Efforts to enhance the mechanical and physicochemical properties of conventional glass ionomer cement (GIC) are ongoing. This study aimed to evaluate the effect of incorporating varying concentrations of frankincense and myrrh liquids into conventional GIC on its microhardness and sealing ability. Frankincense and myrrh liquids were prepared by dissolving 25 g of each ground resin in 50 mL of distilled water at 60 °C and allowing the solutions to stand for 8 h. Five experimental groups were evaluated: Group A (conventional GIC), Group B (15% frankincense-modified GIC), Group C (25% frankincense-modified GIC), Group D (15% myrrh-modified GIC), and Group E (25% myrrh-modified GIC). Microhardness was evaluated using a Vickers hardness tester, and sealing ability was evaluated via interfacial gap measurements using scanning electron microscopy (SEM). SEM analysis revealed that all modified GIC groups exhibited significantly smaller interfacial gap sizes (Groups B–E: 6.1, 5.22, 5.9, and 5.34 µm, respectively) compared to conventional GIC (Group A: 6.88 µm). However, there were no statistically significant differences in microhardness among the groups (p > 0.5). The incorporation of 15% and 25% concentrations of frankincense or myrrh liquids into conventional GIC significantly improved sealing ability without compromising hardness.

Essential oils are a common alternative to chloroform for dissolving gutta–percha. This study evaluated the antimicrobial effects of chloroform and six essential oil gutta–percha solvents: eucalyptus oil, orange oil, clove oil, rosemary oil, grapefruit oil, and castor oil, against Enterococcus faecalis and Candida albicans by using disk diffusion techniques. The impregnated sterile disk with 10 μL of pure, tested solvents was inoculated on agar plates at three time contacts: 3 min, 10 min, and 24 h. The mean diameter of the zone of inhibition (ZOI) of each solvent was measured after 24 h of incubation. Against Enterococcus faecalis, in both 3 min and 10 min contact, rosemary oil had the largest ZOI (11.40 ± 0.90 and 11.55 ± 0.68 mm), and orange oil showed the smallest ZOI (7.90 ± 0.31 and 9.05 ± 0.68 mm), respectively. Eucalyptus oil exhibited ZOI with persistence, while grapefruit oil and castor oil showed no ZOI. After 24 h of contact, the largest ZOI was recorded for orange oil. Against Candida albicans, at all three time points, clove oil produced the largest ZOI (20.25 ± 0.82, 23.10 ± 0.93, 30.59 ± 0.74 mm) and chloroform the smallest (10.4 ± 0.77, 9.85 ± 0.62, 11.6 ± 0.65 mm), for 3 min, 10 min, and 24 h, respectively. Conclusively, clove oil, orange oil, and rosemary oil exhibit significant antimicrobial activity like chloroform.