scholarly journals MBCL-15. IMPACT OF MOLECULAR SUBGROUPS ON OUTCOMES FOLLOWING RADIATION TREATMENT RANDOMIZATIONS FOR AVERAGE RISK MEDULLOBLASTOMA: A PLANNED ANALYSIS OF CHILDREN’S ONCOLOGY GROUP (COG) ACNS0331

2020 ◽  
Vol 22 (Supplement_3) ◽  
pp. iii391-iii391
Author(s):  
Jeff Michalski ◽  
Paul Northcott ◽  
Yimei Li ◽  
Catherine Billups ◽  
Kyle Smith ◽  
...  
Keyword(s):  
Radiation Treatment ◽  
Standard Dose ◽  
Molecular Classification ◽  
Young Group ◽  
Average Risk ◽  
Molecular Subgroup ◽  
Radiation Boost ◽  
Group 4 ◽  
Significant Difference ◽  
Group 3

Abstract The COG conducted a randomized trial for average-risk medulloblastoma (AR-MB). Patients age 3–21 years were randomized to a radiation boost to the whole posterior fossa (PFRT) or an involved field volume (IFRT) after receiving CSI. Patients age 3–7 years were also randomized to standard dose CSI (23.4Gy, SDCSI) or low dose CSI (18Gy, LDCSI). 464 evaluable patients were available to compare PFRT vs. IFRT and 226 for SDCSI vs. LDCSI. 380 cases had sufficient tissue for DNA methylation-based molecular classification: 362 confirmed medulloblastoma; 6 non-medulloblastoma; 12 inconclusive. Molecular subgrouping confirmed the following representation amongst the evaluable cohort: 156 Group 4 (43.1%), 76 Group 3 (21.0%), 66 SHH (18.2%), 64 WNT (17.7%). Five-year event-free survival (EFS) estimates were 82.5±2.7% and 80.5±2.7% for IFRT and PFRT, respectively (p=0.44). Five-year EFS estimates were 71.4±4.4% and 82.9±3.7% for LDCSI and SDCSI, respectively (p=0.028). EFS distributions differed significantly by subgroup (p<0.0001). Group 3 had the worst outcome, while WNT had the best outcome. There was a significant difference in EFS by RT group among SHH patients; SHH patients receiving IFRT arm had better EFS compared to PFRT (p=0.018). There was a significant difference in EFS distributions by CSI group in Group 4 patients; young Group 4 patients treated with SDCSI had better EFS compared to LDCSI (p=0.047). As previously reported, IFRT is noninferior to PFRT in all patients with AR-MB but LDCSI is worse than SDCSI in younger children. Significant differences in outcome by study randomization and molecular subgroup are observed.

scholarly journals IMG-19. RADIOMICS AND SUPERVISED DEEP LEARNING TO PREDICT MOLECULAR SUBGROUPS IN MEDULLOBLASTOMA BASED ON WHOLE TUMOR VOLUME LABELING: A SINGLE CENTER MULTIPARAMETRIC MR ANALYSIS

2020 ◽  
Vol 22 (Supplement_3) ◽  
pp. iii358-iii359
Author(s):  
Ioan Paul Voicu ◽  
Piero Chiacchiaretta ◽  
Massimo Caulo ◽  
Evelina Miele ◽  
Alessia Carboni ◽  
...  
Keyword(s):  
Random Forest ◽  
Intraclass Correlation ◽  
Major Axis ◽  
Molecular Classification ◽  
Molecular Subgroups ◽  
Molecular Subgroup ◽  
First Order ◽  
Group 4 ◽  
Contrast Enhanced ◽  
Group 3

Abstract PURPOSE Medulloblastoma (MB) is a complex pathology. Four molecular subgroups have been unveiled (Wingless-WNT, Sonic Hedgehog-SHH, Group 3-G3 and Group 4-G4), characterized by significant differences in patient clinical outcome. We investigated the utility of a radiomic analysis to predict molecular subgroups in patients with MB. MATERIALS AND METHODS We retrospectively evaluated 42 patients with histological diagnosis of MB, known molecular subgroup, and diagnostic MRI scan performed in our Institution on a 3 Tesla magnet. For each patient, FLAIR, ADC, T2 and contrast-enhanced MPRAGE sequences were analysed. Solid tumor volumes were segmented semiautomatically. 107 features were extracted for each sequence (Pyradiomics, Python). Features were tested for stability against labelling variations, selecting those presenting Intraclass Correlation Coefficient (ICC)>0.9 across all labelling variations and all sequences. Among the remaining features, relevant features were selected with an all-relevant wrapper algorithm (Boruta, R). Remaining features were used to predict MB subgroup with a Random Forest algorithm(R). The most relevant features were ranked based on Gini index (R). RESULTS 83/107 features presented ICC >0.9 for all sequences. Boruta selected 10 features. Classification analysis yielded an out-of-bag (OOB) error rate of 0.6%, (99.4% accuracy). The most relevant features for classification were “simple” first-order features such as volume, major axis or shape. CONCLUSION This radiomic study yielded robust features, which showed high accuracy in predicting the molecular MB subgroups. Random forest algorithms are ideal for multiclass classification (eg. MB subgroups) and are intrinsically suited against overfitting. The most relevant for molecular classification were first-order features.

scholarly journals LINC-15. OUTCOME OF CHINESE CHILDREN WITH MEDULLOBLASTOMA: A MULTI-CENTER EXPERIENCE WITH RISK-ADAPTED THERAPY

2020 ◽  
Vol 22 (Supplement_3) ◽  
pp. iii381-iii381
Author(s):  
Xiaofei Sun ◽  
Anthony Pak-Yin Liu ◽  
Qunying Yang ◽  
Jian Wang ◽  
Shaoxiong Wu ◽  
...  
Keyword(s):  
High Risk ◽  
Residual Tumor ◽  
Large Cell ◽  
High Dose ◽  
Average Risk ◽  
Group 4 ◽  
High Risk Disease ◽  
Significant Difference ◽  
Oncology Care ◽  
Group 3

Abstract BACKGROUND Medulloblastoma is the commonest brain tumor in young children but literature on Chinese is scarce. We hereby present the outcome of children with medulloblastoma managed according to a risk- and age-stratified guideline from ten institutions across China. METHODS Patients <18 years of age diagnosed with medulloblastoma between January 2016 and April 2019 were reviewed. Patients ≥3 years, stratified into average-risk (≤1.5cm2 residual tumor, non-metastatic, non-anaplastic histology) and high-risk (others) groups, were treated with risk-adapted craniospinal irradiation (average-risk: 23.4Gy, high-risk: 36Gy), tumor boost, and chemotherapy (lomustine/cisplatin/vincristine). Patients <3 years (considered high-risk, other than patients with localized and desmoplastic/nodular histology) received chemotherapy (cyclophosphamide/vincristine, high-dose methotrexate, carboplatin/etoposide) with/without delayed irradiation. RESULTS 112 patients were included with a median age at diagnosis of 6.5 years (range: 0.5–16.7). 16 patients (14.3%) had residual tumor >1.5cm2 and 36 (32%) had metastasis. Available data on histological subtype (n=87) were classic in 56 (64%), desmoplastic/nodular or extensive nodularity in 23 (26%), and large cell/anaplastic in 8 (9%). Molecular subgrouping (n=55) assigned tumors as WNT-activated (n=8, 15%), SHH-activated (n=17, 31%), Group 3 (n=12, 22%) and Group 4 (n=18, 33%). Respective 2-year EFS/OS for patients ≥3 and <3 years were 86.0±4.0%/96.4±2.1% and 57.8±12.6%/81.4±9.8% (EFS/OS p<0.001/p=0.009). Significant difference in outcome was also observed between patients with average-risk and high-risk disease (EFS/OS p=0.006/p=0.018). CONCLUSION We demonstrated feasibility in protocolizing the inter-disciplinary treatment for medulloblastoma in China. This will serve as a prototype for the standardization of pediatric neuro-oncology care in the country.

In-vivo evaluation of the effect of cyanoacrylate on prosthetic vascular graft infection – does cyanoacrylate increase the severity of infection?

VASA ◽  
2020 ◽  
Vol 49 (4) ◽  
pp. 281-284
Author(s):  
Atıf Yolgosteren ◽  
Gencehan Kumtepe ◽  
Melda Payaslioglu ◽  
Cuneyt Ozakin
Keyword(s):  
Vascular Graft ◽  
Graft Infection ◽  
Vascular Graft Infection ◽  
Group 4 ◽  
Significant Difference ◽  
Group 3 ◽  
Group 2 ◽  
Prosthetic Vascular Graft Infection ◽  
Group 1

Summary. Background: Prosthetic vascular graft infection (PVGI) is a complication with high mortality. Cyanoacrylate (CA) is an adhesive which has been used in a number of surgical procedures. In this in-vivo study, we aimed to evaluate the relationship between PVGI and CA. Materials and methods: Thirty-two rats were equally divided into four groups. Pouch was formed on back of rats until deep fascia. In group 1, vascular graft with polyethyleneterephthalate (PET) was placed into pouch. In group 2, MRSA strain with a density of 1 ml 0.5 MacFarland was injected into pouch. In group 3, 1 cm 2 vascular graft with PET piece was placed into pouch and MRSA strain with a density of 1 ml 0.5 MacFarland was injected. In group 4, 1 cm 2 vascular graft with PET piece impregnated with N-butyl cyanoacrylate-based adhesive was placed and MRSA strain with a density of 1 ml 0.5 MacFarland was injected. All rats were scarified in 96th hour, culture samples were taken where intervention was performed and were evaluated microbiologically. Bacteria reproducing in each group were numerically evaluated based on colony-forming unit (CFU/ml) and compared by taking their average. Results: MRSA reproduction of 0 CFU/ml in group 1, of 1410 CFU/ml in group 2, of 180 200 CFU/ml in group 3 and of 625 300 CFU/ml in group 4 was present. A statistically significant difference was present between group 1 and group 4 (p < 0.01), between group 2 and group 4 (p < 0.01), between group 3 and group 4 (p < 0.05). In terms of reproduction, no statistically significant difference was found in group 1, group 2, group 3 in themselves. Conclusions: We observed that the rate of infection increased in the cyanoacyrylate group where cyanoacrylate was used. We think that surgeon should be more careful in using CA in vascular surgery.

scholarly journals MBRS-47. RAPID MOLECULAR SUBGROUPING OF MEDULLOBLASTOMA BASED ON DNA METHYLATION BY NANOPORE SEQUENCING

2020 ◽  
Vol 22 (Supplement_3) ◽  
pp. iii406-iii406
Author(s):  
Julien Masliah-Planchon ◽  
Elodie Girard ◽  
Philipp Euskirchen ◽  
Christine Bourneix ◽  
Delphine Lequin ◽  
...  
Keyword(s):  
Dna Methylation ◽  
Single Molecule ◽  
Nanopore Sequencing ◽  
Molecular Subgroup ◽  
Group Assignment ◽  
Group 4 ◽  
Methylation Assay ◽  
Tumor Group ◽  
Long Read ◽  
Group 3

Abstract Medulloblastoma (MB) can be classified into four molecular subgroups (WNT group, SHH group, group 3, and group 4). The gold standard of assignment of molecular subgroup through DNA methylation profiling uses Illumina EPIC array. However, this tool has some limitation in terms of cost and timing, in order to get the results soon enough for clinical use. We present an alternative DNA methylation assay based on nanopore sequencing efficient for rapid, cheaper, and reliable subgrouping of clinical MB samples. Low-depth whole genome with long-read single-molecule nanopore sequencing was used to simultaneously assess copy number profile and MB subgrouping based on DNA methylation. The DNA methylation data generated by Nanopore sequencing were compared to a publicly available reference cohort comprising over 2,800 brain tumors including the four subgroups of MB (Capper et al. Nature; 2018) to generate a score that estimates a confidence with a tumor group assignment. Among the 24 MB analyzed with nanopore sequencing (six WNT, nine SHH, five group 3, and four group 4), all of them were classified in the appropriate subgroup established by expression-based Nanostring subgrouping. In addition to the subgrouping, we also examine the genomic profile. Furthermore, all previously identified clinically relevant genomic rearrangements (mostly MYC and MYCN amplifications) were also detected with our assay. In conclusion, we are confirming the full reliability of nanopore sequencing as a novel rapid and cheap assay for methylation-based MB subgrouping. We now plan to implement this technology to other embryonal tumors of the central nervous system.

scholarly journals Microleakage beneath Ceramic and Metal Brackets Bonded with a Conventional and an Antibacterial Adhesive System

2006 ◽  
Vol 76 (6) ◽  
pp. 1028-1034 ◽  
Author(s):  
Neslihan Arhun ◽  
Ayca Arman ◽  
Sevi Burçak Çehreli ◽  
Serdar Arıkan ◽  
Erdem Karabulut ◽  
...  
Keyword(s):  
Adhesive System ◽  
White Spot Lesions ◽  
Adhesive Interface ◽  
Group 4 ◽  
Significant Difference ◽  
Ceramic Brackets ◽  
Group 3 ◽  
Group 2 ◽  
Ceramic Bracket ◽  
Nail Varnish

Abstract Objective: To assess microleakage of a tooth-adhesive-bracket complex when metal or ceramic brackets were bonded with a conventional and an antibacterial self-etching adhesive. Materials and Methods: Forty freshly extracted human premolars were randomly assigned to four equal groups and received the following treatments: group 1 = Transbond XT + metal bracket, group 2 = Transbond XT + ceramic bracket, group 3 = Clearfil Protect Bond + ceramic bracket, and group 4 = Clearfil Protect Bond + metal bracket. After photopolymerization, the teeth were kept in distilled water for 1 month and thereafter subjected to thermal cycling (500 cycles). Specimens were further sealed with nail varnish, stained with 0.5% basic fuchsin for 24 hours, sectioned and examined under a stereomicroscope, and scored for marginal microleakage for the adhesive-tooth and bracket-adhesive interfaces from incisal and gingival margins. Statistical analysis was accomplished by Kruskal-Wallis test and Mann-Whitney U-test with Bonferroni correction. Results: All groups demonstrated microleakage between the adhesive-enamel and bracket-adhesive interfaces. A significant difference was observed among all groups (P &lt; .05) for the microleakage between the bracket-adhesive interface. Metal brackets exhibited significantly more microleakage than did ceramic brackets between the bracket-adhesive interface with either of the adhesives. Clearfil Protect Bond exhibited results similar to Transbond XT. Clearfil Protect Bond may be a choice of adhesive in bracket bonding because of its antibacterial activity and similar microleakage results with the orthodontic adhesive. Conclusions: Metal brackets cause more leakage between an adhesive-bracket interface, which may lead to lower clinical shear bond strength and white-spot lesions.

scholarly journals Comparative evaluation of postoperative pain intensity after single-visit and multiple-visit retreatment cases: a prospective randomized clinical trial

2018 ◽  
Vol 21 (1) ◽  
pp. 26 ◽  
Author(s):  
Hatice Miray Uyan ◽  
Keziban Olcay ◽  
Mutlu Özcan
Keyword(s):  
Postoperative Pain ◽  
Repeated Measures ◽  
Control Group ◽  
Periapical Lesions ◽  
Single Visit ◽  
Group 4 ◽  
Multiple Visit ◽  
Significant Difference ◽  
Group 3 ◽  
Group 2

<p><strong>Objective:</strong> This study was designed to evaluate postoperative pain after endodontic retreatment. <strong>Material and Methods:</strong> Asymptomatic, multi-rooted molar &amp; premolar teeth requiring retreatment with 2–5 mm periapical lesions were included. Seventy-eight teeth were randomly placed in four groups (n=20): single-visit (control, group 1), Ledermix (group 2), metronidazole, ciprofloxacin, minocycline mixture (group 3), calcium hydroxide (group 4). The postoperative pain was recorded using a VAS at 6, 12, 24, and 48 h after retreatment. Statistical evaluation was performed using Two-Way Repeated Measures ANOVA and Tukey test. <strong>Results:</strong> Mild pain occurred in 67.5%, moderate in 30%, and flare-ups in 2.5%, and there was a significant difference between the groups (p&lt;0.01). Significantly lower postoperative pain was observed in TAP and CaOH<sub>2 </sub>groups(p&lt;0.05). In the 6, 12, and 24 h intervals, there was a significant difference in the pain levels (p&lt;0.05). <strong>Conclusion:</strong> TAP and CaOH<sub>2</sub> are effective for reducing postoperative pain after retreatment.</p><p><strong>Keywords</strong></p><p>Intracanal medicaments; Multiple-visit; Postoperative pain; Retreatment; Single-visit.</p>

scholarly journals Microleakage under Ceramic and Metallic Brackets Bonded with Resin-Modified Glass Ionomer

2009 ◽  
Vol 79 (1) ◽  
pp. 138-143 ◽  
Author(s):  
Sabri Ilhan Ramoglu ◽  
Tancan Uysal ◽  
Mustafa Ulker ◽  
Huseyin Ertas
Keyword(s):  
Glass Ionomer ◽  
Bonferroni Correction ◽  
Adhesive Systems ◽  
Dye Penetration ◽  
Group 4 ◽  
System A ◽  
Significant Difference ◽  
Resin Modified Glass Ionomer ◽  
Ceramic Brackets ◽  
Group 3

Abstract Objective: To test the null hypothesis that there is no significant difference between the microleakage of adhesive interferences at the occlusal and gingival margins of both ceramic and metallic brackets bonded with light-cured resin-modified glass ionomer and a conventional adhesive. Materials and Methods: Sixty freshly extracted human maxillary premolar teeth were randomly divided into four groups of 15 teeth each. Metal and ceramic brackets were bonded to groups 1 and 2 with resin-modified glass ionomer adhesive (RMGIA). Metal and ceramic brackets were bonded to group 3 and group 4 with a conventional adhesive (CA) system. A dye-penetration method was used for microleakage evaluation. Microleakage from the occlusal and gingival margins was determined by a stereomicroscope for the enamel-adhesive and bracket-adhesive interfaces. Statistical analysis was performed using the Kruskal-Wallis test and the Mann-Whitney U-test with a Bonferroni correction. Results: The gingival side of all groups exhibited higher microleakage scores compared with the occlusal side for both adhesive interfaces. All bracket and adhesive combinations displayed statistically significant differences in microleakage between the enamel-adhesive and adhesive-bracket interfaces at the occlusal and gingival sides of the brackets (P &lt; .001). When the adhesive systems were compared, the RMGIA showed more microleakage than the CA between the different interfaces. Conclusions: The hypothesis is rejected. RMGIA results in more microleakage between enamel-adhesive interfaces.

In vivosilymarin’s antioxidant and anti-apoptotic effects on photodynamic therapy’s responsiveness

2017 ◽  
Vol 21 (03) ◽  
pp. 189-197 ◽  
Author(s):  
Vlad Dionisie ◽  
Simona Clichici ◽  
Rodica M. Ion ◽  
Oana O. Danila ◽  
Remus Moldovan ◽  
...  
Keyword(s):  
Photodynamic Therapy ◽  
Reactive Oxygen Species Generation ◽  
Group 4 ◽  
Significant Difference ◽  
Anti Oxidant ◽  
Group 3 ◽  
Group 5 ◽  
Group 2 ◽  
Apoptotic Effects ◽  
Oxidant Effect

Several studies have shown that some anti-oxidant natural compounds in combination with photodynamic therapy (PDT) can enhance the effectiveness of treatment. The aim of this study is to evaluate the effect of silymarin (SIL) in combination with 5,10,15,20-tetra-sulphonato-phenyl-porphyrin (TSPP) based photodynamic therapy, on experimental tumors. 30 Wistar rats with Walker carcinosarcoma, were divided into 6 groups: group 0 (control) — control, untreated group; group 1 (TSPP) — one dose of TSPP; group 2 (SIL) — silymarin; group 3 (PDT) — TSPP and irradiation 24 h after; group 4 (SIL[Formula: see text]PDT) — silymarin, TSPP and irradiation 24 h after; group 5 (SIL[Formula: see text]IR) and group 6 (IR) — irradiation and in addition, group 5 received SIL. Silymarin administered before photodynamic therapy decreased the lipid peroxidation ([Formula: see text] < 0.05) and modulated the antioxidant defense in tumor treated with PDT and silymarin suggesting that silymarin administration along with photodynamic therapy has an anti-oxidant effect. The caspase — 8 level and -3 activity increased in PDT and PDT [Formula: see text] SIL groups compared to the control; between the two groups there was a significant difference in term of apoptosis in favor to PDT. In conclusion, silymarin administration inhibited the reactive oxygen species generation and reduced the tumoral cells’ apoptosis, suggesting that natural compound administered before photodynamic therapy did not improve the therapy’s effect.

Efficacy of Double Manual Cleaning Versus Automated Cleaning for Removal of Biofilm of Hinged Surgical Instruments

2020 ◽  
Vol 41 (S1) ◽  
pp. s518-s519
Author(s):  
Dayane Costa ◽  
Roel Castillo ◽  
Lillian Kelly Lopes ◽  
Anaclara Tipple ◽  
Honghua Hu ◽  
...  
Keyword(s):  
Protein Level ◽  
Positive Control ◽  
Surgical Instruments ◽  
Microbial Load ◽  
Positive Control Group ◽  
Control Group ◽  
Group 4 ◽  
Significant Difference ◽  
Group 3 ◽  
Group 2

Objectives: To evaluate the efficacy of double manual cleaning (DMC) with enzymatic followed by alkaline detergent for removing biofilm on hinged surgical instruments compared to automated cleaning by the washer-disinfector. Methods: Biofilm of Staphylococcus aureus (ATCC 25923) was formed in vitro on hemostatic forceps (Fig. 1). Biofilm-covered forceps were rinsed in distilled water and subjected to one of the following cleaning regimes (n = 5 forceps each): Group 1 forceps were soaked in sterile water for 5 minutes. Group 2-DMC forceps were soaked in enzymatic detergent, brushed 5 times on each face, rinsed with filtrated water (0.2 µm), soaked in alkaline detergent, brushed 5 times each face, rinsed with filtrated water (0.2 µm), and dried with sterile cloth. For group 3-DMC plus hinge inner brushing (n = 5), the forceps were soaked in detergents and brushed as in group 2, including hinge inner brushing (2-mm lumen brush) (Fig. 1). In group 4 (automated cleaning in a washer/disinfector), forceps were prewashed, washed once, washed again, rinsed, thermally rinsed, and dried. After the treatments, forceps were evaluated for microbial load (counting of colony-forming units), residual protein (BCA protein assay kit), and biofilm (scanning electron microscopy). Results: There was no statistically significant differences between the microbial load and protein level contaminating the forceps subjected to DMC (group 2) and the positive control group. The DMC with hinge inner brushing group (group 3) and the automated cleaning group (group 4) demonstrated a significantly reduced microbial load: reduction averages of 2.8 log 10 (P = .038) and 7.6 log10 (P ≤ .001), respectively. The protein level remaining on the forceps also significantly decreased: 2.563 μg (P = .016) and 1,453 μg (P = .001), respectively, compared to the positive control group. There was no statistically significant difference between DMC with hinge inner brushing and automated cleaning (groups 3 and 4) for all of the tests performed. None of the cleaning methods completely removed biofilm and/or soil from the forceps hinge internal region (Fig. 1). Conclusions: Automated cleaning had the best efficacy for removing biofilm. However, DMC with hinge inner brushing was an acceptable alternative cleaning method for sterilizing service units with only manual cleaning available, as is the case in most low- and middle-income countries. Neither automated nor any manual cleaning regimes were able to completely remove biofilm and soil from the forceps hinged area, and the amount of protein left after automated and DMC plus hinge brushing was higher than the recommended. Cleaning is the most important step for the reprocessing of reusable medical devices; thus, efforts must be undertaken to improve cleaning in different social and economic realities and scenarios.Funding: This study was supported by Coordenação de Aperfeiçoamento de Pessoal de Nível Superior – CAPES.Disclosures: None

scholarly journals Effect of Different Finishing and Polishing Methods for Color Stability of the E-Max Dental Ceramics: In vitro Study

2021 ◽  
Vol 14 (4) ◽  
pp. 1508-1513
Author(s):  
Ibraheem F Alshiddi
Keyword(s):  
Surface Brightness ◽  
Color Stability ◽  
Color Measurement ◽  
Control Group ◽  
Group 4 ◽  
Significant Difference ◽  
Group 3 ◽  
Group 2 ◽  
Group 1

In order to assess the influence of finishing and polishing on the surface brightness and color stability of the ceramic veneer, fifty specimens were fabricated with 10 mm diameter and 2 mm thickness using IPS E-Max Ceramic. After glazing, 10 specimens were untouched as control group, and the other 40 specimens were abraded using 125µm diamond bur to create surface roughness. Forty specimens were divided into four groups (n=10), in group 1: specimens were finished using diamond point, in group 2 specimens’ surface was polished with a polishing kit, Group 3: Each specimen surface was polished with the polishing kit as in protocol 2 and was polished a polishing past and group 4 Each specimen was glazed by heating at 621℃ for 3 minutes followed by a temperature increase of 83℃/min up to 918℃ for 30 seconds. Color measurement was performed using spectrophotometer. Color stability data were analyzed using two-way ANOVA and Tukey’s HSD test (α=0.05). For Ra values, paired-samples t-tests were used to analyze the data and compare groups. The change in L and E showed a significant difference among the study groups; (group 1, group 2, group 3 and group 4) with respect to three variables L, a and b. A significant difference was noted when compared each group with the control; however, only group 2 showed a significant difference from group 4; the remaining groups demonstrated similar findings for all three variables. The study displayed a significant impact of the finishing and polishing technique on the surface brightness and color stability of ceramic restoration. However, it was evident that combination of two or three polishing techniques which includes polish kit and glaze enhances the surface finish and adds color stability by alternating the yellow – blue axis (increase in b) and red- green axis (decrease in a).

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