Effect of prophylactic instrumentation on surface roughness of tooth-colored restorative material: An in vitro study.

AIM: To compare and evaluate the surface characteristics of different restorative materials used for restoration of cervical defects when subjected to periodontal prophylactic instrumentation techniques. MATERIALS AND METHODOLOGY: Sixty box-shaped cavities were prepared on the labial surface of decoronated permanent maxillary anterior teeth which were randomly divided into two groups (n = 30) based on the instrumentation technique Group I: Manual instrumentation using curettes and Group II: Ultrasonic instrumentation. The samples were further divided into three subgroups based on restorative material subgroups I V and II V-restored with Vitremer, subgroups I F and II F-restored with Filtek Z 250 XT and subgroups I D and II D-restored with Dyract flow, respectively. After finishing and polishing, the samples were subjected to surface profilometry analysis for determining the surface roughness values (Ra). Thereafter, the restored surfaces of all the samples in different subgroups were subjected to prophylactic instrumentation with Gracey's curettes (Group I) and ultrasonic scalers (Group II). Ra values were recorded again after prophylactic instrumentation and after polishing. The data thus obtained were subjected to the statistical analysis using the independent t-test and one-way ANOVA (p<0.05). RESULTS: Ra values were significantly higher for both manual and ultrasonic prophylaxis compared to preprophylaxis and postpolishing in all the three restorative materials. Ultrasonic scaling produced significantly higher Ra for subgroup V as compared to subgroup F and subgroup D, whereas the difference between the materials was not significant for manual scaling. CONCLUSION: Manual prophylaxis resulted in significant reduction in surface roughness of all the three restorative materials while ultrasonic prophylaxis resulted in significant reduction for Vitremer only. Polishing after scaling significantly reduced the effect of both manual and ultrasonic prophylaxis on surface roughness.

Effect of Different Finishing and Polishing Systems on the Surface Roughness of Resin Composite and Enamel: An In vitro Profilometric and Scanning Electron Microscopy Study.

AIM: The aim is to compare and evaluate the different finishing and polishing systems for the change in surface roughness of resin composites and enamel. MATERIALS AND METHODS: To conduct the study, 30 extracted human maxillary central incisors were selected, decoronated, and molded in self-cure acrylic molds. A box-shaped cavity of dimensions 3 mm × 3 mm × 2 mm was prepared in all the teeth. A nanohybrid composite resin (Filtek Z250) was then used to restore the prepared cavities. Thirty samples were divided into two groups, control group (Group A, n = 10) and experimental group (Group B, n = 20). The samples in Group A were cured through the Mylar matrix. The experimental group, i.e., Group B was divided into two subgroups, i.e., Subgroup BX, n = 10 in which Sof-Lex polishing system was used for polishing the tooth surface and Subgroup BF, n = 10 in which Shofu composite polishing system was used. The mean surface roughness (Ra in µm) of the composite restoration as well as for the enamel surface of all the samples before and after polishing was measured with a contact profilometer, and the values were correlated with scanning electron microscopy. RESULTS: The statistical analysis was carried out using paired t-test. The results exhibited a significant decrease in the surface roughness of the resin composite and enamel surface irrespective of the finishing and polishing system used. The mean surface roughness values demonstrated by Mylar matrix was the lowest followed by Sof-Lex polishing system. Shofu polishing system demonstrated the highest surface roughness values. CONCLUSION: Finishing and polishing of composite restoration can achieve a surface roughness similar to that of enamel. Involvement of marginal enamel in finishing and polishing procedures carried out for composite restoration results in smoother enamel surface.

Comparison of fluoride ion release and alkalizing potential of a new bulk-fill alkasite.

AIM: This study was conducted to evaluate and compare fluoride ion release by Cention-N (self-cure and light-cure) and conventional glass-ionomer cement (GIC) at different pH and time intervals. METHODOLOGY: Cavities of similar dimensions were prepared in mandibular molars and restored with Cention-N (by self-cure and light-cure techniques) and GIC. Samples were stored in deionized water, and the cumulative fluoride ion release and change in pH were assessed utilizing spectrophotometer and pH meter, respectively, at the end of 7 days, 14 days, and 21 days. The data thus obtained were statistically analyzed. RESULTS: All the tested materials released fluoride ions in both acidic and neutral pH at all time intervals, and the fluoride ion release was significantly higher (<0.05) in acidic pH as compared to neutral pH except in GIC. All the groups showed a statistically significant increase in pH in acidic medium, whereas no significant increase was observed in neutral medium. CONCLUSIONS: Cention-N (self-cure) has the highest fluoride ion release and alkalizing potential in acidic pH as compared to Cention-N (light-cure) and GIC.

In vitro evaluation of the contact angle formed between AH Plus, Hybrid Root Seal and mineral trioxide aggregate Plus sealer with dentin and gutta-percha.

AIM: The purpose of this study was evaluation and comparison of the contact angle of new root canal sealers - Hybrid Root Seal, mineral trioxide aggregate (MTA) Plus, and the conventional AH Plus sealer with dentin and gutta-percha. MATERIALS AND METHODS: Two groups (Group D - dentin and Group G - gutta-percha) of 18 samples each were further randomly divided into 3 subgroups based on the type of sealer used, that is, AH Plus, Hybrid Root Seal, and MTA Plus. Contact angle measurement device (Phoenix 300) was used to measure the contact angle of the sealers on both dentin and gutta-percha. The results thus obtained were analyzed using one-way analysis of variance and Student's t-test. RESULTS: MTA Plus recorded significantly higher values of contact angle on both the substrates, that is, dentin and gutta-percha when compared to AH Plus and Hybrid root canal sealer. The lowest value of contact angle in gutta-percha and dentin was shown by Hybrid root canal sealer and AH Plus, respectively. CONCLUSION: Both AH Plus and Hybrid Root Seal exhibited lower contact angle values, and hence, better wettability on both dentin and gutta-percha as compared to MTA Plus.

Evaluation of marginal sealing ability of self-adhesive flowable composite resin in Class II composite restoration: An in vitro study.

AIM: The aim of this study is to evaluate the marginal sealing ability of self-adhesive flowable composite resin when used as a liner in Class II composite restoration with and without aging. MATERIALS AND METHODS: A total of 120 standardized Class II tooth preparations with gingival margins 1 mm coronal and apical to cementenamel junction (CEJ) were prepared on 60 extracted permanent mandibular molars and were randomly divided into eight equal Groups: Group 1: cavities coronal to CEJ and restored with Dyad flow liner + Herculite ultra, Group 2: same as Group 1 but cavities margins apical to CEJ, Group 5: cavities coronal to CEJ and restored with only Herculite ultra, and Group 6: same as Group 5 but cavities apical to CEJ. Groups 3,4,7,8 were similar to Groups 1,2,5,6, respectively, but were aged for 6 months. After thermocycling, microleakage testing was done using 0.5% basic fuchsin dye. RESULT: At cervical level, Group 5 exhibited statistically lower (P = 0.006) microleakage than Group 6, and Group 1 showed lesser microleakage than Group 5 (P = 0.162). Group 2 exhibited significantly less microleakage than Group 6 (P = 0.002). Increased microleakage was observed in aging Groups; however, the difference with nonaging Groups was not statistically significant (P > 0.005). CONCLUSION: Margins of the cavity in cementum can be better sealed by placing self-adhesive liner and is not affected by aging.

Effect of phytic acid, ethylenediaminetetraacetic acid, and chitosan solutions on microhardness of the human radicular dentin.

AIM: The purpose of this study was to evaluate the effect of phytic acid, ethylenediaminetetraacetic acid (EDTA), and chitosan solutions on the microhardness of human radicular dentin. MATERIALS AND METHODS: Thirty dentin specimens were randomly divided into three groups of 10 specimens each according to the irrigant used: G1 - 1% phytic acid, G2 - 17% EDTA, and G3 - 0.2% chitosan. A standardized volume of each chelating solution was used for 3 min. Dentin microhardness was measured before and after application at the cervical, middle, and apical levels with a Vickers indenter under a 200-g load and a 10-s dwell time. The results were analyzed using one-way analysis of variance (ANOVA) and Student's t test. RESULTS: Microhardness of the radicular dentin varied at the cervical, middle, and apical levels. EDTA had the greatest overall effect, causing a sharp percentage reduction in dentin microhardness with a significant difference from phytic acid and chitosan (P = 0.002). However, phytic acid and chitosan differed insignificantly from each other (P = 0.887). CONCLUSION: All tested chelating solutions reduced microhardness of the radicular dentin layer at all the levels. However, reduction was least at the apical level. EDTA caused more reduction in dentin microhardness than chitosan while phytic acid reduced the least.

Evaluation of effect of addition of 2% chlorhexidine on the sealing ability of Biodentine: An in vitro study.

AIM: To evaluate the effect of the addition of 2% chlorhexidine on the sealing ability of Biodentine. MATERIALS AND METHODS: Forty-six extracted human premolar teeth with single canal and apical foramen were selected, cleaned, and decoronated to standardize the length of 17 mm. Canals were prepared using ProTaper rotary files till size F4. The samples were divided into 2 experimental groups of 20 samples each on the basis of absence/presence of 2% chlorhexidine in liquid: Group BM = Biodentine mixed with the provided liquid, Group BC = Biodentine mixed with 2% chlorhexidine in provided liquid. Three samples, each were assigned to control groups: Group BP (positive control) = No root end filling was placed, Group BN (negative control) = Root ends were filled as in Group BM, and entire external surface was coated with sticky wax. The samples were then evaluated for the apical sealing using fluid filtration method. RESULTS: Results were analyzed using Student's t-test (P ≤ 0.05). Group BC showed the better sealing ability (3.06) as compared to Group BM (3.85). However, the difference was statistically insignificant (P > 0.05). CONCLUSION: Addition of 2% chlorhexidine to the liquid enhanced the sealing ability of Biodentine.

Comparative evaluation of microleakage in Class II restorations using open vs. closed centripetal build-up techniques with different lining materials.

BACKGROUND: Evaluation of microleakage is important for assessing the success of new restorative materials and methods. AIM AND OBJECTIVES: Comparative evaluation of microleakage in Class II restorations using open vs. closed centripetal build-up techniques with different lining materials. MATERIALS AND METHODS: Standardized mesi-occlusal (MO) and distoocclusal (DO) Class II tooth preparations were preparedon 53 molars and samples were randomly divided into six experimental groups and one control group for restorations. Group 1: Open-Sandwich technique (OST) with flowable composite at the gingival seat. Group 2: OST with resin-modified glass ionomer cement (RMGIC) at the gingival seat. Group 3: Closed-Sandwich technique (CST) with flowable composite at the pulpal floor and axial wall. Group 4: CST with RMGIC at the pulpal floor and axial wall. Group 5: OST with flowable composite at the pulpal floor, axial wall, and gingival seat. Group 6: OST with RMGIC at the pulpal floor, axial wall, and gingival seat. Group 7: Control - no lining material, centripetal technique only. After restorations and thermocycling, apices were sealed and samples were immersed in 0.5% basic fuchsin dye. Sectioning was followed by stereomicroscopic evaluation. RESULTS: Results were analyzed using Post Hoc Bonferroni test (statistics is not a form of tabulation). Cervical scores of control were more than the exprimental groups (P < 0.05). Less microleakage was observed in CST than OST in all experimental groups (P < 0.05). However, insignificant differences were observed among occlusal scores of different groups (P > 0.05). CONCLUSION: Class II composite restorations with centripetal build-up alone or when placed with CST reduces the cervical microleakage when compared to OST.

Comparing gray and white mineral trioxide aggregate as a repair material for furcation perforation: an in vitro dye extraction study.

INTRODUCTION: Furcation perforation can have a negative impact on the prognosis of the affected tooth by compromising the attached apparatus. Hence these perforations require immediate repair. A variety of materials have been suggested for repair, of that MTA is the most promising material. The purpose of this study was to compare the ability of Gray and White MTA to seal furcation perforations using a dye extraction method under spectrophotometer. MATERIALS AND METHODS: A total of 60 permanent mandibular molars were randomly divided into four experimental groups of 15 samples each as follows: Group A: Perforation repaired with White MTA. Group B: Perforation repaired with Gray MTA. Group C: Perforation left unsealed (positive). Group D: without perforation (negative). Dye extraction was performed using full concentration nitric acid. Dye absorbance was measured at 550 nm using spectrophotometer. The data analyzed using one-way-Anova Ratio and Unpaired t-test showing statistically significance difference among the groups. RESULT: It was seen that Group D samples without perforation showed least absorbance followed by Group A (perforation repaired with White MTA) and Group B (perforation repaired with Gray MTA). Group C (perforation left unsealed) showed highest absorbance. CONCLUSION: The White and Gray Mineral Trioxide Aggregate performed similarly as a furcation perforation repair material. There was no significant difference between the Gray MTA and White MTA.

Endodontic management of permanent mandibular left first molar with six root canals.

The endodontic treatment of a mandibular molar with aberrant canal configuration can be diagnostically and clinically challenging. This case report presents the treatment of a mandibular first molar with six root canals, of which three canals were located in the mesial root and three in distal root. Third canals were found between the two main root canals. This case presents a rare anatomic configuration and points to the importance of expecting and searching for additional canals.