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L Seppä

Publications and source records attributed to L Seppä.

70 records · Page 4Linked to original sources

Three-year report on caries prevention of using fluoride varnishes for caries risk children in a community with fluoridated water.

The benefit of semiannual application of the sodium fluoride varnish Duraphat and the silane fluoride varnish Fluor Protection was studied in 11--13-year-old children with high caries activity and life-long exposure to fluoridated drinking water (1--1.2 parts/10(6)). Annual clinical and radiographic examinations were made of 62 children in the Duraphat group and 70 children in the Fluor Protector group. Fluoride varnish was applied semiannually using the half-mouth technique. After 3 years, for the Duraphat group mean total DMFS increments on the control side were 6.2 and on the test side 4.3 (P less than 0.001); for the Fluor Protector group the DMFS increments were 4.9 and 4.4, respectively (NS). The caries reductions were 30% and 11%. Since there were no differences between initial mean DMFS scores of the groups, it is possible that the increment in the Fluor Protector control side compared to the Duraphat control side was due to fluoride ions from Fluor Protector crossing the midline and providing protection on the control side as well. Therefore, we conclude that Duraphat proved effective, but definite conclusion of the effect of Fluor Protector cannot be made. Children with the highest DMFS increment on the control side (Duraphat) gained most from the applications.

Adolescent↗

A 2-year report on caries prevention by fluoride varnishes in a community with fluoridated water.

The benefit of semi-annual applications of sodium fluoride varnish (Duraphat) and silane fluoride varnish (Fluor Protector) was studied in 11-13 year-old children with life-long exposure to fluoridated drinking water (1-1.2 parts/10(6)). Annual clinical and radiographic examinations were made on 67 children in the Duraphat group and 71 children in the Fluor Protector group. Fluoride varnish was applied semi-annually using the half-mouth technique. At the end of 2 years, the mean overall DMFS-increments on the control side and test side of the Duraphat group were 5.0 and 3.8 (p less than 0.01), respectively, and of the Fluor Protector group 3.7 and 3.3 (NS). The caries reductions were 24% and 12%, respectively. Since there were no differences between initial mean DMFS scores of the groups, it was assumed that lower increments in the Fluor Protector group were due to Fluoride ions crossing the midline and providing protection on the control side as well. When increments in the Duraphat control side and the Fluor Protector test side were compared, the caries reduction of Fluor Protector was 35% (p less than 0.01). Fluoride varnishes provide additional benefit even when fluoride intake from drinking water is optimal.

Adolescent↗

Caries trends 1992-1998 in two low-fluoride Finnish towns formerly with and without fluoridation.

Water fluoridation in Kuopio, Finland, was stopped at the end of 1992. In our previous study, no increase in caries was found in Kuopio 3 years after the discontinuation of water fluoridation. The aim of the present study was to further observe the occurrence and distribution of caries in Kuopio and Jyväskylä, which was used as the reference town for Kuopio. In 1992, 1995 and 1998 independent random samples of all children aged 3, 6, 9, 12 and 15 years were drawn in Kuopio and Jyväskylä. The total numbers of subjects examined were 688, 1,484 and 1,530 in 1992, 1995 and 1998, respectively. Calibrated dentists registered caries clinically and radiographically. No indication of increasing caries could be found in the previously fluoridated town during 1992-1998. In both towns the mean dmfs and DMFS values either decreased or remained about the same during the observation period. When all study years and both towns were pooled, 25% of the 12- and 15-year-olds with the highest DMFS counts accounted for 79 and 67%, respectively, of all affected surfaces. The mean numbers of fluoride varnish and sealant applications had markedly decreased in 1993-1998 compared to 1990-1992. The fact that no increase in caries was found in Kuopio despite discontinuation of water fluoridation and decrease in preventive procedures suggests that not all of these measures were necessary for each child.

Adolescent↗

Caries data collected from public health records compared with data based on examinations by trained examiners.

Collecting data for dental caries studies is costly. In countries where uniform patient records are available for virtually the whole population, it is tempting to use them as a data source. Our aim was to compare data collected from patient records to those obtained by trained examiners. In 1992 and 1995, dentists who were specially trained and calibrated examined random samples of 12- and 15-year-olds living in two towns in Finland. The dental record of each child was obtained from public dental clinics, the dental status was entered into a computer file, and the DMFS value was calculated. Data were available for 824 children. In the two data sets, 1.3% of the tooth surfaces were recorded differently (DMF vs. sound) with the related kappa value being 0.70. In two thirds of the discrepancies, the reason was that a filling was marked in only one of them, which confirms the known difficulty in discerning a white filling. For 48% of the subjects, the DMFS values calculated from the two sets of data were equal. The difference was 1 and 2 surfaces for 28 and 11%, respectively. Public health dentists had almost equally often registered more and less DMF surfaces compared to trained examiners. The results suggest that data collected from public health records are not decisively inferior to those obtained from examinations by trained examiners. In large enough settings, data obtained from patient records could possibly be used as a replacement for separate surveys.

Adolescent↗

Caries occurrence in a fluoridated and a nonfluoridated town in Finland: a retrospective study using longitudinal data from public dental records.

The tap water of Kuopio, Finland, was fluoridated from 1959 to 1992. In the first decade of fluoridation, children in Kuopio had lower DMF values than children in Jyväskylä, a nearby low-fluoride town, but later differences between the towns have been small and inconsistent. The present study aimed to gain further insight into caries occurrence in Kuopio and Jyväskylä using longitudinal tooth-specific data from public health records on cohorts born in 1970/71 and 1980/81 (total n = 1,503). Survival analyses were used to summarize the tooth-specific times elapsed between eruption and the first filling (used as a proxy for dental caries). Generally, the first filling was placed sooner after eruption in the 1970/71 cohort than in the 1980/81 cohort. The curves for the two towns were virtually identical except for the first molars of the 1970/71 cohort, for which the percentage of filled first molars was consistently lower in Jyväskylä than in Kuopio. This study indicates that, among children and adolescents whose permanent teeth erupted in the mid-1970s or thereafter, even a longitudinal approach did not reveal a lower caries occurrence in the fluoridated than in the low-fluoride reference community. The main reason for the modest effect of water fluoridation in Finnish circumstances is probably the widespread use of other measures for caries prevention. The children have been exposed to such intense efforts to increase tooth resistance that the effect of water fluoridation does not show up any more. The results must not be extrapolated to countries with less intensive preventive dental care.

Adolescent↗

Clinical study of the use of the laser fluorescence device DIAGNOdent for detection of occlusal caries in children.

Diagnosis of non-cavitated occlusal caries is generally considered problematic. The aim of this study was to evaluate the utility of the laser fluorescence device DIAGNOdent as part of routine dental check-ups in children. A total of 613 occlusal surfaces on permanent molars and 436 surfaces on primary molars in children aged 7-8 (n = 55) and 13-14 years (n = 54) were examined visually, using DIAGNOdent and for most 13- to 14-year-olds also using radiographs. The teeth were not cleaned professionally before examination. To provide a gold standard for carious teeth, the depth of the caries lesion was determined in those lesions that were judged visually to need opening by drilling (51 teeth). The higher the visual score, the higher were the mean DIAGNOdent values, but in each visual category the variation among values was large. The presence of a clear sealant did not affect DIAGNOdent measurements. The values for permanent and primary molars differed slightly. For permanent teeth, Youden's index value was highest (60%) at a cut-off value of 30, which indicates that the overall performance for DIAGNOdent in detecting dentinal caries was best at this point. Using this cut-off, sensitivity was 92% and specificity 69% with visual examination for validation, while sensitivity was 92% and specificity 82% with validation by fissure opening. Of the three methods, radiographic examination was the least accurate. In routine dental check-ups of children, DIAGNOdent appears to be useful as an adjunct to visual examination.

Adolescent↗

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.

Adolescent↗

Resistance of occlusal fissures to demineralization after loss of glass ionomer sealants in vitro.

Seventy-one caries-free human occlusal fissures were used for this study. Twenty-two fissures were sealed with a glass ionomer sealant (Fuji Ionomer Type III--G-C Dental Industrial Corp., Tokyo, Japan), 24 were widened with a diamond bur and sealed with the glass ionomer sealant, and 25 were left unsealed. After one week, the sealants were removed as completely as possible with a probe. All fissures were demineralized for seven weeks. Sections made from the fissures were examined with a polarizing microscope, and the depths of the fissure lesions were measured. The mean lesion depths for controls, sealed natural fissures, and sealed widened fissures were 143, 93, and 75 microns, respectively. A statistically significant difference was noted between the two experimental groups and the control group (no sealant). The results suggest that fissures sealed with glass ionomer are more resistant to demineralization than control fissures, even after macroscopic sealant loss. This may be the result of the combined effect of fluoride released by glass ionomer and residual material in the bottom of the fissures.

Bicuspid↗