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The aim of this study was to evaluate the increase in temperature induced by various light sources during in-office bleaching treatment, under simulated blood microcirculation in pulp conditions. Ten freshly extracted human maxillary central incisors were used for the study. The roots of the teeth were removed from approximately 2 mm below the cementoenamel junction and fixed on an apparatus for the simulation of blood microcirculation in pulp. A J-type thermocouple wire was inserted into the pulp chamber through an artificial access at the lingual surfaces of the teeth, and another thermocouple wire was fixed on the labial surface of the teeth meanwhile. An in-office bleaching agent, intense red in color and with 30% water content, was applied to the labial surfaces of the teeth, and repeating measurements were made for each tooth using three different light sources: Er:YAG laser (40 mJ, 10 Hz, 20 s), 810-nm diode laser (4 W, 20 s, CW), and high-intensity light-emitting diodes (LED) (1,100 mW/cm(2), 20 s) as the control. Temperature increase in the pulp chamber and within the bleaching gel during light application were recorded and statistically evaluated. The highest pulp temperature increases were recorded for the diode laser group (2.61 °C), followed by the Er:YAG laser (1.86 °C) and LED (1.02 °C) groups (p < 0.05; analysis of variance (ANOVA), Tukey's honestly significant difference (HSD)). Contradictorily, the lowest gel temperature increases were recorded for diode laser (6.21 °C) and followed by LED (12.38 °C) and Er:YAG (20.11 °C) groups (p < 0.05; ANOVA, Tukey's HSD). Despite the significant differences among the groups, the temperature increases recorded for all groups were below the critical value of 5.6 °C that can cause irreversible harmful changes in pulp tissue. It can be concluded that, with regard to temperature increase, all the light sources evaluated in this study can be used safely for in-office bleaching treatment within the described parameters.

For all tested attachments on both models, the stress was concentrated on the ipsilateral implant. The bar-clip system allowed the distribution of load to all supporting implants in both models. Although the highest stress level observed with all attachment systems was moderate, the bar-Easy Slot attachment showed the highest stresses. The lowest stress was observed with the single anchor attachment (ERA) design for both models. Varying the number of implants had no significant effect on stress values around supporting implants.

A positive influence on oral health-related QoL was observed in all groups. The QoL values were the most improved in the implant-retained overdenture group.

This article describes the fabrication of implant-supported overdentures and removable partial dentures attached to anterior fixed partial dentures utilizing impression techniques to transfer the position of implants and record soft tissue areas in a functional state.

It can be difficult to achieve superior esthetics in implant-supported fixed partial dentures (FPDs). Zirconia ceramics with high flexural strength and esthetic can be treatment options for implant-supported FPDs. This article describes a simple and reliable method to fabricate a retrievable cemented implant-supported zirconia FPD.

Objective This study aimed to evaluate the effect of artificial accelerated aging (AAA) on color stability, surface roughness, and microhardness of three laminate veneer (LV) materials. Materials and Methods Specimens of ceramic LV (CLV‐IPS E.max Press), hand‐layered composite LV (hand‐layered laminate veneer [HLV]‐Tetric N‐Ceram), and prefabricated composite LV (prefabricated laminate veneer [PLV]‐Componeer Coltene) were prepared as discs (n = 10). CIE L*, a*, and b* color coordinates, the Vickers microhardness, and surface roughness were measured 24 hours after preparation and reevaluated after aging for 300 hours in an ultraviolet (UV)‐AAA system (Ci35 Weather‐Ometer). Color difference (CIEDE2000 [ΔE00]) was calculated. Data were statistically analyzed with the Shapiro‐Wilk test and the Kruskall‐Wallis test followed by the Mann‐Whitney U tests (α = .05). Results All of the LV groups showed significant differences in ΔE00 after AAA (P < .001). Comparing the color changes of the HLVs with the PLVs, no significant difference could be found (P = .705). There was a statistically significant difference in the means of changes in microhardness among the LVs materials (P < .001). The changes in surface roughness results showed a significant difference after AAA in all the LVs (P < .001). Conclusions Within the limitations of this in vitro study, the color stability, the microhardness, and surface roughness of tested LVs were influenced by AAA. Clinical significance The prefabricated composite LV system does not replace the individualized ceramic LV technique, but rather offers an alternative to hand‐layered LVs, which is delicate and time‐consuming technique.