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This article is a literature review and case report on the use of 3D printed Snap-On Smile devices for short-term aesthetic rehabilitation. The study found that the Snap-On Smile offers up to five years of use and can be manufactured using advanced techniques such as 3D printing. The case study of a 59-year-old female demonstrated the efficacy of the device in providing immediate aesthetic enhancement. The article concludes that the Snap-On Smile is a significant advancement in aesthetic dentistry, but its limitations should be carefully considered in complex cases. [Extracted from the article]

Translucent monolithic zirconia is the newest option of zirconia-based ceramics, which aimed to substitute the opaque classic yttria-stabilized tetragonal zirconia polycrystal (Y-TZPs) in more demanding esthetic cases.

Objectives: The study aimed to compare the color of monolithic and layered zirconia crowns fabricated using different brands in the cervical, middle, and incisal areas. Materials and Methods: A total of 45 crowns were fabricated from three brands (Katana, Nacera, Cercon) using three methods (monolithic = ML (n=5), cut‐back + enamel = BL (n=5), cut‐back + dentin + enamel = TL (n=5)). CIE L*, a* b*, C*, h° color coordinates were recorded with a dental spectrophotometer in cervical, middle, and incisal areas. Color differences between manufacturing techniques, tooth areas, and brands were calculated using the CIEDE2000(1:1:1) formula, and the values were compared to the perceptibility (PT00) and acceptability thresholds (AT00). Comparisons between color coordinates were analyzed statistically (Kruskal‐Wallis and Mann‐Whitney U tests, p < 0.001). Results: Significant differences were found between CIE L*, a*, b*, C*, h° coordinates of the zirconia crowns (p < 0.001), generally. The lowest color differences were obtained between BL and TL crowns in cervical and middle areas. Color differences between cervical and middle areas were mostly below PT00. An acceptable color difference was found between Katana and Cercon crowns. Conclusions: The manufacturing technique and the brand influenced the color of zirconia crowns. Also, the color of the crowns varied from cervical to incisal. Clinical Significance: Reproducing the optical properties of teeth with ceramic crowns might be challenging, given the differences in the internal configuration of the enamel and dentine, as well as their complex behavior when interacting with light. When deciding whether to fabricate a monolithic crown in translucent zirconia or improve its appearance by layering with more translucent glass–ceramic, the clinicians and dental technicians must be aware of these procedures' effect on the final color of the restorations. [ABSTRACT FROM AUTHOR]

Given the recent advances in 3D printing, MRI or CT images can now be used to manufacture 3D anatomical models of patient specific tissues. 3D printing is a process by which digital models (CAD) are converted into physical models through a layer-by-layer manufacturing procedure. Patient-specific printed models for the anatomical regions requiring surgical repair can offer surgeons a better view on the defective tissue, thus supporting in several ways preparation of the surgical procedure. Accordingly, given the growing interest in 3D printing of anatomical models, the present literature review aims at evaluating their clinical impact and benefits in oral-maxillofacial surgery. [ABSTRACT FROM AUTHOR]

Purpose: 1. to assess the ability of four brands of translucent monolithic zirconia with different thicknesses to mask discolored substrates; 2. to assess the influence of glazing upon their color coordinates and masking properties. Methods: Sixty samples of shade A1 (0.8, 1.5, and 2.0 mm thickness) from: ZirCAD/MT, Katana/HT, Vita YZ/HT, Cercon/HT were fabricated and glazed using a standardized laboratory procedure. CIE L*a*b* parameters were recorded on composite substrates, (IPS Natural Die Material Kit) (ND1=reference; ND2, ND3, ND4, ND5=test backgrounds), before and after glazing. The color changes of zirconia samples induced by glazing were analyzed. Masking properties was calculated as the color difference between CIE L*a*b* parameters of the samples placed on reference and test substrates with CIEDE2000(1:1:1) formula. The effect of material, thickness, substrate, and glazing on the color of monolithic zirconia was analyzed with ANOVA test and the multiple comparisons were analyzed with Tukey HSD tests (a=0.05). Results: After glazing, lightness L* significantly increased, while chromatic coordinates a* and b* decreased (p<0.05). Significant differences in the masking properties of the four materials (p<0.001) were found, with IPS e.max ZirCAD/MT having the lowest masking effect (p<0.001). Thickness, substrate and glazing had a significant effect on the color masking properties of monolithic zirconia (p<0.001). Conclusions: Masking properties of translucent zirconia were significantly influenced by the materials, the thickness and the color of the substrate; moreover, glazing improved the masking ability for all zirconia samples. [ABSTRACT FROM AUTHOR]

The purpose of this mini-review was to describe the CAD/CAM systems, their principles and their equipment, to highlight the major historical milestones in the development stages of dedicated dental CAD/CAM systems, and to identify the advantages/ disadvantages of using optical impressions compared to conventional impressions. This technique provides benefits in both directions of the designing and manufacturing process of a prosthetic restoration, i.e. in clinical and technological sectors. The main clinical benefits are strength, aesthetics, comfort, while the technical ones assure an easier, faster and more accurate fabrication process. [ABSTRACT FROM AUTHOR]

The films and the developing solutions used with radiological films contain a number of harmful substances that are very toxic to the environment, as well as to the living organisms, particularly aquatic organisms. Therefore, this type of toxic waste requires simple, but adequate collection and treatment measures, in order to be transformed into environmentally friendly products. This paper reviews the existent knowledge and the methods for the management of this special waste in dentistry-related units of dental radiology in Cluj-Napoca and Cluj County. An analysis of the answers reveals that many dentists do not know enough or do not use appropriate methods in radiological waste management, which can result in environmental pollution. [ABSTRACT FROM AUTHOR]

The mechanical behavior of periodontal ligaments belongs nowadays to the field of biomechanics. In this study, we investigate the vibrations of periodontal ligaments (PDL) under load as, by identifying the parameters of the system, one can obtain a series of data reflecting coupling of the tooth with the alveolar region. We started from the hypothesis that a tooth fixed in the alveolus and periodontal tissue is equivalent to an oscillating system with several degrees of freedom. We investigated the periodontal support of the abutments on which a three-element FPD was manufactured using the ultrasonic Doppler method of measuring tooth movement, known as a new testing method providing quantitative and accurate results. [ABSTRACT FROM AUTHOR]

The present research aims at studying the dynamic behavior of the abutment teeth of a dental phantom supporting a fixed metal-polymeric and porcelain-fused-to-metal partial denture. Simulation of a clinical situation was created using a Frasaco typodont on which the 2 teeth were positioned first freely then fixed with a siliconic material, which resulted in different damping and elastic constants. In the in vitro created cases, a laser Doppler vibrometer (LDV) was used as a scientific instrument for non-contact vibration measurements of the surface of abutment teeth. The laser beam from LDV was directed to the surface of interest, and the vibration amplitude and frequency were extracted from the Doppler shift of the reflected laser beam frequency, due to the surface motion. The output of LDV was a continuous analogue voltage, directly proportional to the target velocity component along the direction of the laser beam. [ABSTRACT FROM AUTHOR]

The aim of the study was to assess the effect of staining and bleaching on CAD/CAM materials with high (HT) and low translucency (LT or T). Samples were stored in coffee and subsequently bleached. CIELAB parameters were recorded at baseline, after coffee immersion, after bleaching. Translucency parameter (TP), whiteness index (WID) and color changes were calculated (ΔE00). Influence of staining and bleaching was analyzed with repeated-measures ANOVA and color differences between materials were analyzed with one-way ANOVA (a=0.05). Staining and bleaching significantly affected CIELAB parameters and WID for all materials (p<0.001). TP was significantly influenced by staining and bleaching for Crios and Enamic (p<0.05). Mean color differences were significantly different between materials (p<0.001). The greatest color changes due to staining were observed for Lava Ultimate while the lowest for e.max CAD. Both coffee staining and bleaching induced greater color changes for HT materials of the same brand compared to LT. [ABSTRACT FROM AUTHOR]

Objectives: To assess the effect of material, thickness and glazing upon the color, translucency, and roughness of monolithic zirconia. Materials and methods: Sixty discs (0.8, 1.5, and 2 mm thickness) were fabricated from A1 translucent zirconia (IPS e.max ZirCAD/MT, Katana/HT, Vita YZ/HT, Cercon/HT) and glazed. Roughness (Ra) was assessed with a profilometer and color coordinates were measured with a spectrophotometer on a black, white, and tooth‐shaded background before and after glazing. Relative translucency parameter (RTP), color differences (CIEDE2000) and differences in translucencies between materials, before and after glazing were calculated. RTP, Ra, color differences were statistically analyzed using ANOVA. Any significant interaction between factors was further analyzed using Tukey's HSD. Results: RTP values were significantly different between materials (P < .001) and thicknesses (P < .001), with the interaction effect between material type and thickness, also significant (P < .001). However, glazing did not have a significant effect on RTP values (P = .782). Color differences resulted after glazing were significantly different between materials (P < .001), and thicknesses (P < .001) with the interaction effect also significant (P < .001). Glazing influenced roughness, Ra decreasing for all materials (P < .001). Conclusions: As a result of glazing, only color changes were statistically significant. Translucency varied among brands of precolored monolithic zirconia; the differences increased for greater thicknesses. Clinical significance: Glazing is an important step in the technological process of ceramic restorations; however, it can influence the final optical appearance of the restoration as color changes could be expected after the application of the glaze. [ABSTRACT FROM AUTHOR]

Aim. To evaluate the degree of knowledge, acceptance and usage of dental CAD-CAM systems among dental technicians based in Romania and to identify the factors which contribute/ inhibit the usage of this technology. Materials and methods. A web-based survey containing 16 questions was distributed by means of an online social platform to dental technians practising in Romania. The questionnaire contained three different sections, focusing on topics related to the level of usage and common practices on subtractive manufacturing, demographics and perception of impact. Descriptive statistical analysis was used to quantify and interpret the resulting data. Results and disscusion. A number of 84 complete responses was obtained. The majority of respondents affirmed that they have theoretical knowledge about this technology (97.7%); also, a high number of dental technicians (54.8%) reported that they currently use some form of CAD-CAM technology in their laboratories. Most of the surveyed technicians acquired their knowledge in this domain through self-documentation, mainly using CAD-CAM to manufacture fixed restorations (91.3%). The majority of dental technicians (87%) consider that introduction of subtractive manufacturing systems has had a beneficial impact on their profession. Conclusions. Currently, a fairly moderate number of dental technicians in Romania are using CAD/ CAM systems in their clinical practice, as the large initial investment required for their purchasing is the main barrier for further implementation of this technology. [ABSTRACT FROM AUTHOR]

The aim of the present study is to evaluate the behavior of artificial teeth which support a porcelain-fused-to-metal (PFM) prosthetic reconstruction to mimic in vitro the movements of natural teeth under different simulated implantation degrees. A Frasaco typodont was used to this purpose and two different degrees of implantation were simulated. Non-contact vibration measurements of the samples were made using a laser Doppler vibrometer (LDV), and a continuous analogue voltage output of the LDV data was included in the study. [ABSTRACT FROM AUTHOR]

Introduction. The objective of this in-vitro study was to compare the accuracy, defined as trueness and precision, of an intraoral scanner and a cast scanner belonging to the same manufacturer (Dental Wings, Montreal, Canada). Materials and methods. An experimental model consisting of a die with a standard preparation for a porcelain fused to a metal crown was manufactured from a disk of polymethylmethacrylate resin, through CAD/CAM milling. The PMMA model was digitized by using an industrial CT in order to obtain the digital reference model. Afterwards, the resin model was scanned 15 times with each scanner, following manufacturer's instructions. In order to asses trueness, comparisons were performed with the digital reference model while, for precision, the first scan in the series was compared with the following scans. Results and disscusion. When the trueness of the included scanners was tested, the average deviation for the laboratory scanner was 9.85 μm and 20.85 μm, respectively, for the intraoral scanner. As for precision, the mean recorded deviations were 6.32 μm for the laboratory scanner and 17.18 μm for the intraoral scanner. For both fidelity and trueness, F and T tests demonstrate a statistically significant difference between the scanners. Conclusions. Within the limits of this study, we can state that a significant difference was observed between the accuracy displayed by the scanners tested in this study, mainly generated by the different capturing techniques used by each scanner. [ABSTRACT FROM AUTHOR]

The present study reviews the current scientific literature regarding the CAD/CAM technology for fabricating complete dentures. An electronic search was conducted for relevant articles, using PubMed database and Web of Science database, followed by manual search, with the following association of terms: (cad cam, complete denture) then (subtractive manufacturing, complete denture). The study included articles published between 01.01.2006 and 31.12.2016. A table especially designed for this review provided information on the accuracy, retention and stability, aesthetics and overall denture satisfaction. The CAD/CAM process offers significant advantages both to the dental practitioner and patient. [ABSTRACT FROM AUTHOR]

Abstract: Objectives: To assess the translucency of two pressable ceramics and to analyze their masking property when placed on different tooth‐shaded backgrounds. Materials and methods: Thirty discs (1‐mm thickness) were fabricated using two pressable ceramics (shade/translucency): 1M1T/HT, 1M2T/HT, 2M2T (VITA PM9), and A1LT/HT, B1LT/HT, A2LT (e.max Press). Color measurements of discs were performed with a dental spectrophotometer on tooth‐colored backgrounds (A1/A2/A3/A3.5/A4), and black and white backings. The masking property was calculated as the color difference (CIEDE2000) between parameters of discs on control (A1, A2) and test backgrounds (A3, A3.5, A4). One‐way ANOVA was used for assessing differences in translucency parameter (TP) between ceramics. Two‐way ANOVA was used for detecting differences among groups when measured over tooth‐shaded backgrounds (α = 0.05, Bonferroni correction). Results: TP ranged between 14.96 (B1LT) and 25.18 (1M1HT). A significant difference in TP was found between tested ceramics (F = 949.949, P < .001). However, TP did not vary significantly between 1M1HT and 1M2HT (P > .05), 1M1T, A1HT and B1HT (P > .05), 1M2T, 2M2T, and A2HT (P > .05). A significant interaction effect of underlying background on color of ceramic discs was found (F = 107.994, P < .001). Conclusion: VITA PM9 demonstrated higher translucency than e.max Press ceramics. Except A1LT, all ceramic materials evaluated showed poor masking properties on A4 background. Clinical Significance: Highly translucent ceramics should be wisely used for restoring the appearance of dental structures since background color has a large effect upon these materials. The more recently introduced pressable ceramics showed high levels of translucency. [ABSTRACT FROM AUTHOR]

The article highlights the main steps in directly obtaining of customized medical implants made of biometals, starting from computer tomography scanning of the patient up to the proper individualised implant, fabricate by Additive Manufacturing. To detail the entire design-manufacturing method, a 3D model was designed with specific software's, the osseous reconstruction was manufactured by selective laser melting (SLM) and post-processed. In order to investigate the surface of titanium implant, scanning electronic microscopy was used. The research exhibits a good SLM manufacturing practice regarding a zygomatic reconstruction implant. The advantages of customized implants are accurate, having aesthetic and functional results. This procedure described bellow could reduce the surgery and recovery time, and it could significantly improve the patient's life quality. [ABSTRACT FROM AUTHOR]

Objective: The main goal of the present study is to compare two methods for evaluating the marginal fit of fixed prosthetic restorations. For this purpose we used a milled ceramic material, out of which we obtained class I inlays. The marginal gap was analyzed using micro CT and electronic microscopy. Materials and methods: After extraction of four caries-free mandibular first molars, first class inlay cavities were prepared. The marginal gap was analyzed circumferentially at the occlusal margin using a Bruker micro CT, by measuring the distance at the occlusal limit of the cavities, between the restoration and the tooth in several points for every surface of each tooth before cementing. For the second method SEM technology was used, and measurements were made at the occlusal limit of the cavities, between the restoration and the tooth in 50 microns steps. The data were compared with One-way ANOVA with Tukey's Multiple Comparison Test performed using 5.00 for Windows (GraphPad Prism 5.00 Software, San Diego, California USA). Results and discussion: For both methods we obtained clinical acceptable values of the marginal gap for the milled ceramic inlays. The null hypothesis was rejected. We obtained statistical significant differences of the measured gaps using the two above mentioned methods. Conclusions: Both evaluation methods are reliable for measuring the marginal gap of fixed prosthetic restorations, each method having specific indications, advantages and disadvantages. They offer indispensable information which lead to improvement of the restorative treatments. [ABSTRACT FROM AUTHOR]

Aims. This study was conducted to assess the knowledge and degree of acceptance of dental CAD/CAM systems among oral healtcare providers in the city of Cluj- Napoca, Romania. Materials and methods. A questionnarebased survey containing 23 questions was distributed by means of a web-based social platform to the dentists practising in the city of Cluj-Napoca. 103 valid questionnaires from oral healthcare physicians with more than one year experience in clinical practice were obtained. Descriptive statistical analysis was performed and results were expressed as number and percentage for each question. Results and discussion. A significant percentage of dentists asserted they have theoretical knowledge about this technology (85.4%), while only nine dentists (8.73%) currently use CAD/CAM technology in their clinical practice. However, over 75% of the surveyed subjects intend to use at least an intraoral digital scanner in the next 5 years. Most of the surveyed clinicians consider that their profession is not affected by the introduction of subtractive manufacturing systems, however the role of the dental technicians is diminished by the introduction of this technology. Conclusions. At present, a relatively small number of oral health providers are using CAD/CAM systems in their clinical practice, even most of them plan to use this technology in the near future. [ABSTRACT FROM AUTHOR]

The clinical success of aesthetic ceramic fused to metal or composite resin bonded to metal restorations depends on the quality and strength of composite/ceramic bonding. To investigate the ceramic and composite surface adhesion to the surface of the alloys, samples were prepared by metallographic techniques and then were analyzed by Scanning Electron Microscopy (SEM). We studied a total of four samples of superalloys, denoted S1, S2, S3, and S4. Each of these was treated with: Vita ceramic powders, Noritake ceramic powders, Premise Indirect composite and an indigenous composite C1. At a magnification level of x1500, the adherence between the layers and the surface irregularities of the layers that improve the adherence could be properly observed. It is worth noting that after the sample preparation procedure, samples S1, S2 and S4 were damaged, the only sample remaining in a good condition was sample S3. [ABSTRACT FROM AUTHOR]

Radiological examination is indispensable in current dental practice. Lately, dentists have become not only the beneficiaries of radiographic investigations required for diagnosis, but also their authors, as many dental offices have been authorized to have X-ray machines and carry out radiological activity. This is why dentists who perform dental X-rays have the legal and moral obligation to possess thorough theoretical and practical knowledge about the radiological technique and also about their own and patients' radiation protection. This study investigates to what extent medical practitioners providing dental radiology services know and apply the technical norms for work and patient protection. [ABSTRACT FROM AUTHOR]

Purpose - This paper is intended to summarize the current available literature in which low-cost, open-source RepRap 3D printers are incorporated in the field of dentistry in an attempt to improve or replace conventional clinical and/or laboratory procedures. Methodology- An electronic search of publications from January 2004 to July 2014 was performed, by two researchers, in two electronic databases: Medline (PubMed) and EMBASE Library. All searches were limited to human subjects investigations, published in English. Search terms included general and specific terms from the field of dentistry and additive manufacturing. Findings - The contribution of RepRap 3D printers to the field of dentistry is so far limited to only two applications, respectively reconstruction of study models for orthodontic measurements and reconstruction of skull segments. Originality/value - This review brings focus on the few researches and applications of low-cost RepRap printers in the dental field. In spite of the promising results reported, there still remains a sizable sector in which the capabilities of these low-cost, open source 3d printers are to be tested. [ABSTRACT FROM AUTHOR]

Making a highly aesthetic, rapid and time-resistant prosthetic restoration, an objective which has always been a permanent goal for both clinicians and patients, is nowadays possible with the development of computer-aided techniques, including the CEREC system with its two versions: CEREC 3D and InLab. This paper presents the CEREC chair-side method and discusses its benefits and main characteristics. [ABSTRACT FROM AUTHOR]

The Cerec system (an acronym for Ceramic reconstruction) is a compact computer integrated imaging and milling system created to eliminate as much as possible human input and errors during various lab procedures. The main asset of this system is the ability to mill, fit, seat and finish a restoration in a single session. [1] The advantages of the Cerec system include a more economical restoration, comparatively with a conventional one, due to the cost savings generated by the elimination of conventional impression and temporary restoration. [ABSTRACT FROM AUTHOR]

The outcome of prosthetic restorations manufacturing in the field of dentistry and the remarkable functional results recorded depend equally on the accuracy of the clinical preparation and on the technology used. Currently, CAD-CAM systems represent the most advanced technology in restorative dentistry, which many practitioners consider to be the future of dentistry. This paper presents the operating procedure, the equipment and protocol used in the chair side and laboratory version of the CEREC system, summarizing the benefits it provides to both dental team and patients. [ABSTRACT FROM AUTHOR]

This study was concerned with the adhesion of resin cement to metal surfaces obtained by selective laser melting process (SLM), and how it could be improved the bond strength at the biocomposite-metal junction. The SLM substrates were manufactured out of pure titanium (Ti), Ti6Al7Nb, and CoCr alloys. The metallic surfaces were covered with 5 types of biocomposites: 2 commercially resin-modified glass-ionomer cements (GC Fuji Plus and KETAC CEM) and 3 types of in-house developed materials. These biocomposites were mechanical characterized under compression and bending trials. The biocomposites-metal adhesion was settled both on as built metallic surfaces and after they were sandblasted with alumina. All the sandblasted SLM surfaces presented higher adhesion strength in comparison with the untreated specimens. The CoCr specimens show the highest bonding value. Additionally, the morphological aspects of joining interfaces were investigated using a scanning electron microscope (SEM). The mechanical properties and metal adhesion of these biocomposites were influenced by the liquid powder ratio. It is essential to apply a surface treatment on SLM substrate to achieve a stronger bond. Also, the chemical composition of biocomposite is a major factor which may improve the adhesion of it on different metallic substrates. [ABSTRACT FROM AUTHOR]

Introduction. The aim of the study is to analyze the utility of real-time elastography (RTE) in diagnosing cervical cancer (CC) and cervical intraepithelial neoplasia (CIN), using an experimental device (ED) made from a synthetic material as benchmark of rigidity. Methodology. Seventy-nine patients were involved in the study, being divided into three groups: Group 1 – benign cervix (n=39); Group 2 – CIN (n=32); Group 3 – CC (n=8). Seventy-nine identical silicone DEs were created. RTE was performed and the strain ratio (SR) method was used to quantify stiffness, representing the ratio of stiffness between the analyzed cervical tissue and ED. The average SR values corresponding to each group were compared. The diagnostic performance of the method was evaluated by generating the ROC curve and analyzing the area under the curve (AUC). Cut-off values were set. The histopathological results were the benchmark for data interpretation. Results. The average value of SR for Group 1 was significantly different from that of Groups 2 and 3 (p=0.001). After the exclusion of two aberrant values from Group 3, attributed to complicated cases with hemorrhagic necrosis, significant differences of the average SR between Groups 2 and 3 were observed (p=0.02). For Groups 1 and 3, the AUC was 0.966, with 95% CI (0.914-1.000); the cut-off value of the SR was 1.42, with a sensitivity of 100% and a specificity of 94.9%. The AUC was 0.752, with 95% CI (0.629-0876) for Groups 1 and 2; the sensitivity and specificity were 75%, respectively 74% for the cut-off value of 1.03. Conclusions. RTE, quantified by SR, using a synthetic reference material, seems a reliable method of differentiating the benign cervix from the malignant one; the technique proves promising results as a complementary method in CIN evaluation and diagnosis. Nevertheless, SR becomes inoperative in cases of cancer complicated by extensive hemorrhagic necrosis. [ABSTRACT FROM AUTHOR]

Introducere. Elastografia este o tehnică imagistică ce apreciază rigiditatea structurilor şi care este complementară ultrasonografiei convenţionale. Metoda elastografică are în prezent o largă utilizare în evaluarea leziunilor mamare, tiroidiene şi prostatice. Scopul acestui studiu este de a evalua utilitatea elastografiei în timp real în analiza ţesutului cervical normal, precum şi a leziunilor preneoplazice şi neoplazice ale colului uterin. Materiale şi metodă. Au fost incluse în studiu 28 de paciente, repartizate în trei grupuri, după cum urmează: grupul A - fără leziuni ale colului uterin (n=10), grupul B - displazie col uterin (n=10), grupul C - neoplasm de col uterin (n=8), confirmate prin biopsie şi analiză anatomopatologică. Au fost realizate 28 de dispozitive identice din silicon de adiţie, cu dimensiuni de 35/10/10 mm, care au fost considerate reper al ridigităţii în evaluarea colului uterin. S-a realizat ecografie bidimensională cu sondă endovaginală pentru identificarea şi reperarea colului uterin şi a dispozitivului din silicon, poziţionat în proximitatea colului, urmată de elastografie în timp real. S-a calculat raportul de dislocare (Strain Ratio; SR) între colul uterin şi dispozitivul din silicon. Analiza datelor a fost realizată utilizând programul SPSS 16.0. Au fost comparate rezultatele SR din cele trei grupuri. Pentru fiecare pacientă, s-a considerat media a 10 determinări consecutive ale SR. Rezultate şi concluzii. Analiza datelor a indicat diferenţe semnificative (p<0,05) ale SR între toate cele trei grupuri, cu cele mai mici valori ale SR în grupul A şi cele mai mari valori pentru grupul C. În concluzie, elastografia în timp real, realizată cu sonda endovaginală, utilizând un dispozitiv din silicon ca reper, este o tehnică utilă în evaluarea rigidităţii colului uterin. Rezultatele acestui studiu sugerează capacitatea elastografiei de a diferenţia, neinvaziv, între leziunile preneoplazice şi neoplazice ale colului uterin. [ABSTRACT FROM AUTHOR]

Aims: To assess the usefulness of real time elastography (RTE) strain ratio (SR) in diagnosing cervical cancer (CC) and cervical intraepithelial neoplasia (CIN), using a synthetic experimental device (ED) as reference material.Material and Methods: Seventy-nine participants were enrolled, divided in three groups: Group 1 - benign cervix (n=39); Group 2 - CIN (n=32); Group 3 - CC (n=8). Transvaginal RTE was performed, with SR determination, as the ratio between the ED and the cervical tissue. Mean SR values of the groups were compared; diagnostic performance was assessed by tracing the receiver operating characteristic (ROC) curve. Area under the curve (AUC) was analyzed. Cut-off values were established. Pathological results were considered as reference for data interpretation.Results: SR means significantly differed in Group 1 as compared to Groups 2 and 3 (p=0.001). Excluding 2 aberrant values in Group 3, assigned to cases complicated by hemorrhagic necrosis, statistical difference was also noted between Groups 2 and 3 (p=0.02). For Groups 1 and 3, AUC was 0.966 with a 95%CI (0.914-1.000); the cut-off point of SR was 1.42, with a sensitivity of 100% and a specificity of 94.9%. AUC was 0.752 with a 95%CI (0.629-0.876) for Groups 1 and 2. For the cut-off value of 1.03, sensitivity and specificity were 75% and 74%, respectively.Conclusion: RTE SR, performed with a synthetic reference material, seems a reliable method for distinguishing between benign uterine cervix and malignancy, with promising results as a complementary investigation in diagnosing CIN. However, SR becomes inoperant in cases of cancer complicated with hemorrhagic necrosis. [ABSTRACT FROM AUTHOR]

Aims: To analyse the intra- and interobserver variability of two elastographic methods of quantification available on the same machine, the technical factors that may influence variability as well as the intra- and interobserver variability for the same indices between two different ultrasound machines in an in vitro experimental setting.Material and Methods: Three different types of silicone experimental devices (ED) were conceived for the purpose of this study. Two observers performed repeated measurements on two ultrasound machines. Strain elastography, with strain ratio determination between the ED was performed on both machines. Shear wave ratio was also assessed. The data obtained were used to calculate intra- and interobservervariability. Reproducibility was assessed in relation to the size of the elastographic region of interest (ROI) and to the difference in stiffness between the ED, through the value of the ICCs (Intraclass Correlation Coefficient).Results: Strain ratio had high inter- and intraobserver reproducibility, regardless of the machine used, on a large number of determinations.The choice of a small ROI diameter (5 mm) over a large ROI diameter (15mm) increased reproducibility (ICC = 0.87 vs 0.78, p=0.000). It is observed that, by Shear Wave Elastography, only when analysing structures with a large difference in hardness, significance is obtained in terms of interobserver reproducibility (ICC = 0.75, p=0.000).Conclusions: On a large number of determinations, both techniques are inter- and intraobserver reproducible. It is preferable to opt for a smaller ROI diameter in order to increase interobserver reproducibility. SWE Ratio provides significant reproducibility only when analysing structureswith large difference in hardness. [ABSTRACT FROM AUTHOR]