Single-visit versus multiple-visit non-surgical endodontic therapy

This doctorial thesis begins with a systematic review on clinical studies on single-visit and multiple-visit non-surgical endodontic treatment. The review found that neither single-visit treatment nor multiple-visit treatment could guarantee the absence of postoperative pain. Since the study design of many studies displays significant limitation, and the materials and equipment used in endodontic treatment have dramatically changed in recent years, prospective randomised clinical trials are needed to further verify the postoperative pain and success rate of single-visit versus multiple-visit endodontic treatment. This study also performed a systematic review on clinical studies on core-carrier obturation. A meta-analysis concluded that the success rate of endodontic treatment using core-carrier obturation is high (79%), and the incidence of postoperative pain is low (11%). Most teeth (87%) had adequate adaptation using core-carrier obturation material but one third of them had overfilling. A questionnaire survey was conducted to investigate the preference for single-visit and multiple-visit endodontic treatment among the 16 registered endodontists and 800 randomly selected general dentists in Hong Kong. Eight endodontists and 429 general dentists returned their questionnaires and the results found most endodontists (88%) and general dentists (93%) preferred offering multiple-visit treatments. The two commonest reasons for choosing multiple-visit treatment for both endodontists and general dentists were the positive effects of inter-appointment medications and that the tooth to be treated had doubtful prognosis. Three randomised clinical trials were performed in this study at two clinics, one in The University of Hong Kong (HKU) in Hong Kong and the other in Peking University (PKU) in Beijing. The first clinical trial compared the time in performing non-surgical endodontic therapy with or without the use of a magnifying loupe. Ninety-six teeth were treated with a magnifying loupe and 86 teeth were treated without a magnifying loupe. The results found the use of a magnifying loupe could significantly reduce the endodontic treatment time. The results also showed that treatment time was associated with preoperative pain, number of root canal, number of treatment visit, experience of operator and site of treatment (HKU or PKU); but not associated with age, gender, tooth vitality, or the presence of apical radiolucency or sinus tract. The second clinical trial compared the incidence of post-obturation pain at one and seven days after single-visit and multiple-visit non-surgical endodontic treatment. A total of 538 teeth from patients attending were evaluated. The result found single-visit or multiple-visit endodontic treatment had no difference in their incidence of postoperative pain, which was not uncommon after one day (29%) but was infrequent (5%) after seven days. The third clinical trial was performed at HKU clinic to compare the success rate, prevalence of postoperative pain and chairside time of single-visit and multiple-visit endodontic treatment. A total of 220 teeth were followed up for at least 18 months. The average follow-up period was 29 months. The results found that the success rate and prevalence of postoperative pain of single-visit or multiple-visit treatment had no significant difference. The chairside time for single-visit treatment was shorter than multiple-visit treatment.published_or_final_versionDentistryDoctoralDoctor of Philosoph