Limosilactobacillus reuteri supernatant attenuates inflammatory responses of human gingival fibroblasts to LPS but not to elevated glucose levels.

AIM: We investigated the in vitro effect of Limosilactobacillus reuteri DSM 17938 supernatant on the inflammatory response of human gingival fibroblasts (HGF) challenged by lipopolysaccharide (LPS) or elevated glucose levels. METHODS: HGF were exposed to LPS (1 µg/mL), glucose (5, 12 mM or 25 mM), and dilutions of supernatant prepared from L. reuteri DSM 17938 (0.5 × 107, 1.0 × 107, 2.5 × 107, and 5.0 × 107 CFU/mL). After 24 h cell viability and levels of cytokines (IL-1ß, IL-6 and IL-8) and TLR-2 were determined. RESULTS: None of the tested L. reuteri (DSM 17938) supernatant concentrations reduced the viability of HGF. Supernatant concentrations (2.5 × 107 and 5 × 107 CFU/mL) significantly (p < .05) decreased the production of IL-1ß, IL-6, IL-8, and TLR-2 in the presence of LPS. In contrast, inflammatory markers were not reduced by L. reuteri supernatant in the presence of glucose. Glucose concentrations of 12 mM and 24 mM still lead to an elevated production of the investigated biochemical mediators. CONCLUSION: While L. reuteri (DSM 17938) supernatant attenuates the inflammatory response of HGF to LPS in a dose-dependent manner, elevated glucose levels suppress this action. These in vitro results support the overall anti-inflammatory efficacy of L. reuteri supplementation in plaque-associated periodontal inflammations.

Administration of systemic antibiotics during non-surgical periodontal therapy-a consensus report.

AIM: The aim of this meta-review was to evaluate whether there is a meaningful clinical benefit regarding the use of systemic adjunctive antibiotics in the treatment of patients with periodontitis. Additionally, a consensus regarding possible recommendations for future administration of antibiotics should be reached. METHODS: A structured literature search was performed by two independent investigators focusing on systematic reviews (SR) covering adjunctive systemic antibiosis during non-surgical periodontal therapy. Additionally, recent randomized clinical trials (RCT, July 2015 to July 2017) were searched systematically to update the latest SR. Results were summarized and discussed in a plenary to reach a consensus. RESULTS: Mostly, systematic reviews and RCTs showed a significant positive effect of adjunctive systematic antibiosis compared to controls. These positive effects gain clinical relevance in patients with severe periodontal disease aged 55 years and younger. CONCLUSION: Systemic antibiotics as an adjunct to non-surgical periodontal therapy should be sensibly administered and restrictively used. Only certain groups of periodontitis patients show a significant and clinically relevant benefit after intake of systemic antibiosis during periodontal therapy. CLINICAL RELEVANCE: Avoiding antibiotic resistance and possible side effects on the human microbiome should be a focus of dentists and physicians. Thus, a sensible administration of antibiotics is mandatory. This manuscript suggests guidelines for a reasonable use.

Periodontal education and assessment in the undergraduate dental curriculum-A questionnaire-based survey in European countries.

OBJECTIVES: This survey aimed to evaluate whether periodontal education and assessment in undergraduate dental curricula amongst the member countries of the European Federation of Periodontology (EFP) follow the competency-based curricular guidelines and recommendations developed by the Association for Dental Education in Europe. MATERIALS AND METHODS: A multiple-choice questionnaire was emailed to 244 dental institutes amongst the 24 EFP member countries between November 2014 and July 2015. RESULTS: Data were received from 16 (66.7%) EFP member countries. Out of 117 responding dental institutes, 76 (64.95%) were included as valid responders. In most of the institutes (86.3%), a minimum set of competencies in periodontology was taken into account when constructing their dental education programmes. Out of 76 responders, 98.1% included lecture-based, 74.1% case-based and 57.1% problem-based teaching in their periodontal curricula, whilst a minority (15.9%) also used other methods. A similar pattern was also seen in the time allocation for these four educational methods, that is, the highest proportion (51.8%) was dedicated to lecture-based teaching and only a small proportion (5.7%) to other methods. Periodontal competencies and skills were most frequently assessed by clinical grading on clinic, multiple-choice examination (written examination) and oral examination, whereas competency tests and self-assessment were rarely used. Only in 11 (14.5%) cases, access flap procedures were performed by students. CONCLUSION: Great diversity in teaching methodology amongst the surveyed schools was demonstrated, and thus, to harmonise undergraduate periodontal education and assessment across Europe, a minimum set of recommendations could be developed and disseminated by the EFP.

Effect of Periodontal Treatment on HbA1c among Patients with Prediabetes.

Evidence is limited regarding whether periodontal treatment improves hemoglobin A1c (HbA1c) among people with prediabetes and periodontal disease, and it is unknown whether improvement of metabolic status persists >3 mo. In an exploratory post hoc analysis of the multicenter randomized controlled trial "Antibiotika und Parodontitis" (Antibiotics and Periodontitis)-a prospective, stratified, double-blind study-we assessed whether nonsurgical periodontal treatment with or without an adjunctive systemic antibiotic treatment affects HbA1c and high-sensitivity C-reactive protein (hsCRP) levels among periodontitis patients with normal HbA1c (≤5.7%, n = 218), prediabetes (5.7% < HbA1c < 6.5%, n = 101), or unknown diabetes (HbA1c ≥ 6.5%, n = 8) over a period of 27.5 mo. Nonsurgical periodontal treatment reduced mean pocket probing depth by >1 mm in both groups. In the normal HbA1c group, HbA1c values remained unchanged at 5.0% (95% CI, 4.9% to 6.1%) during the observation period. Among periodontitis patients with prediabetes, HbA1c decreased from 5.9% (95% CI, 5.9% to 6.0%) to 5.4% (95% CI, 5.3% to 5.5%) at 15.5 mo and increased to 5.6% (95% CI, 5.4% to 5.7%) after 27.5 mo. At 27.5 mo, 46% of periodontitis patients with prediabetes had normal HbA1c levels, whereas 47.9% remained unchanged and 6.3% progressed to diabetes. Median hsCRP values were reduced in the normal HbA1c and prediabetes groups from 1.2 and 1.4 mg/L to 0.7 and 0.7 mg/L, respectively. Nonsurgical periodontal treatment may improve blood glucose values among periodontitis patients with prediabetes (ClinicalTrials.gov NCT00707369).

Isolation of noncollagenous proteins from gingival connective tissue.

Noncollagenous proteins form an integral part of gingiva and other connective tissues. We have performed studies aimed at purification and partial characterization of the gingival noncollagenous proteins. Healthy gingival tissues from mongrel dogs were extracted in neutral buffers, acetic acid, and 6 mol/L urea. Immunoblots using anti-keratin antibodies and CNBr peptide patterns revealed that the majority of the proteins present in these extracts were keratins. To exclude keratins, gingival connective tissue was separated from the epithelium and then extracted. Acid extracts of the connective tissue contained very little protein, whereas urea extracts contained collagen and other noncollagenous proteins. The noncollagenous proteins present in the urea extract were partially purified by DEAE-cellulose chromatography and separated by affinity chromatography through a Sepharose 4B-type I collagen column. At least eight proteins, which ranged in molecular size from 15 to 75 kilodaltons, were obtained by this procedure. We conclude that keratins are major components of whole gingiva extracts and that epithelium must first be removed in order for connective tissue proteins to be obtained. The gingival connective tissue appears to contain several collagen-binding proteins, and these proteins may play an important role in the structure and function of the gingival matrix.

Influence of repeated chlorhexidine varnish applications on mutans streptococci counts and caries increment in patients treated with fixed orthodontic appliances.

The occurrence of new carious lesions is among the most detrimental side effects in subjects undergoing orthodontic therapy with fixed appliances. The present study evaluated the efficacy of repeated applications of a 40% chlorhexidine varnish in this patient group with regard to long-term suppression of elevated mutans streptococci levels and the frequency and location of new carious lesions. Thirty-three prospective orthodontic patients age 11 to 18 harboring more than 10(5) mutans streptococci per ml saliva at the initial examination participated in the study. At baseline the previous carious involvement in each subject was recorded using the DMFS index, and extensive information on caries prevention was given. Using a random assignment 18 subjects were included in the test group while the remaining 15 subjects were assigned to the placebo group. From the time of banding until removal of the fixed appliances (median: 21 months) salivary mutans streptococci counts were recorded once every 8 weeks in both groups. At the same appointments all teeth and introaral appliances in the test group were coated with a 40% chlorhexidine varnish. Subjects in the placebo group were treated in the same way, using a placebo varnish with the same varnish base. After debanding, the DMFS score of each participant was recorded again. Analysis of the data revealed that mutans streptococci counts in the test group were only temporarily suppressed and were restored almost to baseline levels by the end of the study. In both groups a clinically relevant increase in the average DMFS score was recorded. Inter-group differencies were not significant.

Recolonization of mutans steptococci on teeth with orthodontic appliances after antimicrobial therapy.

The aim of the present study was to compare the recolonization pattern of mutans streptococci on densely colonized teeth with and without fixed orthodontic appliances after treatment with a 40 per cent chlorhexidine (CHX) varnish (EC 40, Explore). Healthy subjects free of carious lesions requiring fixed orthodontic appliance treatment but with high bacterial mutans streptococci saliva counts were recruited (n = 10). For baseline registration, plaque from buccal sites was sampled and cultivated on Dentocult strips. Following professional tooth cleaning, CHX varnish was applied to all teeth for 8 minutes. Subsequently, orthodontic brackets and bands were inserted in either the upper or lower arch. Eight weeks after varnish application the degree of recolonization with mutans streptococci was reassessed on the buccal sites. Statistical analysis showed that recolonization with mutans streptococci was significantly higher (P < 0.05) on teeth with orthodontic appliances. The results indicate that the use of fixed orthodontic appliances creates artificial environments suitable for the proliferation of mutans streptococci after CHX varnish suppression.

Clinical and microbiological caries-risk parameters at different stages of dental development.

Caries incidence and activity in general are not linear functions, but show several intensity peaks at different stages of life. The purpose of this study was to evaluate, whether the transition from the primary to the permanent dentition is accompanied by any significant changes in several clinical and microbiological parameters commonly used as predictors of caries activity. Sixty children and adolescents, aged 3 to 16, participated in the study and according to age were assigned to 4 different dentition groups (primary, early mixed, late mixed, permanent). The results indicate, that there is a significant decrease in salivary Streptococcus mutans and Lactobacillus spp. counts in the late mixed dentition group compared to the primary and the early mixed dentition group. Furthermore, in the permanent dentition group the stimulated salivary flow rate was significantly higher than in all other groups. Differences regarding plaque score and salivary buffering capacity were not significant for all groups examined. It is concluded, that the transition from the primary to the permanent dentition in general is accompanied by significant, yet temporary decline in the numbers of caries-associated microorganisms, reflecting marked differences in caries incidence and activity, previously reported by other authors.

[Subgingival irrigation in periodontal therapy]. / Subgingivale Taschenspülungen in der systematischen Parodontaltherapie.

Subgingival plaque control is a decisive factor in periodontal therapy. Up to the present, removal of plaque and calculus by repeated scaling procedures has been regarded as the only viable method to achieve this goal. Recent investigations, however, suggest that the topical application of antibacterial substances or subgingival irrigation procedures are capable of yielding comparable improvements of periodontal health. This review paper is dedicated to subgingival irrigation. Besides an overview of techniques and results, we discuss our own experiences, including two case presentations. The results so far are encouraging. Nevertheless, due to the general lack of scientific data with extended time intervals, this method is not suitable yet as an alternative to conventional procedures in periodontal routine care. Until further long-term evidence has been gathered, subgingival irrigation should be regarded only as a valuable adjunct to scaling and root planing.

Influence of toothbrushing, eating and smoking on Dentocult SM Strip mutans test scores.

The Dentocult SM Strip mutans test (D-SM, Vivadent) is a popular method for estimating salivary mutans streptococci and is clinically used for the detection of potential caries risk patients. The influence of toothbrushing, eating and smoking on the reliability of D-SM test scores was assessed in 30 subjects aged 21-39 years. All experiments were performed 24 h after professional tooth cleaning in the morning of 3 consecutive days. On day 1 immediately before and 30 min after toothbrushing, D-SM tests were taken and total salivary colony-forming units per ml were determined. Following the same protocol, the influence of a standardized breakfast and of smoking was evaluated on day 2 and on day 3 respectively. Although all parameters significantly decreased the salivary colony-forming units per ml, only the standardized breakfast induced significant changes in the D-SM test results. Eating therefore should be avoided prior to the performance of the D-SM test.

[The effect of an extended initial therapy on molars and single-rooted teeth]. / Der Effekt einer erweiterten Initialbehandlung auf Molaren und einwurzelige Zähne.

The purpose of this study was to evaluate the benefits of an initial periodontal therapy consisting of a single subgingival root debridement procedure followed by repeated monthly subgingival irrigations over a period of 6 months in 23 patients with multiple advanced periodontal lesions. The clinical and microbiological data of the test group indicated that the applied irrigation scheme was successful in maintaining improvements of periodontal health over a period of 6 months. There were no statistically significant differences in effectiveness between sites in molars and single-rooted teeth. On the other hand, negative controls treated only by a single root debridement procedure displayed a tendency towards pretreatment levels.

[Comparison of clinical and microbiological parameters for determination of actual caries risk]. / Vergleich klinischer und mikrobiologischer Parameter zur Bestimmung des aktuellen Kariesrisikos.

In 28 children and adolescents, age 4-17, the numbers of decayed tooth surfaces, filled surfaces and the extent of plaque coverage measured with a plaque scoring index were recorded as clinically assessible caries risk factors. Subsequently paraffin stimulated saliva samples were taken from the same subjects and evaluated microbiologically for their content of caries related microorganisms (S. mutans, lactobacilli). Statistical analysis of correlation revealed only weak, mostly not significant correlations between clinical and microbiological findings. The results are discussed.

[Effects of orthodontic treatment on individual caries risk parameters]. / Der Einfluss kieferorthopädischer Behandlung auf Parameter des individuellen Kariesrisikos.

Systemic and microbiological caries risk factors were assessed in 49 children and adolescents, age 11-14. The subjects were divided into three groups with similar age profiles. At the time of investigation members of test group 1 (n = 19) were receiving orthodontic therapy with removable appliances. Members of test group 2 (n = 15) were treated with fixed appliances and the control group (n = 15) had not been subjected to any kind of orthodontic treatment at all. The results demonstrate, that patients undergoing orthodontic treatment with fixed appliances harbor significantly more salivary S. mutans and therefore are at a higher microbiological risk to develop caries than patients being treated with removable appliances or individuals receiving no orthodontic treatment at all.

Localization of chondroitin sulphate and dermatan sulphate in human dental pulps--an immunohistochemical study.

The distribution of dermatan sulphate and chondroitin sulphate in human dental pulps has been assessed using monoclonal antibodies and immunoperoxidase localization techniques. The pulpal tissues were reacted with specific antibodies following pretreatment of the sections with chondroitinase ACII or chondroitinase ABC. Both the 4- and 6-sulphates isomers of chondroitin sulphate were detected in the tissues studied. Very little dermatan sulphate could be detected. These glycosaminoglycans appeared throughout the pulpal connective tissues with a particularly strong localization to the region adjacent to the odontoblastic and predentine layers. Such distribution strongly implicates chondroitin sulphate in the mineralization process of human dentine.

Subgingival irrigation in the maintenance phase of periodontal therapy.

The purpose of this study was to evaluate the effect of subgingival scaling versus subgingival pocket irrigation with 0.1% chlorhexidine or saline controls on the repopulation of subgingival periodontal sites with disease-associated micro-organisms following a single procedure of scaling and root planing. Additionally, pertinent clinical parameters (attachment level, plaque index, bleeding on probing) were also recorded. 375 sites in 30 individuals with previously untreated periodontal disease were thoroughly scaled and subsequently either rescaled, irrigated, or not treated at all for the following 6 months at 1-month intervals. The results show that the initial scaling and root planing procedure led to significant clinical and microbiological improvements in all experimental groups. These improvements were maintained in all but the untreated sites. Based on the observed clinical and microbiological changes, subgingival irrigation of periodontal pockets at 1-month intervals was equally effective as scaling and root planing performed at the same pace. 0.1% chlorhexidine however, being used as test irrigant, was not more effective than saline controls.

Repeated subgingival oxygen irrigations in untreated periodontal patients.

The aim of this study was to assess the effect of repeated subgingival oxygen irrigations in previously untreated deep periodontal pockets. 112 pockets > or = 4 mm were selected in 14 subjects. Probing attachment level and bleeding on probing were recorded, as well as the presence of disease-associated micro-organisms within the pocket. Subsequently, the pockets were irrigated with gaseous oxygen 1 x a week during a continuous 8-week period. Irrigations with nitrogen served as control. The re-evaluation of all clinical and microbiological parameters at the end of study revealed that repeated oxygen insufflations resulted in a significant clinical improvement of the periodontal baseline conditions superior to the one found in the control.

Effect of chlorhexidine-containing varnish (Cervitec) on microbial vitality and accumulation of supragingival dental plaque in humans.

The effect on local plaque formation of a varnish containing 1% chlorhexidine and 1% thymol (Cervitec) was evaluated. Ten volunteers with clinically healthy oral conditions were asked to refrain from any kind of oral hygiene measures for three periods of three days. Undisturbed plaque formation was recorded during the first experimental period. At the beginning of the second period, the varnish was applied to six vestibular enamel surfaces and removed after 1 h. The third experimental period was initiated 12 weeks after varnish application to assess a potential long-term effect. During each period of plaque formation, samples were collected from the vestibular surfaces after 24 h (from teeth 15/25), after 48 h (from teeth 14/24) and after 72 h (from teeth 13/23), respectively, and evaluated for total microscopic bacterial counts (BC) and colony forming units (CFU). Microbial vitality was assessed by the plating efficiency [PE = (CFU/BC) x 100] and directly by a vital fluorescence (VF) technique. VF of 48- and 72-hour plaque was significantly reduced after Cervitec application. An inhibitory effect by Cervitec could not be discerned 12 weeks after varnish treatment.

Microbial generation time during the early phases of supragingival dental plaque formation.

The objective of this investigation was to determine the microbial generation time during early human supragingival plaque formation. On 2 occasions, 13 participants refrained from all oral hygiene measures for periods of 1, 2, 4, 8, 24 and 72 h. Plaque was sampled from defined areas of the teeth 13, 14, 15, 23, 24 and 25. Two independent methods were used to estimate the total number of viable cells: colony-forming units BCVF, total bacterial counts (BC) as enumerated by microscopic examination, and the percentage of vital bacteria using a vital fluorescence technique (VF) were recorded. The total number of vital microorganisms was calculated by BCVF (= BC x VF). The generation time based on either colony-forming units or BCVF increased significantly with plaque age. During the first interval (1-4 h), the microbial multiplication took slightly less than 1 h. After the establishment of a more mature plaque (24-72 h), the replicating time was between 12.5 h (BCVF) and 14.8 h (colony-forming units). It was concluded that the microbial generation time recorded at the initial stages of plaque formation is considerably lower than that found in older plaque.

The efficacy of a single pocket irrigation on subgingival microbial vitality.

The object of this study was to monitor the proportion of vital bacteria (microbial vitality: VF in %) present in subgingival dental plaque following one single subgingival irrigation with saline (S), chlorhexidine (CHX) or povidone iodine (I2), but without any subgingival instrumentation. Its effect on the main composition of the microflora was also assessed. Seventeen patients with adult periodontitis took part in this investigation. In each patient four initially untreated pockets (pocket depth 5-11 mm) associated with bleeding were selected for the standardised pocket irrigation and plaque sampling at baseline (0 h) and after the following 1 h, 24 h, 7 days and 31 days. The subgingival irrigation was only performed once (0 h). One pocket per quadrant was irrigated using 0.9% prereduced S, 0.2% CHX or 0.05% I2 (Iso-Betadine Buccale). The remaining untreated pocket without any irrigation served as an additional control (C). Using an acrylic splint as a guide, paperpoints were inserted into the pocket precisely at the same site to collect subgingival plaque. The bleeding on sampling (BOS) was thereafter noted. The proportions of bacterial morphotypes were examined by darkfield microscopy. VF was evaluated using a vital fluorescence staining. The undisturbed subgingival dental plaque was composed of 86% (median value) vital bacteria. The sampling procedure alone and the saline irrigation led to a decrease in the number of spirochetes but had no influence on the vitality of the flora. Large variations in VF could be observed in the short-term (1 h, 24 h) irrigation effect of CHX and I2. The reduction of VF was still significant after 7 days (VF(CHX) 30-80%, VF(I2) 35-80%) but persisted up to 31 days only after I2 irrigation (VF(I2) 12-90%). The findings indicated that all single subgingival irrigations resulted in a temporary change of the subgingival microflora while povidone iodine produced the longest lasting antimicrobial effect. Any clinical advantage of this situation should be further investigated.