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Purpose: The aim of this study was to evaluate the cleaning efficacy of interdental brushes with different stiffnesses, e.g. soft and hard interdental brushes with identical brush diameter.Materials and Methods: Cylindrical soft and hard interdental brushes with diameters of 2,3 and 5 mm each were tested. Sixteen extracted human molars were fixed in split cast models to simulate eight interdental spaces. After coating the teeth with a dye to simulate plaque, digital photographs were taken from the proximal surfaces in a highly standardised set-up. The teeth were repositioned and the proximal surfaces were cleaned in a standardised manner. Post-brushing digital photographs were taken as before. After digital subtraction, the cleaned area was measured by pixel count and the relative cleaning efficacy was calculated.Results: The cleaning efficacy values of soft and hard interdental brushes of corresponding size in extra-small, small, medium and large interdental spaces as well as overall showed no statistically significant difference. In small, medium and large interdental spaces, increasing brush diameters resulted in higher cleaning efficacy; these differences were statistically significant. Irregular values were seen in extra-small interdental spaces.Conclusion: Both hard and soft interdental brushes cleaned the proximal tooth surfaces effectively. The filament stiffness had no statistically significant influence on the cleaning efficacy. [ABSTRACT FROM AUTHOR]

One-step incomplete excavation seals caries-affected dentin under a restoration and appears to be advantageous in the treatment of deep lesions. However, it is impossible to discriminate radiographically between intentionally left, arrested lesions and overlooked or active lesions. This diagnostic uncertainty decreases the acceptance of minimally invasive excavation and might lead to unnecessary re-treatment of incompletely excavated teeth. Radiopaque tagging of sealed lesions might mask arrested lesions and assist in discrimination from progressing lesions. Therefore, we microradiographically screened 4 substances (SnCl2, AgNO3, CsF, CsCH3COO) for their effect on artificial lesions. Since water-dissolved tin chloride (SnCl2×Aq) was found to stably mask artificial lesions, we then investigated its radiographic effects on progressing lesions. Natural lesions were incompletely excavated and radiopaque tagging performed. Grey-value differences (△GV) between sound and carious dentin were determined and radiographs assessed by 20 dentists. While radiographic effects of SnCl2×Aq were stable for non-progressing lesions, they significantly decreased during a second demineralization (p < .001, t test). For natural lesions, tagging with SnCl2×Aq significantly reduced △GV (p < .001, Wilcoxon). Tagged lesions were detected significantly less often than untagged lesions (p < .001). SnCl2×Aq was suitable to mask caries-affected dentin and discriminate between arrested and progressing lesions in vitro. Radiopaque tagging could resolve diagnostic uncertainties associated with incomplete excavation. [ABSTRACT FROM AUTHOR]

Objective: The purpose of this study was to compare proximal contact tightness (PCT) of MOD resin composite restorations placed with different matricing protocols. Methods: Forty-five ivorine lower right first molars with standardized MOD cavities were equally divided into three groups according to the restoration protocol. Group 1: Sectional matrix (Standard matrix, Palodent, Dentsply) secured with a wedge (Premier Dental Products Co.) and separation ring (BiTine I, Palodent, Dentsply, York, PA, USA) was used to restore the mesial surface first and then removed and repeated for the distal surface. Group 2: Identical to group 1, but separation rings were placed at both the mesial and distal sides (BiTine I+II, Palodent) prior to restoration. Mesial surface was restored followed by distal. Group 3: Walser matrix (O-form, Dr. Walser Dental GmbH) was used. Following composite resin restoration, PCT was measured using the tooth pressure meter. Data were analyzed using analysis of variance and a Tukey post hoc test (p<0.05). Results: PCT values for mesial contacts were 2.99 ± 0.47N for group 1, 4.57 ± 0.36N for group 2, and 3.03 ± 0.79N for group 3. For the distal contacts, the values were 4.46 ± 0.44N for group 1, 5.12 ± 0.13N for group 2, and 0.76 ± 0.77N for group 3. Significantly tighter contacts were obtained for mesial and distal contacts for group 2 compared to groups 1 and 3 (p<0.05). For groups 1 and 3, mesial contacts were not significantly different (p=0.993), while distal contacts for group 1 were significantly tighter (p<0.001). Conclusion: Within the limitations of this study, tighter contacts can be obtained when sectional matrices and separation rings are applied to both proximal surfaces prior to placement of the resin composite in MOD cavities. [ABSTRACT FROM AUTHOR]

Objectives: The aim of this exploratory double-blinded, randomized, cross-over, in situ study was to compare the effects of various model parameters ('intervention', 'brushing', 'position') on enamel caries lesions in a dose-response model.Methods: In each of four experimental legs of four weeks 16 participants wore intraoral mandibular appliances with four 'plaque-retaining' and four 'easily cleanable' positioned pre-demineralized bovine enamel specimens in the vestibular flanges mimicking proximal and buccal surfaces, respectively (n=512). The four randomly allocated interventions (either application only or brushing) included the following dentifrices: AlF3 1360ppmF(-)+chlorhexidine 0.05% (Lacalut aktiv, LA1360), NaF 1,450ppmF(-)(Blend-a-Med ProExpert), NaF 500ppm F(-) and 0ppm F(-) as negative control (NC) (both experimental, based on Blend-a-Med ProExpert).Results: Differences in integrated mineral loss (ΔΔZ) and lesion depth (ΔLD) were calculated between values before and after the in situ period using transversal microradiography. Significant differences for ΔΔZ [adjusted mean (95% CI))] were found between NC, NaF500 and LA1360for both 'plaque-retaining' [-1830 (-2371;1289); -986 (-1530;442); -2 (-548;544)vol%×μm] as well as 'easily cleanable' specimens [-399 (-682; -116); -391 (-672; -110); -16 (-302;270)vol%×μm]. Values for NaF1450 revealed a similar dose-response as LA1360.Values for LA1360 and NaF1450 did not differ significantly (p>0.05; ANCOVA).Conclusion/clinical Significance: The design of the present in situ study was able to reveal a fluoride dose-response to hamper further demineralization of enamel specimens for 'easily cleanable' and 'plaque-retaining' sites being brushed or not. Particularly 'plaque-retaining' sites seem to be recommendable for measuring potential anticaries efficacy in situ. [ABSTRACT FROM AUTHOR]

Objectives: The aim of this in vitro study was to evaluate the penetration of an infiltrant and a sealant, when applied as recommended, into fissure caries lesions. Methods: The fissure systems of extracted human teeth were classified according to the international caries detection and assessment system (ICDAS, codes: 0, 1, 2). Within each ICDAS-code ten teeth were either etched with 37% H3PO4-gel for 60 s and subsequently sealed ('Fissure Sealing'; Helioseal; Ivoclar Vivadent) or etched with 15% HCl-gel for 120 s and subsequently infiltrated ('Resin Infiltration'; Icon; DMG). Additionally, ten teeth with ICDAS-code 2 were etched with 37% H3PO4-gel for 120 s and infiltrated ('Soft-Etch-Infiltra- tion'). Specimens were cut perpendicular to their surfaces, polished, and confocal microscopic images were obtained. Lesion depths (LDmax) and penetration depths (PDmax) were measured and percentage penetration was calculated as PPmax = PDmax/LDmax ╳ 100. Results: Baseline LDmax [median (interquartile range)] for ICDAS-code 2 lesions was 1192 (805-1512) μm. In ICDAS-code 2 lesions PPmax was significantly higher for specimens treated with 'Resin Infiltration' [41 (30-78)%] compared to 'Soft-Etch-Infiltration' [11 (0-21)%] or 'Fissure Sealing' [5 (0-9)%] ( p < 0.05; Mann-Whitney test). PPmax did not differ significantly between groups in ICDAS-code 0 and 1 lesions ( p > 0.05) Conclusion: The fissure sealant when applied after etching with H3PO4-gel only penetrates superficially into non-cavitated fissure caries lesions. Penetration of an infiltrant is superior in particular after etching with HCl-gel. Clinical significance: Compared with sealing, infiltration of fissure caries lesions leads to more deeply infiltrated lesions, which might in turn result in superior abilities to hamper caries progression. [ABSTRACT FROM AUTHOR]

Objectives: The purpose of the study was to evaluate the effect on dental plaque and gingivitis of a dentifrice without sodium lauryl sulphate (SLS) compared to two SLS-containing dentifrices., Material and Methods: For this double-blind, parallel study, 90 volunteers having moderate gingival inflammation (≥40%) were randomly divided among three groups: one group using non-SLS dentifrice containing enzymes, colostrum and low concentrations of zinc and two control groups each using different SLS-containing dentifrices. Dental plaque scores (Turesky modification of Quigley & Hein) and gingivitis scores (Bleeding On Marginal Probing) were assessed at baseline, after 2 and 4 weeks., Results: Eighty-nine participants provided evaluable data. A slight decrease in gingivitis scores was observed for all groups over 4 weeks, which was statistically significant for the non-SLS group. Mean values for dental plaque scores did not show major differences over 4 weeks. For both parameters, no significant differences between groups could be observed at any time point. Patient appreciation was in favour of the SLS groups especially regarding the foaming effect., Conclusion: No significant differences could be observed with respect to the effect on plaque and gingivitis between SLS-containing and SLS-free dentifrice containing enzymes, colostrum and low concentration zinc. Patients enjoyed the duration of taste and the 'foaming effect' of SLS-containing dentifrices better., (© 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Objective: The link between bristle splaying and gingival recession is unclear., Methods: In a 12-month, parallel group, randomized, controlled clinical trial, 110 systemically healthy participants with pre-existing gingival recessions (pre-GR) were assigned to brush their teeth with either a manual (MT) or a powered toothbrush (PT). Every 3 months, toothbrushes and brush heads were replaced. Wear was measured using the Bristle-Splaying-Index (BSI), matched between groups and correlated to the change of pre-GR., Results: Data from 109 subjects (PT, 55; MT, 54) were analyzed. The overall mean BSI was found to be significantly lower (p < 0.001) in the PT group (median 5.5; second and third quartile 1.9-10.0) as compared to the MT group (21.5; 15.0-30.5). After 12 months, pre-GR decreased significantly in the PT group (∆0.2 ± 0.1 mm; p < 0.001) and remained stable in the MT group (∆0.1 ± 0.1 mm; p > 0.05). In the MT group, higher BSI values were associated with a higher risk for increasing or stable recession over 12 months: odds ratio (95 % CI) = 27.9 (1.7; 452.9); p = 0.019., Conclusion: After a mean using time of 3 months, the PT group demonstrated a lower BSI than the MT group, and the greater bristle splaying was associated with a higher risk of increased (or stable) GR in subjects using a MT but not a PT., Clinical Relevance: Compared to a manual toothbrush, powered toothbrushes seem to be utilized with less force and can be considered safe to use in patients with pre-existing gingival recession.

2 334 patients from 29 dental practices took part in a written survey on their experiences with dental treatment in general as well as treatment of periodontal disease (response rate 80.8%). 72.6% of all participating patients fully agreed that they could recommend their dentist to their friends. 63.6% of patients undergoing treatment of periodontitis (N=328) rated this treatment as "excellent". However, for important aspects (prevention, patient information, treatment) potentials for improvement became obvious. 43.7% of patients treated for periodontitis were not completely satisfied with information on how this disease develops; 40.7% saw potentials for better information on preventive care (dental-hygiene, nutrition). An even higher percentage of patients actually not treated for periodontitis was interested in more information on prevention (51.4%). The results of the survey show that dentists should offer information and exercise on how to prevent periodontal desease more actively. There is a lack of research on the present state of affairs and potentials for improvement concerning treatment and prevention of periodontitis including the patients' perspective., (© Georg Thieme Verlag KG Stuttgart · New York.)

Dental caries is the most prevalent disease worldwide, with the majority of caries lesions being concentrated in few, often disadvantaged social groups. We aimed to systematically assess current evidence for the association between socioeconomic position (SEP) and caries. We included studies investigating the association between social position (determined by own or parental educational or occupational background, or income) and caries prevalence, experience, or incidence. Risk of bias was assessed using the Newcastle-Ottawa Scale for observational studies. Reported differences between the lowest and highest SEP were assessed and data not missing at random imputed. Random-effects inverse-generic meta-analyses were performed, and subgroup and meta-regression analyses were used to control for possible confounding. Publication bias was assessed via funnel plot analysis and the Egger test. From 5539 screened records, 155 studies with mostly low or moderate quality evaluating a total of 329,798 individuals were included. Studies used various designs, SEP measures, and outcome parameters. Eighty-three studies found at least one measure of caries to be significantly higher in low-SEP compared with high-SEP individuals, while only 3 studies found the opposite. The odds of having any caries lesions or caries experience (decayed missing filled teeth [DMFT]/dmft > 0) were significantly greater in those with low own or parental educational or occupational background or income (between odds ratio [95% confidence interval] = 1.21 [1.03-1.41] and 1.48 [1.34-1.63]. The association between low educational background and having DMFT/dmft > 0 was significantly increased in highly developed countries (R (2) = 1.32 [0.53-2.13]. Publication bias was present but did not significantly affect our estimates. Due to risk of bias in included studies, the available evidence was graded as low or very low. Low SEP is associated with a higher risk of having caries lesions or experience. This association might be stronger in developed countries. Established diagnostic and treatment concepts might not account for the unequal distribution of caries (registered with PROSPERO [CRD42013005947])., (© International & American Associations for Dental Research 2014.)

Unlabelled: Infectious diseases endanger all dental personnel during treatment, especially when spatter and aerosols are produced. Therefore, there is a strong need for better infection control principles during all treatments. The purpose of this in-vitro pilot study was to measure the environmental spatter contamination through a fluorescence technique. Scaling was performed using different power-driven devices and high-volume evacuation combined with a newly developed cannula (PS), standard suction cannulas (STS) and saliva ejectors (CDS)., Material and Methods: One sonic (AIR) and two ultrasonic devices (TIG, VEC) were utilized to remove biofilm from 168 artificial teeth in a manikin head. Teeth were scaled for 120s supra- or subgingivally. The spatter contamination of an area of 1.5m2 around the manikin head was assessed., Results and Conclusions: The contaminated area (%) was significantly different for the AIR (median [25th; 75th percentiles]: 2.5 [1.16; 6.05]) versus TIG (0.25 [0.18; 0.88]) and VEC (0.08 [0.06; 0.1]) (p<0.001). Irrespective of the instrument, subgingival scaling led to a less contaminated area (0.18 [0.07; 1.05]) than supragingival scaling (0.34 [0.1; 2.24]) (p < 0.001). High-volume evacuation combined with STS (0.17 [0.07; 1.04]) and PS (0.18 [0.07; 1.14]) reduced the contamination similarly (p=0.302) and was more effective compared to CDS (1.01 [0.12-5.78]) (p<0.001; p=0.002). Beside the limitation of an in-vitro investigation, it can be conclude that only high-volume evacuation with an adequately calibrated cannula is capable of significantly reducing the amount of spatter contamination produced during power-driven scaling.

The treatment of deep caries lesions carries significant risks for the integrity of the pulp and often initiates a cascade of re-interventions. Incomplete caries removal may reduce these risks and avoid or delay re-treatment. The present study analyzed the cost-effectiveness of one- and two-step incomplete as well as complete excavations. We used Markov models to simulate treatment of a molar tooth with a deep caries lesion in a 15-year-old patient. Retention of the tooth and its vitality as effectiveness measures as well as accruing costs were analyzed over the patient's lifetime. The model adopted a public-private-payer perspective within German health care. Transition probabilities were calculated based on literature reviews. Monte-Carlo microsimulations were performed with 6-month cycles. One-step incomplete excavation resulted in lower long-term costs and in longer-retained teeth and their vitality (means: 53.5 and 41.0 yrs) compared with two-step incomplete (52.5 and 37.5 yrs) and complete excavations (49.5 and 31.0 yrs), and dominated the other strategies in 70% to 100% of simulations. Regardless of the assumed willingness-to-pay ceiling value, one-step incomplete excavation had the highest probability of being cost-effective. Despite limited evidence levels of input data, we expect one-step incomplete excavation to reduce costs while retaining deeply carious teeth and their vitality for longer.

Increasing numbers of clinical trials have demonstrated the benefits of incomplete caries removal, in particular in the treatment of deep caries. This study systematically reviewed randomized controlled trials investigating one- or two-step incomplete compared with complete caries removal. Studies treating primary and permanent teeth with primary caries lesions requiring a restoration were analyzed. The following primary and secondary outcomes were investigated: risk of pulpal exposure, post-operative pulpal symptoms, overall failure, and caries progression. Electronic databases were screened for studies from 1967 to 2012. Cross-referencing was used to identify further articles. Odds ratios (OR) as effect estimates were calculated in a random-effects model. From 364 screened articles, 10 studies representing 1,257 patients were included. Meta-analysis showed risk reduction for both pulpal exposure (OR [95% CI] 0.31 [0.19-0.49]) and pulpal symptoms (OR 0.58 [0.31-1.10]) for teeth treated with one- or two-step incomplete excavation. Risk of failure seemed to be similar for both complete and incomplete excavation, but data for this outcome were of limited quality and inconclusive (OR 0.97 [0.64-1.46]). Based on reviewed studies, incomplete caries removal seems advantageous compared with complete excavation, especially in proximity to the pulp. However, evidence levels are currently insufficient for definitive conclusions because of high risk of bias within studies.

Background: Proximal contact tightness of class II resin composite restorations is influenced by a myriad of factors. Previous studies investigated the role of matrix band type and thickness, consistency of resin composite, and technique of placement. However, the effect of volumetric shrinkage of resin and intensity of curing light has yet to be determined. Thus, the aim of this study was to identify the influence of these factors on the proximal contact tightness when restoring class II cavity preparations in vitro., Methods: Sixty artificial molars were restored with either a low-shrinkage (Filtek Silorane, 3M ESPE) or a conventional (Z100, 3M ESPE) composite and polymerized with low-intensity (Smartlite IQ2, Dentsply) or high-intensity light curing units (Demi(TM), Kerr). Proximal contact tightness was measured using the Tooth Pressure Meter. Data were statistically analyzed using one-way analysis of variance and Tukey post hoc test., Results: Use of low-shrinkage composite (Filtek Silorane) resulted in significantly tighter proximal contacts compared to the use of conventional composite (Z100) when cured with the same polymerization unit (p<0.001). Moreover, the low-intensity curing unit (IQ2) resulted in significantly tighter contacts than the high-intensity unit when material is constant (p<0.001)., Conclusions: Low-shrinkage resin composite and low curing light intensity is associated with tighter proximal contact values.

1,317 patients from 18 dentists took part in a written survey on patient evaluation of dental care. General satisfaction was high, but patients were critical concerning some aspects of dental care. On average, the aspects rated most often with "excellent" were hygiene in the practice, the possibility to get through to the practice on the telephone and quick service in case of urgent health problems. Most critical evaluations (on average) were given for waiting times, costs of the dental treatment for the patient and the range of magazines and written information in the waiting room. The highest statistical correlation to overall satisfaction (willingness to recommend this doctor to friends) showed the patients' assessments concerning the questions whether the doctor was listening to them and took enough time, as well as the result of the dental treatment from the patients' point of view. Differences of the survey results between practices were high. On average, patients of female dentists were more satisfied than patients of their male colleagues. Patients younger than 50 years and male patients were less satisfied than older patients and female patients. The patient surveys give important clues for quality management in the participating dental practices. The results of a patient survey should be evaluated against the background of the individual situation of the practice.

Objective: The objective of this study was to investigate clinical changes in proximal contact strength inserting Class II composite resin restorations according to one of three randomly assigned protocols., Materials and Methods: Seventy-one Class II restorations (MO/DO) were placed by two calibrated operators. Restorations were randomly assigned to one of three groups: one using a circumferential and two a sectional matrix system with separation rings. Proximal contacts were measured by one independent observer with a Tooth Pressure Meter immediately before treatment, and directly after finishing the restoration., Results: Compared to the situation before treatment groups with a sectional matrix system resulted in a statistical significant stronger mean proximal contact strengths (p<0.05), whereas the use of a circumferential matrix system with hand-instrument resulted in a lower proximal contact strength (p<0.05)., Conclusion: Class II posterior composite resin restorations placed with a combination of sectional matrices and separation rings resulted in a stronger proximal contact than when a circumferential matrix system was used.

Objectives: To compare the cleaning efficacy of a powered toothbrush with 3-dimensional brush head action (Braun Oral-B 3D Plaque Remover D15) and a high-speed "microtation" brush with an additional "microbrush-clip" (Rowenta Dentasonic MH921S)., Material and Methods: 82 healthy subjects took part in the study. After a familiarization period of 8 days, the subjects abstained from all oral hygiene procedures for 48 h. After plaque was scored, the subjects brushed their teeth under supervision with the two brushes according to a split-mouth design. Immediately after brushing, subjects completed a questionnaire and plaque was scored again., Results: The overall plaque scores were found to be significantly reduced from 3.05+/-0.60 to 1.96+/-0.63 by the D15 and from 3.02+/-0.58 to 2.24+/-0.64 by the Dentasonic (p<0.05). The proximal surface plaque scores were reduced from 3.20+/-0.63 to 2.17+/-0.69 by the D15 and from 3.17+/-0.60 to 2.44+/-0.69 by the Dentasonic. The relative plaque reduction was overall 36.6+/-12.2% for the D15 compared to 26.1+/-13.5% for the Dentasonic and at proximal surfaces, 33.1+/-12.3% and 23.2+/-13.0%, respectively. 75% of the subjects stated that they would prefer to keep the D15., Conclusions: Both brushes were able to remove a significant amount of plaque, but the D15 was significantly more effective compared to the Dentasonic. The additional "microbrush-clip" for the proximal embrasures failed to improve plaque removal from these tooth surfaces, compared to the D15 alone.

Purpose: To compare the cleaning efficacy of a battery-powered toothbrush with an oscillating/rotating action (Dr. Best Powerclean) and a standard flat-trimmed manual toothbrush (Elmex super 39) in a single-blind, cross-over clinical study., Materials and Methods: 78 healthy subjects took part in the study. Subjects were asked to abstain from all oral hygiene procedures for 48 hours, after which hard and soft oral tissues were examined. Plaque was then scored using the Turesky modification of the Quigley-Hein Index, and subjects were instructed to brush their teeth for a total time of 1 minute with either one or the other brush, according to a predetermined randomization schedule. Immediately after brushing, plaque was scored again and hard and soft tissues were re-examined. All plaque scoring was carried out by the same investigator who was blind with respect to the brushes used. Subjects were instructed to continue with their usual oral care routine throughout the study period. They were scheduled to return after 12-14 days, having again abstained from all oral hygiene for 48 hours prior to the visit, in order to repeat the evaluation sequence but brushing with the alternative brush. Prior to analysis of the results, data from the two phases of the study were combined., Results: Both toothbrushes were found to be safe as used in the study. Using the non-parametric Wilcoxon test for paired samples, whole mouth plaque scores were found to be reduced significantly from 2.04 +/- 0.60 to 1.57 +/- 0.51 by the Powerclean toothbrush (P < 0.001), and from 1.99 +/- 0.65 to 1.27 +/- 0.52 by the manual toothbrush (P < 0.001). At approximal surfaces, the plaque scores were also significantly reduced from 2.14 +/- 0.0.59 to 1.69 +/- 0.50 for the Powerclean (P < 0.001), and from 2.08 +/- 0.64 to 1.40 +/- 0.57 for the manual toothbrush (P < 0.001). A comparison of the two brushes revealed that the manual toothbrush removed significantly more plaque than the Powerclean, both for the whole mouth and approximal surfaces (P < 0.001). The Powerclean reduced whole mouth plaque by 23.2 +/- 11.5% compared to 37.8 +/- 14.0% for the manual toothbrush and approximal plaque by 20.9 +/- 10.6% and 34.9 +/- 14.0%, respectively. It is concluded that the Dr. Best Powerclean toothbrush is not as effective as a standard flat-trimmed manual toothbrush.

Purpose: To test the hypothesis that simulation of an intrapulpal pressure during the application of dentin bonding systems influences hybrid layer formation in vitro., Materials and Methods: 180 teeth and three different bonding agents were used for shear bond strength measurements and for confocal laser scanning microscopy studies on the dentin-composite interface. The bonding agents (30 teeth each material) were applied without (90 teeth, Group A) and with intrapulpal pressure simulation of 34 cm H20 with water (90 teeth, Group B). 45 specimens from each group were sheared in a testing machine, and 45 teeth from each group were used for CLSM studies after labeling the primer components of the bonding agents with a fluorescent dye., Results: After simulation of pulpal pressure the bond strengths decreased significantly in all groups (Syntac [without/with]: 16.0 +/- 4.5/8.0 +/- 3.7, P= 0.001; Gluma: 13.3 +/- 4.6/8.4 +/- 4.4, P= 0.008; Prime & Bond NT: 14.8 +/- 5.8/8.7 +/- 5.7, P= 0.007; n = 15 each; U-tests). There were no significant differences between the hybrid layer thickness without/with simulation of pulpal pressure (Syntac: 3.6 +/- 0.6/4.1 + 1.2, P= 0.35; Gluma: 3.5 +/- 0.6/3.7 + 0.9, P= 0.49; Prime & Bond NT: 3.5 +/- 0.9/3.8 + 0.8, P= 0.44; n = 15 each; U-tests). In the case of simulation of an intrapulpal pressure, CLSM examination revealed a distinctly shallower penetration of the adhesives into dentin compared to the samples treated without intrapulpal pressure.

Purpose: To compare the clinical efficacy with respect to plaque removal of a battery-operated power toothbrush (Dr. Johns Spin Brush Classic) with two manual toothbrushes, a standard ADA flat trim reference brush and the Oral-B CrossAction toothbrush., Materials and Methods: Efficacy was evaluated in two independent studies using a randomized, single-use, cross-over design. Healthy adult subjects from a general population brushed their teeth for a timed 1 min and plaque was scored before and after brushing was completed. In Study 1 (Spin Brush vs. ADA toothbrush), plaque was scored using the modified Quigley and Hein Plaque Index, while in Study 2 (Spin Brush vs. CrossAction) plaque was scored using the Modified Navy Plaque Index. In addition, a hard and soft tissue examination was carried out before and after brushing to allow evaluation of safety., Results: In Study 1, both the ADA toothbrush and the Spin Brush significantly reduced levels of whole mouth and approximal plaque (P < 0.0005); however, the Spin Brush was not significantly more effective than the manual brush. Relative plaque reduction for the whole mouth was 35.6 +/- 16.0% for the Spin Brush compared to 38.9 +/- 14.9% for the manual toothbrush (P < 0.047), and, for the approximal surfaces, 32.7 +/- 14.6% and 36.3 +/- 13.7%, respectively (P = 0.024). In Study 2, both toothbrushes significantly reduced plaque levels (P < 0.0001), but, as for Study 1, the CrossAction manual toothbrush was more effective than the Spin Brush. For whole mouth, marginal and approximal sites, respectively, the Spin Brush reduced plaque by 54.3%, 43.5% and 62.0%, compared with 58.6%, 47.5% and 67.1% for the CrossAction toothbrush. The difference in favor of the CrossAction brush was statistically significant (P < 0.0005) for all areas.

The term "nanoleakage" has been introduced to explain a penetration pathway within hybrid layers of the dentin-composite junction in the absence of gap formation. This phenomenon is argued in the literature to be a risk factor for the quality of the dentin bonding. NaOCl is a well-known agent used to remove collagen layers that are exposed after acid etching. The purpose of this study was to determine the influence of an NaOCl treatment of dentin to the formation of nanoleakage. Class V cavities were prepared in 40 human molars with the cervical margins located in dentin. After etching with phosphoric acid, 20 samples were treated with 10% NaOCl for 60 s, and 20 samples were used as control. Composite restorations were placed using two different bonding systems. The specimen were exposed in silver nitrate solution and then in developer. After embedding, the teeth were sectioned, dried, coated with gold, and analyzed by SEM. For all the specimen in the control group, backscatter images indicated a silver penetration within the hybrid layer. There was no penetration of silver detectable in the teeth that were treated with NaOCl. We conclude that the removal of the collagen layer by using NaOCl avoids the formation of nanoleakages with the materials tested., (Copyright 2001 John Wiley & Sons, Inc. J Biomed Mater Res 56: 578--583, 2001)

Background: (I) Introducing an intraoral camera system with a special positioner to allow computer-based analysis of reproducible images on lingual tooth surfaces and (II) comparing plaque removal by three manual toothbrushes with different brushhead designs (convex, multilevel and flat trimmed) on lingual mandibular tooth surfaces., Method: In a clinical single-blind, crossover, 24-h plaque-regrowth study on 25 subjects, a computer-based index (PPI) was used to evaluate pre- and postbrushing plaque on lingual surfaces of mandibular premolars and molars. Subjects brushed their teeth under standardized conditions at three visits, each time with a different, randomly assigned toothbrush., Results: The intraoral camera system allowed a reproducible and relatively convenient access to the lingual surfaces of the mandibular teeth and provided an increase in objectivity. Overall, each brush achieved statistically significant plaque removal, however, none reached clinical relevance. The multilevel brush was superior at specific sites, but failed to show statistically significant superiority in terms of overall plaque reduction. Without regard of the toothbrush used, the right handed subjects were less efficient in removing plaque from the right side compared to the left., Conclusions: The method is able to detect even small differences in plaque reduction. None of the different brushhead designs was able to compensate an insufficient brushing techniques.

Purpose: To clinically measure the influence of rubber-dam on the proximal contact strength after its reconstruction with tooth-colored restorations., Materials and Methods: The frictional forces during the removal of a metal strip from the proximal contact area were taken as measure for the proximal contact strengths of 46 restorations (35 ceramic inlays, 11 direct composite restorations). The teeth were separated with a rubber-dam and wedged thoroughly during the complete reconstruction procedure according to the multiple wedging technique. The proximal contact strengths were measured immediately before and immediately after removing the rubber-dam., Results: The contact strengths were statistically significantly lower immediately after the removal of the rubber-dam (1.07+/-0.82N) compared to the situation with the rubber-dam (1.99+/-1.21N). The amount of the reduction after removing the rubber-dam was statistically significantly higher between the second premolar and the first molar (1.45+/-1.06N) compared to the contacts between the canines and the first premolar (0.32+/-0.44N) and the first and second premolar (0.59+/-0.77N). No influence of the restorative material, the use and localization of retainers, localization of the restoration, or number of teeth under the rubber-dam was detectable., Conclusion: Rubber-dam is recommended for adhesive restorations as it is helpful for achieving good adhesion between the tooth and restorative materials. Nevertheless, the application of rubber-dam seems to be a factor which complicates the reconstruction of adequate proximal contacts.

Background: One of the major concerns with the use of dental floss is the passage of the proximal contact, which might be influenced by the material characteristics of the floss. The aim of this study was to compare the gliding capacities of different flosses with major differences in structure and experimental behavior in vivo., Methods: In a clinical, single-blind, crossover study of 27 subjects, the forces necessary for passing all 14 proximal contacts between the first premolars were measured using 2 polytetrafluoroethylene (PTFE)-based flosses, 2 nylon-based flosses, and 1 nylon-based tape. The flosses were fixed in a special holder with strain gauges, which allowed registration of the maximum forces at insertion into and removal from the interdental area., Results: In most contacts, the PTFE flosses needed less force compared to the nylon flosses. The range between the flosses was higher in the mandible compared to the maxilla and increased from the mesially located contacts to the more distally located contacts. The nylon tape required higher forces at insertion for all maxillary contacts. All other flosses proved to be equivalent at these contacts., Conclusions: PTFE flosses are superior to nylon flosses in terms of passing stronger proximal contacts in both directions. Due to gliding differences between different types of floss, the selection of a floss has the potential of compensating intra- and interindividual variation in contact strengths.

The aim of this study was to systematically measure proximal contact strength in complete natural dentitions of 30 adults (25.3 +/- 3.0 years of age), and to analyze its relationship to tooth type, tooth location, chewing effort and time of day variation. The contact strengths were measured dynamically during removal of a calibrated 0.05-mm-thick metal strip between the proximal contacts of adjacent teeth. Proximal contact strengths were lower in the maxilla (2.51 +/- 1.36 N) compared to the mandible (4.26 +/- 1.88 N). Within the jaws, the lowest proximal contact strength was measured between canine and first premolar (2.91 +/- 1.79 N) and the highest between second premolar and first molar (3.73 +/- 1.95 N). Chewing increased the proximal contact strength within the maxilla (before: 2.51 +/- 1.36 N, after: 3.02 +/- 1.45 N) but it remained unchanged in the mandible (before: 4.26 +/- 1.88 N, after: 4.22 +/- 1.85 N). The proximal contact strength increased significantly from morning (3.39 +/- 1.86 N) to noon (3.61 +/- 1.77 N), and then decreased in the afternoon (3.43 +/- 1.60 N). It was concluded that proximal contact strength can be significantly influenced by location, tooth type, chewing and time of day variation. Based on the differences in distribution due to the effect of chewing and time of day, it is speculated that proximal contact strength is a physiological entity of multifactorial origin.

"Nanoleakage" takes place within the hybrid layer zone of the dentin-composite interface in spaces not occupied by polymerized resin. The purpose of this study was to quantify the amount of nanoleakage in specimens treated with one of six different bonding agents. For one agent, different etching times were used, and for two agents results after thermocycling were obtained. Standardized class V cavities were prepared in 165 extracted human molars with cervical margins located in dentin. After placement of the composite using bonding agents, the teeth were stored in a 1% rhodamin-B-isothiocyanate solution for 24 h at 20 degrees C, embedded in methacrylate, and sectioned parallel to the long axis of the tooth. A confocal laser scanning microscope was used to visualize a layer 10 microm below the prepared surface of the section. The lengths of the penetrated pathways were measured, representing the amount of nanoleakage. In all materials tested, penetration pathways appeared within the hybrid layer in absence of gap formation. Penetration lengths of the tested materials were in a range from 69 +/- 24 microm to 469 +/- 333 microm. Thermocycling had no statistically significant influence, and etching for 15 s resulted in statistically significantly shorter penetration compared to longer etching.

Aim: The comparison of the effects of guided-tissue regeneration (GTR) using 2 different biodegradable barriers (polylactide acetyltributyl citrate; polydioxanon) in 3- and 2-wall intrabony defects., Method: The polydioxanon barrier is an experimental membrane for GTR therapy that consists of an continuous occlusive barrier that has a layer of slings on the side that is meant to face the mucoperiosteal flap. 15 patients provided 15 pairs of similar contralateral periodontal defects: 12 predominantly 2-wall and 18 predominantly 3-wall intrabony defects. Each defect was randomly assigned to treatment with either polylactide acetyltributyl citrate (control [c]) or polydioxanon (test [t]) devices. At baseline and 6 months after surgery, clinical measurements (P1I, GI, PPD, PAL-V) were performed., Results: Barrier exposure was commonly observed in both groups (control/test): 5/4 after 7 days, 9/11 after 14 days and 11/12 after 28 days postsurgically. 4 weeks after surgery, 77% of all barriers were exposed to some extent. However, both treatments revealed a significant GI reduction (p<0.05), PPD reduction [-4.63+/-1.85 mm (t), -4.17+/-1.89 mm (c); p<0.001] and PAL-V gain [3.97+/-1.17 mm (t), 3.40 mm+/-1.40 (c); p<0.001] 6 months after surgery. Regarding GI and PPD reduction as well as PAL-V gain, there were neither statistically significant nor clinically relevant differences between test and control: similar clinical results were found 6 months after surgical treatment using both biodegradable barriers., Conclusions: Based on the results of the present study, the use of both biodegradable barriers in GTR therapy may be recommended.