Jan W.V. van Dijken

Selection of dental materials and longevity of replaced restorations in Public Dental Health clinics in northern Sweden.

OBJECTIVES To investigate the selection of direct restorative materials and longevity of replaced restorations in relation to operator and patients characteristics. METHODS A cross-sectional study of treatment in practice, recording all new placements and replacements of direct restorations was performed during 2 weeks comprising all dentists within the Public Dental Health clinics in the county council of Västerbotten. RESULTS A total of 2834 data collection sheets, one for each placed restoration, were received with a dropout of 10%. Restorations analyzed in the study were placed in permanent teeth in patients older than 15 years. First restorations placed due to primary caries were 671 and replacements 1536. Class II was the most frequently treated cavity followed by class I. The median longevity of replaced restorations was for amalgam, resin based composite and glass ionomer 16, 6 and 11 years, respectively. High caries risk patients showed shorter longevity for resin based composite restorations than low or moderate risk patients. Secondary caries as reason for failure for class II resin based composite restorations occurred significantly later than loss or fracture. Significantly longer longevity was observed for replaced restorations executed by more experienced dentists. CONCLUSIONS The use of amalgam was negligible and the material was predominantly replaced by resin based composites in first and replaced restorations. Class II was the most frequent placed and replaced restorations. Caries risk and experience of operator influenced longevity of replacements.

A clinical evaluation of anterior conventional, microflller, and hybrid composite resin fillings: A 6-year follow-up study

Anterior resin fillings of seven composite resin materials—two conventional, two hybrid, and three microflller—were evaluated over a 6-year period. Extrinsic discoloration, color match, marginal discoloration, marginal adaptation, surface roughness, and recurrent caries were investigated. The individual caries increment was compared with an estimation of the expected caries risk of the individuals. The estimation was based on the net effect of microbial counts, oral hygiene, salivary flow rates, buffer values, and fermentable carbohydrate intake. The variation of the investigated factors within each resin group was too great to enable combination of the results. The individual materials are therefore presented and compared. Unacceptable color match scores after 6 years varied markedly among the brands (3.5%-79.7%). Unacceptable marginal discoloration was seen in 1.7% of the restorations, whereas unacceptable marginal adaptation varied between 13.7% and 37.3% for the brands. Recurrent caries occurred at th...

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

OBJECTIVES To 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. METHODS All 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. RESULTS Totally 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. SIGNIFICANCE Posterior 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.

Durability of resin composite restorations in high C-factor cavities: A 12-year follow-up

OBJECTIVE Polymerization shrinkage and shrinkage stress has been considered as one of the main disadvantages of resin composite restorations. Cavities with high C-factors increase the risk for interfacial failures. Several restorative techniques have been suggested to decrease the shrinkage stress. The purpose of this study was to evaluate the durability of techniques as oblique layering, indirect curing and/or a laminate with a poly-acid modified resin composite in direct Class I resin composite restorations in a 12-year follow-up. METHODS Each of 29 patients received one or two pair(s) rather extensive Class I restorations. The first restoration was a poly-acid modified resin composite/resin composite sandwich restoration and the second a direct resin composite restoration. Both restorations, except for the laminate layer, were placed with oblique layering and two-step curing technique. 90 restorations were evaluated annually with slightly modified USPHS criteria during 12 years. RESULTS At 12 years, 38 pairs were evaluated. Two cases of slight post-operative sensitivity were observed in one patient. A cumulative failure rate of 2.4% was observed for both the resin composite and the laminate restorations. One laminate restoration showed non-acceptable color match, but was not replaced and one resin composite restoration showed a chip fracture. Five restorations were replaced due to primary proximal caries. CONCLUSIONS The high failure rate expected in the high C-factor Class I cavity, associated with polymerization shrinkage and shrinkage stress, were not observed. The techniques used resulted in an excellent durability for the Class I resin composite restorations.

Five-year survival of 3-unit fiber-reinforced composite fixed partial dentures in the anterior area

OBJECTIVES The purpose of this clinical study was to evaluate the long-term outcome of 3-unit anterior fixed partial dentures (FPDs) made of fiber-reinforced resin composite (FRC), and to identify design factors influencing the survival rate. METHODS 52 patients (26 females, 26 males) received 60 indirectly made FRC FPDs, using pre-impregnated unidirectional glass fibers, requiring manual wetting, as framework material. FPDs were surface (n=48) or hybrid (n=12) retained and mainly located in the upper jaw. Hybrid FPDs had a combination of retainers; i.e. crown at one and surface retention at the other abutment tooth. Surface FPDs were either purely adhesively retained (n=29) or with additional mechanical retention (n=19). Follow-up period was at minimum 5 years, with check-ups every 1-2 years. Six operators were involved, in three centers in the Netherlands, Finland and Sweden. Survival rates, including repairable defects of FPDs, and success rates were determined. RESULTS Kaplan-Meier survival rate at 5 years was 64% (SE 7%). For the level of success, values were 45% (SE 7%) and the estimated median survival time 58 (SE 10.1) months. For surface FPDs, additional mechanical retention did not improve survival significantly. There was a trend towards better survival of surface FPDs over hybrid FPDs, but differences were not significant. Main failure modes were fracture of the FPD and delamination of veneering composite. SIGNIFICANCE A success rate of 45% and a survival rate of 64% after 5 years was found. Fracture of the framework and delamination are the most prevalent failure modes, especially for surface FPDs.

A 6-year evaluation of a direct composite resin inlay/onlay system and glass ionomer cement-composite resin sandwich restorations.

van Dijken JWV. A 6-year evaluation of a direct composite resin inlay/onlay system and g. iass ionomer cement-composite resin sandwich restorations. Acta Odontol Scand 1994;52:368-376. Oslo. ISSN 0001-6357The most undesirable characteristic of composite resin is its polymerization shrinkage. Two techniques developed to counter this problem are the Composite inlay and the sandwich composite filling. The durability of 100 direct composite inlays and 34 closed and 16 open sandwich composite fillings made with a conventional glass ionomer cement were evaluated during a 6-year period in a group of low and high caries risk patients. Modified USPHS criteria were used. Six inlays (6%), 5 closed sandwich fillings (14.7%), and 12 open sandwich fillings (75%) needed replacement. Six other inlays and three closed sandwich fillings showed non-acceptable defects that could be repaired with composite resin. The direct composite inlays showed very good clinical durability, whereas the open sandwich filling with conventio...

An evaluation of the radiopacity of composite restorative materials used in Class I and Class II cavities

The radiopacity of 28 shades of 18 composite brands, recommended for use in Class I and Class II cavities, and one amalgam were tested in accordance with the instructions in the latest draft standards of ISO for resin-based filling materials. The composition of the inorganic fillers in the materials was analyzed by optical emission spectroscopy. Twelve composites showed radiopacity greater than enamel, for five the radiopacity was lower than that of dentin, and for two materials the radiopacity was between that of enamel and dentin. The optical emission spectroscopy analyses showed a large variety in the composition of the fillers. The elements added to increase radiopacity in the composite materials are barium, strontium, zinc, zirconium, and ytterbium.

Longevity of posterior resin composite restorations in adults - A systematic review

OBJECTIVE To conduct a systematic review of the literature on the longevity of posterior resin composite restorations in adults. MATERIAL AND METHODS A systematic literature search was conducted according to pre-determined criteria for inclusion and exclusion. The studies selected were prospective clinical trials with a minimum follow-up time of 4 years, 40 restorations per experimental group and an annual attrition rate of less than 5%. Initially, abstracts and full-text articles were assessed independently and the assessment was subsequently agreed on by five reviewers. The methodological quality of the studies was assessed according to the Swedish Council on Health Technology Assessment (SBU) standard checklist for determining the extent to which studies meet basic quality criteria. RESULTS In all, the literature search identified 4275 abstracts and 93 articles were read in full-text. There were eighteen studies which met the criteria for inclusion, eight of which were included in the analysis. There were 80 failures of restorations with a total follow-up time at risk for failure of 62,030 months. The overall incidence rate for all causes of failure was 1.55 lost restorations per 100 restoration years. The most common biological reason for failure (a total of 31 restorations) was secondary caries, with or without fracture of the restoration. The quality of the evidence was low. CONCLUSIONS In an efficacy setting, the overall survival proportion of posterior resin composite restorations is high. The major reasons for failure are secondary caries and restoration fracture which supports the importance of adequate follow-up time. CLINICAL SIGNIFICANCE The overall survival proportion of posterior composite restorations was high, but the results cannot be extrapolated to an effectiveness setting. The importance of adequate follow-up time is supported by the finding that secondary caries often occurred after 3 years or later.

Three-year comparison of fired ceramic inlays cemented with composite resin or glass ionomer cement

Ceramic inlays offer a good alternative to posterior composites, which still show a high polymerization shrinkage. The thin cement layer will reduce the total amount of shrinkage and probably result in a better marginal adaptation and decreased marginal leakage. Fired feldspathic ceramic inlays cemented with either a glass ionomer cement or a dual-cured composite resin luting cement were compared intraindividually. During a 3-year period 118 inlays, 59 in each group, were examined. Eleven inlays were evaluated as non-acceptable during the period: two (3.4%) in the composite resin group and nine (15.3%) in the glass ionomer cement group. In the composite group one inlay fractured partially and one inlay was replaced because of postoperative sensitivity. In the glass ionomer group four inlays were totally lost, and partial fractures occurred in five inlays. In the fractured glass ionomer cemented inlays the cement was still in place in the cavities. Eight patients reported post-operative sensitivity. No secondary caries was detected around the inlays even though 46% of the patients were considered high caries risk patients.

A randomized controlled three year evaluation of “bulk-filled” posterior resin restorations based on stress decreasing resin technology

OBJECTIVE The objective of this randomized controlled prospective clinical trial was to evaluate the efficacy of a flowable resin composite (SDR) bulk fill technique in posterior restorations and to compare it intraindividually with a conventional 2 mm resin composite curing technique in a 3-year follow up. MATERIALS AND METHODS Thirty-eight pairs Class II and 15 pairs Class I restorations were placed in 38 patients with a mean age of 55.3 years (range 32-87). Each patient received at random at least two, as similar as possible, Class II or Class I restorations of two restorative techniques. In all cavities a single step self-etch adhesive (Xeno V) was applied. In one of the cavities of each pair, a flowable resin composite (SDR) was placed, in bulk increments up to 4 mm as needed to fill the cavity 2 mm short of the occlusal cavosurface. The occlusal part was completed with a nano-hybrid resin composite (Ceram X mono) layer. In the second cavity, the hybrid resin composite was placed in 2 mm increments. The restorations were evaluated using slightly modified USPHS criteria at baseline and then yearly during 3 years. Caries risk and parafunctional habits of the participants were estimated. RESULTS After three years, 76 Class II and 28 Class I restorations could be observed. One molar resin composite-only tooth showed post-operative sensitivity during 3 weeks for temperature changes and occlusal forces. Two failed Class II molar restorations in the resin composite-only group were observed during the first year, one cusp fracture and one resin composite fracture. An annual failure rate of 1.3% was found for the resin composite only restorations and of 0% in the bulk-filled restorations (n.s.). Ten participants were estimated as having high caries risk and eleven showed active bruxing habits. SIGNIFICANCE The 4 mm bulk-fill technique with the flowable resin composite SDR showed highly clinical effectiveness, which was comparable during the 3-year follow-up with the 2mm resin composite layering technique.