ABSTRACT
OBJECTIVE: The aim of this study was to evaluate the marginal adaptation and fracture resistance of feldspathic and Polymer-Infiltrated Ceramic Network (PICN) CAD/CAM endocrowns for maxillary premolars. MATERIALS AND METHODS: Twenty extracted human permanent maxillary premolars were randomly divided into two groups (n = 10); Group CEREC (GC), which was produced by feldspathic ceramic and the Group Enamic (GE), which was produced by PICN. All teeth were endodontically treated and decoronated horizontally at 2 mm above the cemento-enamel junction. Endocrown preparations were done with 4 mm depth into the pulp chamber. Endocrowns were manufactured using CAD/CAM from ceramic blocks. Following adhesive cementation, all specimens were subjected to thermocycling. Marginal adaptation evaluated under SEM at 200 × magnification. Each specimen was fixed in a universal testing machine and a compressive load was applied at 45° to long axis of the teeth until failure. Failure load was recorded and failure modes were evaluated. Statistical analyses were performed with SPSS 19.0 software and data were compared using Mann-Whitney U test. RESULTS: There were no significant differences in the marginal adaptation between two groups (P > 0.05). GE presented significantly higher fracture resistance when compared to GC (P < 0.05). Failure pattern was similar and characterized by the tooth-ceramic fracture on the force-applied side. CONCLUSIONS: CAD/CAM fabricated feldspathic ceramic and PICN endocrowns provide sufficient marginal adaptation, but the PICN endocrowns shows higher fracture resistance than the feldspathic ceramic endocrowns.
Subject(s)
Bicuspid/physiopathology , Ceramics/chemistry , Crowns , Dental Porcelain/chemistry , Dental Prosthesis Design/methods , Polymers , Tooth Fractures/physiopathology , Computer-Aided Design , Dental Cavity Preparation/methods , Dental Porcelain/therapeutic use , Dental Prosthesis Design/adverse effects , Dental Restoration Failure , Dental Stress Analysis , Humans , Materials Testing , Resin Cements , Stress, Mechanical , Tooth Cervix/injuriesABSTRACT
BACKGROUND AND OBJECTIVE: The aim of this study was to compare the levels of levels of interleukin-37 (IL-37) in gingival crevicular fluid, saliva and plasma in patients with periodontal disease and patients with healthy periodontium and to correlate these levels with clinical parameters. MATERIAL AND METHODS: Samples of gingival crevicular fluid, whole saliva and plasma were collected from systemically healthy, nonsmoker periodontally healthy controls (group 1, n = 20), gingivitis patients (group 2, n = 20) and chronic periodontitis patients (group 3, n = 20). Full-mouth clinical periodontal parameters, including probing depth, plaque index, gingival index and bleeding on probing, were also recorded. IL-37 levels in the biofluid samples were determined by ELISA. Data were tested statistically using the Kruskal-Wallis test followed by the Mann-Whitney U-test. RESULTS: The concentration of IL-37 in gingival crevicular fluid was significantly lower in group 3 than in groups 1 and 2 (p = 0.001), whereas the total amounts in gingival crevicular fluid samples were similar (p > 0.05). The salivary and plasma concentrations of IL-37 were similar in the study groups (p > 0.05). There were negative correlations between gingival crevicular fluid IL-37 concentrations and gingival crevicular fluid volume in all groups (p < 0.05). There was also a negative correlation between the gingival crevicular fluid IL-37 concentration and gingival index in group 3 (p < 0.05). CONCLUSIONS: IL-37 was expressed in all biofluids. According to our findings, the total amount of IL-37 in gingival crevicular fluid, or salivary or plasma concentrations of IL-37, may not be useful diagnostic markers to differentiate periodontal disease and the periodontally healthy condition. The difference in gingival crevicular fluid IL-37 concentration between the study groups may be a result of the variation in gingival crevicular fluid volume, as suggested by the negative correlation between gingival crevicular fluid volume and gingival crevicular fluid IL-37 concentration. In the light of our findings, it seems that IL-37 is not involved in periodontal disease. Further comprehensive studies may clarify this issue more clearly.
