Introduction: In the work scope of the dentist, the cross infections risk between patients, dentists, and laboratory officer could appear through saliva, plaque, and blood during the printing process. The prevention of the risk in the moulding process could be prevented through immersion and spray disinfection techniques. The extract of aloe vera in 25% concentration could be utilized as a disinfection solution in the alginate mould. The objective of this research was to obtain the technical impact of immersion and spray alginate mould dimensions. Methods: This research used the method of laboratory experiments with pretest-posttest control group only by involved 27 samples which each divided into 3 groups. The first group with immersion by aloe vera in 25% concentration, the second group with the spray by Aloe vera 25% concentration, and control group. The data were analyzed using a nonparametric test: Kruskal Wallis dan Man Whitney. Results: Based on the result of Wilcoxon toward all treatments are generated that the technical immersion of Aloe vera 25% concentration could afford to influence the alginate mould dimension as vertically and horizontally with result P=0.008 (P< 0.05). Based on the result of the Kruskal Wallis test, identified there was a significant difference between the three groups. Where the ranking order starts from the smallest onto the biggest in sequence for the control group, spray Aloe vera 25% and immersion of Aloe vera 25%. Based on the test of Mann-Whitney is obtained result P<0.05 that there was a significant difference. Conclusion: From this research could be stated there is the technical impact of immersion techniques using Aloe vera in 25% concentration towards the stability of alginate mould dimension.