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Mutans streptococci remained viable on toothbrush bristles, in vivo, for 44 h.

“Background
Toothbrushes harbor a high number of cariogenic microorganisms.

Aim
To investigate the viability of mutans streptococci (MS) on toothbrushes bristles and the production of extracellular polysaccharide (ECP) related to drying time.

Design
Twenty children were submitted to brushing without dentifrice. Toothbrushes were kept at room temperature from 0 to 48 h and then submitted to microbiological processing. The number of MS colonies/biofilms was expressed according to scores: 0 = no colonies were detected; 1 = 1 to 50; 2 = 51 to 100; 3 = over 100. The amount of ECP was evaluated according to scores: 0 = absence; 1 = ECP recovering until 50% of the surface; 2 = ECP recovering more than 50% of the surface. Data were analyzed by Wilcoxon test (α = 5%).

Results
At the periods of 0 to 16 h, the toothbrushes had intense bacterial contamination (score 3). From the 18-h, there was a statistically significant decrease in the MS viability (P = 0.0078), with predominance of score 1 on periods of 20 to 44 h. The most detected ECP amount was at 0- and 12-h period (P < 0.05) with reduction until 32-h period.

Conclusions
Mutans streptococci remained viable on toothbrushes bristles, in vivo, for 44 h.”

A 24-month evaluation of amalgam and resin-based composite restorations: Findings from The National Dental Practice-Based Research Network.

“Results. A total of 226 practitioners followed up 6,218 direct restorations in 3,855 patients; 386 restorations failed (6.2 percent) during the mean (standard deviation) follow-up of 23.7 (8.8) months. The number of tooth surfaces restored at baseline helped predict subsequent restoration failure; restorations with four or more restored surfaces were more than four times more likely to fail. Restorative material was not associated significantly with longevity; neither was tooth type. Older patient age was associated highly with failure (P < .001). The failure rate for children was 4 percent, compared with 10 percent for people 65 years or older. Dentist’s sex and practice workload were associated significantly with restoration longevity.”

Impact of bone harvesting techniques on cell viability and the release of growth factors of autografts.

BACKGROUND:

Autogenous bone grafts obtained by different harvesting techniques behave differently during the process of graft consolidation; the underlying reasons are however not fully understood. One theory is that harvesting techniques have an impact on the number and activity of the transplanted cells which contribute to the process of graft consolidation.

MATERIALS AND METHODS:

To test this assumption, porcine bone grafts were harvested with four different surgical procedures: bone mill, piezosurgery, bone drilling (bone slurry), and bone scraper. After determining cell viability, the release of molecules affecting bone formation and resorption was assessed by reverse transcription polymerase chain reaction and immunoassay. The mitogenic and osteogenic activity of the conditioned media was evaluated in a bioassay with isolated bone cells.

RESULTS:

Cell viability and the release of molecules affecting bone formation were higher in samples harvested by bone mill and bone scraper when compared with samples prepared by bone drilling and piezosurgery. The harvesting procedure also affected gene expression, for example, bone mill and bone scraper samples revealed significantly higher expression of growth factors such as bone morphogenetic protein-2 and vascular endothelial growth factor compared with the two other modalities. Receptor activator of nuclear factor kappa B ligand expression was lowest in bone scraper samples.

CONCLUSION:

These data can provide a scientific basis to better understand the impact of harvesting techniques on the number and activity of transplanted cells, which might contribute to the therapeutic outcome of the augmentation procedure.

The oral microbiome in health and disease.

The human mouth harbours one of the most diverse microbiomes in the human body, including viruses, fungi, protozoa, archaea and bacteria. The bacteria are responsible for the two commonest bacterial diseases of man: dental caries (tooth decay) and the periodontal (gum) diseases. Archaea are restricted to a small number of species of methanogens while around 1000 bacterial species have been found, with representatives from the phyla Actinobacteria, Bacteroidetes, Firmicutes, Proteobacteria, Spirochaetes, Synergistetes and Tenericutes and the uncultured divisions GN02, SR1 and TM7. Around half of oral bacteria are as yet uncultured and culture-independent methods have been successfully used to comprehensively describe the oral bacterial community. The human oral microbiome database (HOMD, www.homd.org) provides a comprehensive resource consisting of descriptions of oral bacterial taxa, a 16S rRNA identification tool and a repository of oral bacterial genome sequences. Individuals’ oral microbiomes are highly specific at the species level, although overall the human oral microbiome shows few geographical differences. Although caries and periodontitis are clearly bacterial diseases, they are not infectious diseases in the classical sense because they result from a complex interaction between the commensal microbiota, host susceptibility and environmental factors such as diet and smoking. Periodontitis, in particular, appears to result from an inappropriate inflammatory reaction to the normal microbiota, exacerbated by the presence of some disease-associated bacterial species. In functional terms, there appears to considerable redundancy among the oral microbiota and a focus on functional rather than phylogenetic diversity may be required in order to fully understand host-microbiome interactions.

By |2019-06-02T01:16:07+00:00January 1st, 2013|Other|

Ex-vivo effect of intracanal medications based on ozone and calcium hydroxide in root canals contaminated with Enterococcus faecalis.

“This ex vivo study evaluated the antibacterial effect of intracanal medications in root canals contaminated with Enterococcus faecalis. Fifty single-rooted human teeth were contaminated with E. faecalis (ATCC 29212) and incubated at 37°C for 21 days. The specimens were randomly divided into 5 groups according to the intracanal medication used: OZ-PG: ozonized propylene glycol; CH/CPMC: calcium hydroxide/camphorated paramonochlorophenol; OZ-PG/CH ozonized PG/CH; PC: positive control group (no medication); and NC: negative control group (no contamination). The samples were collected after 7 days (post-medication) and 14 days (final). Bacterial growth was checked by counting the colony-forming units (CFU). OZ-PG and CH/CPMC reduced significantly the CFU counts compared with PC in the post-medication and final samples, with no statistically significant differences among them. On the other hand, OZ-PG/CH did not reduce significantly the number of bacteria compared with PC. In conclusion, among the evaluated medications OZ-PG and CH/CPMC were the most effective against E. faecalis.”

RANTES and fibroblast growth factor 2 in jawbone cavitations: triggers for systemic disease?

BACKGROUND:

Jawbone cavitations (JC) are hollow dead spaces in jawbones with dying or dead bone marrow. These areas are defined as fatty degenerative osteonecrosis of the jawbone or neuralgia-inducing cavitational osteonecrosis and may produce facial pain. These afflictions have been linked to the immune system and chronic illnesses. Surgical debridement of JC is reported to lead to an improvement in immunological complaints, such as rheumatic, allergic, and other inflammatory diseases (ID). Little is known about the underlying cause/effect relationship.

OBJECTIVES:

JC bone samples were analyzed to assess the expression and quantification of immune modulators that can play a role in the pathogenesis of IDs. The study supports a potential mechanism where JC is a mediating link in IDs.

MATERIALS AND METHODS:

Samples of fatty softened bone taken from JCs were extracted from 31 patients. The specimens were analyzed by bead-based multiplex technology and tested for seven immune messengers.

RESULTS:

Regulated upon activation, normal T-cell expressed, and secreted (RANTES) and fibroblast growth factor (FGF)-2 were found at high levels in the JCs tested. Other cytokines could not be detected at excessive levels.

DISCUSSION:

The study confirms that JC is able to produce inflammatory messengers, primarily RANTES, and, secondarily, FGF-2. Both are implicated in many serious illnesses. The excessive levels of RANTES/FGF-2 in JC patients with amyotrophic lateral sclerosis, multiple sclerosis, rheumatoid arthritis, and breast cancer are compared to levels published in medical journals. Levels detected in JCs are higher than in the serum and cerebrospinal fluid of amyotrophic lateral sclerosis and multiple sclerosis patients and four-fold higher than in breast cancer tissue.

CONCLUSION:

This study suggests that JC might serve as a fundamental cause of IDs, through RANTES/FGF-2 production. Thus, JC and implicated immune messengers represent an integrative aspect of IDs and serve as a possible cause. Removing JCs may be a key to reversing IDs. There is a need to raise awareness about JC throughout medicine and dentistry.

By |2019-11-23T01:02:47+00:00January 1st, 2013|Other|

A case of multiple sclerosis improvement following removal of heavy metal intoxication: lessons learnt from Matteo’s case.

“Multiple sclerosis (MS) is a chronic progressive disease of the central nervous system (CNS) provoking disability and neurological symptoms. The exact causes of SM are unknown, even if it is characterized by focal inflammatory lesions in CNS accompanied by autoimmune reaction against myelin. Indeed, many drugs able to modulate the immune response of patients have been used to treat MS. More recently, toxic metals have been proposed as possible causes of neurodegenerative diseases. The objective of this study is to investigate in vivo the impact of heavy metal intoxication in MS progression. We studied the case of a patient affected by MS, who has been unsuccessfully treated for some years with current therapies. We examined his levels of toxic heavy metals in the urine, following intravenous “challenge” with the chelating agent calcium disodium ethylene diamine tetraacetic acid (EDTA).The patient displayed elevated levels of aluminium, lead and mercury in the urine. Indeed, he was subjected to treatment with EDTA twice a month. Under treatment, the patient revealed in time improved symptoms suggestive of MS remission. The clinical data correlated with the reduction of heavy metal levels in the urine to normal range values. Our case report suggests that levels of toxic metals can be tested in patients affected by neurodegenerative diseases as MS.”

By |2018-04-20T17:54:42+00:00January 1st, 2012|Other|

Twenty-five-year atraumatic restorative treatment (ART) approach: a comprehensive overview.

“BACKGROUND:

The atraumatic restorative treatment (ART) approach was born 25 years ago in Tanzania. It has evolved into an essential caries management concept for improving quality and access to oral care globally.

RESULTS:

Meta-analyses and systematic reviews have indicated that the high effectiveness of ART sealants using high-viscosity glass ionomers in carious lesion development prevention is not different from that of resin fissure sealants. ART using high-viscosity glass ionomer can safely be used to restore single-surface cavities both in primary and in permanent posterior teeth, but its quality in restoring multiple surfaces in primary posterior teeth cavities needs to be improved. Insufficient information is available regarding the quality of ART restorations in multiple surfaces in permanent anterior and posterior teeth. There appears to be no difference in the survival of single-surface high-viscosity glass-ionomer ART restorations and amalgam restorations.

DISCUSSION:

The use of ART results in smaller cavities and in high acceptance of preventive and restorative care by children. Because local anaesthesia is seldom needed and only hand instruments are used, ART is considered to be a promising approach for treating children suffering from early childhood caries. ART has been implemented in the public oral health services of a number of countries, and clearly, proper implementation requires the availability of sufficient stocks of good high-viscosity glass ionomers and sets of ART instruments right from the start. Textbooks including chapters on ART are available, and the concept is being included in graduate courses at dental schools in a number of countries. Recent development and testing of e-learning modules for distance learning has increasingly facilitated the distribution of ART information amongst professionals, thus enabling more people to benefit from ART. However, this development and further research require adequate funding, which is not always easily obtainable. The next major challenge is the continuation of care to the frail elderly, in which ART may play a part.

CONCLUSION:

ART, as part of the Basic Package of Oral Care, is an important cornerstone for the development of global oral health and alleviating inequality in oral care.”

By |2018-04-19T20:33:12+00:00January 1st, 2012|Other|

Systemic affliction of oral focal sepsis.

Multitude of etiologies can cause diseases in various systems. One important etiology is focal sepsis in the oral cavity which has been hypothesized till now to cause various diseases. This hypothesis has now been proved beyond doubt.

By |2019-06-06T23:08:47+00:00January 1st, 2012|Other|

Is the evidence supporting dental procedures strong? A survey of Cochrane systematic reviews in oral health.

“METHOD:

All Cochrane systematic reviews (CSR) published in dentistry were surveyed. The authors’ conclusions about the quality of evidence supporting a specific clinical treatment were used as the measure of outcome. The evidence was considered adequate if the authors did not clearly state the evidence was weak in the conclusions while also suggesting some evidence of the effectiveness of the therapy.

RESULTS:
Of 120 CSRs assessed, in only 26 (22.0% of the reviews) was the quality of evidence regarded as adequate for supporting clinical decisions, although some methodological limitations were identified in the full text of these reviews. Moreover, the authors of most reviews reported weak or unavailable evidence.”

By |2018-04-19T15:34:00+00:00January 1st, 2012|Other|
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