Purpose: This study evaluated the effect of a high-power solid-state light emitting diode (LED) curing unit on the dentin bond strength of a composite resin with self-etching primer adhesives by means of microtensile bond test.
Materials and Methods: The flat dentin surfaces of the extracted human molars were prepared. Each surface was treated with either two self-etching adhesive systems (Clearfil SE Bond, Clearfil Tri-S Bond) and a photocure composite was placed. The adhesive and composite were photocured with a high-power LED, a conventional LED, or a halogen light curing unit. In high-power LED group, the exposure time was reduced 3 or 5 s for the adhesive and 5 or 10 s for the composite. The specimens were trimmed to obtain the stick shape specimens and the micro-tensile bond strengths were measured. The spectrum of the wavelength of each light curing unit was also measured.
Results: In Clearfil SE Bond group, the microtensile bond strengths of high-power LED light curing unit groups were statistically lower than that of a halogen light curing unit group. In Clearfil Tri-S Bond group, there were no statistical differences in the microtensile bond strengths between halogen and high-power LED light curing unit groups, when the composite was photocured for 10 s. The spectrum of both high-power and conventional LED light curing units had a single sharp peak around 465 nm. The conventional halogen light curing unit showed broad spectra.
Conclusion: A high-power LED curing unit affected the dentin bond strength of a composite resin with self-etching primer adhesives.

Purpose: Denture adhesives are used to improve denture retention, stability and function. The purpose of this study was to determine the effect of a cream-type denture adhesive on bite force until denture dislodgement (BFDD) using an improved gnathometer.
Materials and Methods: Twelve denture-wearing patients (six females and six males, mean age: 69 years) were involved in the study. The maximum BFDD of two groups (“no biting pain” and “biting pain”) was measured using a disposable gnathometer before and after denture adhesive application. The standard curve of the gnathometer measurements was produced using a constant load compression testing machine from 10 N to 80 N.
Results: A significant difference was found between the no biting pain group and the biting pain group before the application of denture adhesive (p<0.0001). A notable improvement was observed in BFDD of the biting pain patients after denture adhesive was applied (p<0.0001). No significant difference in BFDD was found in the no biting pain subjects following the application of denture adhesive.
Conclusion: The following conclusions were drawn: 1) Denture adhesive is effective for improving the BFDD of complete denture wearers with biting pain; 2) The gnathometer is useful for measuring the BFDD of complete denture wearers.

This article reports bonding technique and clinical performance of ceramic fixed partial dentures (FPDs) applied to a metal allergic patient. Frameworks of mandibular four- and three-unit FPDs were fabricated with a tetragonal zirconia polycrystal (TZP) material (Cercon) and veneered with feldspathic porcelain (Cerabien ZR). After try-in, the surface to be bonded was air-abraded with alumina (0.2 MPa), and treated with a single liquid primer (Alloy Primer) that contained a hydrophobic phosphate monomer (MDP). Abutment dentin surfaces were etched with 10% citric acid-3% ferric chloride (10-3) aqueous solution, and the FPDs were bonded with a tri-n-butylborane (TBB) initiated adhesive resin (Super-Bond C&B). After an observation period of two years, both FPDs were functioning satisfactorily. The materials and procedure reported here are applicable as an option for a prosthodontic treatment for the patients incompatible to specific metallic elements.