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Objectives: While air polishing with abrasive powders has been proved efficient for sub- and supragingival application, only few studies concerning the quality of supragingival biofilm removal using the low-abrasive erythritol powder (EP) exist. The aim of the present randomized controlled trial was to clinically compare the efficacy of supragingival air polishing using EP in comparison with the rubber cup method, and to juxtapose the corresponding biofilm regrowth rates. Method and materials: Thirty-two young adults, suspending oral hygiene for 48 hours, were enrolled in the present double-blind short-term investigation. Using a split-mouth design, tooth polishing was conducted by means of either air polishing or rubber cups with prophylaxis paste (control). While 16 participants received air polishing in the second and fourth quadrants (and rubber cup prophylaxis in the first and third ones), the reverse sequence was applied with the remaining 16 subjects. Biofilms were assessed using the modified Quigley-Hein index (QHI), and QHI sum scores achieved both prior to and immediately after the polishing procedure, as well as 24 hours later, were assessed using a two-way analysis of variance (ANOVA), followed by Tukey’s HSD to test multiple pairwise comparisons. Results: Both methods revealed a significant reduction of QHI scores (P < .001). Compared to the rubber cup method, air polishing resulted in significantly lower scores, both after tooth cleaning and after 24 hours (P < .001). Conclusions: Supragingival biofilm removal by means of air polishing combined with low-abrasive erythritol seems to be more efficacious than the traditional polishing method, and should improve oral health care. Keywords: air polishing, biofilm, erythritol, low-abrasive powder, oral hygiene, plaque, professional tooth cleaning, rubber cup polishing

Purpose: To determine how the currently available techniques of scaling and root planing, used either alone or with additional polishing techniques, affect the substance thickness and surface roughness of enamel and cementum. Materials and Methods: After extraction, impacted third molars were prepared and subjected to air polishing with a nonabrasive powder, ultrasonic scaling, or hand instrumentation. All three techniques were performed alone and in combinations for a total of 9 treatment groups. The control group consisted of untreated surfaces. Optical microcoordination measurements were conducted to separately assess substance loss, mean roughness depth (Rz), and roughness average (Ra) on enamel and cementum. The Rz results were analysed using a t-test for paired samples. Results: Air polishing alone and with additional rubber-cup polishing using a paste were the only two approaches which caused no enamel loss. Both groups also entailed less cementum loss (≤ 20 μm) than any of the other seven groups, and both yielded the most favorable Rz results on enamel. Air polishing alone was the only group to reveal no significant change in Rz from untreated cementum (p = 0.999). The other 8 approaches statistically significantly reduced the surface roughness of cementum (p ≤ 0.017). Conclusion: Air polishing with a nonabrasive powder yielded the best hard-tissue preservation. Combining any of the scaling techniques with additional polishing was not beneficial; on the contrary, they caused even more abrasion of hard tissue on both enamel and cementum. Keywords: cementum, enamel, hand instruments, substance loss, surface roughness, ultrasonic air polishing

Bei Zahnerosionen ist eine steigende Prävalenz zu beobachten. Aufgrund der irreversiblen Zerstörung und der voranschreitenden Progression kann die Lebensqualität betroffener Personen beeinträchtigt werden. Frühprophylaktische Maßnahmen sind daher von großer Bedeutung. In Beratungsgesprächen mit dem zahnärztlichen Fachpersonal kommt immer wieder die Frage nach der Erosivität verschiedener Getränke und Speisen auf, denn sie spielen eine wichtige, vom Patienten kontrollierbare Rolle bei der Entstehung der Erosionen. Es bestehen beträchtliche Unterschiede hinsichtlich des erosiven Potenzials. So gibt es saure Produkte, die keine Erosionen verursachen, und solche mit höherem pH-Wert, die ein größeres erosives Potenzial aufweisen. Der Beitrag beleuchtet den Einfluss der Ernährung auf die Entstehung und Progression von Erosionen und diskutiert die Frage, was man bei Erosionen besser nicht essen sollte. Keywords: Zahnerosionen, erosiver Zahnverschleiß, pH-Wert, Calciumgehalt, erosives Potenzial, Demineralisation, Zahnhartsubstanzschäden

Purpose: During biofilm formation, bacterial species do not attach directly onto the enamel surface, but rather onto the salivary pellicle. Salivary pellicle modification with casein and mucin can hinder erosive demineralisation of the enamel, but it should also not promote bacterial adhesion. The aim of our study was to assess whether salivary pellicle modification with casein, or mucin, or a mixture of both proteins (casein and mucin) influence bacterial adhesion, biofilm diversity, metabolism and composition, or enamel demineralisation, after incubation in: (a) a single bacterial model; (b) a five-species biofilm model; or (c) biofilm reformation using the five-species biofilm model after removal of initial biofilm with toothbrushing. Materials and Methods: Enamel specimens were prepared from human molars. Whole-mouth stimulated human saliva was used for pellicle formation. Four pellicle modification groups were established: control (non-modified pellicle); casein – modified with 0.5% casein; mucin – modified with 0.5% mucin; casein and mucin – modified with 0.5% casein and 0.5% mucin. Bacterial adhesion, biofilm diversity, metabolic activity, biofilm mass, and demineralisation (surface hardness) of enamel were assessed after incubation in bacterial broths after 6 h or 24 h. Results: After 24 h incubation in the five-species biofilm model, the mucin group presented significantly lower biofilm mass than the control (p = 0.028) and the casein and mucin (p = 0.030) groups. No other differences between the groups were observed in any of the other experimental procedures. Conclusion: Pellicle modification with casein and mucin does not promote in vitro bacterial biofilm formation. Keywords: biofilms, casein, demineralisation, enamel, mucin, salivary pellicle, salivary pellicle modification

Purpose: The effects of arginine as a toothpaste additive were assessed on oral streptococci with and without a known arginine deiminase system (ADS) and cariogenic biofilms. Materials and Methods: Suspensions of Streptococcus mutans, S. sobrinus and the ADS-positive (ADS+) S. sanguinis and S. gordonii were cultured with or without 1.5% L-arginine for 24 h. Thereafter, biofilms consisting of the four species were formed on polystyrene surfaces with or without 1.5% L-arginine for up to 10 d. Finally, biofilms that formed on enamel surfaces were exposed to a daily mechanical cleaning with an arginine and sodium monofluorophosphate (SMF+Arg)-containing toothpaste, a sodium monofluorophosphate fluoride (SMF)-containing toothpaste or a negative control for up to 10 weeks. At different incubation times, the pH in the culture media, the citrulline production and the percent of ADS+ bacteria within the biofilms were determined. Microsurface hardness loss was quantified in the experiments using enamel specimens. Results: In the presence of 1.5% arginine, S. sanguinis and S. gordonii showed a high level of production of citrulline after 6 h of incubation, together with an increase in the pH when compared to S. mutans and S. sobrinus. With arginine supplementation, the percentage of ADS+ species was higher at 1, 2 and 4 days and citrulline production was higher at all days of biofilm formation on polystyrene surfaces. After 4 and 10 weeks of treating biofilms on enamel surfaces, the SMF+Arg group had a higher proportion of ADS+ strains than the SMF group; at 4 weeks, the pH was higher in the SMF+Arg group. Loss of enamel hardness was the lowest in the SMF+Arg group and was significantly less in the SMF+Arg group than in the control group after 2, 4 and 10 weeks of treatment. Conclusion: Toothbrushing using an arginine-containing toothpaste may protect against dental caries. Keywords: arginine, citrulline, multispecies biofilm, microsurface hardness, oral streptococci

Purpose: Using the ICDAS (International Caries Detection and Assessment System), to assess caries experience in the primary dentition of preschool children living in a socioeconomically poor area with a nonfluoridated water supply, and to compare the stages of caries manifestation between children from private and public schools. Materials and Methods: This census included all children aged 3 to 5 years from public and private schools from Teixeira, Brazil. Clinical examinations were carried out by two calibrated examiners using ICDAS, the results of which were converted into components of dmf-s and dmf-t. Results: The majority of children had caries; the prevalence of enamel and dentin lesions was 81.7%. The prevalence of dentin lesions alone was 62.1%. The mean values of the d2mf2-s/d2mf2-t indices (enamel and dentin lesions) and d3mf3-s/d3mf3-t indices (dentin lesions) were 13.5 ± 14.9/6.8 ± 5.8 and 7.4 ± 10.9/3.0 ± 3.6, respectively. There was no significant difference between the dmf-s/dmf-t indices of children from private vs public schools (p > 0.05). Conclusion: Caries was highly prevalent in the primary dentition of this Brazilian population, and the presence of noncavitated lesions was the most prevalent condition. Children from private and public schools showed similar caries experience. Keywords: dental caries, ICDAS, oral health, preschool children, primary teeth

Der Beitrag fasst die europäische Konsensus-Leitlinie zur zahnärztlichen Therapie bei fortgeschrittenem Zahnhartsubstanzverlust zusammen. Er fokussiert auf die Definition von physiologischem versus pathologischem Zahnhartsubstanzverlust und empfiehlt, die Diagnostik, Prävention, Aufklärung und Überwachung auf die Ätiologie, die Art und das Ausmaß des pathologischen Zahnhartsubstanzverlustes sowie Mittel zu seiner Kontrolle auszurichten. Therapieentscheidungen werden von vielen Faktoren beeinflusst und sind sowohl vom Schweregrad und von den klinischen Auswirkungen des Zahnhartsubstanzverlustes als auch von den Wünschen des Patienten abhängig. Idealerweise werden restaurative Maßnahmen so lange wie möglich hinausgezögert. Wenn eine solche Intervention indiziert ist und der betroffene Patient zustimmt, wird ein konservierender minimalinvasiver Ansatz mit ergänzenden Präventionsmaßnahmen empfohlen. Beispielhaft werden adhäsive minimalinvasive Therapiekonzepte vorgestellt. Keywords: Zahnhartsubstanzverlust, Entscheidungsfindung, restaurative Behandlung, direkte Restauration, indirekte Restauration

This paper presents European expert consensus guidelines on the management of severe tooth wear. It focuses on the definition of physiological vs pathological tooth wear and recommends diagnosis, prevention, counseling, and monitoring aimed at elucidating the etiology, nature, rate and means of controlling pathological tooth wear. Management decisions are multifactorial, depending principally on the severity and effects of the wear and the wishes of the patient. Restorative intervention is typically best delayed as long as possible. When such intervention is indicated and agreed upon with the patient, a conservative, minimally invasive approach is recommended, complemented by supportive preventive measures. Examples of adhesive, minimum-intervention management protocols are presented. Keywords: tooth wear, decision making, restorative treatment, direct, indirect

Purpose: To investigate the effect of relative humidity and saliva contamination on short- and long-term bond strength of two self-etch adhesives to normal and artificially eroded dentin. Materials and Methods: A total of 480 dentin specimens were produced from extracted human molars. Half of the specimens (n = 240) were left untreated (normal dentin) whereas the other half (n = 240) were artificially eroded. The specimens were treated with Clearfil SE Bond (CSE) or Scotchbond Universal (SBU), and composite (Filtek Z250) was applied to the treated dentin surface under four experimental conditions: at a relative humidity of 45% or 85% without/with human saliva contamination. Shear bond strength (SBS) was measured after storage for 24 h (100% humidity; 37°C) or 1 year (tap water; 37°C). SBS results were statistically analyzed with a nonparametric ANOVA followed by Wilcoxon-Mann-Whitney tests (significance level: ? = 0.05). Results: SBS was significantly influenced by the dentin substrate (normal or artificially eroded dentin) and adhesive (p < 0.001) but not by relative humidity, saliva contamination, or storage. SBS significantly differed (all p < 0.001) following the ranking (MPa; medians [pooled]): SBU on normal dentin (21.1) > CSE on normal dentin (19.2) > SBU on artificially eroded dentin (17.1) > CSE on artificially eroded dentin (10.9). Conclusion: On normal dentin, the two self-etch adhesives showed stable bond strength over time even under adverse conditions such as high relative humidity and saliva contamination. However, erosively altered dentin had a detrimental effect on the bond strength of both the adhesives investigated. Keywords: adhesion, adhesive treatment, 10-MDP, pH cycling, air moisture, salivary contamination

Neben der Vermeidung und Versorgung kariöser Defekte nimmt die Prävention vor sowie die Therapie von nicht-kariösen Defekten wie Erosionen und erosivem Zahnhartsubstanzverlust einen immer größer werdenden Stellenwert ein. Insbesondere in industrialisierten Ländern werden durch den Rückgang von Karies, eine bessere Mundhygiene und einen gesünderen Lebensstil - verbunden aber mit mehr Stress und der besseren Aufklärung und Fortbildung von Personen im Mundgesundheitsbereich - Erosionen als Folge von nicht-bakteriellen Säureangriffen auf die Zahnhartsubstanz vermehrt wahrgenommen. Dieser Artikel soll eine Übersicht über die verschiedenen Ursachen, die Schwierigkeiten in der Diagnostik sowie die Therapie von und auch die Prophylaxe vor erosivem Zahnhartsubstanzverlust geben.