The results of our study show the same trends although the relative proportions differ. Within this study even after allowing for differences between practitioners , restoration failure rate increased with age of the patients. The effect of age on restoration longevity has been identified in other studies 29 , 30 involving restorations in different locations on teeth, but the reason for this has not been established. NCCLs may have been present for longer in older patients increasing the degree of dentine sclerosis present and reducing the ability to bond to these lesions.
It may simply be related to the size of the lesions, since it was established that increasing cavity size was associated with a shorter time to failure and also that there was a positive correlation between increasing patient age and increasing cavity size. Age-related changes in the structure of teeth may also be a factor. Over time, dentine tubules decrease in diameter and number 32 with an associated decrease in permeability, 33 water content 34 and altered mechanical properties of dentine.
In the first Cox regression model, restorations in cavities extending across both enamel and dentine survived longer than those confined to dentine. Enamel is a more reliable substrate to which to bond and where an adhesive material can be extended across an area of enamel, better retention would be the expected result.
This effect, which reached a significant level in the two-year data, becomes more evident after five years where the survival plots show a reduced time to survival of restorations placed into dentine cavities.
There is much debate and interest among clinicians as to which is the 'best' restorative material for different situations. Indeed, one of the principle aims of this study was to try to identify which material should be recommended for restoring Class V cavities. RMGI restorations performed well over five years in comparison with the other tooth-coloured materials, which concurs with the findings of other studies of similar duration.
For cavities where caries was not the cause, the practitioner had a greater influence on survival than the choice of material. The preparation of the cavity also exerted a significant effect on survival. Preparation using a rotary bur significantly increased the time to failure of NCCLs. With hindsight, it would have been desirable to record what extent of preparation with a bur had been carried out, as this could have ranged from a simple roughening of the surface to the creation of a macro-retentive cavity.
As these lesions required no removal of diseased tissue, it is more likely that only surface roughening had been performed. Despite the success reported in some studies where a 'no preparation' approach had been followed, 15 a recent meta-analysis 36 also identified the positive effect on Class V restoration survival associated with roughening of the cavity base.
Although the strength of evidence on restoration material presented here is limited, it does suggest that the apparent ease of use of conventional glass ionomer may not predictably translate into the production of a durable restoration and that a more careful placement technique, including appropriate cavity preparation, is needed. Occlusal factors are considered by many to be important in the aetiology of NCCLs 40 , 41 , 42 and in the success of restorations. The issue of elastic modulus is somewhat complicated as materials within one classification may have quite distinct mechanical properties and so it cannot necessarily be assumed, for example, that all composites have a significantly higher elastic modulus than all RMGIs.
When compared with the findings of our previous analysis conducted after two years, the results have suggested that most of the factors influencing the time to failure across five years were the same as the factors identified as influencing the probability of failure within two years of placement, 22 although the rate of failure was not consistent over the five years.
Increasing cavity size did not appear to affect two-year failure but reduced the time to failure of restorations over five years. This may be because larger cavities can have a longer margin or that filling a bigger cavity requires more skill, but as stated previously, cavity size is also linked to patient age and thus possible changes in the dentine.
Overall, at least The time to failure of Class V restorations placed by this group of dentists was reduced in association with the individual practitioner, smaller cavities, glass ionomer restorations, moisture contamination, cavities which had not been prepared with a bur, increasing patient age, cavities in dentine only and non-carious cavities. Greater durability of these frequently placed restorations can be achieved principally by improving operator skill, followed by cavity preparation and appropriate material handling.
Kaplan-Meier plot of time to restoration failure for different restoration materials in carious Class V cavities. Non-carious cervical lesions. J Dent ; 22 : — Article Google Scholar. Perez C R. Oper Dent ; 35 : — Fundamentals of operative dentistry: a contemporary approach. Chicago: Quintessence Publishing Co Inc. Google Scholar. Noncarious cervical lesions NCCL -a clinical concept based on the literature review. Part 2: restoration.
Am J Dent ; 24 : — PubMed Google Scholar. Bartlett D W, Shah P. A critical review of non-carious cervical wear lesions and the role of abfraction, erosion, and abrasion.
J Dent Res ; 85 : — Noncarious cervical lesions and abfractions: a re-evaluation. J Am Dent Assoc ; : — Relationship between bond-strength tests and clinical outcomes. Dent Mater ; 26 : e— Heintze S D. Systematic reviews: I. The correlation between laboratory tests on marginal quality and bond strength. The correlation between marginal quality and clinical outcome. J Adhes Dent ; 9 Suppl 1 : 77— Clinical evaluation of a self-etch adhesive in non-carious cervical lesions.
Am J Dent ; 21 : — A randomized controlled clinical trial of a HEMA-free all-in-one adhesive in non-carious cervical lesions at 1 year. J Dent ; 36 : — Onal B, Pamir T. The two-year clinical performance of esthetic restorative materials in noncarious cervical lesions. Noncarious Class V lesions restored with a polyacid modified resin composite and a nanocomposite: a two-year clinical trial.
J Adhes Dent ; 10 : — Revised American Dental Association acceptance program guidelines for dentin and enamel adhesive materials. Chicago: American Dental Association, Steele J. London: Department of Health, Clinical success of Class V composite resin restorations without mechanical retention. Long-term dentin retention of etch-and-rinse and self-etch adhesives and a resin-modified glass ionomer cement in non-carious cervical lesions.
Dent Mater ; 24 : — Clinical performance of a resin-modified glass-ionomer and a compomer in restoring non-carious cervical lesions. Am J Dent ; 14 : — They also exhibit much higher polymerization shrinkage. Although manufacturers promote widespread use of these products, they seem to be more appropriate for use in some small Class I restorations, as pit-and-fissure sealants, as marginal repair materials, or, more infrequently, as the first increment placed as a stress-breaking liner under posterior composites.
Additionally, flowable composites are being used as first small increments in the proximal box of a Class II restoration in an effort to improve marginal adaptation. This approach is somewhat controversial but may be indicated in conjunction with the use of thicker, packable composites, where optimal marginal adaptation is more difficult to achieve. Some manufacturers also are currently marketing flowable composites as bulk-fill materials, to be used to restore most, if not all, of a tooth preparation in posterior teeth.
The manufacturers claim reduced polymerization shrinkage stress, which may occur because of the low elastic modulus of the flowable materials. However, the physical properties of flowable composites are generally poor, and the long-term performance of such restorations is not yet proven. Whether or not flowable composites are used for bulk-filling, they should never be placed in areas of high proximal or occlusal stress because of their comparatively poor wear resistance. More heavily filled composites are far superior for restorations involving occlusal or proximal contact areas.
Glass ionomers have the same favorable characteristics of silicate cements—they release fluoride into the surrounding tooth structure, yielding a potential anti-cariogenic effect, and possess a favorable coefficient of thermal expansion. Although conventional glass ionomers are relatively technique-sensitive with regard to mixing and insertion procedures, they may be good materials for restoration of teeth with root-surface caries because of their inherent potential anti-cariogenic quality and adhesion to dentin.
Similarly, because of the potential for sustained fluoride release, glass ionomers may be indicated for other restorations in patients exhibiting high caries activity. Glass ionomer cements also have been widely advocated for permanent cementation of crowns. Today, most glass ionomers also are available in encapsulated forms that are mixed by trituration.
The capsule containing the mixed material subsequently is placed in an injection syringe for easy insertion into the tooth preparation. In an effort to improve the physical properties and esthetic qualities of conventional glass ionomer cements, resin-modified glass ionomer RMGI materials have been developed Table RMGIs are probably best described as glass ionomers to which resin has been added. An acid-base setting reaction, similar to that of conventional glass ionomer cements, is present.
This is the primary feature that distinguishes these materials from compomers see the next section. Additionally, the resin component affords the potential for light-curing, autocuring, or both. RMGIs are easier to use and possess better strength, wear resistance, and esthetics than do conventional glass ionomers.
Their physical properties are generally inferior to those of composites, however, and their indications for clinical use are limited. Because they have the potential advantage of sustained fluoride release, they may be best indicated for Class V restorations in adults who are at high risk for caries and for Class I and II restorations in primary teeth that would not require long-term service.
Compomers probably are best described as composites to which some glass ionomer components have been added. Primarily light-cured, they are easy to use and gained popularity because of their superb handling properties.
Overall, their physical properties are superior to traditional glass ionomers and RMGIs, but inferior to those of composites. Their indications for clinical use are limited. Although compomers are capable of releasing fluoride, the release is not sustained at a constant rate, and anti-cariogenicity is questionable. The various properties of composites should be understood for achieving a successful composite restoration.
These properties generally require that specific techniques be incorporated into the restorative procedure, either in tooth preparation or in the application of the material.
The various property factors are presented here, with additional information provided primarily in online Chapter 18 but also in Chapters 9 through The LCTE is the rate of dimensional change of a material per unit change in temperature. The closer the LCTE of the material is to the LCTE of enamel, the lower the chance for creating voids or openings at the junction of the material and the tooth when temperature changes occur. The LCTE of modern composites is approximately three times that of tooth structure.
Water sorption is the amount of water that a material absorbs over time per unit of surface area or volume. When a restorative material absorbs water, its properties change, and its effectiveness is usually diminished. All of the available tooth-colored materials exhibit some water absorption.
Materials with higher filler contents exhibit lower water absorption values than materials with lower filler content. Of the remaining restorations, an additional The mean follow-up time was 3.
Replacement rates for resin-based composite restorations compared with amalgam were significantly higher owing to all causes adjusted hazard ratio [HR], 1. Global burden of oral conditions in a systematic analysis.
J Dent Res. Global economic impact of dental diseases. Amalgam or composite resin? Factors influencing the choice of restorative material.
J Dent. Do clinical experience time and postgraduate training influence the choice of materials for posterior restorations? Results of a survey with Brazilian general dentists. Braz Dent J. The esthetic characteristics of matching the natural tooth colour, ability to be bonded to tooth tissues, reduced need of sound tooth removal, and the low cost compared to indirect materials are some of the reasons for the great popularity of composite resins.
Longevity of posterior composite restorations: not only a matter of materials. Dent Mater. Over the years, several studies have evaluated the clinical longevity of posterior and anterior composite restorations. Anterior composite restorations: a systematic review on long-term survival and reasons for failure.
Heintze SD, Rousson V. Clinical effectiveness of direct class II restorations: a meta-analysis. J Adhes Dent. Buonocore Memorial Lecture. Review of the clinical survival of direct and indirect restorations in posterior teeth of the permanent dentition. Oper Dent. Longevity of posterior composite restorations: a systematic review and meta-analysis.
However, replacement of restorations is still very frequent in public and private practices, consuming a significant amount of clinical time and imposing high financial costs for health systems. Dissimination NCfRa. Dental restoration: what type of filling? Eff Health Care. Clinical studies evaluating the longevity of restorations usually aim to determine the risk factors and reasons for failures of restorations.
In addition, the decision-making process on how to deal with a restoration with large or small defects can vary widely among dentists with different training status or background. The decision after clinically assessing an old restoration can vary from doing nothing, repairing or replacing.
The decision-making process is probably the most determinant factor for the longevity of restorations. In the past, most studies would concentrate on the clinical performance of different composite materials.
Since the current restorative composites seem not to be the problem anymore 5 5. These may include factors related to the patient age, caries and occlusal stress risk, socioeconomic status and the professional age, gender, clinical experience. The present manuscript aims to present an overview of the recent literature regarding the clinical performance of direct composite restorations in anterior and posterior teeth and discuss the main factors affecting longevity. In the last five years, systematic reviews have focused on the longevity of composite restorations, assessing AFRs or survival rates.
The results of these recent studies were summarized in Table. Although many times neglected in restorative survival analysis, patient-related factors play an important role on the longevity of restorations. Studies have indicated the inclusion of patient factors in the analysis in order to assist with the process of basing clinical decision making on outcomes that are more predictable, and also for patient awareness. Establishing the effect of patients and their related variables is not easy in clinical studies.
While age, decayed, missing, and filled teeth index, and socioeconomic status are straightforward variables that can be easily collected, caries risk and parafunctional habits, for instance, are complex processes involving several signs and symptoms, increasing the challenge of choosing the best collection method and criteria to be applied. Since each patient related factors hold its own particularities, the following discussion is presented in topics. Caries risk of patients has been shown to significantly influence the longevity of restorations.
Studies have been demonstrated that for individuals classified as having high caries risk, the hazard ratio for failure of posterior composite restorations ranged from 2. A retrospective clinical study on longevity of posterior composite and amalgam restorations. An increased risk of restoration failure was also observed in direct posterior restorations placed in children which have presented a high DMFT index 22 Pediatr Dent. Among studies on survival of anterior restorations, none have investigated this influence, probably motivated by a low incidence of caries found in this region.
A recent systematic review on survival of anterior composite restoration have shown a low number of failed restoration due to secondary caries. However, patients with caries in anterior teeth are typically high-risk patients, thus we can expect on this kind of patient an increased risk for failure of restorations.
Although studies have tried to confirm this evidence, there is still a lack of standardization on the establishment of caries risk profile. Due to multifactorial characteristics of caries disease, several risk indicators variables should be collected for a correct identification of graded risk status and future caries prediction, guiding preventive and treatment strategies at the individual level. However, on the investigation of restoration longevity, the use of simplified measures may provide a good estimate of the disease activity when the restoration is placed and in follow-up evaluations.
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