Compomers as Class II restorations in primary molars

A variety of alternatives to amalgam are now available for use in class II restorations in primary teeth, including glass ionomer, composites, and intermediate materials such as compomer and resin modified glass ionomers (RMGI). The purpose of the present study was to evaluate the clinical performance of two compomers, Hytac and Dyract, and to compare these results to those reported for other intracoronal restorative materials. Evaluation after 24 months shows Hytac and Dyract to have performed well and comparably as class II restorations in primary teeth. The low failure rate, even in a population with a high caries increment, suggests that compomers are a suitable alternative to amalgam or other, tooth-colored materials when used as class II restorations in primary teeth.     

Clinical performance of Class II adhesive restorations in pulpectomized primary molars: 12-month results

The purpose of this report was to present the 12-month results of a prospective, randomized study evaluating the clinical and radiographic success rates of Class II adhesive restorations in pulpectomized primary molars. A total of 75 restorations were placed over root canal-treated primary molars, filled with a calcium hydroxide paste. The restorative systems tested were: (1) group 1: amalgam (negative control); (2) group 2: a hybrid resin composite (TPH, Dentsply) with prior acid conditioning and bonding with an etch-and-rinse adhesive (Prime&Bond NT, Dentsply); (3) group 3: a polyacid-modified resin composite (Dyract, Dentsply) bonded with Prime&Bond NT; (4) group 4: Dyract with prior nonrinse conditioner (NRC) treatment and bonding with Prime&Bond NT; and (5) group 5: a polyacid-modified resin composite (F2000) in conjunction with a self-etch adhesive (Prompt-L-Pop, 3M/ESPE). The restorations were evaluated clinically using the modified USPHS/Ryge criteria at 1, 2, 3, 4, 5, 6, 9, and 12 months. Radiographic evaluations were made in accordance with predetermined criteria. During the evaluation period, 12 teeth (group1=4, group2=1, group3=4, group4=3, and group5=2) were extracted due to radiographic evidence of failure. There was no difference between groups regarding the clinical evaluation criteria (P>.05) except marginal discoloration at 9 and 12 months (P<.05). The overall success rate at 12 months was 81% (group 1=73%, group 2=93%, group 3=73%, group 4=80%, and group 5=87%). Teeth restored with the resin composite+total-etch/bonding (group 2), followed by those with F2000+self-etch adhesive (group 5) exhibited the highest clinical and radiographic success rates. Radiographic failures observed beneath failed restorations were strongly suggestive of coronal microleakage.     

Clinical, radiographic, SEM evaluation and assessment of microleakage of Class II composite restorations

The influence of incremental or bulk filling techniques, and reapplication of unfilled resin (impregnation) to the margins with an enamel bonding agent, on marginal adaptation was evaluated in Class II composite restorations by clinical, radiographic, scanning electron microscope (SEM) and dye penetration techniques. Cavities were prepared in 80 extracted permanent posterior teeth. All cavity walls were treated with polyacrylic acid for 10 seconds. The enamel was etched for 1 minute, rinsed, dried, and lined with Scotchbond. Forty cavities were filled by increments of P30 and 40 cavities in bulk. The margins of the restorations of 20 teeth in each group were re-etched for 30 seconds and Concise Enamel Bond reapplied. The clinical scores were excellent for all restorations. Radiographic examination showed twice as many bubbles in the incrementally filled restoration than in the group filled in bulk. In 53 teeth, a radiolucent area between the dentin and the restorative material was found. After sectioning, this area was found to correspond to a hard material. The SEM revealed excellent margins in the groups of teeth that were impregnated with an unfilled resin, whereas 13 teeth without impregnation showed defective margins. The dye penetration, as a test for marginal leakage, was minimal at the occlusal surface of all teeth. At the cervical surface, 10.5% of the impregnated teeth showed severe dye penetration compared to 18% of the nonimpregnated teeth. No correlation was found between dye penetration at the cervical surface and the thickness of the residual enamel in this area.(ABSTRACT TRUNCATED AT 250 WORDS)     

Clinical evaluation of proximal contacts of Class II esthetic direct restorations.

OBJECTIVE: This study evaluated the effectiveness of proximal contacts in Class II restorations using two types of matrix bands (steel and polyester) with two different restoration techniques (incremental and with prepolymerized particles). METHOD AND MATERIALS: Eighty-eight Class II adjacent restorations using Prodigy resin composite were performed: 44 with the incremental technique (22 with steel matrix bands, 22 with polyester matrix bands) and 44 utilizing prepolymerized resin particles (22 steel matrix, 22 polyester matrix). The restorations were clinically evaluated at baseline and at 6, 12, and 18 months. Proximal contacts obtained immediately after restoration procedure in all restorations were satisfactory. RESULTS: No statistically significant alterations were found in 18 months of evaluation. CONCLUSION: Regardless of the utilized resin composite, there were no differences in the amount of proximal contact variations with respect to tested techniques and matrices.     

Assessment of marginal leakage around Class II composite restorations in retrieved primary molars

The aim of the present investigation was to evaluate, by means of dye penetration, the microleakage around Class II composite restorations, in retrieved primary molars that functioned in the mouth for at least one year. The experimental material consisted of 13 exfoliated primary molars that had been restored with Herculite (Kerr Corporation, Romulus, Michigan 48174 USA) at least one year previously, utilizing an incremental or a bulk filling technique. The retrieved teeth were insulated with utility wax and nail polish, immersed in 2% basic fuchsin, embedded in acrylic resin, and ground off to various depths. The marginal leakage was assessed according the degree of dye penetration at the occlusal and cervical margins. No difference was observed between the two filling techniques. In most teeth, no leakage at the occlusal margins was observed; minimal leakage, limited to the enamel, was observed at the occlusal margins of two teeth, one of each filling technique. Severe penetration was evident at the cervical margin of three restorations, two of them filled incrementally and the third using the bulk technique. Mild to moderate penetration was observed at the cervical margin in the majority of the other restorations. It was concluded that an incremental filling technique could not eliminate microleakage at the cervical margins of Class II composite restorations.     

Dyract versus Tytin Class II restorations in primary molars: 36 months evaluation.

Due to the changed treatment approach of proximal caries and the amalgam controversy, clinicians are in search for new materials. The aim of the present study was to compare amalgam with an adhesive material in deciduous molars in a clinical, split-mouth design study. At baseline 30 polyacid modified composite (Dyract) and 30 amalgam (Tytin) restorations were placed in primary molars, of which 24 and 17 could be evaluated after 24 and 36 months, respectively. Modified USPHS criteria were used for clinical evaluation every 6 months. Annual bite-wing radiographs were taken for evaluation of recurrent caries and cervical gap formation. In the present study, for Dyract as well as for Tytin restorations, low rates of recurrent caries were found, while Dyract restorations showed a better marginal adaptation and surface texture compared to Tytin restorations. In the Dyract group more radiolucencies were found at baseline. In both groups no patient complaint or pain was reported related to the radiolucencies. After 3 years the colour of Dyract was not comparable to the original. For Dyract no excessive wear was noticed compared to enamel. During the study one Dyract (recurrent caries: 18 months) and two Tytin (pulpal aetiology: 6 months, recurrent caries: 36 months) restorations had to be replaced. Even though the restorations were placed in caries risk children, at the 36 months' evaluation of this clinical study, the results indicate that Dyract can be an alternative for Tytin in the primary dentition.     

Microleakage of Class 2 glass-ionomer-silver restorations in primary molars.

The aims of this study were to assess microleakage at the cervical margins of class 2 "sandwich" restorations placed with two glass-ionomer-silver cements in primary molars, to compare the quality of the occlusal margins of these restorations to those prepared with Miracle Mix and Ketac Silver, and to assess by scanning electron microscopy (SEM) the marginal micromorphology of those restorations. Fifty-two class 2 restorations were prepared in extracted primary molars and were restored as follows: 1) Ketac Silver + Estilux Posterior (sandwich), 2) Miracle Mix + Estilux Posterior (sandwich), 3) Ketac Silver only, and 4) Miracle Mix only. No or minimal leakage was evident in most of the occlusal margins, whereas severe leakage was observed in almost 70% of the cervical margins of the Ketac Silver groups. Scanning electron microscopy evaluation demonstrated good adaptation at the buccal and lingual margins of all the restorations. Sixty-seven percent of the Miracle Mix restorations had no defects at the cervical margins, as opposed to only 17% of those with Ketac Silver.     

Ketac Molar Versus Dyract Class II restorations in primary molars: twelve month clinical results

The aim of the present clinical study was an in vivo evaluation of an improved conventional glass ionomer cement Ketac Molar (ESPE), compared to a polyacid modified composite resin, Dyract (Dentsply/De Trey), used in primary molars. Fifty-three Ketac Molar and fifty-two Dyract restorations were placed in box-only preparations in primary molars. The application time for the chemically cured Ketac Molar, was longer compared to the light-cured Dyract. In comparing the materials, no differences were found, comparing both materials regarding secondary caries, marginal adaptation, wear and fracture toughness. One case of recurrent caries adjacent to a Ketac Molar restoration and two cases in the Dyract group were reported. Two Ketac Molar restorations and one Dyract showed bulk fracture at the time of evaluation. At the twelve-month evaluation, no difference between the investigated materials was registered, which indicates that Ketac Molar can be used as a proximal restoration in the primary dentition. It should be emphasized, however, that one-year data should not be extrapolated to indicate the long-term success of restorations.     

Randomised trial of resin-based restorations in Class I and Class II beveled preparations in primary molars: 48-Month results

Objective

This randomised clinical trial evaluated the survival rate of resin-based restorations in Class I and Class II beveled preparations in primary molars, over 48 months.

Methods

Forty-eight children received 141 restorations in beveled cavosurface margin preparations in primary molars randomly assigned by a lottery method: 46 received treatment with Vitremer™ Tri-Cure Glass Ionomer System (33 Class I and 13 Class II restorations); 51 received treatment with Freedom™ (36 Class I and 15 Class II restorations); 44 received treatment with TPH Spectrum™ (30 Class I and 14 Class II restorations). Two calibrated examiners (weight κ ≥ 0.85) evaluated the restorations using the modified USPHS criteria and visible plaque index score at baseline and after 12, 24, 36 and 48 months. Cox regression with survival analysis and logistic regression evaluated the clinical performance of restorations.

Results

After 48 months, 11 teeth had exfoliated, 16 restorations were dropouts, 83 restorations were clinically successful of which 26 had used Vitremer™, 32 had used Freedom™ and 25 had used TPH Spectrum™. Thirty-one restorations failed because of secondary caries, fractures and loss of retention. The cumulative survival was 73.9%, 83.4% and 79.6%, respectively for Vitremer™, Freedom™ and THP Spectrum™ with no differences among materials (Log Rank Mantel-Cox, p > 0.05). However, the Class II cavity preparation reduced the survival of the restorations (OR = 5.1) for all materials evaluated (p > 0.05).

Conclusions

The life expectancy of Vitremer™, Freedom™ and THP Spectrum™ in Class I and Class II restorations could be comparable after 48 months.     

Survival of self-etch adhesive Class II composite restorations using ART and conventional cavity preparations in primary molars

PURPOSE: To test the null-hypothesis that there was no difference in the survival percentages of Class II composite restorations in primary teeth produced through either ART or conventional approaches after 2 years. METHODS: 157 children with 325 Class II cavitated dentin lesions were included in a split-mouth study design. A computer program randomly assigned cavitated dentin lesions to treatment groups stratified for gender, operator, upper/lower jaw and left/right side of the mouth. Three operators placed resin composite (Pertac II) restorations using a self-etch adhesive (Prompt L-Pop). Two independent examiners evaluated the restorations after 0.5, 1 and 2 years using the modified Ryge criteria. A modification of the actuarial survival method was applied to estimate survival percentages. RESULTS: There was no statistically significant difference (P > 0.05) observed between the cumulative survival percentages of Class II composite restorations in primary teeth produced by the two approaches after 2 years (ART: 34.9% +/- 4.7%; conventional: 35.1% +/- 4.7%). The cumulative survival percentages of ART and conventional Class II restorations of one of the operators were lower than for ART restorations of the other two operators and for conventional restorations of one of the operators (P < or = 0.001). The main reason for Class II composite restorations to fail over the 2-year period was complete loss of retention; ART: 75%; conventional: 77%. The null-hypothesis was accepted as there was no difference in the cumulative survival percentages of ART and conventional Class II composite restorations in primary teeth after 2 years. It appears that the low survival results obtained may have been caused by poor bonding of the self-etch adhesive.     

Evidence-based assessment of tooth-colored restorations in proximal lesions of primary molars

The purpose of this study was, using evidence-based dentistry, to compare the successes of glass ionomer cement (GIC), resin-modified GIC (RmGIC), composite resin (CR), and polyacid-modified composite resin (PAMCR) in primary molar proximal lesions. METHODS: The PICOT question was: P: in primary molar proximal lesions; I: does the use of 1 material (GIC, RmGIC, CR, or PAMCR); C: compared with the remaining materials; O (Outcome): result in higher success rates; T: when followed for at least 1 year? Relevant articles (256) were identified from databases then sieved by titles, abstracts, and full texts. Following exclusions, 36 dinical trials-including 25 randomized clinical trials (RCTs)-remained. Extracted data were meta-analyzed. RESULTS: GIC restorations had a significantly (P<.05) lower likelihood of success than RmGIC and CR restorations. Overall success rates were: (1) GIC (691 restorations)=75%; (2) RmGIC (276)=89%; (3) CR (620)=83%; (4) PAMCR (596)=87%. Mean success rates did not differ significantly (P>.05): (1) GIC (6 studies)=65+/-34%; (2) RmGIC (3 studies)=93+/-7%; (3) CR (7 studies)=85+/-12%; and (4) PAMCR (8 studies)=90+/-10%. CONCLUSIONS: Few articles were available to determine the best material. Recognizing material improvements since 1990, earlier data may be noncomparable. RmGIC had the highest success rates, but fewest studies and fewest restorations; only one product was assessable. Prospective RCTs should be of at least 5 years' duration to determine correctly the success rate of Class II restorations in primary molars.     

Clinical performance and SEM evaluation of direct composite restorations in primary molars

PURPOSE: To evaluate the clinical outcome of composite restorations performed in primary molars after 18 months and the morphology of the dentin/resin interface. METHODS: 41 primary molars from children aged 4-9 years were restored with Scotchbond Multi-Purpose Plus adhesive system and Z100 resin-based composite. The restorations were evaluated at baseline, 6, 12 and 18 months using the USPHS method for direct clinical analysis. Plaster models were made at each evaluation period for indirect evaluation. For the morphologic analysis of the dentin/resin interface, seven exfoliated teeth were sectioned longitudinally in a mesio/distal direction and observed in the electro scanning electron microscope. RESULTS: 100% (n = 40) of the restorations evaluated at 6 months were scored as Alpha for anatomical form, color matching, secondary caries, color alteration, and marginal degradation. At 12 months, 96.4% (n = 28) of the restorations received Alpha score and 3.4% Charlie score. At 18 months, all restorations evaluated (27/27) received Alpha score. 23 restorations were indirectly evaluated at 6, 12 and 18 months postoperatively. No significant wear or fractures were observed in any of the restorations. In the evaluation of the dentin/resin interface, the formation of a consistent hybrid layer was observed and the restorations were well adapted to the dentin at 18 months postoperatively.     

Conventional versus resin-modified glass-ionomer cement for Class II restorations in primary molars. A 3-year clinical study

Summary. Objective. To compare the clinical performance of two glass‐ionomer cements (GICs)for Class II restorations in primary molars: a conventional cement (Fuji II®) and a resin‐modified cement (Vitremer®). Design. Split mouth and random assignment to the two materials were used for the majority of the molars. Sample and methods. Forty consecutive 4–7‐year‐old children were included. One operator made 115 restorations: 53 with Vitremer and 62 with Fuji II. The restorations were evaluated clinically, radiographically and from colour photographs. Results. The cumulative success rate of the Vitremer restorations was 94% and that of the Fuji II restorations 81%. The difference is statistically significant. The risk of a failed restoration was more than five times higher with Fuji II than with Vitremer as the restorative material. Of the 13 unsuccessful restorations, seven had lost their retention, four had secondary caries, and two were fractured. Conclusions. The resin‐modified GIC offered advantages over the conventional GIC for restoring approximal caries in primary molars.     

The teaching of Class I and II restorations in primary molars: a survey of North American dental schools.

PURPOSE: The purpose of this study was to obtain an overview of materials and restoratives techniques taught for Class I and Class II restorations in primary molars in different pediatric dentistry departments in North America. METHODS: A form with response alternatives was mailed to 63 dental schools in the United States and Canada. The forms were addressed to the chairman/undergraduate program director of the department of pediatric dentistry. Questions regarding the restorative materials taught, indications and contraindications for the use of tooth-colored materials and the type of cavity preparation indicated for those materials were among the topics assessed. RESULTS: Eighty-six percent of the dental schools responded to the survey. Amalgam continues to be the material of choice for Class I and II restorations in primary molars, although hybrid composites and compomers are gaining some popularity. When tooth-colored materials were indicated, the slot-type of cavity preparation was the preferred one. CONCLUSIONS: The diversity in teaching may reflect uncertainty related to requirements for optimal restorations of primary teeth. Data from dental schools of other countries may be important to obtain to establish universally accepted criteria and standards for restorative techniques of primary teeth.