Disinfection of 3D-printed surgical guides using virgin coconut oil (in vitro study)

Abstract

Background/objective: Disinfection of a 3D-printed surgical guide is of utmost importance as it comes into contact with hard and soft tissue during implant placement so it poses a potential risk of pathogenic transmission. Methods used for disinfection in the surgical field should be reliable, practical, and safe for the instruments and the patients. The objectives of this study were to compare the antimicrobial potential of 100% Virgin Coconut Oil, 2% Glutaraldehyde, and 70% Ethyl Alcohol used to decontaminate 3D-printed surgical guides.

Materials and methods: Thirty identical surgical guides were printed and cut into two halves (N = 60). Both halves were then contaminated with a defined amount of human saliva samples (2 ml). The first half (n = 30) was sub-grouped into three study groups which were immersed in one of the three disinfectants for 20 min as follows; group VCO was immersed in 100% Virgin Coconut Oil, group GA was immersed in 2% Glutaraldehyde, and group EA was immersed in 70% Ethyl Alcohol. The second half (n* = 30) was sub-grouped into three control groups which were immersed in sterile distilled water as follows group VCO*, group GA*, and group EA*. The microbial count was expressed as colony-forming units per plate and the comparison of the antimicrobial potential of the three tested disinfectants between the three study and three control groups was done using the One-Way ANOVA test.

Results: The culture results of three study groups revealed no bacterial growth with the highest % of reduction in the mean microbial count of the oral microorganisms (about100%) and an uncountable bacterial growth was shown between the three control groups (more than 100 CFU/plate) representing the baseline of the oral microorganisms. Therefore; statistically significant differences were found between the three control and three study groups (P < .001).

Conclusion: The antimicrobial potential of Virgin Coconut Oil was comparable and equivalent to Glutaraldehyde and Ethyl Alcohol with a significant inhibitory action against oral pathogens.

Keywords: 3D-printing; Disinfection; Surgical guides; Virgin coconut oil.

Fig. 1

Flow chart of the study design

Fig. 2

Tooth supported surgical guide designed with bilateral missing second premolars and first molars placed on a study cast

Fig. 3

a Ten identical surgical guides were printed using a clear photoreactive resin material b 3D-printed surgical guides were removed from the build platform using a removing tool

Fig. 4

15 ml Falcon tube filled with sterile distilled water and placed on the Scilogex Vortex Mixer

Fig. 5

The mean bacterial count of the two halves of the surgical guides between the three control and three study groups

Fig. 6

Culture results from the control group on Blood (A) and MacConkey (B) agar plate

Fig. 7

Culture results from the study group disinfected with 2% GA on Blood (A) and MacConkey (B) agar plate

Fig. 8

Culture results from the control (A) and the study group disinfected with 70% EA (B) on Sabouraud agar plate

Fig. 9

The mean bacterial count after taking a direct sample from the first half of the surgical guides disinfected with 100% VCO

Fig. 10

Culture results of the direct sample taken from the study group disinfected with 100% VCO on Blood (A) and MacConkey (B) agar plate

Fig. 11

Culture results from the control (A) and the study group disinfected with 100% VCO (B) on Sabouraud agar plate