Antimicrobial effects of a pulsed electromagnetic field: an in vitro polymicrobial periodontal subgingival biofilm model.

The objective was to test the influence of a pulsed electromagnetic field (PEMF) on bacterial biofilm colonization around implants incorporated with healing abutments. Healing abutments with (test group) and without (control group) active PEMF devices were placed in a multispecies biofilm consisting of 31 different bacterial species. The biofilm composition and total bacterial counts (x105) were analyzed by checkerboard DNA-DNA hybridization. After 96 h, the mean level of 7 out of the 31 bacterial species differed significantly between groups, namely Eubacterium nodatum, Fusobacterium nucleatum ssp. nucleatum, Streptococcus intermedius, Streptococcus anginosus, Streptococcus mutans, Fusobacterium nucleatum ssp. Vicentii and Capnocytophaga ochracea were elevated in the control group (p < 0.05). The mean total bacterial counts were lower in the Test group vs the control group (p < 0.05). An electromagnetic healing cap had antimicrobial effects on the bacterial species and can be used to control bacterial colonization around dental implants. Further clinical studies should be conducted to confirm these findings.

Effect of the Pulsed Electromagnetic Field (PEMF) on Dental Implants Stability: A Randomized Controlled Clinical Trial.

A pulsed electromagnetic field (PEMF) has been shown to contribute to heightening bone regeneration in a range of clinical areas, including dentistry. Due to the scarcity of studies using PEMF in oral implantology, the present experiment scrutinized the effect of PEMF can lead to improving the stability of the implant. A total of 19 subjects (40 implants in total) were selected to participate in the current study and were randomly allocated to either the PEMF group or control group. Subjects in the PEMF group received an activated miniaturized electromagnetic device (MED) while the control group received a sham healing cup. Implants stability was assessed by resonance frequency analyses (RFA) via implant stability quotient (ISQ) calculations. RFA were recorded as following: immediately after procedure, and then 2, 4, 6, 8 and 12 weeks later. Radiographic analysis was performed at baseline, 6 and 12 weeks after implant placement. Proinflammatory cytokines were evaluated in peri-implant crevicular fluid (PICF). The PEMF group presented higher ISQ mean values when compared to the control group. The primary stability time frame (the first 2 weeks) MED group depicted an increase in stability of 6.8%, compared to a decrease of 7.6% in the control group related to the baseline. An overall stability increase of 13% was found in MED treated group (p = 0.02), in contrast, the overall stability in the control group decreased by 2% (p = 0.008). TNF-α concentration during first 4 weeks was lower in the MED treated group. The data strongly suggests that MED generated continuing a PEMF may be considered as a new way to stimulate the stability of the implants at the early healing period.

Miniaturized Electromagnetic Device Abutment Improves Stability of the Dental Implants.

BACKGROUND: The overall success and predictability of dental implant treatment hinge on the primary stability, direct bone-to implant contact formation, and quantity and/or quality of residual bone. Pulsed electromagnetic field has been reported to increase bone regeneration in various clinical situations. Therefore, it was hypothesized that devices which could locally generate a Pulsed electromagnetic field would stimulate bone healing and increase bone density surrounding implants. OBJECTIVE: To retrospectively assess the effects of the miniaturized electromagnetic device (MED) on the implants stability for the first time in human subjects, in a prospective case controlled series. METHODS: Twelve consecutive patients (28 implants) were included in the study.Twelve MED healing caps and 16 regular control healing caps were inserted. Resonance frequency analysis (RFA) was performed at implant placement and abutment connection and an implant stability quotient value was given for each implant. RESULTS: Twenty-eight dental implants were included in the current study. Maxillary implants stability was significantly higher with MED healing cups compared with controls at 15 days postimplantation (66.2 vs 62.1, P = .0008). Resonance frequency analysis test performed at 30 days postimplantation demonstrated significantly increased stability in MED as compared with the control 73.5 ±â€Š3.2 vs 66.7 ±â€Š4.8 in mandibular implants and 74 ±â€Š1.7 vs 65 ±â€Š2.3 in maxillary implants. At the 50 days postimplantation, RFA tests revealed markedly higher stability of the maxillary implants with MED active healing caps compared with nonactive 75.4 ±â€Š5.1 vs 68.5 ±â€Š8.5, respectively. CONCLUSIONS: We conclude that MED-abutment implants demonstrated a superior stability during the early phase of healing as compared with standard implants.

Pulsed electromagnetic fields increase osteogenetic commitment of MSCs via the mTOR pathway in TNF-α mediated inflammatory conditions: an in-vitro study.

Pulsed electromagnetic fields (PEMFs) have been considered a potential treatment modality for fracture healing, however, the mechanism of their action remains unclear. Mammalian target of rapamycin (mTOR) signaling may affect osteoblast proliferation and differentiation. This study aimed to assess the osteogenic differentiation of mesenchymal stem cells (MSCs) under PEMF stimulation and the potential involvement of mTOR signaling pathway in this process. PEMFs were generated by a novel miniaturized electromagnetic device. Potential changes in the expression of mTOR pathway components, including receptors, ligands and nuclear target genes, and their correlation with osteogenic markers and transcription factors were analyzed. Involvement of the mTOR pathway in osteogenesis was also studied in the presence of proinflammatory mediators. PEMF exposure increased cell proliferation and adhesion and the osteogenic commitment of MSCs even in inflammatory conditions. Osteogenic-related genes were over-expressed following PEMF treatment. Our results confirm that PEMFs contribute to activation of the mTOR pathway via upregulation of the proteins AKT, MAPP kinase, and RRAGA, suggesting that activation of the mTOR pathway is required for PEMF-stimulated osteogenic differentiation. Our findings provide insights into how PEMFs influence osteogenic differentiation in normal and inflammatory environments.

A new device for improving dental implants anchorage: a histological and micro-computed tomography study in the rabbit.

OBJECTIVE: In the present study, a new healing cap that could generate a pulsed electromagnetic field (PEMF) around titanium implants to stimulate peri-implant osteogenesis was tested in the rabbit model. MATERIALS AND METHODS: A total of 22 implants were inserted in the proximal tibial metaphysis of 22 rabbits. A healing cap containing the active device was inserted in half of the implants (11 test implants); an "empty" healing cap was inserted in the other ones (11 control implants). The animals were euthanized after 2 and 4 weeks, and the samples were processed for micro-computed tomography and histology. The peri-implant volume was divided into coronal (where the PEMF was the strongest) and apical regions. RESULTS: Most of the effects of the tested device were confined to the coronal region. Two weeks post-implantation, test implants showed a significant 56% higher trabecular bone fraction (BV/TV), associated with enhanced trabecular number (Tb.N, +37%) and connectivity density (Conn.D, +73%) as compared to the control group; at 4 weeks, the PEMF induced a 69% increase in BV/TV and 34% increase of Tb.N. There was no difference in the trabecular thickness (Tb.Th) at either time point. Furthermore, we observed a 48% higher bone-to-implant contact (BIC) in the test implants vs. controls after 2 weeks; this increase tended to remain stable until the fourth week. Mature trabecular and woven bone were observed in direct contact with the implant surface with no gaps or connective tissue at the bone-implant interface. CONCLUSIONS: These results indicate that the PEMF device stimulated early bone formation around dental implants resulting in higher peri-implant BIC and bone mass already after 2 weeks which suggests an acceleration of the osseointegration process by more than three times.

[The relationship between whiplash injury and temporomandibular joint dysfunction].

This article aims to discuss the possible relationship between rapid extension-flexion of the neck-whiplash injury and temporomandibular disorders (TMD). Clinical experience and studies revealed that whiplash injury may cause TMD. The pathophysiology of TMD is described as well as clinical and imaging diagnostic criteria. The treatment modalities for TMD are: physiotherapy, nonsteroidal anti-inflammatory drugs and occlusal splints.

Allergic reactions associated with metal alloys in porcelain-fused-to-metal fixed prosthodontic devices-A systematic review.

OBJECTIVE: To systematically review the allergic reactions associated with metal alloys in porcelain-fused-to-metal (PFM) fixed prosthetic devices. METHOD AND MATERIALS: After reviewing the titles and abstracts of the articles as well as removing duplicates, 22 articles were considered relevant. PubMed, Web of Science, ScienceDirect, and Google Scholar from 1970 to 2012 were evaluated, and randomized studies, review articles, case reports, cross-sectional surveys, and abstracts were included. Conference papers and posters were excluded. RESULTS: Although reported, allergic reactions to metallic alloys in the context of PFM devices are not well documented. Allergic reactions to high noble and noble metal alloy cores of palladium and gold and to base metal alloys nickel and cobalt in the context of PFM fixed partial dentures (FPDs) are reported. Each type of metal is associated with a different rate of allergic reactions, which may be attributed to the extent of corrosion of the alloy, population exposure, and the biologic environment. Because few studies document allergic reactions to metals that comprise PFM crowns and partial dentures, further research in this field is necessary to determine the frequency and type of reactions elicited. CONCLUSION: Though allergic reactions to metal alloys used in dentistry are well documented, only few articles focus on the correlation between FPDs and metal allergies. Thus, this paper surveys case reports of hypersensitivity reactions linked to FPDs and reviews the current literature on allergic reactions to the metallic elements comprising those devices.

The effect of Breezy candy on halitosis: a double-blind, controlled, and randomized study.

Halitosis (bad breath) is a common condition that is socially crippling for vast parts of the population and results from malodorous volatile sulfur compounds, which are by-products of oral bacteria. In this doubled-blind, randomized study, 75 subjects with halitosis were evaluated. The participants were treated with or without abrasive microcapsules (candy) containing zinc gluconate 0.5%, propolis 2%, and a combination of both (zinc 0.25% and propolis 1%). The halitosis was assessed by a Halimeter, a portable instrument that measures the emission of volatile sulfur compounds at different time exposures to the treatments. Breezy candy (which is sugar-free) was found effective in the treatment of halitosis for up to 4 hours. While treatment with regular candy (group 1, traditional candy without abrasive particles) showed reduction in malodor of 10%, Breezy candy showed reduction of up to 60% in malodor (P < .0001). Since this was not a longitudinal study, the total duration of the effect was not assessed. Breezy candy in the abrasive form with zinc additive had the best potential to positively affect malodor when treating patients with halitosis. The combined effect of abrasion by microcapsules with zinc supplement represents a novel and successful approach for the treatment of halitosis.

Rehabilitation of an irradiated mandible after mandibular resection using implant/tooth-supported fixed prosthesis: a clinical report.

Patients undergoing mandibular resection often have facial asymmetry and cosmetic disfigurement, which include a retruded, deviated mandible, motor and sensory deficiencies, and abnormal intermaxillary relationship and occlusion. An implant-supported fixed prosthesis can be an optimal treatment modality. However, there is a problem in creating a repeatable, stable plane of occlusion and maxillomandibular relationship. This report describes the treatment sequence and considerations to rehabilitate a patient undergoing mandibular resection and radiotherapy with an implant-supported fixed prosthesis.

[Water fluoridation and public health].

Fluoridation in Israel was first mooted in 1973 and finally incorporated into law in November 2002 obligating the Ministry of Health to add fluoride to the nation's water supply. Epidemiology studies in the USA have shown that the addition of one part per million of fluoride to the drinking water reduced the caries rate of children's teeth by 50% to 60% with no side effects. Both the WHO in 1994 and the American Surgeon General's report of 2000 declared that fluoridation of drinking water was the safest and most efficient way of preventing dental caries in all age groups and populations. Opposition to fluoridation has arisen from "antifluoridation" groups who object to the "pollution" of drinking water by the addition of chemicals and mass medication in violation of the "Patient's Rights" law and the Basic Law of Human Dignity and Liberty. A higher prevalence of hip fractures in elderly osteoporotic women and osteosarcoma in teenagers has been reported in areas where excess fluoride exists in the drinking water. However, none of the many independent professional committees reviewing the negative aspects of fluoridation have found any scientific evidence associating fluoridation with any ill-effects or health problems. In Israel, where dental treatment is not included in the basket of Health Services, fluoridation is the most efficient and cheapest way of reducing dental disease, especially for the poorer members of the population.

Hereditary gingival fibromatosis with distinct dental, skeletal and developmental abnormalities.

A case of a 9-year-old child with hereditary gingival fibromatosis, supernumerary tooth, chest deformities, auricular cartilage deformation, joint laxity and undescended testes is described. The exact mode of inheritance is unclear; a new mutation pattern is possible. These features resemble but differ from the previously reported Laband syndrome. The dental treatment consisted of surgical removal of the fibrous tissue and conservative restorative treatment under general anesthesia. The dental practitioner should be alert for developmental abnormalities such as supernumerary teeth and delayed tooth eruption. A comprehensive medical history and physical systemic evaluation is essential to rule out other systemic abnormalities. Genetic consultation is mandatory for future family planing.