Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “restoration”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources
PubMed1976

Marginal leakage with different composite restorative materials: effect of restorative techniques.

The degrees of marginal leakage was tested for different restorative techniques with use of both ultraviolet-polymerized and cold-curing resins. All the materials tested showed severe marginal leakage when applied as conventional butt joint restorations. When the restorations were extended onto peripheral etched enamel, either with or without a sealant-primed etched surface, marginal leakage was prevented in most instances with both the cold-curing and ultraviolet-polymerized materials. However, the ultraviolet-polymerized sealant was more effective in preventing marginal leakage than the cold-curing sealants when applied as a covering over the restorations and extended onto the peripheral etched enamel.

Acid Etching, Dental↗
PubMed1977

Penetration of restorative resins into acid etched enamel. I. Viscosity, surface tension and contact angle of restorative resin monomers.

It has been a controversial question whether an intermediate layer of low-viscous, non-composite resin between composite restorative and etched enamel is beneficial. It was the purpose of the present work to investigate some of the factors that govern the penetration of resins into the capillary pores of etched enamel surfaces. Viscosity, surface tension and contact angle on human enamel were measured using monomer mixtures similar to those found in commercial restorative resins. Employing a cylindrical model of relevant dimensions of the capillary pores, and on the basis of Poiseuille's equation the time of penetration was calculated for a relatively high-viscous and a relatively low-viscous monomer mixture. It was concluded that viscosity as such is not a limiting factor for the penetration of restorative resin monomers into the pores of etched enamel surfaces.

Acid Etching, Dental↗
PubMed1977

Penetration of restorative resins into acid etched enamel. II. Dissolution of entrapped air in restorative resin monomers.

Viscosity, surface tension and contact angle are factors that influence the penetration of restorative resins into acid etched enamel. Furthermore, as the resin is drawn by the capillary forces into the pores of the etched enamel the pressure of the entrapped air will increase. The increased pressure has the effect that air will dissolve in a resin that is saturated with air at one atmosphere. The purpose of the present work was 1) to investigate the rate of dissolution of included air bubbles at increased pressure, 2) to use the results to calculate the depth of penetration by means of a cylindrical model of the capillary pores, and 3) to check the results of the calculations by measurements of the tag lengths of restorative resins placed on acid etched enamel. The rate of dissolution was measured in monomers of varying viscosity in a glass syringe by means of a stereo microscope. The calculations showed that the depth of penetration decreases only slightly with viscosity. Thin sections of restorative resins placed on acid etched enamel were prepared whereafter the enamel was dissolved in hydrochloric acid. Tag lengths of 50 micron or more were observed with composite as well as non-composite resins.

Acid Etching, Dental↗
PubMed1975

[Radio-restoration by yeast s-RNA and its nucleotides of plant tissues cultured in vitro. Restorative activity of yeast s-RNA and a mixture of its nucleotides on the growth of Sorconera crown-gall tissue cultures].

Gamma RNA extracts from yeast restore the growth of Scorsonere Crown gall tissues which were subjected to gamma radiation from sigma cobalt 60. A mixture of nucleotides obtained from enzymatic hydrolysis of s-RNA by a ribonuclease T1 has the same stimulatory effect.

Culture Techniques↗
PubMed2026

Marginal fit and five-year outcomes of posterior monolithic zirconia restorations: A randomized paired and observational clinical study.

OBJECTIVES: The aim of this study was to evaluate the marginal fit and five-year clinical performance of posterior 5 mol% yttria-partially stabilized zirconia restorations. A randomized paired comparison with lithium disilicate crowns was performed for marginal fit. METHODS: A total of 65 posterior restorations were placed in 38 patients, including 32 zirconia crowns, 17 lithium disilicate crowns, and 16 zirconia partial coverage restorations. In the randomized paired comparison, 17 patients received one lithium disilicate crown and one zirconia crown. Additional zirconia crowns (n=15) and zirconia partial coverage restorations (n=16) were included in a prospective observational cohort. The primary outcome was marginal fit within the randomized cohort. Marginal and internal fit were assessed using the replica technique. Marginal and internal gap values were compared using the Wilcoxon signed-rank test; clinical outcomes were analyzed descriptively, and Kaplan-Meier estimates were calculated for survival and complication-free survival. Clinical performance was assessed using CDA criteria, periodontal parameters, complication recording, and patient-reported outcomes. Clinical examinations were performed at baseline and at 12, 24, 36, 48, and 60 months. RESULTS: Mean marginal gap values at the crown margin were 46 ±33 µm for lithium disilicate crowns and 50 ±32 µm for zirconia crowns (p>0.05). No restoration required replacement, resulting in 100% restoration survival after a median follow-up of 60 months (range: 57-64 months). Most complications were biological or functional, including endodontic, periodontal, occlusal, and proximal-contact-related events. One zirconia partial coverage restoration exhibited a small ceramic fracture managed by polishing. The Kaplan-Meier probability of complication-free survival was 76.4% for zirconia crowns, 66.7% for lithium disilicate crowns, and 87.5% for zirconia partial coverage restorations. CONCLUSIONS: In the randomized paired comparison, 5 mol% yttria-partially stabilized zirconia crowns showed marginal gap values similar to lithium disilicate crowns. All restorations remained in situ during the observation period. Lower complication-free survival was mainly related to biological and functional events and should be interpreted separately from restoration survival. CLINICAL SIGNIFICANCE: Clinical evidence for posterior 5 mol% yttria-partially stabilized zirconia restorations remains limited. This study provides mid-term clinical data on crowns and partial coverage restorations. In the randomized full-crown comparison, marginal fit was similar to that of lithium disilicate crowns, supporting the clinical consideration of monolithic zirconia restorations for posterior teeth.

Humans↗
PubMed2026

Restoration contexts shape the bacterial and fungal soil communities in desertification hotspots in the Brazilian semiarid region.

Desertification in the Brazilian semiarid has compromised ecosystem functionality, impacting soil microbial biodiversity. Thus, restoration strategies have been implemented, aiming to mitigate the negative impacts. However, little is known about their effects on soil microbial communities. In this study, we hypothesized that the two restoration contexts would promote distinct trajectories of soil microbial community recovery. We evaluated 36 soil samples collected from two desertification hotspots in the Brazilian semiarid, representing active (Gilbués) and passive (Irauçuba) restoration contexts. Soil DNA was extracted and subjected to 16S and ITS amplicon sequencing to characterize bacterial and fungal communities, respectively. Community differences were assessed using alpha-diversity metrics, redundancy analysis (RDA), and PERMANOVA. The results showed that within Gilbués (active restoration), bacterial and fungal community composition differed among soils under desertification and restoration. In Irauçuba (passive restoration), only native soils differed from both soils under desertification and restoration. Proteobacteria, Actinobacteriota, and Firmicutes (bacteria), and Ascomycota and Basidiomycota (fungi), were the dominant phyla in both hotspots. Bacterial and fungal communities showed distinct taxonomic patterns among native, degraded, and restored soils within each restoration context. Niche occupancy patterns also differed between restoration contexts. In conclusion, the two hotspots followed contrasting microbial recovery trajectories, demonstrating that restoration responses are context-dependent and vary according to the microbial groups, rather than supporting the universal superiority of one restoration strategy over the other.

Soil Microbiology↗
PubMedDate not supplied

Assessment of dental restorative status.

Class I and Class II restorations on selected teeth of children aged 7-13 years were recorded in order to find which types of restorations were suitable for clinical evaluation of amalgam restorations with regard to frequency and anticipated observation period. Restorations suited for amalgam evaluation were found to be MO type restoration on all first molars and occlusal, palatal, and occlusal/palatal restorations on maxillary first molars and buccal pit restorations on mandibllar first molars. For the age group 7-11 years, the MO type restoration in the first molars will reflect the caries situation; the DO type restoration on maxillary first molars will serve this purpose for an age group approximately 2-4 years older. Thus selected recording of restorations must be considered age dependent in order to give a representative reflection of the caries experience. The most striking difference between the groups with high and low restoration frequency was a 2-year delay in the group with low frequency as compared with the group with high restoration frequency.

Adolescent↗
PubMed2026

Influence of endodontic access on the fracture resistance, retention and microleakage of full-coverage restorations in vitro: A systematic review and meta-analysis.

BACKGROUND: Endodontic access through retained full-coverage restorations (FCRs) is a preferred option for patients because of its high cost-effectiveness. However, the clinical performance of FCRs after repaired access cavity remains insufficiently characterized. This systematic review investigates the effects of endodontic access cavity preparation through retained FCRs on fracture resistance, retention, and microleakage based on in vitro studies. METHODS: A comprehensive search was performed in PubMed, Web of Science, and Scopus databases. Studies investigating the influence of endodontic access on the fracture resistance, retention, and microleakage of FCRs were included. Two independent reviewers conducted study selection, data extraction, and risk-of-bias assessment using the QUIN tool. Meta-analysis was employed to estimate fracture resistance and retention, with sensitivity analysis and subgroup evaluation also performed. Microleakage was summarized qualitatively. RESULTS: Twentythree studies were included: fracture resistance (n = 15), retention (n = 5), and microleakage (n = 3). Endodontic access significantly reduced fracture resistance for zirconia (p = 0.0002) and lithium disilicate (LD) restorations (p = 0.007), but not for resin-matrix ceramic (RMC) restorations (p = 0.25). Abutment tooth type contributed to heterogeneity within the LD and RMC subgroups. Retention was significantly reduced when access cavities were left unrepaired (p = 0.03), whereas appropriate repair protocols restored or enhanced retention relative to baseline. Accelerated aging increased microleakage in retained FCRs. Surface pretreatments and flowable resin liners tended to reduce microleakage, but findings were inconsistent. CONCLUSIONS: Endodontic access significantly reduces fracture resistance of zirconia and LD FCRs, whereas RMC restorations show no significant change. Appropriate repair protocols can restore or improve retention, potentially exceeding original values. Limited evidence suggests that effective sealing is achievable with appropriate materials. However, well-designed and in-vivo researches are needed to provide more detailed clinical guidance. CLINICAL SIGNIFICANCE: When performing endodontic access through retained FCRs, reduced fracture resistance must be carefully considered for zirconia and LD restorations, while RMC restorations may be exempt from this concern. Loss of retention with access can be restored after repair. Surface pretreatment and flowable resin liners help decrease microleakage.

Humans↗