Understanding the dual-task costs of walking: a StartReact study.

The need to perform multiple tasks more or less simultaneously is a common occurrence during walking in daily life. Performing tasks simultaneously typically impacts task performance negatively. Hypothetically, such dual-task costs may be explained by a lowered state of preparation due to competition for attentional resources, or alternatively, by a 'bottleneck' in response initiation. Here, we investigated both hypotheses by comparing 'StartReact' effects during a manual squeezing task under single-task (when seated) and dual-task (when walking) conditions. StartReact is the acceleration of reaction times by a startling stimulation (a startling acoustic stimulus was applied in 25% of trials), attributed to the startling stimulus directly releasing a pre-prepared movement. If dual-task costs are due to a lowered state of preparation, we expected trials both with and without an accompanying startling stimulus to be delayed compared to the single-task condition, whereas we expected only trials without a startling stimulus to be delayed if a bottleneck in response initiation would underlie dual-task costs. Reaction times of the manual squeezing task in the flexor digitorum superficialis and extensor carpi radialis muscle were significantly delayed (approx. 20 ms) when walking compared to the seated position. A startling acoustic stimulus significantly decreased reaction times of the squeezing task (approx. 60 ms) both when walking and sitting. Dual-task costs during walking are, therefore, likely the result of lowered task preparation because of competition for attentional resources.

Anterior Open Bite In 27 Months Old Children after Use of a Novel Pacifier - A Cohort Study.

OBJECTIVES: The aim of the present cohort study was to evaluate the influence of a novel pacifier on the first formation of malocclusion, the anterior open bite in children. STUDY DESIGN: 129 newborn children whose parents had decided to use pacifiers were randomly attributed to two experimental groups (D=Dentistar, n=56, Novatex, Pattensen, Germany; N=NUK, n=73, Mapa, Zeven, Germany). Children (n=42) who did not use a pacifier were not randomized and served as reference (C). Primary outcome was the presence of anterior open bite. It was hypothesized that D would result in lower incidence when compared to N. At the age of 27 months the children were examined with respect to anterior open bite. Fisher's exact test served to detect significant differences between groups D and N (SPSS 22.0). RESULTS: 121 children with a mean age of 26.7 months were included in the final analysis (D: n=45; N: n=42; C: n=34). In group D three children (6.7%) showed an anterior open bite. The respective values were 21 (50.0%) for N and 0 for C. The results for group D compared to N were significantly different (chi(2)-test, p<0.001). CONCLUSION: In comparison to a commonly used pacifier the novel one causes significantly less anterior open bites.

Efficacy of a novel pacifier in the prevention of anterior open bite.

PURPOSE: The purpose of this study was to test a novel pacifier (Dentistar) regarding the development of anterior open bite in infants. METHODS: One hundred twenty-nine newborn children were randomly assigned to 2 experimental groups: NUK (N; N =73); and Dentistar (D; N=56. Children (N=42) who did not use a pacifier served as the control (C). At 10- to 26-months old, the children were re-examined (via a blind operator) regarding the existence of an anterior open bite. RESULTS: One hundred twenty-one toddlers (66 females, 55 males) were included in the final analysis (N: N=42; D: N=43; C: N=36). The mean age was 15.9 (±3.9 SD) months. In Group N, 16 children (38%) showed an anterior open bite, 2 (5%) in Group D, and 0 in Group C. The incidence of open bites was significantly less in Groups D and C vs N (chi-square test, P<.001). No significant difference was found between D and C. CONCLUSION: Pacifier use may promote open bites in 16-month-old infants. Compared to a commonly used pacifier, the Dentistar caused almost no anterior open bites and, therefore, can be recommended for children younger than 16 months old.

Association between oral health-related and general health-related quality of life in subjects attending dental offices in Germany.

OBJECTIVES: To evaluate the GHRQoL and OHRQoL of patients attending dental offices in Germany and to determine correlation coefficients between SF (Short Form)-12 and OHIP (Oral Health Impact Profile)-14 scores. METHODS: A total of 10,342 dental offices were randomly selected. Each of the 1,113 that consented to participate received 20 questionnaires to be filled in by a convenience sample of the patients. The questionnaire included the OHIP-14-form for OHRQoL as well as the SF-12-form for GHRQoL. RESULTS: A total of 12,392 completed questionnaires were analyzed. The mean age of the participants (64.9 percent female, 35.1 percent male) was 44.25 years. The mean summary score of OHIP-14 was 6.30 (SD 7.46). The mean physical component summary scale (PCS) of the SF-12 was 51.15 (SD 7.23) and the mental component summary scale (MCS) was 50.17 (SD 8.55). The variance of PCS and MCS could be explained to 10 percent each by oral health-related quality of life (r2 = 0.095 and 0.101, P < 0.001). CONCLUSION: OHRQoL is considerably related to GHRQoL.

Long-term survival of Cerec restorations: a 10-year study.

This clinical retrospective study assessed the longevity of CAD-CAM ceramic restorations (Cerec) inserted into the cavities of 95 patients in a private practice in Berlin, Germany. Three hundred and eight ceramic restorations were inserted into cavities in the posterior teeth of 95 patients between 1992 and 1994. One operator placed all restorations in a single sitting. Seventy-four patients, including 226 restorations, returned to the practice for a final examination at the end of 10 years. Reasons for non-attendance include relocation (15), death (2) and personal reasons (4). Again, all examinations were performed by a single examiner, however, not the same dentist who initially treated the patients. Out of the 226 restorations, 39 had been inserted in Class I cavities and 187 in Class II cavities (84 two-surfaces, 103 three or more surfaces). In the latter group, one cusp was replaced in 20 cases and two cusps in three cases. All the restorations were fabricated using Cerec 1 (46 Dicor, 180 Vita Mark II) and cemented adhesively with Vita Cerec Duo Cement in combination with Syntac Classic under a rubber dam. Kaplan-Meier survival analysis was calculated under the following failure-criteria: (1) secondary decay, (2) any kind of loss of the restoration, (3) fracture of the restoration, (4) tooth fracture and (5) marginal gap reaching dentin or base material. For statistical analysis, SPSS 12.0 was used. The survival rate was 94.7% (12 failures) after five years and 85.7% (23 failures) after 10 years. The results of the current study show that the survival rate of Cerec 1 restorations, as applied in this study, are comparable with the survival rates of cast gold restorations.

The laser shoes: A new ambulatory device to alleviate freezing of gait in Parkinson disease.

OBJECTIVE: To assess, in a cross-sectional study, the feasibility and immediate efficacy of laser shoes, a new ambulatory visual cueing device with practical applicability for use in daily life, on freezing of gait (FOG) and gait measures in Parkinson disease (PD). METHODS: We tested 21 patients with PD and FOG, both "off" and "on" medication. In a controlled gait laboratory, we measured the number of FOG episodes and the percent time frozen occurring during a standardized walking protocol that included FOG provoking circumstances. Participants performed 10 trials with and 10 trials without cueing. FOG was assessed using offline video analysis by an independent rater. Gait measures were recorded in between FOG episodes with the use of accelerometry. RESULTS: Cueing using laser shoes was associated with a significant reduction in the number of FOG episodes, both "off" (45.9%) and "on" (37.7%) medication. Moreover, laser shoes significantly reduced the percent time frozen by 56.5% (95% confidence interval [CI] 32.5-85.8; p = 0.004) when "off" medication. The reduction while "on" medication was slightly smaller (51.4%, 95% CI -41.8 to 91.5; p = 0.075). These effects were paralleled by patients' positive subjective experience on laser shoes' efficacy. There were no clinically meaningful changes in the gait measures. CONCLUSIONS: These findings demonstrate the immediate efficacy of laser shoes in a controlled gait laboratory, and offer a promising intervention with potential to deliver in-home cueing for patients with FOG. CLASSIFICATION OF EVIDENCE: This study provides Class III evidence that for patients with PD, laser shoes significantly reduce FOG severity (both number and duration of FOG episodes).

Determination of the performance of various root canal disinfection methods after in situ carriage.

The aim of this study was to compare the antimicrobial performance of the Endox Endodontic System (Lysis Srl, Nova Milanese, Italy), MTAD (Dentsply Tulsa Dental, Tulsa, OK), sodium hypochlorite (NaOCl), and HealOzone (Kavo, Biberach, Germany). Seventy instrumented and initially sterile roots with open accesses and containing a paper point were carried by one volunteer in the oral cavity for 1 week. After removal, samples were taken for microbiological analysis. The root canals were then disinfected with the Endox Endodontic System, MTAD, 3% NaOCl, or HealOzone, and, thereafter, samples were repeated for microbiological analysis. The roots were then sealed and incubated for a further week, after which bacterial growth was again determined. After disinfection, there was a significant decrease in the absolute bacterial count between each disinfection method and the positive control group. There was no statistically significant difference between the NaOCl, MTAD, and HealOzone groups. The Endox device showed the least antibacterial effect with significant differences to MTAD and HealOzone. Bacterial regrowth after 1 week of incubation was detected in all samples of the control group, whereas test groups showed several bacteria-free samples.

Clinical efficacy of flossing versus use of antimicrobial rinses.

BACKGROUND: Dental floss is only used by a small part of the population on a daily basis. Therefore, an easy, applicable alternative is needed. This alternative could be a mouthrinse with antimicrobial activity for daily use. The aim of the present study was to evaluate the efficacy of two mouthrinses in reducing interdental plaque and gingivitis compared to dental floss. METHODS: A total of 156 healthy volunteers were randomly assigned to the following groups: 1) toothbrushing and rinsing (0.06% chlorhexidine and 0.025% fluoride); 2) toothbrushing and rinsing (0.1% cetylpyridiniumchloride and 0.025% fluoride); 3) toothbrushing and flossing; and 4) toothbrushing only (N = 39 subjects in each group). At baseline, the modified proximal plaque index (MPPI) and papillary bleeding index (PBI) were recorded. Thereafter, subjects had to brush in the usual manner during 8 weeks. Additionally, test groups had to rinse once a day (groups 1 and 2: 30 seconds) or to floss (group 3). Eight weeks after baseline, indices were recorded again and improvements were calculated. Analysis of variance (ANOVA) and the Bonferroni test served for statistical analysis. RESULTS: After 8 weeks, reductions for all indices were found in all groups (P <0.05). With respect to the MPPI, mouthrinse groups performed better than the control and floss groups: 1) 0.73; 2) 0.82; 3) 0.40; and 4) 0.32 (P <0.05). The PBI showed no statistically significant difference between groups: 1) 0.46; 2); 0.50; 3); 0.42; and 4) 0.37. CONCLUSION: The results suggest that, in combination with toothbrushing, daily use of the tested mouthrinses may result in a higher interproximal plaque reduction than daily flossing.

Bacterial leakage in roots filled with different medicaments and sealed with Cavit.

The aim of this study was to evaluate the time required by four different root canal medications coupled with the temporary filling material Cavit (ESPE, Seefeld, Germany) to prevent penetration of bacteria into the root canal. There were 145 roots prepared in a standardized manner. Four groups with 15 samples each were dressed with calcium hydroxide (Ca(OH)(2)), a 5% chlorhexidine gel (CHX), a chloromono-campherphenolic compound (ChKM), and Ledermix (LM), respectively, and sealed with Cavit. Four control groups contained identical medications but the roots were left unsealed. The 25 remaining roots served as additional controls. A standard setup for bacterial leakage studies was chosen with Staphylococcus epidermidis as test strain. Cavit application resulted in a significantly better seal compared with the unsealed groups. In the Cavit-sealed groups, all groups differed significantly from one another except for the CHX and the ChKM groups. The Ca(OH)(2) medicated roots provided the longest protection (median of 36 days), followed by the Ledermix-group (27 days) and the CHX (18 days) or ChKM groups (19 days). It may be concluded that Cavit-sealed and medicated root canals do not provide adequate protection against bacterial leakage for more than 1 month.

The Practicalities of Assessing Freezing of Gait.

BACKGROUND: Freezing of gait (FOG) is a mysterious, complex and debilitating phenomenon in Parkinson's disease. Adequate assessment is a pre-requisite for managing FOG, as well as for assigning participants in FOG research. The episodic nature of FOG, as well as its multiple clinical expressions make its assessment challenging. OBJECTIVE: To highlight the available assessment tools and to provide practical, experience-based recommendations for reliable assessment of FOG. METHODS: We reviewed FOG assessment from history taking, questionnaires, lab and home-based measurements and examined how these methods account for presence and severity of FOG, their limits and advantages. The practicalities for their use in clinical and research practice are highlighted. RESULTS: According to the available assessment tools severity of FOG is marked by one or a combination of multiple clinical expressions including frequency, duration, triggering circumstances, response to levodopa, association with falls and fear of falling, or need for assistance to avoid falls. CONCLUSIONS: To date, a unique methodological tool that encompasses the entire complexity of FOG is lacking. Combining methods should give a better picture of FOG severity, in accordance with the precise clinical or research context. Further development of any future assessment tool requires understanding and thorough analysis of the specific clinical expressions of FOG.

New systematically modified vesamicol analogs and their affinity and selectivity for the vesicular acetylcholine transporter - A critical examination of the lead structure.

To verify vesamicol as lead structure in the development of radioligands for imaging of VAChT in the brain by PET, we systematically modified this molecule and investigated four different groups of derivatives. Structural changes were conducted in all three ring systems A, B, and C resulting in a library of different vesamicol analogs. Based on their in vitro binding affinity toward VAChT as well as σ1 and σ2 receptors, we performed a structure-affinity relationship (SAR) study regarding both affinity and selectivity. The compounds possessed VAChT affinities in the range of 1.32 nM (benzovesamicol) to >10 µM and selectivity factors from 0.1 to 73 regarding σ1 and σ2 receptors, respectively. We could confirm the exceptional position of benzovesamicols as most affine VAChT ligands. However, we also observed that most of the compounds with high VAChT affinity demonstrated considerable affinity in particular to the σ1 receptor. Finally, none of the various vesamicol analogs in all four groups showed an in vitro binding profile suitable for specific VAChT imaging in the brain.

Relationship of radiologic and histologic signs of inflammation in human root-filled teeth.

The aim of this study was to determine the relationship between histologic and radiologic signs of inflammation in human root-filled teeth. In addition, other factors with possible importance for apical inflammation were assessed. Fifty-three block sections of root-filled teeth were gathered from human cadavers. The blocks were radiographically exposed, sectioned, and stained with hematoxylin and eosin. Histologic sections were categorized as inflamed or uninflamed. Radiographically, the roots were assigned as apical lucency, widened periodontal ligament (PDL), or no lucency. Presence and contents of accessory canals were recorded (empty, tissue, or filling material). Statistical analysis was performed with the Chi-square test. All roots had accessory canals; 12 showed tissue remnants, and the others were empty. Of the cases, 49% were histologically uninflamed at the apex, and 52% appeared radiographically intact. The odds ratio of finding a histologically inflamed apex with radiologic lucency versus a radiographically intact apex was 9.2 (p = 0.002). The odds ratio of finding a histologically uninflamed apex with a radiologically tight coronal seal versus an unacceptable seal was 3.7 (p = 0.053). It may be concluded that there are relationships between radiologic and histologic signs of inflammation in human root canal-treated teeth. There appears to be a tendency that the radiologically determined quality of the coronal seal has an impact on the histologic state of the root-filled tooth. No relationship was detected between unfilled lateral or accessory canals and the status of inflammation at the periapex (51% inflamed, 49% uninflamed).

In situ antimicrobial effectiveness of chlorhexidine and calcium hydroxide: gel and paste versus gutta-percha points.

The aim of this study was to determine the antibacterial effectiveness of either chlorhexidine or calcium hydroxide integrated in gutta-percha points compared with chlorhexidine or calcium hydroxide delivered as gel or paste, respectively. A total of 70 initially sterile roots with open accesses were carried for 1 week in the oral cavities of two volunteers. The roots were then removed, and samples were taken from the root canals for microbial analysis. The roots were medicated with calcium hydroxide paste, 5% chlorhexidine gel, or a chlorhexidine- or calcium hydroxide-containing gutta-percha point. The accesses were closed with bonding material, and the roots incubated for 1 week. After removal of the antimicrobial agents, roots were again checked for bacterial growth. One thioglycolate-soaked paper point was then introduced into each canal, and roots were incubated for 1 week more to observe bacterial regrowth. After 1 week of medication, the absolute bacterial count revealed significant differences compared with the controls. However, only the chlorhexidine-gel and the calcium hydroxide paste group showed no microbial colonization in a considerable number of samples after 1 and 2 weeks.

Clinically controlled study on the quality of class III, IV and V composite restorations after two years.

PURPOSE: The quality of fillings consisting of a hybrid composite was compared with fillings consisting of two different microfilled composites in a clinical examination. MATERIAL AND METHODS: Within the design of a clinically controlled two-year study conducted under practice-relevant conditions, the composites C-Fill MH (Megadenta), Helio Progress (Vivadent), and Visio-Dispers (ESPE) were examined in anterior-tooth cavities in 134 patients by means of the split-mouth technique. The clinical examinations were performed based on modified Ryge criteria (marginal integrity, anatomical form, secondary caries, color, marginal discoloration, surface roughness) after 12 and 24 months. RESULTS: Immediately following filling application, all evaluation criteria except color were assessed as level A. After 12 and 24 months, C-Fill MH was found to be significantly superior to the other materials with regard to marginal integrity, color, and marginal discoloration. CONCLUSION: The hybrid composite C-Fill MH seems to be superior to the microfilled composites and should therefore be preferred as a restorative filling material.

Enamel fluoride retention after application of fluoride-containing rubber cups.

PURPOSE: To compare the fluoride retention in bovine enamel after using fluoride-containing rubber cups or a conventional rubber cup in combination with a fluoride-containing polishing paste. MATERIALS AND METHODS: From each of 20 bovine incisors, 5 enamel slabs with a diameter of 3 mm were sectioned and assigned to 5 groups (A,B,C,D,E). Group A was left untreated and served as the negative control. Group B was polished with a rubber cup combined with a fluoride-containing prophylaxis paste for 10 s (Hawe Cleanic). Groups C and D were treated in the same manner by using a fluoride-containing rubber cup with 2,262 ppm or 9,048 ppm fluoride as NaF. Group E enamel was brushed for 10 s with a toothbrush and a slurry of distilled water and fluoride gel with 12,500 ppm fluoride as NaF and AmF (Elmex Gelee) and served as the positive control. Th e specimens were analyzed using the method of Caslavska et al. After determining the KOH soluble fluoride on the enamel surface, the content of structurally bound fluoride was analyzed in three consecutive layers of 30 microm. ANOVA with Bonferroni correction was used for statistical analysis (P< 0.05). RESULTS: For the KOH-soluble fluoride, Groups B and D accumulated more KOH-soluble fluoride than the negative control and less than the positive control. With respect to the structurally bound fluoride, the accumulation in Group D was higher when compared to all other groups. It was concluded that a rubber cup with 9,048 ppm fluoride may be an effective alternative to the use of a fluoride-containing prophylaxis paste.

Recommendations for the use of fluoride in caries prevention.

From a theoretical point of view, caries can be prevented by perfect oral hygiene and sugar abstinence. However, practice has shown that this approach is successful in individual cases only. For the whole population, effective caries prevention is still not realistic without the use of fluoride in various forms. The use of different fluoride preparations increases its efficacy. On the other hand, correct dosage is important to prevent the risk of dental fluorosis. Most of the European scientific dental associations no longer recommend the use of fluoride supplements, such as fluoride tablets or drops, as a standard procedure in caries prevention. This is due to the increasing evidence that the effect of fluoride is mainly the result of chemical reactions on the tooth surface. Therefore, fluoridated toothpastes, gels, varnishes, and rinses are more in focus. Besides this, fluoridated water and fluoridated salt are still important. Although they have a systemic effect, the efficacy of these fluoride applications results from local processes.

Cleaning efficacy and soft tissue trauma after use of manual toothbrushes with different bristle stiffness.

BACKGROUND: The purpose of this study is to evaluate the efficacy of manual toothbrushes of the same type with different bristle stiffness concerning plaque removal, gingivitis development, and soft tissue trauma. METHODS: In a randomized controlled trial, three groups with 40 subjects each used manual toothbrushes with either hard-, medium-, or soft-bristle stiffness. The at-home brushing time was set for 2 minutes, twice a day. Four and 8 weeks after the baseline examination, clinical parameters for plaque removal, gingivitis, and soft tissue damage were recorded again. Recruitment and examinations of the subjects were performed at the Department of Operative and Preventive Dentistry and Endodontics, Heinrich Heine University. A total of 120 volunteers (age range: 18 to 62 years) were recruited and stratified according to sex and age. Primary outcome measures were differences in the Quigley and Hein index (QHI) and papillary bleeding index (PBI) compared to baseline; secondary outcome measures were differences in the modified approximal plaque index (MAPI) and Danser gingival abrasion index. RESULTS: The QHI and MAPI showed lower index scores in subjects who used hard-bristled toothbrushes after 8 weeks (P <0.05 and P <0.001, respectively). In contrast, subjects who used toothbrushes with hard bristles demonstrated more gingival lesions (P <0.01) and higher PBI scores after 4 and 8 weeks (P <0.001) compared to subjects who used soft- or medium-bristled toothbrushes. CONCLUSION: Manual toothbrushes with hard bristles may better remove plaque, but may also cause more soft tissue trauma compared to brushes with softer bristles.

Efficacy of the Cybersonic in comparison with the Braun 3D Excel and a manual toothbrush.

OBJECTIVES: To evaluate the efficacy of two power toothbrushes (Cybersonic and Braun 3D Excel) and one manual brush (Elmex super 29). MATERIAL AND METHODS: After professional toothcleaning 120 subjects were randomly assigned to three groups. Four weeks later, at baseline, the Quigley-Hein plaque index (QHI), the modified approximal plaque index (API), and the papillary bleeding index (PBI) were recorded. Thereafter the subjects used the assigned toothbrushes for 8 weeks. Improvements of the indices after 4 and 8 weeks were calculated as medians. Kruskal-Wallis- and Mann-Whitney U-test served for statistical analysis. RESULTS: All indices showed statistically significant reductions for both power toothbrushes which were superior to the manual brush (4 weeks: Cybersonic: API, 0.21; PBI, 0.25; QHI, 0.23; Braun: API, 0.20; PBI, 0.39; QHI, 0.22; Elmex: API, 0.04; PBI, 0.02; QHI, 0.07; 8 weeks: Cybersonic: API, 0.28; PBI, 0.36; QHI, 0.41; Braun: API, 0.36; PBI, 0.61; QHI, 0.35; Elmex: API, 0.03; PBI, 0.10; QHI, 0.08; p<0.001). The Braun was superior to the Cybersonic with respect to API after 8 weeks (p<0.05) and PBI after 4 and 8 weeks (p<0.01). CONCLUSION: Cybersonic and Braun 3D Excel may be more efficacious than a manual toothbrush in removing plaque and reducing gingivitis.