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OBJECTIVE: Incisal composite build-up shows a high failure susceptibility. The incorporation of fiber-reinforced composite (FRC) during composite restoration could improve its strength. Hence the study was planned to compare the effect of various positions of FRC on the strength of composite resin incisal build-ups. METHODS: In maxillary incisors (n = 90), 3 mm of the incisal edge was cut and teeth were categorized into three groups based on the location and number of fibers used during incisal composite build-up - Group I: composite resin; Group II: composite resin and a single fiber palatally and Group III: composite resin along with two fibers palatally. RESULTS: The data showed that group II had the maximum load-bearing values followed by group I and group III. CONCLUSION: Within the confines of our study, it can be concluded that the addition of FRC to the conventional incisal composite build-up increased the overall strength restoration. Such composite restoration reinforced with a single fiber on the palatal side showed the highest load-bearing capacity compared to two fibers reinforced and unreinforced composites. The common mode of failure in group I was in composite resin, in two fibers reinforced at fibers-composite junction, and in one fiber reinforced composite was in the remaining part of the tooth.
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Biomimética , Projetos de Pesquisa , Humanos , Resinas Compostas/uso terapêutico , IncisivoRESUMO
BACKGROUND: Vinyl polyether silicone (VPES) is a novel impression biomaterial made of a combination of vinyl polysiloxane (VPS) and polyether (PE). Thus, it is significant to assess its properties and behaviour under varied disinfectant test conditions. This study aimed to assess the dimensional stability of novel VPES impression material after immersion in standard disinfectants for different time intervals. METHODS: Elastomeric impression material used -medium body regular set (Monophase) [Exa'lence GC America]. A total of 84 Specimens were fabricated using stainless steel die and ring (ADA specification 19). These samples were distributed into a control group (n=12) and a test group (n=72). The test group was divided into 3 groups, based on the type of disinfectant used - Group-A- 2% Glutaraldehyde, Group-B- 0. 5% Sodium hypochlorite and Group-C- 2% Chlorhexidine each test group was further divided into 2 subgroups (n=12/subgroup) based on time intervals for which each sample was immersed in the disinfectants - subgroup-1- 10 mins and Subgroup 2- 30 mins. After the impression material was set, it was removed from the ring and then it was washed in water for 15 seconds. Control group measurements were made immediately on a stereomicroscope and other samples were immersed in the three disinfection solutions for 10 mins and 30 mins to check the dimensional stability by measuring the distance between the lines generated by the stainless steel die on the samples using a stereomicroscope at x40 magnification. RESULTS: The distance measured in the control group was 4397.2078 µm and 4396.1571 µm; for the test group Group-A- 2% Glutaraldehyde was 4396.4075 µm and 4394.5992 µm; Group-B- 0. 5% Sodium hypochlorite was 4394.5453 µm and 4389.4711 µm Group-C- 2% Chlorhexidine was 4395.2953 µm and 4387.1703 µm respectively for 10 mins and 30 mins. Percentage dimensional change was in the range of 0.02 - 0.25 for all the groups for 10 mins and 30 mins. CONCLUSIONS: 2 % Glutaraldehyde is the most suitable disinfectant for VPES elastomeric impression material in terms of dimensional stability and shows minimum dimensional changes as compared to that of 2% Chlorhexidine and 0.5% Sodium hypochlorite.
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Materiais para Moldagem Odontológica , Glutaral , Teste de Materiais , Polivinil , Siloxanas , Materiais para Moldagem Odontológica/química , Polivinil/química , Siloxanas/química , Fatores de Tempo , Glutaral/química , Desinfetantes de Equipamento Odontológico/química , Hipoclorito de Sódio/química , Desinfetantes/química , Clorexidina/química , Propriedades de Superfície , HumanosRESUMO
BACKGROUND: Periodontal phenotype is regarded to be one of the key factors influencing the efficacy of restorative therapies in dental practice. The objective of the systematic review was to explore the importance of thin and thick periodontal phenotypes and how they affect the outcome of periodontal and restorative therapies by looking at a number of academic publications from various online databases. METHODS: Following the PRISMA guidelines (Preferred Reporting Items for Systematic Review standards), relevant data will be searched and retrieved from three significant scientific databases, including PubMed, EBSCO, and Scopus. The articles with full texts that matched the keywords and published in English between 2018 and 2023 were taken into consideration. RESULTS: The majorities of these articles were based on the type of periodontal phenotype and their impact on periodontal and restorative treatment outcomes were selected. The initial search yielded a total of 530 articles. Only 273 were relevant to the review's objectives, and these were considered for determining eligibility. Only 20 publications were eligible for analysis. CONCLUSION: Understanding these anatomical aspects of periodontal phenotype is crucial to both periodontology and restorative dentistry. The clinical outcome of restorative, prosthetic, orthodontic, surgical, and periodontal therapies is determined in large part by the periodontal phenotype, which also plays a significant role in clinical failure or success in dental treatments. TRIAL REGISTRATION: This study protocol registered with the International Prospective Register of Systematic Reviews (PROSPERO) dated 16th June 2023 with the registration ID CRD42023432568.
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Assistência Odontológica , Periodontia , Humanos , Bases de Dados Factuais , FenótipoRESUMO
INTRODUCTION: This is an in vitro study to evaluate the degree of conversion (DC) of nanoceramic and microhybrid composites activated by different polymerization modes at different intervals. AIM: To determine the DC of two resin composites at different time intervals and modes of polymerization on DC. MATERIALS AND METHODS: Two commercially available composite resins-nanoceramic (Ceram X, Dentsply) and microhybrid (Spectrum TPH, Dentsply)-were used in this study. A total of 80 cylindrical samples (n = 40 each) were made by packing the composites in one increment into (5 × 2 mm) Teflon molds and cured using a light-emitting diode (LED) at an irradiance of 1,200 mW/cm2. Each group was further divided into two groups (n = 20) based on the curing modes (20 seconds, 40 seconds). These 20 samples were further subdivided (n = 10) based on the time interval (2 days, 7 days). Degree of conversion was assessed by Fourier-transform infrared spectrophotometer (FTIR) using a direct technique (attenuated total reflectance) on the top surface of the samples. Degree of conversion was measured for samples cured for 20 seconds (n = 10) and 40 seconds (n = 10) after 2 days and 7 days during which the samples were stored in an incubator at 37°C, 90% ± 10% relative humidity. The results obtained were statistically analyzed using two-way and three-way analysis of variance (ANOVA) test and p value set at (<0.005) significance level. RESULTS: Degree of conversion for the tested composites varied between 44% and 55% for Ceram X and 42% and 45% for Spectrum TPH. A significant difference was observed in DC for Ceram X samples for different polymerization modes (20 seconds and 40 seconds) as well as at 2-7 days measurement, whereas Spectrum TPH did not show any significant difference for polymerization modes. CONCLUSION: Ceram X demonstrated high DC values compared with that of Spectrum TPH with regard to two different polymerization modes. CLINICAL SIGNIFICANCE: Lesser the time required for conversion and less the residual monomer left, better is the prognosis of the restoration, and better is the patient satisfaction.
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Resinas Acrílicas , Resinas Compostas , Poliuretanos , Análise de Variância , Humanos , Teste de Materiais , Polimerização , Espectroscopia de Infravermelho com Transformada de FourierRESUMO
PURPOSE: To evaluate in vitro the effect of the size of the unfilled space of the abutment screw access hole on the amount of extruded excess cement and the retention of zirconia copings. MATERIALS AND METHODS: Twelve dental implant replicas were attached to the corresponding abutments and embedded in acrylic resin blocks. A total of 36 CAD/CAM zirconia copings were fabricated by one technician using the standard technique. Abutments were divided into group I: the entire screw access channel was completely filled (nonspaced); group II: 1-mm-spaced; and group III: 2-mm-spaced. The copings were air-abraded and temporarily cemented under constant load of 60 N for 10 minutes. The excess cement was calculated as the difference between the post-cementation and post-excess-removal weights using a digital scale. Retention test was performed by a universal testing machine at a 0.5 mm/min crosshead speed. The ultimate force and tensile strength required for separation were recorded. One-way ANOVA and Tukey's test were used for statistical analysis at p Ë 0.05. RESULTS: The average amount of extruded cement in groups 1, 2, and 3 was 33.48 ± 1.55, 23.05 ± 5.48, and 15.58 ± 5.98 mg, respectively. Multiple comparisons showed significant differences in the amount of extruded excess cement between the three groups (p Ë 0.001). The maximum load at decementation in groups 1, 2, and 3 was 98.8, 87.5, and 88.6 N, respectively. Groups 1, 2, and 3 separated at 6.90 ± 1.2, 6.12 ± 0.7, and 6.21 ± 0.9 MPa, respectively, with no significant differences between them. CONCLUSIONS: The amount of extruded excess cement was reduced by more than half when a 2-mm space of the screw access hole was left unfilled in comparison to the nonspaced counterpart. The retention of zirconia copings was not affected by the reported technique.
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Parafusos Ósseos , Coroas , Dente Suporte , Cimentos Dentários/química , Retenção em Prótese Dentária/métodos , Prótese Dentária Fixada por Implante , Desenho Assistido por Computador , Planejamento de Prótese Dentária , Análise do Estresse Dentário , Resistência à Tração , Zircônio/químicaRESUMO
STATEMENT OF PROBLEM: The detrimental effect of extruded excess cement on peri-implant tissue has been well documented. Although several techniques have been proposed to reduce this effect by decreasing the amount of extruded cement, how the space size of the abutment screw access channel (SAC) affects the amount of extruded cement and marginal accuracy is unclear. PURPOSE: The purpose of this in vitro study was to evaluate the effect of the size of the unfilled space of the abutment SAC on the amount of extruded excess cement and the marginal accuracy of zirconia copings. MATERIAL AND METHODS: Twelve implant replicas and corresponding standard abutments were attached and embedded in acrylic resin blocks. Computer-aided design and computer-aided manufacturing (CAD-CAM) zirconia copings with a uniform 30-µm cement space were fabricated by 1 dental technician using the standard method. The copings were temporarily cemented 3 times at different sizes of the left space of the SAC as follows: the nonspaced group (NS), in which the entire SAC was completely filled, the 1-mm-spaced group (1MMS), and the 2-mm-spaced group (2MMS). Abutments and crowns were ultrasonically cleaned, steam cleaned, and air-dried. The excess cement was collected and weighed. To measure the marginal accuracy, 20 measurements were made every 18 degrees along the coping margin at ×300 magnification and compared with the pre-cementation readings. One-way ANOVA was calculated to determine whether the amount of extruded excess cement differed among the 3 groups, and the Tukey test was applied for multiple comparisons (α=.05). RESULTS: The mean weights (mg) of extruded excess cement were NS (33.53 ±1.5), 1MMS (22.97 ±5.4), and 2MMS (15.17 ±5.9). Multiple comparisons showed significant differences in the amount of extruded excess cement among the 3 test groups (P<.001). The mean marginal discrepancy (µm) of the pre-cemented group (29.5 ±8.2) was significantly different (P<.01) from that of the NS (72.3 ±13.7), the 1MMS (70.1 ±19), and the 2MMS group (70.1 ±18.8). No significant differences were found in marginal accuracy among the 3 test groups (P=.942). CONCLUSIONS: Within the limitations of this in vitro study, leaving a 2-mm space in the SAC reduced the amount of extruded excess cement by 55% in comparison with the nonspaced abutments. However, no effect was found on the marginal accuracy of zirconia copings.
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Dente Suporte , Cimentos Dentários/uso terapêutico , Projeto do Implante Dentário-Pivô/métodos , Adaptação Marginal Dentária , Restauração Dentária Permanente/métodos , Desenho Assistido por Computador , Planejamento de Prótese Dentária , Humanos , Técnicas In VitroRESUMO
BACKGROUND: The radiation released at the time of dental panoramic radiographs causes genotoxic and cytotoxic effects on epithelial cells. OBJECTIVE: This research aimed to evaluate the changes in the frequencies of micronucleated cells in patients' buccal epithelial cells following dental panoramic radiography. METHODS: 74 patients were recruited for the study who were advised for panoramic radiographs. Using a wooden spatula, the buccal epithelial cells were scraped from both cheeks before to panoramic radiation exposure and ten days after the panoramic radiation exposure. Giemsa stain was used to stain the cells, and 500 cells were scored on a slide to determine the frequency of micronuclei. To determine the difference between the frequency of micronuclei before and after radiation exposure, a paired t-test was used in the statistical analysis. RESULTS: The proportion of micronuclei cells was 0.11% before radiation exposure and 0.57% following radiation exposure after 10 days. A statistically significant increase in the frequencies of micronuclei was noted after radiation exposure values. CONCLUSION: This study revealed the genotoxicity of epithelial cells with dental panoramic radiation exposure. It is advised to reduce the use of such radiographs and to use only when there is no other diagnostic tool that is helpful or when absolutely essential.
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Células Epiteliais , Testes para Micronúcleos , Mucosa Bucal , Radiografia Panorâmica , Humanos , Radiografia Panorâmica/efeitos adversos , Mucosa Bucal/efeitos da radiação , Mucosa Bucal/diagnóstico por imagem , Mucosa Bucal/citologia , Masculino , Feminino , Células Epiteliais/efeitos da radiação , Adulto , Pessoa de Meia-Idade , Micronúcleos com Defeito Cromossômico/efeitos da radiação , Adulto JovemRESUMO
BACKGROUND: Dental education is considered as a complex, challenging and often stressful educational procedure. Acquisition of psychomotor skills by undergraduate students is an important step in many health professions to become a successful professional. During under graduation, class II cavity preparation exercise is of utmost important in dentistry. OBJECTIVE: To compare class II cavities prepared by students after hands-on live demonstration and pre-recorded video demonstration using well-organised evaluation rubrics. METHOD: Preclinical dental students (n= 50) were divided into two groups. The students in group I (n= 25) attended a hands-on live demonstration performed by one faculty while students in group II (n= 25) watched a 15-minute pre-recorded procedural video on the projector. Both groups were appealed to prepare class II cavity for amalgam involving disto-occlusal surface of mandibular second molar articulated on jaw model (TRU LON study model, Jayna industries, Ghaziabad U.P., India). Following completion of the preparations, all teeth were collected, and labelled grades of prepared cavities were given according to prespecified rubrics. The data of scores were presented as means and standard deviation. Statistical analysis of data was executed using SPSS software. A paired t-test was used to compare scores between groups. RESULTS: The study shows that the video-supported demonstration of a cavity preparation was better than the live hands-on demonstration. A higher mean response for the procedural video group was found compared to the live demonstration group (p= 0.000133). CONCLUSION: Pre-recorded video-supported demonstration along with guidance by a tutor may be a viable alternative to hands-on live demonstration in cavity preparation procedures during undergraduate dental training. Moreover, rubric methods can be implemented in the teaching of various preclinical exercises for conservative dentistry and endodontics.
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BACKGROUND: Minimally invasive periodontic (perio) surgical procedures, piezocision, and micro-osteoperforation are useful techniques for accelerating tooth movement. These techniques also offer advantages in the orthodontic (ortho) and aesthetic domains. This study aimed to evaluate and compare the rates of lower anterior decrowding with piezocision and micro-osteoperforation. METHODS: This clinical study included 24 patients requiring fixed orthodontic treatments. Two periodontic techniques (piezocision (PZ) and micro-osteoperforation (MOP)) were considered for the orthodontic treatments. Each patient was randomly allocated to either the piezocision (PZ) group or the micro-osteoperforation (MOP) group. The piezocision group received five radiographically guided incisions on the labial surface of the alveolar bone, whereas the micro-osteoperforation group received one to three MOPs each using a mini-implant drill between the six lower anterior teeth, and later, an initial arch wire was ligated to each bracket. Little's irregularity index (LII) was calculated using a digital vernier caliper on study models every four weeks until decrowding was achieved. The difference in the rates of lower anterior crowding between the piezocision and micro-osteoperforation groups was analyzed to determine the statistical significance. RESULTS: The rates of irregularity index change during decrowding were 4.38 ± 0.61 in the piezocision group and 3.82 ± 0.47 in the micro-osteoperforation group. Piezocision was found to be 1.2 times faster than micro-osteoperforation in terms of the rate of decrowding. CONCLUSION: The advanced perio-ortho combination technique was advantageous in accelerated decrowding. In comparison to MOP, there was an increase in the rate of decrowding with PZ. Decrowding can be completed quickly with PZ, and it can thus be used to treat crowding effectively in a limited time frame.
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Background: The internet serves as a vital health information resource, yet the quality of data on specific health conditions, especially in Arabic, is often overlooked. This research assesses the quality of Arabic online information about cleft lip and palate (CLP) and proposes avenues for enhancement. Methods: From July to August 2022, a systematic evaluation of Arabic articles on CLP was performed using the DISCERN tool for quality assessment. Searches on Google and Bing resulted in 119 articles that met the study's criteria. Results: The quality of available Arabic information on CLP displayed substantial gaps. Commercial sources dominated (49.6%), followed by private (32.8%) and nonprofit entities (17.6%). The average DISCERN score was 2.26 of 5 (SD = 1.06), indicating the need for enhanced content, particularly concerning treatment risks. Conclusions: The study underscores the subpar quality of Arabic CLP information online, which might mislead patients and impede access to accurate advice. Nonprofit organizations should bolster their online footprint, offering refined health content. A deep dive into DISCERN scores reveals pinpointed improvement areas. Clinicians should direct patients and their families to reliable information sources. Addressing these gaps promises improved CLP knowledge in Arabic, fostering superior patient education and outcomes for those with this condition.
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BACKGROUND: At present, the evidence regarding digital impressions' accuracy recorded by using digital scanners is lacking. This systematic review aimed to evaluate whether the type of scanning (intraoral/extraoral) affects the Accuracy of Digital Impressions. METHOD: Two independent reviewers performed a systematic search in the database both electronically and manually (PubMed, Ebsco HOST, the Cochrane Library, and Google Scholar) for articles published from 1 January 2010 to 1 December 2022. This study was registered with the International Prospective Register of Systematic Reviews (PROSPERO CRD42020188765) and followed the PRISMA statement. The question in focus was as follows: Does the type of scanning (intraoral or extraoral) affect the accuracy of digital impression? RESULTS: A total of 449 papers were obtained by searching electronically and manually. In total, 15 complete-text papers qualified for assessment based on eligibility criteria. After reading the full-text articles, five studies were excluded. Ten studies were selected for the qualitative analysis. The qualitative data reported that the accuracy of both types of scanners (intraoral and extraoral) lies within the range of clinical acceptability. Nevertheless, the intraoral scanners seem to be more accurate when compared to the extraoral scanners for a partial arch situation. CONCLUSIONS: Scanning type affects the accuracy of the digital impression. Various factors influence the scanning ability. Intraoral scanners seem to be more accurate compared to extraoral scanners for a partial arch situation. More studies comparing the accuracy of the intraoral scanner and extraoral scanner for a complete arch scan and in an in vivo study setting are needed.
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This prospective quasi-experimental study from the NASAM (National Approach to Standardize and Improve Mechanical Ventilation) collaborative assessed the impact of evidence-based practices including subglottic suctioning, daily assessment for spontaneous awakening trial (SAT), spontaneous breathing trial (SBT), head of bed elevation, and avoidance of neuromuscular blockers unless otherwise indicated. The study outcomes included VAE (primary) and intensive care unit (ICU) mortality. Changes in daily care process measures and outcomes were evaluated using repeated measures mixed modeling. The results were reported as incident rate ratio (IRR) for each additional month with 95% confidence interval (CI). A comprehensive program that included education on evidence-based practices for optimal care of mechanically ventilated patients with real-time benchmarking of daily care process measures to drive improvement in forty-two ICUs from 26 hospitals in Saudi Arabia (>27,000 days of observation). Compliance with subglottic suctioning, SAT and SBT increased monthly during the project by 3.5%, 2.1% and 1.9%, respectively (IRR 1.035, 95%CI 1.007-1.064, p = 0.0148; 1.021, 95% CI 1.010-1.032, p = 0.0003; and 1.019, 95%CI 1.009-1.029, p = 0.0001, respectively). The use of neuromuscular blockers decreased monthly by 2.5% (IRR 0.975, 95%CI 0.953-0.998, p = 0.0341). The compliance with head of bed elevation was high at baseline and did not change over time. Based on data for 83153 ventilator days, VAE rate was 15.2/1000 ventilator day (95%CI 12.6-18.1) at baseline and did not change during the project (IRR 1.019, 95%CI 0.985-1.053, p = 0.2812). Based on data for 8523 patients; the mortality was 30.4% (95%CI 27.4-33.6) at baseline, and decreased monthly during the project by 1.6% (IRR 0.984, 95%CI 0.973-0.996, p = 0.0067). A national quality improvement collaborative was associated with improvements in daily care processes. These changes were associated with a reduction in mortality but not VAEs. Registration The study is registered in clinicaltrials.gov (NCT03790150).
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Respiração Artificial , Desmame do Respirador , Humanos , Unidades de Terapia Intensiva , Estudos Prospectivos , Respiração Artificial/métodos , Desmame do Respirador/métodos , Ventiladores MecânicosRESUMO
The photokinetic behaviour of drugs driven by polychromatic light is an area of pharmaceutics that has not received a lot of attention. Most often, such photokinetic data is treated by thermal kinetic models (i.e., the classical 0th-, 1st- or 2nd-order equations). Such models were not analytically derived from the rate-laws of the photodegradation reactions. Polychromatic light kinetic modelling is hence of importance, as a means to providing adequate toolkits and metrics. This paper aims at proposing two reliable drug-actinometers useful for polychromatic UVA range. The general actinometric methodology offered here is also useful for any drugs/materials obeying a primary photoprocess where both reactant and photoproduct absorb the incident light, of the [Formula: see text] type. The present method has been consolidated by the η-order kinetics. This framework further demonstrated the lamp-specificity of actinometers. Overall, Dacarbazine and Nifedipine photodegradations obeyed η-order kinetics, and stand as effective actinometers that can be recommended for the ICH Q1b photostability testing.
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Dacarbazina , Nifedipino , Cinética , Luz , Fotólise , Raios UltravioletaRESUMO
BACKGROUND: The growing accessibility to smartphones has raised concerns about addictive patterns associated with these technologies. A Smartphone Addiction Scale has been developed to assess individuals' smartphone addiction. However, the psychometric properties of the Smartphone Addiction Scale are scarce in the context of Saudi Arabia. AIMS: This study aimed to translate and adapt the Smartphone Addiction Scale (SAS) to Arabic and examine the psychometric properties of the Arabic scale in the context of Saudi Arabia. METHODS: Forward and backward translations were performed on the English SAS, as recommended by the World Health Organization (WHO, 2016). The translated version was initially administered to 20 students in a pilot study. In the full study, a sample of 624 participants (52.5% females, mean age = 25 years) responded to questionnaires containing SAS, the Hospital Anxiety and Depression Scale, and the Smartphone Application-Based Addiction Scale. The survey was sent via online platforms in order to reach as many and diverse participants as possible. Exploratory and confirmatory factor analyses were conducted. RESULTS: The EFA resulted in a structure of six factors and the CFA indicated that the 6-factor model (daily disturbance, positive anticipation, withdrawal, cyberspace-oriented relationships, overuse, and tolerance) had a good fit in Saudi Arabia (CFI = 0.92, TLI = 0.90, RMSEA = 0.04, SRMR = 0.04). The scale was also gender invariant and exhibited adequate reliability and convergent and concurrent validity. CONCLUSIONS: The SAS is a reliable and valid measure that can be used to assess smartphone addiction in Saudi Arabia.
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Transtorno de Adição à Internet , Smartphone , Adulto , Feminino , Humanos , Transtorno de Adição à Internet/diagnóstico , Masculino , Projetos Piloto , Psicometria , Reprodutibilidade dos Testes , Arábia Saudita , Inquéritos e QuestionáriosRESUMO
NASAM (National Approach to Standardize and Improve Mechanical Ventilation) is a national collaborative quality improvement project in Saudi Arabia. It aims to improve the care of mechanically ventilated patients by implementing evidence-based practices with the goal of reducing the rate of ventilator-associated events and therefore reducing mortality, mechanical ventilation duration and intensive care unit (ICU) length of stay. The project plans to extend the implementation to a total of 100 ICUs in collaboration with multiple health systems across the country. As of March 22, 2019, a total of 78 ICUs have registered from 6 different health sectors, 48 hospitals, and 27 cities. The leadership support in all health sectors for NASAM speaks of the commitment to improve the care of mechanically ventilated patients across the kingdom.
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A new Φ-order kinetic method was proposed in this study for the investigation of trans-cis photoisomerization reaction of Oxyresveratrol (ORVT) subjected to non-isosbestic irradiation. In ethanolic media, it has been proven that forward (ΦAâBλirr) and reverse (ΦBâAλirr) reaction quantum yields were dependent on the monochromatic irradiation wavelength according to sigmoid patterns over the spectral ranges of their electronic absorption (260-360nm). An 11.4- and 6.6-fold increases were recorded for ΦBâAλirr and ΦAâBλirr, respectively. The efficiencies of the former (ΦBâAλirr, ranging between 2.3×10-2 and 26.3×10-2) were 33 to 60% smaller than those of the respective ΦAâBλirr measured at the irradiation wavelengths selected. Overall, between 57 and 97% degradation of the initial trans-ORVT was observed under relatively weak light intensities, with the highest values recorded at the longest wavelengths. These findings strongly recommend protection from light in all situations of this biologically important phytomolecule that possesses therapeutic value of interest to pharmaceutical applications. The Φ-order kinetics also offered a simple way to develop a reliable actinometric method that proved ORVT to be an efficient actinometer for the dynamic range 295-360nm. The usefulness of Φ-order kinetics for the investigation and quantification of phytoproducts' photodegradation was discussed.
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Luz , Fotólise , Extratos Vegetais/química , Espectrofotometria , Estilbenos/química , Elétrons , Isomerismo , Cinética , Teoria Quântica , Soluções , TermodinâmicaRESUMO
INTRODUCTION: Eco-friendly or green dentistry can be a reality by effectively designing dental clinics and using more eco-friendly materials in the clinical practice. AIM: To determine the awareness of eco-friendly dentistry among dental faculty and students in preparation for future implementation. MATERIALS AND METHODS: Assessment of knowledge regarding eco-friendly dentistry was done using an 18 item self-administered questionnaire among 160 participants. After baseline data collection, the intervention was done by educating participants with a power point presentation. The post-intervention data was then collected for analysis. Statistical analysis was done using Wilcoxon's signed rank test and one-way ANOVA. RESULTS: The educational intervention increased the knowledge about eco-friendly dentistry confirming the importance of continuing education. There was a statistically significant gain in knowledge among the participants after the presentation. The gain was highest for department of Preventive Dental Sciences (PDS) followed by Substitute Dental Sciences (SDS), No specialty, Maxillofacial Dental Sciences (MDS), and Restorative Dental Sciences (RDS) respectively. (F=5.5091, p<0.05). CONCLUSION: Lack of knowledge of green dentistry amongst the dental fraternity is highly prevailing. The same can be substantiated with effective training in the respective fields if channelized through the curriculum in an educational set-up.
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OBJECTIVES: To determine the occurrence of smile line and maxillary tooth shape in the Saudi Arabian subpopulation, and to estimate the association between these parameters with gingival biotype. MATERIALS AND METHODS: On the fulfillment of selection criteria, total 315 patients belong to Saudi Arabian ethnic group were randomly selected. Two frontal photographs of the patients were acquired. The tooth morphology, gingival angle, and smile line classification were determined with ImageJ image analyzing software. The gingival biotype was assessed by probe transparency method. The obtained data were analyzed with SPSS 19 (IBM Corporation, New York, USA) software to determine the frequency and association between other parameters and gingival biotype. RESULTS: Among the clinical parameters evaluated, the tapering tooth morphology (56.8%), thick gingival biotype (53%), and average smile line (57.5%) was more prevalent. The statistically significant association was found between thick gingival biotype and the square tooth, high smile line. The high gingival angle was associated with thin gingival biotype. CONCLUSIONS: The study results indicate the existence of an association between tooth shape, smile line, and gingival angle with gingival biotype.
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Objective: The purpose of this study was to evaluate the knowledge among dental students at King Khalid University, Jazan University, and Najran University in the kingdom of Saudi Arabia about when to repair or replace defective direct composite restoration. Materials and Methods: A questionnaire-based survey was formulated, pursuing the information about management (repair/replacement) of defective composite restorations and distributed among 200 dental students of three universities in the southern region of the kingdom of Saudi Arabia. The data were collected with the help of an online questionnaire. Data entry and the analysis were done using the statistical software package SPSS version 20.0. It was presented using descriptive statistics in the form of frequencies and percentages for qualitative variables, and range means and standard deviations for age, quantitative variable. Analytic statistics were done using Chi-Square tests (χ2) to test the significant difference between categorical variables. The level of significance, the p-value was 0.01(p<0.01). Results: The decision to choose between composite repair or replacement was influenced by whether this topic was taught to them at various undergraduate levels during Bachelor of Dental Surgery. The reason associated with the decision to repair defective composite restorations, 76% reported as cost-effective followed by Increased longevity (71%), the permanent filling (70%), patient's preference for repair (65%), and least time consuming (50%). 67% participants preferred significantly (p<0.001) repair due to secondary caries in the previously restored tooth with composite, followed by the small surface defect in a composite restoration (65%), risk of pulpal damage significantly (p<0.001) in a defective composite restoration (62.5%) and more invasive and destructive treatment option (35%). More than half of respondents 123 (61.5%) reported that they were not taught about composite repair during the Bachelor of Dental Surgery. Conclusion: It is suggested with the help of our study that didactic and clinical training components regarding composite repair should be seriously included in the teaching curriculum of dental institutions as it is in the best interest of the patient. Dental students should be provided with clinical training on this topic so that they can follow proper decision-making protocols available during repair or replacement of defective resin composite restorations. Other researches in the future can be carried out for refining the guidelines and techniques utilized for composite repair. (AU)
Objetivo: O objetivo deste estudo foi avaliar o conhecimento entre estudantes de odontologia da King Khalid University, Jazan University e Najran University, no reino da Arábia Saudita, sobre quando reparar ou substituir restaurações de resina composta direta defeituosas. Material e Métodos: Foi formulada uma pesquisa baseada em questionário, buscando informações sobre o manejo (reparo / substituição) de restaurações de resina composta e distribuída entre 200 estudantes de odontologia de três universidades da região sul do reino da Arábia Saudita. Os dados foram coletados com o auxílio de um questionário online. A entrada e análise dos dados foram feitas com o software estatístico SPSS versão 20.0. Foi apresentado por meio de estatística descritiva na forma de frequências e percentuais para as variáveis qualitativas, e amplitude de médias e desvios-padrão para a idade, variável quantitativa. A estatística analítica foi feita usando testes de qui-quadrado (χ2) para testar a diferença significativa entre as variáveis categóricas. Ao nível de significância, o valor de p foi de 0,01 (p <0,01). Resultados: A decisão de escolher entre o reparo ou substituição do compósito foi influenciada pelo fato de este tópico ter sido ensinado a eles em vários níveis de graduação durante o Bacharelado em Odontologia. O motivo associado à decisão de reparar restaurações de resina composta defeituosas, 76% relataram como custo-benefício seguido por maior longevidade (71%), restauração definitva (70%), preferência do paciente para reparo (65%) e menos demorado ( 50%). Sessenta e sete por cento dos participantes preferiram o reparo significativamente (p <0,001) devido a cárie secundária no dente previamente restaurado com resina composta, seguido pelo pequeno defeito de superfície em uma restauração composta (65%), risco de dano pulpar significativamente (p <0,001) em um restauração de resina composta com defeito (62,5%) e opção de tratamento mais invasiva e destrutiva (35%). Mais da metade dos entrevistados, 123 (61,5%) relataram que não foram ensinados sobre reparo de resina composta durante o Bacharelado em Odonotlogia. Conclusão: É sugerido com a ajuda de nosso estudo que os componentes do treinamento didático e clínico sobre reparo de resina composta devem ser seriamente incluídos no currículo de ensino de instituições odontológicas, pois é do interesse do paciente. Os estudantes de odontologia devem receber treinamento clínico sobre este tópico para que possam seguir os protocolos de tomada de decisão adequados disponíveis durante o reparo ou substituição de restaurações de resina composta com defeito. Outras pesquisas no futuro podem ser realizadas para refinar as diretrizes e técnicas utilizadas para reparo de resina (AU)