OBJECTIVE: Open Common Bile Duct Exploration (OCBDE) is a critical intervention for managing complex common bile duct (CBD) stones when endoscopic retrograde-cholangiopancreatography (ERCP) is unsuccessful. The choice of technique for choledochal exploration remains debated due to variable recurrence rates and complications associated with different methods. This study evaluates the clinical outcomes: bile leakage, oncogenic transformation, and stone recurrence of Choledochoduodenostomy (CDD) versus T-tube drainage (TTD), aiming to substantiate the selection of an optimal CBD closure strategy after choledocholithotomy. METHODS: We conducted a retrospective review of 138 patients who underwent OCBDE between January 1, 2016, and August 1, 2021, at our institution, following failed at least two ERCP interventions. Patients were stratified into two cohorts based on the surgical technique employed: CDD (Group-I) and TTD (Group-II). Clinical and surgical outcomes were meticulously compared between the groups. RESULTS: Group-I (CDD) included 109 patients (79%), while Group-II (TTD) comprised 29 patients (21%). Bile leaks were identified in 8 patients (5.8%), predominantly in Group-I (p=0.871). In the section of the study encompassing the 1.5-year period of the COVD-19 pandemic, the number of OCBDE surgeries performed remained consistent with the 3.5-year period preceding the pandemic. During the pandemic period, the number of operations increased, while the frequency of TTD surgery decreased (p<0.001). Two patients from Group-I developed bile duct malignancy during follow-up period (p=0.286). Higher incidence of stone recurrence was noted in Group-II (p=0.007). CONCLUSION: This investigation delineates the surgical outcomes of side-to-side diamond-shaped CDD compared to TTD, incorporating critical data from approximately 1.5 years of the COVID-19 pandemic. These findings are pivotal for guiding surgical strategy in complicated CBD stone management.