The effectiveness of pit and fissure sealants

Shear Bond Strength and Film Thickness of a Naturally Antimicrobial Modified Dental Luting Cement

Although several natural plants and mixtures have been known and used over the centuries for their antibacterial activity, few have been thoroughly explored in the field of dentistry. Thus, the aim of this study was to enhance the antimicrobial activity of a conventional glass ionomer cement (GIC) with natural plant extracts. The effect of this alteration on the bond strength and film thickness of glass ionomer cement was evaluated and related to an 0.5% chlorohexidine modified GIC. Olive leaves (Olea europaea), Fig tree (Ficus carica), and the leaves and roots of Miswak (Salvadora persica) were used to prepare an alcoholic extract mixture. The prepared extract mixture after the evaporation of the solvent was used to modify a freeze-dried glass ionomer cement at three different extracts: water mass ratios 1:2, 1:1, and 2:1. An 0.5% chlorhexidine diacetate powder was added to a conventional GIC for the preparation of a positive control group (CHX-GIC) for comparison. The bond strength to dentine was assessed using a material-testing machine at a cross head speed of 0.5 mm/min. Failure mode was analyzed using a stereomicroscope at 12× magnification. The cement film thickness was evaluated in accordance with ISO standard 9917-1. The minimum number of samples in each group was n = 10. Statistical analysis was performed using a Kruskal–Wallis test followed by Dunn’s post hoc test for pairwise comparison. There was a statistically insignificant difference between the median shear bond strength (p = 0.046) of the control group (M = 3.4 MPa), and each of the CHX-GIC (M = 1.7 MPa), and the three plant modified groups of 1:2, 1:1, 2:1 (M = 5.1, 3.2, and 4.3 MPa, respectively). The CHX-GIC group showed statistically significant lower median values compared to the three plant-modified groups. Mixed and cohesive failure modes were predominant among all the tested groups. All the tested groups (p < 0.001) met the ISO standard of having less than 25 µm film thickness, with the 2:1 group (M = 24 µm) being statistically the highest among all the other groups. The plant extracts did not alter either the shear bond strength or the film thickness of the GIC and thus might represent a promising additive to GICs.

A comparative evaluation of retention of pit and fissure sealants placed with conventional acid etching and Er,Cr:YSGG laser etching: A randomised controlled trial

Aim: The aim of this study was to compare the retention rates of sealant placed either with conventional acid etching or Er,Cr:YSGG laser pretreatment of enamel surface. Materials and methods: This is a prospective, single blind randomised controlled clinical trial enrolling 200 permanent first molars in 50 patients, aged 6-12 years for sealant placement. Study followed split mouth design where each side of the arch was randomly allocated to the two treatment group. Group A(Acid etch group): 37 % phosphoric acid (Scotchbond, 3M ESPE, Seefeld, Germany) was applied for 15 seconds, rinsed with water for 20 seconds and then air-dried using air spray. Group L(Laser etch group): Fissures were prepared with an Er,Cr:YSGG laser system (Waterlase, BIOLASE Technology, San Clemente, CA, USA) emitting photons at a wavelength of 2.78 µm. Laser irradiation at 1.5 W (60% air and 40% water), in a noncontact mode, with a repetition rate of 20 Hz for 10seconds was used. Pit and fissure sealant (3M ESPE, Clinpro) was applied and cured for 20 seconds. One blinded, calibrated examiner, who was unaware of which preparation method has been used and who was not involved in the treatment procedures, evaluated the sealant at baseline and at 3, 6, 9 and 12 month follow-up visits. Results: It was observed that overall retention rate in group A was slightly higher as compared to group L at all time periods, however, the difference was statistically non-significant (p-value>0.05).

CONCLUSION

Er,Cr:YSGG laser etching is comparable to acid etching in terms of retention and patient acceptability.

A Review of Glass-Ionomer Cements for Clinical Dentistry

This article is an updated review of the published literature on glass-ionomer cements and covers their structure, properties and clinical uses within dentistry, with an emphasis on findings from the last five years or so. Glass-ionomers are shown to set by an acid-base reaction within 2–3 min and to form hard, reasonably strong materials with acceptable appearance. They release fluoride and are bioactive, so that they gradually develop a strong, durable interfacial ion-exchange layer at the interface with the tooth, which is responsible for their adhesion. Modified forms of glass-ionomers, namely resin-modified glass-ionomers and glass carbomer, are also described and their properties and applications covered. Physical properties of the resin-modified glass-ionomers are shown to be good, and comparable with those of conventional glass-ionomers, but biocompatibility is somewhat compromised by the presence of the resin component, 2 hydroxyethyl methacrylate. Properties of glass carbomer appear to be slightly inferior to those of the best modern conventional glass-ionomers, and there is not yet sufficient information to determine how their bioactivity compares, although they have been formulated to enhance this particular feature.

Comparison of Acid Versus Laser Etching on the Clinical Performance of a Fissure Sealant: 24-Month Results

Objective

To compare the clinical performance of a pit and fissure sealant placed with the use of different enamel preparation methods, i.e. acid or Er,Cr:YSGG laser etching, over 24 months.

Methods

Sixteen subjects (15 female, 1 male) with no restorations or sealant present on their fissures and no detectable caries participated. Using a table of random numbers, a total of 112 sealants (56 with acid-etching, 56 with laser etching) were placed on the permanent premolar and molar teeth. All restorative procedures except for application of the laser were performed by the same dentist. After completion of the fissure preparation either with acid or laser, the adhesive was applied; then a pit and fissure sealant, Clinpro Sealant, was placed and polymerized. Clinical evaluations were done at baseline and at 6-, 12-, 18-, and 24-month follow-up visits by two calibrated examiners, who were unaware of which etching method had been used. The retention of sealants and caries were evaluated with the aid of a dental explorer and an intra-oral mirror. Each sealant was evaluated using the following criteria: 1=completely retained; 2= partial loss; 3= total loss. The Pearson chi-square test was used to evaluate differences in the retention rates among the sealants used with different etching methods.

Results

All patients attended the 24-month follow-up visit and all sealants were evaluated (total recall rate 100%). At the end of 24 months, 83.9% of the sealants from laser group and 85.7% of those from acid-etch group were recorded as “completely retained”. There were no statistically significant differences in retention rates among the preparation methods after all evaluation periods (p&gt;0.05). No statistically significant differences were found between the retention rates of premolar and molars at each evaluation period. No secondary caries was detected in association with any sealants. Conclusion: The clinical performance of fissure sealants placed after acid or Er,Cr:YSGG laser etching was similar.

Heat-treated glass ionomer cement fissure sealants: retention after 1 year follow-up

OBJECTIVE

The aim of this study was to assess the retention rate of glass ionomer cement (GIC) fissure sealants heated during setting time.

METHODS

One hundred and twelve teeth with well-delineated fissure morphology were sealed with composite resin and GIC. Composite resin (Helioseal F, Vivadent) was used in control group A (56 teeth). GIC (Fuji VII, GC) was applied using split-mouth design with conditioning in group B (26 teeth) and without surface conditioning in group C (30 teeth). GIC was heated with external heat source (Elipar Trilight, Espe) for 40 s during the setting time according to the manufacturer's instructions. Fissure sealants were evaluated 1 year after clinical service.

RESULTS

Retention rate in group A was 80.4% after 1 year of clinical service. Group B showed retention rate of 30.8%, and group C of 26.7%. Two new caries lesions were detected in groups B and C. Significant differences in retention between the composite group and GIC groups were obtained by Kruskal-Wallis and Mann-Whitney tests.

CONCLUSION

It could be concluded that retention rate of GIC sealing treated with heat during setting time was significantly lower than retention of conventional composite resin. The heating procedure during setting of GIC sealants cannot be recommended as routine treatment in clinical practice.

Different dental care setting: does income matter?

In this paper we consider the use of mobile dental clinics as a means of improving access to dental care among primary school children in Southern Thailand by reducing the opportunity cost of service use to parents. Parents' willingness to pay (WTP) is measured for three different services provided in a community hospital dental clinic and a school-based mobile clinic. Although the service setting does not affect significantly the WTP for treatment directly, the estimated positive association between WTP and income is modified by setting. The results indicate that the potential for mobile clinics to increase utilization of services among primary school children is associated with parents' income, with the difference in valuation of dental services between the two settings being less among lower income parents than higher income parents. However, even among lower income parents our results indicate that the potential for increasing service utilization among children depends on the improvements in access associated with the mobile clinic not being achieved at the opportunity cost of lower levels of effectiveness.

Natural history of treatment outcomes of permanent first molars

BACKGROUND

Few studies have used insurance claims data to retrospectively assess the natural history--a natural process or flow of events without any special interventions--and treatment outcomes of teeth with dental sealants.

METHODS

The authors constructed treatment outcome trees (TOTs) from the Iowa Medicaid claims and eligibility data (1996-2000) of continuously enrolled 6-year-old children who routinely used Medicaid dental services. The authors used the TOTs to compare the restorative treatments of sealed permanent first molars with those of nonsealed permanent first molars.

RESULTS

Forty percent of routine utilizers received a sealant during the four-year period. Overall, 25 percent of molars received at least one restoration. Sealed molars were less likely to receive further restorative treatment than were nonsealed molars (13 versus 29 percent). Sealed molars had fewer extensive restorative treatments (crowns, endodontic therapy and extractions) than did nonsealed molars. The median time to restorative treatment of the sealed molars also was greater than that of the nonsealed molars. All four first molars had comparatively similar patterns of subsequent care.

CONCLUSIONS

Permanent first molars with sealants received less subsequent restorative treatment than did those without sealants. TOTs are useful tools for identifying necessary outcome information needed for program evaluations.

CLINICAL IMPLICATIONS

Greater use of sealants could reduce the need for subsequent treatment and prolong the time until treatment may be necessary for permanent first molars.

Acid-etched and erbium:yttrium aluminium garnet laser-treated enamel for fissure sealants: a comparison of microleakage

OBJECTIVES

A pilot study aimed to compare the microleakage of pit and fissure sealants in acid-etched and Erbium:Yttrium Aluminium Garnet (Er:YAG)-treated enamel.

METHODS

Forty permanent noncarious young molars and premolars, which were extracted for orthodontic reasons, were selected. The teeth were divided into four groups, with five molars and five premolars in each group. The groups were treated as follows: (1) group A--laser irradiation of the enamel of the occlusal surface without contact and in scanning mode was carried out using an Er:YAG laser, placement of sealant material, light curing, and thermocycling between 6 degrees and 55 degrees C; (2) group B--the same as group A, but with no thermocycling; (3) group C--acid etching of the enamel surface, placement of sealant material, light curing and thermocycling; and (4) group D--the same as group C, but with no thermocycling. After being immersed in 1% methylene blue solution, all teeth were sectioned in the mesio-distal dimension into four slices. Images of the slices were then scanned to a Macintosh G3 computer and examined for marginal leakage. Leakage was measured by the degree of dye penetration. Three independent examiners evaluated the dye penetration.

RESULTS

No penetration of dye material was observed in any of the slices in any of the four groups by any of the examiners.

CONCLUSIONS

No difference in microleakage was seen between lasing or acid etching, and therefore, the results of the present study would suggest that the technique may be efficacious.

Dental sealant longevity in a cohort of young U.S. naval personnel

BACKGROUND

The U.S. Navy emphasizes caries prevention and encourages the placement of dental sealants on the caries-susceptible teeth of patients at risk of developing caries. The authors analyzed dental records to assess the longevity of dental sealants placed in naval personnel.

METHODS

A cluster sample of dental records from 1,123 personnel who entered naval service in 1997 was drawn from eight Navy dental treatment facilities. The authors determined the number of sealants provided, the number of sealants that failed over the observation period (1997-2001), the dates of sealant failure and the longevity of sealants placed during and after recruit training.

RESULTS

A total of 319 personnel received sealants during their first two years of service. The authors evaluated 1,467 sealed teeth. They followed the sealants for an average of 35 months. They noted 179 sealant failures in 102 subjects; 69 previously sealed teeth required sealant replacement, and 110 sealed teeth required restoration of the occlusal surface. Among those sealants that failed, the mean length of time from placement to failure was 26 months. Sealant failure rates were significantly higher among subjects at moderate risk or high risk of developing caries than among subjects at low risk.

CONCLUSIONS

After an average of 35 months, 87.8 percent of the sealants placed in this population were retained and functional. Subjects who were at moderate or high risk of developing caries demonstrated significantly higher sealant failure rates than those at low risk of developing caries.

CLINICAL IMPLICATIONS

Dental sealants can be retained successfully in adults. They should be considered a viable treatment alternative for adult patients who are susceptible to caries; however, patients at elevated risk of developing caries may require more frequent re-evaluation and maintenance to achieve maximum benefit.

In-vitro microleakage of repaired fissure sealants: a randomized, controlled trial

The aim of this study was to investigate whether differences in surface treatment prior to repair influenced the seal of a resin fissure sealant placed on the occlusal surfaces of permanent molar teeth.

SETTING

In-vitro study.

SAMPLE AND METHODS

One hundred and twenty-eight extracted human first and second molars were randomly allocated to one of four groups of 32 teeth each. A light cured, unfilled, opaque resin fissure sealant (Delton) was placed on their occlusal surface following cleaning by prophylaxis and acid etching. Following storage in artificial saliva (Saliva Orthana) for a week, duplication of sealant failure was carried out. The teeth were then subjected to one of four different surface treatments: Group 1: with a slow-speed prophylaxis brush followed by acid etching (control method); Group 2: a slow-speed bur and acid etching; Group 3: air abrasion and acid etching; and Group 4: acid etching and application of a bonding agent. Following a further week of storage in artificial saliva two layers of impermeable varnish were applied to the nonocclusal surfaces of the teeth; their apices were then sealed with wax and the teeth were immersed in 1% methylene blue for 48 h. The teeth were then sectioned (ISOMET 1000) to achieve three cuts resulting in a maximum of four blocks, i.e. six surfaces per tooth. A total of 715 sections from 126 teeth were scored for microleakage on the intact and repaired side of the fissure sealant.

RESULTS

Statistical analysis did not demonstrate any one single method of repair to be superior to the control method for reapplication of the sealant.

CONCLUSION

All four techniques compared in this study seem to be acceptable for replacing or repairing lost or fractured fissure sealants. As prophylaxis with a brush rotating at slow speed followed by acid etching, which probably represents current practice, is also the simplest technique that can be practised on children, it is therefore recommended.

Caries-preventive effect of fissure sealants: a systematic review

The objectives of this study were to evaluate systematically the evidence of the caries-preventive effect of fissure sealing of occlusal tooth surfaces and to examine factors potentially modifying the effect. The search strategies included electronic databases, reference lists of articles, and selected textbooks. Inclusion criteria were randomized or quasi-randomized clinical trials or controlled clinical trials comparing fissure sealing with no treatment or another preventive treatment in children up to 14 years of age at the start; the outcome measure was caries increment; the diagnostic criteria had been described; and the follow-up time was at least 2 years. Inclusion decisions were taken and grading of the studies was done independently by two of the authors. The main measure of effect was relative risk reduction. Thirteen studies using resin-based or glass ionomer sealant materials were included in the final analysis. The results showed that most studies were performed during the 1970s and a single application had been utilized. The relative caries risk reduction pooled estimate of resin-based sealants on permanent 1st molars was 33% (relative risk = 0.67; CI = 0.55-0.83). The effect depended on retention of the sealant. In conclusion, the review suggests limited evidence that fissure sealing of 1st permanent molars with resin-based materials has a caries-preventive effect. The evidence is incomplete for permanent 2nd molars, premolars and primary molars and for glass ionomer cements. Overall, there remains a need for further trials of high quality, particularly in child populations with a low and a high caries risk, respectively.

Comparing the costs of three sealant delivery strategies

We analyzed the cost-effectiveness of 3 sealant delivery strategies: Seal all (SA), seal children assessed to be at risk by screening (TARGET), and seal none (SN). We assumed a nine-year analytic horizon, a 3% discount rate, and zero screening costs. Estimates for sealant costs ($27.00) and restoration costs ($73.77), annual caries increment (0.0624 surfaces), sealant failure rate (20% in yr 1 and 3% thereafter), annual amalgam failure rate (4.6%), and sensitivity (0.635) and specificity (0.795) of screening were obtained from published studies. Under baseline assumptions, TARGET dominated (cost less and reduced caries) SA and SN. If annual caries increment exceeded 0.095 surfaces, SA dominated TARGET, and if increment exceeded 0.05 surfaces, TARGET dominated SN. If sealant costs decreased to $6.00 (reported cost for school programs), TARGET dominated SN for caries increments exceeding 0.007 surfaces, and SA dominated TARGET for caries increments exceeding 0.034 surfaces.

Targeting dental sealants in school-based programs: evaluation of an approach

Several guidelines have been published in the United States to promote the appropriate use of sealants in both individual care and public health programs. Targeting sealants to children and teeth at high risk for dental caries has been accepted as a desirable strategy in school-based programs. However, there is little evidence to show that programs are complying with these guidelines. This report examined the extent to which sealants were targeted to high-risk children at 11 different school-based programs in New York State. Data on 3357 children ages seven to nine were analyzed. The percent of children receiving sealants ranged from 41% to 88%. While in two sites (St. Lawrence & Onondaga) fewer than 52% of the children received sealants; more than 73% received sealants in the remaining nine sites (P < 0.05). The results suggest that there was a wide variation in the implementation of the guidelines for sealant use. Some reasons for not adhering to the guidelines were: difficulty in assuring parents and local dentists that some children were not at risk for caries; lack of confidence in the risk-assessment method; uncertainty regarding what constitutes deep pits and fissures; fear of misclassifying children and requests by school administrators, parents and local dentists that all children should benefit from preventive measures.

[Effectiveness of fissure sealants in child population at high risk of caries]

OBJECTIVES

To asses the effectiveness of fissure sealants in a high risk infant population and to evaluate the criteria to determine when to apply them.

DESIGN

Prospective cohort study.

SETTING

Primary care.

PARTICIPANTS

607 scholars that are included at the age of 6 years and followed for 4,5 years.Intervention. We have defined three groups. Groups I and II were included in a dental preventive program with and without fissure sealants in the first permanent molars, respectively, and group III received no preventive measures at all.

MAIN MEASUREMENTS

The dental explorations according to WHO recommendations were conducted before entering the study, at the age of six years, after the fissure sealant were applied, at the age of eight years and finally 4.5 years after the beginning.

RESULTS

After 4.5 years group I had a CAOD index of 0.59, group II 0.79 and group III 1.52 (P<.001). Group III has 2.57 times greater risk the group I of suffering caries in the permanent teeth.

CONCLUSIONS

The application of occlusive fissure sealant in the first permanent molar of an infant high risk population has a protective effect on dental caries. Therefore occlusive fissure sealant should be offered to all scholars because those without neither the preventive program nor occlusive fissure sealant had a significantly higher risk of caries.

Treatment outcomes and costs of dental sealants among children enrolled in Medicaid

OBJECTIVES

This retrospective cohort analysis of children enrolled in the North Carolina Medicaid program compared the likelihood of restorative treatments and associated cumulative Medicaid expenditures for teeth with or without dental sealants.

METHODS

We assessed the dental experience of the cohort of 15 438 children from 1985 to 1992 on the basis of enrollment and claims files. We conducted regression analyses for outcomes (caries-related services involving the occlusal surface [CRSOs] of permanent first molars) and cumulative expenditures, controlling for characteristics of the child, the treating dentist, and the child's county of residence.

RESULTS

Overall, 23% of children received at least 1 sealant and 33% at least 1 CRSO. Sealants were effective in preventing CRSOs, although the degree of effectiveness was highest for children with the greater levels of CRSOs before sealant placement. Estimated cumulative Medicaid expenditures indicated expenditure savings from sealants within 2 years of application for children with 2 or more prior CRSOs.

CONCLUSIONS

Sealant placement was associated with expenditure savings to Medicaid for certain high-risk children, so Medicaid and, more broadly, society will benefit by providing for sealant placement in these children.

Sealant use and placement techniques among pediatric dentists

BACKGROUND

Pit and fissure sealant use varies widely among dentists. The authors conducted a survey to determine the current variations and patterns of sealant placement among pediatric dentists.

METHODS

The authors mailed a 20-question survey to American Academy of Pediatric Dentistry members from six states, who represented one-third (1,210) of the membership, as well as to all 52 pediatric dentistry departments in U.S. dental schools. The authors examined selection criteria, placement techniques, evaluation methodologies, and the one- and three-year estimated success and reapplication rates of sealant placement.

RESULTS

The response rates were 70 percent for practitioners and 90 percent for dental schools. Approximately 80 percent of respondents said they sealed caries-free and questionable carious surfaces. Only 20 percent of the respondents said they sealed incipient carious surfaces; none said they would seal overt caries. Surface preparation was used always or sometimes by 87 percent of the respondents. The estimated one- and three-year sealant retention rates were 89 percent and 78 percent, respectively, for practitioners and 83 percent and 71 percent, respectively, for dental schools.

CONCLUSIONS

The survey demonstrated wide variations in selection criteria, placement techniques and evaluation methodologies, yet showed remarkable similarities between practitioners and dental schools. The reported retention rates were consistent with those reported in the literature.

PRACTICE IMPLICATIONS

The survey results suggested that pediatric dentists were searching for evidence-based selection criteria and a technique protocol for sealant placement that improved clinical success. The wide technique variations reported were likely a result of training diversity, diagnostic uncertainty, technique and material sensitivity, and an attempt to improve the success rate.

A comparison of sealant placement techniques and 12-month retention rates

OBJECTIVE

This study compared time required and 12-month retention for two methods of sealant placement: traditional acid-etch technique and air-abrasion technique without acid etch.

METHODS

Sealants were placed on the permanent first molars of 84 children in grades 1-4 who were randomly assigned to treatment groups. All sealants were placed in a school setting by the same clinician. Chair time required for sealant placement was recorded, and retention rates were determined for each technique 12 months after placement.

RESULTS

Mean chair time for placement of sealants on four first molars using the air-abrasion technique was significantly less than for the acid-etch technique (7:36 minutes vs 10:56 minutes). Fifty-eight children were available at 12-month follow-up; an examiner not involved in sealant placement and masked as to the technique used determined retention. Rates of complete retention for occlusal surfaces were not significantly different for the two techniques, although the rate for acid etch was higher than that for air abrasion (95% vs 87%). The complete retention rates for the acid-etch technique were significantly higher than air abrasion for buccal and distolingual surfaces. These rates were 65 percent and 58 percent, respectively, for acid etch and 6 percent and 28 percent, respectively, for air abrasion.

CONCLUSION

Although more research is needed to improve air-abrasion applications, it does not appear that air abrasion without acid etching offers a significant advantage over traditional sealant placement methods and, in fact, appears to be inferior to the acid-etch technique for use in public health settings.

Prevention of early childhood caries

This paper reviews the methods used for the prevention of early childhood caries (ECC). The education of mothers or caregivers to promote healthy dietary habits in infants has been the main strategy used for the prevention of ECC. This review found that education has a modest impact on the development of ECC. While education should be promoted especially in high risk communities and population groups (low-income families and native populations), it should not be the only preventive strategy of ECC. Early screening for signs of caries development, starting from the first year of life, could identify infants and toddlers who are at risk of developing ECC and assist in providing information to parents about how to promote oral health and prevent the development of tooth decay. High risk children include those with early signs of ECC, poor oral hygiene, limited exposure to fluorides, and frequent exposure to sugary snacks and drinks. These children should be targeted with a professional preventive program that includes fluoride varnish application, fluoridated dentifrices, fluoride supplements, sealants, diet counseling, and chlorhexidine. Prevention of ECC also requires addressing the social and economic factors that face many families where ECC is endemic.

Dental caries and dental fluorosis among schoolchildren who were lifelong residents of communities having either low or optimal levels of fluoride in drinking water

OBJECTIVE

This paper reports findings for dental caries and dental fluorosis in 8-10- and 13-16-year-old schoolchildren who were lifelong residents of communities having either naturally occurring low (Broken Bow and Holdrege, NE; < 0.3 ppm) or optimal (Kewanee, IL; 1 ppm) levels of fluoride in drinking water.

METHODS

Findings are reported for participants who received both dental caries and dental fluorosis examinations (n = 495). The DMFS and TSIF indices, respectively, were used to assess dental caries and dental fluorosis.

RESULTS

The mean DMFS score adjusted for age, sealant presence, and fluoride use was significantly lower in Kewanee (1.8) than was the adjusted mean caries score in either Holdrege (2.9) or Broken Bow (3.6). Adjusted mean DMFS scores in Broken Bow and Holdrege were not statistically different. The mean percent of fluorosed tooth surfaces per person, adjusted for age and use of dietary fluoride supplements, was similar in the three communities (approximately 15%); more than 80 percent of tooth surfaces in all participants were fluorosis-free.

CONCLUSIONS

Findings from the present study suggest that water fluoridation still is beneficial and that dental sealants can play a significant role in preventing dental caries. In addition, findings from this survey appear to support the premise that the difference in dental fluorosis prevalence between fluoridated and nonfluoridated communities has narrowed considerably in recent years.

Bonded amalgam sealants: two-year clinical results

The authors used bonded amalgams as pit and fissure sealants without mechanical preparation. They compared the two-year retention of the bonded amalgams with that of resin-based pit and fissure sealants. Clinical examinations at six months, one year and two years revealed no difference between the retention of the two sealants. This technique opens up the possibility of using bonded amalgam in pits and fissures surrounding very conservative preparations in a preventive amalgam restoration.

The relationship between the number of sound, decayed, and filled permanent tooth surfaces and the number of sealed surfaces in children and adolescents

OBJECTIVES

The purpose of this investigation was to determine the prevalence of sound, decayed, filled, and sealed permanent tooth surfaces for children and adolescents from three fluoridated communities in British Columbia and to develop a predictive model of sealant use that included the dental caries status of tooth surfaces.

METHODS

Children in grades 2 and 3 (n = 2,715) and adolescents in grades 8 and 9 (3,317) were surveyed to determine the prevalence of sound, decayed, filled, and sealed permanent tooth surfaces. The DMFS index, modified to include incipient (D1) and cavitated (D2) lesions, was used to measure the status of all tooth surfaces. The prevalence of D1D2MF and sealed tooth surfaces was estimated by age group and tooth type. Logistic regression models were developed to analyze the association between a number of independent variables and sealant use.

RESULTS

About 60 percent of surveyed students had one or more sealants present, with a mean of 3.2 sealants per subject. Of all pit and fissure surfaces on permanent first molars, 23.4 percent and 20.1 percent were sealed for the 11 years and younger and 12 years and older age groups, respectively. For these same two age groups, the percentages of pit and fissure surfaces that were decayed and filled were 6.7 percent and 19.7 percent, respectively. For both age groups combined, 10.8 percent and 23.7 percent of all pit and fissure surfaces on second molars and premolars, respectively, were sealed. The prevalence of decayed and filled pit and fissure surfaces was 5.6 percent and 1.8 percent, respectively, for second molars and premolars. Premolars were being sealed at a rate of 13 to 1 compared to the number of decayed and filled surfaces. Logistic regression failed to identify meaningful predictors of sealant use.

CONCLUSIONS

Results from this study found an increase in the prevalence of sealants in the three communities surveyed, yet failed to identify criteria used by dentists or auxiliaries when making decisions about sealant placement. Professional education in the appropriate use of sealants may be necessary.

An evaluation of a primary preventive dental programme in non-fluoridated areas of Victoria, Australia

A primary preventive dental programme targeting adolescents living in non-fluoridated areas of Victoria, Australia was evaluated for a three-year period. The programme comprised annual placement or replacement/repair of fissure sealants combined with a weekly 0.2 per cent sodium fluoride mouthrinse and was evaluated in terms of acceptance by the providers and the community to which it was directed. Acceptance was measured using accessibility, availability, continuity, quality of care, role responsibility, provider and consumer satisfaction, and cost-effectiveness. In general, the programme was considered to represent an acceptable model for future preventive interventions, although there were areas of its design that were found to require improvement. In particular, deficiencies in the manner in which the fluoride mouthrinsing component was delivered indicate that further investigation would be required before a recommendation to adopt its use could be made.

The retention of pit and fissure sealants placed in primary school children by Dental Health Services, Victoria

The benefit of a public sector sealant programme for children in Australia is yet to be established. This study evaluated sealants placed by therapists of the School Dental Service in Victoria, between 1989 and 1994, on permanent teeth of children in 15 primary schools in Melbourne. Seven hundred and seventy four children aged 6-12 years were examined in school dental clinics by six calibrated examiners. A total of 5363 sealants placed on 2875 permanent teeth (including 2616 first molars, 91 per cent of sample) up to four and a half years previously was examined. Values for complete and partial sealant retention were highest for premolars (86 per cent, 9 per cent respectively, total 95 per cent); similar for occlusal surfaces of maxillary and mandibular first molars (63 per cent, 30 per cent; 62 per cent, 32 per cent respectively) and buccal pits of mandibular molars (66 per cent); and low for pits/fissures of Carabelli's cusps of maxillary molars (44 per cent). Cross-sectional examination up to 24 months for both maxillary and mandibular first molars indicated average values of 67 per cent complete retention, 27 per cent partial retention, 6 per cent missing; thereafter complete retention decreased and partial retention increased. Sealant failures in the six months post-placement were attributed to technique failure. Regardless of sealant retention, caries experience was low under partially retained or missing sealants (4.5 per cent) and completely retained sealants (0.4 per cent). It is concluded that the SDS sealant programme is a sound preventive dental public health approach.

A 48-month survival analysis comparing sealant (Delton) with fluoride varnish (Duraphat) in 6- to 8-year-old children

The objective of this study was to compare Delton visible-light fissure sealant with Duraphat fluoride varnish in the prevention of occlusal caries in permanent first molars. A 48-month clinical trial was carried out in three groups of 6- to 8-year-old schoolchildren: a sealant group (104 children), in which Delton was used; a varnish group (112 children), in which Duraphat was used; and a control group (128 children). Sealant or varnish was applied to all sound permanent first molars, according to group. Replacement (sealant) and reapplication (varnish) was carried out every 6 months. A survival analysis was used to describe the molar failures over time in the three groups. A Cox proportional hazards regression model was built to test the influence of group on molar failure. The median survival times were 28.6 months for the control molars and more than 48 months for both sealed and varnished molars. The Cox model indicated a hazard ratio of 0.177 for the sealant vs control comparison, 0.463 for varnish vs control and 0.382 for sealant vs varnish.

Fissure sealing with a light-cured resin-reinforced glass-ionomer cement (Vitrebond) compared with a resin sealant

The aims of the present study were to evaluate the retention and caries-preventive effect of a single application of a light-cured resin-reinforced glass-ionomer cement (Vitrebond) in pits and fissures of newly erupted permanent first and second molars, when compared with a single application of a resin-based sealant (Concise White Sealant) during a 3-year period. The study group comprised 73 pairs of contralateral newly erupted permanent first and second molars (136 fissure sites) in 53 children (29 girls, 24 boys). A split-mouth experimental design was used in which the two sealants were randomly allocated to one of the teeth within each pair. Acid etching was not used before application of the glass-ionomer cement. The sealed teeth were checked for retention and caries after 1, 6, 12, 24 and 36 months. The resin-based sealant was almost totally retained after 3 years (97%) and there was no caries in these teeth. The glass-ionomer cement was increasingly lost and could be observed in only 9% of the sealed sites after 3 years. Carious lesions developed in 10 (7.4%) sites (nine teeth, seven children). It was concluded that the resin-based sealant is superior to the glass-ionomer cement in preventing caries, and that the superior retention of the resin probably is an important factor for this.

Intra-oral distribution and impact of caries experience among South Australian school children

This report describes the intra-oral distribution of caries and frequency of reported toothache using data from 9690 South Australian children aged 5-15 years. School dental therapists and dentists recorded dmfs and DMFS data and a questionnaire to parents sought information about toothache and its impact. There were higher levels of caries experience in deciduous teeth (mean 6-year-old dmfs = 2.61) compared with permanent teeth (mean 12-year-old DMFS = 1.15). In the deciduous dentition: between 11.4 per cent (9-year-olds) and 37.7 per cent (5-year-olds) of total dmfs was present as untreated decay; between 39.1 per cent (7-year-olds) and 42.8 per cent (10-year-olds) occurred on interproximal surfaces; and between 2.0 per cent (10-year-olds) and 27.8 per cent (5-year-olds) occurred in anterior teeth. In the permanent dentition, the majority of permanent caries experience occurred as fillings in pits and fissures of first molars and involved a single surface. Between 11.8 per cent (5-year-olds) and 31.8 per cent (12-year-olds) of children had a reported history of toothache, although the figure exceeded 50 per cent among children with all three forms of pit/fissure, interproximal and smooth-surface caries experience. The observed pattern of caries provides the basis for continued use of fissure sealants as a preventive measure among school children.

Effectiveness of visible light fissure sealant (Delton) versus fluoride varnish (Duraphat): 24-month clinical trial

The present study compares visible-light Delton with Duraphat fluoride varnish for the prevention of occlusal caries in permanent first molars. A clinical trial was carried out in three groups of 6-8-yr-old schoolchildren: a sealant group (100 children), in which Delton light-polymerized fissure sealant was applied to permanent first molars; a varnish group (98 children), in which Duraphat was applied to permanent first molars; and a control group (116 children). Replacement (sealant) and reapplication (varnish) was carried out every 6 months. Percent effectiveness at 24 months (percentage of saving from caries taking molars as analysis unit) for those molars initially healthy and with complete occlusal eruption was analyzed. 272, 252 and 238 molars met the inclusion criteria in the control, varnish and sealant groups, respectively. Of these, 45.2%, 28.2% and 10.5% developed caries after 24 months. The effectiveness was greater in the sealed molars than in the varnished molars (62.7%).

The prevalence of dental sealants in the US population: findings from NHANES III, 1988-1991

Over the past decade, dental sealants have become recognized as an important adjunct to the use of fluorides in the prevention of dental caries. The most recent national survey of oral health in children conducted in 1986-1987 found that only 7.6% of children had any sealed teeth. As part of the oral health component of the 1988-1991 Third National Health and Examination Survey (NHANES III-Phase 1), the prevalence of dental sealants in children, adolescents, and adults was determined. The presence of dental sealants on posterior teeth (excluding third molars) and maxillary lateral incisors was recorded by visual and tactile methods during the dental caries examination. Findings in this paper are based on those examined persons having at least one sealable primary tooth for children aged 2-11 years (n=3,792); at least one sealable premanent tooth for persons aged 18 years and over (n=7,146). During 1988-1991, about 18.5% of US children and youth ages 5-17 had one or more sealed permanent teeth. A significantly higher percentage of non-Hispanic whites had sealants in comparison with their non-Hispanic black and Mexican-American counterparts (for all contrasts, p<0.001). As expected, molar teeth were the most frequently sealed tooth type. Only 1.4% of US children ages 2-11 had at least one sealed primary tooth. The prevalence of dental sealants decreased in the US adult population with increasing age; 5.5% of adults ages 18-24 had at least one sealed permanent tooth. Data collected from NHANES III-Phase 2 (1991-1994) will be analyzed to determine if the upward trend in sealant use continues.

Influence of enamel prophylaxis on wettability of three commercially available orthophosphoric acids

An in vitro study was performed to assess the wettability of orthophosphoric acid after different procedures for cleaning the enamel surface. Ninety noncarious third molars were randomly distributed into three groups with different enamel surface treatments: an air-powder polisher unit, prophylaxis pastes, and no enamel surface cleaning. Three commercially available orthophosphoric acids were used, and there were 10 teeth in each group. Acid viscosity values and contact-angle measurements were obtained. Each enamel surface was also examined with the scanning electron microscope. Results suggested that the surface treatment with which the best spreading of the acid solution was attained was the air-powder polisher. The least spreading of the acid was obtained with prophylaxis pastes, in which contact angles were even higher than those obtained on the untreated enamel surface. The 3M acid solution was the one that showed the best spreading onto the enamel surface.

The impact of recent changes in the epidemiology of dental caries on guidelines for the use of dental sealants

This paper reviews recent changes in the epidemiology of dental caries and assesses their potential impact on the diagnosis and management of the disease and the planning and operation of sealant programs. These changes, such as the decline in caries and slowing of the rate of progression of the disease, have important implications for diagnosing and treating incipient lesions, predicting caries risk, and conducting effective disease preventive programs. Traditional paradigms for restoring carious lesions are being replaced by newer strategies that emphasize disease prevention and conservation of tooth structure. The search continues for the identification of practical models for predicting caries risk at the individual level. This paper describes a method useful for targeting resources in sealant placement programs by enabling one to determine the relative effectiveness of sealing alternative tooth surfaces in the oral cavity. One guide serves as a widely adopted manual for those who use or intend to use dental sealants in caries prevention programs. This paper provides a brief review of that document, "Preventing Pit and Fissure Caries: A Guide to Sealant Use," as well as guidelines for sealant utilization provided by the American Dental Association, and information regarding dental sealant programs under Medicaid. The final portion of the paper provides a synthesis of the epidemiology reviewed and summarizes the implications of findings for sealant programs.

A longitudinal evaluation of fissure sealants applied in dental practices

Sealants are highly effective in preventing dental caries in the pits and fissures of teeth when applied by trained operators in clinical trials and public health programs. The effectiveness of fissure sealants when applied in dental practices is still not known. The purpose of this longitudinal study was to evaluate the effectiveness of fissure sealants applied in dental practices in preventing dental caries on occlusal surfaces of first permanent molars. In 1990, on the Island of Montréal, 911 randomly selected children, from 6 to 9 years of age, were examined; out of those, 816 and 733 were re-examined in 1991 and 1992, respectively. Only the 733 children with complete examination records were included in this evaluation. Sealant applications were either personally paid for or were paid for by private dental insurers. All children were covered for diagnosis and restorative care by a publicly financed and universal insurance program. Dental treatment records were provided by Quebec's health insurance board. In the epidemiological examination, the occlusal surfaces of first permanent molars, which are the only surfaces included in this analysis, were classified into: sound, non-cavitated and cavitated status, restored, and sealed. Sealants were evaluated for full or partial coverage of the occlusal surface and presence of dental caries. During the first and second years, 11.6% and 17.5% of the students had new sealants. The number of new sealants placed during the two years was 507. Children with caries-free status and whose parents had high school education or higher were significantly more likely to receive sealants during the study.(ABSTRACT TRUNCATED AT 250 WORDS)

Pit and fissure sealants: another major cornerstone in preventive dentistry

Despite dramatic reductions in caries in fluoridated communities, the disease continues to occur during childhood and adolescence and there is a sustained caries susceptibility of pits and fissures. Pit and fissure sealants have been available to the dental profession for the past two decades. Closely following community water fluoridation, this use of adhesive technology is now recognized as a major cornerstone of modern preventive dentistry. However, the technique appears to have been slow in implementation by the dental profession. Recent expanded utilization of sealants in the public sector, particularly in Victoria, has increased the awareness of the procedure amongst the public and is heightening demand. A review of the pertinent literature and current trends in utilization of sealants is presented. The case is made for expanded utilization of sealants in both the public and private sectors of dental health care delivery in Australia.

Effects of glass ionomer cement, resin-based pit and fissure sealant and HF applications on occlusal caries in a developing country field trial

The aim of this community-oriented study was to evaluate different methods to prevent fissure caries. The following products and measures were tested: 1) glass ionomer cement (GIC) applied by dentist; 2) same material applied by short term (3 days) trained personnel (teachers); 3) application of a 0.5% HF solution three times; 4) an established autopolymerized resin based sealant (Delton). The study was performed in Bangkok, Thailand, a city in a developing country experiencing increasing caries prevalence. Children with at least three sound permanent molars from two age groups, 7-8 and 12-13-yr-olds respectively were chosen from very low to medium socioeconomic level families. 1264 children were systematically assigned to experiment or control groups based on school and DMFT. For the younger age group, the 2 yr mean DFS occlusal increment in the Control group was 0.66 surfaces. Significantly lower increments were observed in the GIC experimental group: 0.17 surfaces applied by the teachers and 0.32 applied by dentist, corresponding to 74% and 52% reductions, respectively. The mean increment in the HF group was 0.44 surfaces, a 33% reduction in relation to the Control group. For the 12-13-yr-olds, the mean occlusal surface DF increment was 0.70 surfaces in the Control group. Almost no occlusal increment was found in the Delton group, 0.05 DFS, a 93% reduction. In the GIC Dentist group, the DFS increment was 0.48 and in the Teacher group 0.56, corresponding to 31% and 20% reduction, respectively. A slight and nonsignificant increase of caries in relation to the Control group was observed in the HF group.(ABSTRACT TRUNCATED AT 250 WORDS)

A comparison of dental caries experience in Native American and Caucasian children in Oklahoma

OBJECTIVES

In 1989 the Oklahoma Area Indian Health Service conducted an oral health survey of children attending public schools in Oklahoma to determine the extent of caries experience in the Native American population. Results were to be used to establish program priorities, gather baseline data, and compare the oral health status of Native American children with their non-Indian peers.

METHODS

A total of 934 elementary schoolchildren 5-6 years of age were examined along with 733 high school students 15-17 years of age. The study was designed so that approximately 50 percent of the students examined were Native American.

RESULTS

The mean dmfs for the 5-6-year-olds was 5.06 for the Caucasian children and 10.35 for the Native American children, a statistically significant difference (P < .001). For the 15-17-year-olds the mean DMFS for the Caucasian students (5.99) was significantly lower (P < .001) than the mean DMFS for the Native American students (10.12).

CONCLUSIONS

The prevalence and severity of caries in these Native American students appear to be substantially higher than in their non-Indian peers residing in the same communities. Further study is needed to identify factors contributing to these demonstrated differences in caries experience.

The prevalence of dental sealants in North Carolina schoolchildren

OBJECTIVES

This study reports the prevalence of dental sealants derived from a survey of schoolchildren in North Carolina, and its variation according to several sociodemographic characteristics.

METHODS

A single-stage, stratified probability sample of grade K-12 classrooms in the state yielded a sample of 8,026 students. Clinical examinations were performed on 83 percent of the sample. Estimates for sealant prevalence and their variation according to seven sociodemographic variables were determined.

RESULTS

About 117,000 children in the state, or 12 percent of those 6-17 years of age, have sealants. The prevalence of sealants varied according to geographic region of residence and the socioeconomic status of whites. Prevalence was affected little by age, sex, degree of urbanism, or socioeconomic status of those with races other than white.

CONCLUSIONS

While underutilized, there are indications in these data that sealant use is increasing, thus having the potential to contribute to further declines in the prevalence of dental caries in the state. Those factors included in this study and associated with the prevalence of sealants suggest that major gains in sealant use will need to address not only those specific barriers preventing their use by the profession or public, but broader issues preventing the utilization of dental services in general.

Evaluation of Guamanian dental caries preventive programs after 13 years

OBJECTIVE

To address the high prevalence of dental caries in Guamanian children, a school-based fluoride mouthrinse program, a clinic-based pit and fissure sealant program, and community water fluoridation were phased in over a 13-year period. The purpose of this paper is to evaluate the impact of these programs on the prevalence of dental caries.

METHODS

Cross-sectional samples representative of schoolchildren in grades 1 through 8 were selected in 1976, 1979, 1984, 1986, and 1989. These years include the starting years for each of the three interventions and varying follow-up periods for each. About 1,000 children in each of the survey years were examined to derive DMF surface scores.

RESULTS

After eight years of fluoride mouthrinsing, DMFS scores were reduced by 25.4 percent in 6-14-year-olds. With two additional years of fluoride mouthrinsing and with pit and fissure sealants, overall DMFS scores declined an additional 44.4 percent. In 1989, three years after community water fluoridation was initiated on the island and continuation of the other two programs, there was a further decline in overall DMFS scores of 34.5 percent. Over the entire study period--during which there were 13 years of fluoride mouthrinsing in the schools, five years of sealant application, and three years of community water fluoridation--DMFS scores declined 72.8 percent overall (5.14 surfaces per child) and 71.9, 71.0, and 78.8 percent for occlusal, buccal-lingual, and proximal surfaces, respectively.

CONCLUSIONS

An intensified preventive dentistry program introduced on an island with high caries prevalence twice that of the US mainland was successful, and contributed to a reduction in the prevalence of caries to a level equivalent to that of the United States at the end of the study period.

Research in dental health education and health promotion: a review of the literature

This article presents a review of research in dental health education and health promotion. In the period 1982 to 1992, a total of 57 studies evaluating the effectiveness of interventions to alter individuals' behavior related to dental health were identified. Combining the results of these 57 studies with descriptive articles published over the same period, it appears that dental health education can result in improvements in objective measures of dental health behaviors and actual oral health measures, but has only limited success in changing attitudes towards dental issues and achieves only short-term gains in knowledge. The limited use of theoretical frameworks, poor statistical analyses, the use of convenient samples and the short post-intervention follow-up periods diminish the contribution of this research to the development of dental health policy and the formation of strategies to improve the health of communities.

Dental caries in preschool Beijing and Connecticut children as described by a new caries analysis system

A total of 625 children, 3-4 yr old, 426 from Connecticut Head Start programs and 199 from Beijing area nursery schools, were clinically examined for dental caries. Results were analyzed using the traditional dmfs index as well as a new "Caries Analysis System". This new system differentiated between caries patterns and examined the percentage of affected children (Prevalence), the degree to which these children were affected (Severity) and the proportion of total caries each disease pattern represented (Distribution). The Caries Analysis System revealed differences in caries experience and patterns among the racial/ethnic groups that the dmfs index did not. The Beijing children experienced the greatest Prevalence of all caries patterns; however, the Severity and Distribution of the caries patterns were similar to those of the Connecticut children. Within the group of Connecticut children, White children had the lowest Prevalence but the greatest Severity when compared with the Black and Hispanic children.

Comparison of glass-ionomer and resin-based fissure sealants: a 2-year clinical trial

In recent years, the interest in the use of glass-ionomer materials as fissure sealants has increased. The aim of this study was to compare the retention and caries-preventive effect of glass-ionomer (Fuji III) and resin-based light-cured (Delton) fissure sealants. Three health center dentists applied the sealants to 166 children; glass-ionomer sealants on one side and resin-based sealants on the contralateral side of the mouth. After 2 yr, one pair of molar teeth in the mouths of 151 children was compared. Twenty-six percent of glass-ionomer and 82% of resin-based sealants were totally present (P < 0.001). During the 2 yr, in both groups 4.6% of the sealed surfaces became carious. The results show that the retention of glass-ionomer sealants is markedly inferior to the resin-based sealants. In this study, however, no difference in caries increment on the sealed surfaces was observed. This may be due to the different mechanism of caries prevention for the sealant materials, or to the overall low caries activity of the participants.

Occlusal dental caries incidence and implications for sealant programs in a US college student population

Given the decline in dental caries incidence in preteens and young teenagers in the United States, a study of the incidence of dental caries in young adults (17-23 years) was conducted to provide a descriptive epidemiologic picture of this "new" natural history of dental caries in the late and post-teenage years. A retrospective study was performed analyzing the detailed dental records of the four-year college experience in the class of 1989, US Coast Guard Academy. Occlusal caries incidence, in the absence of associated proximal caries, was shown to be moderately common in molars (11.9%) and rare in premolars (0.8%). In contrast to previous studies' findings, demographic indicators, socioeconomic status indicators, and prior caries experience were poor predictors of occlusal caries incidence; targeting a universal sealant policy in this population therefore would be done best by tooth type rather than patient type. A preliminary cost-comparison model, projected over a 40-month period, suggests that the cost of initiating a universal molar sealant policy in this population would be 92 cents per year per student greater than the cost of restoring occlusal caries in the presence of sound proximal surfaces. This cost comparison suggests that it would be advantageous to initiate such a policy.

Factors influencing the effectiveness of sealants--a meta-analysis

Meta-analysis of published studies was applied to analyze the effectiveness of fissure sealants in preventing dental caries. Studies were identified by a MEDLINE search, supplemented by a hand search of the references in the articles recovered. All articles were assessed on the basis of quality, and were combined with the Mantel-Haenszel method. The prevented fraction in the exposed population (PF) was estimated using pooled relative risk. Heterogeneity of the effect and publication bias were also analyzed. Twenty-four studies were included in the meta-analysis. The overall effectiveness of autopolymerized fissure sealants was 71.36% (95% confidence interval 69.69-72.94%). Effectiveness in preventing caries decreased with time, and increased when drinking water was fluoridated (82.69% vs 72.28%). Heterogeneity was significant in most cases, and was further studied with multiple linear regression analysis. It is concluded that autopolymerizing sealants should be used. More research is needed to compare the effectiveness of dental hygienists and dentists in applying sealants.