Intracanal placement of calcium hydroxide: a comparison of specially designed paste carrier technique with other techniques

Micro-computed tomography analysis of calcium hydroxide delivery efficacy in C-shaped canal system of mandibular second molars

BACKGROUND

Calcium hydroxide [Ca(OH)2] is widely accepted as a biocompatible interappointment intracanal medicament. This study aimed to analyze the efficacy of Ca(OH)2 placement into the C-shaped canal system of mandibular second molars using the syringe method with and without lentulo spiral utilizing micro-computed tomography (micro-CT).

METHODS

Twenty-four extracted mandibular second molars were instrumented and classified into C-shaped floors (n = 12) and non-C-shaped floors (n = 12). Both groups were placed with Ca(OH)2 using the syringe system, then all teeth were scanned and cleaned, and placed with Ca(OH)2 again but with the syringe system followed by lentulo spiral and rescanned. The specimens were scanned using micro-CT to analyze the volume, volume percentage, uncontacted surface area, and uncontacted surface area percentage of Ca(OH)2 with the two delivery methods in the entire canal and at the apical 4 mm of the canal. Mann-Whitney test and Wilcoxon signed-rank test were used to determine the statistical differences among the groups.

RESULTS

Syringe administration used in conjunction with lentulo spiral presented lower uncontacted surface area, a lower percentage of uncontacted surface area, larger volume, and a higher percentage of volume than syringe without lentulo spiral (P < 0.05). There was no significant difference between the C-shaped floor group and the non-C-shaped floor group (P > 0.05) in the Ca(OH)2 uncontacted surface area, volume, and percentages at different regions of canals and among different delivery techniques groups.

CONCLUSIONS

The lentulo spiral and syringe technique combination can increase the volume and contacted surface area of Ca(OH)2 in the C-shaped canal system of mandibular second molars.

The efficacy of EndoActivator, passive ultrasonic irrigation, and Ultra X in removing calcium hydroxide from root canals: an in-vitro study

Background

This study aimed to compare the efficacy of EndoActivator, passive ultrasonic irrigation, and Ultra X in removing calcium hydroxide from the artificial grooves in root canal walls.

Methods

The root canals of 50 extracted human maxillary incisors were instrumented by using the ProTaper rotary system up to #F4 (size 40/0.06 ProTaper) and the teeth were split longitudinally. Lateral grooves were created in the apical and coronal parts of one half and the middle part of the other half. Calcium hydroxide paste was applied to the grooves and the root halves were reassembled. After seven days, the calcium hydroxide was removed from the canal by using one of the EndoActivator, passive ultrasonic irrigation, and Ultra X devices; one group went without irrigation (control group). The CH remnants in the grooves were scored at 20× magnification. The data were analyzed by using the Kruskal–Wallis, Dunn’s post hoc, and Friedman tests. P < 0.05 was considered to be statistically significant.

Results

No statistically significant difference existed among the experimental groups at the coronal and middle grooves (P > 0.05). However, Ultra X was significantly more effective than passive ultrasonic irrigation at the apical grooves (P = 0.023).

Conclusion

Within the limitations of this study, Ultra X can be reported to remove the calcium hydroxide from the apical third more efficiently than passive ultrasonic irrigation.

Influence of Filling Material Remnants on the Diffusion of Hydroxyl Ions in Endodontically Retreated Teeth: An Ex Vivo Study

AIM

To assess the influence of remnants of filling material on hydroxyl ion diffusion from calcium hydroxide (CH) paste, measured by the pH value, in retreated teeth.

MATERIALS AND METHODS

A total of 120 single-rooted extracted teeth were prepared up to a size 35 hand file and filled. For retreatment, the specimens were divided into four groups (n = 20): ProTaper Universal Retreatment (PUR), PUR with additional instrumentation (PURA), Mtwo Retreatment (MTWR), and MTWR with additional instrumentation (MTWRA). Negative (NEG) and positive (POS) control groups were composed by 20 specimens each one. The specimens, except NEG, were filled with CH paste. The retreated groups were scanned using cone-beam computed tomography (CBCT) for analysis of filling remnants. The pH assessment was performed at the baseline, after seven, 21, 45, and 60 days of immersion in saline. Data were analyzed using Shapiro-Wilk and Levene's test, followed by a two-way analysis of variance (ANOVA) and Tukey's test.

RESULTS

Additional instrumentation (PURA and MTWRA) were superior regarding removal of the filling material (p <0.05); however, without significant difference (p >0.05). The mean pH value in all groups increased (p <0.05). After 60 days, no statistical difference was observed among POS and PURA; and MTWR and MTWRA. There was less diffusion of hydroxyl ions when the amount of remnants was greater than 59%.

CONCLUSION

Additional instrumentation improved the ability to remove filling material in both systems. All groups presented increasing pH; however, the higher the amount of remnants, the lower the diffusion of hydroxyl ions.

CLINICAL SIGNIFICANCE

The amount of remnants allows less diffusion of calcium hydroxyl ions. Thus, additional instrumentation improves the ability to remove these materials.

Assessment of Four Obturation Methods in Deciduous Teeth Using Digital Radiography: An In Vivo Study

Aim and objective

This study was carried out to comparatively assess the efficiency of four methods of obturation viz Lentulo spiral, Navi tip syringe, Bi directional spiral, and Past inject carrier in deciduous teeth using vista scan.

Materials and methods

A total sample of 100 primary root canals [4 groups of 25 canals each] with 2/3^rd of root length were selected and randomly allocated into four different obturating techniques, i.e., Group I: Lentulo spiral, Group II: Navi tip syringe, Group III: Bi directional spiral, and Group IV: Past inject carrier. The quality of obturation [Coll and sadrain, 1996] and presence or absence of voids were evaluated by using Vista scan. The recorded data was statistically analyzed.

Results

The highest mean rank value of optimally filled canals was obtained by Group IV [58.00] followed by Group I [50.00] with no significant difference. The highest mean rank value of under filled canals and over filled canals were obtained by Group III and Group II, respectively, and these results were statistically significant. All the four obturation techniques showed presence of voids with no significant difference.

Conclusion

Both Lentulo spiral and Past inject carrier were equally efficient in attaining an optimally filled homogenous obturation in deciduous teeth.

How to cite this article

Raju SS, Reddy RE, Rani TS, et al. Assessment of Four Obturation Methods in Deciduous Teeth Using Digital Radiography: An In Vivo Study. Int J Clin Pediatr Dent 2022;15(S-1):S52-S56.

Antimicrobial Activity and pH of Calcium Hydroxide and Zinc Oxide Nanoparticles Intracanal Medication and Association with Chlorhexidine

AIM

To evaluate pH and antibacterial activity of pastes with calcium hydroxide [Ca(OH)2] and zinc oxide (ZnO) microparticles (micro) or nanoparticles (nano) and association with 0.4% chlorhexidine against Enterococcus faecalis.

MATERIALS AND METHODS

The following pastes were analyzed: Ca(OH)2/ZnO micro, (2) Ca(OH)2/ZnO nano, (3) Ca(OH)2/ ZnO micro + 0.4% chlorhexidine, (4) Ca(OH)2/ZnO nano + 0.4% chlorhexidine. Antibacterial activity against E. faecalis was evaluated by agar diffusion test. The direct contact test on planktonic cells of E. faecalis was performed for 30 and 60 seconds. Root canals from bovine teeth were filled with the pastes and pH was evaluated after 1, 7, 14, 21, 30 and 60 days. The data obtained were submitted to the statistical tests analysis of variance (ANOVA) and Tukey or Kruskal-Wallis and Dunn test, with a 5% significance level.

RESULTS

Calcium hydroxide and zinc oxide nano, and the pastes with 0.4% chlorhexidine were more effective in agar diffusion test. In the direct contact test, the pastes with chlorhexidine showed the highest effect after 30 seconds. All pastes eliminated E. faecalis after 60 seconds. All pastes promoted an increase in pH. The highest increase in pH was observed with nanoparticle medications after 1 and 7 days (p < 0.05). After this period, the pastes presented similar pH increase.

CONCLUSION

It was concluded that calcium hydroxide and zinc oxide nanoparticles promoted greater initial alkalinization. The antimicrobial activity of the pastes against E. faecalis is favored by the association with chlorhexidine.

CLINICAL SIGNIFICANCE

Although nanoparticles of calcium hydroxide and zinc oxide promoted antibacterial effect, the activity against E. faecalis is favored by association with chlorhexidine.