ABSTRACT
BACKGROUND: Flexural strength (FS) of denture base resins (DBRs) had been improved by reinforcing it with different glass fibers. However, a limited data are available on the effect of glass fiber reinforcement with conventional heat-cured resin after prolonged water storage. AIMS AND OBJECTIVES: This study aimed to evaluate the reinforcing effect of novel S-glass and nylon fibers on the FS of acrylic DBRs. It also aimed to evaluate the effect of glass fiber reinforcement on the FS of acrylic DBRs after a prolonged storage in water. MATERIALS AND METHODS: One hundred and sixty identical specimens were fabricated in specially designed molds according to the manufacturer's instructions. The three experimental groups were prepared consisting of conventional (unreinforced) acrylic resin, novel S-glass fiber-reinforced and nylon fiber-reinforced acrylic resin. The specimens were fabricated in a standardized fashion for each experimental group. Each group was further subdivided into two groups on the basis of storage conditions (dry and wet). FS was tested using a three-point universal testing machine at a crosshead speed of 5 mm/min. Glass fiber-reinforced group was further tested after prolonged storage in distilled water. Entered data were statistically analyzed with one-way ANOVA and least significant difference post hoc test. RESULTS: In this study, statistically significant differences were noted in the FS of all the groups. S-glass fiber-reinforced group had highest FS compared to the other two groups (P < 0.001). Nylon fiber-reinforced group had lowest FS. All the groups stored in distilled water revealed a decrease in strength compared to those stored in dry atmosphere. Among wet specimens, those stored for 3 weeks had a significantly higher FS than those stored at one and 2 weeks (P < 0.01). CONCLUSION: Within the limitations of this investigation, the FS of heat-cured acrylic DBR was improved after reinforcement with glass fibers. It can be recommended to strengthen distal extension partial and complete denture bases. Nylon fibers may not be desirable for strengthening acrylic denture bases.
ABSTRACT
CONTEXT: Both intraoral autogenous bone grafting (ABG) and platelet-rich fibrin (PRF) offer a useful treatment modality for periodontal regeneration of intrabony defects (IBDs). However, predictable regeneration in patients with severe attachment loss is a challenge to the practitioners. AIM: The aim of this study was to compare the clinical efficacy of PRF with ABG for the treatment of IBDs in chronic periodontitis. SETTINGS AND DESIGN: This is a randomized controlled trial. MATERIALS AND METHODS: Twenty chronic periodontitis patients with IBDs were randomly treated by PRF or ABG. Probing pocket depth (PPD), relative attachment level (RAL), surgical reentry bone fill, and radiographic bone fill (RBF) were recorded at baseline, 3, 6, and 9 months postsurgery, respectively. STATISTICAL ANALYSIS: Student's t-test was used for continuous variables. All means were expressed as mean ± standard deviation and proportions were expressed in percentage. The level of significance was set at P < 0.05. RESULTS: Both PRF and ABG sites produced a significant improvement from baseline to 9 months for all the parameters. However, there was no significant difference between the two treatment modalities in the reduction of PPD and RAL gain at 9 months. In addition, ABG showed significantly greater RBF (30.34%) as compared to PRF (20.22%). Similar findings were supported by surgical reentry, where a surgical reentry of 65.31% at ABG sites and 43.64% at PRF sites was seen. CONCLUSION: Both ABG and PRF can be used predictably to reconstruct lost periodontal structures as indicated by PPD reduction and RAL gain. However, in terms of osseous defect fill, ABG yields more definitive outcome than PRF.
