The effect of acute treadmill walking on cognitive control and academic achievement in preadolescent children.

The effect of an acute bout of moderate treadmill walking on behavioral and neuroelectric indexes of the cognitive control of attention and applied aspects of cognition involved in school-based academic performance were assessed. A within-subjects design included 20 preadolescent participants (age=9.5+/-0.5 years; eight female) to assess exercise-induced changes in performance during a modified flanker task and the Wide Range Achievement Test 3. The resting session consisted of cognitive testing followed by a cardiorespiratory fitness assessment to determine aerobic fitness. The exercise session consisted of 20 min of walking on a motor-driven treadmill at 60% of estimated maximum heart rate followed by cognitive testing once heart rate returned to within 10% of pre-exercise levels. Results indicated an improvement in response accuracy, larger P3 amplitude, and better performance on the academic achievement test following aerobic exercise relative to the resting session. Collectively, these findings indicate that single, acute bouts of moderately-intense aerobic exercise (i.e. walking) may improve the cognitive control of attention in preadolescent children, and further support the use of moderate acute exercise as a contributing factor for increasing attention and academic performance. These data suggest that single bouts of exercise affect specific underlying processes that support cognitive health and may be necessary for effective functioning across the lifespan.

Regional brain activation as a biological marker of affective responsivity to acute exercise: influence of fitness.

Previous research has shown that regional brain activation, assessed via frontal electroencephalographic (EEG) asymmetry, predicts affective responsivity to aerobic exercise. To replicate and extend this work, in the present study we examined whether resting brain activation was associated with affective responses to an acute bout of aerobic exercise and the extent to which aerobic fitness mediated this relationship. Participants (high-fit, n = 22; low/moderate-fit, n = 45) ran on a treadmill for 30 min at 75% VO2max. EEG and affect were assessed pre- and 0-, 10-, 20-, and 30-min postexercise. Resting EEG asymmetry predicted positive affect (as measured by the energetic arousal subscale of the Activation Deactivation Adjective Check List) postexercise. Furthermore, resting frontal EEG asymmetry predicted affect only in the high-fit group, suggesting the effect might be mediated by some factor related to fitness. It was also shown that subjects with relatively greater left frontal activation had significantly more energy (i.e., activated pleasant affect) following exercise than subjects with relatively greater right frontal activation. In conclusion, aerobic fitness influenced the relationship between resting frontal asymmetry and exercise-related affective responsivity.

Walking in (affective) circles: can short walks enhance affect?

Recent physical activity recommendations call for activities that are of moderate intensity and can be performed intermittently during the day, such as walking. These proclamations were based partly on the assumption that moderate activities are generally more enjoyable than physically demanding ones, and they are, therefore, also more likely to be continued over the long haul. However, little is actually known about the affective outcomes of short bouts of walking and extant findings are equivocal. Four experimental studies examined the affective responses associated with short (10- to 15-min) bouts of walking using a dimensional conceptual model of affect, namely, the circumplex. Results consistently showed that walking was associated with shifts toward increased activation and more positive affective valence. Recovery from walking for 10-15 min was associated with a return toward calmness and relaxation. This pattern, was robust across different self-report measures of the circumplex affective dimensions, across ecological settings (field and laboratory), across time, and across samples.

Comparison of bioactive glass to demineralized freeze-dried bone allograft in the treatment of intrabony defects around implants in the canine mandible.

BACKGROUND: The purpose of this study was to evaluate and compare the healing of different bone grafting materials adjacent to titanium plasma-sprayed (TPS) endosseous dental implants. METHODS: Implant osteotomy sites were prepared and standardized 3-walled intrabony defects (3 mm x 5 mm x 5 mm) were created at the mesial of each implant site. Thirty-two TPS implants were placed in edentulous mandibular ridges of the 4 dogs. Periodontal dressings were placed in the defect sites so as to create a defect simulating bone loss around an implant. After 3 months, the periodontal dressing was removed, the defect sites debrided and evaluated for size, and intramarrow penetration performed. The graft materials tested were 1) canine demineralized freeze-dried bone allograft (cDFDBA); 2) bioactive glass granules of a broad size range 90 to 710 microns (BRG); and 3) bioactive glass granules of narrow size range 300 to 355 microns (NRG). One site on each side of the mandible was not filled and served as a control. Dogs were sacrificed 4 months after graft placement. RESULTS: Histologically, differences in percent bone-to-implant contact in the defect area were observed between the treatment groups. cDFDBA>control=BRG=NRG with statistical significance found between cDFDBA and control (P = 0.0379), but no statistically significant difference between control or either bioactive glass material. When comparing percent bone height fill of the defect in the grafted area, cDFDBA (65.7%) was significantly better than the control (48.9%; P < or = 0.05) with no statistically significant difference between control, broad range bioactive glass (57.3%) and narrow range bioactive glass (56.6%). When total bone area was measured, the percentage of new bone in the grafted area was cDFDBA (42.1%), broad range glass (33.1%) and narrow range glass (22.6%) with significance found between cDFDBA and NRG (P = 0.0102). The content of residual graft particles in soft tissue was significant (P = 0.0304) between cDFDBA (1.4%) and NRG (11.4%) with no significant difference between graft material for residual particle content in bone tissue. CONCLUSIONS: The results of this study indicate that percent bone-to-implant contact and percent bone height fill in an intrabony defect around titanium plasma-sprayed implants are statistically significantly higher with the use of DFDBA when compared to bioactive glass material.

A multipurpose template for implant placement.

A case report is presented describing the laboratory fabrication and clinical use of an innovative template. This template was designed to function as a radiographic implant positioning guide, accurate bone sounding guide, and surgical guide. This appliance is intended to serve additional roles as an aid in flap reflection and as a pick-up impression tray.

Prevention and treatment considerations in patients with drug-induced gingival enlargement.

Drug-induced gingival overgrowth is an iatrogenic disease caused by the use of phenytoin, cyclosporine, nifedipine, and other medications in the susceptible patient. The gingival overgrowth can be due to three causes: noninflammatory, hyperplastic reaction to the medication; chronic inflammatory hyperplasia; or a combined enlargement due to chronic inflammation and drug-induced hyperplasia. Drug-induced gingival enlargement can be minimized, but not prevented, by elimination of local irritants, meticulous oral hygiene, and regular periodontal recall. If gingival enlargement interferes with function, speech, esthetics, or oral hygiene, tissue reduction can be accomplished by gingivectomy or a flap procedure. Gingival enlargement may recur, especially in the patient with poor oral hygiene.

Antigenic diversity in the periodontopathogen, Actinobacillus actinomycetemcomitans.

We have identified a significant level of variation in antibody responses to Actinobacillus actinomycetemcomitans outer membrane antigens (OMA). This study was designed to verify A. actinomycetemcomitans antigenic diversity that could contribute to maintaining this chronic infection despite the host immune response. A. actinomycetemcomitans strains (5 from different patients and 3 the same patient) were cultured and OMA prepared for Western immunoblotting studies. Antigen bands in the OMA were identified using 7 sera obtained from 3 adult periodontitis (AP) and 4 localized juvenile periodontitis (LJP) patients that were documented with elevated A. actinomycetemcomitans antibody and infection. Differences/similarities in the antigen patterns among the A. actinomycetemcomitans strains were assessed using a kappa similarity coefficient. Antigen bands in the A. actinomycetemcomitans strains ranged from 11-150 kDa; however, variation in antigen patterns were noted among the strains. Utilizing the human sera as probes for antigenic diversity, the 5 heterologous strains showed average K=0.23 (p < 0.05), while homologous A. actinomycetemcomitans strains had a K=0.48 (p < 0.02). The A. actinomycetemcomitans OMA were used as probes to describe variability in host antibody and as such presumptive evidence of antigenic diversity in A. actinomycetemcomitans that is colonizing each of the patients. The results showed average K=0.26 (p < 0.05) for the patients when tested against each of the heterologous strains, and K=0.14 when tested against the homologous strains (p > 0.1). Finally, antigen bands of M r 80, 65, 58, 31 and 20 kDa were demonstrated as antigens contributing to the antigenic diversity in A. actinomycetemcomitans.