Aesthetic dentistry : chromatic appreciation in the clinic and the laboratory

Aesthetic requirement in dentistry is getting more and more important every day. One of its basic principles is the correct selection of colour for the restorations. Colour is a quality which is modulated by a series of factors, environmental and individual, that the clinic must know. Colour measurement by the human eye can induce to an appreciation mistake if it doesn?t follow a correct protocol of light conditions and observation technique, checked by the authors, simplifying it with a practical focusing. Colour measurement instruments have appeared recently, trying to correct the problems of conventional technique

Evaluación morfológica y morfométrica de las imágenes tomográficas retinianas como factor pronóstico del resultado visual en pacientes con neovascularización coroidea miópica

OBJETIVOS: Investigar el valor pronóstico de las características observadas en las imágenes tomográficas de la retina en pacientes con neovascularización coroidea miópica en tratamiento con ranibizumab intravítreo. METODOLOGÍA: Estudio retrospectivo, observacional y analítico sobre 25 ojos de 25 pacientes. Se estudiaron las imágenes de tomografía de coherencia óptica de estos pacientes valorando la presencia de un recubrimiento hiperreflectivo (tipo 1) sobre la membrana neovascular, frente a los que no lo presentan (tipo 2/3) como factor pronóstico. También se valoraron el estado de la membrana limitante externa y los elipsoides, el área de atrofia coriorretiniana, el grosor y volumen coroideo en diferentes localizaciones y el grosor retiniano. RESULTADOS: El tratamiento induce una mejora significativa de la agudeza visual a lo largo del seguimiento en la muestra general. La mejoría puede considerarse similar en ambos grupos de tipo de neovascularización coroidea miópica. Los pacientes con neovsacularización de tipo 2/3 exhiben siempre una mayor afectación de la agudeza, diferenciándose especialmente al mes de tratamiento y a los 12 meses de seguimiento. Es notable que estos pacientes experimentan una pérdida de agudeza a partir de los 6 meses, mientras el grupo de neovascularización coroidea de tipo 1 exhibe una recuperación siempre progresiva. El número de inyecciones no determina diferencias significativas en la evolución de la agudeza visual. Si bien se constata una tendencia a un mayor número de inyecciones en el grupo de neovascularización de tipo 2/3. CONCLUSIONES: De acuerdo con la clasificación sugerida, aquellos pacientes con recubrimiento hiperreflectivo (tipo 1) frente a los que no lo poseen (tipo 2/3) tendrían un relativo mejor pronóstico en términos de agudeza visual y necesidad de tratamiento con inyecciones intravítreas de ranibizumab. La medición de grosor coroideo bajo la membrana neovascular tiene valor pronóstico respecto a los resultados de agudeza visual. Son necesarios estudios más amplios que confirmen estos resultados.PURPOSE: To investigate the prognostic value of characteristics observed in retinal tomography images in patients with myopic choroidal neovascularization treated with intravitreal ranibizumab. METHODS: Retrospective, observational and analytical study on 25 eyes of 25 patients. Optical coherence tomography images of these patients were studied by evaluating the presence of a hyperreflective envelopment (type 1) on the neovascular membrane, compared to those that do not present it (type 2/3), as a prognostic factor. The state of the external limiting membrane and the ellipsoid zone layer, the area of chorioretinal atrophy, the choroidal thickness and volume in different locations and the retinal thickness were also evaluated. RESULTS: The treatment induces a significant improvement of visual acuity throughout the follow-up in the general sample. The improvement may be considered similar in both myopic choroidal neovascularization type groups. Patients with type 2/3 neovascularization always show a greater visual acuity affection, being most different one month after first treatment and at 12 months of follow-up. It is notable that these patients experience a loss of visual acuity after 6 months, while the type 1 choroidal neovascularization group exhibits an ever progressive recovery. The number of injections does not determine significant differences in the evolution of visual acuity. Although there is a tendency for a greater number of injections in the group of type 2/3 neovascularization. Regarding the other characteristics evaluated, there were no significant differences in the evolution of visual acuity or the need for treatment, except forthe measurement of choroidal thickness underneath the neovascular membrane, where greater thickness showed better visual acuity. CONCLUSIONS: According to the suggested classification, patients with hyperreflective envelopment (type 1) versus those who do not have it (type 2/3) would have a relative better prognosis in terms of visual acuity and need for treatment with intravitreal injections of ranibizumab . Measurement of choroidal thickness under the neovascular membrane has a prognostic value in terms of visual acuity results. Larger studies are needed to confirm these results

Relationship between resolution and accuracy of four intraoral scanners in complete-arch impressions

The scanner does not measure the dental surface continually. Instead, it generates a point cloud, and these points are then joined to form the scanned object. This approximation will depend on the number of points generated (resolution), which can lead to low accuracy (trueness and precision) when fewer points are obtained. The purpose of this study is to determine the resolution of four intraoral digital imaging systems and to demonstrate the relationship between accuracy and resolution of the intraoral scanner in impressions of a complete dental arch. A master cast of the complete maxillary arch was prepared with different dental preparations. Using four digital impression systems, the cast was scanned inside of a black methacrylate box, obtaining a total of 40 digital impressions from each scanner. The resolution was obtained by dividing the number of points of each digital impression by the total surface area of the cast. Accuracy was evaluated using a three-dimensional measurement software, using the ?best alignment? method of the casts with a highly faithful reference model obtained from an industrial scanner. Pearson correlation was used for statistical analysis of the data. Of the intraoral scanners, Omnicam is the system with the best resolution, with 79.82 points per mm2, followed by True Definition with 54.68 points per mm2, Trios with 41.21 points per mm2, and iTero with 34.20 points per mm2. However, the study found no relationship between resolution and accuracy of the study digital impression systems (P >0.05), except for Omnicam and its precision. The resolution of the digital impression systems has no relationship with the accuracy they achieve in the impression of a complete dental arch. The study found that the Omnicam scanner is the system that obtains the best resolution, and that as the resolution increases, its precision increases

Comparative characterization of a novel cad-cam polymer-infiltrated-ceramic-network.

Background: The field of dental ceramics for CAD-CAM is enriched with a new innovative material composition having a porous three-dimensional structure of feldspathic ceramic infiltrated with acrylic resins.The aim of this study is to determine the mechanical properties of Polymer-Infiltrated-Ceramic-Network (PICN) and compare its performance with other ceramics and a nano-ceramic resin available for CAD-CAM systems. Material and Methods: In this study a total of five different materials for CAD-CAM were investigated. A polymer- infiltrated ceramic (Vita Enamic), a nano-ceramic resin (Lava Ultimate), a feldspathic ceramic (Mark II), a lithium disilicate ceramic (IPS-e max CAD) and finally a Leucite based ceramic (Empress - CAD). From CAD-CAM blocks, 120 bars (30 for each material cited above) were cut to measure the flexural strength with a three-point- bending test. Strain at failure, fracture stress and Weibull modulus was calculated. Vickers hardness of each material was also measured. Results: IPS-EMAX presents mechanical properties significantly better from the other materials studied. Its strain at failure, flexural strength and hardness exhibited significantly higher values in comparison with the others. VITA ENAMIC and LAVA ULTIMATE stand out as the next most resistant materials. Conclusions: The flexural strength, elastic modulus similar to a tooth as well as having less hardness than ceramics make PICN materials an option to consider as a restorative materia

In vivo study of different methods for diagnosing pit and fissure caries

Background: In recent years the early detection of such caries has gained importance, since it may avoid unnecessary dental tissue damage and allow minimally invasive dental treatment. A study is made of 5 systems for diagnosing caries: traditional visual and tactile methods, DIAGNOdent, VistaProof and CarieScan. Material and Methods: A prospective study was made in the Department of Stomatology, Dental Pathology and Therapeutics Teaching unit of the University of Valencia (Valencia, Spain), involving the analysis of 32 teeth (molars or premolars of both arches scheduled for filling or for use as posts in dental bridges) in 28 patients. The following caries diagnostic methods were applied: visual, tactile, DIAGNOdent (KAvo, Biberach, Germany), VistaProof (Dürr Dental AG, Bietigheim-Bissingen, Germany) and CarieScan (IDMoS Dental Systems, Dundee, Scotland, United Kingdom). Fissurotomy was subsequently performed for histological validation. Results: Visual inspection showed an area under the receiver operating characteristic curve (AUC-ROC) of 0.75, with a sensitivity and specificity of 0.75. Tactile diagnosis in turn showed AUC = 0.714, with maximum sensitivity (100%) and a specificity of 42.9%. DIAGNOdent (cutoff point 22.5) and VistaProof (cutoff point 1.1) showed AUC = 0.969, while CarieScan (cutoff point 21.5) presented AUC = 0.973. These latter three methods all had a sensitivity of over 92%. The specificity of DIAGNOdent was maximum, while that of CarieScan and VistaProof was 75%. Conclusions: The emergent methods in the diagnosis of caries (DIAGNOdent, VistaProof and CarieScan) yielded similar results, and in all cases proved superior to the traditional visual and tactile methods. DIAGNOdent was seen to be the most effective technique, followed by CarieScan and VistaProof

Prophylactic effect of brimonidine to minimize the incidence of subconjunctival hemorrhage in the early postoperative period after 23G pars plana vitrectomy

Background: Several studies have investigated and demonstrated the prophylactic effect of brimonidine drops in preventing subconjunctival hemorrhage in some microincisional ophthalmic surgeries, such as intravitreal injections or cataract surgery. However, there are no previous studies investigating this prophylactic effect after 23G microincisional vitreoretinal surgery. Aim: The aim of the current study was to determine whether subconjunctival hemorrhage after 23G pars plana vitrectomy (PPV) could be prevented with the use of prophylactic topical brimonidine. Methods: This was a phase III, prospective, interventional, randomized, controlled single-center clinical trial with a follow-up of 2 weeks. A total of 77 eyes (mean age: 68.4 ± 10.7 years) undergoing 23G PPV were included and randomized into two groups: group 1 including 41 patients receiving prophylactic preoperative treatment with brimonidine, and group 2 (control group) including 36 patients not receiving this prophylactic treatment. Differences in terms of number of conjunctival quadrants affected with subconjunctival hemorrhage were evaluated in each of the follow-up visits. Results: The presence of subconjunctival hemorrhage was similar in both groups the first days after surgery (p > 0.05). At the last visit (10–14 days after surgery), this condition was significantly more frequent in control group where there was a significant difference, being more frequent in the control group (7.3% vs 28.6%, p = 0.022). The number of conjunctival quadrants affected was also similar in both groups, except for the last visit in which most of the patients treated with brimonidine (92.7%) showed no bleeding compared to 71.4% in control group. No effect on the efficacy of brimonidine treatment of the presence of blood hypertension, diabetes, and antiplatelet or anticoagulant treatment was observed. Conclusion: Brimonidine seems to be a useful option to decrease subconjunctival hemorrhage after microincisional vitreoretinal surgery or improve its resolution during the first postoperative week. This finding should be mainly due to the vasoconstrictor effect of brimonidine. Trial registration: EudraCT, 2012-002895-15 (registered 19 December 2012); https://www.clinicaltrialsregister.eu/ctr-search/search?query=2012-002895-15D.P.P. has been supported by the Ministry of Economy, Industry and Competitiveness of Spain within the program Ramón y Cajal, RYC-2016-20471

Accuracy of four digital scanners according to scanning strategy in complete-arch impressions.

STATEMENT OF PROBLEM:Although there are specific and general digital scanning guidelines depending on the system used, it is important to have the necessary flexibility in the acquisition of three-dimensional (3D) images to adapt to any clinical situation without affecting accuracy. PURPOSE:The purpose of this in vitro study was to identify and compare the scanning strategy with the greatest accuracy, in terms of trueness and precision, of four intraoral scanners in the impression of a complete dental arch. MATERIAL AND METHODS:Four digital scanners were evaluated with a 3D measuring software, using a highly accurate reference model obtained from an industrial scanner as a comparator. Four scanning strategies were applied 10 times on a complete maxillary arch cast inside a black methacrylate box. The data were statistically analyzed using one-way analysis of variance (ANOVA) and post hoc comparisons with Tamhane T2 test. RESULTS:The trueness of the Trios and iTero system showed better results with strategy "D," Omnicam with strategy "B," and True Definition with strategy "C". In terms of precision, both iTero and True Definition showed better results with strategy "D", while Trios showed best results with strategy "A" and Omnicam with strategy "B". There were significant differences between the scanning strategies (p0.05). CONCLUSIONS:The digital impression systems used in the experiment provided sufficient flexibility for the acquisition of 3D images without this affecting the accuracy of the scanner

Correction: Accuracy of four digital scanners according to scanning strategy in complete-arch impressions.

[This corrects the article DOI: 10.1371/journal.pone.0202916.]

Caries diagnosis using light fluorescence devices in comparison with traditional visual and tactile evaluation: A prospective study in 152 patients

The objective of the study was to evaluate the in vivo effectiveness of two fluorescence techniques (DIAGNOdent and VistaProof) and of visual and tactile evaluation in the diagnosis of occlusal caries in permanent teeth. A total of 302 teeth (molars and premolars) from 152 patients were studied. The occlusal surfaces were cleaned using pumice mixed with water, followed by application of the diagnostic methods according to the instructions of the manufacturer, and of the visual and tactile methods according to the recommendations. The true extent of the lesions was determined by fissurotomy. The sensitivity and specificity of visual diagnosis were 79 and 72 %, respectively, versus 53 and 98 % in the case of tactile diagnosis. Teeth with caries lesions exhibited significantly higher DIAGNOdent and VistaProof scores than those without caries. Using the optimum cutoff point of 23.5 obtained in our study for DIAGNOdent, sensitivity and specificity were found to be 92.4 and 92.7 %, respectively, while values of 88.1 and 95.1 % were obtained with a cutoff point of 28.5. Sensitivity in the case of the VistaProof system varied between 92.9 % (cutoff point 1.05) and 85.3 % (cutoff point 1.3), with respective specificity values of 95.8 and 88.6 %. The areas under the curve were 0.756, 0.759, 0.954 and 0.965 for the visual and tactile methods and for DIAGNOdent and VistaProof, respectively. The fluorescence-based techniques showed greater internal and external validity than the visual and tactile methods in diagnosing occlusal caries in permanent teeth. VistaProof is the best method for diagnosing caries in its early stages.Sin financiación1.458 JCR (2017) Q3, 51/91 Dentistry, Oral Surgery and MedicineUE