Comparative Evaluation of Fragment Reattachment and Fracture Resistance of Tooth Stored in Different Hydration Media when Reattached with Different Materials: An In-vitro Study

Introduction: Different methods have been developed to restore an uncomplicated crown fracture, varying from less invasive procedures to aesthetic restorations. Fragment reattachment has been established as a better alternative for restoring aesthetics, anatomy, and improved function. The rationale of the study lies in the fact that the materials used in the study are readily available and has proved beneficial in many literatures. Aim: To compare the tooth reattachment success and fracture resistance between tooth remnant and reattached part using different reattachment materials when the fragments were in different storage conditions. Materials and Methods: The present in-vitro, experimental study was conducted at Guru Nanak Institute of Dental and Research, Panihati, West Bengal, India, Indian Institute of Engineering Science and Technology, Shibpur and Narula Institute of Technology, Agarpara for one and half years, July 2022 to December 2023. A total of 96 Maxillary permanent central incisors extracted due to periodontal problems with approximately similar dimensions, mesiodistal width at the junction of middle and incisal third approximately between 8.4 to 8.7 mm were included in the study. Sample was divided into four groups: 1 positive control (A) and 3 experimental, based on storage media (B- Normal Saline, C- Fat-free milk, D- Stored Dry). Each experimental group was further subdivided into three sub-groups according to the different reattachment material (1- Light cure GIC; 2- Nano-filled packable Composite; 3- Flowable Composite). Tooth fracture was simulated and then the fracture fragments were stored as per the standard rehydration protocol for each group and reattached accordingly. The samples were then mounted on a Universal Testing Machine (UTM) to evaluate fracture resistance. The tooth reattachment success was noted by calculating the distance between the reattached tooth fragment from the reattachment material using Scanning Electron Microscopy. One-way Analysis of Variance (ANOVA) and Tuckey’s post-hoc tests were used for intergroup and intragroup comparisons. The level of significance was fixed at p=0.05 and any value ≤0.05 was considered to be statistically significant. Results: It was seen that significant differences were seen in fracture resistance based on different storage media and different reattachment materials. Among the samples, it was found that the fracture resistance is the highest in packable composite in the fat-free milk media with a mean value of 278.09 (SD 9.54). Also, it was found that distance between restoration and tooth surface is the smallest in packable composite in the fat-free media with a mean value of 1.4131 µm (SD 0.12880). These differences were statistically significant. Conclusion: The success of reattachment of a fractured anterior tooth with its fractured fragment was affected greatly by the rehydration of the fragments and also by the type of reattachment material used.