Evaluation of fissure sealant applied to topical fluoride treated teeth

Fissure sealant is an important tool in the prevention of dental caries. This study evaluated the effect of treating the enamel with topical fluoride gel prior to acid etching on sealant retention clinically (Part I) and in vitro (Part II). In part I a split mouth design using contralateral first permanent molars was conducted. Seventy (35 pairs) molars were sealed. Fissure sealant was applied on one side of the mouth (control group) and the contralateral tooth received acidulated phosphate fluoride gel (test group) prior to acid etching. The sealant was evaluated after 6 and 12 months and scored as intact, partially lost or completely missing. In part II, the shear bond strength between sealant and buccal enamel of extracted permanent molars without or with topical fluoride treatment was evaluated. Results showed no statistically significant differences between the test and control groups either clinically or in vitro. It is concluded that topical fluoride application prior to acid etching does not have a deleterious effect on sealant retention. However, further investigations should be conducted using different types of fluoride before altering the traditional practices.

Microtensile bond strength to ground enamel by glass-ionomers, resin-modified glass-ionomers, and resin composites used as pit and fissure sealants

OBJECTIVES

To measure the microtensile bond strength to ground enamel of different types of materials used as pit and fissure sealants in combination with different substrate conditioners.

METHODS

From 40 sound extracted molars, eight groups of five teeth were randomly formed. The experimental groups were: (1) (C) 37% phosphoric acid/ClinPro Sealant (3M ESPE); (2) (G) 37% phosphoric acid/Guardian Seal (Kerr); (3) (E/TF) 37% phosphoric acid/Excite/Tetric Flow (Ivoclar-Vivadent) (4) (OS/UF) 37% phosphoric acid/One Step (Bisco)/UniFil Flow (GC); (5) (OS/AE) 37% phosphoric acid/One Step/AEliteflo (Bisco); (6) (UB/UF) UniFil Bond/UniFil Flow (GC); (7) (CC/FVII) GC Cavity Conditioner/Fuji VII (GC); (8) (CC/FII) GC Cavity Conditioner/Fuji II LC Improved (GC). On the buccal of each tooth, a 5mm high build-up was created by incrementally adding layers of the sealing material on the conditioned enamel. By serially cutting the built-up tooth, multiple beam-shaped specimens about 1mm x 1mm in cross section were obtained, and loaded in tensile (0.5 mm/min) until failure occurred.

RESULTS

The bond strengths measured in MPa were: (C) 20.41+/-11.79; (G) 16.02+/-7.99; (E/TF) 24.06+/-9.67; OS/UF 15.63+/-9.00; (OS/AE) 9.31+/-6.05; (UB/UF) 4.96+/-3.46; (CC/FVII) 1.70+/-2.19; (CC/FII) 2.19+/-1.44.

CONCLUSIONS

The conventional and the resin-modified glass ionomers measured bond strengths significantly lower than those of any resin-based materials. Failure frequently occurred cohesively within the cement. Flowable composites in combination with phosphoric acid and a total-etch adhesive performed similarly to resin-based materials specifically conceived for sealings, such as ClinPro Sealant and Guardian Seal. The bond achieved by resin composite when treating enamel with the self-etching primer used in this study (UniFil Bond) was significantly lower than that developed when the substrate was etched with 37% phosphoric acid.

Evaluation of residual monomer elimination methods in three different fissure sealants in vitro

The aim of this study was to determine the concentration of residual monomers and to evaluate the effectiveness of elimination methods of residual monomers in three different fissure sealant materials (Helioseal F, Filtek Flow and EXM-510). The sealant materials were divided into four subgroups because of the treatment methods used; one control group and three experimental groups (cotton roll, rubber cup and prophylaxis paste in cup). High performance liquid chromatography was used to determine the concentrations of residual monomers. Results of the study showed that residual Bis-glycidyl dimethacrylate elution was the highest in Helioseal F and the lowest in Filtek Flow with the three methods tested. For triethleneglycol dimethacrylate, EXM-510 eluted the highest residual monomer. It was also found that although the three tested methods were insufficient for removing all of the residual monomers and rubbing with cotton rolls was more effective than other two methods.

Clinical Study on the Effect of Professional Cleaning of Occlusal Tooth Surfaces on Laser Fluorescence Measurements

Manufacturer's advice is to professionally clean teeth before using a laser fluorescence (LF) device in order to avoid false-positive diagnoses. Professional cleaning is not included in routine dental check-ups in children in Finland because it is time-consuming. The aim of our present study was to evaluate the effect of professional cleaning of teeth on LF in children. A total of 642 occlusal surfaces in permanent molars and premolars in 9- to 16-year-olds (n = 46) were first examined visually. After that the first measurements with LF were made without cleaning the teeth. At the same appointment the second measurements were carried out after professional cleaning using a soft rubber cup and either polishing paste or plain water spray. The differences in LF of uncleaned and cleaned teeth were determined separately for teeth with a visual score of 0 (sound) and > 0. In premolars cleaning had no significant effect on LF. In molars, the values increased when the teeth were cleaned, the difference of the measurements being statistically significant in molars with visual score > 0 cleaned with plain water spray. For molars that were cleaned with paste, the differences were not statistically significant. Sealants did not modify the effect of cleaning. As a conclusion cleaning with a rotating instrument and water spray before LF measurements is recommended in teeth with visible plaque. Also in clean teeth, cleaning is advisable in cases where LF readings approach threshold level for operative intervention. The finding that uncleaned teeth gave lower values than cleaned teeth is opposite to what has been suggested.

Pit and fissure sealants: results at five and ten years

AIM

This was to evaluate the efficacy of pit and fissure sealant (FS) using two different application techniques for caries prevention assessed at five and ten years.

METHODS

The study was conducted using Delton(R) pit and fissures sealant applied with either rubber dam (RD) (Group A: 50 children, 200 first permanent molars, 120 second permanent molars) or cotton wool rolls (CR) (Group B: 50 children, 200 first permanent molars, 112 second permanent molars). At five and ten years FS were evaluated for retention, loss and incidence of occlusal and proximal carious lesions recorded.

STATISTICS

The data were analysed with the Chi- square test comparing the results obtained for first permanent molars and second permanent molars at five and ten years.

RESULTS

There was no statistical difference between results in the two groups (p< or =0.05). The highest retention rate, 81.7%, was found for second permanent molars sealed under RD at the five year assessment. The lowest, 64.3% also for second molars sealed under CR humidity control at ten years.

CONCLUSIONS

Pit and fissure sealants are a valid preventive approach that can be applied with similar results with rubber dam or cotton rolls.

Use of a self-etching adhesive on previously etched intact enamel and its effect on sealant microleakage and tag formation

AIM

This study verified the effects of a self-etching adhesive applied on pre-etched fissures (phosphoric acid 35%) on microleakage, penetration ability and tag formation of a fissure sealant.

METHODS

80 extracted sound human molar teeth were randomly divided into four groups and bisected in two equal parts, forming two subgroups, denominated A and B. Groups 1 and 2 were etched with phosphoric acid for 60 and 40s, respectively. Groups 3 and 4 were etched with phosphoric acid (40 and 20s, respectively) and afterwards treated with Xeno III (20s). All the procedures on sealant placement were performed under 90+/-2% relative humidity. The subgroups A and B were submitted to 1000 and 5000 thermal cycles, respectively. The samples were examined by light microscopy and by confocal laser scanning microscopy (CLSM) after sectioning. Microleakage, penetration ability, fissure type, tag formation quality and tag length were measured.

RESULTS

Etching with phosphoric acid for 60s showed statistically significantly lower microleakage when compared to the other groups and significantly better tag formation quality and longer tags compared to 20s H(3)PO(4) plus Xeno III. Fissure type and number of thermal cycles were not significant factors on sealant microleakage. The penetration ability of the sealant in the fissure systems was not influenced by the treatment regimes. Shallow fissures showed a significant better tag formation than deep fissures. No significant difference in the prevalence of fissure types was seen among the groups.

CONCLUSION

Etching fissures with phosphoric acid for 60s showed best results. The additional use of Xeno III did not improve fissure sealing under the conditions of this study.

Fluoride-releasing capacity and cariostatic effect provided by sealants

This study evaluated the effect of sealants on enamel demineralization, focusing on physical protection of the sealed enamel and fluoride protection of the adjacent unsealed enamel. Occlusal fissures with areas measuring 12 mm2 were delimited in 48 extracted molars, randomly divided into 4 groups (n =12): 1) no sealing; 2) sealing with a resin-modified glass-ionomer (Vitremer, 3M ESPE); 3) sealing with a fluoride-releasing composite sealant (Clinpro Sealant, 3M ESPE); and 4) sealing with a non-fluoridated composite sealant (Concise, 3M ESPE). A 4-mm2 window was outlined on the buccal enamel for analysis of fluoride uptake. Following treatment, groups 2, 3 and 4 were subjected to 5-days of pH-cycling, while group 1 was kept in a moist environment at 37 degrees C. Fluoride uptake was assessed by dental biopsy, and the amount of fluoride released to the cycling solutions was determined by ion analysis. Enamel demineralization around the sealants was evaluated by cross-sectional micro-hardness analysis. Group 2 showed higher levels of fluoride release (P < 0.01) and uptake by enamel (P < 0.05), and lower levels of demineralization (P < 0.05) than groups 3 and 4. Group 3 exhibited reduced demineralization on unsealed enamel and provided fluoride uptake in a distant enamel area, while group 4 did not.

Curing kinetics of a photo-polymerized dental sealant

PURPOSE

To evaluate the effect of using a variety of light-curing sources on the extent (monomer conversion) and rate of cure of a light-cured dental sealant.

METHODS

Infrared spectroscopy recorded real-time polymerization of a self-cured and a light-cured sealant when the latter was exposed using manufacturer's recommendations [quartz-tungsten-halogen (QTH)] for 20 seconds as well as to other light sources: high intensity QTH, plasma arc light (PAC), and second-generation blue light emitting diode (LED) units. Specimens were heated to 37 degrees C and the degree and rate of conversion were recorded at each second for 300 seconds. Conversion extent and rate were compared among light units as well as to the self-curing product. Five replications for each test condition were performed.

RESULTS

After 300 seconds, self-curing product conversion was equivalent to all light-exposed specimens. The self-cured rate of cure was significantly lower than all light-cured scenarios. The high intensity QTH light provided equivalent conversion as conventional 20-second QTH exposure (control) in only 10 seconds. The PAC light required similar exposure time as conventional QTH treatment. Second-generation blue LED units reached conversion similar to control in only 10 seconds, while one light required only 5 seconds' exposure.

Microleakage and sealant penetration using a vibrating probe

PURPOSE

To evaluate the effect of a vibrating probe on sealant penetration into pits and fissures.

METHODS

Thirty-six extracted human third molars were used. The occlusal surface of each molar was cleaned with a rubber cup and pumice slurry. Scotchbond Etchant (35% phosphoric acid gel) was applied to the occlusal fissures of each molar for 20 seconds. Fissures were then sealed as follows: Group 1: Concise Light Cured White Sealant was applied without vibration; Group 2: same as in Group 1 but with vibration; Group 3: Single Bond Adhesive was applied, then Concise Light Cured White Sealant was applied without vibration; Group 4: same as in Group 3, but sealant was applied with vibration; Group 5: Concise Light Cured White Sealant was applied without vibration, then Z-100 composite was burnished over the sealant and light-cured; Group 6: same as in Group 5, but sealant was applied with vibration. Microvibe vibrating probe was used for sealant vibration. After 24-hour immersion in 2% basic fuchsin dye solution, specimens were sectioned, and dye and sealant penetration were scored using a stereomicroscope and color slides. Selected sectioned samples were observed under the SEM.

RESULTS

No statistically significant differences between the groups were observed for either dye or sealant penetration scores. In all groups, sealant penetration was more influenced by the shape, depth and residual debris of fissures than by the use of a vibrating probe.

On the diagnosis and management of neurocutaneous syndrome, a toxicity disorder from dental sealants

Neurocutaneous syndrome, a newly discovered toxicity disorder, is characterized by neurological sensations, pain, depleted energy, and memory loss as well as itchy cutaneous lesions that may invite various opportunistic infections. Components in the calcium hydroxide dental sealants Dycal, Life and Sealapex have been identified as sources of the observed symptoms. Sulfonamide and neurological toxicity issues are discussed, and three case histories are presented. Additional notes on zinc oxide, Fynal, IRM, and Sultan U/P sealers are also included. Diagnostic and management protocols at the Parasitology Center, Inc., are proposed.

In situ transformation of glass-ionomer into an enamel-like material

PURPOSE

To assess the nature of clinically detectable alterations in glass-ionomer after long-term clinical service.

METHODS

In addition to clinical macro pictures, SEM was carried out on replicas and on two sectioned primary molars SEM-EDAX analysis was performed to determine chemical transformation in the glass-ionomer. Also with SEM-EDAX, the composition was determined of a partially removed half-year old sealant.

RESULTS

The clinically observed altered optical aspect and increased hardness could be related with surface structure changes as identified by SEM. The changed glass-ionomer showed a continuous integration with the adjacent enamel. The SEM-EDAX analysis revealed an increase of calcium and phosphorus in the surface layer, tentatively suggesting a sort of additional "mineralization" of the material. This phenomenon was only observed for restorations that had minimally 2-3 years in vivo dwell time.

Root canal sealers induce cytotoxicity and necrosis

There are three types of the root canal sealers commonly used in clinical applications. They are calcium hydroxide base (Sealapex), zinc oxide-eugenol base (Canals), and epoxy-resin base (AH Plus). Elutable substances and degradation products from root canal sealers may gain access to periodontal tissue in a number of ways. The purpose of the present study was to evaluate the biologic effects of the root canal sealers on human oral cancer cell line (OC2). The tetrazolium bromide (MTT) assay was to evaluate the cell's survival rate. The DNA electrophoresis was used to evaluate the OC2 cell's DNA damage. The results demonstrated that the above root canal sealers' survival rates are in dose-dependent increase (p < 0.05). The toxicity of fresh mix group is higher than that of the mixed after 24h group. DNA fragmentation assay of sealer treated OC2 cells shows a smear layer pattern on the electrophoresis gel. There is no DNA damage found. The toxicity that regulated the cell death is not by the apoptic change of cells.

In vitro testing of all-in-one adhesives as fissure sealants

PURPOSE

To evaluate the clinical efficacy of all-in-one adhesives as fissure sealants.

METHODS

Resin-enamel bonded specimens were fabricated between polished and ground enamel surfaces using two all-in-one adhesives (One-Up Bond F and Xeno CF Bond) and two resin sealants (Teethmate F-1 and Helioseal F). Specimen beams were prepared and microtensile bond tests were performed at a crosshead speed of 1 mm/minute. The bond strengths obtained were subjected to one-way ANOVA and Scheffe's F test (P < 0.05: n=12 for each group). To evaluate the etching effect of phosphoric acid and the all-in-one adhesives, the treated enamel surfaces (37% phosphoric acid, 40% phosphoric acid, or all-in-one adhesives) were examined by FE-SEM.

RESULTS

The bond strengths of the two all-in-one adhesives tested to the polished enamel surface were significantly lower (P < 0.05) than to ground enamel. However, no significant differences (P > 0.05) were found between the polished and ground enamel surfaces for resin sealants using phosphoric acid. Under SEM examination, 37% or 40% phosphoric acid etched the enamel surface more than all-in-one adhesives.

An in vitro investigation to optimize the quality of compomer-based fissure sealants

PURPOSE

To evaluate if the in vitro quality of preventive fissure sealants made with compomer-based materials can be improved by modifying the method of application.

METHODS

Delton resin-based sealant, Dyract Flow and Dyract Seal compomers were used. The manufacturer's instructions were modified by prolonging the application time of the materials used and by applying the sealer in two layers. Extracted caries-free human molars were fissure sealed under standardized conditions and then exposed to a thermocycling procedure and a dye penetration test. Following the preparation of ground slices the samples were assessed by means of a light microscope and a scanning electron microscope. Statistical analysis of the results was done using a chi-square test.

RESULTS

The modified application of the two-compomer-based fissure sealers improved distinctly the quality of such fissure sealants. This was observed with respect to the criteria sealing ability, absence of pores in the sealant and complete filling of the fissure in wide as well as in narrow fissures. Compomer-based fissure sealants applied with the modified technique were equal to conventional resin-based composite fissure sealants regarding sealing ability and complete filling of the fissure. With respect to absence of pores, compomer-based sealants were superior to resin-based composite sealants.

Bonded amalgam sealants and adhesive resin sealants: five-year clinical results

Bonded amalgams were used as pit-and-fissure sealants without mechanical preparation. They were compared with resin-based pit-and-fissure sealants for retention over a 5-year period. Clinical examinations at 6 months, 1 year, 2 years, and 5 years revealed no difference between the two techniques. Although amalgam sealants may not be practical by themselves, they can be used to seal pits and fissures surrounding very conservative preparations, in the "preventive amalgam restoration." Conventional amalgam retentive features and 90-degree cavosurface margins may not be necessary when bonding is used with amalgam.

Bond strength of a sealant to primary and permanent enamel: phosphoric acid versus self-etching adhesive

PURPOSE

The objective of this study was to compare the effect of phosphoric acid and a self-etching adhesive on the short and long-term bond strength of a light-curing sealant to unground primary and permanent enamel.

METHODS

A light-curing resin sealant (Delton Light Curing Pit & Fissure Sealant-CLEAR) was bonded to the flattest, peripheral surface of 40 primary and 40 permanent molars following conditioning of the cleaned enamel with 38% phosphoric acid or with the self-etching adhesive Prompt L-Pop (N=10/group). After either 1 week or 1 year in water, shear bond strengths were measured. Failure mode was determined in a stereo microscope.

RESULTS

There was no significant difference in bond strengths between the phosphoric acid-etch and the self-etching adhesive groups, nor between the 1-week and 1-year results (P>.05). However, the bond strengths to primary enamel were lower than those to permanent enamel (P=.0021). The number of pure adhesive failures in each of the 8 groups varied between 0 and 3 (0-30%), and the remaining teeth displayed mixed adhesive-cohesive failures.

CONCLUSIONS

The self-etching adhesive studied seems an attractive alternative to the acid-etch technique for sealant application in young children where simplifications in the clinical procedure are warranted.

Microleakage of a pit-and-fissure sealant: effect of air-abrasion compared with classical enamel preparations

PURPOSE

The aim of this study was to assess the microleakage of a pit-and-fissure sealant after classical enamel preparations (prophylaxis followed by acid etching alone and mechanical widening with bur) and after air abrasion.

MATERIALS AND METHODS

Ninety noncarious freshly extracted third molars were randomly assigned to three groups of 30. In each group, the mesial halves of the fissures were treated with air abrasion and conditioned with acid etching for 15 s. In group 1, the distal halves were treated with acid etching alone. In group 2, the distal halves of the fissures were widened mechanically with a bur and etched for 15 s. In group 3, the distal halves were prepared with air abrasion alone. Then the sealant (Clinpro) was applied on the occlusal fissures of all teeth, according to the manufacturer's recommendations. The teeth were thermocycled and the samples placed in a 1% methylene blue dye solution. The teeth showing microleakage and the means of infiltration were assessed with an image analysis system.

RESULTS

The microleakage of sealants prepared with air abrasion alone displayed significantly greater microleakage (80%) (p < 0.0001) than the ones placed after prophylaxis and etching (13.33%), bur and etching (20%), or air abrasion and etching (22.2%). The samples prepared with air abrasion alone also showed the highest mean microleakage (1.14 +/- 1.4 mm) when compared to samples receiving prophylaxis and acid etching (0.12 +/- 0.41), bur and acid etching (0.08 +/- 0.26), or air abrasion and acid etching (0.09 +/- 0.4) (p < 0.05). No significant difference was noted between the three types of enamel preparation when etching was performed.

CONCLUSION

Air-abrasion treatment does not eliminate the need for etching the enamel surface before applying the sealant.

COMPARISON OF SHORT-TERM IN VITRO FLUORIDE RELEASE AND RECHARGE FROM FOUR DIFFERENT TYPES OF PIT-AND-FISSURE SEALANTS

OBJECTIVE

The purpose of this in vitro study was to assess the effects of four commercial fluoride-containing pit-and-fissure sealants on caries prevention.

MATERIALS AND METHODS

Four sealants containing fluoride, Fuji III, Fuji III LC (GC Co., Tokyo), Teethmate F-1 (Kuraray Medical Co., Osaka) and Helioseal F (Vivadent Co., Liechtenstein) were used to investigate fluoride release and recharge. Disk-shaped specimens prepared from each material were immersed in distilled water at a temperature of 37 degrees C. After seven days, acidulated phosphate fluoride solution (APF) was applied to each specimen, and it was then again immersed in distilled water for 14 days. We then determined how much fluoride had been released into the immersing water. Fuji III LC was used with APF solution to investigate the fluoride uptake.

RESULTS

Fuji III had the highest fluoride release, and Fuji III LC had the highest fluoride recharge. Helioseal F and Teethmate F-1 had almost no fluoride recharge. Fuji III LC/APF had a higher fluoride uptake to enamel than Fuji III LC.

CONCLUSIONS

These results suggest that GIC-sealants in the oral cavity can serve as a fluoride reservoir and contribute to retaining a low fluoride level in oral fluids, thereby preventing caries.

[Effect in vitro of environmental parameters on the release of fluoride ions from some materials used in dentistry]

The aim of this in vitro study was to evaluate the influence of calcium ions and pH on fluoride release from selected dental materials. The materials studied included a resin composite (Te-Econom), fissure sealant (Conseal F) and compomer (Freedom). Samples were placed for 7 days in artificial saliva with or without calcium ions and pH ranging from 4.5 to 7.5. Fluoride release from the studied materials was measured with an ion-selective electrode (Orion). The results demonstrate differing effects of calcium concentration and pH on fluoride release. The highest cumulative fluoride release was observed from Freedom and the lowest from Te-Econom. Addition of calcium ions to the medium reduced the release of fluoride.

Plaque and saliva fluoride levels after placement of fluoride releasing pit and fissure sealants

PURPOSE

The objectives of this study were to investigate the fluoride levels in plaque and saliva before and after applying fluoride-containing pit and fissure sealants, and compare the fluoride release of 2 types of sealants at the different time intervals.

METHODS

Eighteen children ages 6 to 9 years were randomly divided into 2 groups: Group 1--sealant containing fluorosilicate glass (Helioseal-F); and group 2--sealant containing methacryloyl fluoride-methyl methacrylate copolymer (Teethmate-F). Saliva and plaque samples were collected before and after the sealants were placed on their 4 first permanent molars. Fluoride levels were determined using the microdiffusion method. Fluoride concentrations before and after placing the sealants were analyzed by paired t test, and the fluoride concentrations between the 2 sealants were compared by t test, with the level of significance at 0.05.

RESULTS

There was no significant difference between salivary fluoride levels before and after sealant placement application in both groups. The plaque fluoride level of Helioseal-F group at 24 hours was significantly higher than the baseline level (P = .03), and was not different afterwards. The plaque fluoride levels after sealant with Teethmate-F were not significantly different when compared to the baseline. However, there were no significant differences between salivary and plaque fluoride levels of the 2 groups at different time intervals.

CONCLUSIONS

The groups sealed with sealant containing fluorosilicate glass showed significant increase of plaque fluoride level only at 24 hours after sealant placement.

Variables contributing to the quality of fissure sealants used by general dental practitioners

This study investigated the factors that could influence microleakage, penetration ability and the formation of resin tags of different sealants used in routine oral health care. One hundred and two caries-free extracted molars were divided into 34 groups of three teeth each. A questionnaire and three teeth were submitted to 34 dentists participating in the study. They completed the questionnaire anonymously based on their own clinical procedures. The teeth were then treated, corresponding to the questionnaires. The types of sealants were categorized into three groups: classical sealant, flowable composite and flowable compomer. The molars were thermocycled in water (5,000 cycles between 5 degrees C and 55 degrees C), then stained with 5% methylene blue for 24 hours. Each tooth was then sectioned longitudinally at three sites. Fissure type, microleakage and penetration ability of the sealants was evaluated with a computer-linked light microscope (25x magnification). Formation of resin tags at the enamel-sealant interfaces was examined using SEM. Variables thought to influence performance of the sealants were analyzed by multiple regression analyses. Classical sealants showed significantly lower microleakage than flowable composites and flowable compomers. Conventional etching with phosphoric acid was critical for sealant success. Agitating the etchant could improve the quality of sealing by decreasing microleakage significantly. In addition, the fissure types had a significant effect on the penetration ability of sealants.

A 5-year evaluation of two glass-ionomer cements used as fissure sealants

OBJECTIVE

To evaluate the retention and caries preventive effect of two glass ionomers used as fissure sealants: one resin modified glass ionomer (A) and one conventional glass-ionomer cement (B).

SAMPLES AND METHODS

The permanent first molars of 100 children, 6-8 years of age at the start of the study, were sealed. Material A was applied on one side (right side, upper, and lower) and material B was applied on the contralateral side (left side, upper, and lower) of the mouth. The control group was composed of 108 children who did not receive fissure sealant but received oral health education. After 5 years, 64.0% of the children of the experimental group and 73.0% of the children of the control group were available for reexamination.

RESULTS

Material A was completely lost in 74.2% and material B in 89.0% (Wilcoxon matched pairs test, P < 0.05). Total retention rate was 1.6% for materials A and B. After 5 years, caries increment was 21.5% for the experimental group and 34.2% for the control group (chi2-test, P < 0.05).

CONCLUSION

Sealing pits and fissures with glass-ionomer cements was effective in preventing caries.

Effects of different preparation techniques on the microleakage of compomer and resin fissure sealants

PURPOSE

The aim of this study was to compare the microleakage of a compomer and resin sealant in vitro using different surface preparation techniques.

METHODS

Microleakage of a compomer (Dyract Seal, DeTrey) and a resin sealant (Helioseal F, Vivadent) was investigated on 125 intact third molars. Materials and the surface preparation techniques were: Group 1--phosphoric acid (37%)+Helioseal F; Group 2--AlO2 air abrasion+Helioseal F; Group 3--nonrinse conditioner (NRC)+Prime&Bond+Dyract Seal; Group 4--phosphoric acid+Dyract Seal; Group 5--AlO2 air abrasion+Dyract Seal.

RESULTS

Pretreatment with phosphoric acid produced the lowest microleakage scores when applied with compomer and resin fissure sealants and there was no statistical difference (P>.05).

CONCLUSIONS

Compomer sealant used with a nonrinse conditioner (NRC) was not as successful as pretreatment with phosphoric acid etching, whereas AlO2 air abrasion pretreatment was ineffective in preventing microleakage in both sealants.

Microleakage and penetration ability of resin sealant versus bonding system when applied following contamination

PURPOSE

The purpose of this study was to evaluate the microleakage and penetration ability of sealing materials applied under different conditions of contamination.

METHODS

One hundred twenty extracted human molar teeth were randomly assigned to 12 groups. The treatment groups were defined by the combination of sealing materials (Concise; Optibond system; Optibond system plus Concise) and 4 surface conditions (no moisture and no saliva contamination; moisture contamination; dried saliva contamination; wet saliva contamination). Each tooth was subjected to thermal cycling (5,000 cycles at 5 degrees C-55 degrees C) with a dwell time of 30 seconds and dye immersion (5% methylene blue for 24 hours). Microleakage, penetration ability, and fissure types were examined after sectioning. Multiple regression analyses and the Tukey test were used for statistical analysis.

RESULTS

Concise showed significantly less microleakage than the Optibond system (P<.031) when the procedures were performed under no contamination or moisture contamination. However, when Concise was applied on the wet saliva-contaminated surfaces, considerably higher microleakage and unfilled areas were found compared to the use of Optibond alone or Optibond with Concise (P<.001).

CONCLUSIONS

When there is saliva contamination, the use of Optibond alone or with Concise is beneficial for decreasing microleakage and increasing the penetration ability of sealants.