PubMed Health⌕ Search

Biomedical subjects

C Meller

Publications and source records attributed to C Meller.

7 recordsLinked to original sources
PubMed2006

A new in vivo method for measuring caries activity with a colorimeter.

The aim of this in vivo study was to assess the association between caries prevalence and changes in mineralization measured with a colorimeter (Color Compare CC 400, JENOPTIK, Jena, Germany). After a clinical examination (defs/DMFS, initial caries lesions), an area of a deciduous tooth was etched in each of the 35 children (psi = 8.11+/-2.41 years) with 37% phosphoric acid gel for 1 min. Immediately after, this demineralization was stained with 2% aqueous methylene blue and the red/green/blue spectrum measured with a colorimeter. Twenty-four hours later, the remineralization of this area was measured following the same staining procedure. Color measurements were clearly reduced after 24 h, indicating remineralization, and they correlated highly with the age of the children (Spearman correlation coefficient r = -0.48, p = 0.004). Correlations between the number of initial caries lesions in the deciduous and permanent dentition and color measurements after demineralization were statistically significant (r = 0.41 and 0.37, p = 0.02 and 0.045, respectively). The difference between the first and second measurements correlated significantly with the number of initial caries lesions in the permanent dentition (r = 0.42, p = 0.02). The values after artificial demineralization correlated with the number of initial lesions for the permanent (r = 0.368, p = 0.045) and deciduous (r = 0.408, p = 0.015) dentition. This resistance to artificial demineralization had stronger correlation coefficients with the caries incidence than the caries experience and initial lesions, which are considered to be the most valid caries predictors. In conclusion, these data suggest that the degree of demineralization after etching and its changes with time could be associated with caries parameters. Its use in prospective clinical trials on caries activity could be a successful approach.

Acid Etching, Dental↗
PubMed2006

A new in vivo method for measuring caries activity using quantitative light-induced fluorescence.

The aim of this in vivo study was to assess the association between caries prevalence and activity parameters and the properties of etched sites measured with quantitative light-induced fluorescence (QLF). In a clinical method, two areas of a deciduous tooth were etched in each of 44 children (mean age 8.23 years+/-1.45) with 36% phosphoric acid gel for 1 min and 4 min, respectively. DeltaQ of the etched site was measured immediately after the etching (DeltaQ1) and 24 h later (DeltaQ2) with QLF. In addition, deft/DMFT, approximal plaque (API), bleeding on probing (mod. PBI), active carious lesions and currently used fluorides were recorded. In a regression analysis for the deft, the use of fluoridated salt (standardized coefficient SC=-0.25) and fluoride gel (SC=-0.37) showed the greatest effect, as did the fluoride gel (SC=-0.26) and gingival bleeding (SC=0.50) for the number of active carious lesions. The deft and the number of active carious lesions correlated significantly (r=0.70, p<0.001). DeltaQ1 and DeltaQ2 showed a significant statistical correlation with the age-adjusted deft (0.39<r<0.52, p<0.01) and with the number of active lesions (0.42<r<0.59, p<0.01). Correlations between DeltaQ and the API, PBI and the fluoride scores were slightly weaker but also statistically significant. In a principal-component analysis, these parameters were approximately identical, indicating a strong relationship between the different variables and DeltaQ. This relationship was especially strong for the deft and the active carious lesion scores. In conclusion, these data suggest that the degree of demineralization by etching and its changes with time are associated with caries activity and that this method might be used for the early assessment of caries activity.

Child↗
PubMed2006

Effectiveness of sealants in adolescents with high and low caries experience.

The aim of this 3-year longitudinal study was to analyze caries increment and the caries-preventive effect of sealants in adolescents in the setting of the German national health system. 434 pupils (193 male, 241 female) took part in compulsory school examinations at age 12 (mean 12.3 +/- 0.4 years) and 15 (mean 15.6 +/- 0.3 years) according to WHO criteria, including the examination of sealants. Mean DMFT increased from 1.78 (+/- 2.15) to 3.97 (+/- 3.68), mean DMFS from 2.79 (+/-4.07) to 6.94 DMFS (+/- 8.34), respectively. Logistic regression analysis showed that high caries incidence at the individual level was mostly associated with the type of school ('Gymnasium', RR = 0.3), gender (female, RR = 2.08) and high baseline DMFS (RR = 1.2 per surface), but not with the number of sealants. In an interaction model, adolescents with high baseline DMFS values had an even higher risk of caries increment with an increasing number of sealants compared to adolescents with fewer sealants (p = 0.047). At the tooth level, this effect was detected for first permanent molars, while sealants in premolars and second permanent molars did not result in a statistically significant caries-preventive effect due to the low caries incidence on these surfaces. Thus, sealants on occlusal surfaces of first permanent molars were only protective in individuals with low or moderate caries activity (p = 0.006), which indicates the need for other measures to reduce caries activity in high risk adolescents. In addition, rates of 19% lost sealants and 18% carious or filled surfaces in 3 years suggest a discrepancy between sealant retention under real-life conditions and the results of controlled clinical trials.

Adolescent↗
PubMed2006

Chemo-mechanical dentine caries removal with Carisolv using a rotating brush.

AIM: The aim of this study was to assess the efficacy of removing dentine caries using carbide burs, Carisolv with hand instruments and Carisolv in combination with a new mechanical excavation method using a rotating brush. METHODS: 36 extracted permanent teeth, with dentine caries, were assigned into 3 groups according to caries removal technique. Caries removal was monitored by checking the properties of the dentine with a dental explorer. After embedding and sectioning (400 microm), remaining caries was assessed by using a caries detector. In microscope images (7x) of the samples, the mean stain depth of the remaining carious tissue per tooth was calculated by AnalySIS computer software. RESULTS: Four to 8 applications (mean time = 10.9 min) of Carisolv were necessary for caries removal with the new method using rotating brushes. The mean thickness of residual dentine caries by this procedure (226 microm, +/- 136) was higher than the one using Carisolv with hand instruments (57 microm, +/- 39) or carbide burs (32 microm, +/- 20). Even in areas with good access to the lesion, an unacceptable amount of residual caries was observed. CONCLUSION: Thus, it seems that Carisolv using rotating brushes does not reach the degree of caries removal reached by additional mechanical abrasion of Carisolv using hand instruments or conventional rotating carbide burs.

Coloring Agents↗
PubMed1990

[Study of cellular immunity in patients with Mediterranean visceral leishmaniasis].

Cellular immunity against Leishmania infantum antigens was studied in visceral leishmaniasis patients and healthy subjects living in a endemic area. Only the healthy subjects were TTL positive with production of gamma interferon, whereas the visceral leishmaniasis patients presented a transitory inhibition of their specific cellular response mechanisms.

Adult↗