Loss Of Anatomic Form Research Articles

The impact of extended pulp chamber preparations on the clinical performance of endocrowns in Indian patients: A 1-year observational study

PurposeThe limitations of foundation restorations have been reduced with the advent of endocrowns. Despite their success, the extent of endocrowns tooth preparation into the pulp chamber has not been fully explored in the literature. The study aimed to evaluate the clinical performance of endocrowns with 5 mm extended pulp chamber tooth preparations in Indian patients over a 1- year period using modified USPHS criteria. MethodsThe observational study recruited 36 participants with definite criteria. Ceramic crown was planned for all the participants. Conventional endocrown tooth preparation was made with 5 mm pulpal extension. Clinical assessments were made at 0-, 6- and 12-months intervals using modified USPHS criteria. The data was statistically analyzed using Friedman test and Wilcoxon signed rank test. ResultsOne patient (2.8%) experienced loss of retention, marginal adaptation, and loss of anatomical form during 1-year follow up period. The majority of the participants (97.3%) reported no discomfort and high satisfaction. (P < .05) No opposing tooth wear was observed at 0- and 6-months. The results showed statistical significance in the parameters of retention, marginal adaptation, loss of anatomical form, and patient satisfaction. (P < .05). ConclusionThe clinical performance of endocrowns with extended pulp chamber preparation was satisfactory for a period of 12 months.

Clinical performance of high-viscosity glass ionomer and resin composite on minimally invasive occlusal restorations performed without rubber-dam isolation: a two-year randomised split-mouth study.

The aim of this clinical trial was to evaluate the 2-year clinical performances of high-viscosity glass ionomer and nanohybrid resin composite restorations performed without rubber dam isolation. Occlusal carious lesions on the right and left mandibular second molars of 56 patients (26 female, 30 male patients) were restored in a split-mouth design. High-viscosity glass ionomer (Hv-GIC) (Equia, GC) and nanohybrid resin composite (GrandioSO, Voco) were used as restorative materials. Clinical evaluations of the restorations were performed according to the Fédération Dentaire Internationale criteria. Data were analysed using the Friedman's analysis of variance and Mann-Whitney U tests (α=0.05). After 2 years, the success rate of Hv-GIC restorations was 96% and that of resin composite restorations was 100%. Hv-GIC showed lower marginal discoloration and greater surface wear and loss of anatomic form (p<0.05). Resin composite showed significantly better surface lustre. The 2-year performance of resin composite was similar to that of Hv-GIC for the occlusal restorations of mandibular second molars, in spite of being performed without rubber-dam isolation. Saliva contamination can be a clinically significant problem for dental restorations. High-viscosity glass ionomers are a satisfactory alternative to resin composites with the advantage of fast application in such situations. Clinical Trials Registration number-date: NCT04488380-22/07/2020, retrospectively registered.

CLINICAL EVALUATION OF THE NANO HYBRID BULK FILL COMPOSITE AND NANO HYBRID FLOWABLE COMPOSITE IN CLASS I RESTORATIONS--- AN IN VIVO STUDY

Objectives: The aim of this study was to evaluate the clinical performance of a nano filled flowable and nano hybrid bulk fill resin composite in class I restorations.&#x0D; Methods and Materials: Twenty patients were selected for this in vivo study. Each patient received at least one pair of restorations, restored with nano hybrid bulk fill resin composite (IPS Empress direct [IED]) and nano hybrid Tetric N Ceram flowable composite [TNC]. Each restorative resin system was used with its respective adhesive system according to manufacturers’ instructions.&#x0D; A total of 40 class I restorations were placed by one operator. Restorations were blindly evaluated by two examiners at baseline and 3, 6, and 12 months respectively using modified US Public Health Service Ryge criteria.&#x0D; The data obtained was statistically analyzed using Chi square test to compare the two restorative materials for each category.&#x0D; Results: At 3, 6 and 12, months, recall rate was 100%, 95% and 85%, respectively, with a retention rate of 100%. There were statistically significant differences between the two restorative resins in terms of marginal adaptation and marginal discoloration (p&lt;0.05).&#x0D; No differences were observed between the restorative resins in terms of retention (p&lt;0.05). None of the restorations showed postoperative sensitivity, or loss of anatomic form.&#x0D; Conclusion: Within the limitations of this study, nano hybrid bulk fill composite resin viz. IPS EMPRESS DIRECT showed better clinical performance than nano filled flowable composite in terms of marginal discoloration and marginal adaptation.&#x0D; Keywords: direct composite, bulk, hybrid filled resin

Microhybrid versus nanofill composite in combination with a three step etch and rinse adhesive in occlusal cavities: five year results.

ObjectivesThe aim of the study was to evaluate the 5-year clinical performance of occlusal carious restorations using nanofill and microhybrid composites, in combination with 3-step etch-and-rinse adhesives, in patients who were going to commence orthodontic treatment.Materials and MethodsA total of 118 restorations for occlusal caries were conducted prior to orthodontic treatment. Occlusal restorations were performed both with Filtek Supreme XT (3M ESPE) and Filtek Z250 (3M ESPE) before beginning orthodontic treatment with fixed orthodontic bands. Restorations were clinically evaluated at baseline and at 1, 2, 3, 4, and 5-year recalls.ResultsNone of the microhybrid (Filtek Z250) and nanofill (Filtek Supreme XT) composite restorations was clinically unacceptable with respect to color match, marginal discoloration, wear or loss of anatomical form, recurrent caries, marginal adaptation, or surface texture. A 100% success rate was recorded for both composite materials. There were no statistically significant differences in any of the clinical evaluation criteria between Filtek Z250 and Filtek Supreme XT restorations for each evaluation period.ConclusionsThe composite restorations showed promising clinical results relating to color matching, marginal discoloration, wear or loss of anatomical form, recurrent caries, marginal adaptation, and surface texture at the end of the 5-year evaluation period.

Nine-year clinical evaluation of composite resins in Class III restorations

Objective: The aim of this study was to evaluate the nine-year clinical performance of Class III composite restorations using two microhybrid anterior composite resins [Magic™-Vigodent/(F) and Z100™-3M ESPE/(Z)]. Material and Methods: The study was a randomized controlled trial, following the split mouth design. Seventy restorations were placed, thirty-five for each resin composite into 35 patients. The restorations were placed by one operator according to the manufacturers’ specifications. Two independent evaluators conducted the clinical evaluation using modified USPHS criteria. After nine-years, 56 restorations (28F-28Z) were evaluated. Data were analyzed using Chi-square, Exact Fisher and McNemar tests (p&lt;0.05). Results: No postoperative sensitivity, secondary caries and loss of anatomic form was observed after nine-years for both composites. There were no significant differences between the two composites tested at baseline and after nine-years. Significant differences for Z and F restorations between baseline and nine-year with respect to color matching and for F regarding the marginal integrity were detected. Conclusion: The clinical performance of both materials was considered acceptable after the 9-year evaluation.

Clinical evaluation of different adhesives used in the restoration of non‐carious cervical lesions: 24‐month results

The aim of this study was to compare after 24 months the clinical performance of cervical restorations placed with the use of an etch-and-rinse and an all-in-one adhesive. Twenty-four patients with at least one pair of non-carious cervical lesions participated in this study. One hundred and twenty-three cervical lesions were restored (62 etch-and-rinse adhesive, Solobond M; 61 all-in-one adhesive, Futurabond NR). A nanohybrid resin composite, Grandio, was used as the restorative material. Restorations were evaluated according to modified USPHS criteria by two independent examiners. The survival rates of the restorations were calculated by the Kaplan-Meier estimator and log-rank test. The restorations in each category were compared using the Pearson chi-square test, while the performance of restorations at the baseline and at each recall time was evaluated by McNemar's test (p < 0.05). The recall rate of patients was 100%. The retention rates were 82% and 75% at 6 months and 77% and 62% at 12 months for Solobond M and Futurabond NR, respectively. At the 24-month recall, the retention rate was 69% for Solobond M and 49% for Futurabond NR, and this difference was statistically significant (p < 0.05). No statistically significant difference was found for colour match, marginal staining, or marginal adaptation between the adhesives (p > 0.05). None of the restorations had secondary caries, loss of anatomical form, or surface texture changes. Cervical restorations placed with an etch-and-rinse adhesive showed higher retention than an all-in-one adhesive.

Clinical effectiveness of direct class II restorations - a meta-analysis.

More than five hundred million direct dental restorations are placed each year worldwide. In about 55% of the cases, resin composites or compomers are used, and in 45% amalgam. The longevity of posterior resin restorations is well documented. However, data on resin composites that are placed without enamel/dentin conditioning and resin composites placed with self-etching adhesive systems are missing. The database SCOPUS was searched for clinical trials on posterior resin composites without restricting the search to the year of publication. The inclusion criteria were: (1) prospective clinical trial with at least 2 years of observation; (2) minimum number of restorations at last recall = 20; (3) report on dropout rate; (4) report of operative technique and materials used; (5) utilization of Ryge or modified Ryge evaluation criteria. For amalgam, only those studies were included that directly compared composite resin restorations with amalgam. For the statistical analysis, a linear mixed model was used with random effects to account for the heterogeneity between the studies. P-values under 0.05 were considered significant. Of the 373 clinical trials, 59 studies met the inclusion criteria. In 70% of the studies, Class II and Class I restorations had been placed. The overall success rate of composite resin restorations was about 90% after 10 years, which was not different from that of amalgam. Restorations with compomers had a significantly lower longevity. The main reason for replacement were bulk fractures and caries adjacent to restorations. Both of these incidents were infrequent in most studies and accounted only for about 6% of all replaced restorations after 10 years. Restorations with macrofilled composites and compomer suffered significantly more loss of anatomical form than restorations with other types of material. Restorations that were placed without enamel acid etching and a dentin bonding agent showed significantly more marginal staining and detectable margins compared to those restorations placed using the enamel-etch or etch-and-rinse technique; restorations with self-etching systems were between the other groups. Restorations with compomer suffered significantly more chippings (repairable fracture) than restorations with other materials, which did not statistically differ among each other. Restorations that were placed with a rubber-dam showed significantly fewer material fractures that needed replacement, and this also had a significant effect on the overall longevity. Restorations with hybrid and microfilled composites that were placed with the enamel-etching technique and rubber-dam showed the best overall performance; the longevity of these restorations was similar to amalgam restorations. Compomer restorations, restorations placed with macrofilled composites, and resin restorations with no-etching or self-etching adhesives demonstrated significant shortcomings and shorter longevity.

Clinical evaluations of resin-modified glass-ionomer restorations

This paper collates some of the existing data on the clinical evaluations of resin-modified glass-ionomer cements (RMGICs) since their introduction two decades ago. The relevant literature was considered and data reviewed under the headings of retention, marginal characteristics, material deterioration, secondary caries, color stability, as well as pulpal and biological effects. The retention for RMGICs is generally good, with an annual failure rate over 13 years reported as being under 3%. However, more data is required on their performance in carious situations. Regarding marginal characteristics, they exhibit margins that are likely to deteriorate over time. From the limited data on the surface characteristics, they appear to exhibit some wear and loss of anatomic form, particularly in the mid to long term. Despite the fact that the studies reviewed for secondary caries varied in the initial caries status of lesions restored, the overwhelming conclusion is that this does not seem to be a problem. While their initial color match may be favorable, it appears that they change over time and may not be color stable. In the absence of more clinical data, it is difficult to draw conclusions on the pulpal and biological effects. The existing information primarily reports postoperative sensitivity, which fortunately does not seem to be an issue with RMGICs, and limited histopathology of the pulp, with mixed opinions. The RMGICs appear to perform well in terms of retention, and secondary caries as well as postoperative sensitivity are not a problem. However, this is not necessarily true of their marginal characteristics, surface properties and color stability. More and long-term clinical research is required to establish compelling evidence of their behavior, particularly in terms of retention in carious cavities, surface properties and biological effects.

Clinical evaluation of a polyacid-modified resin composite (Dyract) in class V carious lesions: 5-year results

This study evaluated the 5-year clinical performance of polyacid-modified resin composite, Dyract (DeTrey/Dentsply, Konstanz, Germany), restorations in class V carious lesions. Ninety-two class V carious lesions in 28 patients were restored with Dyract. Restorations were clinically evaluated at baseline, 1-, 2-, 3-, 4-, and 5-year recalls and were evaluated according to the modified Ryge criteria by two experienced calibrated examiners in regard to color match, marginal discoloration, wear or loss of anatomical form, caries, marginal adaptation, and surface texture. The retention rate after 5 years compared to baseline in class V carious restorations was 84%, with only 12 restorations failing. Color change and marginal discoloration in restorations were found to be statistically significant (p = 0.0238 and p < 0.0001, respectively) at the end of the 5 years, but did not require replacement of any of the restorations. The results of this study revealed that at the end of 5 years, Dyract exhibited a clinically acceptable success rate but had significant color changes and marginal discoloration in class V carious lesions.

An overview of reasons for the placement and replacement of restorations.

Surveys on reasons for the placement and replacement of restorations have been conducted in various countries. The purpose of this paper is to bring together and review the data of 10 such surveys with similar methodology. The studies reviewed are all based on the protocol described by Mjör in 1981. The surveys reviewed provide data on the reasons for the placement and replacement of a total of 32,777 restorations. Notwithstanding differences between countries, different groups of practitioners and minor variations in methodology, the data included in the selected surveys indicate that everyday clinical practice in Scandinavia, UK and USA during the 1980s and 1990s has involved more replacement than initial restorations, with the ratio of initial to replacement restorations ranging from 1:1.1 to 1:2.4 for amalgam and 1:1.1 to 1:3.8 for composite materials. Primary caries has been consistently found to be the principal reason for the provision of initial restorations of amalgam and composite. The principal reason for the replacement of restorations of amalgam and composite has remained secondary caries as diagnosed clinically. Material failures (marginal degradation, discoloration, bulk fracture and loss of anatomic form) accounted for the replacement of more restorations of composite than amalgam. Recent surveys have reported secondary caries as the principal cause of failure of restorations of glass-ionomer cements and related materials. The clinical diagnoses of caries may continue to be found to account for the placement and replacement of most intracoronal restorations. Surveys of the type reviewed provide valuable insight into patterns of provision of dental care and highlight research priorities in relation to direct restorations.

Clinical evaluation of Dentacolor as a posterior veneering agent.

A growing number of clinicians have been using laboratory light‐cured resins as a substitute for porcelain veneers. These new systems offer a number of advantages over porcelain. In addition to possessing the ability of being repaired or modified directly in the oral cavity, they can be used with virtually any alloy. This two‐year study dealt with the clinical evaluation of Dentacolor as a veneering agent on posterior crowns. Forty restorations were inserted into a series of patients and evaluated for the following characteristics: color matching ability, wear or loss of anatomic form, surface texture and microleakage at the veneer‐metal interface. At the end of the two years the average wear was only 22 μm. Furthermore, the wear rate was linear. The surfaces were free from pitting, retained a high luster, and exhibited excellent color matching ability.

Current Developments in Posterior Composite Resins

The use of posterior composite resins has grown at a rapid rate. While the original materials were completely inadequate for the restoration of Class I and II cavity preparations, the newer-generation materials are apparently superior. While wear rates of over 100 μm per year were not uncommon, some of the newer composites wear away at the rate of less than 1 μm per month. A great deal of the improvement in wear resistance can be attributed to an optimization of the filler particle. Specifically, the particle size has been decreased and the filler loading has been increased. In some instances, softer filler particles have been incorporated in order to decrease the hardness differential between the filler and the resin matrix. Other factors which have been considered include chemical erosion of the matrix, degradation of the silane coupling agent, internal porosity, method of polymerization, and hydrophobicity of the resin matrix. A greater understanding has been developed regarding patterns of wear as well as rates of wear. Techniques have been developed for rapid and routine measurements of the loss of anatomical form. Although the composite resins have been improved substantially, their use in posterior teeth is quite technique-sensitive. Furthermore, the problem of secondary caries is still a major concern.

Two-year clinical study of composite resins in posterior teeth.

Abstract Lack of resistance to abrasion and loss of anatomic form have characteristically been attendant problems of first generation composite resins placed in posterior teeth. Variations in method of polymerization, filler content, particle size, and particle composition have been attempted to improve clinical characteristics. The purpose of this study was to evaluate the clinical performance of 5 different composite resins placed in Class I and Class II preparations. All restorations were evaluated directly using USPHS criteria. Indirect evaluations of the restorations on diestone casts were made to categorize quantitatively the amount of occlusal wear. No statistically significant differences among the materials regarding wear were observed when using USPHS criteria. However, statistically significant differences in the results detected by indirect evaluation suggest that loss of anatomic form may be related to the size and composition of the filler particles in the resin restorative materials.