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Abstract Among various natural hazards, those induced by hydrological and meteorological factors have emerged as the most frequent and damaging. India is at the second from the top, after Bangladesh, of flood hazard-affected countries of the world, causing immense damage to life and property every year. The Middle Ganga Plain in the country is one of the most severely affected regions due to the convergence of Himalayan rivers in the Ganga (Ganges) plain. This study focuses on optimizing novel ensemble models to enhance the mapping of flood hazard susceptibility in specific topoclimatic setting, characterized by a low-altitude-range, sub-tropical monsoonal climate, and a riverine floodplain environment of the tectonically active Middle Ganga Plain. This region forms part of the Ganga Foreland Basin prone to frequent floods. We employ a comprehensive flood inventory and twelve selected flood conditioning factors and is the first study that has developed these ensemble models in low relief riverine floodplain environmental setting with high resolution geomorphology as one of the conditioning factors. Four artificial intelligence ensemble models were employed in this work: Logistic Regression-Evidential Belief Function (LR-EBF), Logistic Regression-Frequency Ratio (LR-FR), Multi-Layer Perceptron-Evidential Belief Function (MLP-EBF), and Multi-Layer Perceptron-Frequency Ratio (MLP-FR). Results showed that LR-based ensembles outperformed MLP-based ensembles in the studied topoclimatic setting, with LR-EBF model achieving 87.2% and 84.7% success and prediction rates respectively. Our results reveal consistent performance differences between LR-based ensembles with FR and EBF models across different environmental settings. MLP-based ensembles, particularly with Frequency Ratio, displayed more significant performance variations. The findings underscore the importance of considering specific topoclimatic and altitudinal range environments when applying flood hazard susceptibility models. Our study also provides valuable insights for planning and policymaking in flood management practices in similar topoclimatic settings worldwide.

Abstract Climate variability significantly affects rainfall, air temperature, relative humidity, and solar radiation. In subtropical regions like India, intense monsoon rainfall primarily causes floods. This study aims to analyze the climatic factors contributing to flood occurrence in the Middle Ganga Plain (MGP) by examining meteorological parameters through various analyses, including monthly and yearly trends, spatial variability, exceedance probability, historical highest intensity rainfall, and wind trajectory analysis. By establishing a strong link between climatic variables and flood events, this research provides valuable insights into the impact of climate variability on flood patterns in the MGP. Results indicate that monsoon rainfall peaks from July to October, correlating with major flood events. During these months, high relative humidity increases the likelihood of rainfall. Spatial analysis shows higher rainfall in the northern Middle Ganga Plain (MGP), which aligns with observed flood patterns. Trend detection tests reveal increasing annual rainfall and rising average temperatures. Geostatistical analysis identifies the western and eastern MGP as areas prone to extreme rainfall. Exceedance probability analysis confirms the occurrence of substantial monsoon rainfall events. Wind trajectory analysis uncovers seasonal shifts that lead to low-pressure systems and heavy monsoon rainfall. The study establishes a strong link between climatic variables and flood events in the MGP region.

Background: Acute coronary syndrome (ACS) refers to a group of clinical symptoms compatible with acute myocardial ischemia and includes unstable angina, non-ST segment elevation myocardial infarction and ST-segment elevation myocardial infarction. Aims and Objectives: To study the incidence of lipid profile abnormalities in young patients (age 40 years or below) with ACS with clinical and cardiovascular risk profile. Material and Methods: The study was conducted on 223 young patients of acute coronary syndrome with age 40 years or below. 89 young patients with acute coronary syndrome having lipid abnormalities were further followed up after 1 month. Results: Majority of patients (55.15%) in the study population belonged to 35–40 years age group. Mean age of study population was 35.65 + 4.62 years with 90.13% males and 9.86% females. Main presenting symptom was precordial chest pain in 93.72% patients. Smoking was the commonest risk factor in young adults (81.7%). Other risk factors like diabetes, hypertension, family history were less common in young adults. Drug addiction was also higher in younger population (16%). Majority of young adults with acute coronary syndrome had more than 1 (47.53%) risk factor. Majority of patients were in Killip class I (86.9%) and only few patients (13.1%) had Killip class II or above. ST elevation myocardial infarction was far more common than NTEMI/USA and was found in 164 (73.5%) patients. Most common type of infarction was anterior wall myocardial infarction (62.80%). Majority of young patients had negative TMT, so it suggests that ACS in younger population has lesser complications during presentation, hospital stay and on follow-up. Conclusion: ACS in young continues to increase in Indian subcontinent. Younger patient with an ACS have different clinical characteristics and a different prognosis than older patients. The extent of CAD and degree of myocardial necrosis has influence on presentation and subsequent MACE in ACS and in this study, it appears dyslipidemia do not play any significant role in influencing extent of CAD and has little effect on outcome whether during acute stage or on immediate follow-up after ACS.

Dens evaginatus (DE) is a developmental disturbance that clinically appears as an accessory occlusal tuberculated cusp composed of enamel and dentin, enclosing a thin pulp tissue. It mainly involves the mandibular premolars. These cusp-like protrusions are susceptible to wear and fractures with subsequent pulp exposure leading to pulpal necrosis. In most cases, DE is discovered due to periapical inflammation in the absence of obvious clinical presentation of caries, trauma, or other pathologies, thus making it a diagnostic challenge. A case of nonvital tooth with an obscured DE in an 18-year-old male is reported here with a review of literature.

This study has developed a new ensemble model and tested another ensemble model for flood susceptibility mapping in the Middle Ganga Plain (MGP). The results of these two models have been quantitatively compared for performance analysis in zoning flood susceptible areas of low altitudinal range, humid subtropical fluvial floodplain environment of the Middle Ganga Plain (MGP). This part of the MGP, which is in the central Ganga River Basin (GRB), is experiencing worse floods in the changing climatic scenario causing an increased level of loss of life and property. The MGP experiencing monsoonal subtropical humid climate, active tectonics induced ground subsidence, increasing population, and shifting landuse/landcover trends and pattern, is the best natural laboratory to test all the susceptibility prediction genre of models to achieve the choice of best performing model with the constant number of input parameters for this type of topoclimatic environmental setting. This will help in achieving the goal of model universality, i.e., finding out the best performing susceptibility prediction model for this type of topoclimatic setting with the similar number and type of input variables. Based on the highly accurate flood inventory and using 12 flood predictors (FPs) (selected using field experience of the study area and literature survey), two machine learning (ML) ensemble models developed by bagging frequency ratio (FR) and evidential belief function (EBF) with classification and regression tree (CART), CART-FR and CART-EBF, were applied for flood susceptibility zonation mapping. Flood and non-flood points randomly generated using flood inventory have been apportioned in 70:30 ratio for training and validation of the ensembles. Based on the evaluation performance using threshold-independent evaluation statistic, area under receiver operating characteristic (AUROC) curve, 14 threshold-dependent evaluation metrices, and seed cell area index (SCAI) meant for assessing different aspects of ensembles, the study suggests that CART-EBF (AUCSR = 0.843; AUCPR = 0.819) was a better performant than CART-FR (AUCSR = 0.828; AUCPR = 0.802). The variability in performances of these novel-advanced ensembles and their comparison with results of other published models espouse the need of testing these as well as other genres of susceptibility models in other topoclimatic environments also. Results of this study are important for natural hazard managers and can be used to compute the damages through risk analysis.

Assessing the performance of land change simulation models is a critical step when predicting the future landscape scenario. The study was conducted in the district of Varanasi, Uttar Pradesh, India because the city being “the oldest living city in the world” attracts a vast population to reside here for short and long-term, leaving the city’s ecosystem more exposed to fragility and less resilient. In this work, an approach based on landscape metrics is introduced for comparing the performance of the ensemble models designed to simulate the landscape changes. A set of landscape metrics were applied in this study that offered comprehensive information on the performance of scenario-based simulation models from the viewpoint of the spatial ordering of simulated results against the related reference maps. A supervised support vector machine classification technique was applied to derive the LULC maps using Landsat satellite images of the year 1988, 2001, and 2015. The LULC maps of 1988 and 2001 were used to simulate the LULC scenario for 2015 using three Markov chain-based simulation models namely, multi-layer perceptron-Markov chain (MLP_Markov), cellular automata-Markov chain (CA_Markov), and stochastic-Markov chain (ST_Markov) respectively. The mean relative error (MRE), as a measure of the success of simulation models, was calculated for metrics. The MRE values at both the class and landscape levels were accounted for 21.63 and 11.45% respectively using MLP_Markov simulation model. The MRE values at both the class and landscape levels were accounted for 39.61 and 28.31% respectively using CA_Markov simulation model. The MRE values at both the class and landscape levels were accounted for 55.36 and 45.75% respectively using ST_Markov simulation model. The MRE values considered at class and landscape levels are further evaluated qualitatively for comparing the performance of simulation models. The results indicate that the MLP_Markov performed excellently, followed by CA_Markov and ST_Markov simulation models. This work showed an ordered and multi-level spatial evaluation of the models’ performance into the decision-making process of selecting the optimum approach among them. Landscape metrics as a vital characteristic of the utilized method, employ the maximum potential of the reference and simulated layers for a performance evaluation process. It extends the insight into the main strengths and drawbacks of a specific model when simulating the spatio-temporal pattern. The quantified information of transition among landscape categories also provides land policy managers a better perception to build a sustainable city master plan.

Aim: The purpose of this study was to evaluate the accuracy of implant casts generated with splinted and nonsplinted impression techniques with multiple parallel and nonparallel implants. Materials and Methods: In this experimental study, two edentulous maxillary stainless steel models with seven implant analogs in the central incisor, canine, premolar, and first molar region simulating clinical condition were used (control groups). In one master model, implant analogs were placed parallel to each other, whereas in another model, analogs were placed with a tilt-to-longitudinal axis. Forty stone casts were made from each model using splined and nonsplinted technique using polyether with open-tray technique. Then, the difference in the distance between the master cast and experimental cast in three dimensions was measured by coordinate-measuring machine. One-way ANOVA, post hoc Bonferroni test, and unpaired t-test were used for data analysis. Results: Statistical comparisons were made using ANOVA test, post hoc test, and unpaired t-test. Splinted technique with parallel implants generated interimplant distance values closest to the master model, followed by nonsplinted technique with parallel implants, splinted technique with angulated implants, and nonsplinted technique with angulated implants. Conclusions: Splinted impression technique exhibited higher accuracy than the other technique studies in both parallel and angulated implants.

Aim: This study aims to evaluate and compare the shear bond strength (SBS) of three different resin cements - total etch and rinse, self-etch and self-adhesive resin cements, used to bond the lithium disilicate restorations to human dentin. Settings and Design: Comparative -Invitro study design. Materials and Methods: Forty-five lithium disilicate (IPS E.max) discs (4 mm in diameter and 3 mm thick) were fabricated and randomly divided into three groups (n = 15). The occlusal surfaces of 45 extracted human maxillary premolars were ground flat. Fifteen specimens were luted, under a constant load, with each of the following resin cement: Variolink N (Group VN), Multilink N (Group MN), and Multilink Speed (Group MS). All cemented specimens were stored in distilled water for 1-week following which, they were tested under shear loading at a constant crosshead speed of 1 mm/min until fracture on a universal testing machine; the load at fracture was reported in megapascals (MPa) as the bond strength. Fractured specimens were also inspected by the scanning electron microscopy. Statistical analysis of the collected data was performed using one-way ANOVA test, post hoc Bonferroni test, and Chi-square test (α =0.05). Statistical Analysis Used: Oneway ANOVA test and post hoc Bonferroni test. Results: Mean SBS data of the groups in MPa were: Variolink N (Group VN): 14.19 ± 0.76; Multilink N (Group MN): 10.702 ± 0.75; and Multilink Speed (Group MS): 5.462 ± 0.66. Significant differences in SBS (P < 0.001) of the three resin cement were found. Intergroup comparison revealed statistically significant differences in SBS between Groups VN and MN (P < 0.001), Groups B and C (P < 0.001), and Groups VN and MS (P < 0.001). Chi-square test used to compare the distribution of mode of bond failure among the three groups delineated that the cohesive failure was significantly more among Group VN, whereas adhesive failure was significantly more among Group MN and MS. Conclusion: Total etch and rinse resin cement, i.e., Variolink N (Group VN) produced significantly higher bond strength of all-ceramics to dentin surfaces than did the self-etch and self-adhesive resin cements, i.e., Multilink N and Multilink Speed, respectively.

Abstract Floods are one of the most destructive natural disasters causing financial damages and casualties every year worldwide. Recently, the combination of data‐driven techniques with remote sensing (RS) and geographical information systems (GIS) has been widely used by researchers for flood susceptibility mapping. This study presents a novel hybrid model combining the multilayer perceptron (MLP) and autoencoder models to produce the susceptibility maps for two study areas located in Iran and India. For two cases, nine, and twelve factors were considered as the predictor variables for flood susceptibility mapping, respectively. The prediction capability of the proposed hybrid model was compared with that of the traditional MLP model through the area under the receiver operating characteristic (AUROC) criterion. The AUROC curve for the MLP and autoencoder‐MLP models were, respectively, 75 and 90, 74 and 93% in the training phase and 60 and 91, 81 and 97% in the testing phase, for Iran and India cases, respectively. The results suggested that the hybrid autoencoder‐MLP model outperformed the MLP model and, therefore, can be used as a powerful model in other studies for flood susceptibility mapping.

Category: Trauma; Ankle Introduction/Purpose: Intramedullary fixation of the distal fibula in unstable ankle fractures provides an alternative treatment strategy to traditional techniques and may reduce the complication profile. While often reserved for soft-tissue protection or elderly patients, the indications for this technique continue to expand. The purpose of this study was to evaluate the radiographic outcomes of ankle fractures treated with intramedullary fixation of the distal fibula with screw or flexible fixation of the syndesmosis. Methods: A retrospective case-series was performed of patients >18 years old with unstable ankle fractures treated at a single institution. Patients were treated with intramedullary fixation of the distal fibula and screw or suture-button fixation of the syndesmosis if indicated. Radiographic parameters measured included the medial clear space, tibiofibular overlap, tibiofibular clear space, talocrural angle, and fracture displacement. Fracture pattern, comorbidities, and postoperative complications were also assessed. Results: Fourteen patients (6 males, 8 females) with torsional ankle fractures (71% SER-IV patterns) were included in the study with a mean follow-up period of 5 months. Five patients had suture-button fixation and one patient had trans-syndesmotic screw fixation of the syndesmosis. All patients had improvement in radiographic parameters following surgical stabilization. Medial clear space decreased from a mean of 5.6 +- 3.1mm to 2.8 +- 0.79mm (p

Abstract Evapotranspiration and water availability are driven by changing climate and land cover parameters. In the present study, climatological records and land cover data were analysed simultaneously to accomplish the spatial distributions of climate change effects on water resources in Varanasi district, north India. Humidity–aridity was assessed by Lang's rain factor and De Martonne's aridity index, based on mean monthly rainfall and air temperature from seven meteorological stations. The climate change effect on water resources was evaluated using a 5 × 5 matrix that includes water availability and the aridity index by considering two time periods: 1941–1970 (1950s) and 1971–2000 (1980s). The methodology is based on seasonal crop evapotranspiration (ETc) (initial, mid‐season, end season and cold season) and annual water availability calculations. The high values (≤ 1,045 mm) of ETc were identified during the mid‐season stage. Water availability indicates decreases in the maximums from 718 to 636 mm during the two analysed periods, with a negative impact at the spatial scale. Lang's rain factor ( 40) in the south. De Martonne's aridity index indicates rapid aridization from south to north (28.3 in the 1950s and 25.6 in the 1980s). The high and very high climate effects on water resources in Varanasi district were found mainly in the crop lands, while in the urban areas the climate effect is low. The much affected area by climate change and land cover was depicted during the recent period (1980s). This statement was proved also by the Mann and Kendall test, which indicates a negative trend for annual precipitation at all stations (for the period 1941–2000), while the mean annual temperature had a positive trend for four stations. These findings suggest that climate change had a negative effect on water resources during the last 60 years in the study area.

Aim: The purpose of this study was to compare the marginal and internal adaptation of cobalt-chromium (Co-Cr) copings fabricated from conventional wax pattern, three-dimensional (3D)-printed resin pattern, and laser sintering technique. Materials and Methods: A total of thirty copings were made, out of which ten copings were made from 3D-printed resin pattern (Group A), ten from inlay wax pattern (Group B), and ten copings were obtained from direct metal laser sintering (DMLS) technique (Group C). All the thirty samples were seated on their respective dies and sectioned carefully using a laser jet cutter and were evaluated for marginal and internal gaps at the predetermined areas using a stereomicroscope. The values were then analyzed using one-way ANOVA test and post hoc Bonferroni test. Results: One-way ANOVA showed lowest mean marginal discrepancy for DMLS and highest value for copings fabricated from inlay wax. The values for internal discrepancy were highest for DMLS (169.38) and lowest for 3D-printed resin pattern fabricated copings (133.87). Post hoc Bonferroni test for both marginal and internal discrepancies showed nonsignificant difference when Group A was compared to Group B (P > 0.05) and significant when Group A was compared with Group C (P < 0.05). Group B showed significant difference (P < 0.05) when compared with Group C. Conclusion: Marginal and internal discrepancies of all the three casting techniques were within clinically acceptable values. Marginal fit of DMLS was superior as compared to other two techniques, whereas when internal fit was evaluated, conventional technique showed the best internal fit.

Purpose: The purpose of this study was to evaluate the effect of incisal butt joint and incisal overlap design on the fracture resistance of ceramic veneers under two different loading conditions, i.e., 125° and 60° representing protrusive and intercuspal movements, respectively. Materials and Methods: Thirty-two maxillary central incisors were divided into two groups of sixteen specimens each and were prepared with incisal butt joint and incisal overlap design. Ceramic veneers were fabricated and cemented. Both the groups were further divided and mechanical testing to evaluate the fracture resistance were done using the universal testing machine. The values were recorded in Newton along with the assessment of the failure mode of both veneer and the tooth. Results: Unpaired t-test showed a significant difference (P < 0.05) with butt joint design having higher fracture resistance than palatal overlap design with the mean value of 409.50N at 60° angle and 473.37N at 125° angle. Paired t-test depicted a significant difference for both the designs at 125° than at 60° angle (P < 0.05). Chi-square analysis showed more number of intact veneers with butt joint design; however, there was no significant difference (P > 0.05). Failure mode of teeth showed more number of coronal fracture followed by cervical fracture and root fracture, but there was no significant difference between the two groups (P > 0.05). Conclusion: Butt joint design had higher fracture resistance than palatal overlap design. Under functional loads for both designs, fracture resistance was higher at 125° than at 60° angle.

Aim: This study aims to evaluate the flexural strength, hardness, and impact strength of heat-cured high-impact denture base resins with different polymer/monomer ratios. Materials and Methods: A total of 150 acrylic samples were prepared using high impact denture base resin (Travelon Hi). The samples were divided into five groups based on different powder/liquid ratios (g/ml) with 30 samples in each group. The P/L ratio in Group 1 (Ratio - 2.2:1) was the manufacturer's recommended ratio and was used as control. In Group 2, the ratio was 2.7:1, in Group 3, the ratio was 3.2:1, in Group 4, the ratio was 1.9:1, and Group 5 the ratio was 1.6:1. Each group with 30 samples was further subdivided into three different subgroups comprising 10 samples each, based on the properties to be evaluated, i.e., for flexural strength, hardness, and impact strength evaluation. The samples were tested for flexural strength, Vicker's hardness number (VHN) and impact strength. One-way ANOVA including post hoc-Tukey's tests was used to calculate the difference of means for quantitative variables and for intergroup comparison as well. Results: The results showed that the flexural strength values and VHN values showed a similar trend. The values decreased significantly as the ratio was increased or decreased from the control group. The results also showed that there was nonsignificant difference between the mean impact strength values for all the groups. Conclusion: For reinforced resins or high impact resins, the manufacturer's recommended polymer/monomer mixing ratio should be used to obtain the appropriate strength of the material.

Recurrent floods are one of the major global threats among people, particularly in developing countries like India, as this nation has a tropical monsoon type of climate. Therefore, flood susceptibility (FS) mapping is indeed necessary to overcome this type of natural hazard phenomena. With this in mind, we evaluated the prediction performance of FS mapping in the Koiya River basin, Eastern India. The present research work was done through preparation of a sophisticated flood inventory map; eight flood conditioning variables were selected based on the topography and hydro-climatological condition, and by applying the novel ensemble approach of hyperpipes (HP) and support vector regression (SVR) machine learning (ML) algorithms. The ensemble approach of HP-SVR was also compared with the stand-alone ML algorithms of HP and SVR. In relative importance of variables, distance to river was the most dominant factor for flood occurrences followed by rainfall, land use land cover (LULC), and normalized difference vegetation index (NDVI). The validation and accuracy assessment of FS maps was done through five popular statistical methods. The result of accuracy evaluation showed that the ensemble approach is the most optimal model (AUC = 0.915, sensitivity = 0.932, specificity = 0.902, accuracy = 0.928 and Kappa = 0.835) in FS assessment, followed by HP (AUC = 0.885) and SVR (AUC = 0.871).

There is an evident increase in the importance that remote sensing sensors play in the monitoring and evaluation of natural hazards susceptibility and risk. The present study aims to assess the flash-flood potential values, in a small catchment from Romania, using information provided remote sensing sensors and Geographic Informational Systems (GIS) databases which were involved as input data into a number of four ensemble models. In a first phase, with the help of high-resolution satellite images from the Google Earth application, 481 points affected by torrential processes were acquired, another 481 points being randomly positioned in areas without torrential processes. Seventy percent of the dataset was kept as training data, while the other 30% was assigned to validating sample. Further, in order to train the machine learning models, information regarding the 10 flash-flood predictors was extracted in the training sample locations. Finally, the following four ensembles were used to calculate the Flash-Flood Potential Index across the Bâsca Chiojdului river basin: Deep Learning Neural Network–Frequency Ratio (DLNN-FR), Deep Learning Neural Network–Weights of Evidence (DLNN-WOE), Alternating Decision Trees–Frequency Ratio (ADT-FR) and Alternating Decision Trees–Weights of Evidence (ADT-WOE). The model’s performances were assessed using several statistical metrics. Thus, in terms of Sensitivity, the highest value of 0.985 was achieved by the DLNN-FR model, meanwhile the lowest one (0.866) was assigned to ADT-FR ensemble. Moreover, the specificity analysis shows that the highest value (0.991) was attributed to DLNN-WOE algorithm, while the lowest value (0.892) was achieved by ADT-FR. During the training procedure, the models achieved overall accuracies between 0.878 (ADT-FR) and 0.985 (DLNN-WOE). K-index shows again that the most performant model was DLNN-WOE (0.97). The Flash-Flood Potential Index (FFPI) values revealed that the surfaces with high and very high flash-flood susceptibility cover between 46.57% (DLNN-FR) and 59.38% (ADT-FR) of the study zone. The use of the Receiver Operating Characteristic (ROC) curve for results validation highlights the fact that FFPIDLNN-WOE is characterized by the most precise results with an Area Under Curve of 0.96.

The use of implants in the oral and maxillofacial skeleton continues to expand and since then implant surfaces have been modified in various ways to improve biocompatibility and accelerate osseointegration, which results in a shorter edentulous period for a patient. This article reviewed several methods that are widely used to modify the topography or chemistry of titanium surface, including blasting, acid etching, anodic oxidation, fluoride treatment, and calcium phosphate coating. Such modified surfaces demonstrate faster and stronger osseointegration than the turned commercially pure titanium surface.

Background or Statement of Problem: As, the longevity of provisional restorations is related to, a perfect adaptation and a strong, long-term union between restoration and teeth structures, therefore, evaluation of marginal leakage of provisional restorative materials luted with cements using the standardized procedures is essential. Aims and Objectives: To compare the marginal leakage of the provisional crowns fabricated from Autopolymerizing acrylic resin crowns and bisphenol A-glycidyl dimethacrylate (BIS-GMA) resin crowns. To compare the marginal leakage of the provisional crowns fabricated from autopolymerizing acrylic resin crowns and BIS-GMA resin crowns cemented with different temporary luting cements. To compare the marginal leakage of the provisional crowns fabricated from autopolymerizing acrylic resin (SC-10) crowns cemented with different temporary luting cements. To compare the marginal leakage of the provisional crowns fabricated from BIS-GMA resin crowns (Protemp 4) cemented with different temporary luting cements. Methodology: Freshly extracted 60 maxillary premolars of approximately similar dimensions were mounted in dental plaster. Tooth reduction with shoulder margin was planned to use a customized handpiece-holding jig. Provisional crowns were prepared using the wax pattern fabricated from computer aided designing/computer aided manufacturing milling machine following the tooth preparation. Sixty provisional crowns were made, thirty each of SC-10 and Protemp 4 and were then cemented with three different luting cements. Specimens were thermocycled, submerged in a 2% methylene blue solution, then sectioned and observed under a stereomicroscope for the evaluation of marginal microleakage. A five-level scale was used to score dye penetration in the tooth/cement interface and the results of this study was analyzed using the Chi-square test, Mann–Whitney U-test, Kruskal–Wallis H-test and the results were statistically significant P < 0.05 the power of study - 80%. Results: Marginal leakage was significant in both provisional crowns cemented with three different luting cements along the axial walls of teeth (P < 0.05) confidence interval - 95%. Conclusion: The temporary cements with eugenol showed more microleakage than those without eugenol. SC-10 crowns showed more microleakage compared to Protemp 4 crowns. SC-10 crowns cemented with Kalzinol showed maximum microleakage and Protemp 4 crowns cemented with HY bond showed least microleakage.

Background: Fewer studies were conducted on resistance form. This study evaluated the effect of different auxiliary features on inadequate resistance form. Aim: The aim of the study is to evaluate the resistance at 22° taper with reduced occluso-cervical height with different auxiliary features. Methodology: An ivorine tooth was prepared with computer-aided design-computer-aided manufacturing with total occlusal convergence (TOC) of 22°, shoulder finish line 0.9 mm wide, reduced occluso-cervical height, i.e., 2.5 mm, and reduced diameter. The crown preparation was subsequently modified to include interproximal grooves, interproximal boxes, and reduced TOC in the axial wall from 22° to 8° in the cervical 1.5 mm of the axial wall. A total of four groups with ten standardized metal dies were prepared for each design with the computer-aided milling machine. Standardized complete metal crowns using silicon mold were fabricated and cemented on metal dies with glass ionomer cement. The resistance of each specimen was evaluated when force was applied at a 45° angulation to the long axis of the die in a lingual to buccal direction by a universal testing machine. The values were then analyzed using one-way analysis of variance test and post hoc Bonferroni test. Results: The comparison of the mean resistance test values was done among all the groups, and there was a significant (P ≤ 0.001) difference found among the groups. Conclusion: The most effective method of enhancing resistance form preparation is to decrease the TOC of the cervical portion of the prepared axial walls. Two interproximal boxes significantly increased the resistance form. However, two interproximal grooves did not significantly increase the resistance form.

The success of the prosthetic rehabilitation in a long-span fixed partial denture (FPD) requires adequate restoration of its function, periodontal health, and esthetics. This case report describes various treatment options to overcome stresses produced in a long-span FPD with tilted molar.

Amelogenesis imperfecta has been described as a group of hereditary enamel defects not associated with systemic diseases. Restoration of these defects is important not only because of esthetic and functional concern, but also because there may be a positive psychological impact on the patient. Among various treatments described for rehabilitation of amelogenesis imperfecta, this case report described the rehabilitation of patient utilizing twin stage procedure with aim of improving patient′s function, appearance, restoring the proper contacts, and simplifying the prosthetic clinical and lab work procedures. Twin stage procedure is based on the fact that prevents horizontal forces acting during various mandibular excursion in full mouth rehabilitation case, to control horizontal forces which in turn depends upon the condylar path, incisal path, and cusp angle. Among them, role of cusp angle is more supported whereas condylar path and incisal path role is considered unreliable.

Herpes zoster (HZ) infection of the maxillary and mandibular divisions of the trigeminal nerve manifests orally as unilateral vesicular eruption localized to the skin and mucus membrane of the dermatome innervated by the trigeminal nerve. Herpes zoster infection has been observed in immunocompromised states like uncontrolled diabetes, cancer chemotherapy, lymphoproliferative diseases, and recently in HIV-positive patients. There are only a few case reports of osteonecrosis due to HZ in an HIV-positive patient in an Indian population, this being the first in a North Indian population. We propose that osteonecrosis should be considered as a strong indicator of HIV infection, especially in a developing country like India. The present case highlights the complexities which can arise in an HIV-inflicted individual suffering from HZ infection. Early diagnosis of such infections can lead to effective treatment and prevention of complications.

Purpose: This study was aimed to determine the effect of various tray spacer thickness and subsequent repeated pours on the accuracy and dimensional stability of the impression made from monophasic polyvinyl siloxane material. Materials and Methods: Custom trays with different spacer thickness (2, 4 and 6 mm) were used for making an impression of a master model simulating 3 unit fixed partial denture with monophasic polyvinyl siloxane material. These impressions were poured with die stone and repoured. Distance between the reference points were measured and subjected to statistical analysis. Result: Casts obtained from 1 st , 2 nd and 3 rd pour of the impression in 2, 4 and 6 mm spacer thickness tray have similar dimensional accuracy amongst each other and with the master model except in molar diameter and inter-abutment distances of cast obtained from 6 mm spacer thickness tray. Conclusion: The vertical distance of stone dies were decreased, whereas horizontal distance increased as the thickness of impression material is increased. There were statistically non-significant changes occurring among the repeated pours in 2, 4 and 6 mm spacer thickness. Clinical Implication: 2 and 4 mm spacer thickness are acceptable for making an impression for three unit fixed partial denture with monophasic polyvinyl siloxane material and it was not affected by two subsequent (1 st and 2 nd ) repeated pours.

Introduction: To overcome limitations of screw-retained prostheses, cement-retained prostheses have become the restoration of choice now a days. Selection of the cement hence becomes very critical to maintain retrievability of the prostheses. Aim: The purpose of this study was to assess and compare the retention of base metal crowns cemented to implant abutments with five different luting cements. Materials and Methods: Ten implant analogs were secured in five epoxy resin casts perpendicular to the plane of cast in right first molar and left first molar region and implant abutments were screwed. Total of 100 metal copings were fabricated and cemented. The cements used were zinc phosphate, resin modified glass ionomer cement, resin cement, non-eugenol acrylic based temporary implant cement & non-eugenol temporary resin cement implant cement. Samples were subjected to a pull-out test using an Instron universal testing machine at a crosshead speed of 0.5mm/min. The load required to de-cement each coping was recorded and mean values for each group calculated and put to statistical analysis. Results: The results showed that resin cement has the highest retention value 581.075N followed by zinc phosphate luting cement 529.48N, resin modified glass ionomer cement 338.095 N, non-eugenol acrylic based temporary implant cement 249.045 N and non-eugenol temporary resin implant cement 140.49N. Conclusion: Within the limitations of study, it was concluded that non-eugenol acrylic based temporary implant cement and non-eugenol temporary resin implant cement allow for easy retrievability of the prosthesis in case of any failure in future. These are suitable for cement retained implant restorations. The results provide a possible preliminary ranking of luting agents based on their ability to retain an implant-supported prosthesis and facilitate easy retrieval.

Acrylic resin denture teeth often exhibit rapid occlusal wear, which may lead to decrease in the chewing efficiency, loss of vertical dimension of occlusion, denture instability, temporomandibular joint disturbances, etc. There are various treatment options available like, use of highly cross linked acrylic teeth, amalgam or metal inserts on occlusal surface, use of composite, gold or metal occlusal surface, etc. Several articles have described methods to construct gold and metal occlusal surfaces, however, these methods are time-consuming, expensive and requires many cumbersome steps. These methods also requires the patient to be without the prosthesis for the time during which the laboratory procedures are performed. This article presents a quick, simple and relatively inexpensive procedure for construction of metal occlusal surfaces on complete dentures.

Context: Most of the maxillary complete dentures do not adapt accurately to the cast because of the changes in the resin during polymerization. The amount of heat associated with processing of polymethyl methacrylate has been correlated with the adaptation of the processed denture base to its supporting tissues. Aims: This study conducted to determine the effect of different curing temperatures on the accuracy of fit of a complete maxillary denture and to compare with that of fiber-reinforced acrylic resins. Materials and Methods : An ideal maxillary rubber mould used to make an edentulous cast. Forty-eight stone casts made from the ideal rubber mould. Out of 48 identical stone casts, 44 stone casts with wax adapted processed using simple acrylic resin. The remaining four stone casts were processed using fiber-reinforced acrylic resin. However, processing time for 12 hrs was maintained constant for all the samples. The variable to investigate was the temperature. Therefore, four denture bases processed at each temperature from 60°C to 80°C with two-degree increments for a total of 44 samples using simple acrylic resin. Remaining four samples processed at 70°C using fiber-reinforced acrylic resin. A traveling microscope used to measure the discrepancy between each cast and its denture base. Statistical analysis used: Analyzed with Student′s unpaired t test. Results : Minimum distortion was observed at 70°C. Maximum distortion was observed for the denture bases processed at 80°C. Amount of distortion increases as the processing temperature increases which was highly significant. Distortion was significantly high from 60 to 68°C in the decreasing order. Conclusion: This study verified the observation that maxillary complete denture base show the greatest discrepancy at the central portion of the posterior palatal seal region as the processing temperature increases.

The branch of Prosthodontics is not only a science but also an art of handling patients who present with limitations in continuing with normal procedures. An abnormally small mouth opening is called as microstomia. The common reasons for this condition include scleroderma, orofacial malignancies, surgery, burns and TMJ ankylosis. Impressions can be made for patients with restricted mouth opening with a sectional impression tray that can be assembled and disassembled in the mouth and reassembled outside the mouth. This article describes a sectional tray system for making preliminary and secondary impressions. Also an innovative technique of fabricating a sectional complete denture for a microstomic patient has been described.

Microstomia may result from surgical treatment of orofacial neoplasms, cleft lips, maxillofacial trauma, burns, radiotherapy or scleroderma. A maximal oral opening that is smaller than the size of a complete denture can make prosthetic treatment challenging. This clinical report presents the prosthodontic management of a total edentulous patient with microstomia. Sectional mandibular and maxillary trays and foldable mandibular and maxillary denture were fabricated for the total edentulous patient.

Microstomia may result from surgical treatment of orofacial neoplasms, cleft lips, maxillofacial trauma, burns, radiotherapy, or scleroderma. A maximal oral opening that is smaller than the size of a complete denture can make prosthetic treatment challenging. This clinical paper presents the prosthodontic management of a total edentulous patient with microstomia. Sectional mandibular and maxillary trays and foldable mandibular and maxillary denture were fabricated for the total edentulous patient.