Effectiveness of Single-surface ART Restorations in the Permanent Dentition: A Meta-analysis

Comparative Evaluation of the Survival Rates of Atraumatic Restorative Treatment Restorations Using Bilayer Technique along with Nanofilled Coating in Primary Molars: A Clinical Study

Objective

To enhance the survival rate of atraumatic restorative treatment (ART) restorations using (class I and class II) bilayer technique of placing glass ionomer cement (GIC) along with nanofilled coating (NC) over the restorations, thereby improving longevity.

Study design

A total of 178 primary molars in 67 children were selected and randomly divided into four groups. Group IA was treated with a single layer of GIC, followed by a protective layer of petroleum jelly in class I restoration. Group IB was treated with a single layer of GIC, followed by a protective layer of petroleum jelly in class II restoration. Group IIA was treated with bilayer GIC restoration followed by NC of GC-Coat Plus in class I, whereas group IIB was treated with bilayer GIC restoration followed by GC-Coat Plus in class II. Clinical analysis of all three groups was performed at 1, 3, 6, 9, and 12 months to evaluate the success of treatment procedures using predetermined criteria. Pearson's Chi-square and Kaplan-Meier estimates were utilized to evaluate the success of all four treatment procedures (p < 0.05).

Results

Out of 178 teeth, 33 teeth were in group IA, 36 teeth were in group IB, 43 teeth were in group IIA, and 40 teeth were available for evaluation at the end of the 12-month follow-up period. The overall success was determined to be 81% for group IA, 79.2% for group IB, 79.5% for group IIA, and 88.6% for IIB. At 6th-month follow-up, one clinical failure was observed in groups IA and IB. At 9 months follow-up, two clinical failures were observed in both group IA and group IB and three failures were observed in group IIB. At 12 months follow-up, four clinical failures were observed in group IA, three in group IB and one clinical failure was observed in group IIB. There was no statistically significant difference observed between the success of the four groups, suggesting that either of the techniques can be utilized for ART.

Conclusion

No statistically significant difference was observed between the survival of class I and class II restorations of both the groups, indicating that either single-layer or bilayer technique along with NC can be adopted for the management of dental caries in primary molars using the ART approach.

How to cite this article

Khan N, Garg N, Garg N, et al. Comparative Evaluation of the Survival Rates of Atraumatic Restorative Treatment Restorations Using Bilayer Technique along with Nanofilled Coating in Primary Molars: A Clinical Study. Int J Clin Pediatr Dent 2024;17(S-1):S55-S60.

Effect of Fluoride-based Varnishes with Added Calcium and Phosphate on Microhardness of Esthetic Restorative Materials: An In Vitro Study

Background and objectives

Fluoride varnishes are being used to prevent caries in children. The high concentration of fluoride in varnishes apart from caries prevention may cause changes in surface properties of esthetic restorations. The study aims to evaluate and compare the effect of four commercially available fluoride varnishes with added calcium and phosphate on microhardness of three esthetic materials namely conventional GIC (Fuji II), high viscosity GIC (Fuji IX), and nanocomposite (Filtek Z350).

Materials and methods

A total of 28 pellets were made of each material and stored in distilled water at 37 °C for 48 hours. The microhardness of the pellets was tested which served as a baseline. These were then randomly divided into four subgroups. In one subgroup Profluorid varnish was applied, second subgroup MI varnish was applied, third subgroup Embrace varnish was applied, and in the fourth subgroup Enamel Pro varnish was applied as per protocol. Thereafter, all the pellets were subjected to microhardness testing (load = 100 g for 15 seconds).

Results

The fluoride varnishes increased the microhardness of conventional GIC (Fuji II) whereas in case of high viscosity GIC (Fuji IX) the application of varnishes reduced the microhardness. In case of nanocomposite restorative material (Filtek Z350) only Profluorid varnish increased its microhardness.

Conclusion

Fluoride varnish and calcium-phosphate containing fluoride varnish effect on the microhardness of restorative material is material dependent. So, the choice of fluoride varnish with or without proprietary additives depends on the nature and composition of the restorative material.

How to cite this article

Shetty RS, Bhat SS, HK Sundeep, et al. Effect of Fluoride-based Varnishes with Added Calcium and Phosphate on Microhardness of Esthetic Restorative Materials: An In Vitro Study. Int J Clin Pediatr Dent 2022;15(2):187-193.

Should local drug delivery systems be used in dentistry?

In dentistry, the use of biomaterial-based drug delivery systems (DDS) aiming the release of the active compounds directly to the site of action is slowly getting more awareness among the scientific and medical community. Emerging technologies including nanotechnological platforms are offering novel approaches, but the majority are still in the proof-of-concept stage. This study critically reviews the potential use of DDS in anesthesiology, oral diseases, cariology, restorative dentistry, periodontics, endodontics, implantology, fixed and removable prosthodontics, and orthodontics with a special focus on infections. It also stresses the gaps and challenges faced. Despite numerous clinical and pharmacological advantages, some disadvantages of DDS pose an obstacle to their widespread use. The biomaterial's biofunctionality may be affected when the drug is incorporated and may cause an additional risk of toxicity. Also, the release of sub-therapeutic levels of drugs such as antibiotics may lead to microbial resistance. Multiple available techniques for the manufacture of DDS may affect drug release profiles and their bioavailability. If the benefits outweigh the costs, DDS may be potentially used to prevent or treat oral pathologies as an alternative to conventional strategies. A case-by-case approach must be followed.

CariesCare International adapted for the pandemic in children: Caries OUT multicentre single-group interventional study protocol

Background

Comprehensive caries care has shown effectiveness in controlling caries progression and improving health outcomes by controlling caries risk, preventing initial-caries lesions progression, and patient satisfaction. To date, the caries-progression control effectiveness of the patient-centred risk-based CariesCare International (CCI) system, derived from ICCMS™ for the practice (2019), remains unproven. With the onset of the COVID-19 pandemic a previously planned multi-centre RCT shifted to this “Caries OUT” study, aiming to assess in a single-intervention group in children, the caries-control effectiveness of CCI adapted for the pandemic with non-aerosols generating procedures (non-AGP) and reducing in-office time.

Methods

In this 1-year multi-centre single-group interventional trial the adapted-CCI effectiveness will be assessed in one single group in terms of tooth-surface level caries progression control, and secondarily, individual-level caries progression control, children’s oral-health behaviour change, parents’ and dentists’ process acceptability, and costs exploration. A sample size of 258 3–5 and 6–8 years old patients was calculated after removing half from the previous RCT, allowing for a 25% dropout, including generally health children (27 per centre). The single-group intervention will be the adapted-CCI 4D-cycle caries care, with non-AGP and reduced in-office appointments’ time. A trained examiner per centre will conduct examinations at baseline, at 5–5.5 months (3 months after basic management), 8.5 and 12 months, assessing the child’s CCI caries risk and oral-health behaviour, visually staging and assessing caries-lesions severity and activity without air-drying (ICDAS-merged Epi); fillings/sealants; missing/dental-sepsis teeth, and tooth symptoms, synthetizing together with parent and external-trained dental practitioner (DP) the patient- and tooth-surface level diagnoses and personalised care plan. DP will deliver the adapted-CCI caries care. Parents’ and dentists’ process acceptability will be assessed via Treatment-Evaluation-Inventory questionnaires, and costs in terms of number of appointments and activities. Twenty-one centres in 13 countries will participate.

Discussion

The results of Caries OUT adapted for the pandemic will provide clinical data that could help support shifting the caries care in children towards individualised oral-health behaviour improvement and tooth-preserving care, improving health outcomes, and explore if the caries progression can be controlled during the pandemic by conducting non-AGP and reducing in-office time.

Trial registration: Retrospectively-registered-ClinicalTrials.gov-NCT04666597-07/12/2020: https://register.clinicaltrials.gov/prs/app/action/SelectProtocol?sid=S000AGM4&selectaction=Edit&uid=U00019IE&ts=2&cx=uwje3h. Protocol-version 2: 27/01/2021.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12903-021-01674-1.

Glass Ionomer Sealants Can Prevent Dental Caries but Cannot Prevent Posteruptive Breakdown on Molars Affected by Molar Incisor Hypomineralization: One-Year Results of a Randomized Clinical Trial

To evaluate the preventive effect of glass ionomer cement (GIC) against dental caries and posteruptive breakdown (PEB) on molars affected by molar incisor hypomineralization (MIH). In this randomized clinical trial, 77 children aged 5-9 years with at least 1 MIH-affected molar and without PEB or dentin caries lesions (n = 228) were included and randomly allocated to one of the following groups: (1) MIH-affected molars that remained unsealed and (2) MIH-affected molars that received GIC sealants. Dental caries and PEB were clinically evaluated after 6 and 12 months. Associations between dental caries and PEB with independent variables were evaluated using logistic regression analysis (p < 0.05). The MIH-affected molars allocated to the GIC sealant group were less likely to develop dental caries compared to those allocated to the unsealed group (OR = 0.23; 95% CI 0.06-0.95). Conversely, application of a GIC sealant was not associated with prevention of PEB (p = 0.313). Furthermore, MIH-affected molars presenting yellow-brown opacities were almost 5 times more likely to develop dental caries (p = 0.013) and PEB (p = 0.001) compared to those presenting white-creamy opacities. We can conclude that GIC sealants can prevent dental caries on MIH-affected molars; however, the same protective effect was not observed for PEB.

A comparative survival analysis of high viscosity glass ionomer restorations using conventional cavity preparation and atraumatic restorative treatment technique in primary molars: A randomized clinical trial

Background:

This randomized clinical trial (RCT) aimed to compare the 3-year survival rates of high viscosity glass ionomer restorations (HVGIC) using conventional cavity preparation and atraumatic restorative technique (ART) in primary molars.

Materials and Methods:

In this RCT, 139 schoolchildren aged 6–9 years with dentinal caries in primary molars were randomly allocated to groups, i.e. the ART group and the conventional group, utilizing a random number generator. Adequate allocation concealment was done. Intervention was delivered using standard procedure and GC Fuji IX ART HVGIC was used as restorations in both the groups. Analysis was carried in 92 participants, and survival rates in both the groups were compared at 12, 24, and 36-month intervals. IBM SPSS software was utilized to analyze the time taken for the procedure and the Kaplan–Meier estimate was used to assess the survival rates. P value of 0.05 was considered statistically significant.

Results:

The ART took longer to complete (16.48 ± 2.02 min) versus conventional rotary instrumentation (13.15 ± 1.32 min). The conventional method was slightly superior as compared to ART; excellent survival rates (i.e. >90%) were achieved in both groups at the end of 12-month follow-up with no significant differences at the end of 24 and 36 months as evident from Kaplan–Meier estimate (P = 0.255).

Conclusion:

Three-year follow-up showed that GIC restorations with ART and conventional method carried out using GC Fuji IX ART HVGIC were acceptably successful, substantiating the use of ART for the primary dentition in areas with high caries prevalence and limited access to dental care.

Atraumatic restorative treatment compared to the Hall Technique for occluso-proximal carious lesions in primary molars; 36-month follow-up of a randomised control trial in a school setting

BACKGROUND

Atraumatic Restorative Treatment (ART) and the Hall Technique (HT) are both minimally invasive, non-aerosol generating procedures (non-AGPs). They seem to have never been directly compared, nor has the HT been studied in a non-clinical setting. This study compared the HT and ART restorations placed in a school setting after 36 months.

METHODS

Children (5-10 yo) who had a primary molar with a dentinal occluso-proximal, cavitated carious lesion were allocated to the ART (selective removal) or HT arms.

PRIMARY OUTCOME

restoration survival over 36-months (using Kaplan-Meier survival analysis, log rank test, and Cox regression).

SECONDARY OUTCOMES

(1) occlusal vertical dimension (OVD) (1, 2, 3, 4 weeks) and (2) child self-reported discomfort; (3) treatment acceptability (immediately following interventions); (4) Child Oral Health Related Quality of Life (OHRQoL), before treatment and after 6 months and (5) a post hoc analysis of time to tooth exfoliation (1, 6, 12, 18, 24, 30, 36 months).

RESULTS

One-hundred and thirty-one children (ART = 65; HT = 66) were included (mean age = 8.1 ± 1.2). At 36 months, 112 (85.5%) children were followed-up.

PRIMARY OUTCOME

restoration survival rates ART = 32.7% (SE = 0.08; 95% CI 0.17-0.47); HT = 93.4% (0.05; 0.72-0.99), p < 0.001; Secondary outcomes: (1) OVD returned to pre-treatment state within 4 weeks; (2) treatment discomfort was higher for the HT (p = 0.018); (3) over 70% of children and parents showed a high acceptability for treatments, with crown aesthetics being a concern for around 23% of parents; (4) Child OHRQoL improved after 6 months; and (5) teeth treated with the HT exfoliated earlier than those in the ART group (p = 0.007).

CONCLUSIONS

Both ART and the HT were acceptable to child participants and their parents and all parents thought both restorations protected their child's tooth. However, the crown appearance concerned almost a quarter of parents in the HT arm. Children experienced less discomfort in the ART group. Although both treatments can be performed in a non-clinical setting and have the advantage of being non-aerosol generating procedures (non-AGPs), the HT had almost three times higher survival rates (93.4%) for restoring primary molar occluso-proximal cavities compared to ART (32.7%).

TRIAL REGISTRATION

This trial was registered in ClinicalTrials.gov (NCT02569047), 5th October 2015. https://clinicaltrials.gov/ct2/show/study/NCT02569047?cond=Hall+Technique+Atraumatic+Rest orative+Treatment&draw=2&rank=2.

Antimicrobial properties, compressive strength and fluoride release capacity of essential oil-modified glass ionomer cements-an in vitro study

OBJECTIVES

This study was designed to investigate the antimicrobial properties, compressive strength and fluoride release capacities of high-viscous glass ionomer cements (GICs) after incorporation of cinnamon and thyme essential oils.

MATERIALS AND METHODS

Experimental-modified GICs were prepared by incorporation of thyme and cinnamon essential oils into the liquid phase of the cement at 5 and 10% v/v. Antimicrobial activity against selected microorganisms (Streptococcus mutans and Candida albicans) was done using direct contact test. Compressive strength of the four new formulations and control group was tested using a universal testing machine while fluoride ion release was measured by ion-selective electrode at 1, 7, 14 and 28 days. Data analysis and comparisons between groups were performed using factorial and one-way ANOVA and Tukey's tests.

RESULTS

All newly formulated GICs exhibited significantly higher inhibitory effects against both Streptococcus mutans and Candida albicans growth when compared to conventional GIC (p < 0.05). Compressive strength of 5% cinnamon-modified GIC (MPa = 160.32 ± 6.66) showed no significant difference when compared with conventional GIC (MPa = 165.7 ± 5.769) (p value > 0.05). Cumulative fluoride-releasing pattern at days 7, 14, and 28 were 10% cinnamon-GIC > 5% thyme-GIC > 5% cinnamon-GIC > 10% thyme GIC > conventional GIC.

CONCLUSIONS

Incorporation of 5% cinnamon oil into glass ionomer resulted in better antimicrobial effects against S. mutans and C. albicans and increased fluoride-release capacity without jeopardizing its compressive strength.

CLINICAL RELEVANCE

The 5% cinnamon-modified GIC appears to be a promising alternative restorative material in ART technique.

Efficacy of GC Gold Label 9 and GC Miracle Mix® Restorations using Atraumatic Restorative Treatment (ART) in Rural Settings: A Randomized Controlled Trial

Objectives: This study compared the longevity of high strength posterior glass ionomer and metal-reinforced glass ionomer using ART in rural settings within an 18-month observation period. Study Design: A nonblinded parallel design randomized controlled trial was conducted among children who attended dental outreach programs in a rural area of Southern India. Atraumatic Restorative Treatment (ART) was performed in 92 permanent posterior teeth with either high strength posterior glass ionomer or metal-reinforced glass ionomer restorations. The allocation ratio was 1:1. Restorations were evaluated at 1, 6, 12 and 18 months after placement. Results: The success rate of metal-reinforced glass ionomer restorations was 100%, 95.4%, 90.4% and 87.2% as compared to high strength posterior glass ionomer whose success rates were 100%, 93%, 85% and 61.8% at the four follow ups respectively. There was a statistically significant difference between the success rate of the two materials at the end of 18 months with the metal-reinforced glass ionomer restorations having a higher success rate (p=0.015). Conclusions : Although the clinical performance of both materials were largely similar, the metal-reinforced glass ionomer restorations had a higher success rate than the conventional GIC at the end of 18 months of follow-up.

"Setting the scene in early childhood" - an MID approach for life

This article presents a discussion paper for both consideration and implementation of Minimal Intervention Dentistry (MID) principles by the general dental practitioner. It argues that if these concepts can be adopted in early childhood by both the community and the profession, "Teeth for Life" can become a reality for all. Oral Health promoting behaviours can be nurtured and supported from infancy and developed into everyday living practice for a lifetime thereby maintaining an optimal quality of life. MID techniques have become more refined and supported by scientific research in the recent times and should be considered an essential clinical guideline for the future disease management.

Clinical wear of approximal glass ionomer restorations protected with a nanofilled self-adhesive light-cured protective coating

High viscous glass ionomer cement (GIC) has gained popularity as a restorative material; however, high wear is pointed as one of the major drawbacks of this material. Protective surface coatings were developed to protect GIC from water contamination with the additional advantage of occluding any surface cracks or porosities commonly found in this material, possibly resulting in an increased wear resistance of the restorations.

Physical property investigation of contemporary glass ionomer and resin-modified glass ionomer restorative materials

OBJECTIVES

The objective of this study was to investigate selected physical properties of nine contemporary and recently marketed glass ionomer cement (GIC) and four resin-modified glass ionomer cement (RMGI) dental restorative materials.

MATERIALS AND METHODS

Specimens (n = 12) were fabricated for fracture toughness and flexure strength using standardized, stainless steel molds. Testing was completed on a universal testing machine until failure. Knoop hardness was obtained using failed fracture toughness specimens on a microhardness tester, while both flexural modulus and flexural toughness was obtained by analysis of the flexure strength results data. Testing was completed at 1 h, 24 h, 1 week, and then at 1, 3, 6, and 12 months. Mean data was analyzed with Kruskal-Wallis and Mann-Whitney (p = 0.05).

RESULTS

Physical properties results were material dependent. Physical properties of the GIC and RMGI products were inferior at 1 h compared to that at 24 h. Some improvement in selected physical properties were noted over time, but development processes were basically concluded by 24 h. A few materials demonstrated improved physical properties over the course of the evaluation.

CONCLUSIONS

Under the conditions of this study: 1. GIC and RMGI physical property performance over time was material dependent; 2. Polyalkenoate maturation processes are essentially complete by 24 h; 3. Although differences in GIC physical properties were noted, the small magnitude of the divergences may render such to be unlikely of clinical significance; 4. Modest increases in some GIC physical properties were noted especially flexural modulus and hardness, which lends support to reports of a maturing hydrogel matrix; 5. Overall, GIC product physical properties were more stable than RMGI; 6. A similar modulus reduction at 6 months for both RMGI and GIC produced may suggest a polyalkenoate matrix change; and 7. Globally, RMGI products demonstrated higher values of flexure strength, flexural toughness, and fracture toughness than GIC materials.

CLINICAL RELEVANCE

As compared to RMGI materials, conventional glass ionomer restorative materials demonstrate more stability in physical properties.

Atraumatic restorative treatment versus conventional restorative treatment for managing dental caries

BACKGROUND

Dental caries is a sugar-dependent disease that damages tooth structure and, due to loss of mineral components, may eventually lead to cavitation. Dental caries is the most prevalent disease worldwide and is considered the most important burden of oral health. Conventional treatment methods (drill and fill) involve the use of rotary burs under local anaesthesia. The need for an electricity supply, expensive handpieces and highly trained dental health personnel may limit access to dental treatment, especially in underdeveloped regions.To overcome the limitations of conventional restorative treatment, the Atraumatic Restorative Treatment (ART) was developed, mainly for treating caries in children living in under-served areas of the world where resources and facilities such as electricity and trained manpower are limited. ART is a minimally invasive approach which involves removal of decayed tissue using hand instruments alone, usually without use of anaesthesia and electrically driven equipment, and restoration of the dental cavity with an adhesive material (glass ionomer cement (GIC), composite resins, resin-modified glass-ionomer cement (RM-GICs) and compomers).

OBJECTIVES

To assess the effects of Atraumatic Restorative Treatment (ART) compared with conventional treatment for managing dental caries lesions in the primary and permanent teeth of children and adults.

SEARCH METHODS

Cochrane Oral Health's Information Specialist searched the following databases: Cochrane Oral Health's Trials Register (to 22 February 2017), the Cochrane Central Register of Controlled Trials (CENTRAL) (the Cochrane Library, 2017, Issue 1), MEDLINE Ovid (1946 to 22 February 2017), Embase Ovid (1980 to 22 February 2017), LILACS BIREME Virtual Health Library (Latin American and Caribbean Health Science Information database; 1982 to 22 February 2017) and BBO BIREME Virtual Health Library (Bibliografia Brasileira de Odontologia; 1986 to 22 February 2017). The US National Institutes of Health Trials Registry (ClinicalTrials.gov) and the World Health Organization International Clinical Trials Registry Platform were searched for ongoing trials. No restrictions were placed on the language or date of publication when searching the electronic databases.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) with at least six months' follow-up that compared the effects of ART with a conventional restorative approach using the same or different restorative dental materials to treat caries lesions.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened search results, extracted data from included studies and assessed the risk of bias in those studies. We used standard methodological procedures expected by Cochrane to evaluate risk of bias and synthesise data. Where pooling was appropriate we conducted meta-analyses using the random-effects model. We assessed the quality of the evidence using GRADE criteria.

MAIN RESULTS

We included a total of 15 eligible studies randomising 3760 participants in this review. The age of participants across the studies ranged from 3 to 101 years, with a mean of 25.42 years. 48% of participants were male. All included studies were published between 2002 and 2016. Two of the 15 studies declared that the financial support was from companies that manufacture restorative material. Five studies were individually randomised parallel-group studies; six were cluster-randomised parallel-group studies; and four were randomised studies that used a split-mouth design. Eleven studies evaluated the effects of ART on primary teeth only, and four on permanent teeth. The follow-up period of the included studies ranged from 6 months to 36 months. We judged all studies to be at high risk of bias.For the main comparison of ART compared to conventional treatment using the same material: all but two studies used high-viscosity glass ionomer (H-GIC) as the restorative material; one study used a composite material; and one study used resin-modified glass ionomer cement (RM-GIC)).Compared to conventional treatment using H-GIC, ART may increase the risk of restoration failure in the primary dentition, over a follow-up period from 12 to 24 months (OR 1.60, 95% CI 1.13 to 2.27, five studies; 643 participants analysed; low-quality evidence). Our confidence in this effect estimate is limited due to serious concerns over risk of performance and attrition bias. For this comparison, ART may reduce pain during procedure compared with conventional treatment (MD -0.65, 95% CI -1.38 to 0.07; 40 participants analysed; low-quality evidence)Comparisons of ART to conventional treatment using composite or RM-GIC were downgraded to very low quality due to indirectness, imprecision and high risk of performance and attrition bias. Given the very low quality of the evidence from single studies, we are uncertain about the restoration failure of ART compared with conventional treatment using composite over a 24-month follow-up period (OR 1.11, 95% CI 0.54 to 2.29; one study; 57 participants) and ART using RM-GIC in the permanent teeth of older adults with root caries lesions over a six-month follow-up period (OR 2.71, 95% CI 0.94 to 7.81; one study; 64 participants).No studies reported on adverse events or costs.

AUTHORS' CONCLUSIONS

Low-quality evidence suggests that ART using H-GIC may have a higher risk of restoration failure than conventional treatment for caries lesions in primary teeth. The effects of ART using composite and RM-GIC are uncertain due to the very low quality of the evidence and we cannot rely on the findings. Most studies evaluated the effects of ART on the primary dentition.Well-designed RCTs are required that report on restoration failure at clinically meaningful time points, as well as participant-reported outcomes such as pain and discomfort. Due to the potential confounding effects from the use of different dental materials, a robust body of evidence on the effects of ART compared with conventional treatment using the same restoration material is necessary. We identified four ongoing trials that could provide further insights into this area.

Influence of acceleration setting reaction by halogen light-curing on GIC-dentin interface: Qualitative analysis by SEM

The aim of this study was to evaluate by scanning electron microscope (SEM) photomicrographs the influence of application of halogen light-curing for fastening the set reaction of high-viscosity glass ionomer cements (GIC) by assessing the material/dentin interface. Twelve human primary canines were assigned in four groups (n = 3) according to the GIC (Fuji IX, GC or Maxxion R, FGM) and application of halogen light-curing (60 sec or control-no external energy). Blocks with approximately 6 mm of height were buildup on previously pre-treated dentin surface in according to the experimental group. After storage at 37 °C, 100% humidity for 48 h, the specimens were then sectioned in slices with 1-mm thick. The slices were qualitative analyzed using SEM to evaluate possible structural changes. Two examiners independently evaluated the images in order to observe the spherical hollow spaces of each tooth. The photomicrographs revealed the presence of spherical hollow spaces in all experimental groups. However, in both groups that received halogen light-curing application, it was possible to observe that the presence of these hollow spaces decreased in size and quantity. It can be concluded that the halogen light-curing application positively decreases in size and quantity in the presence of spherical hollow spaces in GIC.

Three-dimensional biofilm properties on dental bonding agent with varying quaternary ammonium charge densities

OBJECTIVES

Tooth-restoration interfaces are the weak link with secondary caries causing restoration failure. The objectives of this study were to develop an antimicrobial bonding agent with dimethylaminododecyl methacrylate (DMAHDM), and investigate the effects of quaternary amine charge density on three-dimensional (3D) biofilms on dental resin for the first time.

METHODS

DMAHDM was synthesized and incorporated into Scotchbond Multi-Purpose bonding agent at mass fractions of 0% (control), 2.5%, 5%, 7.5% and 10%. Streptococcus mutans bacteria were inoculated on the polymerized resin and cultured for two days to form biofilms. Confocal laser scanning microscopy was used to measure biofilm thickness, live and dead biofilm volumes, and live bacteria percentage in 3D biofilm vs. distance from resin surface.

RESULTS

Charge density of the resin had a significant effect on the antibacterial efficacy (p<0.05). Biofilms on control resin had the greatest thicknesses. Biofilm thickness and live biofilm volume decreased with increasing surface charge density (p<0.05). There were significant variations in bacterial viability along the 3D biofilm thickness (p<0.05). At 2.5% and 5% DMAHDM, the bacterial inhibition was the greatest on or near the resin surface, and the killing effect decreased away from the resin surface. At 10% DMAHDM, the entire 3D biofilm was dead and the percentage of live bacteria was nearly 0% throughout the biofilm thickness.

CONCLUSIONS

Adding new antibacterial monomer DMAHDM into dental bonding agent yielded a strong antimicrobial activity, substantially decreasing the 3D biofilm thickness, live biofilm volume, and percentage of live bacteria on cross-sections through the biofilm thickness.

SIGNIFICANCE

Novel DMAHDM-containing bonding agent with capability of inhibiting 3D biofilms is promising for a wide range of dental restorative and preventive applications to inhibit biofilms at the tooth-restoration margins and prevent secondary caries.

Bilayer technique and nano-filled coating increase success of approximal ART restorations: a randomized clinical trial

BACKGROUND

The high-viscosity consistency of glass ionomer cement (GIC) may lead to its incorrect adaptation into the cavity and therefore to restoration failure.

AIM

To compare two different insertion techniques for GIC in approximal atraumatic restorative treatment (ART) restorations and two different surface protection materials.

DESIGN

Approximal caries lesion in primary molars from 208 schoolchildren was randomly assigned into four groups: G1, conventional GIC insertion protected with petroleum jelly (PJ); G2, bilayer technique protected with PJ; G3 conventional GIC insertion protected with nano-filled particles coating for GIC (NPC); G4, bilayer technique protected with NPC. Restorations were evaluated after 1, 6, 12, 18, 24, and 36 months. Kaplan-Meier survival analysis and log-rank test were performed. Cox regression analysis (α = 5%) was used to verify the influence of clinical factors.

RESULTS

Restoration survival was 52.8%. Log-rank test indicated a better survival of the bilayer technique restorations, compared to conventional restorations (P = 0.005), whereas the coated conventional restorations presented higher survival than the uncoated ones (P = 0.035). Cox regression analysis showed no influence of any clinical tested variables.

CONCLUSION

The survival rate of the approximal ART restorations is positively influenced by the bilayer technique, and the application of nano-filled coating increases the longevity of the conventional approximal ART restorations.

To Analyse the Erosive Potential of Commercially Available Drinks on Dental Enamel and Various Tooth Coloured Restorative Materials - An In-vitro Study

INTRODUCTION

With the enormous change in life style pattern of a common man through the past few decades, there has been proportional variation in the amount and frequency of consumption of drinks. An increased consumption of these drinks will concurrently increase enamel surface roughness by demineralization, resulting in hypersensitivity and elevated caries risk.

AIM

The present study was designed to evaluate the erosive potential of commercially available drinks on tooth enamel and various tooth coloured restorative materials.

MATERIALS AND METHODS

Extracted human teeth were taken and divided into four groups i.e. tooth enamel, glass ionomer cement, composite and compomer. Four commercially available drinks were chosen these were Coca -Cola, Nimbooz, Frooti and Yakult. The pH of each drink was measured. Each group was immersed in various experimental drinks for a period of 14 days. The erosive potential of each drink was measured by calculating the change in average surface roughness of these groups after the immersion protocol in various drinks. The data analysis was done by One Way Anova, Post-Hoc Bonferroni, and paired t -test.

RESULTS

Group II-GIC showed highest values for mean of change in average surface roughness and the values were statistically significant (p<0.001) with tooth enamel, composite and compomer (p=0.002). Coca-cola showed the highest erosive potential and Yakult showed the lowest, there was no statistical significant difference between the results shown by Yakult and Frooti.

CONCLUSION

Characteristics which may promote erosion of enamel and tooth coloured restorative materials were surface texture of the material and pH of the drinks.

Atraumatic Restorative Treatment compared to the Hall Technique for occluso-proximal cavities in primary molars: study protocol for a randomized controlled trial

Background

In many parts of the world, school-age children have high dental treatment needs; however, there is often low, or no, dental care provision. Although Atraumatic Restorative Treatment (ART) was developed to address this, its survival rate in occluso-proximal lesions is low. An alternative, the Hall Technique (HT) has shown better relative outcomes for occluso-proximal lesions, but has not been directly compared to ART or tested in field settings. This trial will compare ART and the HT for the most clinically- and cost-effective strategy for managing occluso-proximal lesions in primary molars, in a school setting, using low-technology and child-friendly dental techniques.

Methods/Design

This two-arm, parallel group, patient-randomized controlled, superiority trial will have treatment provided in schools. Schoolchildren (n = 124, age 6–8) with at least one occluso-proximal carious primary molar lesion will have random allocation to treatment with ART or HT. Baseline measures and outcome data will be assessed through participant report, clinical examination and parent report/questionnaires. The primary outcome is survival rate, a composite measure of absence of Minor Failures (a defect in the restoration/crown, but not interfering with tooth health) and Major Failures (signs or symptoms of irreversible pulp damage, such as dental fistula/abscess, tooth fracture or failures that cannot be repaired). Secondary outcomes are: (1) child-reported discomfort, (2) childrens’ and (3) parents’ concerns around dental appearance and (4) acceptability of treatments, (5) occlusal-vertical dimensions (OVD) changes, (6) plaque index, (7) gingival health, (8) decayed, missing, filled teeth in permanent teeth (DMFT)/decayed, missing, filled teeth in primary teeth (dmft), (9) oral health-related-quality of life, reported by children and parents/caregivers, (10) the incremental cost-effectiveness, and (11) operator effect. A trained and calibrated examiner will evaluate the treated teeth after 1 week, then 1, 6, 12, 24 and 36 months post treatment. Kaplan-Meier and Cox regression tests will be used to investigate the primary outcome. The Mann-Whitney or t test, Friedman test, paired t test or Wilcoxon test and Ordinal Logistic Regression Analysis will be used to analyze the secondary outcomes.

Discussion

The results of this trial will support decision-making by clinicians and policy-makers for managing occluso-proximal lesions in settings with constrained resources and limited dental access.

Trial registration

www.clinicaltrials.gov, NCT02569047, registered 5 October 2015.

Electronic supplementary material

The online version of this article (doi:10.1186/s13063-016-1270-z) contains supplementary material, which is available to authorized users.

Design and development of self-healing dental composites

The purpose of this project is to design and develop a clinically applicable self-healing dental composite (SHDC). The value of resin-based dental restorations could be improved by increasing their service lives. One way to improve longevity is to obturate micro-cracks that form during or after the composite hardens in the dental cavity. Toward this end, we introduce here a new type of SHDC made with contemporary dental components plus two additional ingredients: a healing powder (HP, strongtium fluoroaluminosilicate particles) and a healing liquid (HL, aqueous solutions of polyacrylic acids) that is enclosed within silica microcapsules. As micro-cracks develop, they will break the microcapsules in their propagation path, thereby releasing HL. This liquid will then react with particles of HP exposed by the crack formation, forming an insoluble reaction product that fills and seals the cracks. The key factors to achieve this self-healing of cracks are discussed. The elastic modulus of a SHDC appeared to be satisfactory. The healing process was confirmed by means of mechanical, morphological, and chemical methods. The SHDC restored micro-cracks without external intervention, thereby showing potential for increasing the service lives of dental restorations. Importantly, this SHDC contains only clinically-tested, biocompatible materials, making it readily applicable.

Caries-Preventive Effect of High-Viscosity Glass Ionomer and Resin-Based Fissure Sealants on Permanent Teeth: A Systematic Review of Clinical Trials

BACKGROUND

Glass-ionomers are traditionally regarded to be inferior to resin as fissure sealants in protecting teeth from dental caries, due to their comparatively lower retention rate. Unlike low-viscosity glass-ionomers, high-viscosity glass-ionomer cements (HVGIC) are placed as sealants by pressing the material into pits and fissures with a petroleum-jelly-coated index finger. Hence, HVGIC sealants are assumed to penetrate pits and fissures deeper, resulting in a higher material retention rate, which may increase its caries-preventive effect.

METHODS

The aim of this review was to answer the question as to whether, in patients with fully erupted permanent molar teeth, HVGIC based fissure sealants are less effective to protect against dental carious lesions in occlusal pits and fissures than resin-based fissure sealants? A systematic literature search in eight databases was conducted. Heterogeneity of accepted trials and imprecision of the established evidence were assessed. Extracted sufficiently homogenous datasets were pooled by use of a random-effects meta-analysis. Internal trial validity was evaluated. The protocol of this systematic review was registered with the International Prospective Register of Systematic Reviews (PROSPERO / Nr.: CRD42015016007).

RESULTS

Seven clinical trials were provisionally included for further review. Of these, one was excluded. Seven trial reports reporting on six trials were accepted. From these, 11 datasets were extracted and pooled in four meta-analyses. The results suggest no statistically significant differences after up to 48 months and borderline significant differences in favour of HVGIC sealants after 60 months (RR 0.29; 95% CI: 0.09-0.95; p = 0.04 / RD -0.07; 95% CI: -0.14, -0.01). The point estimates and upper confidence levels after 24, 36, 48 and 60 months of RR 1.36; RR 0.90; RR 0.62; RR 0.29 and 2.78; 1.67; 1.21; 0.95, respectively, further suggest a chronological trend in favour of HVGIC above resin-based sealants. The internal trial validity was judged to be low and the bias risk high for all trials. Imprecision of results was considered too high for clinical guidance.

CONCLUSION

It can be concluded that: (i) Inferiority claims against HVGIC in comparison to resin-based sealants as current gold-standard are not supported by the clinical evidence; (ii) The clinical evidence suggests similar caries-preventive efficacy of HVGIC and resin-based sealants after a period of 48 months in permanent molar teeth but remains challenged by high bias risk; (iii) Evidence concerning a possible superiority of HVGIC above resin-based sealants after 60 months is poor (even if the high bias risk is disregarded) due to imprecision and requires corroboration through future research.

Failure Rate of Direct High-Viscosity Glass-Ionomer Versus Hybrid Resin Composite Restorations in Posterior Permanent Teeth - a Systematic Review

Purpose

Traditionally, resin composite restorations are claimed by reviews of the dental literature as being superior to glass-ionomer fillings in terms of restoration failures in posterior permanent teeth. The aim of this systematic review is to answer the clinical question, whether conventional high-viscosity glass-ionomer restorations, in patients with single and/or multi-surface cavities in posterior permanent teeth, have indeed a higher failure rate than direct hybrid resin composite restorations.

Methods

Eight databases were searched until December 02, 2013. Trials were assessed for bias risks, in-between datasets heterogeneity and statistical sample size power. Effects sizes were computed and statistically compared. A total of 55 citations were identified through systematic literature search. From these, 46 were excluded. No trials related to high-viscosity glass-ionomers versus resin composite restorations for direct head-to-head comparison were found. Three trials related to high-viscosity glass-ionomers versus amalgam and three trials related to resin composite versus amalgam restorations could be included for adjusted indirect comparison, only.

Results

The available evidence suggests no difference in the failure rates between both types of restoration beyond the play of chance, is limited by lack of head-to-head comparisons and an insufficient number of trials, as well as by high bias and in-between-dataset heterogeneity risk. The current clinical evidence needs to be regarded as too poor in order to justify superiority claims regarding the failure rates of both restoration types. Sufficiently large-sized, parallel-group, randomised control trials with high internal validity are needed, in order to justify any clinically meaningful judgment to this topic.

Are high-viscosity glass-ionomer cements inferior to silver amalgam as restorative materials for permanent posterior teeth? A Bayesian analysis

Background

To develop a synthesis within a Bayesian probability framework of previously established evidence, in order to derive an overall conclusion about the hypothesis (H1): ‘High-viscosity glass-ionomer cements (HVGIC) are inferior to silver amalgam as (load bearing) restorative materials for permanent posterior teeth’.

Methods

Following Bayesian method, the prior Odds that H1 is true (established from past uncontrolled clinical longitudinal and laboratory trials), the Likelihood Ratio incorporating new evidence (established from recent meta-epidemiological studies and systematic reviews of controlled clinical trials), as well as the posterior hypothesis Odds in view of the new evidence, were calculated.

Results

The prior Odds that HVGICs are clinically inferior to amalgam as restorative materials in posterior permanent teeth in relation to the hypothesis that this is not so was 1.12 to 1. The Likelihood Ratio based on new evidence in favor the hypothesis was zero and the subsequent posterior Odds 0 to 1. Therefore, based on the new evidence, the Odds that HVGICs are clinically inferior to amalgam as restorative materials in posterior permanent teeth degreased from 1.12 to zero.

Conclusion

The current evidence suggests lack of support for the hypothesis that high-viscosity glass-ionomer cements are inferior to silver amalgam as restorative materials for permanent posterior teeth. Should future research to this topic uphold the current findings, a wider range of clinical benefits for both patient and care provider, beyond appropriate restoration longevity for placing HVGIC based restorations may apply.

Electronic supplementary material

The online version of this article (doi:10.1186/s12903-015-0108-5) contains supplementary material, which is available to authorized users.

Atraumatic restorative technique: case report on dental management of a patient with Moebius syndrome

BACKGROUND

Clinical challenges associated with Moebius syndrome, a rare congenital neuromuscular disorder, include orofacial anomalies like microstomia, limited mouth opening and severe gag reflex.

METHODS

This case report presents the dental management of an anxious female with Moebius syndrome. For restorations, atraumatic restorative technique (ART), using glass ionomer cement was used with hand instruments.

RESULTS

All necessary dental treatment was completed in the dental chair, thus avoiding the need for a general anaesthetic, and associated complications with airway management due to orofacial abnormalities.

CONCLUSIONS

ART is an appropriate technique for people with microstomia and/or limited mouth opening, such as those with Moebius syndrome. The application of ART can be extended to other special needs patients (people with physical and intellectual disabilities, extreme anxiety, needle phobia and the frail elderly in aged care facilities), where access or cooperation is difficult or limited.

How mobile are protons in the structure of dental glass ionomer cements?

The development of dental materials with improved properties and increased longevity can save costs and minimize discomfort for patients. Due to their good biocompatibility, glass ionomer cements are an interesting restorative option. However, these cements have limited mechanical strength to survive in the challenging oral environment. Therefore, a better understanding of the structure and hydration process of these cements can bring the necessary understanding to further developments. Neutrons and X-rays have been used to investigate the highly complex pore structure, as well as to assess the hydrogen mobility within these cements. Our findings suggest that the lower mechanical strength in glass ionomer cements results not only from the presence of pores, but also from the increased hydrogen mobility within the material. The relationship between microstructure, hydrogen mobility and strength brings insights into the material's durability, also demonstrating the need and opening the possibility for further research in these dental cements.

Minimal intervention dentistry and older patients part 2: minimally invasive operative interventions

As described in the first paper of this two part series, the expansion of our older population and the concomitant reduction in levels of edentulism will result in an increase in the number of patients presenting in general practice with complex restorative challenges. The application of the concepts of minimal intervention dentistry and minimally invasive operative techniques may offer a powerful armamentarium to the general dentist to provide ethical and conservative treatment to older patients.

CLINICAL RELEVANCE

When it is unavoidable, operative intervention should be as minimally invasive as practicable in older patients to preserve the longevity of their natural dentition.

Antibacterial activity and ion release of bonding agent containing amorphous calcium phosphate nanoparticles

OBJECTIVE

Recurrent caries at the margins is a primary reason for restoration failure. The objectives of this study were to develop bonding agent with the double benefits of antibacterial and remineralizing capabilities, to investigate the effects of NACP filler level and solution pH on Ca and P ion release from adhesive, and to examine the antibacterial and dentin bond properties.

METHODS

Nanoparticles of amorphous calcium phosphate (NACP) and a quaternary ammonium monomer (dimethylaminododecyl methacrylate, DMADDM) were synthesized. Scotchbond Multi-Purpose (SBMP) primer and adhesive served as control. DMADDM was incorporated into primer and adhesive at 5% by mass. NACP was incorporated into adhesive at filler mass fractions of 10%, 20%, 30% and 40%. A dental plaque microcosm biofilm model was used to test the antibacterial bonding agents. Calcium (Ca) and phosphate (P) ion releases from the cured adhesive samples were measured vs. filler level and solution pH of 7, 5.5 and 4.

RESULTS

Adding 5% DMADDM and 10-40% NACP into bonding agent, and water-aging for 28 days, did not affect dentin bond strength, compared to SBMP control at 1 day (p>0.1). Adding DMADDM into bonding agent substantially decreased the biofilm metabolic activity and lactic acid production. Total microorganisms, total streptococci, and mutans streptococci were greatly reduced for bonding agents containing DMADDM. Increasing NACP filler level from 10% to 40% in adhesive increased the Ca and P ion release by an order of magnitude. Decreasing solution pH from 7 to 4 increased the ion release from adhesive by 6-10 folds.

SIGNIFICANCE

Bonding agents containing antibacterial DMADDM and remineralizer NACP were formulated to have Ca and P ion release, which increased with NACP filler level from 10% to 40% in adhesive. NACP adhesive was "smart" and dramatically increased the ion release at cariogenic pH 4, when these ions would be most-needed to inhibit caries. Therefore, bonding agent containing DMADDM and NACP may be promising to inhibit biofilms and remineralize tooth lesions thereby increasing the restoration longevity.

The state-of-the-art of ART restorations

ART is less anxiety- and pain-provoking than traditional restorative treatments; administration of local anaesthesia is rarely required. Systematic reviews have provided evidence of the high level of effectiveness of high-viscosity glass-ionomer ART restoration in restoring single-surface cavities, both in primary and permanent posterior teeth, but its survival rates in restoring multiple-surface cavities in primary posterior teeth needs to be improved. Insufficient information is available regarding the survival rates of multiple-surface ART restorations in permanent teeth. Evidence from these reviews indicates no difference in the survival rates of single-surface high-viscosity glass-ionomer ART restorations and amalgam restorations in primary and permanent posterior teeth.

CLINICAL RELEVANCE

Where indicated, high-viscosity glass-ionomer ART restorations can be used alongside traditional restorations. ART provides a much more acceptable introduction to dental restorative care than the traditional 'injection, drill and fill'.

The effects of ambient temperature and mixing time of glass ionomer cement material on the survival rate of proximal ART restorations in primary molars

Objective:

Temperature fluctuations and material mixing times are likely to affect the consistency and integrity of the material mixture, and hence the restoration made out of it. The purpose of the present study was to determine the influence of the ambient temperature and the mixing time of glass ionomer cement (GIC) restorative material on the survival rate of proximal atraumatic restorative treatment (ART) restorations placed in primary molars.

Materials and Methods:

A total of 804 restorations were placed in the primary molars of 6-8-year-olds using the ART approach. The restorations were then followed for a period of 2 years and evaluated at given intervals. The data collected were analyzed using SPSS computer statistical program, and the results tested and compared using the Chi-square, Kaplan Meier survival analysis and Cox Proportional hazard statistical tests.

Results:

The cumulative survival rate of the restorations dropped from the initial 94.4% to 30.8% at the end of 2 years. The higher survival rate of the restorations was associated with the experienced operators and assistants when using the rubber dam isolation method. However, there was no statistically significant difference in the survival rate of the restorations when related to the room temperature and the mixing time of the GIC materials used in spite of the variations in the temperature recoded and the methods used in mixing the materials.

Conclusion:

The ambient temperature and mixing time of GIC did not have a significant effect on the survival of the proximal ART restorations.

Evaluation of three-dimensional biofilms on antibacterial bonding agents containing novel quaternary ammonium methacrylates

Antibacterial adhesives are promising to inhibit biofilms and secondary caries. The objectives of this study were to synthesize and incorporate quaternary ammonium methacrylates into adhesives, and investigate the alkyl chain length effects on three-dimensional biofilms adherent on adhesives for the first time. Six quaternary ammonium methacrylates with chain lengths of 3, 6, 9, 12, 16 and 18 were synthesized and incorporated into Scotchbond Multi-Purpose. Streptococcus mutans bacteria were cultured on resin to form biofilms. Confocal laser scanning microscopy was used to measure biofilm thickness, live/dead volumes and live-bacteria percentage vs. distance from resin surface. Biofilm thickness was the greatest for Scotchbond control; it decreased with increasing chain length, reaching a minimum at chain length 16. Live-biofilm volume had a similar trend. Dead-biofilm volume increased with increasing chain length. The adhesive with chain length 9 had 37% live bacteria near resin surface, but close to 100% live bacteria in the biofilm top section. For chain length 16, there were nearly 0% live bacteria throughout the three-dimensional biofilm. In conclusion, strong antibacterial activity was achieved by adding quaternary ammonium into adhesive, with biofilm thickness and live-biofilm volume decreasing as chain length was increased from 3 to 16. Antibacterial adhesives typically only inhibited bacteria close to its surface; however, adhesive with chain length 16 had mostly dead bacteria in the entire three-dimensional biofilm. Antibacterial adhesive with chain length 16 is promising to inhibit biofilms at the margins and combat secondary caries.

Clinical effectiveness of basic root canal treatment after 24 months: a randomized controlled trial

INTRODUCTION

The purpose of this study was to investigate the effectiveness of basic root canal treatment (BRT) with tactile working length determination in terms of radiographic and clinical outcome parameters compared with endodontic treatment with standard radiographic working length control.

METHODS

This was a clinical, multicenter, controlled, open-label trial to evaluate BRT effectiveness after 24 months. The primary end point was the apical extension score of the radiographic quality parameter of root canal fillings. The secondary radiographic end point was the periapical index, and the secondary clinical end point was tooth tender to percussion. The safety end point was tooth loss as a consequence of endodontic failure. Statistical analyses of binary and categoric data were calculated using cross tables and the chi-square test.

RESULTS

BRT with tactile working length determination compared with standard radiographic working length control did not significantly differ in terms of radiographic and clinical outcomes after 24 months. The apical extension of the root canal fillings and the periapical anatomic structures showed no significant differences according to radiographic analyses (P = .5). Corresponding results were found in clinical aspects of tooth tender to percussion (P = .6) and tooth loss (P = .7).

CONCLUSIONS

Tactile working length determination in BRT resulted in comparable treatment outcomes compared with standard endodontic treatment with radiographic working length control and turned out to be an accurate method in BRT.

Addition of Chlorhexidine Gluconate to a Glass Ionomer Cement: A Study on Mechanical, Physical and Antibacterial Properties

The objective of this work was to determine the effect of different concentrations of chlorhexidine digluconate (CHX) on setting time, surface hardness, maximum tensile bond strength and antibacterial activity of a glass ionomer cement (GIC). The material used as control was Ketac Molar Easymix GIC. CHX was incorporated into the GIC during its manipulation at concentrations of 0.5, 1.0 and 2.0%. Antimicrobial activity against S. mutans and L. acidophilus was evaluated by means of agar diffusion test. Tensile bond strength data were analyzed statistically using Analysis of variance and Tukey's test. Setting time, Vickers hardness and agar diffusion test were analyzed using Kruskal-Wallis and Mann-Whitney tests at a significance level of 5%. It was observed that adding CHX at concentrations of 1% and 2% increased significantly the setting time of the material (p=0.012 and p=0.003, respectively). There was no significant difference between control and 0.5% CHX groups regarding the setting time. Addition of 2% CHX decreased significantly the surface hardness in relation to the control group (p=0.009), followed by the 1% CHX group (p=0.009). The tensile bond strength of the material also decreased significantly after adding CHX at a concentration of 2% (p=0.001). Addition of CHX promoted formation of an inhibition halo in both bacterial strains for all concentrations. The results showed that the best option for clinical use of GIC with CHX is at 0.5% concentration, since antibacterial activity increased and the physical-mechanical properties remained unchanged.

Minimal intervention dentistry: part 5. Atraumatic restorative treatment (ART)--a minimum intervention and minimally invasive approach for the management of dental caries

While originally developed in response to a need to provide effective restorative and preventive treatment in underserved communities where running water and electricity might not always be available, over the past two decades, the atraumatic restorative treatment (ART) approach has become a worldwide phenomenon; used not only in some of the poorest developing countries but also in some of the most wealthy. The ART approach involves the removal of infected dentine with hand-instruments followed by the placement of a restoration where the adjacent pits and fissures are sealed simultaneously using high viscosity glass-ionomer inserted under finger pressure. Reliable results can only be obtained if the treatment protocol, as described in this article, is closely followed. ART should be considered as a therapeutic option especially in children, anxious patients and those with special needs.

Is Atraumatic restorative treatment an option for restoring occlusoproximal caries lesions in primary teeth? A systematic review and meta-analysis

BACKGROUND

Atraumatic restorative treatment (ART) has demonstrated good longevity when used for single-surface restorations, but lower success rates are reported for occlusoproximal surfaces.

AIM

This systematic review and meta-analysis aimed to verify the pooled success rate of occlusoproximal ART restorations in primary teeth considering the outcomes: longevity, pulp damage, or caries lesion progression.

DESIGN

Literature searching was carried out on the studies reporting clinical trials indexed in PubMed and in English language, comprising the outcomes. A meta-analysis was undertaken considering the results from reviewed studies.

RESULTS

An initial search resulted in 126 articles, and three of them were finally selected. The main reasons for excluding articles were the absence of control group, as amalgam, composite resin, or compomer restorations to be compared with ART (hand excavation + high-viscous GIC). The pooled estimate (odds ratio; 95% confidence interval) for ART approach success was 1.04 (0.65-1.66).

CONCLUSION

Atraumatic restorative treatment restorations performed with high-viscous GIC present similar survival/success rates to conventional approach using composite resin or amalgam for occlusoproximal restorations in primary teeth and can be suggested as a good option for occlusoproximal cavities in primary molars. In addition, further randomized controlled clinical investigations concerning occlusoproximal restorations in primary teeth are still necessary.

Suitability of ART approach for managing caries lesions in people with disability-Experts' opinion

OBJECTIVE

This study aimed to obtain the opinions of experts in Special Care Dentistry (SCD) regarding the suitability of the Atraumatic Restorative Treatment (ART) approach for the treatment of carious lesions in persons with disability.

MATERIAL AND METHODS

Thirty expert participants from around the world, joining the SCD Task Force meeting, Education Committee of the International Association of Disability and Oral Health (Antalya, Turkey, 2011), completed a questionnaire survey. Frequency distributions of variables were analysed using Chi-Square test for differences between variables.

RESULTS

All respondents reported having full or moderate knowledge of ART (23.3% and 63.3%, respectively) and 66.7% indicated that they felt the technique was useful for this population. However, only 50% of respondents used the technique regularly in their practice and five (16.7%) replied that they would never use it, even if a favourable evidence base for ART use in this population became available. The barriers to the introduction of ART to SCD are discussed and the need for training and further research highlighted.

CONCLUSIONS

Barriers to the implementation of ART in practice were placement of the restoration under difficult conditions and the dentist's pre-conception of the technique as being 'lower quality dentistry'. Experts suggested that some of these barriers might be overcome by improving the evidence base in favour of the technique, specifically in the population with disability.

Direct contra naïve-indirect comparison of clinical failure rates between high-viscosity GIC and conventional amalgam restorations: an empirical study

BACKGROUND

Naïve-indirect comparisons are comparisons between competing clinical interventions' evidence from separate (uncontrolled) trials. Direct comparisons are comparisons within randomised control trials (RCTs). The objective of this empirical study is to test the null-hypothesis that trends and performance differences inferred from naïve-indirect comparisons and from direct comparisons/RCTs regarding the failure rates of amalgam and direct high-viscosity glass-ionomer cement (HVGIC) restorations in permanent posterior teeth have similar direction and magnitude.

METHODS

A total of 896 citations were identified through systematic literature search. From these, ten and two uncontrolled clinical longitudinal studies for HVGIC and amalgam, respectively, were included for naïve-indirect comparison and could be matched with three out twenty RCTs. Summary effects sizes were computed as Odds ratios (OR; 95% Confidence intervals) and compared with those from RCTs. Trend directions were inferred from 95% Confidence interval overlaps and direction of point estimates; magnitudes of performance differences were inferred from the median point estimates (OR) with 25% and 75% percentile range, for both types of comparison. Mann-Whitney U test was applied to test for statistically significant differences between point estimates of both comparison types.

RESULTS

Trends and performance differences inferred from naïve-indirect comparison based on evidence from uncontrolled clinical longitudinal studies and from direct comparisons based on RCT evidence are not the same. The distributions of the point estimates differed significantly for both comparison types (Mann-Whitney U  =  25, n(indirect)  =  26; n(direct)  =  8; p  =  0.0013, two-tailed).

CONCLUSION

The null-hypothesis was rejected. Trends and performance differences inferred from either comparison between HVGIC and amalgam restorations failure rates in permanent posterior teeth are not the same. It is recommended that clinical practice guidance regarding HVGICs should rest on direct comparisons via RCTs and not on naïve-indirect comparisons based on uncontrolled longitudinal studies in order to avoid inflation of effect estimates.

Atraumatic restorative treatment and Carisolv use for root caries in the elderly: 2-year follow-up randomized clinical trial

OBJECTIVES

New preventive and treatment strategies are required to address the high prevalence of caries among the elderly. The main objective of this study was to analyze the effectiveness of Carisolv® gel to improve the clinical behavior of restorations obtained by atraumatic restorative treatment (ART) in root caries of elderly patients. A secondary objective was to determine the factors associated with the failure of ART restorations after a 2-year follow up.

MATERIAL AND METHODS

A randomized controlled trial with 2-year follow-up was designed for this purpose. Candidate caries lesions were randomly assigned to an ART group for root caries treatment with the conventional ART technique, filling with glass ionomer, or an ART + Carisolv® gel for the same ART plus the application of a caries solvent (Carisolv®). Evaluations were conducted at 6, 12, and 24 months.

RESULTS

A total of 81 restorations were performed, 37 in the ART group and 44 in the ART + Carisolv® gel group, with 22 and 26 restorations, respectively, surviving at the end of the 24-month follow-up. Survival rates at 24 months did not significantly differ between ART (63 %) and ART + Carisolv® gel (62 %) restorations. The best model for predicting the failure of the restorations included the number of tooth-brushings/day, the presence or not of prosthesis, the anterior or posterior location of the tooth, and the baseline plaque level.

CONCLUSION

The application of Carisolv does not modify the survival rate of ART restorations in elderly patients.

CLINICAL RELEVANCE

The use of Carisolv gel does not improve the outcomes of atraumatic restorative treatment.

The effect of GIC-brand on the survival rate of proximal-ART restorations

BACKGROUND

Laboratory studies show diverse behaviour of different brands of glass-ionomer cements (GIC).

AIM

This study investigated the clinical performance [survival rate (SR)] of three GIC brands applied to proximal atraumatic restorative treatment (ART) restorations. Additionally, the SR of the tooth was evaluated.

DESIGN

Proximal cavities of 262 primary molars were restored. The patients had been randomly allocated to two operators and three GIC brands: Fuji IX, Hi-Dense, and Maxxion R. Restorations were evaluated after 1, 6, 12, 18, 24, 30, and 36 months. Failed restorations were, if possible, repaired or replaced. Linear regression analyses were used to evaluate the effect of GIC brand, operator, and surface of restoration. Kaplan-Meier survival analysis and log-rank test were performed for both restoration survival and tooth survival (α = 5%).

RESULTS

After 3 years, 82.4% of the restorations were evaluated. The SR of the restorations was 24.4%, and there was no difference among GIC brands (log-rank test, P = 0.6). In the first 18 months, a significant operator effect and significantly higher failures in distal surfaces were found. The SR of the tooth was 81.7%.

CONCLUSIONS

The SR of proximal ART restorations was relatively low when compared with the SR of the tooth. There are no differences in the performance among the GIC brands used in the study.

A preliminary clinical trial using flowable glass-ionomer cement as a liner in proximal-ART restorations: the operator effect

Objectives: This in vivo study was carried out to assess the influence of the operator experience on the survival rate of proximal-ART restorations using a two-layer technique to insert the glass-ionomer cement (GIC). Study Design: Forty five proximal cavities in primary molars were restored in a school setting according to the ART technique. The cavities were restored by two operators with Ketac Molar Easymix, and received a flowable layer of GIC prior to a second GIC layer with a regular consistency. The operators had different clinical experiences with ART (no experience or two years of experience), but both completed a one-week training to perform the restorations and the GIC mixing in this study. Results: After a 12-month follow-up, 74% of the restorations survived; the main reason for failure was bulk fracture or total loss of the restoration.There was no operator influence (log-rank test p=0.2) Conclusion: The results encourage future well designed controlled clinical trials using the two-layer technique for insertion of GIC in proximal-ART restorations, after training the operators.

Key words:Atraumatic Restorative Treatment (ART), Glass-ionomer, proximal restorations.

Effects of dual antibacterial agents MDPB and nano-silver in primer on microcosm biofilm, cytotoxicity and dentine bond properties

OBJECTIVES

The objective of this study was to investigate the effects of dentine primer containing dual antibacterial agents, namely, 12-methacryloyloxydodecylpyridinium bromide (MDPB) and nanoparticles of silver (NAg), on dentine bond strength, dental plaque microcosm biofilm response, and fibroblast cytotoxicity for the first time.

METHODS

Scotchbond Multi-Purpose (SBMP) was used as the parent bonding agent. Four primers were tested: SBMP primer control (referred to as "P"), P+5% MDPB, P+0.05% NAg, and P+5% MDPB+0.05% NAg. Dentine shear bond strengths were measured using extracted human teeth. Biofilms from the mixed saliva of 10 donors were cultured to investigate metabolic activity, colony-forming units (CFU), and lactic acid production. Human fibroblast cytotoxicity of the four primers was tested in vitro.

RESULTS

Incorporating MDPB and NAg into primer did not reduce dentine bond strength compared to control (p>0.1). SEM revealed well-bonded adhesive-dentine interfaces with numerous resin tags. MDPB or NAg each greatly reduced biofilm viability and acid production, compared to control. Dual agents MDPB+NAg had a much stronger effect than either agent alone (p<0.05), increasing inhibition zone size and reducing metabolic activity, CFU and lactic acid by an order of magnitude, compared to control. There was no difference in cytotoxicity between commercial control and antibacterial primers (p>0.1).

CONCLUSIONS

The method of using dual agents MDPB+NAg in the primer yielded potent antibacterial properties. Hence, this method may be promising to combat residual bacteria in tooth cavity and invading bacteria at the margins. The dual agents MDPB+NAg may have wide applicability to other adhesives, composites, sealants and cements to inhibit biofilms and caries.

Novel calcium phosphate nanocomposite with caries-inhibition in a human in situ model

OBJECTIVES

Secondary caries at the restoration margins remains the main reason for failure. Although calcium phosphate (CaP) composites are promising for caries inhibition, there has been no report of CaP composite to inhibit caries in situ. The objectives of this study were to investigate the caries-inhibition effect of nanocomposite containing nanoparticles of amorphous calcium phosphate (NACP) in a human in situ model for the first time, and to determine colony-forming units (CFU) and Ca and P ion concentrations of biofilms on the composite restorations.

METHODS

NACP with a mean particle size of 116 nm were synthesized via a spray-drying technique. Two composites were fabricated: NACP nanocomposite, and control composite filled with glass particles. Twenty-five volunteers wore palatal devices containing bovine enamel slabs with cavities restored with NACP or control composite. After 14 days, the adherent biofilms were collected for analyses. Transverse microradiography determined the enamel mineral profiles at the margins, and the enamel mineral loss ΔZ was measured.

RESULTS

NACP nanocomposite released Ca and P ions and the release significantly increased at cariogenic low pH (p<0.05). Biofilms on NACP nanocomposite contained higher Ca (p=0.007) and P ions (p=0.005) than those of control (n=25). There was no significant difference in biofilm CFU between the two composites (p>0.1). Microradiographs showed typical subsurface lesions in enamel next to control composite, but much less lesion around NACP nanocomposite. Enamel mineral loss ΔZ (mean±sd; n=25) around NACP nanocomposite was 13.8±9.3 μm, much less than 33.5±19.0 μm of the control (p=0.001).

SIGNIFICANCE

Novel NACP nanocomposite substantially reduced caries formation in a human in situ model for the first time. Enamel mineral loss at the margins around NACP nanocomposite was less than half of the mineral loss around control composite. Therefore, the Ca and P ion-releasing NACP nanocomposite is promising for caries-inhibiting restorations.

Novel dental adhesives containing nanoparticles of silver and amorphous calcium phosphate

OBJECTIVES

Secondary caries is the main reason for restoration failure, and replacement of the failed restorations accounts for 50-70% of all restorations. Antibacterial adhesives could inhibit residual bacteria in tooth cavity and invading bacteria along the margins. Calcium (Ca) and phosphate (P) ion release could remineralize the lesions. The objectives of this study were to incorporate nanoparticles of silver (NAg) and nanoparticles of amorphous calcium phosphate (NACP) into adhesive for the first time, and to investigate the effects on dentin bond strength and plaque microcosm biofilms.

METHODS

Scotchbond multi-purpose adhesive was used as control. NAg were added into primer and adhesive at 0.1% by mass. NACP were mixed into adhesive at 10%, 20%, 30% and 40%. Microcosm biofilms were grown on disks with primer covering the adhesive on a composite. Biofilm metabolic activity, colony-forming units (CFU) and lactic acid were measured.

RESULTS

Human dentin shear bond strengths (n=10) ranged from 26 to 34 MPa; adding NAg and NACP into adhesive did not decrease the bond strength (p>0.1). SEM examination revealed resin tags from well-filled dentinal tubules. Numerous NACP infiltrated into the dentinal tubules. While NACP had little antibacterial effect, NAg in bonding agents greatly reduced the biofilm viability and metabolic activity, compared to the control (p<0.05). CFU for total microorganisms, total streptococci, and mutans streptococci on bonding agents with NAg were an order of magnitude less than those of the control. Lactic acid production by biofilms for groups containing NAg was 1/4 of that of the control.

SIGNIFICANCE

Dental plaque microcosm biofilm viability and acid production were greatly reduced on bonding agents containing NAg and NACP, without compromising dentin bond strength. The novel method of incorporating dual agents (remineralizing agent NACP and antibacterial agent NAg) may have wide applicability to other dental bonding systems.