Evaluation of the Fracture Resistance of Different Designs of All-Resin Post and Core Systems: An In Vitro Study.

Introduction There is a growing demand for post and core systems that offer both ease of use and efficiency. Recently introduced dual-cure build-up and post cement materials exhibit properties similar to dentin. The objective of this laboratory experiment is to compare the fracture resistance among three distinct post and core systems and identify the locations of failures within each group. Material and methods This in vitro experimental study involved 30 epoxy resin-based blocks (Endo Training Bloc J, Dentsply Sirona, Ballaigues, Switzerland) divided into three groups: The first group was a post space preparation and restoration with a fiber post (RelyX™ Fiber Post, 3M ESPE, Saint Paul, Minnesota, United States) 1.6 mm in diameter and 10 mm in length (Group A) where core build-up and cementation were performed using a dual-cure build-up and cement for endodontic post resin material (Core X Flow, Dentsply DeTrey, Konstanz, Germany). The second group was a post space preparation and restoration using a dual-cure build-up and cement for endodontic post resin material, 10 mm in length filled with resin but without fiber post placement (Group B). The third group was where post space and core were filled and restored with a dual-cure build-up and cement for endodontic post resin material, 5 mm in length and without fiber post placement (Group C). Subsequently, samples were mounted and tested using a universal testing machine (Instron, Canton, Massachusetts, United States), and the fracture site was located. Results Significant differences were identified among the three groups, indicating the impact of both post length and type on fracture resistance (p-value <0.05). Group B exhibited the highest mean compressive strength resistance and maximum load at 899.3330 (N), followed by Group C at 848.9690 (N) and Group A at 751.9620 (N). The predominant failures in the samples were core fractures or debonding of the core material. Conclusion All-resin posts demonstrated high fracture resistance, unlike fiber posts which displayed inferior fracture resistance.

Awareness about emergency management of avulsed tooth among intern dentists-a cross-sectional observational study.

Tooth avulsion is a frequently encountered dental emergency. Children are commonly reported group due to frequent sports activities, trauma, accidents and falls. Prompt emergency management is vital for long term success and to avoid morbidity. The study was aimed to assess the understanding of intern dentists about the emergency handling of avulsed teeth cases as mostly they are first responders among health care personnel. In this study a fourteen-item questionnaire with predefined responses was shared as online Google survey form with intern dentists of 5 different dental teaching hospitals of Islamabad, Pakistan. The duration of the study was 6 months (01 March 2022 to 31 August 2022). The questions were intended to collect personal information and to check level of knowledge and awareness about the management of avulsed tooth among the dental interns. The data was analyzed by statistical methods and is presented through tables and descriptive methods. In total, 152 participants completed the shared questionnaire. The vast majority (71%) of them were aware of the initial management of avulsed teeth, 49% were aware of the ideal transport medium for an avulsed tooth, (43%) were aware of the critical time for successful replantation, while (62%) had knowledge of the multiple factors responsible for the outcome of the tooth replantation. For majority of the statements, female participants had better knowledge as compared to their male counterparts. Statistically significant difference was noted for the statement "If you found the knocked-out tooth and it is dirty what will be your initial approach?" with female participants having better knowledge as compared to the male (p value = 0.005). Based on our study results, generally dental interns are well-informed but still lack expected level of awareness regarding the proper management protocol for avulsed tooth. Hence, improvement is needed regarding the effective handling of avulsed teeth cases.

Effectiveness of Chitosan versus Natural Aloe Vera on Candida Adherence in Denture Soft Lining Material.

Background: Soft denture lining materials act as a cushion between the denture base and tissues. Alongside having many advantages, its main problem is candida growth due to its rubbery and porous texture. Many interventions have been performed to halt the growth of candida within soft lining materials such as the use of antifungal therapy and strict oral and denture hygiene but there are consequences such as recurrence, drug resistance, and toxicity related to these interventions. Since natural agents such as aloe vera and chitosan have been proven to have antibacterial and antifungal properties with minimum adverse effects, this study aimed to study the effectiveness of chitosan and aloe vera powders incorporated within denture soft lining materials against candida adherence. Methodology. A total of 60 soft-lining material samples were prepared that were equally divided into three groups, viz., group 1 (chitosan incorporation), group 2 (aloe vera incorporation), and group 3 (control). Candida was obtained from the microbiology lab to form a candidal suspension, diluted in 0.9% NaCl to match the McFarland standard bacteriologic solution. Samples were incubated at 37°C for 24 hours in test tubes containing 100 mL of the candidal suspension and 9.9 mL of the previously prepared Sabouraud dextrose agar. Crystal violet stain was used to stain the adhering cells by fixing them with methanol 80%. For each sample, the adhering candida cells were counted on three standard fields by using an inverted light microscope, and the mean of those fields was recorded. Results: The mean value for samples containing aloe vera was 41.15, while the mean values for samples containing chitosan and the control group were 16.05 and 79.1, respectively. Of all the three groups, aloe vera powder had a significant efficacy against candida growth as compared to the chitosan and control groups (P value = 0.001). Conclusion: Both herbal agents were effective against candida growth. In comparison, aloe vera was more effective against candida growth compared to chitosan.

Effects of using Antifungal Gel on Retentive Bond Strength of Two Forms of Denture Adhesives: An in vitro Study.

AIM: The purpose of this in vitro study is to compare the bond strength to denture acrylics efficacy of miconazole gel against two denture adhesives with improved retentive properties (zinc-free PoliGrip cream and Snug denture soft cushion). MATERIALS AND METHODS: Eight heat-cured acrylic samples were prepared measuring 0.7 cm × 1.4 cm flat tested surface. The two well-adapted tested surfaces were matched and fixed to Universal Testing Machine clamp. Vertical separating load was applied at a rate of 1 mm/min to yield the maximum load before denture adhesive failure occurs. These measurements were used to express the retention bond strength when improved denture adhesive material was applied alone in comparison with micon-azole nitrate gel. Results were analyzed using one-way analysis of variance (ANOVA) statistical analysis at p-value of < 0.05. RESULTS: There was a statistically significant reduction in the mean tensile strength when the antifungal gel was opposed by the zinc-free PoliGrip cream. However, such a significant difference was not evident when the Snug denture cushion was opposed by the miconazole gel. CONCLUSION: The addition of antifungal gel to denture adhesives reduces retentive bond strength of denture adhesives to denture acrylics. However, if an antifungal gel has to be used, then a denture adhesive cushion soft plastic liner may provide a better retentive option than denture adhesive cream. CLINICAL SIGNIFICANCE: The incorporation of an antifungal agent into denture adhesives is required in many denture patients to suppress fugal growth and eliminate the undesirable health effects associated with such infections.