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Comparative Evaluation of the Efficacy of Chlorhexidine, Sodium Hypochlorite, the Diode Laser and Saline in Reducing the Microbial Count in Primary Teeth Root Canals – An In Vivo Study

Vidhi Walia, Mousumi Goswami, Shivesh Mishra, Nidhi Walia, Divya Sahay




Introduction:One of the primary goals of pulpectomy is to decrease the sum total of microorganisms and disinfect the tooth root canal system. To achieve this, mechanical preparation, irrigation, disinfection and obturation of the root canal is necessary. The present study was set out to evaluate the difference in the antibacterial efficacy of primary teeth root canals either irrigated with Chlorhexidine,Saline,and Sodium hypochlorite or irradiated with a Soft tissue Diode Laser(980nm, Photon Plus, Zolar Tech &Mfg Co. Inc, Ontario, Canada).

Methods: 60 primary teeth of children requiring pulpectomy were divided into 4 groups of 15 each, Group 1 (2% Chlorhexidine), Group 2 (1 % Sodium hypochlorite), Group 3 (Laser irradiation) and Group 4 (Saline). Pulp tissue was extirpated from the canals and the samples were collected using sterile absorbent paper points. After cleaning and shaping, the root canals of the teeth in each group were irrigated usingsodium hypochlorite, chlorhexidine, and saline or were irradiated with the laser. The samples were obtained again and sent for microbiological examination.

Results – The Colony Forming Unit counts from pre-disinfection sample served as a baseline for comparisons throughout the study. The mean bacterial colony counts of all the isolated bacteria reduced after irrigation or irradiation. Intergroup comparisons showed no significant difference when Groups 1, 2, and 3 were compared to each other(p>0.05).However, a significant difference was seen when Groups 1, 2, 3 were compared to Group 4(p<0.05).

Conclusion: 2% Chlorhexidine, 1% Sodium hypochlorite and Laser irradiation succeeded in reducing the root canal infection. Hence, diode laser irradiation may be a possible supplement to existing protocols for disinfecting the root canal system.


Pulpectomy; Chlorhexidine; Sodium hypochlorite; Diode laser


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DOI: https://doi.org/10.22037/jlms.v10i4.19215