Inhibition of demineralization in vitro around fluoride releasing materials

Replacement of restorations because of secondary caries is a continuing problem in restorative dentistry. This investigation assessed the capacity of fluoride-releasing restorative materials to resist caries in vitro when used in roots. Class 5 cavities were prepared in buccal and lingual surfaces of 30 extracted premolars and restored with one of three polyacid modified resin composites (F-2000, Hytac and Compoglass F), a resin modified glass-ionomer cement (Fuji II LC) a conventional glass ionomer (Ketac-Fil), and a resin composite (Z-100). After 5 weeks in an acid gel for caries-like lesion formation, the teeth were sectioned longitudinally and examined with polarized light. The results showed that restoration of caries with polyacid modified resin composites and resin modified glass ionomer cements may be of great importance in the prevention of secondary caries around the restorations in roots. Clinical Relevance Light cured fluoride-releasing restorations may inhibit caries-like lesions. Inhibition of demineralization in vitro around fluoride releasing materials.     

Fluoride release and uptake characteristics of aesthetic restorative materials

The aims of this study were firstly to investigate the fluoride-releasing characteristics of two composite resins (Tetric and Valux Plus), two polyacid-modified resin composites (Compoglass and Dyract), and conventional glass-ionomer cement (Ceramfil beta). The second aim was to assess the fluoride uptake and subsequent release from the same range of materials. Fifteen discs (6 mm diameter and 1.5 mm height) were prepared for each material. Each disc was immersed in 4 ML of deionized water within a plastic vial. The release of fluoride was measured daily at 1, 2, 3, 4, 5, 15, 30 and 60 days. After daily fluoride release was measured for 60 days, samples were refluoridated in 1000-ppm sodium fluoride (NaF) solutions (pH 6.6) for 10 min and fluoride release was measured daily for a total of 5 days. The release of fluoride from aesthetic restorative materials was measured by using specific fluoride electrode and an ionanalyser. Results were statistically analysed by two-way repeated measure ANOVA and Duncan's multiple range test. The results revealed that all fluoride-containing materials (Ceramfil beta, Compoglass, Dyract, Tetric) released fluoride initially and the release was greatest at the first day. At any time during the test period Ceramfil beta released the most and Valux Plus did not release any detectable fluoride (P < 0.01). Sample exposures to 1000 ppm NaF solution increased the 24-h fluoride release from all fluoride-containing materials. This difference lasted only 24-48 h after exposure. Ceramfil beta had a tendency to recharge not seen with the other materials (P < 0.05).     

An in vitro investigation of marginal dentine caries abutting composite resin and glass ionomer cement restorations

BACKGROUND: There are a number of studies citing the primary reason for replacing auto cure glass ionomer cements was due to recurrent caries. The purpose of this study was to use an in vitro model to measure caries at the dentine restoration interface of bonded composite resin and auto cure glass ionomer cement restorations and to measure the amount of surface degradation occurring in the restorative materials. METHODS: Specimens of auto cure glass ionomer cements (Riva Fast, Fuji IX Fast, Ketac Molar Quick and Fuji VII) and bonded composite resin restorations (Ice, SDI) were placed separately at the dentino-enamel junction of 10 recently extracted human third molar teeth, disinfected and placed into the overflow from a continuous culture of S. mutans for two weeks. Restorations were sectioned and prepared for scanning electron microscopy (SEM) and electron probe microanalysis (EPMA). Restoration tooth interfaces were photographed and the distance from the surface of the teeth to the surface of the restorations measured. EPMA of percentage weights of calcium, phosphorous and fluoride were made outwards from the restoration surface 130pm at a depth of 10 microm below the surface of the dentine. RESULTS: There were significant differences between the surface heights of composite resin, auto cure glass ionomer cements compared to teeth surfaces. Percentage weights of calcium and phosphorus levels were similar to non-demineralized dentine in the auto cure glass ionomer cement samples but there were significant reductions in mineral content of dentine adjacent to bonded composite resin restorations. Fluoride levels were mixed. CONCLUSIONS: This study shows that placing a bonded composite resin restoration into dentine affords little protection to the surrounding tooth from caries attack although insignificant degradation of the restorative surface occurs. Placing a glass ionomer cement restoration into dentine protects the surrounding tooth from caries but degradation of the restoration surface occurs.     

The weight change of various light-cured restorative materials stored in water

This study investigated weight changes of seven different light-cured composite restorative materials, one polyacid glass ionomer compomer, and one light-cured glass-ionomer cement following short-term and long-term storage in water. Two packable composites, three universal (hybrid) composites, one microglass composite, one polyacid glass ionomer resin composite (compomer), one microhybrid low-viscosity (flowable) composite, and one light cured glass ionomer composite cement were evaluated in this study. The weight changes of these specimens were measured daily (short-term storage), and they were measured after six weeks (long-term storage) using an electronic analytical balance. A significant difference was found in Ionoliner, Dyract AP, Opticor flow, Charisma, and Solitare 2, but no significant difference was found in the others (Filtek Z 250, Filtek P60, TPH Spectrum, and Valux Plus). Weight change showed a tendency to increase with the time of water storage. The greatest weight change occurred in light-cured glass ionomer composite cement (Ionoliner), which is followed in order by the weight changes in Dyract AP, Opticor Flow, Charisma, Solitare 2, Filtek Z250, Filtek P60, TPH Spectrum; Valux Plus had the least amount of change.     

A clinical comparison of glass ionomer,resin-modified glass ionomer and resin composite restorations in the treatment of cervical caries in xerostomic head and neck radiation patients

Controversy exists as to whether there is less secondary caries at the margins of glass ionomer restorations compared with other materials that do not release fluoride. This study examined the incidence of secondary caries for three types of restorative materials in Class V restorations in xerostomic patients. The study group consisted of 45 high caries-risk adult patients who had undergone head and neck irradiation for the treatment of cancer. All were substantially xerostomic and in need of at least three restorations in the same arch. Every patient received a restoration with each of the test materials, a conventional glass ionomer (GI), a resin modified glass ionomer (RMGI) and a resin composite (C). Patients were instructed in the daily use of a neutral pH sodium fluoride gel in custom trays. Recall appointments were made at 6, 12, 18 and 24 months, and the restorations were examined for material loss, marginal integrity and recurrent caries at the restoration margin. Fluoride compliance was determined at each recall period and recorded as the percentage of recommended use during that interval. Patients were categorized at the end of the study as fluoride non-users if their average compliance was 50% or less. Those with greater than 50% compliance were categorized as fluoride users. In the latter group, no recurrent caries was found for any of the restorations, whereas a material-dependent incidence of recurrent caries was found in the fluoride non-user group. None of the GI, one RMGI and eight C restorations failed due to recurrent caries. For the fluoride non-user patients, Fishers exact test (p=0.05) showed no statistical difference between GI and RMGI but statistical differences were found among those materials and resin composite at each recall period. Recurrent caries reductions for GI and RMGI relative to C were greater than 80% in xerostomic patients not using topical fluoride supplementation.     

A clinical evaluation of the restoration of root surface caries

Root surface caries is of growing importance because its prevalence increases with age, and the population of the United States is growing older while edentulism and tooth loss rates have declined. Few clinical studies have evaluated materials used for the restoration of active root caries lesions. This study evaluated a Type II glass ionomer cement and a microfilled composite resin, both placed in preparations without mechanical retention or acid etching of enamel, in the restoration of root caries.
Fifty adult volunteers with active root caries received one or both materials with the material chosen randomly. Patients were recalled after 24 months to evaluate restorations for retention, additional caries, marginal integrity, and overall clinical acceptability. Seventy-seven restorations were available for re-evaluation.
Forty-five percent of the glass ionomer and 73% of the composite restorations were clinically acceptable after 24 months. Of the glass ionomers, 39% were fully retained compared with 73% of composite restorations. Among those partially or fully retained, 25% of the glass ionomer restorations had minimal loss of marginal integrity and 30% had extensive loss while 53% and 9% of composite restorations had minimal and extensive loss, respectively. Most restorations were clinically unacceptable because of restorative material loss.
Substantial numbers of glass ionomer cement and composite resin restorations were lost. This may be the result of difficulties in maintaining isolation and obtaining a proper gingival seal. Thus, routine use of mechanical retention is still highly recommended to reduce the loss of restorative material.     

Longevity of new hybrid restorative materials in class III cavities

The aim of this study was to evaluate the durability of two new tooth-colored restorative materials, a polyacid-modified resin composite (compomer) and a resin-modified glass ionomer cement. In an intra-individual comparison with a resin composite, the materials were studied during a 5-yr period. In 50 patients, 154 large class III restorations were placed. Most patients received one of each of the three materials. The restorations were evaluated by modified United States Public Health Service (USPHS) criteria. Of the 144 restorations evaluated, 15 were found unacceptable. No significant differences were seen between the materials concerning recurrent caries incidence. The resin composite showed a significantly better color match. No difference was found between resin composite fillings in enamel- or total-etched cavities. Significantly higher surface roughness was found in the aged resin-modified glass ionomer cement restorations. Fracture of the incisal enamel corner was observed adjacent to 10 restorations. None of the three total-etch techniques resulted in postoperative sensitivity or loss of vitality. All the restorative techniques showed a low failure rate during the 5-yr follow-up.     

The two-year clinical performance of esthetic restorative materials in noncarious cervical lesions

BACKGROUND: Materials used in restoration of cervical lesions include resin-modified glass ionomer cements, polyacid-modified resin-based composites and resin-based composites. In this study, the authors evaluated the clinical performance of these materials over a two-year period. METHODS: Thirty patients were enrolled in this study. The authors placed in these patients 130 restorations, 24 of which were Vitremer (3M Dental Products, St. Paul, Minn.), 38 were F2000 Compomer (3M Dental Products), 46 were Dyract AP (Dentsply DeTrey, Konstanz, Germany) and 22 were Valux Plus (3M Dental Products). Enamel margins were not beveled, and no mechanical retention was placed. Two independent, calibrated examiners evaluated the restorations baseline and at one and two years after placement using modified U.S. Public Health Service criteria. RESULTS: Retention rates at the end of two years were 100 percent for Vitremer, 67 percent for F2000 Compomer, 68 percent for Dyract AP and 70 percent for Valux Plus. The retention rate of Vitremer was significantly higher than that of the others (P < .05). In other categories, however, Valux Plus had the most favorable performance (P < .05). No secondary caries was detected around any restoration. CONCLUSION: Vitremer, with its high retention rate, seems to be the most appropriate material for restoration of noncarious cervical lesions, though it does not have the esthetic properties of resin-based composites. All materials used in this study were in need of improvements. CLINICAL IMPLICATIONS: Resin-modified glass ionomer cement, polyacid-modified resin-based composite and resin-based composite behaved differently in the restoration of noncarious cervical lesions. Therefore, clinicians should take factors such as esthetic needs and localization into account in selecting materials for such restorations.     

Restorative service patterns in Australia: amalgam, composite resin and glass ionomer restorations

AIM: To examine the provision of amalgam, composite resin and glass ionomer restorations, and to assess whether these main restorative services varied by patient, visit and oral health characteristics. DESIGN: A cross-sectional survey incorporating a log of service items provided on a typical day. SETTING: Australian private general practice. METHODS: Data on services and patients were collected by a mailed survey from a random sample of dentists from each State/Territory in Australia in 1998-99 with a response rate of 71%. MAIN OUTCOME MEASURES: Rates per visit of amalgam, composite resin and glass ionomer restorations among dentate adults who had received a restoration. RESULTS: Analysis showed older patients had lower amalgam rates but higher glass ionomer rates, composite resin rates were lower at emergency visits, capital city patients had higher amalgam rates but lower composite resin rates, patients with decayed teeth had higher amalgam and composite resin rates, and use of restorative materials varied by clinical problem. CONCLUSIONS: Despite widespread use of alternative materials, amalgam rates remained high in circumstances such as replacement restorations and restorations involving more than one surface. Other restorative materials also had specific applications. Both amalgam and composite resins were provided at higher rates to patients with active caries but composite resins were also used at higher rates for aesthetic problems. Glass ionomer restorations were used at higher rates for initial and one-surface restorations, and for conditions such as root caries and dentinal sensitivity.     

In vitro caries-inhibitory properties of a silver cermet

Recurrent caries is one of the primary causes of failure of dental restorations. One method for reducing the frequency and severity of this problem is the use of fluoride-releasing restorative materials. The glass-ionomer cements are a type of fluoride-releasing material. They have been used extensively in recent years for a variety of clinical applications. However, in comparison with other restorative materials such as amalgam and composite resins, glass ionomers have relatively poor physical properties. Sintering of silver particles to glass-ionomer powder is a means of improving these physical properties. The sintered material is called a silver-glass ionomer or silver cermet. This study examined the in vitro caries-inhibitory potential of a silver cement by means of two methods. First, long-term fluoride release was measured. Second, an artificial caries system was used for evaluation of caries inhibition by cerment restorations in extracted teeth. In comparison with a standard glass-ionomer restorative material, fluoride release from the cermet material was significantly less throughout a 12-month period. The results from the artificial caries system indicated that this decreased fluoride release corresponded with a lesser degree of caries inhibition. Lesions around cermet restorations in both enamel and root surfaces were significantly more severe than those around conventional glass-ionomer restorations. However, in comparison with amalgam and composite resin restorations, the cermet did have some cariostatic activity.     

Clinical evaluation of three restorative materials applied in a minimal intervention caries treatment approach

OBJECTIVES: This paper reports on a longitudinal evaluation of three materials (glass ionomer, zinc oxide-eugenol cement, and composite) employed in a minimal restorative intervention approach of 81 high caries-active pregnant women selected for a preventive oral health program in Brazil. The aim of the study was to evaluate the clinical behavior of the glass ionomer cement, currently indicated in programs for control of carious lesions. METHODS: The patients were randomly divided into two groups. Both groups were engaged in an oral health promotion approach. In Group 1, 417 glass ionomer restorations were placed in 43 individuals, involving all types and sizes of cavities. In the second group, 213 posterior zinc oxide-eugenol (ZOE) restorations and 127 anterior composite restorations were placed in 38 patients. Minimal cavity preparations were made, in which only soft or infected dentin was removed, on the basis of clinical judgment. RESULTS: After two years, the restorations were clinically evaluated by two examiners for marginal integrity, amount of wear, presence of fracture, carious lesions, and lost restorations. Statistical analysis (chi-square test) identified statistically significant difference between glass ionomer and ZOE (90.6% vs 9.2%). Comparing glass ionomer and composite, similar survival rates were observed. The success rate observed for the glass ionomer cement ranged from 77.1 percent to 92.5 percent, depending on the type and size of cavity in which it was applied. Four teeth restored with glass ionomer cement and one tooth restored with composite showed caries signs. Regarding the ZOE restorations, caries was always associated with other causes of failure such as excessive wear, restoration loss, or marginal defects, with no possibility of separate evaluation. Despite the preventive and therapeutic measurements employed, a mean increase of 2.15 new surfaces with cavities was observed in Group 1, as well as 2.83 surfaces presenting the same status in Group 2. CONCLUSIONS: This study demonstrated that highly viscous glass ionomer cement applied in a minimal intervention approach provided high-quality preventive and restorative care after two years to a population at high risk for caries. The composite was employed in cavities exposed to lower stress, such as in the anterior teeth, and its behavior was comparable to that of the glass ionomer cement. The reinforced ZOE presented a high failure rate, thus contraindicating its use for such purpose.     

In vitro evaluation of the cariostatic action of esthetic restorative materials in bovine teeth under severe cariogenic challenge

Considering that caries around restorations is a serious problem in dentistry, and some restorative materials with fluoride may be important in inhibiting these lesions, this research is aimed at performing an in vitro evaluation of the cariostatic action of some esthetic restorative materials. Standardized cavities were prepared in the center of either intact blocks of bovine enamel or with bovine teeth containing early artificial carious lesions. The specimens were restored with a high viscosity glass ionomer cement (Molar Ketac), a resin-modified glass ionomer cement (Vitremer), a polyacid-modified resin composite (Dyract AP) and a conventional resin composite (Z-250). In addition to the restored specimens, four corresponding control groups were evaluated. All groups, except for two control groups, were subjected to a demineralization/remineralization cycling model for 14 days, simulating a situation of severe cariogenic challenge. The blocks were then longitudinally sectioned through the restorations. Mineral loss was evaluated in these specimens using the Knoop microhardness profiles in longitudinal sections at three different distances of the cavities and at eight distinct depths in relation to the external enamel surface. Statistical analysis of the results showed significant differences (p < 0.05) among the groups, although none of the study materials completely inhibited creation of the lesions. Vitremer demonstrated the best cariostatic action in intact bovine enamel. Ketac Molar, in intact or demineralized enamel, and Vitremer, in demineralized enamel, presented intermediate cariostatic potential. Z-250 and Dyract AP did not demonstrate any cariostatic effect. The data suggests that glass ionomer cements demonstrated better cariostatic action compared to the other restorative materials.     

Artificial caries formation around fluoride-releasing restorations in roots

Secondary caries is one of the most important factors leading to replacement of dental restorations. This investigation assessed the capacity of fluoride-releasing restorative materials to resist caries in vitro when used in roots. Class 5 cavities were prepared in the buccal and lingual surfaces of 30 extracted premolars. The six materials used were: glass–ionomer cement (Fuji^®), glass–ionomer cement with silver particles added (Ketac-silver^®), fluoride-containing composite resin (Tetric^®), composite resin (Silux plus^®), fluoride-containing amalgam (Fluor-Alloy^®) and high-copper amalgam (Dispersalloy^®). After 5 weeks in an acid gel for caries-like lesion formation, the teeth were sectioned longitudinally and examined with polarized light. The results showed that repair with glass–ionomer materials of a carious lesion may be of great importance in the prevention of secondary caries around the restorations in roots.     

Posterior resin composite restorations with or without resin‐modified,glass‐ionomer cement lining: a 1‐year randomized,clinical trial

Aim: To investigate the effect of resin‐modified, glass‐ionomer cement lining on the quality of posterior resin composite restorations, bonded with a two‐step, total‐etch or self‐etching adhesive, at 1 year. Methods: Patients with 1–4 moderate‐to‐deep, primary occlusal caries in molars were informed and recruited. A total of 110 composite restorations were placed in 75 participants, with one of four restorative procedures: (a) bonded with a total‐etch adhesive (Single Bond 2); (b) lined with glass‐ionomer cement (Fuji Lining LC), and then bonded with total‐etch adhesive; (c) bonded with a self‐etching adhesive (Clearfil SE Bond); and (d) lined with glass‐ionomer cement, and then bonded with self‐etching adhesive. Results: At 1 year, 57 patients (86 restorations) attended the recall. Each of the restorations was evaluated and scored from 1 (clinically excellent) to 5 (clinically poor) using the following criteria: (a) patient satisfaction; (b) fracture and retention; (c) marginal adaptation; (d) recurrent caries; and (e) post‐operative sensitivity. At 1 year, the qualities of the restorations were not significantly affected by the placement of glass‐ionomer cement lining, regardless of the adhesive used (P > 0.05). Most of the restorations were scored 1 for all criteria. Conclusions: The benefit of placing a glass‐ionomer cement liner in resin composite restoration is questionable.     

Streptococcus mutans-induced secondary caries adjacent to glass ionomer cement, composite resin and amalgam restorations in vitro

The aim of this study was to define, in vitro, the potential to inhibit secondary caries of restorative materials currently used in dental practice. Standard cavities were prepared on the buccal and lingual surfaces of fifty extracted human third molars. The teeth were randomly divided into five groups, each one restored with one of the following materials: glass ionomer cement (GIC); amalgam; light-cured composite resin; ion-releasing composite; and light-cured, fluoride-containing composite resin. The teeth were thermocycled, sterilized with gamma irradiation, exposed to a cariogenic challenge using a bacterial system using Streptococcus mutans, and then prepared for microscopic observation. The following parameters were measured in each lesion formed: extension, depth, and caries inhibition area. The outer lesions developed showed an intact surface layer and had a rectangular shape. Wall lesions were not observed inside the cavities. After Analysis of Variance and Component of Variance Models Analysis, it was observed that the GIC group had the smallest lesions and the greatest number of caries inhibition areas. The lesions developed around Amalgam and Ariston pHc restorations had an intermediate size and the largest lesions were observed around Z-100 and Heliomolar restorations. It may be concluded that the restorative materials GIC, amalgam and ion-releasing composites may reduce secondary caries formation.     

Hardness and in vitro wear of a novel ceramic restorative cement

The aim of the present work was to compare a new ceramic restorative cement for posterior restorations, DoxaDent, with other types of tooth-colored materials for direct use as regards hardness and in vitro wear. Four hybrid resin composites, one polyacid-modified resin composite, one resin-modified glass ionomer cement, one conventional glass ionomer cement, one zinc phosphate cement, an experimental version as well as the marketed version of the ceramic restorative cement, were investigated. Hardness of the materials was tested with the Wallace indentation tester and wear was tested with the ACTA wear machine. All tests were carried out on 2-wk-old specimens. DoxaDent was as hard as the zinc phosphate cement and the hardest resin composite. The ceramic restorative cement wore significantly more than the resin composites, the same as the zinc phosphate cement, and less than the glass ionomer cements. No correlation between hardness and wear was found. It can be concluded that the ceramic restorative cement is a rather hard material but with a relatively low wear resistance.     

Micro‐computed tomography assessment of root dentin around fluoride‐releasing restorations after demineralization/remineralization

Using micro‐computed tomography (micro‐CT), this study assessed the inhibitory effect of three different types of restorations on root‐caries formation under a cariogenic challenge. Bovine‐root dentin blocks with a cylindrical cavity were divided into three restoration groups: a fluoride‐free self‐etch adhesive and a resin composite (SE‐ES); a self‐etch adhesive and a resin composite with multi‐ion release (FL‐BF); and a glass ionomer cement (Fuji‐VII). After the restorative procedures, the specimens were stored in artificial saliva for 1 d, then subjected to a demineralization solution for 4 d and a remineralization solution for 28 d. Mineral density and mean mineral loss of dentin around the restorations were measured using micro‐CT. The mean mineral loss values of dentin around the restorations were highest among SE‐ES restorations and lowest among Fuji‐VII restorations. Fuji‐VII showed the highest mineral density and the lowest mineral loss after 28 d of remineralization. The observations made by scanning electron microscopy demonstrated that Fuji‐VII created the smallest outer lesion followed by FL‐BF and SE‐ES. Fuji‐VII has a larger inhibitory effect on root caries around the restorations and enhances remineralization more effectively than either FL‐BF or SE‐ES. Multi‐ion and fluoride release from the restorative materials may be beneficial for inhibition of root‐dentin caries around the restorations.     

Flexural strength and modulus of a novel ceramic restorative cement intended for posterior restorations as determined by a three-point bending test

The aim of this study was to compare a new restorative cement intended for posterior restorations, Doxadent, with other types of tooth-colored materials as regards flexural strength and flexural modulus. The new restorative material consists mainly of calcium aluminate. Four hybrid resin composites, one polyacid-modified resin composite, one resin-modified glass ionomer cement, one conventional glass ionomer cement, one zinc phosphate cement, and an experimental version as well as the marketed version of Doxadent were investigated. Flexural strength and flexural modulus were tested according to ISO standard 4049 and determined after 1 d, 1 week, and 2 weeks. Together with the zinc phosphate cement, Doxadent had the lowest flexural strengths (13-22 MPa). The strongest materials were the resin composites and the polyacid-modified resin composite (83-136 MPa). The highest flexural modulus was found for Doxadent (17-19 GPa). The flexural strength of Doxadent decreased significantly from 1 week to 2 weeks, while flexural modulus remained unchanged. The other materials reacted in different ways to prolonged water storage. It can be concluded that the restorative cement Doxadent had significantly lower flexural strength and significantly higher flexural modulus than today's materials used for direct posterior restorations.     

Direct placement restorative materials for use in posterior teeth: the current options

The purpose of this paper is to provide guidelines to assist in the selection of dental materials for restoring posterior teeth in adolescents. Currently, amalgam is still the best plastic restorative material for some Class I cavities, and for Class II cavities and all multi-surface restorations. Tooth-coloured materials are preferred by some patients and dentists, however these alternatives are more technique sensitive than amalgam. Composite resin is the most common direct placement alternative to dental amalgam, providing patients with relatively low cost, tooth-coloured restorations. However, composite resins have limited indication, their placement is more time-consuming than for amalgam, cost-benefit considerations are a concern, difficulty in obtaining a marginal seal persists and there are few long-term studies published in the peer reviewed scientific literature. The literature currently supports the use of composite resin for the restoration of a limited range of Class I and Class II cavities. Composite resin restorations are not recommended for MOD or other multi-surface restorations. In selected clinical situations, fissure sealants, preventive resin restorations and glass ionomer cement are also appropriate materials to use to restore posterior teeth. Fissure sealants, when properly maintained, can play a significant role in the prevention and control of dental caries in pits and fissures in primary and permanent teeth. Preventive resin restorations should be placed to restore deep pits and fissures with incipient caries and/or developmental defects in primary and permanent teeth. Glass ionomer cement may be used for restoring Class V cavities where appearance is not the primary concern, for conservative Class III cavities, and as a provisional restorative material. It is not recommended for Class II or IV restorations.     

Early detection of secondary caries using quantitative,light-induced fluorescence

The authors hypothesize that the arrestment and remineralization of these lesions could be improved if secondary caries could be detected and monitored at earlier stages. Traditional diagnostic techniques detect secondary caries when it is relatively advanced and when significant tissue has been lost. This in vitro study evaluated the Quantitative Light-induced Fluorescence (QLF) system for detecting and monitoring demineralization surrounding tooth-colored restorations. This investigation was divided into three studies. The first study evaluated QLF for the detection and measurement of chemically induced lesions surrounding resin composite restorations. The second study evaluated QLF for the detection of demineralization around different tooth-colored restorations (glass ionomer, resin composite, compomer and smart material) created in a microbial caries model. Finally, the third study tested whether QLF was effective at detecting early wall lesions adjacent to resin composite restorations. Data from Study 1 demonstrated the potential for QLF to detect very early secondary caries and to distinguish between the different stages of early demineralization. Study 2 confirmed the potential for QLF to detect early secondary caries created by cariogenic bacteria and concluded that the four types of materials differed in their ability to prevent secondary caries in this model, with the glass ionomer being the most effective and the non-fluoride releasing composite performing the worst, which allowed for the development of larger lesions. The results of Study 3 suggest a potential application of the QLF system to detect early wall lesions. Data from this investigation strongly suggest that QLF is a potentially viable technology to detect and monitor early secondary caries.