A Comparative Study of Ion Diffusion from Calcium Hydroxide with Various Herbal Pastes through Dentin

Microstructural modification of papaya tissue during calcium diffusion: Effects on macrostructure level

The microstructural changes in papaya tissue during calcium diffusion, the effect on drying kinetics and texture parameters were investigated. Calcium pretreatment was applied to papaya samples for 3 h, at a solution concentration of 1.5 g Ca(OH)2/100 mL H2O, and a solution temperature of 25 °C; subsequently, the samples were convectively dried at 70 °C, air flow of 1.5 m/s, and a relative humidity of 5 ± 2%. Calcium content was determined using the Inductively Coupled Plasma-Optical Emission Spectrometry (ICP-OES) technique, the microstructure of the samples was analyzed by High-Resolution Scanning Electron Microscopy (HR-SEM), and the elementary analysis was performed by Energy-Dispersive X-ray Spectroscopy (EDS). Effective diffusivity of calcium (DefCa) and moisture (Defw) were calculated during pretreatment and drying, respectively and texture parameters were determined by double compression using a texturometer. The transport mechanism determined during calcium pretreatment was diffusion with a DefCa = 3.10 × 10-10 m2/s. Also, branched calcium microstructures in the cell walls of tissue were observed due to the calcium effect, it was supported by elemental analysis, which showed an increase of calcium in section restructured compared to non-restructured. During drying, Defw = 1.86 × 10-9 m2/s was higher in pretreated compared to non-pretreated samples with Defw = 1.17 × 10-9 m2/s, indicating a higher drying rate and moisture loss. The texture values changed significantly (α ≤ 0.05) due to calcium pretreatment and drying; the calcium microstructures caused higher cohesiveness, springiness, gumminess, and chewiness. Calcium modifies the microstructure and composition of papaya tissue; therefore, drying kinetics and texture parameters depend on this modification.

Evaluation of the Antimicrobial Efficacy of Herbal Extracts Added to Root Canal Sealers of Different Bases: An In Vitro Study

Aim

This study aimed to evaluate and compare the antimicrobial efficacy of root canal sealers of different bases when mixed with herbal extracts.

Materials and methods

An evaluation of three sealers (Endomethasone, AH plus, Apexit plus) mixed with three herbal extracts [Emblica officinalis (Amla), Myristica fragrans (Nutmeg) and Salvadora persica (Miswak)] was done against nine strains of bacteria at various time intervals using the agar diffusion test. Moreover, measurement of the mean zones of inhibition was done.

Results

The largest zones of bacterial growth inhibition were observed with Endomethasone mixed with Myristica fragrans (Nutmeg) followed in the descending order by AH plus mixed with Salvadora persica (Miswak) and Apexit plus mixed with Salvadora persica (Miswak) respectively. The differences between zones of inhibition among different groups were found to be statistically significant.

Conclusion

Zinc-oxide-eugenol-based sealer (Endomethasone) mixed with herbal extracts produced the largest inhibitory zones followed in the descending order by resin-based sealer (AH plus) and calcium-hydroxide-based sealer (Apexit plus), respectively.

Clinical significance

Herbal plants such as [Emblica officinalis (Amla), Myristica fragrans (Nutmeg) and Salvadora persica (Miswak)] are rich sources of bioactive compounds that possess antimicrobial properties. Mixing their extracts with endodontic sealers can produce additive antimicrobial effect against microbes found in inflamed pulp.

How to cite this article

Devi MT, Saha S, Tripathi AM, et al. Evaluation of the Antimicrobial Efficacy of Herbal Extracts Added to Root Canal Sealers of Different Bases: An In Vitro Study. Int J Clin Pediatr Dent 2019;12(5):398–404.

Diffusion of calcium hydroxide through dentinal tubules of retreated root canals: An in vitro study

Objective:

Studies about the dispersion of hydroxyl ions through dentin of endodontically retreated teeth are scarce. The present study aims at examining the diffusion of calcium hydroxide in vitro by recording the pH changes of retreated root canal using two types of calcium hydroxide preparations.

Materials and Methods:

A total of 45 recently extracted single-rooted mandibular first premolars were collected and cleaned from calculus and remains of periodontal tissue. The teeth so collected were stored in thymol 10% solution till use. During collection, teeth with cracks, open apices, and restorations were excluded. Root canal preparations were performed using Protaper rotary system files, till #F3 file. All canals were obturated using cold lateral condensation and zinc oxide-based sealer. After 7 days, all gutta-percha were removed and the canals were irrigated with normal saline. The teeth were then randomly distributed into three groups. Canals in Group I were kept empty without any dressing to serve as a negative control group, Canals in Group II were filled with a freshly prepared mixture of calcium hydroxide powder with normal saline solution, and Group III was filled with Metapex. Periodically, the calcium hydroxide material was removed and the pH was measured using pH meter at 7, 10, 14, and 30 days.

Results:

The pH values of Group II and III ranged between 9.2 and 11.2. This was found to be highly significant against the negative control group. After 7 and 10 days, freshly mixed Ca(OH)₂ showed the higher pH than the creamy Metapex, and statistically the difference was highly significant after 10 days (P<0.001). After 14 days, Metapex group pH was higher than freshly mixed Ca(OH)₂, but it was not statistically significant as they reached nearly the same pH after 30 days (P>0.05).

Conclusion:

All Ca(OH)₂ preparations had high pH around the roots after 7 and 10 days. Metapex continued to have higher pH after 14 days.