Biomedical subjects

C Splieth

Publications and source records attributed to C Splieth.

14 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↗

PubMed2005

German dental faculty attitudes towards computer-assisted learning and their correlation with personal and professional profiles.

BACKGROUND: Compared with its potential, computer technology use is still lacking in medical/dental education. OBJECTIVES: To investigate the primary advantages of computer-assisted learning (CAL) systems in German dental education, as well as the reasons for their relatively low degree of use correlated with personal and professional profiles of respondents. METHOD: A questionnaire was mailed to heads in the departments of conservative dentistry and prosthetic dentistry in all dental schools in Germany. Besides investigating the advantages and barriers to the use of computer technology, the questionnaire also contained questions regarding each respondent's gender, age, academic rank, experience in academia and computer skills. RESULTS: The response rate to the questionnaire was 90% (112 of 125). The results indicated a distinct discrepancy between the desire for and actual occurrence of lectures, seminars, etc. to instruct students in ways to search for and acquire knowledge, especially using computer technology. The highest-ranked advantages of CAL systems in order, as seen by respondents, were the possibilities for individual learning, increased motivation, and both objective theoretical tests and practical tests. The highest-ranked reasons for the low degree of usage of CAL systems in order were the inability to finance, followed equally by a lack of studies of CAL and poor cost-advantage ratio, and too much effort required to integrate CAL into the curriculum. Moreover, the higher the computer skills of the respondents, the more they noted insufficient quality of CAL systems (r = 0.200, P = 0.035) and content differences from their own dental faculty's expert opinions (r = 0.228, P = 0.016) as reasons for low use. CONCLUSION: The correlations of the attitudes towards CAL with the personal and professional profiles showed not only statistical significant reinforcements of, but also interesting deviations from, the average responses.

Adult↗

PubMed2004

DentSim - a future teaching option for dentists.

Apart from a requirement to acquire more and more academic knowledge, during their training, dental students need to acquire a full range of highly precise manual and technical skills, including excellent hand/eye coordination, to enable them to visualize and understand how to prepare cavities, prior to placing restorations. Furthermore, unlike medical students, dental students are in the position of administering treatment to patients very early in their training. The increasing academic workload means that these skills have to be mastered in a short space of time. This you will gain in the future only through the use of effective methods of the educations - for example by the use of the computer-assisted dental simulators (DentSim/DenX), which serves the visual-, audio- and practical learning channel simultaneously. Unlike the conventional phantom heads, the DentSim-unit has the following advantages - the acquisition of knowledge takes place in a multimedia learning environment with a high audio-visual content and degree of interaction and complexity, - problem-oriented learning takes place through clinically relevant work, - individual students can work to personalized programs through the digital tutor function, - two-dimensional knowledge is transferred into three-dimensional spatial work, - three-dimensional preparations can be easily analysed by two-dimensional error analysis, - all preparation exercises are recorded for error and effectiveness analysis. Apart from student training, the computer-assisted simulators can also be used for the evaluation of the effectiveness or the quality control of various teaching methods in the context of Evidence Based Dental Education.

Computer Simulation↗

PubMed2002

Polymerization shrinkage-strain and microleakage in dentin-bordered cavities of chemically and light-cured restorative materials.

OBJECTIVES: The aim of this study was to evaluate in vitro the relationship between polymerization shrinkage and microleakage in dentin-bordered restorations. METHODS: Four light-cured restorative materials in combination with their respective dental bonding agents (DBA) were investigated: Tetric Ceram/Syntac classic (Vivadent), Solitaire/Gluma Solid bond (Heraeus Kulzer), Definite/Etch & Prime 3.0 (Degussa), Solitaire 2/Gluma Solid bond (Heraeus Kulzer). The chemically cured resin Degufill sc microhybrid (Degussa) in combination with ART Bond (Coltène) was also included. Polymerization shrinkage of the restorative materials was measured using three different methods (dilatometer, linometer, buoyancy method) and analyzed with ANOVA. For the determination of microleakage, caries-free human molars were embedded in acrylic resin and subsequently abraded with a wet abrasion machine to produce four level dentin surfaces. One hundred sixty cavities (3 mm diameter/1.5 mm deep) were randomly assigned to four groups of equal size. The groups were restored without (group 1 and 2) and with DBA (group 3 and 4), and either not subjected (group 1 and 3) or subjected (group 2 and 4) to 2000 cycles from 5-55 degrees C. Each group was further divided into five material subgroups of eight cavities each. Microleakage was determined using a dye penetration test assessed at depths of 200, 400 and 600 microm into the fillings. Data were analyzed with the Kruskal-Wallis and the Mann-Whitney test. RESULTS: All three methods of measuring polymerization shrinkage (PS) generated the same, statistically secured ranking for the four light-cured restorative materials: PS Definite < PS Tetric Ceram < PS Solitaire 2 < PS Solitaire. In the microleakage study, only a few statistically significant differences were observed. Etch & Prime 3.0/Definite in group 3 and Solid Bond/Solitaire 2 in group 4 tended to exhibit the least microleakage. Correlation coefficients between aggregated shrinkage and microleakage data were 0.3 for group 3 and -0.2 for group 4. SIGNIFICANCE: The results do not suggest any correlation between polymerization shrinkage and microleakage in dentin of direct adhesive restorations.

Analysis of Variance↗

PubMed2002

Caries experience and treatment response among groups of Finnish, German and Russian children. A retrospective study between 1995 and 1989.

AIM: This study was designed to describe caries experience and treatment response in groups of children in three countries--Finland, Germany and Russia--with different systems of public dental care. MATERIALS AND METHODS: Information concerning permanent teeth (carious and filled surfaces, type of restorative treatment and applied sealants) was collected retrospectively from existing dental records of 12-year-old children who had been treated in dental practices over six years, retrospectively between 1995 and 1989. Prior to conducting the study, research meetings were held among all participating personnel to standardise data collection and terminology as much as possible. STATISTICS: The analysis of variance (ANOVA) was used to test the difference between the means of the various types of data derived from the three countries. RESULTS: Sealants were most commonly used in Finland at a rate of 5.0/child and 3.3 in Germany, but only for a few children in Russia (0.1). Caries increments (cumulative figure of primary and secondary caries surfaces over the six follow-up years of the study) differed very much between these countries. It was very high in Russia (7.4) and in Germany (5.3), but low in Finland (1.6). All the caries surfaces were filled in Finland and in Germany; in Russia, the cumulated number of filled surfaces was smaller than the respective number of caries surfaces (6.4/7.4). The most commonly used restorative filling material was amalgam in Germany and in Russia, but composite or glass ionomer cements in Finland. CONCLUSION: The cost effectiveness of sealant application programs should be considered as exemplified by the Finnish dental care system. The data showed a need for preventive programs in Germany, and this has actually been emphasised since 1993. In Russia, there is an urgent need to implement preventive programs for 6-year-old children and also to provide the necessary restorative treatment.

Journal Article↗

PubMed2001

Determination of residual dentine caries after conventional mechanical and chemomechanical caries removal with Carisolv.

The aim of the study was to assess the efficacy of removing dentine caries chemomechanically with Carisolv and with round burs. In 24 extracted permanent teeth each, caries removal with Carisolv or rotating round burs was monitored by checking the hardness of the dentine with a dental explorer and stopped at 12 teeth in each group when either (a) a leather-hard texture was reached or (b) a sharp scratching sound was heard. After embedding and sectioning (400 microm), caries activity of the remaining dentine was assessed using methyl red dye. In microscope images (7x) of the samples, the mean depth of the pink (caries-active, pH<5.5) and yellow (pH>5.5) staining of each carious lesion was calculated. Using a round bur, the depth of caries-active and -inactive lesions was significantly greater when a leather-hard texture (51-58 microm) was reached than when a sharp scratching sound was reached (19-25 microm, t-test, P<0.05). For teeth treated with Carisolv, only the depth of the caries-inactive dentine differed significantly. Regardless of the clinical criterion for caries removal, Carisolv treatment resulted in higher mean depths of caries-active dentine (71-78 microm) than conventional caries removal using the round bur (19-51 microm), while the mean depths of the caries-inactive dentine differed minimally. Thus, caries removal with Carisolv leaves up to a mean of 50 microm more carious dentine than round burs.

Azo Compounds↗

PubMed2000

Effect of cement type on retention of a tapered post with a self-cutting double thread.

OBJECTIVES: The aim of this in vitro study was to examine the effect of varying the cement type on the retention of a prefabricated tapered titanium post with a self-cutting double thread (Perma-tex activ). METHODS: A total of 130 suitable roots from extracted human permanent teeth were selected. Post holes were prepared using the instruments supplied with the post system. One-hundred-twenty posts (medium size) were luted with one of four luting agents: a zinc-phosphate cement (Harvard), a glass-ionomer cement (Ketac Cem), a compomer luting agent (Dyract Cem), and a new capsulated composite luting system (Compolute). The cement groups were subdivided into three treatment groups with 10 posts each: group 1 (4-week water storage at 37 degrees C), group 2 (4-week water storage at 37 degrees C, 4000 cycles 5-55 degrees C), group 3 (4-week water storage at 37 degrees C, 4000 cycles 5-55 degrees C, 3 x 4 min mechanical stress: 40N vibrations). Another 10 posts inserted without cement and stored like group 1 served as a control. Retention was measured on a universal testing machine (Zwick Z050/TH3A) with a crosshead speed of 0.1cm/min. Data were analyzed using ANOVA with a Bonferroni or Tamhane adjustment for multiple comparisons (significance level alpha=0.05). RESULTS: In group 1, Dyract Cem was significantly more retentive than the other three cements and the control group (no cement). In group 2, Compolute demonstrated significantly higher retention than Harvard and Ketac Cem. In group 3, Compolute, Dyract Cem, and Ketac Cem obtained higher retentive values than Harvard without differing from one another. Within the cement groups, thermocycling (group 2) caused a significant decrease in retention compared to group 1 only for Dyract Cem. All cements except Compolute were different from group 1 after a combination of thermocycling and mechanical stress (group 3). CONCLUSIONS: The retention of the tapered post with a self-cutting double thread was significantly influenced by the cement type used.

Analysis of Variance↗

PubMed2000

Caries prevention with chlorhexidine-thymol varnish in high risk schoolchildren.

In a prospective, randomised and blinded cohort study, the acceptance and effectiveness of a 3-monthly chlorhexidine-thymol varnish application was assessed in 8- to 10-yr-old children (n=29) with high caries incidence after brushing with a 1.23% fluoride gel. The children of the control group (n=25) brushed with a fluoride gel only. The standardised interview showed good acceptance of the varnish applications in spite of the bitter taste. Caries incidence in one year was 1.2 DMFS (SD 1.5, median 1; 95% confidence interval 0-1) for the test group and 2.1 DMFS (SD 2.3, median 2; 95% confidence interval 0-3) for the control group. Due to a slightly lower reduction in caries incidence (42.3%) than in other studies and a higher standard deviation than in unselected study groups, the power of the present study was not high enough to prove this difference in caries incidence to be statistically significant in the Mann-Whitney test (P=0.11). This was also found for the difference of 0.4 initial lesions. The distribution patterns of caries incidence for tooth groups (70% in the first permanent molar) and surfaces (58% on occlusal surfaces) did not differ between the test and the control group. The reductions of caries incidence which have been found in highly caries active children of the present study should be evaluated further with a larger study sample.

Anti-Infective Agents, Local↗

PubMed2000

Prophylactic and therapeutic application of antimicrobial agents in the oral cavity.

Antimicrobial substances are used for many prophylactic and therapeutic reasons in the oral cavity. They are used as mouthrinses, for the irrigation of specific oral locations, in form of gels, or varnishes. Different antimicrobial agents are available and some preparations are complex compositions of these compounds. Although it has been proven that several agents are suited to achieve a considerable reduction of oral microorganisms many questions concerning the clinical benefit are yet to be answered. This report summarises the evidence of the efficacy of oral antiseptics (especially chlorhexidine, pvp-iodine, and Listerine) depending on different indications, which is the basis for clinical and practical recommendations.

Anti-Infective Agents↗

PubMed1999

Activities of lysozyme and salivary peroxidase in unstimulated whole saliva in relation to plaque and gingivitis scores in healthy young males.

The purpose of the present investigation was to study the suitability of the salivary activity of lysozyme and salivary peroxidase for monitoring the inflammatory state of the gingiva. Salivary peroxidase and lysozyme activities in resting whole saliva were measured in a group of 140 male subjects (aged 18-30 years). A full mouth, clinical assessment of the plaque index (PI) and the sulcus bleeding index (SBI) was made and gingival crevicular fluid (GCF) flow was measured at teeth 16, 12, 24, 36, 32 and 44 with the Periotron 6000. There were no significant differences in the mean values of lysozyme and salivary peroxidase activities between groups with different PI, SBI and GCF flow values. Statistically significant correlations were found among the clinical parameters, with SBI and PI showing the strongest relation (r = 0.47). The correlation between GCF flow and PI was higher (r = 0.43) than the correlation between GCF flow and SBI (r = 0.20). However, there were no statistically significant correlations between the activities of salivary peroxide and lysozyme and the clinical measures of gingival health.

Adolescent↗

PubMed1999

Prediction of caries development for molar fissures with semiquantitative mutans streptococci test.

Risk-specific caries prevention requires validated and simple parameters for a caries risk assessment. The aim of the study was to evaluate the validity of a site-specific chair-side mutans streptococci (MS) test for the prediction of caries incidence in fissures. In 230 6- to 7-yr-old children, occlusal plaque samples of teeth 16 and 36 were cultured with Dentocult SM tests at 37 degrees C for 24 hr. Caries (DMFS), initial caries, sealants, and a plaque index (QHI) were recorded and oral hygiene habits were assessed. Not erupted, carious, filled and sealed teeth were excluded from the analysis (n = 154). After 2 yr, the status of the fissures was re-examined, and a fluoride history was recorded with a questionnaire filled out by the children's parents. Sealed teeth were excluded again (n = 54). With a classification of MS score 0 or 1 as low and MS score 2 or 3 as high caries risk, 92% agreement was reached by two independently working examiners. The MS scores and caries incidence correlated significantly. Seventy-eight % of the caries progression in fissures was prognosed correctly. Sensitivity was 50%, specificity 82%, positive predictive value 29%, and negative predictive value 92%. Children with caries progression tended to have lower fluoride scores. Low MS scores were most likely to be associated with low caries incidence, while high mutans streptococci scores seem to be partially compensated by other parameters.

Cariostatic Agents↗

PubMed1996

Factors for changes of caries prevalence among adolescents in Germany.

Data on caries prevalence among adolescents in East and West Germany before and after unification (1990) were compared with changes in etiologic and preventive parameters. The postwar increase of total sugar consumption resulted in an increase of caries prevalence among adolescents in both East and West Germany until 1970. Parallel to the introduction of preventive measures, especially systemic fluoridation, the national caries level in East Germany stabilized at 4-5 DMFT (in 13-14-year-olds) with significant regional differences. The introduction of fluoridated toothpaste after 1973 in West Germany was followed by a caries decline in children (1970s) and in adolescents (1980s) from very high caries levels (8.8 DMFT in 13-14-year-olds in 1983) to moderate levels (5.1 DMFT in 1989). The sudden increase from 10% to 90% fluoridated toothpaste in East Germany in 1990 was also accompanied by a caries decline in adolescents. Group prevention, which included fluoride varnish programs and the introduction of free prevention (brushing instructions, fluoridations, sealants) at private dentists for 6-19-year-olds since 1983, seems to be responsible for the latest caries reductions all over Germany.

Adolescent↗

PubMed1993

Retaining sealant on salivary contaminated enamel.

A two-year clinical study comparing sealants done with intentional salivary contamination shows that sealant retention is possible on wet enamel if a bonding agent is used between enamel and sealant. Dental material research implications and clinical possibilities are discussed.

Adolescent↗