ABSTRACT
AIM: The objective of research was to evaluate the shear bond strength of two commercially available intraoral porcelain repair systems, Clearfil repair system (Kuraray) and P and R repair system (Shofu) for repairing cohesive and adhesive fracture in metal-ceramic restorations. SETTINGS AND DESIGN: In vivo - comparative study. MATERIALS AND METHODS: Ninety samples of Nickel-Chromium metal discs were fabricated. Each disc was veneered with 2 mm thickness of ceramic material using custom made metal jig. Samples were divided into control (Group I n = 10) and two test groups (Group II n = 40 and Group III n = 40). Adhesive and cohesive fractures were created in test group samples, Group II (Ceramic substrate or cohesive defect) and Group III (metal substrate or adhesive defect). The samples of ceramic substrate (Group II) and metal substrate (Group III) were further subdivided into A and B containing 20 samples each according to the repair material used (A; Clearfil porcelain repair system and B; P and R porcelain repair system). All specimens were subjected to a standard shear load in the UTM until fracture occurred. Data were analyzed using one-way analysis of variance and post hoc Bonferroni test. STATISTICAL ANALYSIS USED: One-way analysis of variance (ANOVA) and post hoc Bonferroni test. RESULTS: Clearfil repair system showed significantly higher shear bond strength value (29.16 Mpa) as compared to P and R repair system (27.23 Mpa) for cohesive fractures. Whereas if compared for repairing adhesive fractures P and R repair system had significantly higher shear bond strength values (26.59 Mpa) than Clearfil repair system (25.74 Mpa). CONCLUSIONS: From the present study, it was be concluded that for cohesive fracture Clearfil repair system is a better material and for adhesive fractures P and R repair material gives better results.
ABSTRACT
The aim of this article is to present the clinical application of immediate implant placement with L-PRF and immediate prosthetic loading in anterior esthetic region. A 24-year-old healthy female patient reported with a chief complaint of poor esthetics in the upper front tooth region with retained deciduous teeth. On oral examination, there were retained deciduous teeth (52, 53, and 63) with congenitally missing permanent successors. The retained deciduous teeth were extracted, and immediate implant placement was done in the extraction sockets along with L-PRF membranes in one surgical session under local anesthesia. Immediate temporization was performed with composite crowns on immediately placed dental implants. After 3 months of the healing period, the final implant-level impressions were made and the temporary composite crowns were replaced with the final zirconia porcelain crowns. A 12-month follow-up was made, and satisfactory esthetic and functional results were obtained.
ABSTRACT
A study was undertaken to evaluate the effect of artificial aging through steam and thermal treatment as influencing the shear bond strength between three different commercially available zirconia core materials, namely, Upcera, Ziecon, and Cercon, layered with VITA VM9 veneering ceramic using Universal Testing Machine. The mode of failure between zirconia and ceramic was further analyzed as adhesive, cohesive, or mixed using stereomicroscope. X-ray diffraction and SEM (scanning electron microscope) analysis were done to estimate the phase transformation (m-phase fraction) and surface grain size of zirconia particles, respectively. The purpose of this study was to simulate the clinical environment by artificial aging through steam and thermal treatment so as the clinical function and nature of the bond between zirconia and veneering material as in a clinical trial of 15 years could be evaluated.
ABSTRACT
PURPOSE: The rehabilitation of the edentulous mandible is a challenge due to various limiting factors, of which the available vertical restorative space (AVRS) has been well understood in the literature. However, other anatomic variations such as arch form, arch size, and also the interforaminal distance (IFD) (due to the presence of mandibular nerve) are influential in the selection of size and position of implants, and thereby the prosthetic design. MATERIALS AND METHOD: In the present study, 30 edentulous patients from a group of 300 edentulous patients, representing all the three jaw relations (Class I, II, and III) were evaluated for designing a classification that could help in a comprehensive treatment plan for the edentulous mandible. Dental panoramic radiographs of each individual with a trial or final prosthesis were made. The horizontal IFD and AVRS values were calculated. RESULTS: One-way analysis of variance followed by post-hoc test (multiple comparison) and Bonferroni method having P < 0.05 as significant value showed an overall mean of 38.9 mm for horizontal distance and 13.69 mm for the AVRS in 30 edentulous patients. CONCLUSION: The results showed that in the majority of cases (90%) there is insufficient space to place a bar attachment supported by five implants for mandibular overdentures. This suggests that a universal treatment plan cannot be followed due to varying anatomic factors. Hence, it becomes imperative to have a set of clinical guidelines based on the AVRS and IFD, for the selection of implant number and type of attachment. The article proposes a simple classification system based on the AVRS and IFD for establishing guidelines in the treatment planning of the edentulous mandible, to aid in selection of implant size, number, and position along with the associated prosthetic design.
