Evaluation of the micro effects of different calcium silicate containing agents in the treatment of partial amputation

Vital pulp treatments are defined as treatments aimed at preserving pulp tissue affected by caries, trauma or iatrogenic causes. The aim of these treatments is to stimulate the formation of reparative dentin to ensure continued development, especially in young permanent teeth where apical root development is incomplete. These treatment methods are simpler than root canal treatment, which is complex and difficult to perform, and are both cost and time efficient for the patient and dentist. Partial amputation (Cvek amputation) is defined as "removal of the affected portion of the coronal pulp to preserve the remaining coronal and radicular pulp." In partial amputation treatment, perforation size is one of the most important factors for successful treatment. As the perforation size increases, bacterial leakage increases. In this treatment method, the success rate is higher in teeth with a perforation size between 2 mm and 4 mm. There are other factors affecting the success of partial amputation treatment. Firstly, the infected superficial pulp tissue must be meticulously removed until a healthy pulp surface is achieved. Secondly, the pulp base material to be used should be both biocompatible and impermeable to prevent bacterial contamination of the remaining pulp tissue. Although the sealing ability of bonding systems and composite resins has been greatly improved over the last decade, there is still no clear evidence on the durability and the effectiveness of bonding systems in preventing bacterial microleakage around the restoration. To address potential marginal leakage of the restoration, it is crucial to ensure that the base materials used for pulp protection provide an enhanced seal. In addition, they must not conduct heat, show no shrinkage or expansion, be easily placed in the cavity, be radiopaque, ensure continued pulp viability, have a short clinical application time, induce reparative dentin formation, and have a high bond strength to the dentin and restorative materials. Calcium silicate cements have excellent sealing properties, especially compared to Ca(OH)², in preventing the entry of microorganisms into the pulp chamber. However, the curing time for these materials, which can vary from 15 minutes to 4 hours, poses a challenge for their practical application in pediatric patients. Theracal PT is a newly introduced calcium silicate-containing agent, and it is promoted for its ability to reduce clinical time due to its dual-cure curing method. However, there are limited studies examining the success of this material. In this thesis, occlusal cavities were generated in 90 extracted impacted wisdom teeth. The extent of microleakage following partial amputation using the conventional base material ProRoot MTA and Theracal PT was assessed. This assessment included perforations of 2 mm and 4 mm in width, and the evaluation was conducted under in-vitro conditions utilizing a high-resolution micro computed tomography system. According to the results of the study, TheraCal PT group was statistically significantly more successful than ProRoot MTA group in teeth with partial amputation at 2 mm perforation size. In teeth with 4 mm perforation size partial amputation, although there was no statistically significant difference between the two abutment agents, the microleakage was lower in the TheraCal PT group. The microleakage value increased as the perforation size increased regardless of the base agent used. Theracal PT, a newly introduced product for partial amputation treatment, particularly in young permanent teeth, has demonstrated comparable success to conventional calcium silicate-containing agents in addressing microleakage. This research, serving as a precursor to future in-vivo studies, offers support for the integration of this base material into standard clinical practice. Keywords: Micro-CT, Microleakage, Partial amputation, ProRoot MTA, Theracal PT