OBJECTIVES: The aim of this in vitro study was to evaluate the effects of the thickness and shade of 3 types of computer-aided design/computer-aided manufacturing (CAD/CAM) materials. MATERIALS AND METHODS: A total of 120 specimens of 2 shades (A1 and A3) and 2 thicknesses (1 and 2 mm) were fabricated using VITA Mark II (VM; VITA Zahnfabrik), IPS e.max CAD (IE; IvoclarVivadent), and VITA Suprinity (VS; VITA Zahnfabrik) (n = 10 per subgroup). The amount of light transmission through the ceramic specimens was measured by a radiometer (Optilux, Kerr). Light-cured resin cement samples (Choice 2, Bisco) were fabricated in a Teflon mold and activated through the various ceramics with different shades and thicknesses using an LED unit (Bluephase, IvoclarVivadent). In the control group, the resin cement sample was directly light-cured without any ceramic. Vickers microhardness indentations were made on the resin surfaces (KoopaPazhoohesh) after 24 hours of dark storage in a 37°C incubator. Data were analyzed using analysis of variance followed by the Tukey post hoc test (α = 0.05). RESULTS: Ceramic thickness and shade had significant effects on light transmission and the microhardness of all specimens (p < 0.05). The mean values of light transmittance and microhardness of the resin cement in the VM group were significantly higher than those observed in the IE and VS groups. The lowest microhardness was observed in the VS group, due to the lowest level of light transmission (p < 0.05). CONCLUSION: Greater thickness and darker shades of the 3 types of CAD/CAM ceramics significantly decreased the microhardness of the underlying resin cement.
Ceramics* ; Curing Lights, Dental ; Fungi ; Hardness ; In Vitro Techniques ; Incubators ; Polytetrafluoroethylene ; Resin Cements*

BACKGROUND: Bloating is a common gastrointestinal complaint which is difficult to treat. OBJECTIVE: This study investigated the efficacy and compliance of a formulation called KAASER comprised of Trachyspermum ammi (L.) Sprague seed, Zingiber officinale Roscoe. rhizome and Piper nigrum L. berry in the treatment of functional bloating. DESIGN, SETTING, PARTICIPANTS AND INTERVENTION: A total of 106 patients with functional bloating, between 20 and 50 years of age, participated in this double-blind randomized controlled trial. Patients were divided into 3 parallel groups that received 500 mg of placebo, dimethicone or KAASER, three times a day for 2 weeks. MAIN OUTCOME MEASURES: The frequency and severity of bloating were primary outcomes, while the frequencies of eructation, defecation, borborygmus and early satiation were secondary outcomes. All parameters were evaluated at the beginning (week 0), and also weeks 2, 4 and 10 of the study, through self-report checklists with a scoring system. RESULTS: Among the 84 patients who completed the study, the frequency and severity of bloating (P < 0.001), the frequencies of eructation, defecation and borborygmus (P = 0.03) were significantly improved in the group receiving KAASER (36 patients) compared with the dimethicone (35 patients) and placebo (35 patients) groups, during the 3 phases of follow-up. These significant differences persisted through the 2 and 8 weeks of follow-ups after cessation of medication (week 4 and 10). In early satiation, no significant differences were observed among the 3 groups. CONCLUSION: The results showed that KAASER can be effectively used to treat patients suffering from bloating. Bloating, eructation, defecation and borborygmus in the KAASER group remained significantly improved after 2 and 8 weeks of cessation of medication, making this mechanism an interesting area for further investigation. TRIAL REGISTRATION Registration trial IRCT2015100324327N on Iranian Registry of Clinical Trials.