后牙复合树脂充填的临床评价

临床经验显示,后牙树脂充填还存在着很大的临床挑战,如后牙树脂充填后可能发生继发龋、充填体折裂、术后疼痛、边缘着色以及充填体着色等。本文综述了目前有关后牙复合树脂充填在临床上所遇到的问题,期望得出更加客观和科学的结论,从而为提高后牙复合树脂充填的临床效果提供一些参考。     

Reducing marginal leakage of posterior composite resin restorations: a review of clinical techniques

It has been well established that composite resin restorations have leakage at the margins. The polymerization shrinkage of the material and its inadequate adhesion to the cavity walls are the primary causes. Unlike silver amalgam restorations, which are self-sealing with age, the gap at the composite-to-tooth interface tends to persist and invite postoperative sensitivity, adverse pulp reactions, and the development of recurrent caries. Many techniques or materials have been advocated to improve the clinical adaptation of this material and to reduce marginal leakage. They limit the effect of polymerization shrinkage and/or enhance the bonding of the composite material to the tooth structure. This article reviews the clinical techniques and materials that have been suggested and are presently available to improve the marginal quality of composite resins, with special reference to posterior restorations.     

A rational use of dental materials in posterior direct resin restorations in order to control polymerization shrinkage stress

One of the main problems when using resin-based composites is the resulting polymerization shrinkage stress. Composite strain is hindered every time the composite is bonded to the tooth's walls. In the pre-gel phase the shrinkage stress is reduced by the composite flow from the free to the bonded surface areas. Therefore, no stress develops at the dentine-composite interface. When a gel point is reached, the composite flow no longer compensates for the volumetric shrinkage. The generated stress may cause adhesive failure and several other adverse clinical consequences such as enamel fracture, cracked cusps, cuspal movement, microcracking of the restorative material and gaps between the resin and cavity walls which may cause secondary caries and postoperative sensitivity. A sensible use of materials in direct restorations may contribute to a reduced rate of shrinkage stress. To this aim glass-ionomer cement as well as flowable, light-curing and self-curing composites were examined. The aim of this study was to provide some useful information for a sensible choice of restoration materials in order to control shrinkage stress and its negative consequences in direct posterior restorations.     

An alternative method to reduce polymerization shrinkage in direct posterior composite restorations

BACKGROUND: Polymerization shrinkage is one of dental clinicians' main concerns when placing direct, posterior, resin-based composite restorations. Evolving improvements associated with resin-based composite materials, dental adhesives, filling techniques and light curing have improved their predictability, but shrinkage problems remain. METHODS: The authors propose restoring enamel and dentin as two different substrates and describe new techniques for placing direct, posterior, resin-based composite restorations. These techniques use flowable and microhybrid resin-based composites that are polymerized with a progressive curing technique to restore dentin, as well as a microhybrid composite polymerized with a pulse-curing technique to restore enamel. Combined with an oblique, successive cusp buildup method, these techniques can minimize polymerization shrinkage greatly. CONCLUSIONS: Selection and appropriate use of materials, better placement techniques and control polymerization shrinkage may result in more predictable and esthetic Class II resin-based composite restorations. CLINICAL IMPLICATIONS: By using the techniques discussed by the authors, clinicians can reduce enamel microcracks and substantially improve the adaptation of resin-based composite to deep dentin. As a consequence, marginal discoloration, recurrent caries and postoperative sensitivity can be reduced, and longevity of these restorations potentially can be improved.     

A review of polymerization shrinkage stress: current techniques for posterior direct resin restorations

In general excellent results cannot be guaranteed when using resin-based composites for posterior restorations. This is due to polymerization shrinkage which can still be regarded as the primary negative characteristic of composite resins. A review of available literature regarding the polymerization process, its flaws, and suggested strategies to avoid shrinkage stress was conducted. Several factors responsible for the polymerization process may negatively affect the integrity of the tooth-restoration complex. There is no straightforward way of handling adhesive restorative materials that can guarantee the reliability of a restoration. At present, the practitioner has to coexist with the problem of polymerization shrinkage and destructive shrinkage stress. However, evolving improvements associated with resin-based composite materials, dental adhesives, filling, and light curing techniques have improved the predictability of such restorations. This critical review paper is meant to be a useful contribution to the recognition and understanding of problems related to polymerization shrinkage and to provide clinicians with the opportunity to improve the quality of composite resin restorations.     

Prediction of clinical outcomes of a restoration based on in vivo marginal quality evaluation

The question "Does initial marginal quality of composite restorations have any affect on clinical longevity?" is posed and evidence presented to attempt to provide an answer. This paper examines the literature on what is known regarding the rates and causes of failure of restorations, clinical evaluation of restoration outcomes and marginal quality, the relationship between marginal quality and secondary caries, and the relationship of polymerization shrinkage and clinical failures. The most frequently reported cause for restoration replacement is secondary caries. The evidence that poor marginal quality promotes or is the primary cause for secondary caries is limited and indicates that any direct relationship is unlikely. There is evidence that secondary caries is related to the bacterial composition of marginal plaque, and that this and oral hygiene are the primary factors in disease initiation. Evidence also exists that dentists vary in their diagnoses of secondary caries and that except in the presence of frank secondary caries, it is not possible to diagnose secondary caries with high sensitivity and specificity based on visual and tactile examination of restoration margins. Marginal gaps created by polymerization shrinkage do not appear to increase the risk for secondary caries, but can lead to marginal staining. Initial marginal quality should not affect longevity, as it does not necessarily increase the risk of secondary caries. However, poor marginal quality is, in fact, likely to decrease clinical longevity due to the misdiagnosis of secondary caries.     

Developments in Shrinkage Control of Adhesive Restoratives

Purpose: This article reviews material properties and application techniques important in minimizing effects of polymerization shrinkage during the curing reaction of resin composite restorative materials used in adhesive dentistry.
Materials and Methods: Relevant scientific publications were critically reviewed.
Results: Since it was recognized that shrinkage, which takes place during the curing reaction of resin composite restorative materials, may cause severe problems in adhesive dentistry, considerable effort has been put into reducing the negative effects. The most important problem is the debonding of the restoration-tooth interface, resulting in increased microleakage and, ultimately, in secondary caries. Despite all efforts, there is still no material or general application method that guarantees a leak-proof and durable restoration.
CLINICAL SIGNIFICANCE
It is of the utmost importance that dental practitioners know how to deal with the problems related to resin composite shrinkage, so that they can choose the material and procedure most likely to produce a leak-proof and durable restoration, maximizing the potential for clinical success.     

Developments in shrinkage control of adhesive restoratives

PURPOSE: This article reviews material properties and application techniques important in minimizing effects of polymerization shrinkage during the curing reaction of resin composite restorative materials used in adhesive dentistry. MATERIALS AND METHODS: Relevant scientific publications were critically reviewed. RESULTS: Since it was recognized that shrinkage, which takes place during the curing reaction of resin composite restorative materials, may cause severe problems in adhesive dentistry, considerable effort has been put into reducing the negative effects. The most important problem is the debonding of the restoration-tooth interface, resulting in increased microleakage and, ultimately, in secondary caries. Despite all efforts, there is still no material or general application method that guarantees a leak-proof and durable restoration. CLINICAL SIGNIFICANCE: It is of the utmost importance that dental practitioners know how to deal with the problems related to resin composite shrinkage, so that they can choose the material and procedure most likely to produce a leak-proof and durable restoration, maximizing the potential for clinical success.     

A new approach to restorative dentistry: fabricating ceramic restorations using CEREC CAD/CAM

Ceramic materials provide an alternative when choosing a tooth-colored restoration. Currently, posterior composite restorations can be used to achieve esthetic restorations; however, they have many disadvantages with regard to wear, polymerization shrinkage, discoloration, marginal leakage, and technique sensitivity. The use of CEREC CAD/CAM enables the dentist to place feldspathic porcelain (Vitablocs Mark II) and machinable glass ceramic (Dicor MGC) restorations in a single visit. When compared to composite materials, these materials closely approximate the physical properties of enamel in compressive and tensile strength and wear resistance. This study evaluated 50 CEREC CAD/CAM restorations after 4 years in service. Restorations ranged from Class I to 7/8s crown preparations.     

Clinical evaluation of different posterior resin composite materials: a 7-year report.

OBJECTIVES: The aim of this study was to investigate the clinical performance of 120 posterior composite restorations placed in 38 patients after a period of 7 years. METHOD AND MATERIALS: Eighty-eight Class I and 32 Class II restorations were made (93 molars and 27 premolars) using three different resin composite materials: Z100, Clearfil Ray-Posterior, and Prisma TPH. The restorations were evaluated using Ryge's criteria for color match, marginal discoloration, marginal adaptation, secondary caries, surface texture, and anatomic form at baseline, 1,2, 5, and 7 years. Photographs and radiographs were taken at each recall period. RESULTS: At 7-year recalls, 70 restorations were available for examination. Four restorations had failed due to secondary caries. Saliva sampling was performed to determine the level of mutans streptococci and lactobacilli for the four failed restorations at the last recall. No statistically significant differences were found among the materials in regard to color match, anatomic form, and secondary caries. Clearfil Ray-Posterior had statistically significantly rougher surface texture than the surrounding enamel compared to the other resin composites. Z100 showed more cavosurface margin discoloration after 5 years than the other two resin composites. All materials had slight marginal adaptation problems at the 7-year recall. There was no apparent relationship between the levels of mutans streptococci and lactobacilli in saliva and the failed restorations. CONCLUSION: The three posterior composites tested had acceptable clinical performance after 7 years.     

Dental materials for posterior restorations

Abstract Assessment of the quality of dental restorations by the Ryge system is described. Generally, the quality of dental restorations is shown to be dependent on the technique sensitivity of the restorative material as well as the skill and experience of the dentist. Concerning biocompatibility, adverse reactions related to amalgam restorations are unlikely or scarce, due to small amounts of released mercury. Resin based restorative materials contain a large number of organic compounds and, as such, the toxic and allergenic potentials are unknown. Gold and ceramics turn out to be the most biotolerable dental materials. Based on studies on longevity, data indicate that the median age of amalgam restorations is 10-12 years, of gold castings 13-14 years and more, and of composite restorations 4 years. Data on longevity of ceramic restorations are sparse. Secondary caries appears to be the most frequent cause for replacement of the different restorations, followed by marginal degradation. Secondary caries account for more failures among the resin based restorations than among amalgam. Reviewing the literature, it appears that amalgam is the best and most economic dental material for routine posterior restorations with reasonable durability. Gold is recommended for complex restorations. Resin based composites may be limited to small restorations where cosmetics is the main aspect, as wear and recurrent caries are main problems. Ceramic restorations comprise aesthetic restorations with excellent bio-compatibility, however, data on longevity and marginal adaptation are not encouraging.     

Dental materials for posterior restorations.

Assessment of the quality of dental restorations by the Ryge system is described. Generally, the quality of dental restorations is shown to be dependent on the technique sensitivity of the restorative material as well as the skill and experience of the dentist. Concerning biocompatibility, adverse reactions related to amalgam restorations are unlikely or scarce, due to small amounts of released mercury. Resin based restorative materials contain a large number of organic compounds and, as such, the toxic and allergenic potentials are unknown. Gold and ceramics turn out to be the most biotolerable dental materials. Based on studies on longevity, data indicate that the median age of amalgam restorations is 10-12 years, of gold castings 13-14 years and more, and of composite restorations 4 years. Data on longevity of ceramic restorations are sparse. Secondary caries appears to be the most frequent cause for replacement of the different restorations, followed by marginal degradation. Secondary caries account for more failures among the resin based restorations than among amalgam. Reviewing the literature, it appears that amalgam is the best and most economic dental material for routine posterior restorations with reasonable durability. Gold is recommended for complex restorations. Resin based composites may be limited to small restorations where cosmetics is the main aspect, as wear and recurrent caries are main problems. Ceramic restorations comprise aesthetic restorations with excellent biocompatibility, however, data on longevity and marginal adaptation are not encouraging.     

Longevity of posterior composite restorations: Not only a matter of materials

Resin composites have become the first choice for direct posterior restorations and are increasingly popular among clinicians and patients. Meanwhile, a number of clinical reports in the literature have discussed the durability of these restorations over long periods. In this review, we have searched the dental literature looking for clinical trials investigating posterior composite restorations over periods of at least 5 years of follow-up published between 1996 and 2011. The search resulted in 34 selected studies. 90% of the clinical studies indicated that annual failure rates between 1% and 3% can be achieved with Class I and II posterior composite restorations depending on several factors such as tooth type and location, operator, and socioeconomic, demographic, and behavioral elements. The material properties showed a minor effect on longevity. The main reasons for failure in the long term are secondary caries, related to the individual caries risk, and fracture, related to the presence of a lining or the strength of the material used as well as patient factors such as bruxism. Repair is a viable alternative to replacement, and it can increase significantly the lifetime of restorations. As observed in the literature reviewed, a long survival rate for posterior composite restorations can be expected provided that patient, operator and materials factors are taken into account when the restorations are performed.     

Direct posterior restorations: clinical results and new developments

The longevity of dental restorations is dependent on many different factors, including those related to materials, the dentist, and the patient. The main reasons for restoration failure are secondary caries, fracture of the bulk of the restoration or of the tooth, and marginal deficiencies and wear. The importance of direct-placement, aesthetic, tooth-colored restorative materials is still increasing. Amalgam restorations are being replaced because of alleged adverse health effects and inferior aesthetic appearance. All alternative restorative materials and procedures, however, have certain limitations. Direct composite restorations require a time-consuming and more costly treatment procedure and are actually only indicated for patients with excellent oral hygiene. Glass ionomers can be considered only as long-term provisional restorations in stress-bearing posterior cavities. Future treatment regimens that are made possible by the development of sophisticated preparation techniques, improved dentin bonding agents, and resin-based restorative materials will result in the therapy of more small-sized lesions rather than large restorations. The importance of indirect inlay techniques will shift more and more toward the direct restoratives. As the cavities become smaller, it is to be expected that the use of improved direct restorative materials will provide excellent longevity even in stress-bearing situations.     

Survival and reasons for failure of amalgam versus composite posterior restorations placed in a randomized clinical trial

BACKGROUND: Failure of dental restorations is a major concern in dental practice. Replacement of failed restorations constitutes the majority of operative work. Clinicians should be aware of the longevity of, and likely reasons for the failure of, direct posterior restorations. In a long-term, randomized clinical trial, the authors compared the longevity of amalgam and composite. SUBJECTS, METHODS AND MATERIALS: The authors randomly assigned one-half of the 472 subjects, whose age ranged from 8 through 12 years, to receive amalgam restorations in posterior teeth and the other one-half to receive resin-based composite restorations. Study dentists saw subjects annually to conduct follow-up oral examinations and take bitewing radiographs. Restorations needing replacement were failures. The dentists recorded differential reasons for restoration failure. RESULTS: Subjects received a total of 1,748 restorations at baseline, which the authors followed for up to seven years. Overall, 10.1 percent of the baseline restorations failed. The survival rate of the amalgam restorations was 94.4 percent; that of composite restorations was 85.5 percent. Annual failure rates ranged from 0.16 to 2.83 percent for amalgam restorations and from 0.94 to 9.43 percent for composite restorations. Secondary caries was the main reason for failure in both materials. Risk of secondary caries was 3.5 times greater in the composite group. CONCLUSION: Amalgam restorations performed better than did composite restorations. The difference in performance was accentuated in large restorations and in those with more than three surfaces involved. CLINICAL IMPLICATIONS: Use of amalgam appears to be preferable to use of composites in multisurface restorations of large posterior teeth if longevity is the primary criterion in material selection.     

One-year clinical evaluation of composite fillings and inlays in posterior teeth

In the course of a prospectively designed long-term clinical trial, composite fillings and inlays were evaluated for clinical acceptability as restorative materials in one, two or more surface cavities of posterior teeth over a 1-year period. In 45 patients, 88 restorations were placed by nine student operators, under the supervision of an experienced dentist, to compare the two half sides using the composite resins Tetric (Vivadent), blend-a-lux (Blend-a-med), and Pertac-Hybrid Unifil (Espe). The first clini-cal follow-up check took place within a time period of 11 – 13 months after placement of the restorations using modified USPHS criteria. The interpretation of the clinical criteria showed satisfactory results over this time period: more than 85% of the inlays and direct fillings were rated ``alpha' or ``bravo', using the parameters of assessment defined in this study. Only three restorations (two fillings, one inlay), all in molars, were rated ``delta', i. e., unacceptable. The reasons for their replacement were mar-ginal opening, secondary caries, and loss of sensitivity. For the criteria ``surface texture', ``anatomical form of the surface', and ``occlusion', composite inlays were significantly better than composite fillings. These results indicate that posterior composite restorations provide acceptable and excellent clinical service, even if they are placed by relatively inexperienced student operators.     

Repair of dimethacrylate-based composite restorations by a silorane-based composite: a one-year randomized clinical trial

SUMMARY Purpose : To investigate clinical performance of a low-shrinkage silorane-based composite resin when used for repairing conventional dimethacrylate-based composite restorations. Background : Despite the continued development of resin-based materials, polymerization shrinkage and shrinkage stress still require improvement. A silorane-based monomer system was recently made available for dental restorations. This report refers to the use of this material for making repairs and evaluates the clinical performance of this alternative treatment. Materials and Methods : One operator repaired the defective dimethacrylate-based composite resin restorations that were randomly assigned to one of two treatment groups: control (n=50) repair with Adper SE Plus (3M/ESPE) and Filtek P60 Posterior Restorative (3M/ESPE), and test (n=50) repair with P90 System Adhesive Self-Etch Primer and Bond (3M/ESPE) and Filtek P90 Low Shrink Posterior Restorative (3M/ESPE). After one week, restorations were finished and polished. Two calibrated examiners (Kw≥0.78) evaluated all repaired restorations, blindly and independently, at baseline and one year. The parameters examined were marginal adaptation, anatomic form, surface roughness, marginal discoloration, postoperative sensitivity, and secondary caries. The restorations were classified as Alpha, Bravo, or Charlie, according to modified US Public Health Service criteria. Mann-Whitney and Wilcoxon tests were used to compare the groups. Results : Of the 100 restorations repaired in this study, 93 were reexamined at baseline. Dropout from baseline to one-year recall was 11%. No statistically significant differences were found between the materials for all clinical criteria, at baseline or at one-year recall (p>0.05). No statistically significant differences were registered (p>0.05) for each material when compared for all clinical criteria at baseline and at one-year recall. Conclusions : The hypothesis tested in this randomized controlled clinical trial was accepted. After the one-year evaluations, the silorane-based composite exhibited a similar performance compared with dimethacrylate-based composite when used to make repairs.     

Comparison between published clinical success of direct resin composite restorations in vital posterior teeth in 1995–2005 and 2006–2016 periods

Composites are increasing in popularity as restorative materials. This growing role indicates the necessity of studies on their clinical outcome. In this study, clinical studies published on the performance of posterior composite restorations were included except those of less than a 24‐month assessment period. Results of non‐vital, anterior or primary teeth and cervical single‐surface restorations were also excluded. Records about composite type, number of final recall restorations, failure/survival rate, assessment period and failure reasons were analysed for each decade. Overall survival/failure rates for studies in 1995–2005 were 89.41%/10.59% and for 2006–2016 were 86.87%/13.13%, respectively. In 1995–2005, the reasons for failure were secondary caries (29.47%) and composite fracture (28.84%) with low tooth fracture (3.45%) compared with reasons of failure in 2006–2016, which were secondary caries (25.68%), composite fracture (39.07%), and tooth fracture (23.76%). An increase in incidence of composite fracture, tooth fracture and need for endodontic treatment as failure reasons was noted in the latter decade in addition to a decrease in secondary caries, postoperative sensitivity, unsatisfactory marginal adaptation and wear. The overall rates of failure showed little difference, but the causes showed a notable change. This is believed to be a reflection of increased use of composites for larger restorations and possibly changes of material characteristics.     

Posterior composite resin inlays and onlays: a comparison of available systems

With the increasing proliferation of materials and techniques for placement of posterior composite resin restorations, the dentist must have the information to make informed judgements on which to use in various clinical situations. This paper examines the advantages and disadvantages of each of three systems: 1) Direct, 2) Direct/Indirect and 3) Indirect. The increased demand for posterior esthetic restorations has been one of the hallmarks of the eighties. According to a recent American Dental Association survey, the use of resin restorations in posterior teeth is markedly increasing and is the restoration of choice over amalgam for 70 percent of those dentists who responded to the survey. For the restorative dentist who chooses to do posterior esthetic restorations, the biggest challenge lies in acquiring the knowledge and judgement to know which of the three current classes of materials and techniques to apply to each clinical situation. Although the influx of new materials into the marketplace makes it difficult to evaluate and categorize these materials as accurately as would be desired, generally, posterior composite resins can be classified in three general categories based on method of placement. These categories are: a) Direct placement b) Direct/Indirect placement or Direct Composite Inlay (DCI) c) Indirect placement     

Long term clinical performance of ‘open sandwich’ and ‘total-etch’ Class II composite resin restorations showing proximal deterioration of glass-ionomer cement

ObjectivesTo compare clinical performance of resin composite posterior Class-II restorations placed with etch-and-rinse adhesive or open sandwich technique using glass-ionomer cement.MethodsData on Class II restorations placed by one dentist between 1990 and 2016 were collected from patient files, including caries risk, tooth related variables, applied materials and dates of last check-up visit and restoration placement.Open sandwich restorations were placed before 2001, while after 2001, a total-etch technique using etch-and-rinse 3-step adhesive was used when placing a Class II composite restoration. For statistical analysis, Kaplan-Meier statistics and a multilevel Cox-Regression was conducted (p < 0.05). Annual Failures Rates (AFR) were calculated.Results675 Class II restorations were placed in 91 patients, 491 total-etch restorations (observation time 2–18 y), and 184 open sandwich restorations (observation time 19–29 y) showing AFRs at 15 years as 2.9 % for total-etch and 9.7 % for open sandwich restorations.Secondary caries as failure was equally distributed among the 2 groups and 27 % of the failures in the open sandwich group were due to proximal deterioration of glass-ionomer cement. The Cox-regression showed a significant higher risk for failure for the open sandwich technique compared to total-etch class-II composite restorations (HR = 2.9; p < 0.001).SignificanceApplication of glass-ionomer cement using the open sandwich technique cannot be recommended for class-II restorations as being more complex and showing poorer clinical performance.