Enhancement of progesterone biosynthesis via kisspeptin stimulation: Upregulation of steroidogenic transcripts and phosphorylated extracellular signal-regulated kinase (p-ERK1/2) expression in the buffalo luteal cells.

The presence of Kisspeptin (Kp) and its receptors in the corpus luteum (CL) of buffalo has recently been demonstrated. In this study, we investigated the role of Kp in the modulation of progesterone (P4) synthesis in vitro. The primary culture of bubaline luteal cells (LCs) was treated with 10, 50, and 100 nM of Kp and Kp antagonist (KpA) alongside a vehicle control. The combined effect of Kp and KpA was assessed at 100 nM concentration. Intracellular response to Kp treatment in the LCs was assessed by examining transcript profiles (LHR, STAR, CYP11A1, HSD3B1, and ERK1/2) using quantitative polymerase chain reaction (qPCR). In addition, the immunolocalization of ERK1/2 and phosphorylated ERK1/2 (p-ERK1/2) in the LCs was studied using immunocytochemistry. Accumulation of P4 from the culture supernatant was determined using enzyme-linked immunosorbent assay (ELISA). The results indicated that LCs had a greater p-ERK1/2 expression in the Kp treatment groups. A significant increase in the P4 concentration was recorded at 50 nM and 100 nM Kp, while KpA did not affect the basal concentration of P4. However, the addition of KpA to the Kp-treated group at 100 nM concentration suppressed the Kp-induced P4 accumulation into a concentration similar to the control. There was significant upregulation of ERK1/2 and CYP11A1 expressions in the Kp-treated LCs at 100 nM (18.1 and 37fold, respectively, p < 0.01). However, the addition of KpA to Kp-treated LCs modulated ERK1/2, LHR, STAR, CYP11A1, and HSD3B1 at 100 nM concentration. It can be concluded that Kp at 100 nM stimulated P4 production, while the addition of KpA suppressed Kp-induced P4 production in the buffalo LCs culture. Furthermore, an increment in p-ERK1/2 expression in the LCs indicated activation of the Kp signaling pathway was associated with luteal steroidogenesis.

Differential expression of inflammatory cytokines, prostaglandin synthases and secretory leukocyte protease inhibitor in the endometrium and circulation in different graded CEH-pyometra in bitch.

Cystic endometrial hyperplasia (CEH)-pyometra (CEH-P) is one of the most common reproductive disorders in bitches, posing a risk to both future fertility and life. The aims of the current study were to elucidate the differential expression patterns of inflammatory mediators at transcript and protein levels in the endometrium and to assess the concentrations of key inflammatory mediators in the peripheral circulation of bitches with different graded CEH-P. A total of 25 client-owned intact mixed breed bitches of 3-10 years presented to the outpatient department of RVP-TVCC of the institute were considered for the study. Of which, 22 cases suggestive of pyometra and 3 cases of CEH obtained during routine elective ovariohysterectomy were subjected to histopathological examination. Uteri were categorized into CEH (n = 3), moderate CEH-P (mCEH-P, n = 9), severe CEH-P (sCEH-P, n = 6) and atrophic pyometra (AT-P, n = 7). A group of age matched (n = 12) bitches without pyometra served as control. Endometrial transcripts such as IL6, IL8, PTGS2, PGFS, and SLPI were expressed differentially in the CEH and CEH-P bitch. In addition, a strong immunoreactivity (IR) of IL6, IL8, PTGS2, and mPGES1 was recorded in the sCEH-P uterus, while expression of IL10 was noticed in AT-P. In circulation, serum IL6 was the most relevant marker with high sensitivity of 96.2% and specificity of 84.6% at a cut off concentration 8.5 pg/mL followed by SLPI with 95.2% sensitivity, and 84.6% specificity at cut off concentration of 1.3 ng/mL. Serum IL10, PGFM and SLPI concentration in the peripheral circulation were 1.5-2.23 fold higher in mCEH-P, 0.87-2.5 fold higher in sCEH-P and 2.9-3.5 fold higher in AT-P than that of control. It is concluded that monitoring the serum concentration of IL6, IL10 and SLPI would be useful adjunct to the established hematobiochemical parameters in the management of pyometra in the bitch with critical illness.

A Comparative Analysis of Surface Characteristics of Enamel after Conventional Acid Etching and Er,Cr:YSSG Laser Irradiation.

Background: To evaluate the influence of Erbium, Chromium:Yttrium-Scandium-Gallium-Garnet (Er,Cr:YSGG) laser irradiation (2W 15Hz, 2W 25Hz) on Penetration Depth, Surface Roughness, Surface Morphology and Etching Pattern of enamel and to compare it with conventional acid etching. Material and Methods: Sixty sound human premolars extracted for orthodontic reasons were used for this study. Penetration Depth and Surface Roughness between Acid Etched and Laser Etched Enamel were evaluated using Non-contact 3D- Profilometer .Surface Morphology and the Etching Pattern were evaluated using Field Emission - Scanning Electron Microscope. Results: On comparing the maximum depth and surface roughness values among all the three groups, highest was found in the acid-etched group, followed by the 2W 15Hz laser-etched group and the least was with the 2W 25Hz laser-etched group. The laser etching of enamel surface with an Er,Cr:YSGG laser system showed Type 3 etching pattern, whereas acid etched surface showed Type 1 etching pattern as described by Silverstone (1974). Conclusions: Er,Cr:YSGG laser irradiation produces favourable etching pattern and micro-irregularities that are suitable for resin penetration. Moreover, due to its decreased surface roughness and penetration depth, laser etching can significantly decrease the probability of formation of white spot lesions which is proved to be the potential disadvantage of conventional acid etching. Hence, laser etching can be preferred over the conventional phosphoric acid etching for orthodontic bonding. Key words:Laser, Er,Cr:YSGG, Surface Roughness, Etching Pattern,Penetration Depth,SEM, Laboratory Research, Acid etching.

Expression of kisspeptin and its receptor in different functional classes of ovarian follicle in the buffalo (Bubalus bubalis).

Recently, we reported the differential expression of kisspeptinergic system in the bubaline hypothalamus and corpus luteum. Here, we document the expression of kisspeptin (Kp) and its receptor (Kiss1r) in the ovarian follicles of the buffalo with respect to the functional status. Follicles of ≥10 to ≤13 mm diameter (n = 45) were retrospectively categorized into active (n = 18), intermediate (n = 16) and atretic (n = 11) follicles based on the concentrations of intrafollicular progesterone (P4) and estradiol (E2). The P4:E2 ratio was significantly lower in the active follicle (0.43 ± 0.08) than that of the intermediate (3.46 ± 0.53) and atretic (28.4 ± 10.6) follicles (P < 0.05). Relative fold change in the transcripts of kisspeptin (Kiss1), Kiss1r, gonadotrophin receptors, steroid acute regulatory protein (StAR), cytochrome P450 family 11 subfamily A member 1 (CYP11A1), cytochrome P450 Family 19 subfamily A member 1 (CYP19A1), insulin like growth factor -1 (IGF-1), apoptotic factors (caspase 3 and B-cell lymphoma 2, BCL2) was calculated using qPCR in the follicular wall of the three categories of follicle (n = 8/group). In another experiment, histological sections of the ovary (n = 41) were used to group the follicles as described above and immunostaining of Kp, Kiss1r and aromatase was done. A significant upregulation of StAR, CYP11A1 and CYP19A1 in the active follicles supported the endocrine basis of follicular classification. The transcripts of Kiss1 and Kiss1r were upregulated by 19.45 fold and 4.25 fold, respectively in the active follicle as compared to other groups. Immunolocalization studies revealed that Kp and Kiss1r were localized to the basal and antral granulosa cells (GC) of the active and intermediate follicles; however, the staining intensity was stronger in the former group. Strong expression of CYP19A1 in the GC layer of active follicle supported the histological basis of defining the functional status of the follicle. It is concluded that the follicular compartment of the bubaline ovary expressed the constituents of kisspeptinergic system. The expression of Kp and Kiss1r was influenced by the functional status of the follicle with intense localization in the GC layer of the active follicles.

Characterization of arrhythmias, evaluation of cardiac biomarkers and their association with survival in calves suffering from foot-and-mouth disease.

INTRODUCTION: Foot-and-mouth disease (FMD) causes mortality in calves due to myocarditis; however, the effects of FMD virus on cardiac arrhythmogenesis and Purkinje cells are unknown. Identifying diagnostic and prognostic markers in FMD-affected calves may be useful in disease management in the endemic countries. MATERIALS AND METHODS: A total of 81 FMD-affected calves were prospectively monitored till death or recovery. Foot-and-mouth disease was diagnosed by serology and reverse transcriptase-polymerase chain reaction (RT-PCR). Electrocardiography was recorded and serum cardiac biomarkers were measured. Histopathological examination of the ventricular myocardium was carried out in the calves that died of FMD (n = 33). Apparently healthy calves (n = 15) served as control. RESULTS: Serology and RT-PCR consistently revealed that the FMD was caused by serotype O virus. Arrhythmias occurred in 62 of 81 (76.5%) FMD-affected calves, of which, ventricular premature complexes (VPCs) were the most common type (22%). The combined mortality rate due to ventricular tachycardia, polymorphic VPCs, and atrial fibrillation was 27.6%. Receiver operating characteristic curve analysis revealed that cardiac troponin I (cTnI) concentrations of ≥1.3 ng/mL were diagnostic of myocarditis with a sensitivity and specificity of 90% and 100%, respectively. Similarly, serum cTnI concentrations of <6.4 ng/mL were a good predictor of survival [odds ratio of 263; 95% confidence interval: 29-2371]. Histopathology of the myocardium revealed hyaline degeneration, necrosis, edema, mononuclear cell infiltration, and disruption by fibroblasts. Atrophy of the Purkinje cells was also present. CONCLUSIONS: FMD induces cardiac arrhythmias and Purkinje cell pathology in the calf. Portable ECG coupled with assay of serum cTnI would help in predicting survival in FMD-affected calves.

Influence of seasonal variation on post-farrowing dysgalactia syndrome (PFDS) and serum biochemistry profiles in the periparturient sow.

The objective of this study was to investigate the effect of seasonal variation on the frequency of post-farrowing dysgalactia syndrome (PFDS), sow body condition score (BCS), piglet survival, and weaning to estrus interval under intensive management systems. In addition, the effects of PFDS on litter characteristics and serum biochemistry, oxidative stress indices, thyroid, and cortisol profile were examined in order to identify potential biomarkers in the pre-farrowing stage. The study was conducted in summer and winter seasons in Nagaland, India, on 50 sows from 30 days before farrowing until weaning at 45 days. Sows were classified retrospectively into PFDS and non-PFDS. Although statistically, no significant difference was noted in the occurrence of PFDS between the seasons, the proportion of PFDS development was substantially higher in winter than summer (37.5 vs. 26.9%). In winter, the incidence of piglet stillbirth and sow weaning to estrus period was significantly higher (p < 0.05) and the mean litter size at weaning was significantly lower (p < 0.01). At weaning, the mean litter weight and average daily weight gain were decreased (p < 0.05) in both summer and winter, and the total number of piglets died in each litter was increased in sows afflicted with PFDS compared with healthy sows. A significant interaction effect of peripartum days and PFDS was observed in the changes of blood glucose, albumin (p < 0.05), and HDL-cholesterol (p = 0.07) concentration. Mean T3 and T4 concentration was influenced by peripartum days in both the season and a consistently lower T3 concentration was detected in PFDS sows before farrowing. It is concluded that PFDS sows exhibited an increased incidence of stillbirth and scouring of neonatal piglets during the winter. A pronounced drop in mean circulating T3 concentration in sows from 30 days before farrowing to 3 days after farrowing reflects endocrine-mediated metabolic dysfunction. Further research is warranted with more number of sows to identify the critical values of serum T3 concentration in the immediate pre-farrowing period for prediction of sows developing PFDS after farrowing.

Foot and mouth disease virus undergoes non-progressive replication in mice peritoneal macrophages and induces M1 polarization.

Despite the fact that macrophages link the innate and adaptive arms of immunity, it's role in the early infection of foot and mouth disease virus (FMDV) is largely unknown. Recently, depletion of macrophages in vivo after vaccination has shown to drastically diminish the protection against FMDV challenge in mouse model. Even the ability of macrophages to reduce or resist FMDV infection is not known hitherto. Therefore, we examined the replication ability of FMDV in mice peritoneal macrophages and the responsiveness in terms of macrophage polarization and cytokine production. Negative strand specific RT-PCR indicated replication of FMDV RNA in macrophages. Absolute quantitation of FMDV transcripts, immunofluorescence studies and titre of the infectious progeny virus revealed that replication peaked at 12 hpi and significantly declined by 18 hpi indicating non-progressive replication in the infected macrophages. Further, significant up regulation of inducible nitric oxide synthase by 8 -12 hpi and increase of M1 specific CD11c + cells by 42.6 % after infection showed that FMDV induce M1 polarization. A significant up regulation of TNFα and IL12 transcripts at 8 hpi supported that M1 macrophages were functional. Further, we studied the expression of Type I to III interferons (IFN) and other antiviral molecules. The results indicate a marked up regulation of Type I IFNα and ß by 9.2 and 11.2 fold, respectively at 8 hpi. Of the four IFN stimulated genes (ISG), viperin showed a significant up regulation by 286-fold at 12 hpi in the mice macrophages. In conclusion, the results suggest that replication of FMDV in mice peritoneal macrophages is non-progressive with up regulation of Type I IFN and ISGs. Further, FMDV induces M1 polarization in murine peritoneal macrophages.

Comparison of chemical extraction methods for determination of 146S content in foot-and-mouth disease oil-adjuvanted vaccine.

AIMS: To compare antigen extraction efficiency of chemical methods such as benzyl alcohol, chloroform, sodium citrate, extraction buffer with Tween-20 (EBT) and isopropyl myristate for determination of 146S content in the fresh and stored FMD oil-adjuvanted vaccines. METHODS AND RESULTS: Standard vaccine with antigen payload of 10, 5 and 5 µg per cattle dose (2 ml) for serotypes O, A and Asia1, respectively, was used to compare the antigen extraction efficiency of five chemical methods: benzyl alcohol, chloroform, sodium citrate, EBT buffer and isopropyl myristate. The purity of the extracted 146S antigen was quantified by caesium chloride (CsCl) ultracentrifugation. Serotype-specific sandwich ELISA (sELISA) was developed to identify the serotype and to compare the 146S in aqueous phase and ultrafractions. The antigen recovery was also tested in stored trivalent vaccine. Coefficient of regression was calculated to assess the predictive power of the benzyl alcohol extraction method. Of the five methods, benzyl alcohol showed consistent antigen recovery of >90% in monovalent as well as trivalent vaccines. Ultrafraction showed a 1·4 ratio at A259/239 nm in UV spectrophotometry indicating the presence of 146S. sELISA revealed that the antigen recovery was significantly less in ultrafractions than that of aqueous phase. Further, there was no significant difference in antigen recovery from stored trivalent vaccine for 12 months, indicating the usefulness of the benzyl alcohol method. Linear regression model revealed R2  = 0·99 with a narrow band of predictive interval. CONCLUSIONS: The benzyl alcohol method was efficient in extracting 146S from the monovalent and trivalent fresh and stored FMD vaccines. CsCl density gradient precisely quantified the 146S, while sELISA identified the serotype of the vaccine. SIGNIFICANCE AND IMPACT OF THE STUDY: When the benzyl alcohol method is coupled with CsCl density gradient and sELISA, it has the potential to determine the 146S content of FMD vaccine.

Expression of Kisspeptin and its receptor in the hypothalamus of cyclic and acyclic buffalo (Bubalus bubalis).

Kisspeptin (Kiss1), neurokinin-B (NKB) and dynorphin (Dyn) neurons regulate the surge and pulsatile centres of gonadotropin releasing hormone (GnRH) in the hypothalamus and are modulated by the ovarian steroids. Accordingly, we studied the temporospatial expression of Kiss1, its receptor and other genes that regulate GnRH in the preoptic area (POA) and arcuate (ARC) regions of hypothalamus at different phases of bubaline estrous cycle. Brain of buffalo (n = 32) was collected immediately after exsanguination and categorized into early luteal (EL), mid luteal (ML), follicular (FL) stages and acyclic (n = 8/group). Total RNA was extracted from the POA and ARC of each stage and real time PCR amplification of Kiss1, Kiss1r, NKB, NKB receptor (NKBR), Dyn, Dyn receptor (OPRK1), GnRH1, ERα, PR, LEPR and GHSR was done using GAPDH as endogenous control and acyclic stage as calibrator group. Further, immunolocalization of Kiss1 and Kiss1r was done on the hypothalamus. In the POA, significant up-regulation of Kiss1 and NKB with a concomitant down-regulation of Dyn transcripts was recorded at FL stage. There was, however, down-regulation of Kiss1 and Kiss1r during the EL perhaps due to the loss of estradiol as a consequence of ovulation. On the other hand, in the ARC, there was a significant up-regulation of Kiss1 and Dyn at FL and ML, while NKB transcript was consistently down-regulated at any stage of estrous cycle. In the POA, expression of ERα was not modulated; however, PR was down-regulated in the EL. In the ARC, the ERα expression was significantly up-regulated in the EL, whereas, PR was moderately expressed irrespective of the stage of estrous cycle. The immunolocalization study revealed the presence of Kiss1 and Kiss1r in the POA and ARC in the cyclic buffalo with relative abundance at FL. The transcriptional profile of the genes suggests that there is estrous cycle stage specific expression of Kiss1, Kiss1r and other GnRH regulating genes in the POA and ARC regions of hypothalamus in the buffalo. Up-regulation of Kiss1r in the POA during ML and ARC during EL indicates the involvement of kisspeptinergic system in the regulation of low LH pulse frequencies during the early and mid luteal phases in the cyclic buffalo.

Generation of acid resistant virus like particles of vaccine strains of foot-and-mouth disease virus (FMDV).

Foot-and-mouth disease (FMD) is a contagious viral disease affecting cloven hoofed livestock. Insect cell expressed virus like particles (VLPs) are potential alternative to overcome the limitations of inactivated vaccine. However, at pH < 6.5, virus particles disassociate into pentameric structure resulting in loss of antigenicity. Accordingly, we generated seven mutant VLPs containing mutations in the structural genes of FMDV vaccine strains (N17D and/or H145Y for serotypes O/IND/R2/75 and Asia1/IND/63/72; and H142D for serotype A/IND/40/00) by PCR based site directed mutagenesis. Acid resistant VLPs produced by baculovirus expression system were tested for acid stability at pH 7.5, 6.5, 6.0 and 5.5 followed by reactivity in sandwich-ELISA (s-ELISA), which revealed mutant-1 (N17D) of serotype O and Asia1 retained the antigenicity in s-ELISA even at pH 5.5 as compared to other VLPs and wild-types. Further, the 75S empty capsids obtained in sucrose density gradient, when tested in liquid phase blocking ELISA (LPBE) in comparison to cell culture antigen indicated that the VLPs were stable at acidic pH. Transmission electron microscopy of OM-1 confirmed the intact morphology of the empty VLPs. It is concluded that acid resistant VLPs could be useful for developing new generation vaccine or diagnostic for FMDV.

Ovulatory and fertility response using modified Heatsynch and Ovsynch protocols in the anovular Murrah buffalo (Bubalus bubalis).

We studied the effect of modified Heatsynch and Ovsynch protocols on the ovulatory response (OR), estrus induction rate (EIR) and conception rate (CR) in the anovular postpartum Murrah buffalo (n = 35). In the modified Heatsynch protocol (Group I; n = 12), buffaloes were given two GnRH at 2 h interval on treatment day 0, PGF (PGF2α) on day 7 and estradiol (E2) 1 mg on day 8. Two FTAI were done at 20 h intervals after E2 administration. In the modified Ovsynch protocol (Group II; n = 15), GnRH was given on day 0, 7 and 16 with a PGF on day 14. Two FTAI were done; one at last GnRH and the other 20 h later. Group III served as untreated negative control (n = 8). During the treatment, ovarian changes were monitored by transrectal ultrasonography and plasma progesterone (P4) and E2. Administration of two GnRH at 2 h interval neither increased the OR nor strengthened the subsequent P4 priming. Interestingly, in group I, none of the buffalo ovulated to E2 though the EIR was 100% indicating the occurrence of behavioral, but not ovulatory estrus. Administration of GnRH 7 day prior to the commencement of Ovsynch protocol (Group II) did not improve the CR (21.4%), though the OR was 71.4%. No significant difference was found in the diameter of largest follicle between the ovulated and non-ovulated buffalo in response to GnRH suggesting that follicle of ≥9.5 mm is necessary but not sufficient to induce ovulation in the anovular buffalo. In both the protocols, the plasma P4 was higher on day 7 in those buffaloes that ovulated to GnRH. Buffaloes treated with modified Ovsynch regimens were 5.27 times more likely to become pregnant than modified Heatsynch protocol. It is concluded that modified Ovsynch protocol is superior to modified Heatsynch protocol in terms of OR and CR.

Spatial molecular epidemiology of carbapenem-resistant and New Delhi metallo beta-lactamase (blaNDM)-producing Escherichia coli in the piglets of organized farms in India.

AIM: A cross-sectional study was conducted in 10 government-organized pig farms between 2014 and 2016 representing seven states of India to understand the epidemiology of carbapenem resistance in the Escherichia coli. METHODS AND RESULTS: In this study, fecal sample (n = 673) from non-diarrheic (n = 501) and diarrheic (n = 172) piglets were processed for isolation of carbapenem resistant E. coli. Of 673, E. coli isolate (n = 112) was genotyped for confirming the carbapenem resistance and associated virulence factors. Of the 112 isolates, 23 were phenotypically resistant to carbapenem and 8 were carrying the New Delhi metallo beta-lactamase (blaNDM) gene. The carbapenem-resistant isolates also produced extended spectrum beta-lactamases and were multidrug resistant. The PCR-based pathotyping revealed the presence of stx1, stx2, eae and hlyA genes. The enterobacterial repetitive intergenic consensus PCR dendrogram analysis of the isolates yielded three distinct clusters. The statistical analysis revealed no association between carriages of carbapenem-resistant E. coli in different breed of piglets however, location, sex, health status of piglets and age showed significant difference. The spatial analysis with SaTScan helped in identification of carbapenem-resistant clusters. CONCLUSIONS: The presence of carbapenem resistant E. coli isolates with virulence genes in the piglet poses a potential public health risk through possible access and spread via the food chain and environment. Efflux pump may also play an important role in carbapenem resistance in piglet E. coli isolates. Furthermore, identification of risk factors in relation to spatial clusters will help in designing preventive strategies for reducing the risk of spread of carbapenem resistant bacteria. SIGNIFICANCE AND IMPACT OF THE STUDY: 1. Piglets harbor carbapenem resistant E. coli and have great public health significance. 2. Apart from carbapenemase, efflux pump is also important for carbapenem resistance. 3. This is the first report of blaNDM in the piglets from India.

Relationship between endometritis and oxidative stress in the follicular fluid and luteal function in the buffalo.

In this study, alteration in the follicular fluid composition and luteal function was investigated in the buffalo with endometritis. Genitalia were classified into cytological and purulent endometritis on the basis of polymorphonuclear cell cut off while non-endometritis served as control (n = 10/group). In the follicular phase, the number of surface follicles was counted, diameter of the largest follicle was measured and the follicular fluid was assayed for total protein, cholesterol, malondialdehyde (MDA), total antioxidant capacity (TAC), oestradiol (E2 ) and progesterone (P4 ). The P4 content of corpus luteum during mid-luteal phase was estimated by radioimmunoassay. Ovaries from the follicular phase of oestrous cycle showed no significant difference in the total number of surface follicles, size of the largest follicle and volume of follicular fluid in the buffaloes with and without endometritis (p > .05). However, the antral fluid of the largest follicle from the genitalia of buffalo with cytological and purulent endometritis showed a significant decrease in the concentration of total protein, cholesterol, TAC and E2 and a significant increase in the concentration of MDA and P4 (p < .05). The results indicated that there is an association between endometritis and decreased ovarian function.

Comparison of shear bond strength of self-etching fluoride releasing adhesives with and without pumice prophylaxis.

CONTEXT: Despite the advances in orthodontic material and treatment mechanics, the placement of fixed appliances increases the risk of enamel demineralization. The development of fluoride release adhesives has attracted considerable interests because the combined use of antimicrobials and fluoride enhances the cariostatic effect. AIM: To compare the shear bond strength (SBS) of fluoride release adhesives with established orthodontic adhesives and assess failure mode using adhesive remnant index (ARI). SETTINGS AND DESIGN: The present study included 80 maxillary premolars which were randomly divided into four groups (n = 20) and were further subdivided into two subgroups A - Pumice prophylaxis (PP) and subgroup B - No PP (n = 10). MATERIALS AND METHODS: Stainless steel brackets were bonded with Transbond XT, Transbond plus (TP) color change adhesive, Light Bond, and Clearfil protect bond. After debonding, the ARI was used to assess the mode of bracket failure. STATISTICAL ANALYSIS: The data were analyzed using two-way analysis of variance, Post-hoc Tukey Honest significant differences test, and Chi-square test. RESULTS: The mean SBS of Group 4 was comparably higher regardless of PP. Brackets bonded with TP showed a comparable SBS to conventional Transbond XT. The ARI scores were predominately 2. CONCLUSIONS: Fluoride releasing adhesives combined with antibacterial monomer can play a vital role in reducing white spot lesions by enhancing the cariostatic effect especially in noncompliant\medically compromised patients.

Comparison of shear bond strength of orthodontic brackets bonded using two different hydrophilic primers: an in vitro study.

CONTEXT: Salivary control and maintenance of a dry operating field is a prime requisite of orthodontic bonding. Moisture insensitive primer (MIP) with a clinical significant bond strength values have a better edge over the conventional hydrophobic bonding systems. AIM: The aim of this study is to investigate the effectiveness of two hydrophilic primers with respect to conventional hydrophobic primer by comparing their shear bond strength (SBS) and adhesive-failure locations after contamination with saliva and saliva substitute. MATERIALS AND METHODS: A total of 150 extracted human premolars were randomly divided into five groups; Group A (Transbond MIP/saliva substitute), Group B (Opal Primo/saliva substitute), Group C (Transbond MIP/natural saliva), Group D (Opal Primo/natural saliva), control group - Group E (Transbond XT/dry), adhesive-Transbond XT used for all five groups and bonded using stainless steel brackets. Shear forces were applied to the samples with a universal testing machine. SBSs was measured in megapascals. The mode of bond failure was determined using the adhesive remnant index (ARI). RESULTS: The mean SBS produced by Transbond MIP was higher than Opal Primo, which was statistically significant according to one-way analysis of variance. Both the tested groups showed lesser bond strength values than Transbond XT (the control). ARI scores revealed that there was no statistically significant difference in the site of bond failure between study groups. ARI scores were found to be lower for study groups suggesting adhesive failure, compared to higher ARI scores for the control group suggesting cohesive failure. CONCLUSION: Transbond XT adhesive with Transbond MIP or Opal Primo have clinically acceptable bond strength in wet fields. Opal Primo is a viable option to use as a hydrophilic primer clinically.

Corticotomy-assisted retraction: an outcome assessment.

BACKGROUND: To assess the efficiency and treatment outcome of patients treated with corticotomy-assisted en-masse orthodontic retraction as compared with the en-masse retraction without corticotomy. MATERIALS AND METHODS: Forty adult patients with bimaxillary protrusion requiring correction of bidental proclination constituted the sample. The study group consisted of 22 patients (male 11, female 11) willing to undergo surgery to reduce the duration of their orthodontic treatment and 18 patients (male 9, female 9) desirous of undergoing conventional orthodontic treatment without surgical intervention constituted the control group. Comparison of rate of retraction and anchor loss between the study and the control group was assessed. RESULTS: Average rate of space closure of 1.8 mm/month in the maxilla and 1.57 mm/month in the mandible was observed in the study group compared to 1.02 mm/month in the maxilla and 0.87 mm/month in the mandible in the control group. The rate of retraction accelerated during the first 2 months of retraction. Molar anchor loss of approximately 0.6 mm occurred in the study group, and 1.8 mm occurred in the control group during the 4 months. CONCLUSION: The rate of retraction with study group was twice as faster when compared to the control group, accelerating during the first 2 months of retraction. There was better anchorage control with the undecorticated molar segment during the retraction period but was found to increase as time advanced.

Comparison of shear bond strength of hydrophilic bonding materials: an in vitro study.

AIM: The aim of this study was to evaluate and compare the shear bond strength of hydrophilic materials like Transbond MIP with Assure-fluoride releasing light cure sealant paste system (Reliance orthodontic product), Enhance Lc-adhesion booster (Reliance Orthodontics) Prime and Bond NT-one step adhesive with nanotechnology (Dentsply Product India) with Transbond XT as the control group. MATERIALS AND METHODS: The study was conducted on 180 extracted human premolar teeth which were divided into five main groups. Each group contained 36 teeth, which were further subdivided into three subgroups containing 12 teeth. The teeth were bonded in three different surface environments namely dry, contaminated with artificial saliva and reprimed after contamination with artificial salvia. The brackets were bonded and cured. The shear bond strength was tested using Instron universal testing machine (4501). RESULTS: The results were subjected to statistical analysis like 3 factorial ANOVA and compared to post-hoc using the Student Newman levels test. The residual resin on the tooth surface after debonding was evaluated with adhesive remnant index. CLINICAL SIGNIFICANCE: The results revealed that in situations in which moisture contamination is critical there is distinct advantage in using hydrophilic primers.

Quantitative assessment of palatal bone thickness in an ethnic Indian population: a computed tomography study.

CONTEXT: Variations in palatal bone thickness (PBT) at various locations have caused considerable problems when using these sites for anchorage purposes. AIMS: To find the comparative thickness of the palatal bone at different locations and to validate its morphology for anchorage purposes using mini-implants (MI). SETTINGS AND DESIGN: This investigation was undertaken to compare the mean PBT and level of significance of differences between male and female subjects and between two different age-groups. MATERIALS AND METHODS: The computed tomography (CT) data for 60 patients (30 males and 30 females) in two different age-groups (group A: 15-24 years; group B: 25-35 years) were imported into CAD-based medical software, (MIMICS; Materialise, Belgium) for multiplanar reconstruction. The measurements were made in two planes- transverse and sagittal-and at different positions in each of the planes. STATISTICAL ANALYSIS: The mean and standard deviations of the PBT at different points were calculated. The Student's t-test and Mann-Whitney U test were used for comparisons between the groups. RESULTS: Significant variations were observed in the thickness of the palatal bone for both groups tested, with the anterior region at 4 mm behind the incisive papilla showing the maximum thickness. CONCLUSIONS: Despite the palatal bone being thickest in the mid-palatal suture (MPS) region, this is not the ideal site for anchorage purposes due to inadequate calcification and interposition of connective tissue, especially in young growing children. So, the alternate optimum position is the paramedian region, 3 mm lateral to the MPS and 4 mm from the incisive foramen (IF).