Five-year clinical performance of posterior resin composite restorations placed by dental students

OBJECTIVES: To investigate the survival over a five-year period of posterior resin composite restorations placed by students. METHODS: Class I and II resin composite restorations placed by second-fourth year dental students were evaluated. Patients attended the dental school every 6 months for a regular check-up during which all restorations were checked on their clinical acceptability. In case of replacement or repair of a restoration, this was registered in the patient's record. From each record the survival time and reasons for failure of resin composite restorations were gathered. RESULTS: Seven-hundred three posterior resin composite restorations in 382 patients (49% female and 51% male, age 22-78) were evaluated. At 5 years 560 of the 703 restorations were still considered to be "clinically acceptable". Forty-nine restorations were considered as "functionally present", of which 44 were restored with a crown and four had received a new restoration adjacent to the existing restoration without its removal. Ninety-four restorations had failed. The main reasons for failure were restoration fracture, caries, endodontic treatment, defective margin and lack of proximal contact. The survival rate of the restorations was 87% at 5 years, resulting in an annual failure rate of 2.8%. CONCLUSIONS: Dental students are able to place resin composite restorations in posterior teeth with an acceptable mean annual failure rate.     

Survey on the teaching and use in dental schools of resin-based materials for restoring posterior teeth

A survey was conducted of 100 dental schools worldwide to investigate the current teaching of posterior resin composite restorations. A 20 multi-part question questionnaire was emailed to the selected schools. Schools were selected by ability to understand and respond in English. The questionnaire consisted of four open-ended questions and 16 closed questions on topics such as material selection for restoring posterior teeth, preclinical teaching of resin composite for posterior teeth, restoration size, contraindications, matrix placement methods, lining use, adhesive selection and finishing. Forty-six schools responded. The outcomes showed all schools included the teaching of resin composite for posterior restorations but varied. The majority of schools (63%) no longer taught amalgam as the preferred posterior restorative material. Half of the schools surveyed set numerical clinical requirements for restoration placement. Australian schools had no requirements whilst 92% of Asian schools did. There was a consensus that larger restorations were less suitable for resin composite. Selection of adhesives depended on region. Generally, the schools surveyed showed minor variations philosophically in teaching of the use and placement of resin composite restorations.     

Longevity of posterior resin composite restorations in permanent teeth in Public Dental Health Service: A prospective 8 years follow up

ObjectivesTo investigate in a prospective follow up the longevity of posterior resin composites (RC) placed in permanent teeth of children and adolescents attending Public Dental Health Service.MethodsAll posterior RC placed, in the PDHS clinics in the cities of Copenhagen and Frederiksberg in Denmark between November 1998 and December 2002, in permanent teeth of children and adolescents up to 18 years, were evaluated in an up to 8 years follow up. The endpoint of each restoration was defined, when repair or replacement was performed. Survival analyses were performed between subgroups with Kaplan–Meier analysis. The individual contribution of different cofactors to predict the outcome was performed with Cox regression analysis.ResultsTotally 2881 children with a mean age of 13.7 years (5–18) received 4355 RC restorations placed by 115 dentists. Eighty percent were placed in molars and 49% were Class I. Two percent of restorations with base material and 1% of the restorations without base material showed postoperative sensitivity (n.s.). Replacements were made in 406 and repairs in 125 restorations. Kaplan–Meier analysis showed a cumulative survival at 8 years of 84.3%, resulting in an annual failure rate of 2%. Lower patient age, more than one restoration per patient, placement of a base material and placement of RC: in molars, in cavities with high number of surfaces, in lower jaw teeth, showed all significant higher failure rates. Five variables had significant importance for the end point, replacement/repair of the resin composite restorations: age of patient, age of operator, jaw, tooth type and cavity size.SignificancePosterior RC restorations placed in children and adolescents in Public Dental Health clinics showed an acceptable durability with annual failure rates comparable with those of randomized controlled RC studies in adults.     

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     

In vitro dentin demineralization inhibition effects of an experimental fluoridated HEMA and water wetting agent

The ability of fluoride-releasing resins to inhibit dentin demineralization remains controversial. The purpose of this study was to evaluate the caries inhibition of resin composite restorations with an experimental fluoridated hydroxyethyl methyl methacrylate (HEMA) and water wetting agent. Standardized Class V preparations were placed in 40 molars, the gingival margin placed below the cementoenamel junction. Two dentin primers (sodium fluoride, HEMA and water; HEMA and water) were placed in equal numbers of 20 preparations, then One-Step Dental Adhesive (Bisco) was applied as recommended by the manufacturer, followed by the placement of a resin composite restoration. Amalgam restorations with no primer/adhesive were placed in 10 preparations and 10 preparations were restored by placing One-Step Dental Adhesive, then resin composite. All teeth were subjected to an artificial caries challenge (pH 4.4) for 5 days. Results demonstrated the mean areas (microm2 +/- s.d.) of demineralization 100 microm from the restoration/dentin margin to be: amalgam 5,570 +/- 873; One-Step 7,038 +/- 2,099; HEMA and water 6,126 +/- 634; fluoridated HEMA and water 3,411 +/-593. ANOVA and Duncan's test (P < 0.05) demonstrated the fluoridated HEMA and water wetting agent to have significantly less adjacent dentin demineralization than the other three groups. Eighty percent of HEMA and water wetting agent, 80% of One-Step Dental Adhesive and 100% of amalgam restorations demonstrated wall lesions. One hundred percent of restorations with fluoridated HEMA and water wetting agent demonstrated inhibition zones in adjacent dentin.     

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.     

The future of dental amalgam

This paper is a comment on 'The enigma of dental amalgam' by Carl Leinfelder published in 2004 in the Journal of Esthetic and Restorative Dentistry. In that paper a warning is stated against a too abrupt change from amalgam towards resin composite, because this will bring a lot of clinical problems due to the limited skills of todays' dentists in placing posterior composite resin restorations. However, the situation in The Netherlands is different since a gradual changeover from amalgam towards resin composites has taken place during the last decades and dental schools have skipped training in placing amalgam restorations out of the curriculum. Clinical studies on the longevity of amalgam and resin composite restorations placed by dental students and dentists who are experienced in both composite resin and amalgam placement show a comparable and acceptable annual failure rate for those restorations. It is concluded that a gradual changeover from amalgam towards composite resin is preferred to avoid clinical problems.     

A 3-year follow-up study of preformed beta-quartz glass-ceramic insert restorations.

OBJECTIVE: The purpose of this study was to evaluate the clinical performance of preformed beta-quartz glass-ceramic insert restorations. METHODS AND MATERIALS: Nine Class I and 30 Class II beta-quartz glass-ceramic insert restorations were placed in 16 patients who were seen regularly by personnel at Ume? University Dental School. The California Dental Association criteria were used to evaluate the restorations at baseline, 6 months, and 1, 2, and 3 years after luting. The occurrence of postoperative sensitivity, the time taken to manufacture each restoration, and certain periodontal conditions were also evaluated. RESULTS: Sixty-nine percent of the restorations were rated satisfactory at the 3-year examination. During the follow-up period, 4 became loose and 7 were fractured or had flaking surfaces. Caries was registered in connection with 1 restoration. Excellent ratings were obtained for marginal integrity, anatomic form, surface, and color in 62%, 84%, 32%, and 44% of the restorations, respectively. There was no statistically significant difference in the occurrence of plaque and bleeding on probing in comparison with the controls. The mean overall time for placement was 38 minutes. The estimated survival rate (Kaplan-Meier) was 59% after 3.5 years. CONCLUSION: The quality of the beta-quartz glass-ceramic restorations in the present study was inferior to that presented in most earlier studies of ceramic or resin composite posterior restorations placed in patients treated at university clinics. Both the technique and the beta-quartz glass-ceramic inserts have to be evaluated in more long-term studies to assess the possibility of their serving as an alternative restorative technique.     

Repair or replacement of defective direct resin-based composite restorations: contemporary teaching in U.S. and Canadian dental schools

BackgroundOpportunities exist to promote minimally invasive dentistry by repairing rather than replacing defective and failing direct resin-based composite restorations. The authors conducted a study to investigate the current teaching of such techniques in U.S. and Canadian dental schools.MethodsIn late 2010, the authors, with the assistance of the Consortium of Operative Dentistry Educators, invited 67 U.S. and Canadian dental schools to participate in an Internet-based survey.ResultsThe response rate was 72 percent. Eighty-eight percent of the dental schools taught repair of defective direct resin-based composite restorations. Of these schools, 79 percent reported providing both didactic and clinical teaching.ConclusionsAlthough teaching repair of defective resin-based composite restorations was included in the didactic curricula of most schools, students in some schools did not gain experience in minimally invasive management of defective resin-based composite restorations by means of performing repair procedures. The American Dental Association's Code on Dental Procedures and Nomenclature does not have a procedure code for resin-based composite restoration repairs, which may limit patients' access to this dental treatment.Clinical ImplicationsTeaching dental students minimally invasive dentistry procedures, including restoration repair, extends the longevity of dental restorations and reduces detrimental effects on teeth induced by invasive procedures, thereby serving the interests of patients.     

Polymerization contraction stress of resin composite restorations in a model Class I cavity configuration using photoelastic analysis

PURPOSE: An important factor that contributes to deterioration of resin composite restorations is contraction stress that occurs during polymerization. The purpose of this article is to familiarize the clinician with the characteristics of contraction stress by visualizing the stresses associated with this invisible and complex phenomenon. MATERIALS AND METHODS: Internal residual stresses generated during polymerization of resin composite restorations were determined using micro-photoelastic analysis. Butt-joint preparations simulating Class I restorations (2.0 mm x 5.0 mm, 2.0 mm in depth) were prepared in three types of substrates (bovine teeth, posterior composite resin, and transparent composite resin) and were used to examine contraction stress in and around the preparations. Three types of composite materials (a posterior composite, a self-cured transparent composite, and a light-cured transparent composite) were used as the restorative materials. The self-cured composite is an experimental material, and the others are commercial products. After treatment of the preparation walls with a bonding system, the preparations were bulk-filled with composite. Specimens for photoelastic analysis were prepared by cutting sections perpendicular to the long axis of the preparation. Fringe patterns for directions and magnitudes of stresses were obtained using transmitted and reflected polarized light with polarizing microscopes. Then, the photoelastic analysis was performed to examine stresses in and around the preparations. RESULTS: When cavity preparations in bovine teeth were filled with light-cured composite, a gap was formed between the dentinal wall and the composite restorative material, resulting in very low stress within the restoration. When cavity preparations in the posterior composite models were filled with either self-cured or light-cured composite, the stress distribution in the two composites was similar, but the magnitude of the stress was greater in the light-cured material. When preparations in the transparent composite models were filled with posterior composite and light-cured transparent composite material, significant stress was generated in the preparation models simulating tooth structure, owing to the contraction of both restorative materials. CLINICAL SIGNIFICANCE: Polymerization contraction stress is an undesirable and inevitable characteristic of adhesive restorations encountered in clinical dentistry that may compromise restoration success. Clinicians must understand the concept of polymerization contraction stress and realize that the quality of composite resin restorations depends on successful management of these stresses.     

Clinical performance of posterior composite resin restorations.

Two formulations of posterior composite resin (P-30 and Bisfil-P) were evaluated and compared to a high-copper, dispersed-phase amalgam (Dispersalloy). One hundred twenty-eight restorations were placed in 27 patients so that each patient received at least one of each material. After 3 years of clinical service, all three restorative materials produced clinically acceptable restorations, according to US Public Health Service and Leinfelder criteria. The amalgam restorations, however, underwent less wear (44 microns) than did the posterior composite resin restorations (60 to 74 microns). Stratification of data by type of tooth, class of restoration, and size of restoration produced the same ranking of wear from lowest to highest: Dispersalloy, Bisfil-P, and P-30. Resin restorations showed 45% more wear in molars than in premolars, and more wear was associated with moderately sized restorations than with conservative restorations. The surface texture of restorations of composite resin with porous strontium glass filler was nearly as smooth as that of enamel and was significantly smoother than that of the restorations of composite resin with zinc glass filler or of unpolished amalgam.     

Colorimetric Determination of Iron with Orthophenanthroline at High Electrolyte Concentrations

Abstract

Objective. The purpose of the present survey was to evaluate the implementation and experience of a new method for posterior vertical bite reconstruction using direct resin composite restorations by private practitioners who attended a hands-on continuing education course on this technique. Materials and methods. In the years 2007 and 2008, 17 1-day continuing education courses on vertical bite reconstruction in the worn dentition by using direct resin composite restorations were attended by 310 participants. A 13-item questionnaire was posted to all course participants in April 2009 seeking information on the acceptance, implementation and experience of the presented technique in the private practice. Results. A total of 97 (31%) questionnaires were returned, whereas 67% of the respondents had used the presented technique. Analysis of the overall experience and satisfaction with the placed resin composite restorations using visual analog scale (VAS) revealed a mean VAS score of 7.2 ± 1.7 (0 = maximal unsatisfied, 10 = maximal satisfied). The direct resin composite restorations were predominantly rated ‘good’ within the assessed criteria surface texture, anatomical form, marginal integrity, marginal discoloration and color match. Ninety-eight percent of the private practitioners stated that they would continue to carry out vertical bite reconstructions according to this technique. The three most frequently observed clinical problems were related to marginal discolorations, bulk fractures and adhesive failures. Conclusion. The presented restoration method was well accepted by private practitioners who used this treatment approach at least once after course participation, even though some clinical problems were observed.     

Fabrication times for indirect composite resin restorations.

Fabrication times for indirect posterior composite resin restorations were recorded in a prospective clinical efficacy study. Four operators completed 132 one-visit inlays and onlays utilizing a new indirect posterior composite resin system (ICS). The mean time needed for the fabrication of one ICS restoration was 90 min, including the 'laboratory time'. When two restorations were provided simultaneously, the overall mean fabrication time was 120 min. The fabrication times were significantly influenced by the operator and the number of restorations. In several clinical phases a 40 per cent difference in mean fabrication time could be identified between operators. The extent of the restoration had no influence on mean fabrication time. The results of this study are considered to provide some indication of the cost-effectiveness of ICS restorations.     

A practice-based,randomized, controlled clinical trial of a new resin composite restorative: one-year results

This study evaluated the performance of a low-shrinking resin composite compared with an amalgam for restoration of Class I and II cavities of moderate size in posterior teeth in a general practice setting. Fifty-two pairs of test and control restorations were placed in 49 patients. Clinical evaluations and assessments of replica models were carried out at baseline, six months and one year. Patients recorded their level of satisfaction with the restorations by means of visual analog scales. Apart from one control restoration that failed due to a fractured cusp, all of the restorations reviewed at six months and one year were intact with no unacceptable scores for any of the evaluation criteria. It was concluded that the resin composite evaluated, when used in conjunction with the recommended adhesive system, may be an appropriate alternative to amalgam in the restoration of posterior teeth over one year in clinical service.     

Early failure of Class II resin composite versus Class II amalgam restorations placed by dental students

Using the information from remake request slips in a dental school's predoctoral clinic, we examined the short-term survival of Class II resin composite restorations versus Class II dental amalgam restorations. In the student clinic, resin composite is used in approximately 58 percent of Class II restorations placed, and dental amalgam is used in the remaining 42 percent. In the period examined, Class II resin composite restorations were ten times more likely to be replaced at no cost to the patient than Class II dental amalgam restorations. A total of eighty-four resin composite restorations and six amalgam restorations were replaced due to an identified failure.     

One-year observations on a composite resin for Class II restorations

A study was conducted to compare the clinical performance of a proprietary composite resin with that of amalgam when used in the restoration of Class II cavities. A total of 124 paired restorations were placed. The restorations were evaluated by a team from the United States Public Health Service, Materials &; Technology Branch, Division of Dental Health, San Francisco, Calif.     

Preference of temporary restorations and spacers: a survey of Diplomates of the American Board of Endodontists

The purpose of this investigation was to survey Diplomates of the American Board of Endodontists to determine their preferences in temporary restorations used during and following endodontic therapy and if cotton pellets are used as spacers. The survey asked which primary temporary material was used in anterior and posterior teeth to close access openings. Also, the endodontists were asked if they preferred a double seal and if they used cotton pellets as spacers. Eighty percent (507 of 603) of the surveys were returned. Cavit was the temporary restoration of choice for both anterior and posterior teeth, 48% and 54%, respectively. The majority of Diplomates, 83%, placed a cotton pellet beneath the temporary restorations.     

Marginal seal comparisons between resin-bonded Class II porcelain inlays, posterior composite restorations, and direct composite resin inlays

The microleakage of indirect porcelain and direct composite resin-bonded inlays was compared with that of posterior composite resin restorations using Class II preparations of extracted molar teeth. The resin-bonded inlay restorations provided a better marginal seal at the cervical restoration/dentin interface than did the composite resin restoration. The efficacy of this marginal seal varied with the particular treatments and materials used. Resin-bonded porcelain inlays had a higher incidence of cervical excess from the composite resin luting agent than did the posterior composite resin restorations.     

An evaluation of the performance of cast gold bonded restorations in clinical practice, a retrospective study

OBJECTIVES: To evaluate the performance of cast gold bonded restorations in clinical practice. MATERIALS AND METHODS: The records of all patients treated with cast gold bonded restorations between 1997 and 2004 of The Dental Hospital of Newcastle upon Tyne were reviewed. The following data were recorded: sex of patient, location of teeth (anterior or posterior), position of teeth (upper or lower) and type of cement (glass ionomer, zinc phosphate or resin cement). The survival time was calculated for each restoration; and the reason for failure (either debond or change of treatment plan) identified for each case. The restorations were stratified according to the age of the patient into 10-year age bands and survival analysis was used to identify variables associated with increased risk of failure. RESULTS: Restorations luted with resin cement showed the highest rate of survival after 7 years of follow-up. The alternative lutes had significantly worse survival (p<0.05). Restorations on anterior teeth had poorer survival than on posterior teeth but there were no differences between those placed in the mandible and the maxilla. CONCLUSIONS: Within the limitations of this study resin cements are most appropriate for this type of restoration with 80% survival at 7 years. Restorations placed on posterior teeth survived better.     

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复合树脂材料用于牙科已有20余年历史。这类材料既可用于前牙也可用于后牙。复合树脂发展到今天已经出现了许多专门应用于后牙的修复材料,并已取得满意的临床效果。银汞合金的许多缺点都可以为复合树脂所克服。因此,后牙复合树脂修复已为越来越多的患者和牙科医生所接受。然而,直接充填复合树脂材料仍旧被认为有许多局限性。比如边缘缺陷、面磨损、牙尖变形以及术后的牙髓敏感等。因此,近年来发展了复合树脂的一种新技术——间接性复合树脂嵌体与高嵌体修复技术。它的临床应用在某种程度上克服了上述直接充填树脂的局限性。复合树脂嵌体或高嵌体是作为固体黏固在预备洞型中的一种修复体。这种呈固态的修复体由复合树脂材料采用间接的方法制成,最后再黏固于口内。本文将最近的有关间接性复合树脂嵌体和高嵌体方面的资料进行综述,包括它的临床应用,优缺点以及面临的问题等。