Success of fixed partial denture prostheses observed in a military dental centre: A cross-sectional study.

Background: Fixed dental prostheses have been provided in the Armed Forces for a long time, yet definite evidence-based guidelines on the success and failure of different types of prostheses are currently lacking. A cross-sectional observational study was conducted as a step towards addressing this lacuna. Methods: The study included 156 patients and 538 prostheses based on pre-established inclusion criteria. The types of prostheses that were evaluated included crowns, fixed partial dentures (FPDs), post and core restorations, dental implants and veneers. Visual, tactile and radiographic examination was used for evaluating the prostheses. Success, survival and failure of prostheses were evaluated, and the types of complications leading to the failure were also recorded. In addition, the oral hygiene status of the included patients was also evaluated using the Oral Hygiene Index-Simplified. Results: The overall failure rate in all prostheses combined together was 28.81%. The failure rate in cantilever FPDs was the highest at 44.44%. It was 16.67% in veneers, 35.37% in conventional FPDs, 23.81% in single crowns and 30.56% in all post and core restorations. Conclusion: Barring the all-ceramic prostheses and fibre post and core restorations, the rate of occurrence of both complications and failures in the remaining categories of prostheses was higher than that mentioned in the literature.

Comparative evaluation of the tensile bond strength of two silicone based denture liners with denture base resins.

BACKGROUND: To evaluate and compare tensile bond strength of two silicone based liners with heat cure and heat cure high impact denture base resin at baseline and after storage in artificial saliva for 30 and 60 days. METHOD: Heat cure conventional and high impact acrylic blocks (120 blocks each) prepared with final test specimen of two blocks of each resin with a liner. The baseline samples and those tested after 30 and 60 days interval stored in artificial saliva in thermal incubator, all were pulled apart in UTM at 20 mm/min. The tensile bond strength and mode of failure (adhesive/cohesive) were assessed. Mean, SD determined and analysis using one way ANOVA and paired 't' test. RESULTS: The highest mean tensile bond strength (1.028 MPa) and the least i.e. 0.289 MPa was observed with Permaflex silicone liner against heat cure PMMA after storage in artificial saliva at 37 ± 1 °C. CONCLUSION: The study rejected the null hypothesis because storage time in artificial saliva affected the bond strength of the resilient liners examined. The results revealed a statistically significant difference (p < 0.05) of artificial saliva storage on the bond strength of both the liners. After storage in artificial saliva for 30 days and 60 days at 37 ± 1 °C, all the specimens showed a significant reduction in the tensile bond strength.

Determination of mesiodistal width of maxillary anterior teeth using inner canthal distance.

BACKGROUND: Selection of appropriately sized maxillary anterior teeth is one of the important aspects of complete denture prosthodontics. In the past several methods have been proposed, but little consensus on an effective method for anterior teeth selection has been reached. Inner canthal distance is one of the reliable anatomic dimension that may provide a valid approach to anterior teeth selection. This study was aimed to ascertain the co-relation between inner canthal distance (ICD) and combined mesiodistal width of maxillary anterior teeth. METHOD: This study was conducted in Army Dental Centre (R & R) Delhi Cantonment between Aug 2006 to Mar 2008. Eight hundred dentate Indian subjects of four different ethnic group; Such as Rajputs, Marathas, Sikh and Tamilian. 100 males and 100 females from each race under the age group of 18-30 years formed the subjects of study. The ICD and mesio-distal width of maxillary anteriors were measured using Digital Vernier Caliper. The Data obtained was statistically analyzed. RESULTS: A consistent ratio of 1.61 was found between ICD and combined mesiodistal width of maxillary anteriors in all four ethnic group. The mean value showed no statistically significant difference between sex. The variation in the ratio between the ethnic groups was negligible. CONCLUSION: The findings of the study indicated that, to select the combined mesiodistal width of maxillary anterior teeth, ICD of the required patient should be multiplied by 1.61. This ratio was consistent with all the four ethnic groups irrespective of sex.

Haematological alterations induced by oral subacute exposure to fenvalerate, nitrate and their combination in domestic buffalo, Bubalus bubalis.

The present study investigated haematological alterations induced by oral subacute exposure to fenvalerate, nitrate and their combination in the domestic buffalo, Bubalus bubalis. Fenvalerate exposure produced significant declines in haemoglobin (Hb), total leukocyte count (TLC), total erythrocyte count (TEC) and mean corpuscular haemoglobin concentration (MCHC), and a corresponding elevation in mean corpuscular volume (MCV). Following oral exposure to sodium nitrate, significant declines in blood Hb, TLC, TEC, MCH and MCHC, and a significant elevation in MCV occurred. Combined exposure to fenvalerate and sodium nitrate produced severe effects with an appreciably more prominent decline in Hb, TLC, TEC and MCHC and a significant elevation in MCV. The percentage of methaemoglobin was observed to follow an elevating trend in animals exposed to sodium nitrate alone (0.69 %-13.8 %) and in combination with fenvalerate (0.75 %-13.7 %).

Evaluation of shear bond strength of composite resin bonded to alloy treated with sandblasting and electrolytic etching.

Conservation of natural tooth structure precipitated the emergence of resin-retained fixed partial dentures. The weakest link in this modality is the bond between resin cement and alloy of the retainer. Various alloy surface treatment have been recommended to improve alloy-resin bond. This in vitro study was carried out to observe changes in the Nickel-Chromium alloy (Wiron 99, Bego) surface following sandblasting or electrolytic etching treatment by scanning electron microscope (SEM) and to evaluate the shear bond strength of a resin luting cement bonded to the surface treated alloy. 80 alloy blocks were cast and divided into four groups of 20 each. In groups-A & B, the test surfaces were treated by sandblasting with 50 and 250 µm sized aluminium oxide particles respectively. In groups-C & D, the test surfaces were first treated by sandblasting with 50 and 250 µm sized aluminium oxide particles respectively followed by electrolytic etching. Test surfaces were observed under SEM at 1,000× magnification. Two alloy blocks of each group were luted together by a resin luting cement (Rely X, 3M) and their shear bond strength was tested. The mean shear bond strength in MPa of groups-A to D were 6.44 (±0.74), 8.18 (±0.51), 14.45 (±0.59) and 17.43 (±1.20) respectively. Group-D showed bond strength that is more than clinically acceptable bond strength. It is recommended that before luting resin-retained fixed partial dentures, the fitting surface of the retainer should be electrolytically etched to achieve adequate micromechanical retention.

A Clinically Explainable AI-Based Grading System for Age-Related Macular Degeneration Using Optical Coherence Tomography.

We propose an automated, explainable artificial intelligence (xAI) system for age-related macular degeneration (AMD) diagnosis. Mimicking the physician's perceptions, the proposed xAI system is capable of deriving clinically meaningful features from optical coherence tomography (OCT) B-scan images to differentiate between a normal retina, different grades of AMD (early, intermediate, geographic atrophy (GA), inactive wet or active neovascular disease [exudative or wet AMD]), and non-AMD diseases. Particularly, we extract retinal OCT-based clinical imaging markers that are correlated with the progression of AMD, which include: (i) subretinal tissue, sub-retinal pigment epithelial tissue, intraretinal fluid, subretinal fluid, and choroidal hypertransmission detection using a DeepLabV3+ network; (ii) detection of merged retina layers using a novel convolutional neural network model; (iii) drusen detection based on 2D curvature analysis; (iv) estimation of retinal layers' thickness, and first-order and higher-order reflectivity features. Those clinical features are used to grade a retinal OCT in a hierarchical decision tree process. The first step looks for severe disruption of retinal layers' indicative of advanced AMD. These cases are analyzed further to diagnose GA, inactive wet AMD, active wet AMD, and non-AMD diseases. Less severe cases are analyzed using a different pipeline to identify OCT with AMD-specific pathology, which is graded as intermediate-stage or early-stage AMD. The remainder is classified as either being a normal retina or having other non-AMD pathology. The proposed system in the multi-way classification task, evaluated on 1285 OCT images, achieved 90.82% accuracy. These promising results demonstrated the capability to automatically distinguish between normal eyes and all AMD grades in addition to non-AMD diseases.

Oral pain and infection control strategies for treating children and adolescents in India.

INTRODUCTION: Oral and dental health form an integral part of complete well being of an individual and society at large. Promoting oral health and societal progression go hand in hand. AIM: To investigate dentists' attitudes about pain and infection control while treating children and adolescents by assessing their recommendations of pre- and postoperative analgesics and antibiotics, and use of local anesthesia (LA) for definitive treatment in different clinical scenarios. MATERIALS AND METHOD: A total of 400 dentists, both general dental practitioners (GDPS) as well as specialist dentists, were surveyed over a period of 2 months by using a pre-tested close-ended questionnaire. The data was statistically analyzed using Pearson's Chi-square test and backward logistic regression analysis for analysis of categorical variables and independent variables, respectively. Level of significance was set at 5%. RESULTS: It was found that there was a gross overuse of antibiotics and analgesics and under use of LA by GDPs compared to specialist dentists. Postoperative antibiotics and analgesics were used more commonly than preoperative antibiotics and analgesics. These strategies were used more often in permanent teeth than primary teeth except the use of LA, which was used with equal frequency in both primary as well as permanent dentition. CONCLUSION: Dependence on antibiotics and analgesics for achieving pain and infection control in children has to be minimized and focus has to be shifted on judicious definitive treatment involving use of LA, aseptic techniques, and behavior management techniques.

Precise higher-order reflectivity and morphology models for early diagnosis of diabetic retinopathy using OCT images.

This study proposes a novel computer assisted diagnostic (CAD) system for early diagnosis of diabetic retinopathy (DR) using optical coherence tomography (OCT) B-scans. The CAD system is based on fusing novel OCT markers that describe both the morphology/anatomy and the reflectivity of retinal layers to improve DR diagnosis. This system separates retinal layers automatically using a segmentation approach based on an adaptive appearance and their prior shape information. High-order morphological and novel reflectivity markers are extracted from individual segmented layers. Namely, the morphological markers are layer thickness and tortuosity while the reflectivity markers are the 1st-order reflectivity of the layer in addition to local and global high-order reflectivity based on Markov-Gibbs random field (MGRF) and gray-level co-occurrence matrix (GLCM), respectively. The extracted image-derived markers are represented using cumulative distribution function (CDF) descriptors. The constructed CDFs are then described using their statistical measures, i.e., the 10th through 90th percentiles with a 10% increment. For individual layer classification, each extracted descriptor of a given layer is fed to a support vector machine (SVM) classifier with a linear kernel. The results of the four classifiers are then fused using a backpropagation neural network (BNN) to diagnose each retinal layer. For global subject diagnosis, classification outputs (probabilities) of the twelve layers are fused using another BNN to make the final diagnosis of the B-scan. This system is validated and tested on 130 patients, with two scans for both eyes (i.e. 260 OCT images), with a balanced number of normal and DR subjects using different validation metrics: 2-folds, 4-folds, 10-folds, and leave-one-subject-out (LOSO) cross-validation approaches. The performance of the proposed system was evaluated using sensitivity, specificity, F1-score, and accuracy metrics. The system's performance after the fusion of these different markers showed better performance compared with individual markers and other machine learning fusion methods. Namely, it achieved [Formula: see text], [Formula: see text], [Formula: see text], and [Formula: see text], respectively, using the LOSO cross-validation technique. The reported results, based on the integration of morphology and reflectivity markers and by using state-of-the-art machine learning classifications, demonstrate the ability of the proposed system to diagnose the DR early.

Effect of Sugarcane Cultivar and Foliar Insecticide Treatment on Infestations of the Invasive Sugarcane Thrips, Fulmekiola serrata (Thysanoptera: Thripidae), in Florida.

Fulmekiola serrata (Kobus) was observed infesting sugarcane, Saccharum spp. hybrids, in the United States for the first time in January 2017 in Florida. Field studies were conducted to determine F. serrata infestation levels on popular sugarcane cultivars and to determine the efficacy of foliar insecticide treatments that could be used for management. Cultivar evaluations comparing six and five commercial cultivars representing >46% of the sugarcane production area in Florida were conducted in 2017 and 2018, respectively. Fulmekiola serrata infestation levels did not differ among cultivars in 2017. However, infestation levels on CP 00-1101 were greater than on CP 96-1252 grown on organic soils, and infestation levels on CP 96-1252 were greater than on CPCL 97-2730 grown on mineral soils in 2018. Three insecticide evaluations, two in 2017 and one in 2018, were conducted. The pyrethroid lambda-cyhalothrin, which is registered for use on sugarcane, was consistently associated with the greatest decreases in F. serrata infestation levels. The neonicotinoids imidacloprid and thiamethoxam, as well as the butenolide flupyradifurone, decreased infestation levels but to a lesser extent than did lambda-cyhalothrin. The spinosyn spinetoram was associated with the lowest decreases in F. serrata infestation levels. Our results supported short-term F. serrata management recommendations: Popular Florida sugarcane cultivars should be considered equally susceptible to F. serrata until additional evaluations are conducted and F. serrata outbreaks can be treated with lambda-cyhalothrin when infestations stress the crop beyond acceptable levels.

In vivo changes in antioxidant system and protective role of selenium in chlorpyrifos-induced subchronic toxicity in bubalus bubalis.

Chlorpyrifos, an organophosphate, is one of the widely used insecticides for control of pests in various agricultural and animal husbandry operations. The objective of the present investigation was to assess the effect of subchronic exposure of chlorpyrifos on the antioxidant status of buffalo calves and to perceive the role of selenium in cases of chlorpyrifos toxicity. Chlorpyrifos at a dose rate of 0.05mg/kg per day for 20 consecutive weeks, significantly elevated the enzymic activity of glutathione peroxidase (GPx) (54.8%), glutathione reductase (GR) (79.4%), glutathione-S-transferase (GST) (34.2%), glucose-6-phosphate dehydrogenase (G6PD) (33.2%), superoxide dismutase (SOD) (19.3%) and catalase (CAT) (63.8%). The altered antioxidant status was well evident from the depleting glutathione levels and a two-fold rise in the extent of lipid peroxidation. Supplementation of selenium in the form of sodium selenite @ 0.05mg/kg per day for 20 weeks in chlorpyrifos intoxicated calves had a marked beneficial effect on the overall antioxidant potential of the animals as evident by no significant alteration in the extent of lipid peroxidation, levels of blood glutathione and activities of various antioxidant enzymes viz. GST, GR, SOD, CAT and G6PD. There was only a significant increase in the activity of GPx to the tune of 27.4%. Therefore, on the basis of the present investigation it can be suggested that oxidative stress is one of the main mechanism involved in chlorpyrifos toxicity and supplementation with sodium selenite in such cases can have significant beneficial and therapeutic effects.

Plasma concentrations, pharmacokinetics and urinary excretion of gatifloxacin after single intravenous injection in buffalo calves.

The pharmacokinetics and urinary excretion of gatifloxacin were investigated after a single intravenous injection of 4 mg/kg body weight in buffalo calves. The therapeutic plasma drug concentration was maintained for up to 12 h. Gatifloxacin rapidly distributed from blood to tissue compartments, which was evident from the high values of the distribution rate constant, alpha1 (11.1 +/- 1.06 h(-1)) and the rate constant of transfer of drug from central to peripheral compartment, k12 (6.29 +/- 0.46 h(-1)). The area under the plasma drug concentration-time curve and apparent volume of distribution were 17.1 +/- 0.63 (microg.h)/ml and 3.56 +/- 0.95 L/kg, respectively. The elimination half-life (t (1/2 beta)), total body clearance (ClB) and the ratio of drug present in tissues and plasma (T/P) were 10.4 +/- 2.47 h, 235.1 +/- 8.47 ml/(kg.h) and 10.1 +/- 2.25, respectively. About 19.7% of the administered drug was excreted in urine within 24 h. A satisfactory intravenous dosage regimen for gatifloxacin in buffalo calves would be 5.3 mg/kg at 24 h intervals.

Evaluation of Four Elastomeric Interocclusal Recording Materials.

BACKGROUND: The fabrication of dental prosthesis requires the transfer of interocclusal records from patient's mouth to semi-adjustable articulators using different kinds of recording media. Any inaccuracy in these interocclusal records leads to occlusal errors in the final prosthesis. This study was conducted to evaluate the dimensional changes occurring in the interocclusal recording material over a given period of time and the material's resistance to compression during the cast mounting on the articulator. METHODS: In this in vitro study, the linear dimensional change and compressive resistance of four commercially available elastomeric interocclusal recording media was tested. Three were addition silicones and the fourth was a polyether material. Cylindrical samples of 10mm diameter of each material were prepared in three different thicknesses of 2, 4 and 6mm. Ten samples each of thickness of 2, 4 and 6mm for all four materials were prepared (total of 120 samples). The linear dimensional changes of the samples were evaluated after 24 hours of fabrication. The compressive resistance was measured when each of these was subjected to a constant compressive load of 25 Newtons. RESULTS: The mean linear dimensional change in a horizontal plane was minimum for Kanibite Hard, an addition silicone. Ramitec showed the maximum linear dimensional change. The mean compression distance was least for Futar D Occlusion (an addition silicone) and maximum for Ramitec (a polyether). It was observed that the samples of thickness 2mm for all the materials underwent least compression. CONCLUSION: The compressive resistance of each elastomer was inversely proportional to the thickness of the sample. This implies that minimum thickness of the recording materials should be used for recording maxillomandibular relations without sacrificing the strength of the interocclusal record.

Two Pelvic Digits on Same Side: Double Trouble?

Pelvic digit is a rare congenital anomaly of pelvis usually discovered incidentally on plain radiography. It usually develops in the soft tissue adjacent to the normal skeletal tissue. Its importance lays in its differentiation from heterotopic ossification, osteochondroma, Fong's disease and traumatic avulsion injuries of pelvis to avoid any unnecessary investigations and interventions. Here, we report a 32-year-old male presenting with complain of pain in right hip, was subjected to radiographic examination and two pelvic digits were noticed arising from the iliac bone in addition to features of osteoarthritis of hip joint. The symptomatology was attributed to osteoarthritis of hip after thorough physical examination and imaging investigations.

Changes in bone mineralization pattern: a response to local stimulus in maxilla and mandible of dogs.

A pilot study was carried out in order to verify the pattern of changes in mineralization of bone in the maxillas and mandibles of dogs which had a tooth extraction or luxation. Bone mineral content was determined using computerized microdensitometry. Significant changes in patterns of mineralization were found for alveolar bone, cortical bone and trabecular bone at the sites adjacent to the area of operation. These findings suggest that the three envelopes of jaw bones of the dogs are influenced by Regional activation phenomenon (RAP). These results have important implications for the design of clinical studies of periodontium. A more detailed study should elucidate the cellular mechanisms by which these changes occur.

Autoradiographic investigation of circadian rhythms in alveolar bone periosteum and cementum in young mice.

This report presents circadian rhythms in cell proliferation of alveolar bone periosteum and cementum of the maxillary first molars of male 5-week-old BNL, Swiss albino mice which were maintained on a 12 hr light/dark cycle. Mice were injected with 3H-TDR (luCi/gm. body wt.) 1 hr prior to sacrifice and killed every 3 hrs for 24 hrs starting at 9 a.m. Maxillae were decalcified, routinely processed histologically and autoradiographs prepared. Cell labeling indices of alveolar bone and cementum mesial to the first molar were determined. Alveolar bone periosteal and cemental cells show circadian rhythm in their DNA synthetic processes. Peaks in percent labeling exhibit higher values than previously reported for nontraumatized, normal dental periosteum and cementum. While the outer periosteum reveals a single 24 hr peak (6 p.m.), inner periosteum and cementum reveal two ultradian peaks 9 to 12 hrs apart involving both light and dark periods. Rodents are nocturnal, but high peaks are also evident in the light periods, consequently, not all peaks are synonymous with the period of animal activity and feeding. Although the single daylight peak of the outer periosteum may indicate growth of that surface at night to about noon, the double peaks exhibited by inner periosteum and cementum indicate light/dark, continuously active surfaces in terms of DNA synthesis and growth.

Proton spin-lattice relaxation time study in tissues of the adult newt Taricha granulosa (Amphibia: Urodele).

Nuclear magnetic resonance (NMR) pulse techniques were used to obtain values for the spin-lattice relaxation time (T1) of whole blood, plasma, blood cells, in vitro liver samples, and live and necrotic tail samples for adult Taricha granulosa. The T1 for whole blood is (0.80 +/- 0.01) s, for plasma (0.76 +/- 0.02) s and for blood cells (0.83 +/- 0.01) s, and did not change over several hours of measurement. The necrotic liver gave a single T1 of (0.28 +/- 0.02) s within the first 20 min of excision with a gradual increase over the next 3.5 h. Live and dead tail samples gave two T1 values: a short T1 of about 0.15 s remaining essentially constant and a long T1 starting at 0.68 s and increasing to 0.9 s during the 5 h of the experiment.

Psychosocial issues in chronic obstructive pulmonary disease.

Chronic illnesses such as COPD require both comprehensive evaluations and multisystem treatment approaches with integration of biological, behavioral, psychological, and social systems. People function as biopsychosocial units, with complex interplay between themselves and their environments determining the degree of their illness. Illness, as distinct from disease, is a person's subjective response to the state of disease or organ pathology. Recognition and identification of the psychosocial components of a person's illness allows for far more effective therapeutic intervention. Treatment objectives include better acceptance of life changes and the development of new attitudes and goals through an increase in self-confidence and control over emotional, physical, and respiratory functioning. These rehabilitation goals can be fulfilled by the use of supportive therapies (individual, family, or marital and group) and educational behavioral techniques based upon a solid working alliance with the patient.

Toxicological effects of monocrotophos on microorganisms in the rumen of Bubalus bubalis.

Repeated oral administration of monocrotophos in doses of 0.5 and 2.0 mg.kg-1.d-1 produced a significant reduction in the total number of protozoa (31-40%) in the rumen of buffalo calves. However, the insecticide has no appreciable effect on the total bacterial count. Rumen pH declined significantly with both doses of insecticide. In the differential protozoal count, different doses of monocrotophos caused an increase in the percentage of Dasytrichia, Epidinium and other protozoa; however, the percentage of Isotrichia and Diplodinium significantly decreased.

Effects of B-aminopropionitrile on mineralization during endochondral ossification in chick tibia.

Two-week-old white leghorn chicks were fed a diet containing BAPN (0.05%) for three weeks. Thirty-six hours before sacrifice, the controls and BAPN fed chicks were dosed with 35S. The zone of provisional calcification was isolated, and 35S incorporation was estimated by liquid scintillation counting. Alkaline phosphatase and Ca+2-ATPase were biochemically analyzed. Microdensitometry, to assess the level of mineralization, was done on epiphysis and the metaphysis. Morphometry was performed on the various zones of growth plate. 35S incorporation was significantly lower in the bones of BAPN treated chicks as compared to the controls. The enzymatic studies showed a significant inhibition of alkaline phosphatase and Ca+2-ATPase. The microdensitometric studies showed a smaller area of highly mineralized bone in the zones of provisional calcification of the BAPN treated chicks as compared to the controls. Morphometry showed a reduction in the width of the zone of calcification in BAPN treated chicks as compared to the controls. On the basis of the above data, it is suggested that BAPN induced inhibition of mineralization during endochondral ossification may be the result of a lower synthesis of sulfur containing GAG's, the inhibition of enzymes alkaline phosphatase and Ca+2-ATPase and the derangement of cellular zones of the growth plate. The implications of these results lie in the fact that mineralization is dependent on multifactorial control of the microenvironment of bone and cartilage.

Local effects of impaired mechanical properties of collagen on bone formation and resorption.

To study the relationship between the mechanical properties of collagen and the bone turnover, 2-week-old Balb/C mice were fed on a diet containing 0.25% Beta aminopropionitrile (B-APN), a potent inhibitor of collagen crosslink formation, for 3 weeks. Mandibular incisor socket was selected for the analysis of bone formation and resorption parameters. Plastic embedded sections stained with toluidine blue and cut at 4 microns were used to analyze the average area of bone lamellae, bone-forming surface, and the number of osteoblasts/mm of forming surface. Similar sections were used to localize acid phosphatase on resorbing surfaces and within the osteoclasts, while bone alkaline phosphatase was determined by a colorimetric method. Morphometric analyses showed that the area of newly formed bone lamellae, total forming surface, number of osteoblasts and the Alk. Pase activity were significantly lower in B-APN-fed mice as compared to the controls. There was a concomitant smaller, but significant, reduction in total resorption surface, active resorption surface and the number of osteoclasts. These results suggest that the regulation of bone formation and resorption at this site, which is independent of systemic regulation, is influenced by the mechanical properties of the collagenous matrix, which in turn may have a significant effect on the existing pool of bone-forming cells, but may not influence the recruitment of new cells.