## 4 Discussion
Additionally, a pathway for bacterial invasion and recurrence of infection of the root canal system may also be created by the residual filling becoming loose, twisted, or vibrated during post space preparation [30; 31]. It may be difficult to maintain the required post length for retention and a sufficient amount of gutta-percha for an adequate apical seal. According to research by [PERSON] et al., an apical seal is directly proportional to the length of the remaining obtated material in the root canal. It is important to maintain 4-5 mm of the remaining obturing material in the apical area to provide a safe margin [32]. However, it might not be possible to maintain the 4-5 mm of apical remaining gutta-percha in all post and core treated teeth. According to [PERSON] et al. [10], it may be essential to extend post preparations such that at-least 3 mm of the remaining gutta-percha is left in the root canal in cases where the root length is short. It is clinically accepted to extend the post space preparations such that 3 mm to 5 mm of gutta-percha remains at the apex of the tooth to maintain the apical seal. The dentinal walls of the post space prepared in the root canal must be clean for cement to adhere effectively [33]. To facilitate the cementation of the post with an adhesive resin cement and create hybrid zones between the resin cement and the dentinal tubules, the post space preparation should have a dentinal wall [34; 35]. Remnants of root canal filling material should not be left inside the root canal, as they cannot provide reliable cementation or bonding to the dentinal walls [36; 37]. The amount of filling material left on the canal walls is reduced as the canal is enlarged beyond the initial preparation size [38]. An unsatisfactory clinical outcome was observed in 50% of the maxillary posterior teeth where there was a gap of more than 1 mm between the post and the gutta-percha. These findings are consistent with those of some research studies, which found that treating anterior teeth had a more favorable outcome than treating posterior teeth [39; 40]. Even though there are a number of different factors related to the clinical outcome of treatment, the anatomy of a multi-rooted tooth probably presents greater difficulties for the operator, especially for an undergraduate student. The post drill should have the same diameter as the prepared canal in order to reduce the amount of radicular dentine removal and retain the tooth's fracture resistance. Since the educational institutions inside the Kingdom of Saudi Arabia have separate male and female training sections, where male undergraduate students can treat only male patients and female undergraduate students can treat only female patients, it was also planned for the present study to identify the treatment outcome performed by male and female undergraduate students separately. The inclusion of gender differences may have indicated competence gaps between undergraduate students of both sexes and may have called for more training for the identified gender. In the past, extracted natural teeth have been used to teach post- and core-treatment techniques in preclinical simulation clinics. The current experiences with natural teeth constraints include ethical obstacles, cross-infection needs, finding teeth with the appropriate tooth structure, and procuring teeth with the proper root canal anatomy. Natural tooth variations make it difficult to standardize, replicate, and maintain consistency in instructions and teaching by the instructors. This can lead to a diverse range of learning experiences for students. The use of artificial typodont teeth in simulation teaching for post and core training in fixed prosthodontics has several advantages, including uniformity of teeth, uniformity of techniques, lifelike appearance, facilitation of repeatable practical demonstrations, and being readily available.