Digital prediction of smile line transition by using 2D photowrapping.

Dental practitioners often rehabilitate patients with excessive gingival display during the broad wide smile. The transition line is defined as the lip line, which depicts transition between the prosthesis and adjacent soft tissue. Correctly predicting and managing this transition line is especially important, as it determines esthetics when the patient smiles widely. Photowrapping is a digital technique used to trace the transition line on digital imaging and communications in medicine (DICOM) files by wrapping a 2-dimensional photograph onto the image, providing the soft tissue information required for esthetics and helping clinicians to determine accurately the need for bone reduction during implant planning. The imaging software program (Dolphin 3D; Patterson Dental Holdings, Inc) and photographs are used in this technique. This article presents a digital technique for tracing the dynamic smile line by photowrapping around the DICOM image.

Effect of rehabilitation by using the shortened dental arch concept on the thickness of the masseter muscle and occlusal force: A pilot study.

STATEMENT OF PROBLEM: Knowledge of the effect of a shortened dental arch on masseter muscle thickness and occlusal force is sparse but could help clinicians understand how a shortened dental arch might affect the stomatognathic system. PURPOSE: The purpose of this pilot clinical study was to evaluate and compare the masseter muscle thickness and occlusal force of participants rehabilitated by using a shortened dental arch with matched completely dentate individuals. MATERIAL AND METHODS: Twelve partially edentulous participants with a minimum of 1 posterior occluding pair on each side of the arch were enrolled in the study. The mandibular arch of these participants was rehabilitated by using a single posterior mandibular implant crown (group S). The maxillary arch of all participants in group S was intact. Masseter muscle thickness (cm) and occlusal force (N) were recorded before (T1) and 6 months after implant rehabilitation (T2) for each participant. Twelve participants were selected as controls (group C). They were matched for age, sex, height, and weight with group S and evaluated for masseter muscle thickness and occlusal force. Masseter muscle thickness was evaluated by using ultrasonography during the rest position and maximum volumetric clenching. Occlusal force was measured with an occlusal force measuring appliance. All recordings were done for the left and right sides of the arch. Descriptive analysis was followed by comparison between groups and within group S by using the paired t test (α=.05). RESULTS: Higher masseter muscle thickness and higher occlusal force were observed in group C than in group S before and after rehabilitation. An increase in masseter muscle thickness in the rest position and in maximum volumetric clenching was observed within group S after rehabilitation. Before rehabilitation, a difference in the masseter muscle thickness between group S and group C was statistically significant for the left side at the rest position (P=.017) and during maximum volumetric clenching (P=.016). After rehabilitation, the difference between group S and group C was not statistically significant for masseter muscle thickness at the rest position (P=.890 for right side and P=.555 for left side) and during maximum volumetric clenching (P=.109 for right side and P=.755 for left side). The difference in occlusal force between group S and group C was statistically significant for the right side and left side (P<.001) before rehabilitation and statistically not significant after rehabilitation (P=.161 for the right side and P=.134 for the left side). CONCLUSIONS: Rehabilitation following the concept of a shortened dental arch increased masseter muscle thickness and occlusal force in partially edentulous individuals, making the masseter muscle thickness and occlusal force comparable with those of a completely dentate arch.

Soil degradation kinetics of oxybenzone (Benzophenone-3) and toxicopathological assessment in the earthworm, Eisenia fetida.

A preponderance of recent evidence indicates that oxybenzone and other personal-care product chemicals threaten the biota inhabiting various ecological niches. What is understudied is the ecotoxicological impact of oxybenzone, a UV filter in sunscreens and anti-aging products, to terrestrial/soil organisms that are keystone species in these habitats. In the present study, acute exposure (14-day) to oxybenzone resulted in earthworm mortality (LC50 of 364 mg/kg) and growth rate inhibition. Environmentally relevant concentration of oxybenzone (3.64, 7.28 and 36.4 mg/kg) at exposures of 7-day, 14-day, 28-day induced oxidative stress and neurotoxicity followed by perturbations in reproduction processes and changes in vital organs. Decreased levels of superoxide dismutase (SOD) and catalase (CAT) activity were statistically lower than controls (p < 0.05) on day 14 for all three concentrations, while glutathione-s-transferase (GST) activity was significantly elevated from controls on days 7 and 14. On day 28, SOD and CAT activities were either not significantly different from the control or were higher, demonstrating a temporal multiphasic response of anti-oxidant enzymes. GST activity on day 28 was significantly reduced compared to controls. Acetylcholinesterase levels across the three-time points exhibited a complicated behaviour, with every exposure concentration being significantly different from the control. Chronic exposure negatively influences earthworm health status with elevated biomarker values analysed using IBRv2 index. This, in turn, impacted higher levels of hierarchical organization, significantly impairing reproduction and organismal homeostasis at the histological level and manifesting as decreasing cocoon formation and successful hatching events. Thus, the overall findings demonstrate that oxybenzone is toxic to Eisenia fetida at low-level, long-term exposure. Based on the concentration verification analysis and application of the EPA PestDF tool, oxybenzone undergoes single first-order kinetics degradation in OECD soil with DT50 and DT90 as 8.7-28.9 days, respectively.

Nabumetone induced photogenotoxicity mechanism mediated by ROS generation under environmental UV radiation in human keratinocytes (HaCaT) cell line.

Nabumetone (NB) is a non-steroidal anti-inflammatory drug (NSAID), prescribed for managing pain associated with acute/chronic rheumatoid arthritis, osteoarthritis and other musculoskeletal disorders. Though some incidences of photosensitivity have been reported, there is limited information available on its phototoxicity potential. In this study, NB photodegraded in a time-dependant manner (0-4 h) under UVA (1.5 mW/cm2), UVB (0.6 mW/cm2) and natural sunlight as observed through UV-vis spectrophotometer and the results were further confirmed with Ultra High-Performance Liquid Chromatography (UHPLC). Photosensitized NB generated reactive oxygen species (ROS) as observed by lipid peroxidation, suggesting oxidative degradation of lipids in cell membrane, thereby resulting in cell damage. MTT and NRU (neutral red uptake) assays revealed that NB induced phototoxicity in concentration-dependent manner (0.5, 1, 5, 10 µg/ml) under UVA, UVB and sunlight exposure (30 min) in human keratinocytes cell line (HaCaT), with significant phototoxicity at the concentration of 5 µg/ml. Photosensitized NB generated intracellular ROS, disrupted mitochondrial and lysosomal membrane integrity, resulting in cell death. UV-induced genotoxicity by NB was confirmed through micronuclei generation, γ-H2AX induction and cyclobutane pyrimidine dimer formation. This is the first study which showed the phototoxicity and photogenotoxicity potential of NB in HaCaT cell line. We also observed that photosensitized NB upregulated inflammatory markers, such as COX-2 and TNFα. This study proposes that sunlight exposure should be avoided by patients using nabumetone and proper guidance should be provided by clinicians regarding photosensitivity of drugs for better safety and efficacy.

Evaluation of the wear of glazed and polished zirconia crowns and the opposing natural teeth: A clinical pilot study.

STATEMENT OF PROBLEM: Clinical studies on the wear properties of different zirconia surfaces are lacking. Selecting a surface that causes and undergoes minimal wear will help improve clinical outcomes. PURPOSE: The purpose of this clinical study was to evaluate and compare the wear over 1 year use of glazed zirconia (GZ) and polished zirconia (PZ) crowns opposing natural enamel and the wear of natural enamel opposing PZ and GZ crowns. MATERIAL AND METHODS: This prospective, split mouth, randomized clinical trial included 14 participants requiring complete coverage crowns on first molars, bilaterally, in a completely dentate mandibular arch. GZ and PZ crowns were cemented according to a randomization chart. Polyvinyl siloxane impressions were made immediately and 1 year after the cementation of the crowns. The respective casts were scanned by using a 3D scanner and a software program to measure the amount of linear wear of zirconia crowns and opposing natural teeth. Wear was observed in 8 groups: PZ crowns, GZ crowns, natural enamel opposing natural enamel in the molar and premolar regions (NE-M and NE-PM), natural enamel opposing PZ crowns in the molar region (NE-PZ-M), natural enamel opposing GZ crowns in the molar region (NE-GZ-M), natural enamel opposing PZ crowns in the premolar region (NE-PZ-PM), and natural enamel opposing GZ crowns in the premolar region (NE-GZ-PM). A descriptive analysis was followed by comparison between groups by using a repeated-measure ANOVA with post hoc adjustments (α=.05). RESULTS: The mean wear (µm) observed was as follows (in ascending order): PZ crowns (13 ±3), NE-PM (13 ±1), GZ crowns (27 ±9), NE-M (34 ±3), NE-PZ-PM (44 ±18), NE-PZ-M (63 ±22), NE-GZ-PM (69 ±21), NE-GZ-M (113 ±33). Wear of GZ and PZ crowns was less than wear of NE-M. The difference was statistically significant when comparing PZ with NE-M (P<.001, CI=-17 to -24). Wear of NE-GZ-M and NE-PZ-M was higher than wear of NE-M, with a statistically significant difference (P<.001, CI=-49 to -107 and P =.004, CI=-8 to -49, respectively). Wear of NE-GZ-M was more than that of NE-PZ-M, and the difference was statistically significant (P<.001, CI=-68 to -32). Wear of NE-PZ-PM and NE-GZ-PM was also more than the wear of NE-PM, and the difference was statistically significant (P<.001, CI=-17 to -43 and P<.001, CI=-39 to -70). CONCLUSIONS: PZ and GZ crowns wear substantially with time, with lesser wear observed in PZ crowns. PZ and GZ crowns also cause more wear in opposing natural enamel than natural enamel antagonists, with the highest wear caused by GZ crowns.

Post-harvest calcium chloride treatments influence fruit firmness, cell wall components and cell wall hydrolyzing enzymes of Ber (Ziziphus mauritiana Lamk.) fruits during storage.

Ber fruits of two varieties having variable shelf lives viz. Umran (8-9 days) and Kaithali (4-5 days) given post-harvest treatments of calcium chloride (1% and 2%) were analyzed for various cell wall components, cell wall hydrolyzing enzymes and fruit firmness at 2 days interval until complete decay. There was a continuous decrease in cellulose, hemicellulose and pectin contents during storage in both the varieties with more reduction in Kaithali, a variety having short shelf-life. The decline in cell wall components was accompanied by parallel increase in activities of cellulase, polygalacturonase (PG) and pectin methylesterase (PME). Post-harvest treatment of Ber fruits with calcium chloride resulted in significantly lowering of activities of cellulase (20-22%), PG (23-29%) and PME (25-28%) thereby retaining higher cell wall components viz. cellulose (9-11%), hemicellulose (7-8%) and pectin (12-13%) as compared to their respective control in both the varieties. The delay in cell wall hydrolysis, as mediated by calcium chloride corresponded to the higher retention of fruit firmness.

Effect of intravenous administration of zoledronic acid on jaw bone density in cases having skeletal metastasis: A prospective clinical study.

AIM: The objective is to evaluate the effect of intravenous (i.v.) administration of bisphosphonate (zoledronic acid) therapy on the jaw bone density and incidence of any other bony patholog. SETTINGS AND DESIGN: Observational - prospective study. MATERIALS AND METHODS: A total of 57 patients having a history of bony metastasis (excluding the jaw bone) were enrolled following the inclusion/exclusion criteria. Each patient received six doses of 4 mg i.v. bisphosphonate once a month. Multidetector computed tomography (MDCT) of jawbones for each patient was performed before the start of therapy (baseline) and subsequently at 6 and 12 months. Bone density was assessed at 24 predetermined sites (8 sites in maxilla and 16 sites in mandible) and any pathological change in either of the jaw bones was noted. STATISTICAL ANALYSIS USED: Shapiro-Wilk test ,Pearson's Chisquare test and repeated measures analysis of variance. RESULTS: The result showed no statistically significant increase in mean bone density over a period of 1 year in maxilla and mandible. However, a significant increase in bone density was observed from 6 months to 1 year in mandibular anterior cancellous bone. The detailed observation of each MDCT scan showed no pathological change in either of the jaw bones during the study period. CONCLUSION: The administration (i.v.) of six doses of 4 mg bisphosphonate did not lead to a significant change in bone density over a period of 1 year.

Prosthodontic rehabilitation of combined oronasal defect in patients with non-Hodgkin's lymphoma using two different attachments: Two case reports.

Debridement of affected parts in patients with non-Hodgkin's lymphoma leads to large mid facial defects leading to poor quality of life due to cosmetic disfigurement and various functional comorbidities. Therefore, a surgeon should refer the patients to a prosthodontist for replacement of lost tissues to improve their function and esthetics. Two cases have been presented here with a history of non-Hodgkin's lymphoma having large, continuous defects involving nose, cheeks, and maxilla. Retaining large facial prosthesis and intraoral obturator was a challenge as supporting hard and soft tissues were less. Two-piece lightweight prostheses were fabricated and retained with the use of very economical titch buttons used (used in clothes) in case 1 due to financial constraints and slightly expensive iron boron neodymium magnets in case 2. Functional and esthetic rehabilitation was successfully achieved with intraoral and facial prostheses attached to each other.

Influence of different forms and materials (zirconia or titanium) of abutments in peri-implant soft-tissue healing using matrix metalloproteinase-8: A randomized pilot study.

STATEMENT OF PROBLEM: It is unclear how pathogenic bacteria adhere to different implant materials and whether biomarker matrix metalloproteinase-8 (MMP-8) level provides a reliable method of evaluating the connective tissue status of peri-implant tissues. PURPOSE: The purpose of this pilot clinical study was to evaluate peri-implant connective tissue response by assessing the MMP-8 levels in peri-implant crevicular fluid around titanium and zirconia abutments. MATERIAL AND METHODS: The study was designed as a prospective, within-subject comparison with left-right randomization low. Twelve participants with partial edentulism were selected according to inclusion and exclusion criteria. Peri-implant sulcal fluid sampling and pocket probing depths were assessed at 1, 3, and 12 months after placing the abutments. The MMP-8 protein level of the peri-implant sulcal fluid was determined by MMP-8-specific sandwich enzyme-linked immunosorbent assay system. The independent t test or Wilcoxon test was used to compare MMP-8 levels and probing depth assessment between the zirconia and titanium groups at different time points (1, 3, and 12 months). Repeated measures ANOVA was used for within-group comparison of the MMP-8 levels at 3 time points (α=.05). RESULTS: At 1 and 3 months, the titanium abutments showed significantly higher MMP-8 levels and probing depths than the zirconia abutments (P<.05), but no significant differences were found at 12 months for either variable (P>.05). CONCLUSIONS: This study suggests the presence of more remodeling and/or inflammatory phenomena around titanium implant abutments than around zirconia abutments of a different design during the early stages but not at 1 year.

Effect of denture soft liner on mandibular ridge resorption in complete denture wearers after 6 and 12 months of denture insertion: A prospective randomized clinical study.

PURPOSE: Soft liners act as a cushion between the denture base and the residual ridge. Hence, it is important to study their effect on resorption of mandibular denture bearing area. Therefore, the purpose of this study was to evaluate the influence of soft denture liner on mandibular ridge resorption after 1 year in completely denture wearers. MATERIALS AND METHODS: Twenty-eight completely edentulous patients having age between 45 and 60 years with well-formed ridges in class I jaw relations were selected as per the inclusion and exclusion criterion. Randomization chart was used to enroll participants in experimental and control groups who were given mandibular dentures with and without soft denture liner, respectively. Vertical measurements were made on orthopantomograph and analyzed using Adobe Photoshop 7.0 software at five points, i.e., one at central incisor and two points at right and left first premolars and two in each first molar region. RESULTS: On application of repeated measures analysis of variance, both groups showed a significant change in bone height after denture delivery (P < 0.05). Intergroup comparison (Wilcoxon rank sum test) of bone height in different regions at various time intervals showed statistically significant difference in bone levels (P < 0.05) from baseline to 6 months and baseline to 12months (P < 0.01), while the difference was statistically not significant during 6 and 12 months' period. CONCLUSION: The use of soft denture liner significantly reduces the residual ridge resorption in complete denture wearers as compared to conventional denture wearers (without denture liner) over a period of 1 year.

Rehabilitation of Patient of Glass Cut Injury With Forehead Flap Repositioning and Implant-Retained Nasal Prosthesis.

Traumatic injuries, especially in maxillofacial region, not only lead to physical debilitation but also cause severe psychological distress in the affected individuals. Complete cosmetic and functional rehabilitation of such patients is a challenging task and thus requires a strategic treatment planning and a multidisciplinary team to execute the treatment. This patient report presents a patient who suffered with a severe glass cut injury leading to massive avulsion of face involving forehead, nose, upper lip, and anterior teeth. Patient was rehabilitated with a combined surgical and prosthetic approach, which involved flap repositioning in forehead, nasal and lip regions and an implant-supported nasal prosthesis to replace missing nose. Missing anterior teeth were replaced with fixed dental prostheses.

Translation and validation of Hindi version of Geriatric Oral Health Assessment Index.

OBJECTIVE: The aim of the study was to translate and validate the oral health-related quality of life assessment tool named Geriatric Oral Health Assessment Index (GOHAI) into Hindi language for use in the Indian population. METHODOLOGY: The 12-item GOHAI questionnaire was translated into Hindi, back-translated and compared with the original English version. After pilot testing and appropriate changes, the Hindi version was administered to a group of 500 patients visiting the geriatric medicine clinic in All India Institute of Medical Sciences, New Delhi. The questionnaire was re-administered to 29 participants after a gap of minimum 7 days. The measures for reliability and validity were also assessed. RESULTS: Cronbach's α score (0.79) showed excellent internal consistency. Item-scale correlations varied from 0.06 to 0.75. Test-retest correlation on the 29 patients showed excellent results (ranging from 0.748 to 0.946). Lower GOHAI scores were associated with patient's self-perception of nutritional status, perceptive need for prosthesis, number of posterior occluding pair of teeth. Higher GOHAI scores were seen with patients with removable prosthesis than with edentulous or partially edentulous participants. Age group was also found to be a significant factor for GOHAI scores. CONCLUSION: The Hindi version of GOHAI exhibits acceptable validity and reliability and can be used in the elderly Indian population as a measure of oral health-related quality of life.

Association between dental prosthesis need, nutritional status and quality of life of elderly subjects.

PURPOSE: To determine the effect of prosthesis need on nutritional status and oral health-related quality of life (OHrQoL) in elderly and to check the disparity between prosthesis need and prosthesis want in the Indian elderly. METHODS: A total of 946 geriatric participants reporting to a geriatric medicine clinic were recruited in the study. Mini-nutritional assessment (MNA), geriatric oral health assessment (GOHAI) indices, prosthesis need according to WHO criteria, and prosthesis want was recorded along with age, gender, socioeconomic status and posterior occluding pair. RESULTS: Significant associations exist between prosthesis need and age (p = 0.005), MNA (p = 0.006) and GOHAI (p = 0.000). Prosthesis demand too was influenced by age (p = 0.004), posterior occluding pairs (p = 0.000), MNA (p = 0.012) and GOHAI (p = 0.000). GOHAI was negatively correlated with upper (r = -0.445) and lower prosthesis need (r = -0.460). Participants with some prosthesis need had significantly lower MNA and GOHAI scores as compared to those with no prosthesis need. Though prosthesis need was high (79.7 %), demand was low (39.3 %). CONCLUSION: Prosthesis need affects nutritional status and OHrQoL in elderly, and a wide gap exists between need and want of prosthesis.

Evaluating the Effects of Varenicline on Craving, Withdrawal, and Affect in a Randomized, Double-Blind, Placebo-Controlled Clinical Trial of Varenicline for Smokeless Tobacco Dependence in India.

This study examined changes in tobacco craving, withdrawal, and affect as correlates of efficacy in a phase-2 clinical trial of varenicline for smokeless tobacco dependence in India. Smokeless tobacco users (N = 237) at the All India Institute of Medical Sciences were randomized to placebo or varenicline. Abstinence was defined as cotinine-verified seven-day point prevalence cessation at end of treatment (EOT). General Linear Model repeated measures assessed the effects of treatment condition, time, abstinence state, and interaction effects on changes in craving, withdrawal, positive (PA) and negative affect (NA) from baseline to EOT. All participants showed a significant reduction in withdrawal (p < .001), total craving (p < .001), positive reinforcement (PR) craving (p < .001), and NA (p = .02), and an increase in PA (p = .04) from baseline to EOT. However, there were no differences between placebo and varenicline participants in measures of withdrawal, craving, or affect from baseline to week 3 or at EOT. Significant interactions between time and abstinence state were found for total craving (p = .008), PR craving (p < .001), and withdrawal (p = .001), indicating reductions in these processes among those abstinent vs. those still chewing smokeless tobacco. Additional research is needed concerning the effects of varenicline on craving, withdrawal, and affect among smokeless tobacco users.

Biochemical Validation of Self-Reported Smokeless Tobacco Abstinence among Smokeless Tobacco Users: Results from a Clinical Trial of Varenicline in India.

The validity of self-reported tobacco use is often questioned given the potential for underestimation of use. This study used data from a double-blind, placebo-controlled clinical trial of varenicline for smokeless tobacco dependence in India to evaluate the accuracy of self-reported smokeless tobacco cessation using biochemical validation procedures and to evaluate correlates of reporting inaccuracy. Smokeless tobacco users attending a dental clinic at AIIMS were randomized to placebo or varenicline; all participants received counseling. Detailed smokeless tobacco use was recorded and abstinence was defined as cotinine-verified 7-day point prevalence cessation (cotinine < 50 ng/ml) and breath CO > 10 ppm at the end of 12 weeks of treatment. One-half of study completers (82/165) self-reported abstinence. Biochemical verification confirmed that (65.9%) subjects provided accurate self-reports while (34.1%) participants underreported tobacco use. These data indicate poor agreement between self-reported and biochemically confirmed abstinence (κ = -0.191). Underreporters of tobacco use had significantly higher baseline cotinine (p < 0.05), total craving (p < 0.012), and negative reinforcement craving (p < 0.001) vs. those whose self-reports were correctly verified. These findings provide evidence to support the need for biochemical validation of self-reported abstinence outcomes among smokeless tobacco users in cessation programs in India and identify high levels of pretreatment cotinine and craving levels as potential correlates of false reporting.

Clinical study to evaluate the wear of natural enamel antagonist to zirconia and metal ceramic crowns.

STATEMENT OF PROBLEM: Tooth wear is a complex process, which, if not prevented, may adversely affect the integrity of the stomatognathic system. Different restorative dental materials may affect the amount of wear on natural enamel antagonists. PURPOSE: The purpose of this in vivo study was to evaluate and compare the wear of enamel opposing natural enamel, zirconia, and metal ceramic crowns after 1 year. MATERIAL AND METHODS: Ten participants between 18 and 35 years of age requiring 2 complete crowns, 1 on either side of maxillary or mandibular molar region, and having healthy natural teeth in the opposing arch were selected. For each participant, 1 monolithic polished zirconia crown and 1 glazed metal ceramic crown were fabricated and cemented. To evaluate the wear of the antagonistic natural enamel (premolar and molar), polyvinyl siloxane impressions were made immediately (baseline) and at 1 year after cementation. The wear of natural enamel against natural enamel was evaluated as the control. The resulting casts were scanned (using a 3D white light scanner), and 3D software was used to calculate the maximum amount of linear wear. RESULTS: One-way repeated measures ANOVA was conducted to analyze data. Mean ±SD occlusal wear of the antagonistic enamel 1 year after the cementation of metal ceramic crowns was 69.20 ±4.10 µm for premolar teeth and 179.70 ±8.09 µm for molar teeth, whereas for zirconia crowns, it was 42.10 ±4.30 µm for premolar teeth and 127.00 ±5.03 µm for molar teeth. Occlusal wear of natural enamel opposing natural enamel was 17.30 ±1.88 µm in the premolar region and 35.10 ±2.60 µm in the molar region. The Bonferroni post hoc test revealed that the occlusal wear of antagonistic enamel 1 year after the cementation of a metal ceramic crown was significantly higher (P<.001) than that of an opposing zirconia crown or natural enamel. CONCLUSIONS: Zirconia crowns led to less wear of antagonist enamel than metal ceramic crowns, but more than natural enamel.

Effect of different design preparations on the flexural and fracture strength of fiber-reinforced composite fixed partial dentures: an in vitro study.

PURPOSE: To determine and compare the flexural and fracture strength of three-unit fiber-reinforced composite (FRC) fixed partial dentures (FPDs) using three abutment design preparations. MATERIAL AND METHODS: The flexural and fracture strength of three-unit FRC FPDs were evaluated using three design preparations of the abutments (conventional full crown [group A], box-shaped [group B], and tub-shaped [group C]). Thirty three-unit FRC FPDs were fabricated (10 specimens per group) for the replacement of missing mandibular first molars and were adhesively luted to extracted human teeth. The flexural and fracture strength were determined using a universal testing machine with a steel loading pin of 20 mm diameter with a 3-mm-diameter hardened circular tip. Each specimen was evaluated under SEM to determine mode of failure. RESULTS: Mean fracture strength for group A was 820.00 ± 56.51 N, group B was 536.94 ± 65.62 N, and group C was 501.24 ± 66.71 N. The highest mean flexural strength was found in group A (68.33 ± 4.71 MPa), followed by group B (44.74 ± 5.46 MPa) and lowest in group C (41.77 ± 5.56 MPa). The SEM evaluation showed partial or complete debonding of veneering composite from fiber framework, leaving intact fiber frameworks in all the specimens. CONCLUSION: Full-coverage design had significantly higher flexural and fracture strengths than box and tub-shaped designs. Since both values were noted to be in the order of masticatory stresses, the full coverage design is a good alternative for the replacement of missing molar teeth; however, the framework veneering composite interface was the weakest phase of FRC FPDs, thus indicating that further improvement in veneering composite or fiber framework is needed to improve the compatibility of veneering composite with that of fiber framework for long-term clinical implications.

Comparative evaluation of effects of bleaching on color stability and marginal adaptation of discolored direct and indirect composite laminate veneers under in vivo conditions.

STATEMENT OF PROBLEM: Change in color and loss of marginal adaptation of tooth colored restorative materials is not acceptable. Bleaching is commonly used for treating discolored teeth. However, the literature is scanty regarding its effect on color and marginal adaptation of direct and indirect composite laminate veneers (CLVs) under in vivo conditions. PURPOSE: Purpose of the study was to determine the effect of bleaching on color change and marginal adaptation of direct and indirect CLVs over a period of time when exposed to the oral environment. MATERIALS AND METHODS: For this purpose, a total of 14 subjects irrespective of age and sex indicated for CLV restorations on maxillary anterior teeth were selected following the inclusion and exclusion criteria. For each subject, indirect CLVs were fabricated and looted in the first quadrant (Group 1) and direct CLV's (Group 2), were given in the second quadrant. Color change was assessed clinically using intra-oral digital spectrophotometer and marginal adaptation was assessed on epoxy resin replica of the tooth-restoration interface under scanning electron microscope. After 6 months, the subjects underwent a home bleaching regimen for 14 days using 10% carbamide peroxide. The assessment of color change and marginal adaptation was done at 6 months after veneering (0-180 days), immediately after the bleaching regimen (0-194 days) and 3 months after the bleaching regimen (0-284 days). RESULTS: The difference in median color change (ΔE) between the groups was tested using Wilcoxon rank sum test while the median color change with time within the groups was tested using Wilcoxon signed rank test. The difference in the rates of marginal adaptation was tested between the groups using Chi-square/Fisher's exact test. Bleaching led to statistically significant color change at cervical (CE), middle and incisal (IE) regions when direct and indirect composites were compared (P < 0.05). During intra-group comparison, direct CLV's showed significant color change at CE and IE regions when ΔE was compared at 180 days and 284 days (CE 10 vs. CE 30, P = 0.008, IE 10 vs. IE 30, P = 0.003). No significant differences were found when within group comparison was made for indirect laminates. Intergroup comparison between the groups showed significant difference in marginal adaptation at CE margin at all.time points (at baseline, P = 0.005; at 180 days, P = 0.007; 194 days, P = 0.025; at 284 days, P = 0.067). CONCLUSION: After bleaching, indirect CLVs performed better in terms of color stability whereas direct CLVs performed better in terms of marginal adaptation. CLINICAL SIGNIFICANCE: Indirect composites should be preferred to direct composites as veneering materials as they have better color stability. Special attention should be given to their marginal adaptation especially in the CE region. Bleaching should be avoided in patients with composite restorations in the mouth.

A double-blind placebo-controlled randomized trial of varenicline for smokeless tobacco dependence in India.

INTRODUCTION: The rate of smokeless tobacco use in India is 20%; its use causes serious health problems, and no trial has assessed behavioral or pharmacological treatments for this public health concern. This trial evaluated varenicline for treating smokeless tobacco dependence in India. METHODS: This was a double-blind placebo-controlled randomized trial of varenicline (12 weeks, 1mg, twice per day) with 237 smokeless tobacco users in India. All participants received behavioral counseling. Outcomes included self-reported and biochemically verified abstinence at the end of treatment (EOT), lapse and recovery events, safety, and medication adherence. RESULTS: Self-reported EOT abstinence was significantly greater for varenicline (43%) versus placebo (31%; adjusted odds ratio [AOR] = 2.6, 95% CI = 1.2-4.2, p = .009). Biochemically confirmed EOT abstinence was greater for varenicline versus placebo (25.2% vs. 19.5%), but this was not statistically different (AOR = 1.6, 95% CI = 0.84-3.1, p = .15). Compared with placebo, varenicline did not reduce the risk for a lapse (hazard ratio [HR] = 0.86, 95% CI = 0.69-1.1, p = .14), but it did increase the likelihood of recovery to abstinence (HR = 1.2, 95% CI = 1.02-1.4, p = .02). Greater adherence increased EOT cessation rates for varenicline (39% vs. 18%, p = .003) but not for placebo (28% vs. 14%, p = .06). There were no significant differences between varenicline and placebo in rate of side effects, serious adverse events, hypertension, or stopping or reducing medication. CONCLUSIONS: Varenicline is safe for treating smokeless tobacco dependence in India, and further examination of this medication for this important public health problem is warranted.

Isozymes of antioxidative enzymes during ripening and storage of ber ( Ziziphus mauritiana Lamk.).

Isozyme profile of antioxidative enzymes viz. superoxide dismutase (SOD), peroxidase (POX), catalase (CAT) and ascorbate peroxidase (APX) was studied during ripening and storage of two cultivars of ber fruit (Ziziphus mauritiana Lamk.) differing in their shelf-lives viz. Umran (shelf-life, 8-9 d) and Kaithali (shelf-life, 4-5 d). The profile revealed that Umran variety exhibited three bands each of SOD and POX while in Kaithali, these enzymes had two isoenzymes throughout ripening. CAT and APX, however, showed two isozymes each during ripening of both the varieties and the pattern remained the same at all the stages of ripening except at the initial stage i.e immature green stage where single CAT isozyme was visible. During storage, one extra band each of SOD and POX present only in Umran got disappeared at later stages of storage, whereas in Kaithali, the pattern remained unchanged. Also, there was no change in the pattern of CAT and APX isozymes during storage of both the varieties. One isozyme of CAT could be considered as ripening related while one isozyme each of SOD and POX could be related to higher shelf life of fruits.