OBJECTIVE: This study aimed to assess the amount of moisture present in the TWS of dental units in dental teaching hospitals (DTH) and private clinics (PC) across Karachi. METHODOLOGY: A total of 285 dental units were included in the study out of which 250 belonged to DTH and 35 to PC. Gushing was initially performed on hand to remove visible moisture from the TWS. The number of gushes required to remove visible moisture were recorded and the moisture-sensing device was used to assess the amount of invisible moisture in dry-air released from the TWS. SPSS v 22 was used to compare data of DTH and PC with the help of Mann Whitney U test. The pre- and post-exposure humidity of the sensing chamber was analyzed through Wilcoxon signed rank test. p value of < 0.05 was considered as significant. RESULTS: The power of the study was found to be > 99%. The moisture was present in 77.6% of the TWS in DTH and 37.1% in PC (p <0.001). Significantly higher number of hand gushes were required in DTH to eliminate the visible moisture as compared to PC (p= 0.022). Similarly, TWS in DTH were seen to liberate significantly increased amount of invisible moisture as compared to PC (p-value<0.001). CONCLUSION: Alarmingly high number of three-way syringes of dental units in dental teaching hospitals had moisture. This moisture can jeopardize restorative treatment and may expose patient to lethal microbes. KEYWORDS: Three way syringe; Restorative; Moisture; Resin Composite; Contamination