Randomized multicenter study on the plaque removal efficacy of 2 interdental brushes around the base of orthodontic brackets.

INTRODUCTION: The objective of this multicenter study was to analyze the efficacy of cleaning 2 interdental brushes (IDBs) around brackets in patients with fixed orthodontic appliances. METHODS: The study design was a multicenter, randomized, examiner-blinded crossover study with 3 interventions, the first of which was a baseline intervention. This study included 20 patients (12 females, 8 males) aged 12-18 years with fixed orthodontic devices examined at the Department of Orthodontics, University Medical Center of the Johannes Gutenberg University Mainz, and the Children's Dental Clinic St. Gallen. The outcome was a conventional, cylindrically shaped IDB (IDBG-S [IB]; Top Caredent GmbH, Schönau, Germany) was examined in comparison with an innovative waist-shaped IDB (Circum, CDB-8 [CB]; Top Caredent GmbH). The participants did not use the IDB themselves. The brushing procedure was performed professionally by 1 operator (C.E.). Each buccal tooth surface with a bracket was split into 8 areas, the main areas being 1 and 8. These main areas, which were difficult for toothbrushes to reach, were mesial (area 1) and distal (area 8) of the bracket edges in the gingival direction. Plaque index (PI) scores were assessed at 2 examinations before and after the cleaning procedure on 8 tooth surfaces in the area with orthodontic brackets. A computer-generated program randomly allocated the IDB sequence to the participants. Examiners (L.Z.-G. and Y.W.) assessing the outcomes were blinded to the intervention and the randomized allocation of participants to the different IDBs. RESULTS: Both IDBs showed a plaque removal effect (CB, 0.68 [interquartile range, 0.63-0.77]; IB, 0.43 [interquartile range, 0.33-0.55]). The difference between the 2 IDB was statistically significant (P = 0.002). In particular, the CB yielded a higher plaque removal efficacy (CB effect, 0.68; IB effect, 0.21) at the main areas 1 and 8, which were difficult to reach. Ten participants were randomized to each sequence, and all 20 completed the study. No side effects or adverse events were reported or observed. CONCLUSION: The waist-shaped brush head of the CB significantly enhanced plaque reduction in total and particularly in problem areas. REGISTRATION: This trial was registered at the German Clinical Trials Registry (no. DRKS00014088; https://www.drks.de/drks_web/navigate.xxdo?navigationId=trial.HTML&TRIAL_ID=DRKS00014088) PROTOCOL: The protocol was not published before trial commencement. FUNDING: This study was supported by the manufacturer Top Caredent GmbH, Schönau, Germany, which provided all interdental brushes used in this study.

Routine Data Analyses for Estimating the Caries Treatment Experience of Children.

Oral health surveys are considered the gold standard for assessing the caries experience of children. Analyses of routine data offer additional opportunities not yet fully explored. This study aimed at estimating the caries treatment experience by mining an insurance claims database. Comprehensive claims data sets were extracted from the data warehouse of a major health insurance company (BARMER, Germany). A surrogate variable for caries experience was formed that reflected the proportion of children without any former potentially caries-related treatment (filling, root canal treatment, and extraction) at ages from 1 to 14 years. The statistical calculations were based on Kaplan-Meier survival analyses. The evaluation for the permanent dentition comprised N = 593,330 children at 6 years and N = 114,568 at 12 years. At 12 years of age, 66.8% had not yet experienced potentially caries-related treatments. This value hints at a significantly higher caries experience at 12 years compared to available epidemiological data. For the deciduous dentition, the respective rates were 74.0% at 6 years and 45.8% at 10 years. Although various sources of bias have to be taken into account, the potential of routine data mining is evident. The approach is supplemental to oral health surveys. It can be useful in coming closer to reality when estimating the caries experience of children. From our results, we conclude that the oral health of up to 14-year-olds in Germany remains in urgent need of improvement.

Influence of a programme for prevention of early childhood caries on early orthodontic treatment needs.

OBJECTIVES: The aim of this prospective birth cohort study was to evaluate the effect of the programme for prevention (PP) of early childhood caries and the resulting need for orthodontic treatment in 8-year-old German children. MATERIAL AND METHODS: Children who had been enrolled in a caries-risk-related recall system with continuous dental care starting at the time of birth (prevention group, PG) were compared with children of the same birth cohort whose parents decided not to participate in the programme (control group, CG). All children (n = 289) participating in the last PP evaluation at the age of 5 years were invited again and examined by blinded clinicians. Dental caries was scored using the WHO diagnostic criteria expanded to d1-level without radiography. Impressions were taken of children with premature tooth loss to analyse space conditions. RESULTS: Two hundred twenty-seven children (mean age 8.4 ± 0.6 years; 46.7% female) were examined. Children in the PG (n = 127) showed significantly lower caries prevalence and experience (3.1%, 0.4 ± 1.0 d3-4mft) than children in the CG (37.3%, 3.9 ± 3.5 d3-4mft). Orthodontic analysis found a higher prevalence of premature tooth extraction, followed by a greater extent of space loss in the CG (41.0%; 3.3 ± 4.4 mm) vs. PG (7.9%; 0.4 ± 1.9 mm) and an increase in early orthodontic treatment need (KIG P3, IOTN 5). CONCLUSIONS: The PP was an effective approach for preventing caries-related premature tooth loss in children and conserving relevant arch length. CLINICAL RELEVANCE: Children who received continuous dental care starting at the time of birth showed better oral health with less premature loss of deciduous teeth and lower need for orthodontic treatment at the age of 8 years. TRIAL REGISTRATION: German Clinical Trials Register DRKS00003438, https://drks-neu.uniklinik-freiburg.de/drks_web/navigate.do?navigationId=trial.HTML&TRIAL_ID=DRKS00003438.

Qualitative and quantitative changes in the oral bacterial flora occur shortly after implementation of fixed orthodontic appliances.

INTRODUCTION: In this pilot study, we aimed to determine qualitative and quantitative microbiological changes after the implementation of orthodontic appliances. METHODS: A total of 10 healthy patients aged 12-15 years were recruited who needed to undergo orthodontic treatment with buccal fixed appliances. Gingival conditions were assessed by the Gingival Index, Periodontal Screening Index, and Sulcus Bleeding Index. Microbiological samples were collected before and 1 week after the start of therapy at premolars and molars of the right upper quadrant. Bacterial species were identified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. RESULTS: The total number of bacteria increased. Six bacterial species were identified that are involved in the development of caries and other infectious processes. The bacteria selectively adapted more efficiently to the new oral milieu compared with the general oral microbial background. There was a significant increase in Streptococcus spp at the premolars and molars. In all individuals, symptoms of inflammation and gingivitis were detected as a response to the bacterial challenge. CONCLUSIONS: Orthodontic treatment induces significant changes in the oral microbial flora associated with gingivitis and an enhanced risk for cariogenic reactions within the first days of orthodontic treatment. To prevent or reduce infectious side effects, oral hygiene instructions and control of patients are necessary before and during the beginning of the therapy.

Caries Prevalence and Risk Assessment in Thuringian Infants, Germany.

PURPOSE: To determine the caries prevalence and experience in Thuringian infants and to assess their caries risk. MATERIAL AND METHODS: The subjects were participants in a regional preventive programme, a birth cohort study with the aim of preventing caries. In the first year of life, children were invited to a dental examination at the Jena University Hospital. Dental caries was scored using WHO diagnostic criteria at the d1-level without radiography. Children were categorised as being of low, moderate or high risk for caries according to the caries-risk assessment tool of the American Academy of Pediatric Dentistry (AAPD). RESULTS: 512 children (mean age 6.7 ± 2.2 months) were examined. 58.2% (n = 298) of all children had teeth (2.21 ± 2.76). Caries prevalence of cavitated carious lesions was 1.7%, and prevalence of non-cavitated carious lesions was 7.7% in children who had teeth. Caries experience was 0.3 ± 1.0 d1-4mfs/0.2 ± 1.5 d3-4mfs (range of 0 to 16). Children with caries were on average 10.8 ± 3.2 months old, while children without caries were 6.6 ± 2.1 months. One hundred sixty-nine children (33.1%) were categorised at high risk for caries, and 98 already had teeth. CONCLUSION: Although caries prevalence and experience was relatively low in infants, one third of all children were categorised as being at high caries risk. Early dental visits are necessary to detect the first signs of caries, to assess the caries risk and to establish a dental home with a risk-related recall system. The caries-risk assessment tool (CAT) of the AAPD can assist the clinician in the decision-making process.

Evaluation of an interdisciplinary preventive programme for early childhood caries: findings of a regional German birth cohort study.

OBJECTIVES: The aim of this prospective birth cohort study was to evaluate the effect of the interdisciplinary preventive programme (PP) for early childhood caries in 3-year-old children in Germany. MATERIAL AND METHODS: From July 2009 to October 2010, all parents of newborns (n = 1162) were visited after birth by the communal newborn visiting service of Jena, Thuringia, and advised on general and dental health. In the first year of life, children were invited to a dental examination in Jena University Hospital. Participating children were included in a risk-related recall system with continuous oral care over 3 years. Caries-risk assessment tool of the AAPD was used for risk categorizing. High-risk children received fluoride varnish biannual. In 2013, the total birth cohort (participants and non-participants) was invited to evaluate the PP. Dental caries was scored using WHO diagnostic criteria expanded to d1-level without radiography. Data were analysed statistically (multivariate logistic regression). RESULTS: Seven hundred fifty-five children (mean age 3.26 ± 0.51 years) were examined. Children in the PP (n = 377) showed significantly lower caries prevalence and experience than non-participants (15.6 vs. 37.8 %, 0.9 ± 3.3 d1-4mfs vs. 2.6 ± 5.2 d1-4mfs). Lack of vitamin D supplements (OR = 1.9, CI 0.99-3.51), familial caries experience (OR = 2.2, CI 1.27-3.73) and visible plaque on teeth (OR = 6.5, CI 4.41-9.43) were significant risk factors for caries development, whereas regular dental care (OR = 0.5, CI 0.38-0.79) had a protective effect. CONCLUSIONS: The PP was an effective interdisciplinary approach for preventing early childhood caries in small children. CLINICAL RELEVANCE: Early dental visits with caries-risk-related preventive dental care are necessary to prevent early childhood caries (ECC). TRIAL REGISTRATION: German Clinical Trials Register DRKS00003438, https://drks-neu.uniklinik-freiburg.de/drks_web/navigate.do?navigationId=trial.HTML&TRIAL_ID=DRKS00003438.

Developmental defects of enamel in primary teeth - findings of a regional German birth cohort study.

BACKGROUND: The aim was to assess the prevalence, distribution and associated risk factors of developmental defects of enamel (DDE) in 3-year-old Thuringian children in 2013 as part of a prospective cohort study. METHODS: The subjects (n = 377) were all participants in a Thuringian oral health programme. Children of the birth cohort 2009/2010 were invited to dental examination in the first year of life, followed up with continuous dental care over the next 3 years. Dental caries was scored using the WHO diagnostic criteria expanded to the d1-level without radiography. Enamel defects were assessed according to the modified DDE Index. Data were analysed statistically (multivariate logistic regression). RESULTS: The children were aged 3.3 ± 0.7 years and 52.5 % of them were male. Caries prevalence was 15.6 % and caries experience 0.9 ± 3.3 d1-4mfs. The prevalence of DDE was 5.3 % with an average of 2.7 (±1.4) affected teeth. Second primary molars were the most affected teeth and demarcated opacities the most prevalent type. No child had Amelogenesis imperfecta and six children showed hypomineralised second primary molars. Enamel defects were associated with preterm birth (p = 0.024; OR = 4.9) and hospitalisation in the first year of life (p = 0.013; OR = 4.6). CONCLUSION: A relatively small proportion of 3-year-old Thuringian children suffered from DDE, with second primary molars as the most affected teeth and demarcated opacities as the most prevalent type of defect. Preterm birth and hospitalisation in first year of life can be considered as risk factors for DDE in the primary dentition. TRIAL REGISTRATION: German Clinical Trials Register, DRKS00003438.

Midwives' oral health recommendations for pregnant women, infants and young children: results of a nationwide survey in Germany.

BACKGROUND: Studies suggest that poor oral health during pregnancy can lead to perinatal complications, such as low birth weight and preterm delivery as well as poor oral health in children. Aim of this study was to assess the German midwives knowledge about oral health and preventive recommendations for pregnant women, infants and young children. METHODS: The nationwide online-survey was conducted with use of a self-developed, pretested and validated standardized questionnaire. The German association of midwives (Deutscher Hebammenverband e.V.) informed their members about the survey through email, newsletter, website and association journal (Hebammenforum) (n = 7.500). Data were analyzed using descriptive statistics. RESULTS: Response rate was 12.6 % (mean age 42.9 ± 9.3 years). The majority of midwives advised pregnant women about periodontal diseases (78.6 %). Of the midwives, 8.4 % mentioned the possible associations between periodontal diseases and perinatal complications. In general, half of the midwives (53.5 %) recommended a dental visit during pregnancy. A total of 65.5 % of midwives advised parents about early childhood caries. The majority of midwives recommended that oral hygiene starts with eruption of the first tooth (60.4 %) and the first dental visit of the child should be at age 2 or 3 years (51.6 %). Midwives recommendations regarding the implementation of oral hygiene and the referral to a dentist during pregnancy and childhood were highly variable. CONCLUSIONS: To increase oral awareness and to improve the oral health knowledge among midwives and all other health-care professionals, uniform guidelines should be developed in Germany. TRIAL REGISTRATION: German Clinical Trial Register DRKS00008021.

Occlusal characteristics in 3-year-old children--results of a birth cohort study.

BACKGROUND: Aim of this prospective study was to determine prevalence of malocclusion and associated risk factors in 3-year-old Thuringian children. METHODS: Subjects (n = 377) were participants in a regional oral health programme, a birth cohort study with the aim to prevent caries (German Clinical Trials Register DRKS00003438). Children received continuous dental care since birth. Occlusal characteristics (overjet, overbite, anterior open bite, canine relationship and posterior crossbite) were measured at the age of 3 years by one calibrated clinician using a vernier caliper (accuracy 0.1 mm; Münchner Modell 042-751-00, Germany). A regular parent survey was conducted to assess risk factors for development of malocclusion. RESULTS: Three hundred seventy seven children (mean age 3.31 ± 0.70 years; 52.5% male) were examined. Children had a mean overjet of 2.4 ± 0.8 mm and the mean overbite was 0.8 ± 1.2 mm; 58.8 % of the children had a normal overjet ≤ 3 mm and 88.8% a normal overbite with < [Formula: see text] overlap. Prevalence of malocclusion was 45.2% (10.9% anterior open bite, 41.2% increased overjet ≥ 3 mm, 40.8% Class II/III canine relationship, 3.4% posterior crossbite). All children who sucked the thumb had a malocclusion. Children who used a pacifier had greater odds of having a malocclusion at age of 3 years than children without pacifier use (OR = 3.36; 95% CI: 1.87-6.05). Malocclusion and dental trauma were associated, but not statistically significant (OR = 1.83; 95% CI: 0.99-3.34; p = 0.062). Malocclusion was not associated with gender, migration background, low socioeconomic status, preterm birth, special health care needs, breathing or dietary patterns (p > 0.05). CONCLUSIONS: Non-nutritive sucking habits were important risk factors for development of a malocclusion in the primary dentition.

Pediatricians' oral health recommendations for 0- to 3-year-old children: results of a survey in Thuringia, Germany.

BACKGROUND: German societies of pediatricians and dentists disagree about oral health-related preventive recommendations (use of fluoride supplements, fluoride-containing toothpaste) for children aged 0-3 years. After failure to reach a consensus, there is no study that has evaluated the guidelines that pediatricians use in daily practice. METHODS: A standardized questionnaire was sent to all 167 practicing pediatricians in the state of Thuringia, Germany, to assess the current oral health-related preventive recommendations. Data were analyzed using descriptive statistics. RESULTS: The response rate was 52.0%. More than 9.0% of the pediatricians advise parents with regard to diet, use of baby bottles, oral hygiene and dental visits. The majority of pediatricians recommend to start tooth-brushing after the 1st birthday and recommend the use of toothpaste and a 1st dental visit after the 2nd birthday (78.0%). Additionally, 23.3% (n = 20) of pediatricians prescribe solely vitamin D, and 20.9% (n = 18) prescribe vitamin D combined with fluoride. Fluoride supplements are given as required by 37.2% (n = 32) of pediatricians, primarily between the 1st and 6th birthdays. The guidelines of the Pediatric Society were used by 1.2% of the pediatricians, the guidelines of the dentists were used by 5.8%, and a mix of both was used by 93.0%. The simultaneous use of fluoride supplements and fluoride toothpaste in the first three years was recommended by 45.9% of the pediatricians. CONCLUSIONS: Pediatricians' oral health recommendations are based on a mix of the guidelines from the German societies of pediatricians and dentists and led to no use or possible overdose of fluoride. Against the background of early childhood caries and dental fluorosis, there is a need for uniform guidelines.

Effect of using different component combinations for orthodontic bracket bonding with self-etch primers.

PURPOSE: To evaluate bonding quality for orthodontic bracket bonding with different component combinations of self-etch primers in vitro. METHODS: Metallic brackets were bonded to bovine lower incisors and assigned to groups. Group 1: comparison of self-etch (Transbond™ Plus, 3M™ Unitek, Neuss, Germany, n = 30; BrackFix® primer SE, VOCO®, Cuxhaven, Germany, n = 20) and etch-and-rinse bonding systems (Transbond™ XT, n = 20; BrackFix®, n = 20); group 2: comparison of different self-etch primer (Transbond™ Plus; BrackFix® primer SE) and adhesive (Transbond™ XT, n = 20; BrackFix®, n = 20) product combinations; group 3: testing cyclic fatigue bond strength of self-etch bonding systems (Transbond™ Plus, n = 20; BrackFix® primer SE, n = 20). All teeth were tested for shear bond strength according to the DIN-13990 standard, the adhesive remnant index (ARI) and enamel fractures were determined microscopically (10 נmagnification). RESULTS: The mean shear bond strength of the self-etch (Transbond™ Plus: 16.38 ± 3.68 MPa; BrackFix® primer SE: 16.24 ± 1.73 MPa) and etch-and-rinse bonding systems (Transbond™ XT: 18.45 ± 2.56 MPa; BrackFix®: 17 ± 5.2 MPa) were of a clinically adequate order of magnitude (≥ 6-10 MPa) and were not statistically different. The component combination BrackFix® primer SE/Transbond™ XT adhesive led to a significantly lower shear bond strength (11.99 ± 3.68 MPa). There were no significant differences between static and fatigue shear bond strengths of self-etch bonding systems. Mean ARI scores mostly ranged between 4 and 5. The combination of the self-etch primer Transbond™ Plus with the BrackFix® adhesive led to a significantly increased enamel fracture rate. CONCLUSIONS: Based on the present findings bond strength of self-etch primers was equal to etch-and-rinse primers for bracket bonding. Combining different self-etch bonding systems might alter the clinical performance.

Associations of early childhood medication exposure and molar incisor hypomineralization (MIH): A routine data analysis.

OBJECTIVES: Molar incisor hypomineralization (MIH) has become a major oral health problem of widely unknown origin. Besides genetic predisposition, exposure to certain drugs in early childhood are suspected to be associated with MIH. Aim of this routine data analysis was to examine associations of MIH and exposure to medication as well as perinatal factors. METHODS: Individuals with MIH were identified in claims data using a validated predefined specific treatment pattern. The database was a comprehensive routine data set of a major national health insurance company (BARMER, Germany). Based on this treatment pattern a MIH group and an unaffected control group were formed for analysis. Various medical data including medical diagnoses and prescriptions were available. Associations were examined comparing results for a set of variables in both groups. Differences between the groups were tested for significance using T-tests (P<0.01). RESULTS: Between 2010 to 2019, a total of 298,502 children between 6 and 9 years of age were included in this analysis. 22,947 were assigned to the MIH group. For individuals in this group, significantly larger prescription quantities in the main ATC (Anatomical, Therapeutic, Chemical) groups J (antiinfectives for systemic use), R (respiratory system) and S (sensory organs) were found in the first 4 years of life compared to MIH unaffected individuals. With antibiotics, there were both significantly larger prescription quantities and significantly higher numbers of respective prescriptions in the first 4 years of life. The differences amounted up to about 10.62% in frequently used antibiotics to be found in ATC J01D (other beta-lactam antibacterials) for the number of prescriptions in the 4th year of life. No association was found for premature birth, mode of delivery or the use of antipyretic or anti-inflammatory medication. CONCLUSIONS: While perinatal factors do not seem to be associated with MIH development, early life exposure to antibiotics might play a role. CLINICAL SIGNIFICANCE STATEMENT: Although causal relations can still not be proven, a responsible use of the unquestionably beneficial antibiotics is encouraged from a clinical point of view.

Simplifying Computer Aided Ergonomics: A User-Product Interaction-Modeling Framework in CAD Based on a Taxonomy of Elementary Affordances.

OCCUPATIONAL APPLICATIONSThis contribution provides a framework for modeling user-product interactions (in CAD) for in-depth ergonomic analysis of product design, using digital human models. The framework aims to be applicable to a wide range of different products while being suitable for designers - especially those who do not have specialized ergonomic expertise or training in human behavior - by providing an intuitive, standardized, and time-efficient modeling procedure. The framework contains 31 elementary affordances, which describe mechanical dependencies between product geometries and human end effectors. These elementary affordances serve as a tool for interaction modeling. Additionally, the paper provides a taxonomy of elementary affordances, which can be used to formalize / abstract the nature of user-product interactions and to describe them as elementary affordances. Furthermore, an implementation of the interaction-modeling framework is presented in a CAD environment and provides an example of how the framework could be used in terms of a computer aided ergonomics tool.

TECHNICAL ABSTRACTBackground Digital human models (DHM) have not yet reached their full potential for proactive virtual assessment of ergonomics in engineering and industrial design. Modeling the interaction between user and product often is time demanding, cumbersome, unstandardized, or embedded insufficiently in the computer aided engineering environment. Existing interaction-modeling frameworks either address the simulation of occupational processes, are limited to a specific use cases, or offer insufficient usability.Purpose We present a framework for interaction modeling, its methodic background, as well as its implementation. The framework aims to provide ergonomic analyses of product designs, while being suitable for designers who do not have specific ergonomic knowledge or training in human behavior.Methods To resolve these partly contradictable demands, we utilize affordances, which serve as a tool for interaction modeling. We hypothesize, that many interaction concepts existing in human technology interaction can be reduced to a relatively small set of elementary affordances. We developed a taxonomy of elementary affordances to deduce elementary affordances from empirical interaction data.Results We present the resulting taxonomy, as well as the resulting 31 elementary affordances, which describe mechanical dependencies between product geometries and human end effectors. The identified elementary affordances are implemented as affordance features in a CAD environment (Siemens NX) and result in an interaction-modeling framework. A brief application example regarding the functionalities of the framework is presented.Conclusions The introduced framework demonstrates how the integration of interaction modeling into the computer aided engineering environment can be achieved in a comprehensible and straightforward way. The resulting simplicity and accessibility may constitute one key factor to help exploit the potential of DHM simulation as a computer aided ergonomics tool in engineering and industrial design.

Analysing the potential of hydrophilic adhesive systems to optimise orthodontic bracket rebonding.

INTRODUCTION: Bond failure during fixed orthodontic treatment is a frequently occurring problem. As bracket rebonding is associated with reduced shear bond strength, the aim of the present investigation is to analyse the effect of different innovative rebonding systems to identify optimised rebonding protocols for orthodontic patient care. METHODS: Metallic brackets were bonded to the frontal enamel surfaces of 240 bovine lower incisors embedded in resin bases. Teeth were randomly divided into two major experimental groups: in group 1 a hydrophilic primer (Assure™ PLUS) was compared to commonly used orthodontic adhesives (Transbond XT™, BrackFix®, Grengloo™) and a zero control. In group 2 different rebonding systems were analysed using a hydrophilic primer (Assure™ PLUS), a methyl methacrylate-consisting primer (Plastic Conditioner) and a conventional adhesive (Transbond XT™). All teeth were tested for shear bond strength according to the DIN-13990 standard, the Adhesive Remnant Index and enamel fracture rate. RESULTS: The hydrophilic primer enhanced shear bond strength at first bonding (Assure™ PLUS 20.29 ± 4.95 MPa vs. Transbond XT™ 18.45 ± 2.57 MPa; BrackFix® 17 ± 5.2 MPa; Grengloo™ 19.08 ± 3.19 MPa; Meron 8.7 ± 3.9 MPa) and second bonding (Assure™ PLUS 16.76 ± 3.71 MPa vs. Transbond XT™ 13.06 ± 3.19 MPa). Using Plastic Conditioner did not seem to improve shear bond strength at rebonding (13.57 ± 2.94). When enamel etching was left out, required shear bond strength could not be achieved (Plastic Conditioner + Assure™ PLUS 8.12 ± 3.34 MPa; Plastic Conditioner: 3.7 ± 1.95 MPa). Hydrophilic priming systems showed decreased ARI-scores (second bonding: 2.63) and increased enamel fracture rates (first bonding: 55%; second bonding 21,05%). CONCLUSIONS: Based on the present study we found that rebonding strength could be compensated by the use of hydrophilic priming systems. The additional use of a methyl methacrylate-consisting primer does not seem to enhance shear bond strength. No etching approaches resulted in non-sufficient bond strength.

Tooth loss after periodontal treatment-Mining an insurance database.

OBJECTIVES: The aim of this study was to evaluate tooth loss after periodontal treatment. METHODS: The data was collected from the digital database of a major German national health insurance company. Periodontal treatment was the intervention in the treatment group. Kaplan-Meier survival analyses on the patient level with the primary outcome extraction were carried out over four years. A control group without treatment was matched and analysed. Differences were tested with the Log-Rank-test. Extraction incidences were calculated over a matched observation period six years before and four years after treatment for both treatment and control group. RESULTS: A total of 415,718 periodontal treatments could be traced. Focussing on the outcome "extraction", the cumulative four-year survival rate was 63.8% after periodontal treatment. The matched control group without periodontal treatment showed a survival rate of 72.5%. These differences were significant (p < 0.0001). The extraction incidence over time was higher in a four-year period after periodontal treatment compared to a six-year period before periodontal treatment. CONCLUSIONS: The outcome of periodontal treatment was acceptable. In about two thirds of the patients, extractions could be completely avoided within a four year period after treatment. CLINICAL SIGNIFICANCE STATEMENT: This study within the German national health insurance system shows that extractions were not observed after periodontal treatment in the majority of cases. Although periodontitis is a chronic disease, patients suffering from periodontitis have a considerable chance to prevent further tooth loss.

Risk factors for dental problems: Recommendations for oral health in infancy.

Primary care providers, gynaecologists and paediatricians have to be aware of the importance of oral health in infancy and possible consequences for child's development, growth, health and quality of life. Oral diseases, particularly dental caries, developmental defects of the dental tissues and periodontal or orthodontic issues have a complex and interrelated aetiology with common, primarily behavioral based risk factors. A sugar-rich diet is the key risk factor with detrimental consequences for general and oral health, particularly in combination with an insufficient oral hygiene. Therefore, daily tooth brushing with fluoride toothpaste and reducing of sugar intake are the key pillars to prevent oral diseases, including a positive effect on numerous chronic diseases. Future preventive approaches should focus on pregnant women and mothers of infants with a common vision of health and a shared responsibility for children's oral health care to promote healthy lifestyles and self-care practices in families.

Periodontopathogenic bacteria multiply in the environmental amoeba Acanthamoeba castellani.

Porphyromonas gingivalis and Prevotella intermedia are obligate anaerobe gram-negative periodontopathogenic bacteria. Free-living amoebae, such as Acanthamoeba spp., are well known as environmental hosts of several human pathogens, such as Franciscella tularensis, Chlamydia pneumoniae, Legionella pneumophila and Mycobacteria spp. This study tested the ability of P. gingivalis and P. intermedia to become internalized, to survive and replicate in Acanthamoeba castellani. Our results show for the first time that P. gingivalis and P. intermedia isolated from periodontitis patients are capable of infecting A. castellani cells in vitro and are able to survive and multiply intracellularly. From our experimental data it can be suggested that periodontopathogenic bacteria might be conditioned in the evolution by amoebae and free-living amoebae can act as an environmental reservoir for these pathogens.

Multidimensional nano-HPLC for analysis of protein complexes.

The analysis of macromolecular protein complexes is an important factor in understanding most cellular processes, e.g., protein transport into cell organells, signal transduction via biological membranes, apoptosis, energy metabolism, directed motion of cells, and cell division. These complexes are not only built of various numbers of different proteins but also of prosthetic groups and RNA molecules. To understand the role each protein plays in a complex, a complete analysis of all protein compounds is necessary. Therefore, several separation steps have to be coupled to mass spectrometry to identify the proteins. In this work, we describe the application of multidimensional liquid chromatography, SCX-RP-LC as well as SAX-RP-LC, coupled to electrospray ion trap mass spectrometry. Tryptic digested ribosomes were separated by ion exchange chromatography manually collected and prepared for reversed phase chromatography to analyze the peptides via nano-ESI mass spectrometry. The total numbers of identified proteins are compared in consideration of the separation method (SCX-RP versus SAX-RP).

Challenges in mass spectrometry-based proteomics.

During the last decade, protein analysis and proteomics have been established as new tools for understanding various biological problems. As the identification of proteins after classical separation techniques, such as two-dimensional gel electrophoresis, have become standard methods, new challenges arise in the field of proteomics. The development of "functional proteomics" combines functional characterization, like regulation, localization and modification, with the identification of proteins for deeper insight into cellular functions. Therefore, different mass spectrometric techniques for the analysis of post-translational modifications, such as phosphorylation and glycosylation, have been established as well as isolation and separation methods for the analysis of highly complex samples, e.g. protein complexes or cell organelles. Furthermore, quantification of protein levels within cells is becoming a focus of interest as mass spectrometric methods for relative or even absolute quantification have currently not been available. Protein or genome databases have been an essential part of protein identification up to now. Thus, de novo sequencing offers new possibilities in protein analytical studies of organisms not yet completely sequenced. The intention of this review is to provide a short overview about the current capabilities of protein analysis when addressing various biological problems.

The proteome of Saccharomyces cerevisiae mitochondria.

We performed a comprehensive approach to determine the proteome of Saccharomyces cerevisiae mitochondria. The proteins of highly pure yeast mitochondria were separated by several independent methods and analyzed by tandem MS. From >20 million MS spectra, 750 different proteins were identified, indicating an involvement of mitochondria in numerous cellular processes. All known components of the oxidative phosphorylation machinery, the tricarboxylic acid cycle, and the stable mitochondria-encoded proteins were found. Based on the mitochondrial proteins described in the literature so far, we calculate that the identified proteins represent approximately 90% of all mitochondrial proteins. The function of a quarter of the identified proteins is unknown. The mitochondrial proteome will provide an important database for the analysis of new mitochondrial and mitochondria-associated functions and the characterization of mitochondrial diseases.