Clinical evaluation of paired compomer and glass ionomer restorations in primary molars: final results after 42 months

Tooth-coloured materials for class II restorations in primary molars: systematic review and meta-analysis

PURPOSE

The aim of this systematic review was to compare the success rate of five tooth-coloured materials, namely Glass Ionomer (GI), Resin-Modified Glass Ionomer (RMGI), Composite Resin (CR), Polyacid-Modified Composite Resin or Compomer (CO) and High-Viscosity Glass Ionomer (HVGI) in primary molar Class II restorations.

METHODS

Five databases were searched from inception to April 23, 2020 for randomized clinical trials comparing the failure rate of these materials. After duplicate study removal, data extraction and risk of bias assessment with the Cochrane tool, data synthesis was conducted, comparing all five tooth-coloured materials in pairs and computing the overall success rate for each one, respectively.

RESULTS

A total of 5615 articles were obtained by electronic and hand literature search. After the application of the eligibility criteria, ten RCTs were included in this systematic review and six RCTs for meta-analysis. Their risk of bias was assessed to be high to moderate. Due to the small number of RCTs comparing the five restorative materials in pairs investigated in the same study, only three MAs were available for heterogeneity assessment. These were: (1) between CO-RMGI (RR 1.04 [0.59, 1.84]; p = 0.88; I² = 1%), (2) CR-CO (RR 1.12 [0.41, 3.02]; p = 0.83; I² = 57%), and (3) between CR-RMGI (RR 1.10 [0.74, 1.63]; p = 0.65; I² = 0%). No statistically significant differences were found between the two materials in all three comparisons.

CONCLUSION

CR, RMGI and CO presented no statistical differences. In comparison to other tooth-coloured materials, studies on GI were too few to allow recommendations about its use. More studies on HGVI are needed for evidence-based recommendations to be made. The evidence extracted from this meta-analysis was not strong enough (moderate), due to the small number of RCTs and the risk of bias ranging from high to moderate. More, well-designed RCTs comparing tooth-coloured materials for primary molar Class II restorations are necessary.

Comparative Evaluation of the Fracture Strength of Pulpotomized Primary Molars: An In Vitro Study

PURPOSE

This study evaluates the fracture strength of pulpotomized primary molars restored with amalgam, miracle mix, cermet, resin-modified glass ionomer cement, and nanocomposites.

MATERIALS AND METHODS

Fifty primary first and second molars were collected for this study. All the teeth were randomly divided into five groups (n = 10). Standard pulpotomy cavities were prepared. Teeth were air dried and the canal orifices were capped with a layer of zinc oxide eugenol. A lining of calcium hydroxide was placed over it. Amalgam, miracle mix, cermet, resin-modified glass ionomer cement, and nanocomposite were placed in groups I, II, III, IV, and V, respectively. All the samples were then subjected to the fracture strength test using the universal testing machine and the results were statistically analyzed.

RESULTS

All the groups were compared by the ANOVA one-way test which indicated that there were statistically significant differences among the five groups.

CONCLUSION

Nanocomposites can be considered to be the best restorative material in terms of fracture strength among amalgam, miracle mix, cermet, and resin-modified glass ionomer cement.

HOW TO CITE THIS ARTICLE

Mohammad N, Pattanaik S, et al. Comparative Evaluation of the Fracture Strength of Pulpotomized Primary Molars: An In Vitro Study. Int J Clin Pediatr Dent 2019;12(1):5-9.

Can onlay's be an alternative restoration for severely damaged primary teeth

Objective:

The aim of this study was to evaluate indirect compomer and composite resin onlay restorations of severely damaged primary molars in vivo.

Materials and Methods:

At the study, 48 restorations, in seven girls and ten boys totally 17 patients aged 4–8, was evaluated clinically with using USPHS criteria for 15 months.

Results:

The study results revealed that the clinical success rate of compomer and composite onlay restorations was 79% and 96%, respectively. No significant differences were found statistically between the materials.

Conclusions:

In the children severely damaged primary molars, onlays are usually worked with an indirect technique in clinics. One of the advantages of indirect technique is being most similar to its original form morphologically.

WITHDRAWN: Dental fillings for the treatment of caries in the primary dentition

BACKGROUND

Childhood caries (tooth decay) consists of a form of tooth decay that affects the milk teeth (also known as baby or primary teeth) of children. This may range from tooth decay in a single tooth to rampant caries affecting all the teeth in the mouth. Primary teeth in young children are vital to their development and every effort should be made to retain these teeth for as long as is possible. Dental fillings or restorations have been used as an intervention to repair these damaged teeth. Oral health professionals need to make astute decisions about the type of restorative (filling) material they choose to best manage their patients with childhood caries. This decision is by no means an easy one as remarkable advances in dental restorative materials over the last 10 years has seen the introduction of a multitude of different filling materials claiming to provide the best performance in terms of durability, aesthetics, symptom relief, etc when placed in the mouth. This review sought to compare the different types of dental materials against each other for the same outcomes.

OBJECTIVES

The objective of this review was to compare the outcomes (including pain relief, survival and aesthetics) for restorative materials used to treat caries in the primary dentition in children.  Additionally, the restoration of teeth was compared with extraction and no treatment.

SEARCH METHODS

Electronic searches of the following databases were undertaken: the Cochrane Oral Health Group's Trials Register (up to January 2009); CENTRAL (The Cochrane Library 2009, Issue1); MEDLINE (1966 to January 2009); EMBASE (1996 to January 2009); SIGLE (1976 to 2004); and conference proceedings on early childhood caries, restorative materials for paediatric dentistry, and material sciences conferences for dental materials used for children's dentistry (1990 to 2008). The searches attempted to identify all relevant studies irrespective of language.Additionally, the reference lists from articles of eligible papers were searched, handsearching of key journals was undertaken, and personal communication with authors and manufacturers of dental materials was initiated to increase the pool of suitable trials (both published and unpublished) for inclusion into this review.

SELECTION CRITERIA

Randomised controlled trials (RCTs) or quasi-randomised controlled trials with a minimum period of 6 months follow up were included. Both parallel group and split-mouth study designs were considered. The unit of randomisation could be the individual, group (school, school class, etc), tooth or tooth pair. Included studies had a drop-out rate of less than 30%. The eligible trials consisted of young children (children less than 12 years) with tooth decay involving at least one tooth in the primary dentition which was symptomatic or symptom free at the start of the study.

DATA COLLECTION AND ANALYSIS

Data were independently extracted, in duplicate, by two review authors. Disagreements were resolved by consultation with a third review author. Authors were contacted for missing or unclear information regarding randomisation, allocation sequence, presentation of data, etc. A quality assessment of included trials was undertaken. The Cochrane Collaboration statistical guidelines were followed for data analysis.

MAIN RESULTS

Only three studies were included in this review. The Fuks 1999 study assessed the clinical performance of aesthetic crowns versus conventional stainless steel crowns in 11 children who had at least two mandibular primary molars that required a crown restoration. The outcomes assessed at 6 months included gingival health (odds ratio (OR) 0.3; 95% confidence interval (CI) 0.01 to 8.32), restoration failure (OR 3.29; 95% CI 0.12 to 89.81), occlusion, proximal contact and marginal integrity. The odds ratios for occlusion, proximal contact and marginal integrity could not be estimated as no events were recorded at the 6-month evaluation. The Donly 1999 split-mouth study compared a resin-modified glass ionomer (Vitremer) with amalgam over a 36-month period. Forty pairs of Class II restorations were placed in 40 patients (21 males; 19 females; mean age 8 years +/- 1.17; age range 6 to 9 years). Although the study period was 3 years (36 months), only the 6- and 12-month results are reported due to the loss to follow up of patients being greater than 30% for the 24- and 36-month data. Marks 1999a recruited 30 patients (age range 4 to 9 years; mean age 6.7 years, standard deviation 2.3) with one pair of primary molars that required a Class II restoration. The materials tested were Dyract (compomer) and Tytin (amalgam). Loss to follow up at 24 and 36 months was 20% and 43% respectively. This meant that only the 24-month data were useable. For all of the outcomes compared in all three studies, there were no significant differences in clinical performance between the materials tested.No studies were found that compared restorations versus extractions or no treatment as an intervention in children with childhood caries.

AUTHORS' CONCLUSIONS

It was disappointing that only three trials that compared three different types of materials were suitable for inclusion into this review. There were no significant differences found in all three trials for all of the outcomes assessed. Well designed, randomised controlled trials comparing the different types of filling materials for similar outcomes are urgently needed in dentistry. There was insufficient evidence from the three included trials to make any recommendations about which filling material to use.

Materials for Paediatric Dentistry. Part 1: Background to the Treatment of Carious Primary Teeth

Dental caries is a disease that affects many people, including children, and presents numerous challenges to healthcare providers. As clinicians it is important that we consider the advantages and disadvantages of treating carious primary teeth, and make an informed decision about when it is appropriate or not. This paper describes the background to the treatment of carious primary teeth, looking at the differences between primary and permanent teeth, and the relevance of this. It also suggests points to consider when looking at restoration survival studies, as the ability to appraise the literature critically is important for us all in this 'evidence-based' age. CPD/Clinical Relevance: Our early life experiences have the ability to shape our future attitudes and behaviour. Children with carious teeth require careful management so that pain and suffering is minimized, and positive attitudes towards dentistry are fostered.

Materials for Paediatric Dentistry. Part 2: The Evidence

Which materials should be used to restore primary teeth? The second part in this series summarizes the current evidence base relating to this question, and describes the biological approach to caries management. CPD/Clinical Relevance: Our decisions regarding material choices should be based, where possible, on up-to-date evidence. This will help to ensure that the appropriate material is placed in the appropriate clinical scenario.

INVESTIGATING THE MANAGEMENT OF CARIOUS PRIMARY TEETH IN GENERAL DENTAL PRACTICE: AN OVERVIEW OF THE DEVELOPMENT AND CONDUCT OF THE FICTION TRIAL

The management of carious primary teeth is a challenge for patients, parents and clinicians. Most evidence supporting different management strategies originates from a specialist setting and therefore its relevance to the primary care setting is questionable. The UK National Institute for Health Research (NIHR) Health Technology Assessment (HTA) has commissioned the FiCTION (Filling Children's Teeth: Indicated Or Not?) trial; a multi-centre primary dental care randomised controlled trial (RCT) to determine the most clinically and cost- effective approach to managing caries in the primary dentition in the UK. This large trial began in 2012, is due to be completed in late 2017 and involves 72 practices and 1,124 children initially aged three to seven years with dentine caries, following randomisation to one of three caries management strategies. Clinical, radiographic, quality of life, treatment acceptability and health economics data are collected during the three-year follow up period. This article provides an overview of the development and conduct of FiCTION and discusses some approaches adopted to manage challenges and achieve the patient recruitment target.

Comparative evaluation of microleakage of three restorative glass ionomer cements: An in vitro study

Purpose:

The aim of this study was to compare the microleakage of glass ionomers (conventional and resin modified) with that of recently introduced nanoionomers.

Materials and Methods:

Standardized class I and class V cavities were prepared on 120 young permanent teeth. Samples were equally divided into group I (class I restorations) and group II (class V restorations), and further divided into subgroups. The subgroups were restored with Fuji IX, Fuji II LC, and newly introduced Ketac^™ N 100 (KN 100). Samples were thermocycled and submerged in Acridine dye for 24 h. Samples were sectioned to view under fluorescent microscope and marginal leakage was evaluated by Chi-square and Kruskal — Wallis test.

Results:

Fuji IX showed the maximum leakage, followed by LC II and the least was observed in KN 100. In class I restorations, there was significant difference while comparing Fuji IX with Fuji LC II and KN 100 and nonsignificant difference between LC II and KN100. In class V restorations, Fuji IX and KN100, KN 100 and LC II showed significant difference. Fuji IX and LC II showed nonsignificant difference.

Conclusion:

Within the limitations of this study, Fuji IX showed the maximum microleakage. KN 100 showed minimum leakage, better sealing ability, and was more consistent.

Influence of dental care on children's oral health and wellbeing

BACKGROUND

Dental problems in early childhood can have a very significant effect not only on the oral health of young children but on their quality of life and that of their families. Added to this are the long term risks they carry into the permanent dentition.

AIM

To review current literature on the management of early childhood caries and its influence on wider oral and general health.

RESULTS

Recent studies suggest that the risks for dental caries, periodontal disease, malocclusion and other general health problems including overweight and obesity may be increased in children who have had early childhood caries. Traditional restoration of damaged primary teeth has been shown to have only moderate outcomes depending on the techniques and materials used and the ability of children to cooperate because of age or other factors.

CONCLUSIONS

More recent interesting approaches that seal enamel caries, only partially remove carious dentine or attempt to entirely seal carious dentine lesions merit not only discussion but also longer term investigation. With increasing demands on health funding, dentistry must look at how the most appropriate care can be provided to allow children to reach adulthood with healthy permanent dentitions - something that less than half the population currently achieve.

Restorative dentistry for children

This article discusses contemporary pediatric restorative dentistry. Indications and contraindications for the choice of different restorative materials in different clinical situations, including the risk assessment of the patient, are presented. The specific use of glass ionomer cement or resin-modified glass ionomer cement, resin-based composite, and stainless steel crowns is discussed so that preparation design and restoration placement is understood.

Restoration of class II cavities in primary molar teeth with conventional and resin modified glass ionomer cements: a systematic review of the literature

AIM

To review the literature concerning the restoration of primary teeth with glass ionomer (GIC) or resin modified glass ionomer cement (RMGI) used in conventional class II cavities.

METHODS

A search of the literature identified through Medline between 1966 and 2006 using the key words: glass ionomer, resin modified, glass polyalkenoate, deciduous/primary teeth. Studies that used ART or tunnel preparations were excluded. Papers of relevant clinical studies (prospective and retrospective) were assessed and graded using predetermined criteria. Papers were graded according to the number of criteria met as (A >90%, B1 = 75%, B2 = 50%, C <50%).

RESULTS

The search identified 411 papers, from which an application of the inclusion criteria yielded 20 studies. Of these, 2 were rated B1 and 18 B2. Failure rates varied from 6.6% to 60% for GIC, and from 2% to 24% for RMGI.

CONCLUSION

GIC cannot be recommended for class II cavities in primary molars. There is evidence that RMGIC can perform successfully in small to moderate sized class II restorations.

A Comparative Evaluation of Marginal Leakage of Different Restorative Materials in Deciduous Molars: An in vitro Study

Context: Microleakage around dental restorative materials is a major problem in clinical dentistry. Inspite of many new restorative materials available in the market very few actually bond to the tooth surface.

Aims: The aims of this study were: (1) To evaluate and compare the marginal leakage of newer restorative materials viz colored compomer, ormocer, giomer and RMGIC in class I restoration of deciduous molars. (2) To compare the microleakage scores between the groups of: Colored compomer and ormocer, giomer and RMGIC, ormocer with giomer and RMGIC, giomer with RMGIC.

Materials and methods: A total of 40 primary molars were randomly divided into four groups of 10 each. Class I cavities were prepared and the cavities were restored with colored compomer (Group A), Ormocer (Group B), Giomer (Group C) and RMGIC (Group D). The teeth were thermocycled and subjected to 0.5% basic fuchsin dye penetration followed by sectioning. The cut sections were evaluated under a stereomicroscope and the data was subjected to statistical analysis.

Statistical analysis used: Mann-Whitney U test and Student t-test.

Results: No significant difference was observed when colored compomer was compared to ormocer, giomer and RMGIC. Ormocer showed significantly lower microleakage when compared to giomer. However, no significant difference was observed when ormocer was compared to RMGIC. No significant difference between giomer and RMGIC was found.

Conclusion: Ormocer has proven to be an excellent restorative material as it showed least microleakage followed by colored compomer, giomer and RMGIC in increasing order.

How to cite this article: Yadav G, Rehani U, Rana V. A Comparative Evaluation of Marginal Leakage of Different Restorative Materials in Deciduous Molars: An in vitro Study . Int J Clin Pediatr Dent 2012;5(2):101-107.

Dental fillings for the treatment of caries in the primary dentition

BACKGROUND

Childhood caries (tooth decay) consists of a form of tooth decay that affects the milk teeth (also known as baby or primary teeth) of children. This may range from tooth decay in a single tooth to rampant caries affecting all the teeth in the mouth. Primary teeth in young children are vital to their development and every effort should be made to retain these teeth for as long as is possible. Dental fillings or restorations have been used as an intervention to repair these damaged teeth. Oral health professionals need to make astute decisions about the type of restorative (filling) material they choose to best manage their patients with childhood caries. This decision is by no means an easy one as remarkable advances in dental restorative materials over the last 10 years has seen the introduction of a multitude of different filling materials claiming to provide the best performance in terms of durability, aesthetics, symptom relief, etc when placed in the mouth. This review sought to compare the different types of dental materials against each other for the same outcomes.

OBJECTIVES

The objective of this review was to compare the outcomes (including pain relief, survival and aesthetics) for restorative materials used to treat caries in the primary dentition in children. Additionally, the restoration of teeth was compared with extraction and no treatment.

SEARCH STRATEGY

Electronic searches of the following databases were undertaken: the Cochrane Oral Health Group's Trials Register (up to January 2009); CENTRAL (The Cochrane Library 2009, Issue1); MEDLINE (1966 to January 2009); EMBASE (1996 to January 2009); SIGLE (1976 to 2004); and conference proceedings on early childhood caries, restorative materials for paediatric dentistry, and material sciences conferences for dental materials used for children's dentistry (1990 to 2008). The searches attempted to identify all relevant studies irrespective of language.Additionally, the reference lists from articles of eligible papers were searched, handsearching of key journals was undertaken, and personal communication with authors and manufacturers of dental materials was initiated to increase the pool of suitable trials (both published and unpublished) for inclusion into this review.

SELECTION CRITERIA

Randomised controlled trials (RCTs) or quasi-randomised controlled trials with a minimum period of 6 months follow up were included. Both parallel group and split-mouth study designs were considered. The unit of randomisation could be the individual, group (school, school class, etc), tooth or tooth pair. Included studies had a drop-out rate of less than 30%. The eligible trials consisted of young children (children less than 12 years) with tooth decay involving at least one tooth in the primary dentition which was symptomatic or symptom free at the start of the study.

DATA COLLECTION AND ANALYSIS

Data were independently extracted, in duplicate, by two review authors. Disagreements were resolved by consultation with a third review author. Authors were contacted for missing or unclear information regarding randomisation, allocation sequence, presentation of data, etc. A quality assessment of included trials was undertaken. The Cochrane Collaboration statistical guidelines were followed for data analysis.

MAIN RESULTS

Only three studies were included in this review. The Fuks 1999 study assessed the clinical performance of aesthetic crowns versus conventional stainless steel crowns in 11 children who had at least two mandibular primary molars that required a crown restoration. The outcomes assessed at 6 months included gingival health (odds ratio (OR) 0.3; 95% confidence interval (CI) 0.01 to 8.32), restoration failure (OR 3.29; 95% CI 0.12 to 89.81), occlusion, proximal contact and marginal integrity. The odds ratios for occlusion, proximal contact and marginal integrity could not be estimated as no events were recorded at the 6-month evaluation. The Donly 1999 split-mouth study compared a resin-modified glass ionomer (Vitremer) with amalgam over a 36-month period. Forty pairs of Class II restorations were placed in 40 patients (21 males; 19 females; mean age 8 years +/- 1.17; age range 6 to 9 years). Although the study period was 3 years (36 months), only the 6- and 12-month results are reported due to the loss to follow up of patients being greater than 30% for the 24- and 36-month data. Marks 1999a recruited 30 patients (age range 4 to 9 years; mean age 6.7 years, standard deviation 2.3) with one pair of primary molars that required a Class II restoration. The materials tested were Dyract (compomer) and Tytin (amalgam). Loss to follow up at 24 and 36 months was 20% and 43% respectively. This meant that only the 24-month data were useable. For all of the outcomes compared in all three studies, there were no significant differences in clinical performance between the materials tested.No studies were found that compared restorations versus extractions or no treatment as an intervention in children with childhood caries.

AUTHORS' CONCLUSIONS

It was disappointing that only three trials that compared three different types of materials were suitable for inclusion into this review. There were no significant differences found in all three trials for all of the outcomes assessed. Well designed, randomised controlled trials comparing the different types of filling materials for similar outcomes are urgently needed in dentistry. There was insufficient evidence from the three included trials to make any recommendations about which filling material to use.

Clinicians choices of restorative materials for children

BACKGROUND

Recently, there has been an expansion in the range of tooth-coloured restorative materials available. In 1999, the National Health and Medical Research Council recommended clinicians use alternatives to amalgam in children 'where appropriate'.

METHODS

A three-part 29-item questionnaire was developed, tested in a focus group, and distributed to members of the Australasian Academy of Paediatric Dentistry (AA; paediatric dentists and paediatric dentistry postgraduate students; n=55), and the Australian and New Zealand Society of Paediatric Dentistry, Victorian Branch (SPD; general dentists and dental therapists; n=50). Participant information, material choices, and six hypothetical clinical scenarios were addressed.

RESULTS

The overall response rate was 74 per cent. For both groups, the first ranked factor influencing choice of restorative material for vital primary teeth was child age, and caries experience for vital first permanent molars. For moderate-sized Class I and II restorations in primary molars, a tooth-coloured material was chosen by 92 and 84 per cent respondents respectively. For restoring two separate proximal lesions in a primary molar, 65 per cent chose a tooth-coloured material followed by a stainless steel crown (27 per cent; all AA members), then amalgam (8 per cent). The SPD respondents were significantly more likely to choose glass ionomer cement for Class I and II restorations and for restoring two proximal lesions (all p=0.000) in primary molars than AA respondents, who were more likely to choose composite resins/compomers or amalgam/stainless steel crowns for these restorations. Younger respondents (21-40 years) were significantly more likely to choose composite resins/compomers or amalgam/stainless steel crowns (p=0.048) than older respondents (41-65 years), who were likely to choose glass ionomer cement.

CONCLUSIONS

For Class I and II restorations in primary molars, glass ionomer cement was the material chosen most frequently (SPD respondents); preference for amalgam or stainless steel crowns was low (both SPD and AA groups). The wide range of materials chosen for the hypothetical clinical scenarios suggests the need for guidelines on selection of restorative materials, and the need for longitudinal studies to follow actual clinical outcomes of the materials chosen.

Flowable resin composite as a class II restorative in primary molars: A two-year clinical evaluation

OBJECTIVE

To evaluate the clinical durability of flowable resin composite and resin-modified glass ionomer cement when used as class II restoratives in primary molars.

MATERIAL AND METHODS

A total of 190 restorations were placed in 61 children, age in the range of 5-11 years. The restoratives, Tetric Flow, in combination with the adhesives, Excite or Prompt-L-Pop and Vitremer, were used in class II cavities in primary molars. An intra-individual study design was used and the restorations were evaluated by modified USPHS criteria over a 2-year period.

RESULTS

146 of the restorations could be evaluated at 2 years. The cumulative failure rate was 10.6% for Vitremer and 13.6% for Tetric Flow. No statistically significant differences were found in failure rates between different materials or between bonding systems. The main cause of failure for Tetric Flow was secondary caries and for Vitremer wear and dissolution.

CONCLUSIONS

Vitremer and Tetric Flow showed no significant difference concerning clinical durability at 2 years when used as class II restoratives in primary molars. Both materials demonstrated acceptable clinical results.

Clinical evaluation of composite and compomer restorations in primary teeth: 24-month results

PURPOSE

This split-mouth, blind study evaluated the clinical performance of Dyract AP, F2000, and Heliomolar placed in primary molars of 30 children (mean age, 6 years and 2 months).

MATERIALS AND METHODS

From a total of 79 restorations accomplished, 27 were built with Heliomolar (18 Class I, and 9 Class II), 30 were with F2000 (21 Class I and 9 Class II), and 22 were built with Dyract AP (14 Class I and 8 Class II). All of teeth restored had primary caries lesions. At 6, 12, 18 and 24 months, 60 restorations (75%) were evaluated using USPHS criteria for: color match (CM), marginal adaptation (MA), marginal discoloration (MD), anatomic form (AF) and secondary caries (SC) by three calibrated operators. The Alpha+Bravo score percentage was considered as clinical success. The data were subjected to statistical analysis by Mann-Whitney and Kruskal-Wallis tests (p<0.05).

RESULTS

Heliomolar showed the smallest success clinical at 12 months for marginal adaptation and secondary caries, and at 18 months for marginal discoloration. Regarding color match and anatomic form, no significant differences were found among the groups at each evaluation period. When materials were compared, Heliomolar did not show a significant difference among the evaluated periods for any criteria, remaining with the lowest scores. Significant differences were observed at 12 months for F2000 (marginal adaptation), and at 24 months for Dyract AP (marginal discoloration and secondary caries) and for F2000 (color match and marginal discoloration).

CONCLUSIONS

It was concluded that Dyract AP and F2000 showed the best clinical performance over 24 month-evaluations for marginal discoloration and secondary caries, and color match and marginal adaptation, respectively. The use of the resin composite Heliomolar in Class I/II restorations in primary molars should be carefully considered.

A novel technique using preformed metal crowns for managing carious primary molars in general practice - a retrospective analysis

BACKGROUND

There is a high level of untreated dental decay in primary teeth in Scotland. Despite evidence for the efficacy of preformed metal crowns (PMCs) for the restoration of primary molars, few are placed in general practice, possibly due to the interventive nature of the clinical procedure. There is, however, a novel way of placing PMCs involving no local anaesthesia, no caries removal and no preparation of the tooth: the Hall technique.

AIM

To investigate the survival of carious primary teeth treated with PMCs placed using a novel, simplified method - the Hall technique.

SETTING

General dental practice, in Scotland.

METHOD

A retrospective analysis of practice records from one general practitioner, from 1988 to 2001. The majority of the 978 PMCs fitted on 259 children, using the Hall technique, were placed when there was clinical evidence of approximal caries into dentine. The Kaplan-Meier approach was used to analyse survival times and the Mantel-Haenszel Log rank test for comparison between tooth types.

RESULTS

For all tooth types, the probability of surviving three years without being extracted or the PMC being lost, was 73.4% (95% confidence interval 70.1% to 76.4%), and for five years was 67.6% (95% confidence interval 63.3% to 71.5%). The probability of surviving without extraction alone for three years was 86.0% (95% confidence interval 83.2% to 88.4%), and for five years was 80.5% (95% confidence interval 76.5% to 83.9%).

CONCLUSIONS

Hall technique restorations placed on primary molars with decay clinically into dentine, by a single operator in general dental practice, have a similar success rate to some other, more conventional, restorative techniques. The technique requires further evaluation through a prospective randomised control clinical trial before its use could be generally recommended.

Review on fluoride-releasing restorative materials--fluoride release and uptake characteristics, antibacterial activity and influence on caries formation

OBJECTIVES

The purpose of this article was to review the fluoride release and recharge capabilities, and antibacterial properties, of fluoride-releasing dental restoratives, and discuss the current status concerning the prevention or inhibition of caries development and progression.

METHODS

Information from original scientific full papers or reviews listed in PubMed (search term: fluoride release AND (restorative OR glass-ionomer OR compomer OR polyacid-modified composite resin OR composite OR amalgam)), published from 1980 to 2004, was included in the review. Papers dealing with endodontic or orthodontic topics were not taken into consideration. Clinical studies concerning secondary caries development were only included when performed in split-mouth design with an observation period of at least three years.

RESULTS

Fluoride-containing dental materials show clear differences in the fluoride release and uptake characteristics. Short- and long-term fluoride releases from restoratives are related to their matrices, setting mechanisms and fluoride content and depend on several environmental conditions. Fluoride-releasing materials may act as a fluoride reservoir and may increase the fluoride level in saliva, plaque and dental hard tissues. However, clinical studies exhibited conflicting data as to whether or not these materials significantly prevent or inhibit secondary caries and affect the growth of caries-associated bacteria compared to non-fluoridated restoratives.

SIGNIFICANCE

Fluoride release and uptake characteristics depend on the matrices, fillers and fluoride content as well as on the setting mechanisms and environmental conditions of the restoratives. Fluoride-releasing materials, predominantly glass-ionomers and compomers, did show cariostatic properties and may affect bacterial metabolism under simulated cariogenic conditions in vitro. However, it is not proven by prospective clinical studies whether the incidence of secondary caries can be significantly reduced by the fluoride release of restorative materials.

Relative curing degree of polyacid-modified and conventional resin composites determined by surface Knoop hardness

OBJECTIVES

The aim of the present study was to investigate the relative curing degree at a depth of 2 mm of several polyacid-modified composites (PAM-Cs) as a function of shade.

METHODS

The Knoop hardness of the irradiated top and non-irradiated bottom surfaces of 2 mm thick samples of the PAM-Cs Hytac, F2000, Glasiosite, Dyract, Dyract AP, and Compoglass F and of the resin composites Z100, Herculite Enamel XRV, and Durafill VS, were determined for shades A2 and A4.

RESULTS

The top and bottom hardness of F2000 and Glasiosite ranged between that of the two composites Herculite and Z100. Compoglass, Dyract and Dyract AP had a lower top and bottom hardness than the hybrid composites, but higher than that of the microfilled composite Durafill. The top hardness of Hytac compared with that of the first group, whereas the bottom hardness compared with the second group. The bottom-to-top KHN ratio reflecting the relative curing degree at a depth of 2 mm was less than 80% for the two shades of Hytac and Compoglass as well as for the A4 shade of Dyract AP and Herculite.

SIGNIFICANCE

A hard top surface of a PAM-C is not an indication of adequate in depth polymerization. Shade A2 results in significantly greater values for the curing degree compared to shade A4, the effect depending quantitatively on the formulation of the material. Some formulations of PAM-C do not reach an adequate curing degree at a depth of 2 mm so that it is recommended to apply the incremental technique even in box-only cavities with layers of maximum 2 mm.

Obtaining an evidence-base for clinical dentistry through clinical trials

Ideally, all clinical practice should be based on the best available evidence; however, in general dental practice even a very routine issue, such as the appropriate management of the carious primary dentition, is hampered by the lack of a sound evidence-base from high quality clinical trials run in general dental practices. Furthermore, the use of the evidence that is available may be confounded by inadequate reporting. This paper reviews the difficulties reported in successfully completing such clinical trials, and reports on the authors' own experiences. Suggestions are made for overcoming the challenge of patient recruitment in randomised controlled clinical trials in primary dental care. These include: regular contact with a principal investigator, who is viewed as a peer; ensuring the relevance of the research topic to the dentists' daily practice; appropriate remuneration; acknowledgement of the contribution made and recognition of the contribution of research activity to continuing professional development. Use of the CONSORT statement to improve planning and reporting of clinical trials is recommended.

Restoration materials for primary molars—results from a European survey

OBJECTIVE

The aim of this study was to obtain an overview of the materials and restorative techniques taught for Class I and Class II restorations in primary molars of different European departments for paediatric dentistry and to compare the results to those for North America.

METHODS

The forms were sent to the chairmen of the departments of paediatric dentistry or-when included into the department for operative dentistry-to the director of 200 universities in 32 European Countries. The questions concerned the preferred materials and techniques, as well as the indications or contraindications for the use of the different tooth coloured materials.

RESULTS

Forty-three percent of the universities from western European countries (excluding Germany) responded to the survey. A 97% answer rate was obtained from German Schools. Of the other European regions, the response rate varied remarkably (24-54%). Also, opinions on materials used and methods applied were different from country to country. Only in a few regions (Eastern Europe), amalgam remains the filling material of first choice for Class I and II cavities in primary molars, whereas in others, the use has been restricted and tooth coloured materials, especially compomers or resin-modified glass ionomer cements, are being preferred.

CONCLUSIONS

Great diversity in teaching was observed not only among the European countries, but also within the countries themselves which makes it difficult to compare the results of our study to the ones obtained from the US.

Partial caries removal and cariostatic materials in carious primary molar teeth: a randomised controlled clinical trial

OBJECTIVE

To determine the durability and effectiveness of a black copper cement (BCC) and a conventional glass ionomer cement (GIC) when used to restore primary molars following partial caries removal (PCR) and to compare these results with conventional cavity preparation and restoration.

DESIGN

Split-mouth randomised controlled clinical trial.

SETTING

Department of Paediatric Dentistry, Dundee Dental Hospital, Dundee, 1998-1999.

SUBJECTS

Patients with previously unrestored, matched carious cavities in non-pulpally involved primary molars.

INTERVENTIONS

Three treatment groups: (1) Partial caries removal followed by lining with BCC and restoration with GIC (PCR:BCC); (2) Partial caries removal and restoration with GIC alone (PCR:GIC), and (3) Complete caries removal and conventional restoration (CR). Restoration durability and effectiveness was assessed both clinically and radiographically over 24 months.Main outcome measures Median survival time (MST) of restorations.

RESULTS

Forty-four patients (F: 31; M: 13), mean age 6.8 years (range: 3.7-9.5), had 120 restorations placed (PCR:GIC: 43; CR: 41; PCR:BCC: 36). Eighty-six molars (29 patients) (PCR:GIC: 30; CR: 29; PCR:BCC: 27) were reviewed at 24 months. The median survival times (MST) with 25% and 75% quartiles in parenthesis were as follows: PCR:BCC, MST = 24 months (6, 24); PCR:GIC, MST = 24 months (24, 24) and CR, MST = 24 months (24, 24). The MST for PCR:BCC restorations was significantly less than for PCR:GIC and CR restorations (W = 1163.5, P = 0.028 and W = 1081.0, P = 0.004 respectively).

CONCLUSION

There were no differences in the proportions of restorations lost between restoration types, although PCR:BCC restorations did have significantly more abscess/sinus formation over the 24-month study period.

Effect of filler fraction on strength, viscosity and porosity of experimental compomer materials

OBJECTIVE

The primary goal is to develop a self-cured polyacid-modified resin composite with good mechanical and rheological properties. To achieve such a goal, the aim of this study is to determine how volume filler fraction (VFF) affects mechanical properties and viscosities of such materials containing different filler volumes.

METHODS

A series of self-cured polyacid-modified composites made from polyacid modified resins and TEGDMA, mixed with filler particles, were evaluated regarding compressive strength (CS), diametral compressive strength (DCS) and viscosity. The maximum filler content, which could be incorporated into the materials, was calculated from CS tests as well as from viscosity measurements using Mooney's equation. Porosity contents were also determined in an attempt to explain different failure behaviours.

RESULTS

The CS values peaked at 18.9 vol.% filler particles and declined afterwards for self-cured polyacid-modified resin composites cured in air. Using photopolymerisation and barium filler in the polyacid-modified resin composites resulted in the highest CS and DCS values. The viscosity increased continuously with increased VFF. VFF results determined experimentally and with Mooney's equation at shear rates of 0.01, 0.1, 1.0, and 10.0 s(-1) revealed that the maximal filler fraction values were 54.9+/-1.8, 55.9+/-1.3, 56.3+/-0.9, and 56.8+/-0.8 vol.%, respectively. The largest porosity content occurred at a VFF value of 53 vol.%

CONCLUSIONS

We conclude that an increase in filler fraction of the investigated experimental polyacid-modified resin composite materials above a certain value (20-30 vol.%) does not result in improved mechanical properties.

The survival and clinical performance of resin-based composite restorations used to treat localised anterior tooth wear

OBJECTIVE

To examine the clinical performance of resin-based composite restorations placed at an increased vertical dimension when used to manage localised anterior tooth wear.

DESIGN

A retrospective analysis of cases treated at a single centre.

SETTING

UK Hospital setting in the year 2000.

SUBJECTS AND METHODS

Two hundred and twenty five restorations placed in 31 subjects were included. Assessment was made following examination of study casts and projected slides. Modified United States Public Health Services criteria were used and data analysed using the software Statistical Programme for Social Sciences (SPSS). Survival analysis was carried out at two levels, major failure only and all types of failure. Kaplan-Meier survival plots were produced against different variables and modes of failure were also noted.

RESULTS

Major failure requiring replacement of the restoration was uncommon within the first five years. Minor failure requiring repair or refinishing presented mainly as wear, marginal discolouration or marginal fracture. Median survival was 4 years 9 months when all types of failure were considered. The restorations have good appearance and are well tolerated.

CONCLUSION

Placement of resin-based composite restorations at an increased vertical dimension to treat localised anterior tooth wear, has good short to medium term survival. The technique is conservative and relatively easy to maintain.

Clinical performance of a compomer and amalgam for the interproximal restoration of primary molars: a 24-month evaluation

OBJECTIVES

To evaluate the clinical performance of a compomer material (Dyract) in comparison with dental amalgam (Contour) for management of proximal caries in primary molars in young children.

SETTING

General dental practice, and a dental hospital paediatric clinic.

METHOD

This was a prospective study. A split mouth design was used with identical pairs of minimal Class II cavities, of matched tooth type in the same dental arch, usually diagnosed with the use of bitewing radiographs. Seventy-eight pairs of restorations were completed of which 60 pairs were available for evaluation after 24 months.

RESULTS

Comparable retention rates were observed for both Dyract and amalgam. The retention rates were high for both materials, with only four amalgam and two Dyract restorations failing over 24 months. Significantly better marginal integrity (P < 0.05) was observed for Dyract compared with amalgam with no significant differences between the two materials for recurrent caries, wear or surface texture.

CONCLUSIONS

Dyract seemed to be a suitable alternative to amalgam for proximal restorations in primary molars of young children for use in general dental practice.

Hygroscopic expansion of a compomer and a composite on artificial gap reduction

OBJECTIVE

This study compared the effect of water sorption on the extent of marginal gap reduction in a compomer (Dyract AP, Dentsply) and a composite (Spectrum, Dentsply) over a 12-week storage period.

MATERIALS AND METHODS

Artificial gaps were created in 40 borosilicate glass cylinders, each 5mm deep and with an internal diameter of 5.5mm. Half of the internal bonding surface of each cylinder was sandblasted, silanised and coated with a dentine adhesive (Prime&Bond NT, Dentsply). Twenty partially bonded cylinders were incrementally filled with Dyract AP (AP) and the rest with Spectrum (S). For each material, 10 specimens were stored in de-ionised water (W), and 10 (control) in non-aqueous silicone fluid (O) at 37 degrees C. The dimension of the same maximum gap created in each specimen was repeatedly measured at 0, 1, 2, 4, 6, 8, 10 and 12 weeks, using a light microscope under incident light at 570x magnification. Gap widths in each of the four groups (n=10) were statistically compared. Correlations between mean gap width reduction and storage time were also examined.

RESULTS

Friedman repeated measures ANOVA on ranks revealed significant differences (p<0.001) among the gap widths measured at different time intervals in groups AP-W and S-W. No significant differences (p>0.05) were found in groups AP-O and S-O. Tukey's multiple comparison test indicated that no significant differences (p>0.05) were detectable beyond the sixth week in AP-W and the fourth week in S-W. Linear regression analyses showed that mean gap widths decreased exponentially with time for AP-W (r=0.97) and S-W (r=0.90). From the slopes of the regression lines, the rate of marginal gap reduction in AP-W was 4.6 times faster than S-W.

CONCLUSION

Marginal gap reduction in both the materials are directly attributed to water sorption and that the reduction is larger and more rapid in Dyract AP.