The Effect of Modified Framework Design on the Fracture Resistance of IPS e.max Press Crown after Thermocycling and Cyclic Loading.

AIM: This study aimed to investigate the effect of modified framework (MF) design on the fracture resistance of IPS e.max Press anterior single crown after thermocycling and cyclic loading. MATERIALS AND METHODS: Two types of IPS e.max Press frameworks were designed (n = 10); standard framework (SF) with a 0.5 mm uniform thickness and MF with a lingual margin of 1 mm in thickness and 2 mm in height connected to a proximal strut of 4 mm height and a 0.3 mm wide facial collar. The crowns were cemented to resin dies, subjected to 5,000 cycles of thermocycling, and loaded 10,000 cycles at 100 N. A universal testing machine was used to load specimens to fracture, and the modes of failure were determined. RESULTS: The mean and standard deviation (SD) of fracture resistance were 219.24 ± 110.00 N and 216.54 ±120.02 N in the SF and MF groups. Thus, there was no significant difference (p = 0.96). Mixed fracture was the most common failure mode in both groups. We found no statistically significant difference between the groups (p = 0.58). CONCLUSION: The MF design did not increase the fracture resistance of IPS e.max Press crown. CLINICAL SIGNIFICANCE: Framework design is an essential factor for the success of all-ceramic restorations and its modification might be regarded as an approach to increase fracture resistance. Furthermore, the modified design was evaluated in metal-ceramic or zirconia crowns while less attention was paid to the IPS e.max Press crowns. How to cite this article: Golrezaei M, Mahgoli HA, Yaghoobi N, et al. The Effect of Modified Framework Design on the Fracture Resistance of IPS e.max Press Crown after Thermocycling and Cyclic Loading. J Contemp Dent Pract 2024;25(1):79-84.

Functional and aesthetical full-mouth rehabilitation of a patient with severely worn dentition and deep bite using minimally invasive approach in current vertical dimension: A 3-year follow-up.

Key Clinical Message: Regaining restorative space for fullmouth reconstruction in a patient with deep bite and worn dentition by conservative approach in current vertical dimension and also using minimally invasive concept is recommended. Abstract: Full mouth reconstruction of a deep bite patient with severely worn dentition is a challenging situation for the prosthodontists. This study represents minimally invasive procedures in mentioned condition without increasing vertical dimension. After 3 years of follow up no complication was observed.

Comparison of the marginal and internal fit of PMMA interim crowns printed with different layer thicknesses in 3D-printing technique.

OBJECTIVE: The aim of this in vitro study was to compare the effect of printing layer thickness on the marginal and internal fit of interim crowns. MATERIAL AND METHODS: A maxillary first molar model was prepared for ceramic restoration. Thirty-six crowns were printed with three different layer thicknesses using a digital light processing-based three-dimensional printer (25, 50, and 100 µm [LT 25, LT 50, and LT 100]). The marginal and internal gaps of the crowns were measured with replica technique. An analysis of variance was conducted to determine if there were significant differences between the groups (ɑ = .05). RESULTS: The marginal gap of LT 100 group was significantly higher than that LT 25 (p = .002) and LT 50 groups (p ≤ .001). The LT 25 group has significantly larger axial gaps than LT 50 group (p = .013); however, there were no statistically significant differences between other groups. The LT 50 group showed the smallest axio-occlusal gap. The mean occlusal gap differed significantly by printing layer thickness (p ≤ .001), with the largest gap occurring for LT 100. CONCLUSIONS: Provisional crowns printed with 50 µm layer thickness provided the best marginal and internal fit. CLINICAL SIGNIFICANCE: It is recommended that provisional crowns be printed with a 50 µm layer thickness to ensure optimal marginal and internal fit.

Effect of nystatin and licorice on yeasts isolated from the oral lesions of patients with cancer under chemotherapy (in vitro study).

Background: Oral candidiasis is one of the most common manifestations of patients with cancer under chemotherapy. Due to many side effects of chemical antifungal products and various advantages of herbal extracts like licorice, this study was performed to compare the antifungal effects of nystatin and licorice on yeasts isolated from oral mucosa of patients with cancer receiving chemotherapy. Materials and Methods: In this in vitro study, a total number of 30 patients with oral candidiasis who received chemotherapy were examined. The samples were prepared by using swabs taken from the lesions, and after 48 h, they were transferred and cultured on Sabouraud dextrose agar. The antifungal effect of licorice was compared with nystatin using agar disk diffusion method. These data were entered in SPSS statistical software and were analyzed with Kruskal-Wallis and Mann-Whitney tests. (α = 5%). Results: Four types of candida were identified among all 30 oral lesions (Candida albicans, Candida glabrata, Candida stellatoidea, and Candida SP). The mean inhibition zone diameter around nystatin showed a significant difference (P < 0.001) between C. albicans (9.486), C. glabrata (8.627), C. stellatoidea (7.00), and C. sp (7.06) but the inhibition zone diameter around licorice was almost zero in all groups. Conclusion: Licorice extracts did not show any antifungal effects whereas nystatin showed the most antifungal effect against C. albicans.

Treatment Planning Challenges in Cases with Root Proximity: An Interdisciplinary Approach.

Root proximity is defined as a situation where the distance between the roots of adjacent teeth on radiographs is ≤1.0 mm. This important situation should be detected by clinicians before definitive restorative treatments and they should be well aware of different approaches available for the management of this situation. The purpose of this study was to collect and review the available literature on this topic by searching the PubMed, Google Scholar, Scopus, Embase, and Cochrane Library in order to summarize the complications and treatment plans for root proximity in cases requiring restorative procedures.

Rehabilitation of a deep bite patient with worn dentition using minimally invasive approach: A 3-year follow-up.

Full mouth rehabilitation of severely worn teeth represents a challenging situation for dental clinicians. This case report describes the minimally invasive interdisciplinary approach for treatment of severely worn dentition with a loss of vertical dimension of occlusion. After 3 years of follow-up, no complication was observed.

Oral reconstruction with hybrid implant-supported fixed prostheses in cases of mandibular defect using two methods along with 3 years of follow-up: A case report.

Ameloblastoma is an invasive odontogenic tumor, and for reconstruction, iliac graft and dental implants play an important role. This article evaluates the application of hybrid prostheses, clinical steps, and complications related to this treatment.