Evaluation of Bacterial Growth on Different Dental Materials

Essentials of Dentistry (Essent Dent), cilt.5, sa.0056, ss.1-8, 2026 (TRDizin)

Background: This study aimed to evaluate the effects of rinsing and disinfecting dental materials,

including acrylic resin denture bases, shellac, ceramics, and metal alloys, that were contaminated

with saliva before being placed in a dental cast.

Methods: Three hundred fifty-two (N = 352) cylindrical samples of 4 mm in height and 10 mm in

diameter were prepared, 88 of each dental material (acrylic resin denture base, shellac, ceramic,

and metal alloy). The samples were divided into 4 groups, each containing 22 samples. All samples

were contaminated with 25 μL of unstimulated saliva and were treated differently: some

were rinsed in cold running tap water, others were scrubbed with soap and cold running tap

water, and still others were soaked in 2% glutaraldehyde. As controls, some samples were contaminated

with saliva and left untreated (n = 22). Sheep blood agar plates were inoculated and

incubated at 37°C for 72 hours. The colonies of bacteria were counted after 24 hours. Data were

analyzed using ANOVA (P < .05), and the Kruskal–Wallis test was used for specific comparisons.

Results: This study demonstrated that rinsing saliva-contaminated dental materials for 20

seconds under cold running tap water significantly reduced bacterial contamination (P < .05).

Similarly, scrubbing with antiseptic soap or immersion in 2% glutaraldehyde solution for 20 seconds

effectively reduced bacterial contamination.

Conclusion: The findings of this study demonstrated the importance of rinsing or disinfecting

dental materials after use in the patient’s mouth and before placement in a dental cast to prevent

cross-infection. These results can significantly contribute to increasing infection control

measures in dental clinics and laboratories.

Keywords: Bacterial growth, cross-infection, dental materials, disinfection, saliva contamination