Inhibition of plaque formation and gingivitis in beagle dogs by topical use of a degradable controlled-release system containing chlorhexidine.

The in vivo efficacy of a newly-developed dental application of a film-forming, chlorhexidine-containing system was examined in beagle dogs. A self-disintegrating film-forming solution was applied three times weekly to the dentitions of 7 out of 13 dogs, which were fed a soft-food diet. Plaque accumulation (Plaque Index) and gingival inflammation (Gingival Index) were recorded at one, two, four, six, and eight weeks. The local delivery of low-dose chlorhexidine to dogs significantly inhibited gingivitis and plaque formation. It is concluded that the dental application of a film-forming system may be a preferable method of periodontal disease prophylaxis, and may enhance supragingival plaque control in areas of isolated periodontal problems associated with obvious local predisposing factors.     

Is C-reactive protein level a marker of advanced motor and neuropsychiatric complications in Parkinson’s disease?

C-reactive protein (CRP) is a plasma protein involved in inflammation. While its levels have been associated with stroke, cognitive impairment and depression, the association with clinical characteristics of Parkinson’s disease (PD) is unknown. A total of 73 consecutive patients with PD (46 males, age 68.8 ± 11.5 years) were evaluated regarding motor as well as cognitive and psychiatric features of PD. Plasma CRP levels were determined and tests for associations with disease parameters were performed. The average level of CRP was 3.9 ± 4.1 μmol/L, and 45.2% of the patients (n = 33) had a level above 3.0 μmol/L. Patients in the high CRP group tended to be older (71.4 ± 9.2 vs. 66.7 ± 12.9 years; p = 0.08) and coronary artery disease (CAD) was more common (36 vs. 10%, p < 0.05) in the high CRP group, but no differences were found between the groups regarding gender, disease duration, levodopa dose, motor scores or most of the neuropsychiatric complications such as severity of depression, psychosis, dementia, cognitive decline or frontal lobe dysfunction. Reported depression (at present or in the past) was more common in the high CRP group (54.5 vs. 25%, p = 0.01). CRP levels in patients with PD are associated with a higher prevalence of CAD, but are not associated with PD duration or severity, or with neuropsychiatric complications other than reported depression.     

Long-term bio-degradation of cross-linked and non-cross-linked collagen barriers in human guided bone regeneration

OBJECTIVE: This double-blind study clinically and histologically evaluated long-term barrier bio-durability of cross-linked and non-cross-linked collagen membranes (CLM and NCLM) in sites treated by guided bone regeneration procedures. MATERIALS AND METHODS: In 52 patients, 52 bony defects were randomly assigned to treatment with either a CLM or a NCLM. Post-surgical spontaneous membrane exposures were recorded. Before implant placement, full-thickness standard soft tissue discs were retrieved wherever suitable for histologic examination. RESULTS: Spontaneous membrane exposure was observed in 13 (50%) CLM sites and in six (23.1%) NCLM sites (P<0.05). Clinical healing at exposed sites lasted 2-4 weeks. CLM were histologically intact in all non-perforated sites, were interrupted in five perforated sites, and undetected in four. NCLMs were undetected in all 18 specimens examined. In three non-perforated CLM sites, bone apposition and ossification at or within the membrane was observed. CONCLUSIONS: CLMs were more resistant to tissue degradation than NCLMs, and maintained integrity during the study. Neither membrane was resistant to degradation when exposed to the oral environment. CLMs were associated with a higher incidence of tissue perforations. In non-perforated sites, CLM ossification at or within the membrane was occasionally observed.     

Effect of gender on acute pain prediction and memory in periodontal surgery

Pain is a complex experience that is affected by factors such as gender, stress, anxiety and cognitions. The purpose of this study was to investigate the inter-relationship between gender and acute pain prediction and memory under periodontal surgery treatment. The study was conducted on 15 male and 22 female dental patients (mean age 34 yr, mean education level 14.7 yr), who were scheduled for periodontal surgery. Patients were evaluated during four consecutive appointments: at initial check-up, immediately pre-operatively, 1 wk post-operatively, and at 4 wk post-operative follow-up. Patients were requested to complete questionnaires concerning their anxiety at each appointment and to indicate their subjective evaluations concerning pain (on a visual analogue scale). Evaluations concerning expectation to experience pain during the planned surgery (pain prediction) were made at the first two appointments and evaluations of the experienced pain as remembered from the surgery (pain memory) were made at the last two appointments. Gender had a significant effect on pain prediction and pain memory. Men expected to experience more pain pre-operatively than women but remembered less pain post-operatively. It was concluded that cognitive pain perception in clinical situations differs between genders.     

Scanning electron microscope evaluation of wear of stainless steel and high carbon steel curettes

Root planing depends on quality instrument cutting edges. The sharpness and wear of stainless steel (SS) and high carbon steel (HCS) dental curettes were compared before and after standardized root planing procedures. Forty working edges of dental curettes, 20 of each alloy, were examined by scanning electron microscope (SEM) prior to any root planing (control), after 15 strokes, and after 45 strokes. Root planing was carried out on freshly extracted, single-rooted teeth, mounted in natural positions in mannikin jaws. Working areas measuring 3 x 5 mm were marked on root surfaces previously exposed by periodontitis. Each working edge was examined at points 1 mm and 2 mm from the tip under the same magnification (x 240). Microscopic observations showed that edge deformation increased from the control (factory sharpened) group, to the "15 stroke" group, and from the "15" to the "45 stroke" group, in both SS and HCS curettes. SS curettes, however, demonstrated significantly more wear than HCS curettes. After 45 strokes, only 5% of the SS curettes were sharp, compared to 20% of the HCS curettes. While 65% of the SS curettes showed severe edge deformation by the end of the study, only 20% of the HCS curettes were severely deformed (P less than 0.01). The results indicate that HCS curettes are more resistant to wear than SS curettes. Further study is indicated to evaluate the relationship between actual bevel dimensions and root planing effectiveness.     

Mental health status among younger generation around Chernobyl

Introduction

In order to improve our understanding of how to approach the younger generation around Chernobyl, we screened mental health status among young adults born after the accident living in the Gomel region, Belarus.

Material and methods

We enrolled 697 medical students who were born after the accident. Participants were asked to answer self-administered questionnaires including the General Health Questionnaire (GHQ-12).

Results

GHQ-12 scores were 1.80 ±2.28 (mean ± SD) among all 697 subjects. When logistic regression analysis was performed with confounding factors, “economic situation” and “association of diseases and/or poor health condition with radiation exposure” were significantly associated with poor mental status.

Conclusions

Our findings suggest that anxiety about radiation exposure among highly educated medical students in the Gomel region, although they were born after the accident, affects their poor mental health status.     

Spatial distribution of abnormal EEG activity in Creutzfeldt-Jakob disease

ObjectivesElectroencephalogram (EEG) pattern in Creutzfeldt-Jakob disease (CJD) is characterized by diffuse abnormal activity, although lateralization to one hemisphere has been described in the first stages of the disease. This study aimed to determine whether abnormal EEG activity predominantly occurs in anterior versus posterior brain regions.MethodsAs part of a prospective study, the demographics, clinical features and MRI findings of genetic E200K CJD patients were collected. EEG was performed and the recordings reviewed for the typical periodic sharp wave complex (PSWC) and non-specific slow activity. Data were analyzed using the qEEG tool, and the activity in anterior and posterior regions of the brain compared.ResultsEleven genetic E200K CJD patients were included in the study (67% women). The average age was 59.1 ± 8.4 SD years and the average disease duration was 2.4 ± 2.1 months. EEG showed the classic PSWC pattern in 5/11 (45%) of the patients, and slow activity was seen in 9/11 (82%). EEG was normal in 2 patients. PSWC activity was diffuse in 2/5 patients and unilateral in 3/5 patients; slow activity was diffuse in 9 patients. Quantitative analysis of PSWC and slow activity showed no significant difference between anterior and posterior distribution.ConclusionThe abnormal EEG activity in CJD is diffuse with no clear spatial predominance in anterior or posterior brain regions.