Comparative evaluation of four delivery vehicles for optimized local drug delivery in periodontal therapy: An in vitro study

Background: Periodontal disease affects approximately 50% of adults globally, necessitating effective antimicrobial interventions. Local drug delivery systems offer targeted therapy with minimal systemic exposure, but optimal vehicle selection remains challenging. Materials and Methods: An in vitro dissolution study was conducted using chitosan gel, polylactic acid microspheres, collagen sponge, and ethyl cellulose strips as delivery vehicles. Each vehicle was loaded with either doxycycline hyclate (25%) or metronidazole (25%) and subjected to release studies in simulated gingival crevicular fluid at 37°C for 14 days. Drug release was quantified using ultraviolet-visible spectrophotometry at predetermined intervals. Results: Ethyl cellulose strips demonstrated the most sustained release profile for both antibiotics, with 82.4% ±3.2% doxycycline hyclate and 78.6% ±2.8% metronidazole released over 14 days. Chitosan gel showed rapid initial burst release (42.3% ±4.1% within 24 h) followed by sustained release. Polylactic acid microspheres exhibited biphasic release patterns with 68.5% ±3.6% cumulative release. Collagen sponges showed the fastest release (95.2% ±2.4% within 7 days). Significant differences were observed between vehicles ( P < 0.001). Conclusion: Ethyl cellulose strips provide optimal sustained antibiotic release for periodontal applications, maintaining therapeutic concentrations over 2 weeks. Vehicle selection significantly impacts drug release kinetics and therapeutic efficacy.