Comparative CBCT Based Outcome of Single and Multi Visit Non Surgical Endodontic Therapy Performed in Teeth with Chronic Apical Abscess A Randomized Clinical Trial

Chronic apical abscess is an inflammatory response to pulpal infection and necrosis, typically charaterized by a gradual onset, minimal or absent discomfort and an intermittent dischargevof pus through an associated sinus tract, Radiographically, this abscess often present with signs of osseous destruction, such as a radiolucency.

According to Sathorn et al. in 2005, approximately 70% of endodontist treat these cases with single visit non surgical endodontic therapy. Single visit non surgical endodontic therapy gained popularity due to several advantaged including reduced flare up, convenience, improved patient acceptance and better practice management (Walton & Fouad, 1992; Imura & Zuolo 1995). However, teeth with chronic apical abscess and sinus tract exhibit a complex infectious pattern in the apical root canal sysytem and periapical lesion, often involving biofilms (Ricucci D, 2018). Mechanical debridement combined with antibacterial regimen using 0.5% sodium hypochlorite has been shown to render 40-60% of treated teeth bacteria negative (Bystrom & Sjogren et al. 1997).

A recent retrospective study by Artaza et al in 2021 reported a success rate of 79.3% for single visit treatment of cases with sinus tract, indicating that 2 out of 10 cases has failed. The present of sinus tract in a tooth with long standing infection can negatively influence the resolution of apical periodontitis, thereby increasing the likelihood of treatment failure. Moreover, in chronic cases, due to the deeper penetration of microbiota into the root canal, effective disinfection cannot be achieved in a single visit. Additionally, dressing the canal with calcium hydroxide for one week can increase the percentage of bacteria free teeth to approximately 70% (Law & Messer, 2004). Given that this regimen further reduces bacterial load, it can be hypothesized that multiple visit treatment, incorporating calcium hydroxide dressing between appointments, may yield higher healing rates compared to single visit treatment without calcium hydroxide dressing in teeth with chronic apical abscess.

Therefore, to solve the dilemma for management strategy for chronic apical abscess there is a compelling need for well designed clinical trials to evaluate whether it should be treated with single or multi (two) visit. The impact of single or multi (two) visit non surgical endodontic therapy using Cone Beam Computed Tomography (CBCT)  in cases of chronic apical abscess has not been studied previously in the literature. Hence, this study aims to conduct a Randomized Clinical Trial (RCT) following CONSORT guidelines, evaluating the CBCT based outcome of single and multi (two) non surgical endodontic therapy performed in teeth with chronic apical abscess.