from plaster models, straight to manufacturing systems that can shape ceramic or resin restorations with no requirement of a physical copy of the prepared, adjacent, and antagonist teeth.
One of the main causes of death in the world is lung cancer. According to the World Health Organization, the annual incidence of lung cancer increases significantly. Moreover, lung cancer accounts for one of the highest mortality rates, mainly due to late detection. Numerous studies have been conducted in order to identify new biomarkers for early diagnosis and for monitoring and evaluation of lung cancer stages. An ideal biomarker candidate is represented by the analysis of microRNAs expression. In this paper, we want to summarize microRNAs expressions in lung cancer. We also want to present the expression of microRNAs depending on the evolution of lung cancer. For this study, we analyzed the studies available in scientific databases, such as PubMed and Scopus. The studies were selected using the search keywords “microRNAs expression,” “lung cancer,” and “genetic biomarkers.” The most significant articles were selected for the study, following rigorous analysis. To evaluate and monitor lung cancer, the expression of microRNAs may be used successfully due to increased specificity and selectivity. However, further studies are needed on the assignment and validation of microRNAs for each type of lung cancer, respectively, for each stage of evolution.
Abstract The current practice in the field of forensic medicine imposes the use of modern investigation techniques. The complexity of laboratory investigation methods needed for a final result of the investigation in forensic medicine needed new biomarkers of higher specificity and selectivity. Such biomarkers are the microRNAs (miRNAs), short, non-coding RNAs composed of 19–24 nucleotides. Their characteristics, such as high stability, selectivity, and specificity for biological fluids, differ from tissue to tissue and for certain pathologies, turning them into the ideal candidate for laboratory techniques used in forensic medicine. In this paper, we wish to highlight the biochemical properties and the usefulness of miRNAs in forensic medicine.
The critically ill polytrauma patient presents with a series of associated pathophysiologies secondary to the traumatic injuries. The most important include systemic inflammatory response syndrome (SIRS), sepsis, oxidative stress (OS), metabolic disorders, and finally multiple organ dysfunction syndrome (MODS) and death. The poor outcome of these patients is related to the association of the aforementioned pathologies. The nutrition of the critically ill polytrauma patient is a distinct challenge because of the rapid changes in terms of energetic needs associated with hypermetabolism, sepsis, SIRS, and OS. Moreover, it has been proven that inadequate nutrition can prolong the time spent on a mechanical ventilator and the length of stay in an intensive care unit (ICU). A series of mathematical equations can predict the energy expenditure (EE), but they have disadvantages, such as the fact that they cannot predict the EE accurately in the case of patients with hypermetabolism. Indirect calorimetry (IC) is another method used for evaluating and monitoring the energy status of critically ill patients. In this update paper, we present a series of pathophysiological aspects associated with the metabolic disaster affecting the critically ill polytrauma patient. Furthermore, we present different non-invasive monitoring methods that could help the intensive care physician in the adequate management of this type of patient.
Introduction: Photoacoustic microscopy, also known as optoacoustic imaging, is a comparatively new method of investigation in dental medicine, which uses a laser-generated ultrasound (short laser pulses) to achieve images for interpretation. Photoacoustic microscopy can be used in a broad spectrum, from detecting tooth decay at its earliest stages to dental anatomy analysis. Material and methods: The energy emitted by the photoacoustic pulse is moderately absorbed by the target and exchanged into heat, leading to a local transitory temperature upsurge. The tension propagates and grows as ultrasonic waves, distinguished by the ultrasonic transducers which are planted apart from the tissue. The photoacoustic microscope has a tunable dye laser which passes through a condensing lens, an objective and ultimately an ultrasonic transducer attached to an acoustic lens to capture and receive information about the scanned probe from a sample moved on the X, Y dimensions. Results: The precise anatomy of layered concentric structures can be clearly observed in photoacoustic microscopy. The image value of the inner layer can be higher, indicating strong optical absorption, while the image value of the outer layer is lower, indicating weaker optical absorption. Meanwhile, the inner layer has the exact same size as the dentin structure and the outer layer has the exact same size as the enamel structure in this cross-section. Conclusions: The photoacoustic microscope (all-optical) comes out to be a future and promising tool for detecting early-stage caries and lesions on the surface of the teeth, where micro-leakage occurs at the interface of tooth restoration, and also the anatomy of dental tissues.
Three-dimensional (3D) printing is an additive manufacturing method in which a 3D item is formed by laying down successive layers of material. 3D printers are machines that produce representations of objects either planned with a CAD program or scanned with a 3D scanner. Printing is a method for replicating text and pictures, typically with ink on paper. We can print different dental pieces using different methods such as selective laser sintering (SLS), stereolithography, fused deposition modeling, and laminated object manufacturing. The materials are certified for printing individual impression trays, orthodontic models, gingiva mask, and different prosthetic objects. The material can reach a flexural strength of more than 80 MPa. 3D printing takes the effectiveness of digital projects to the production phase. Dental laboratories are able to produce crowns, bridges, stone models, and various orthodontic appliances by methods that combine oral scanning, 3D printing, and CAD/CAM design. Modern 3D printing has been used for the development of prototypes for several years, and it has begun to find its use in the world of manufacturing. Digital technology and 3D printing have significantly elevated the rate of success in dental implantology using custom surgical guides and improving the quality and accuracy of dental work.
AbstractIntroduction: Dental decays remain the most common and rampant biofilm-dependent oral disorders. Influencing the delicate dynamic between demineralization and remineralization is a big challenge in clinical practice, and nanotechnology is considered a viable solution. The therapeutic management of caries, which includes nanotechnology, has two big approaches, an antibacterial one and a remineralizing one. Silver is recognized to display a powerful toxicity to a large variety of micro-organisms, thus silver-based composites have been widely used in several bactericidal applications.Case report: We present our attempts and results in using silver nanoparticle solutions on a 14-year-old and a 34-year-old patient with dental decays and no previous dental pain. One of the cases was treated with chlorhexidine 2% and the other with Nanocare Plus, as antimicrobial agents. In both cases we recorded decreased values of the bacterial burden in comparison with the initial values.Conclusion: This two-case presentation compared the antibacterial effect of two antibacterial solutions, providing useful information regarding novel therapies for dental caries, but further research in this domain is needed.
In clinical dental practice it is often difficult or even impossible to distinguish and control interfacial adhesive defects from adhesive restorations using visual inspection or other traditional diagnostic methods. Nonetheless, non-invasive biomedical imaging methods like Optical Coherence Tomography (OCT) may provide a better view in this diagnostic outline. The aim of this study is to explore evaluations of the marginal adaptation of class I resin composites restorations using Time Domain (TD) OCT. Posterior human teeth have been chosen for this study. The teeth were stored in 0.9% physiological saline solution prior to use. A classical round-shaped class I cavity was prepared and cavities were restored with Charisma Diamond composite by Heraeus Kulzer and using a system of etch and rinse boding. The specimens were subjected to water storage and then to thermo-cycling. Three dimensional (3-D) scans of the restoration were obtained using a TD-OCT system centered at a 1300 nm wavelength. Open marginal adaptation at the interfaces and gaps inside the composite resins materials were identified using the proposed method. In conclusion, OCT has numerous advantages which justify its use for in vitro, as well as for in vivo studies. It can therefore be considered for non-invasive and fast detection of gaps at the restoration interface.
Cardiovascular disease is a leading cause of death globally. At present, there are many ways to diagnose this pathophysiology. The greatest disadvantages related to current biomarkers are their low specificity, low selectivity and low accuracy. A new method, extensively studied recently, is the expression of miRNAs, used as genetic biomarkers for the early diagnosis of cardiovascular diseases. This paper presents an update of miRNAs species expression that can serve as early diagnostic biomarkers and for the continuous monitoring of patients with cardiovascular disease.
Alginate impression is an elastic material included in the category of irreversible hydrocolloids. Obtaining indirect restorations cannot be separated from this material that has withstood the test of time (even if other elastic materials appeared more accurate). It is one of the most commonly used material impression and the price / quality ratio is favourable. Their chemical composition, setting time, dimensional stability and change have been the subject of exhaustive studies since their patenting in 1940. The aim of the study was to measure the dimensional change and mass loss of alginate impression. The material used was commercially XantALGIN Select Fast Set from Heraeus Kulzer's company. It was mixed according to the manufacturer. There were made 20 impressions on mandibular study models made of epoxy resin. After the preparation, these impressions were weighed and measured for 6 hours. For measuring dimensional changes there were used Stainless Hardened calliper and height measurements consisted of measuring the lateral incisor, the first premolar and the second molar, mesial - distal width and sagittal plane of the teeth (vestibular - oral). The dimensional variation used a CAD Scanner DD Argus M1 and a 3D Designer program by Exocad to process the information. For the mass of the impression, there was a slight initial decrease at first, followed by a bigger decrease of its mass at the end of the time for evaluation. The trend observed was the change in size - it was an initial expansion, followed by a regress, then another expansion (in the first hour), finally observing a decrease in the net, in the last 5 hours of the measuring. This study revealed that the mass and dimensional variations were not stable. Therefore, the best period of time to make the impression is the first half hour.