Post-Retained Single Crowns versus Fixed Dental Prostheses: A 7-Year Prospective Clinical Study

Biomechanical integrity of endodontically treated teeth (ETT) is often compromised. Degree of hard tissue loss and type of final prosthetic restoration should be carefully considered when making a treatment plan. The objective of this prospective clinical trial was to assess the influence of the type of prosthetic restoration as well as the degree of hard tissue loss on 7-y clinical performance of ETT restored with fiber posts. Two groups (n = 60) were defined depending on the type of prosthetic restoration needed: 1) single unit porcelain-fused-to-metal (PFM) crowns (SCs) and 2) 3- to 4-unit PFM fixed dental prostheses (FDPs), with 1 healthy and 1 endodontically treated and fiber post-restored abutment. Within each group, samples were divided into 2 subgroups (n = 30) according to the amount of residual coronal tissues after abutment buildup and final preparation: A) >50% of coronal residual structure or B) equal to or <50% of coronal residual structure. The clinical outcome was assessed based on clinical and intraoral radiographic examinations at the recalls after 6, 12, 24, 36, 48, and 84 mo. Data were analyzed by Kaplan-Meier log-rank test and Cox regression analysis (P < 0.05). The overall 7-y survival rate of ETT restored with fiber post and either SCs or FDPs was 69.2%. The highest 84-mo survival rate was recorded in group 1A (90%), whereas teeth in group 2B exhibited the lowest performance (56.7% survival rate). The log-rank test detected statistically significant differences in survival rates among the groups (P = 0.048). Cox regression analysis revealed that the amount of residual coronal structure (P = 0.041; hazard ratio [HR], 2.026; 95% confidence interval [CI] for HR, 1.031–3.982) and the interaction between the type of prosthetic restoration and the amount of residual coronal structure (P = 0.024; HR, 1.372; 95% CI for HR, 1.042–1.806) were statistically significant factors for survival (ClinicalTrials.gov NCT01532947)

Adherence to Mediterranean diet, physical activity level, and severity of periodontitis: Results from a university-based cross-sectional study

Background: The aim of this study was to evaluate the association between adherence to Mediterranean diet (MD) and physical activity (PA) level with the periodontal status of a University-based cohort of individuals. Methods: A total of 235 individuals were included in the study. MD adherence and PA level were registered through validated questionnaires, together with a full periodontal examination. Crude and adjusted odds ratios (ORs) [95% confidence interval] were calculated to evaluate the association between MD adherence, PA level, and periodontitis severity. A final logistic multivariate regression model was built to evaluate the impact of the combination between low MD adherence and low PA level on the prevalence of Stage III/IV periodontitis. Results: The adjusted ORs for Stage III/IV periodontitis were 1.65 [0.84 to 3.28; P&nbsp;=&nbsp;0.42] for low PA and 5.63 [3.21 to 9.84; P&nbsp;=&nbsp;0.00] for low MD adherence. The final logistic multivariate regression model resulted in OR&nbsp;=&nbsp;10.23 [4.01, 26.09; P&nbsp;=&nbsp;0.00] of having Stage III/IV periodontitis in individuals with low MD adherence and low PA. Conclusions: Individuals conducting a lifestyle characterized by the combination of low MD adherence and lack of regular exercise had 10 times the odds to have severe forms of periodontitis. © 2022 The Author

Functional implant prosthodontic score of a one-year prospective study on three different connections for single-implant restorations

Aim The aim of this prospective clinical trial was to analyze, using the Functional Implant Prosthodontic Score (FIPS), the clinical resultsof three different abutment-implant connections (1 hexagon vs 2 conical types) single-unit restorations after one year of clinical service. Material and methods Thirty patients were restored with cement-retained crowns on soft tissue level implants (10 TTc Windmix, 10 TTk Windmix and 10 Aadva GC) in posterior sites and followed-up for 1 year. FIPS was applied for objective outcome assessment beside clinical and radiographic examinations. Five variables were defined for evaluation, resulting in a maximum score of 10 per implant restoration. The patients’ level of satisfaction was recorded and correlated with FIPS. Results All implants and connected crowns revealed survival rates of 100% without any biological or technical complications after three years of loading. The total FIPS recorded for group 1 was 44, 43 in group 2 and 42 in group 3. The mean total FIPS score was 8.6±1.1, ranging from 6 to 10. The variable “bone” revealed the highest scores (2.0; range: 2–2), as well “occlusion” (2.0; range: 2–2). Mean scores for “design” (1.7 ±0.4; range: 1–2), “mucosa” (1.6±0.5; range: 1–2), and “interproximal” (1.5±0.6; range: 1–2) were more challenging to satisfy. The patients expressed a high level of functional satisfaction (80.5±2.5; range: 65–100). No type of connection showed to be superior to the other two. No statistically significant differences were found among the three tested groups. A significant correlation was found between FIPS and the subjective patients’ perception with a coefficient of 0.80 (P < 0.0001). Conclusions The findings of the clinical trial indicated the great potential of both conical and hexagon connections and their good performance after 1 year of clinical service. FIPS showed to be an objective and reliable instrument to assess implant success

A new generation of orthodontic retainer using 3D printing technology: report of two cases

Aim In this article the fabrication and use of new type 3D printed splint of retainer after orthodontic treatments is reported. Case report Two cases, one of an adoescent female patient and the other of an adult female, are presented, describing step-by-step the clinical and laboratory procedures. The controls after 6 months are also reported. Conclusion Further randomized clinical trials are required in order to evaluate durability and efficacy and periodontal parameters in patients treated with this new type of retainer

Etching a Fiber Post Surface with High-concentration Bleaching Agents

Introduction: Commonly, resin composites/cements fail to achieve proper bonding to fiber posts when their surfaces have not been previously etched. This study evaluated the effect of the concentration and application mode of hydrogen peroxide on the surface topography and bond strength of resin composite to glass-fiber posts. Methods and Materials: Fiber posts were immersed in 24% or 35% solutions (a high-concentration bleaching agent) of hydrogen peroxide (H2O2), or these solutions were applied over the post surface using a microbrush (n=10). Posts without any treatment were used as a control. After etching, the posts were silanated and an adhesive was applied. The posts were positioned in a mold, and a resin composite was incrementally inserted and light-cured. The post/resin assembly was serially sectioned into several beams that were subjected to a tensile bond strength test. The data were subjected to the two-way analysis of variance and Tukey test (α=0.05). The Dunnet's test was used to compare the experimental conditions to the control. The surface topography was analyzed using scanning electronic microscopy. Results: The non-etched post presented a relatively smooth surface without fiber exposure. Except for the application of 24% H2O2, the other experimental conditions increased the number of exposed fibers and bond strength in relation to the control. Although immersion resulted in higher values for the 24% H2O2 application, the mode of application did not alter bond strength when 35% H2O2 was used. Conclusions: The effect of the mode of application of H2O2 depended on its level of concentration. A high-concentration bleaching agent improved the bond strength of the resin composite to the post surface, regardless of which mode was used

Bond strength to radicular dentin of two experimental luting cements

Aim The aim of this study was to test two different of experimental cements based on two types of polymerization techniques comparing them with one already well known in the market. Materials and methods Thirty intact central incisors, extracted for periodontal reasons, were selected and endodontically treated, then were randomly divided into 3 groups of 10 samples: Group 1, light cured composite experimental material with self-etch adhesive and dual polymerization activator; Group 2, dual experimental core build-up with self-etch adhesive and dual-polymer activator; Group 3 (control group), dual cement with self-etch adhesive and dual polymerization activator. One fiber post was luted into the root canal strictly following manufacturer’s instructions. Each sample was cut in slices in order to perform the push-out bond strength test with a testing machine. To express the bond strength in MegaPascals (MPa), the breaking load recorded in Newton (N) was divided by the area of the bonded interface (A) in mm2. The area of the bond interface was calculated as the area of the surface of a truncated cone using the formula: A = π (R + r) [h2 + (Rr) 2] 1/2, where R represents the major radius of the coronal post, r represents the minor radius of the apical post and h is the thickness of the slice in millimeters. The diameters and thickness of the slice were measured individually using a digital caliper with 0.01 mm precision. After the test, each slide was observed to detect the type of failure and classified as adhesive between cement and dentin (AD); adhesive between the cement and the post (AP); fracture of the sample, cohesive inside the post and dentin (FR); cohesive in cement (CC); mixed (M). Results Group 2 recorded the highest values of adhesion strength, group 1 the lowest. There were no statistically significant differences among groups 1 and 2 and controls. The most common failure mode was the mixed one and the less frequent was the adhesive type between the post and the cement. Conclusions Within the limitations of this study, it can be concluded that the bond strength of experimental resin cements is comparable to that of a cement marketed by the same manufacturer, used here as a control and well known in the market

Adattamento interno e nanoinfiltrazione di corone singole in disilicato di litio con preparazione a finire e differenti cementi da fissaggio.

Scopo Lo studio si è proposto di analizzare in vitro la nanoinfiltrazione e l’adattamento interno di corone singole in zirconia. Materiali e Metodi Incisivi mandibolari sani sono stati preparati protesicamente per corone singole in zirconia e suddivisi in maniera randomizzata in 4 gruppi sperimentali in base al cemento utilizzato. I campioni sono stati processati per analisi della nanoinfiltrazione marginale e, successivamente, osservati per l’adattamento interno con stereomicroscopio e microscopio elettronico a scansione. Risultati Il valore medio di adattamento interno delle corone in zirconia è stato di 54,06 μ; nessuna corona ha presentato fratture marginali. Conclusioni L’utilizzo delle preparazioni a finire con corone singole in zirconia può essere consigliato nella pratica clinica