scholarly journals Evaluation of the clinical success of four different types of lithium disilicate ceramic restorations: a retrospective study

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Sharo Abdulrahman ◽  
Constantin Von See Mahm ◽  
Ranjdar Talabani ◽  
Darwn Abdulateef
Keyword(s):  
Failure Rate ◽  
Survival Probability ◽  
Lithium Disilicate ◽  
Time Dependent ◽  
Time To Failure ◽  
Ceramic Fracture ◽  
Cumulative Survival ◽  
Kaplan Meier ◽  
Different Types ◽  
Ceramic Restorations

Abstract Background/purpose How long do lithium disilicate restorations last before they fail? The aim of this study was to assess the success rate of four different types of restorations made from lithium disilicate. Materials and methods A total of 87,203 ceramic restorations, classified into four different types (inlay or onlay, veneers (Vs), single crowns (SCs), and fixed partial dentures (FPDs)), were used. All were made of lithium disilicate (IPS e.Max CAD) with Cerec Inlab CAD/CAM system (Sirona Dental Systems, Bensheim, Germany). They were reported by dentists and entered in the database of the private B&R Dental Center between March 2015 and June 2020 and assessed retrospectively up to a period of 5 years based on the following parameters: failure rate and cause of failures (ceramic fracture, debonding, marginal adaptation, color match, endodontic intervention, periodontal disease, and secondary caries). Failure distribution according to gender, arch, and teeth type was also evaluated. The time-dependent time-to-failure/complication and their differences were calculated in months according to the Kaplan Meier and log-rank tests. The Chi-squared test (p 0.05) was used to assess the variations in causes of failure rates between different restorations. Results Kaplan Meier test showed overall cumulative survival probability of lithium disilicate restorations for up to years was 85.08%. Inlay/onlay and Vs ceramic restorations showed highest cumulative survival probability (99.4%, 98.6, respectively). FPDs had the least cumulative survival probability (52.9%) which was significantly (P < 0.00001) higher than for other ceramic restorations using the log-rank test. Moreover, overall time-dependent time-to-failure/complication occurred after 52.373 months according to Kaplan–Meier (CI: lower bound: 51.875 months; upper bound: 52.871 months). Ceramic fracture in both FPDs and SCs (27.6% and 26.6%, respectively) and debonding in Vs (12.7%) were significant as the main reasons for failure (P = 0.000). The failure rate was significantly higher for the maxillary arch than the mandibular arch (P = 0.021). Fracture and marginal discrepancy were more frequent in the molar region (77.5% and 14.75%, respectively) and significantly higher here than in the anterior and premolar regions (P = 0.000). Conclusion The medium-term performance of lithium disilicate is ideal. Ceramic fracture was the most common cause of failure in SCs and FPDs. FPDs presented with the highest failure rate based on evaluation for up to 5 years.

scholarly journals Esthetic Rehabilitation of Anterior Dentition with Different Types of Ceramic Restorations: Two Case Reports

2021 ◽  
Author(s):  
Michal Krump ◽  
Zelmira Krumpova
Keyword(s):  
Case Reports ◽  
Lithium Disilicate ◽  
Dental Prostheses ◽  
All Ceramic ◽  
Different Types ◽  
Fixed Dental Prostheses ◽  
Selection For ◽  
Ceramic Restorations ◽  
Single Crowns ◽  
The Ideal

AbstractAll-ceramic systems represent an excellent restorative alternative for fixed dental prostheses, single crowns, and veneers in the anterior dentition. With respect to improved mechanical properties, lithium disilicate ceramic material provide a broad range of indications, and extended veneers can serve as an alternative to full crowns. Although ceramic veneers represent a more conservative approach compared to crowns, the correct indication is essential to achieving the ideal outcome. The following case reports describe two types of fixed restorations of the anterior dentition: extended lithium disilicate ceramic veneers and lithium disilicate full crowns. Factors influencing treatment selection for each type of restorations are presented.

Real Time Reliability Study of a Model with Increasing Failure Rates

2011 ◽  
Vol 110-116 ◽  
pp. 2774-2779
Author(s):  
Mani Sharifi ◽  
Ehsan Hashemi ◽  
Peyman Farahpour
Keyword(s):  
Failure Rate ◽  
Reliability Function ◽  
Spare Parts ◽  
Time Dependent ◽  
Main Element ◽  
Time To Failure ◽  
Reliability Study ◽  
The Third ◽  
Working Element ◽  
Mean Time

This paper deals with a system with elements with one element is the main element and the other elements are the spare parts of the main element. If one element fails, one of the spare parts starts working immediately. The failure rate of non working elements are zero and the failure rate of working element is time dependent as and the failed elements are not repairable. The system works until all elements failed. In the second part of this paper the differential equations between the state of the system are established and by solving this equation the reliability function of the system () is calculated. In the third part, a numerical example solved to determine the parameters of the system. Nomenclature The notations used in this paper are as follows: : Number of elements, : Failure rate of each element at time, : Probability that the system is in state with spare element at time, : Probability that system works at time, : Mean time to failure of the system,

Ceramic fracture in metal-ceramic restorations: the aetiology

Dental Update ◽  
2017 ◽  
Vol 44 (5) ◽  
pp. 448-456
Author(s):  
Ayesha Aslam ◽  
Danish Azeem Khan ◽  
Syed Hammad Hassan ◽  
Bilal Ahmed
Keyword(s):  
Ceramic Fracture ◽  
Metal Ceramic ◽  
Ceramic Restorations

scholarly journals High Expression of Cathepsin D in Non-Hodgkin’s Lymphomas Negatively Impacts on Clinical Outcome

2010 ◽  
Vol 28 (3) ◽  
pp. 167-183 ◽  
Author(s):  
Giuseppina Nicotra ◽  
Federica Manfroi ◽  
Carlo Follo ◽  
Roberta Castino ◽  
Nicola Fusco ◽  
...  
Keyword(s):  
Clinical Outcome ◽  
Tumor Cells ◽  
Survival Probability ◽  
Cathepsin D ◽  
Rank Test ◽  
Lysosomal Protease ◽  
T Cell Lymphomas ◽  
Kaplan Meier ◽  
Punctate Pattern ◽  
Hodgkin's Lymphomas

The lysosomal protease Cathepsin D (CD) has been implicated in the homeostasis of lymphatic tissues. We investigated whether the level of CD expression influences the progression and the clinical outcome in Non-Hodgkin’s Lymphomas (NHLs). The expression of CD was assessed by immunohistochemistry and immunofluorescence in biopsies of Diffuse Large B Cell Lymphomas (DLBCL, 35 cases), Follicular Lymphomas (FL, 9 cases of grade I-II plus 14 cases of grade IIIB), Chronic Lymphocytic Leukaemias (CLL, 17 cases) and Peripheral T-cell Lymphomas (PTCL, 5 cases). CD staining showed a cytoplasmic punctate pattern compatible with its lysosomal localization. Based on the level of CD expression and the proportion of positive cells, lymphomas were classified as ‘low expressing’ (< 20% of tumor cells) or ‘highly expressing’ (≥ 20% of tumor cells). Lymphomas highly expressing CD were associated with a worse stage (III-IV) at diagnosis (31/34 cases;p= 0.002) and with a poor clinical outcome (i.e., partial remission and death; 28/34 cases;p= 0.03). In the subgroup of aggressive/high grade of malignancy lymphomas (i.e., DLBCL, FL IIIB and PTCL), the Kaplan-Meier curve revealed a very low cumulative overall survival probability (~20% at 5 year) for patients bearing a NHL with > 40% CD-positive cells compared to that of patients bearing a NHL with < 20% CD-positive cells (~70% at 5 year). This correlation was statistically significant (log-rank test,p= 0.01). In Cox multivariate analysis CD failed to be a prognosticator independent of pathologic stage, though the hazard ratio confirmed the association of low expression with a better survival probability. These data indicate that the presence of a high percentage of CD-positive tumor cells negatively reflects on the progression of NHLs.

scholarly journals Effect of Grid Instability on Power Generation System's Reliability

2020 ◽  
pp. 27-37
Author(s):  
Joseph Benedict Bassey ◽  
Isaac F. Odesola
Keyword(s):  
Power Generation ◽  
Power Plant ◽  
Failure Rate ◽  
System Reliability ◽  
Power Distribution ◽  
Power Plants ◽  
Time To Failure ◽  
Generation System ◽  
Reliability Indices ◽  
Mean Time

Aims: Reliability assessment of power generation system may be performed with the concept of system adequacy, security or both. Grid being a major component in the power distribution chain is seen to have some influence on the state of the generation system reliability because of the perturbation that may arise from it. In this study, the generation system reliability is evaluated using both the system adequacy and security concept. Study Design: To capture the system security problems attributed to grid disturbance, the generation system is structured into two component systems (1 - generation component and 2 - transmission component) with a series arrangement. Methodology: The reliability indices such as, mean time to failure, mean time to repair, failure rate and repair rate are assessed on component bases and with respect to the entire generation system. Results: The effect of failure rate of the transmission component on the entire generation system failure rate was evaluated as 66.25%, 55.55%, 33.33%, 55.00% and 35.72% in year 2013, 2014, 2017 2018 and 2019 respectively for FIPL Power Plant and 52.94%, 82.35%, 61.38% and 100% effect was evaluated in the year 2016, 2017, 2018 and 2019 respectively for GT5 of Omoku Power Plant. Conclusion: These results showed that there is a significant influence of grid disturbances on the reliability state of the two gas turbine power plants in Nigeria. Measures on possible reliability state improvement of the power generation systems were suggested to include training and retraining of technical personnel on the management of major equipment in the generation and transmission stations. 

scholarly journals Evaluation of Bond Failure Rate of Orthodontic Brackets Bonded with Green Gloo-Two Way Color Changes Adhesive: A Clinical Study

1970 ◽  
Vol 29 (2) ◽  
Author(s):  
Zuber Ahamed Naqvi ◽  
Saleem Shaikh ◽  
Zameer Pasha
Keyword(s):  
Failure Rate ◽  
Sampling Technique ◽  
Orthodontic Brackets ◽  
Rank Test ◽  
Dental Arch ◽  
Failure Rates ◽  
Bond Failure ◽  
Color Changes ◽  
Kaplan Meier ◽  
Significant Difference

BACKGROUND: Bonding is an important step in fixed orthodontic mechanotherapy. Many new materials introduced an adhesive for bonding. This study was designed to evaluate the clinical bond failure rate of orthodontic brackets bonded with green glue: two way color changes adhesive and transbond XT adhesive paste.METHODS: Eighteen male patients with a mean age of 16 years were included in the study. Convenience sampling technique was used to select the sample for this study. The split-mouth design was used to bond 360 brackets by one operator and both adhesives were used in each patient. Bond failure rates were estimated with respect to bonding procedure, dental arch, tooth type (incisor, canine, and premolar). The results were evaluated using the chisquare test. Kaplan – Meier analysis and the log rank test were used to estimate the survival rate of the brackets. Bracket failure rates for each system were analyzed, and failure causes as reported by the patients and the quadrant of each tooth in which bracketsfailed were recorded.RESULTS: The bond failure rate was 5.00% and 4.44% for green gloo and transbond XT group. No significant difference was found in the bond failure rate between transbond XT and Green gloo group. No significant difference was found in the bond failure rate between the two groups, in relation to right and left side and the type of teeth.CONCLUSION: Green gloo adhesive can be effectively used to bond orthodontic brackets.

Abstract 14293: Time to Wound Healing and Major Adverse Limb Events in Patients With Critical Limb Ischemia Treated With Endovascular Therapy

Circulation ◽  
2015 ◽  
Vol 132 (suppl_3) ◽  
Author(s):  
Grant W Reed ◽  
Negar Salehi ◽  
Pejman Raeisi-Giglou ◽  
Umair Malik ◽  
Rami Kafa ◽  
...  
Keyword(s):  
Wound Healing ◽  
Endovascular Therapy ◽  
Critical Limb Ischemia ◽  
Proportional Hazards ◽  
Limb Ischemia ◽  
Major Amputation ◽  
Cox Proportional Hazards ◽  
Time Dependent ◽  
Kaplan Meier

Introduction: There have been few studies evaluating the influence of time to wound healing on outcomes in patients with critical limb ischemia (CLI) after endovascular therapy. Methods: In this prospective study, patients with CLI treated with endovascular therapy were assessed for comorbidities, presence of wounds, wound healing, and major adverse limb events (MALE; major amputation, surgical endartectomy, or bypass) over time. The incidence of MALE was compared across patient and wound characteristics by Kaplan-Meier analysis. Associations between these variables and MALE were determined by Cox proportional hazards analysis. Results: A total of 252 consecutive patients with CLI were treated between November 1, 2011 and April 1, 2015; 179 (71%) had wounds, of which 97 (54%) healed. During median follow-up of 12.7 months (interquartile range 3.9 - 23.9 months), 46 (18%) had MALE. Wounds were associated with a greater risk of MALE (Hazard Ratio [HR] 3.5; 95% Confidence Interval [CI] 1.4-8.9; p=0.008). As a time-dependent covariate, wound healing was associated with less MALE (HR 0.23; 95% CI 0.10-0.53; p<0.001), and MALE was more frequent in patients with unhealed wounds (23% vs 11%; p<0.0001) (Figure - A). There was significantly less MALE in patients whose wounds healed within 4 months (24% vs 10%; p=0.032) (Figure - B), and less major amputation in those with healed wounds within 3 months (16% vs 5%; p=0.033). After multivariate adjustment for age, presence of diabetes, renal function, wound size, and procedural failure, independent predictors of MALE were wound healing as a time-dependent covariate (HR 0.18; 95% CI 0.08 - 0.40; p<0.0001), and creatinine ≥ 2 (HR 2.3; 95% CI 1.3-4.2; p=0.005). Conclusions: A shorter time to wound healing is associated with less MALE in patients with CLI after endovascular therapy. Efforts should be made to achieve wound healing as quickly as possible in this population, especially in those with renal dysfunction.

Tolerance, survival and adherence to treatment with methotrexate in patients with rheumatoid arthritis

2019 ◽  
pp. 13-17
Author(s):  
J.M. Sevillano Gutierrez ◽  
D. Capelusnik ◽  
E.E. Schneeberger ◽  
G. Citera
Keyword(s):  
Rheumatoid Arthritis ◽  
Adverse Events ◽  
Descriptive Statistics ◽  
P Value ◽  
Multiple Logistic Regression ◽  
Adherence To Treatment ◽  
Exact Test ◽  
Cumulative Survival ◽  
Kaplan Meier ◽  
Chi2 Test

Background: Methotrexate (MTX) is the most frequently used medication in patients with Rheumatoid Arthritis (RA). However, several authors have questioned its success due to the presence of adverse events and the lack of adherence. Objectives: to determine cumulative survival of MTX, frequency and type of adverse events and causes of discontinuation in patients with RA. Methods: consecutive patients 18 years and older with a diagnosis of RA (ACR/EULAR 2010 criteria), who had begun treatment with MTX during their disease were included. Sociodemographic, clinical and therapeutic data were collected. Date of initiation and suspension of MTX, route of administration, concomitant treatments, consumption of coffee and tobacco, presence of adverse events (AE) were all consigned. Adherence was evaluated using the Compliance Questionnaire Rheumatology questionnaire 5-item summary version (CQR5). Statistical analysis: descriptive statistics. Chi2 test or Fisher’s exact test; Survival of treatment by Kaplan-Meier and log Rank. Multiple logistic regression. A p value <0.05 was considered significant.

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