PubMed HealthSearch

SEARCH · PubMed Health

Results for “Dental Marginal Adaptation”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original 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

Early prediction of long-term margin adaptation of dental amalgam restorations.

The present study assessed the predictive value of an indirect metric method for the early detection of margin defects of amalgam restorations, relative to results using a direct clinical method. The material consisted of plaster casts of amalgam restorations taken at 1- and 2-yr examinations of four different amalgam-treatment combinations. The widest margin defect of each restoration was measured in a dissection microscope equipped with a metric scale in the ocular. The ranking order obtained from the metric measurements of the different amalgam-treatment combinations after 1 and 2 yr was compared with that obtained from the direct clinical evaluation after 2 yr. Finally, the rank order of those restorations rated Alfa (no visible evidence, along the margin, of a crevice (ditch) into which an explorer will penetrate) at the 2-yr clinical examination was studied in relation to the 1-yr metric measurements. For the total material, the rank order based on the metric measurements of the margin defects of the four amalgam-treatment combinations agreed with that obtained with the clinical rating. In the 1-yr data, where the metric technique was applied only on the restorations rated Alfa at the 2-yr clinical evaluation, the order of two neighboring combinations was reversed; otherwise the same rank order was obtained. It is recommended that the clinical performance of new brands of amalgam alloy are tested in short-term, small-scale studies using the metric evaluation technique, before more extensive field studies over longer periods are instituted, in order to sort out unsatisfactory materials and treatment techniques at an early stage.

Child

Clinical Performance of Bulk-Fill Versus Incremental Composite Placement Approaches in Vital Posterior Teeth: A 24 Months Randomized Controlled Trial.

BACKGROUND: Composite resin placement technique may influence marginal integrity, polymerization stress distribution, and long-term clinical performance of posterior restorations. This randomized controlled clinical trial evaluated the 24-month clinical performance of four different placement techniques in Class I posterior composite restorations. METHODS: Fifty patients aged 20-35&#x2009;years presenting with four occlusal carious lesions each were enrolled, resulting in 200 restorations. Cavities (4-5&#x2009;mm depth) were prepared according to caries extension. Restorations were randomly allocated into four equal groups (n&#x2009;=&#x2009;50) according to placement technique: stamp technique, snowplow technique, modified incremental "pizza" technique, and bulk-fill technique. All materials were applied following manufacturers' instructions. Clinical evaluation was performed at baseline and after 6, 12, and 24&#x2009;months using FDI criteria. Functional (fracture/retention, marginal adaptation), esthetic (marginal staining, anatomical form), and biological (postoperative sensitivity, secondary caries) properties were assessed by two calibrated evaluators. Statistical analysis was performed at a significance level of &#x3b1;&#x2009;=&#x2009;0.05. RESULTS: Thirty-eight patients with a total of 152 restorations were evaluated at the end of the 24&#x2009;months in line with FDI at the end of the study with 76% recall rates. No statistically significant differences were observed among groups regarding fracture/retention or secondary caries (p&#x2009;>&#x2009;0.05). Marginal adaptation and marginal staining demonstrated minor deterioration over time across all groups, with statistically significant intergroup differences found (p&#x2009;<&#x2009;0.05). Postoperative sensitivity was minimal and transient in all groups with no significant difference (p&#x2009;=&#x2009;0.181). CONCLUSIONS: Within the limitations of this 24-month follow-up, the four placement techniques demonstrated comparable clinical performance in Class I posterior composite restorations. Selection of technique may therefore be guided by clinical preference and procedural efficiency rather than differences in short-term clinical outcomes. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT07415317.

Humans

Marginal adaptation and seal of direct and indirect Class II composite resin restorations: an in vitro evaluation.

The aim of this in vitro study was to evaluate the marginal adaptation and seal of posterior composite resin restorations made with direct (three-sited multilayering) or indirect (extraoral inlay) techniques. The influence on the marginal quality of the cervical finishing design (butt or beveled) and residual enamel height (0.5, 1.0, and 1.5 mm up to the cementoenamel junction) was also evaluated. This trial was performed on sound, freshly extracted human molars. When residual enamel was less than 1.0 mm in height or 0.5 mm in thickness, indirect restoration resulted in superior marginal quality. For preparations with sufficient residual enamel height (greater than 1.0 mm), beveling of gingival margins appeared mandatory for good adaptation of direct restorations and beneficial to the adaptation of indirect restorations. Residual gingival enamel height and thickness demonstrated an influence on marginal quality only in indirect restorations with butt margins.

Acrylic Resins

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 &#xb1;33 &#xb5;m for lithium disilicate crowns and 50 &#xb1;32 &#xb5;m 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

Marginal adaptability and fit of ceramic milled inlays.

The authors investigated the marginal adaptation and internal fit of ceramic inlay made by a ceramic milling system. The study's results indicated that the mean marginal and internal gap size of the ceramic inlay restorations was less than 100 microns, making the fit clinically acceptable.

Computer-Aided Design

In vitro marginal adaptation of alumina porcelain ceramic crowns.

This study evaluated the dimensional stability during firing of In-Ceram alumina porcelain ceramic and examined the marginal fit for three different configurations of tooth preparation. A stereomicroscope was used to measure the space between the margin of restorations and tooth preparations. The three methods of tooth preparation were statistically compared and revealed suitable dimensional stability during the firing and glazing process. A better marginal fit was recorded for artificial crowns fabricated on a chamfer or 50-degree shoulder tooth preparation.

Aluminum Oxide

Marginal breakdown of fired ceramic inlays cemented with glass polyalkenoate (ionomer) cement or resin composite.

The marginal breakdown of fired porcelain inlays in vivo, luted with either a dual-cured resin composite or a glass polyalkenoate(ionomer) cement, was evaluated by scanning electron microscopy. Immediately following polishing (baseline) and after 1 year, replica impressions were made of the occlusal and proximal margins of two inlays, one cemented with the resin composite and the other with the glass ionomer cement, in each of 12 patients. At baseline the best marginal adaptation was observed along the proximal margins of the composite luted inlays, while occlusally glass ionomer luted inlays showed better marginal qualities than the composite luted inlays. At 1 year the composite luted inlays showed significantly better marginal adaptation than the glass ionomer luted ones at all interfaces. The greatest breakdown was observed occlusally, especially in the glass ionomer luted inlays. Gap sizes varied proximally between 83 and 100 microns and occlusally between 107 and 143 microns. Severe ditching was observed occlusally in the glass ionomer luted inlays. The overall marginal quality was significantly better for the inlays luted with the resin composite both at baseline and after 1 year.

Analysis of Variance

Mastique laminate veneers: results after 4 and 10 years of service.

The purpose of the present study was to evaluate the clinical quality over 4 years and the longevity over 10 years of 77 Mastique laminate veneers (DeTrey, Dentsply). The veneers were bonded to incisors and canines with a light-cured composite resin, using the acid-etch technique, and examined every 1/2 year in accordance with USPHS criteria. Anatomic form and marginal adaptation were rated excellent in more than 50% of the veneers throughout the study. Moderate surface wear was seen in most of the veneers after 4 years of service. Marginal discoloration and color match were recorded as not acceptable in 20% of the veneers at the 4-year control. No significant difference was found in the gingival index between veneer and control teeth. The cumulative retention rate was 40% after 4 years and 20% at the 10-year recall. Owing to the high frequency of spontaneous loss, Mastique laminate veneers cannot be recommended as permanent restorations.

Acid Etching, Dental

Influence of light intensity on two restorative systems.

OBJECTIVES: High intensity curing lights are recommended almost universally on the basis of immediate curing depth measurements. Although this single factor is well documented, the influence of light intensity on other parameters has not been investigated extensively. METHODS: Two restorative systems were examined with two light intensities in regard to four properties; polymerization shrinkage (density method), flexural modulus and strength (ISO 4049), hardness profiles after post-cure (Vickers), and marginal adaptation in dentine cavities (quantitative margin analysis). RESULTS: The variation in light intensity did not significantly affect curing contraction or post-cure hardness profiles to a depth of 4.5 mm for either resin composite. Significant differences were found in flexural modulus with both restoratives; only one material demonstrated a light intensity-related influence on flexural strength. Marginal gap formation increased in each bonding agent/resin composite pair with increased light intensity. CONCLUSION: In clinically relevant layer thicknesses, curing a resin composite with a higher intensity light may demonstrate significant disadvantages due to increased shrinkage stress.

Animals

A comparison of the marginal and internal adaptation of titanium and gold-platinum-palladium metal ceramic crowns.

The marginal and internal adaptation of metal ceramic crowns fabricated by electrical discharge machining and conventional metal ceramic alloys were compared. The crowns were cemented using zinc phosphate cement, embedded in epoxy resin, and sectioned in two planes: diagonal and buccolingual. The crowns were then measured at nine sites. The results showed that there were no statistical differences between the external marginal opening of the titanium and the gold-platinum-palladium crowns. The overall marginal discrepancies for the restorations in this study were 61 microns (+/- 34 microns) for the titanium metal ceramic crowns and 47 microns (+/- 17 microns) for the gold-platinum-palladium metal ceramic crowns.

Analysis of Variance

Effect of dimension of luting space and luting composite on marginal adaptation of a class II ceramic inlay.

This study evaluated the in vitro marginal quality at the interproximal cervical margin of class II Cerec restorations. Marginal quality was evaluated separately by (1) SEM analysis before and after simultaneous thermocycling and mechanical loading for the integrity of the restoration surface and (2) dye penetration after thermocycling and mechanical loading to evaluate the strength of the bond within the depth of the cavity. The results reveal that marginal integrity is influenced by the width of the luting space and the luting composite. With a luting space of 100 microns, marginal quality with as little as 3% to 14% loss of adhesion can be obtained. Luting spaces greater than 100 microns can partially be compensated by the luting composite. For Cerec inlays, highly filled luting composites with a high viscosity are recommended.

Adhesiveness

Assessment of marginal stability and permeability of an interim restorative endodontic material.

The purpose of this study was to assess the marginal stability and permeability of a new interim restorative endodontic material, Tempit (Centrix Inc., Milford, Conn.), and to compare the findings with the results of two commonly used restorative endodontic materials, Cavit (Premier Dental Products Co., Philadelphia, Pa.) and IRM (Intermediate Restorative Material Capsules, The Caulk Co., Division of Dentsply International Inc., Milford, Del.) This study was performed in several steps. First, the endodontic access cavities were prepared and restored on 80 extracted mandibular molars. The samples were exposed to methylene blue dye solution for 6 days, thermocycled, and sectioned; the dye penetration and diffusion were measured along the margins and into the body of the materials. The second experiment was a special study performed in standardized glass tubes to better evaluate the marginal and body dye penetration into the materials by increasing the length of the fillings. To eliminate the possibility of hygroscopic setting mechanisms of materials, samples were first allowed to set under water before dye was introduced. Cavit and Tempit showed a substantial amount of dye diffusion into the body of the materials. Cavit exhibited the best sealing ability at all times. The marginal and body dye penetration were significantly different for the Tempit material in all experiments than Cavit (p < 0.001). IRM demonstrated the least body penetration of all three materials (p < 0.001) but had a substantial marginal leakage not significantly different from the results of the Tempit material (p = 0.6 and p = 0.1).(ABSTRACT TRUNCATED AT 250 WORDS)

Analysis of Variance

Microleakage of resin-modified glass ionomer cement restorations: an in vitro study.

Microleakage of two resin-modified glass ionomer cement (GIC) restorative materials was compared with that of two conventional GIC restorative materials. Forty-five noncarious extracted human molars were prepared with standardized Class V cavity outlines on the buccal and lingual surfaces. The occlusal margin was in enamel and the gingival margin was in dentin/cementum. All were restored according to the manufacturers' instructions. After thermocycling, 30 teeth were placed in 2% basic fuchsin dye for 24 h, sectioned and viewed with a stereomicroscope to assess microleakage. The other 15 teeth were sectioned, replicated and prepared for marginal gap evaluation using a SEM. Differences in microleakage scores between materials were compared using Kruskal-Wallis and Mann-Whitney U tests. One resin-modified GIC restorative material showed significantly less microleakage against enamel and dentin/cementum compared to the conventional GIC restorative (p < 0.01). Marginal gap formation for both resin-modified GIC restorations was limited to the axial wall of the restorations.

Analysis of Variance

Confirmation of Leinfelder clinical wear standards.

OBJECTIVES: Accuracy of composite wear studies based on Leinfelder standards has been disputed. There are differences with other well-calibrated systems such as the M-L and Vivadent wear standards. The objective of this study was to reevaluate the margin height at key regions along the restoration margins for each of the 6 Leinfelder standards using laser profiling techniques. METHODS: The Leinfelder standards were profiled in parallel paths 100 microns apart and measured in x-y-z position every 20 microns along those paths using a laser profilometer. RESULTS: Rounding of cavosurface enamel margins from intraoral wear greatly increased the uncertainty of the true enamel margin location and step height measurements, precluding unequivocal measurements for standards #2 and #3. Values for other standards for the original report, newly measured means and standard errors, and measured ranges were: #4 (322 microns, 333 +/- 34 microns, 171-507 microns), #5 (382 microns, 459 +/- 44 microns, 202-649 microns), and #6 (493 microns, 584 +/- 91 microns, 315-1022 microns). There were no statistically significant differences (p < or = 0.10) between these and original values. Large standard errors may have obscured small differences that may exist. The Leinfelder cast conversion scale seems to be the correct relative magnitude. SIGNIFICANCE: Differences between Leinfelder casts and other standards may be due to differences in shadow production. Clinical wear may be systematically underestimated by other cast evaluation methods that have well-defined margins. This emphasizes the need for standard casts with margin morphology similar to the clinical casts being evaluated for wear.

Bicuspid

New adhesives in Class V restorations under combined load and simulated dentinal fluid.

OBJECTIVES: This study compared the efficacy of three dentinal adhesives using the "all etch" technique (All-Bond 2, Bisco; Scotchbond MP,3M Dental Products Co.; OptiBond, Kerr) with a dentinal adhesive which still uses phosphoric acid to condition enamel and a self-etching primer for dentin (A.R.T.-Bond, Coltene/Whaledent). METHODS: Eight V-shaped mixed Class V restorations were placed per group in extracted human premolars. The restorations were subjected to 1,200,000 mechanical occlusal cycles (max. force 49 N; frequency 1.7 Hz) and 3,000 simultaneous thermal cycles (5-50-5 degrees C). Dentinal fluid was simulated using 1:3 diluted horse serum and fed into the pulp chamber both during restoration and loading. Percentages of "continuous margin" were assessed on SEM replicas of enamel and dentinal margins at 200x magnification immediately before and after stressing, respectively. RESULTS: No significant differences were observed before stress between the materials either in enamel or in dentin. After stress, however, OptiBond and A.R.T.-Bond performed significantly better in dentin than the two other adhesives (Kruskal-Wallis, Mann-Whitney; p < 0.05). Although high initial values were observed, All-Bond 2 and Scotchbond MP were not stress-resistant under simulated physiological conditions. SIGNIFICANCE: The predicted clinical potential of All-Bond 2 and Scotchbond MP is inferior to that of OptiBond and A.R.T.-Bond.

Acid Etching, Dental

The effect of dentin bonding agents on the microleakage of porcelain veneers.

OBJECTIVES: This in vitro study was conducted to investigate the effect of dentin bonding agents on the microleakage of porcelain veneers cemented on dentin margins. METHODS: Forty human premolars were prepared on both the buccal and palatal surfaces. Each half was randomly assigned to eight groups. The veneer preparation of one group was cut entirely within enamel, to serve as controls. The remaining groups had cervical margins extending 1 mm beyond the cemento-enamel junction. Six dentin bonding agents were tested. The specimens were subjected to thermocycling and evaluated for marginal leakage using a silver nitrate stain technique. After sectioning, the extent of microleakage was measured at four interfaces: (1) incisal porcelain-composite; (2) incisal tooth-composite; (3) cervical porcelain-composite; and (4) cervical tooth-composite. RESULTS: Statistical analysis showed that the cervical tooth-composite interface had a significantly higher leakage value (p < 0.05) than the other three interfaces when the cervical margins were in dentin. SIGNIFICANCE: The dentin bonding agents tested did not significantly reduce the marginal leakage of the porcelain veneers cemented on dentin margins.

Analysis of Variance

Thermocycling and dwell times in microleakage evaluation for bonded restorations.

OBJECTIVES: To answer criticisms of an insufficient number of cycles in thermocycling in an earlier paper (Wendt et al., 1992), this study was initiated to evaluate the effect of different dwell times during long-term thermocycling in microleakage analysis of bonded restoratives. METHODS: A total of 90 resin-bonded restorations, Tytin/Liner F, (Kerr/Bisco), APH/Universal Bond 3, (LD Caulk) and Heliomolar/Syntac, (Vivadent), were inserted in Class V preparations in human third molars. Group A restorations were stored in 0.5% basic fuchsin dye for 166 h. Group B restorations were thermocycled for 5000 cycles in 0.5% basic fuchsin dye baths at 5 +/- 1 degrees C and 55 +/- 1 degrees C with a dwell time of 10 s in each bath. Group C was thermocycled as in Group B but with a dwell time of 60 s. Readings by defined criteria were taken from each of two 1 mm sections along the cemental margin. RESULTS: There were no significant differences (p < 0.05) in the extent of dye penetration at the tooth restoration interface for the thermocycled composite restorations when compared to composite restorations with no thermocycling. There was a significant difference (p < 0.05) in the extent of dye penetration at the tooth restoration interface for the thermocycled amalgam restorations when compared to dye-exposed amalgam specimens with no thermocycling. SIGNIFICANCE: During microleakage analysis, the need for thermocycling is dependent upon the extent the restorative is thermally conductive in relation to its mass. The dwell time should be clinically relevant, i.e., 10 s, and is important only if the restorative is thermally conductive.

Acrylic Resins