40 research outputs found
Impact of micronutrients supplementation on bone repair around implants: microCT and counter-torque analysis in rats
ABSTRACT The use of natural substances and micronutritional approaches has been suggested as a therapeutic alternative to benefit the bone healing associated with no side effects. Nevertheless, the influence of micronutritional interventions with therapeutic proprieties on the bone repair has yet to be intensely evaluated, and no evidence is available exploring the impact of micronutrient supplementation on the peri-implant bone healing. Objective This study investigated the effect of micronutrients supplementation on the bone repair around implants. Material and Methods One screw-shaped titanium implant was inserted in each tibia of each rat, which were assigned to: daily administration, for 30 d, of the placebo solution (Placebo group-n:18) or micronutrients supplementation (Micronutrients group-n:18), based on calcium, magnesium, zinc, and vitamin D3 intake. After, the animals were sacrificed. One of the implants was removed by applying a counter-torque force to evaluate the force to rupture the bone-implant interface. The other implant was evaluated by microcomputed tomography (CT) examination to determine the bone-to-implant contact (BIC) and the bone volume (BV/TV). Results No statistically significant differences were observed between the groups for both counter-torque values and microCT parameters (p>;0.05). Conclusion Within the limits of this study, micronutrients supplementation did not provide additional benefits to the bone healing around dental implants
Maternal periodontitis induces intergenerational injuries on reproductive performance of adult female rat offspring
Substantial evidence suggests a direct link between periodontitis in pregnant women and subsequent adverse pregnancy outcomes. However, no studies have evaluated the transgenerational effects of periodontitis on the reproductive performance of subsequent generations. The present study investigated whether maternal periodontal disease exerts deleterious transgenerational effects on reproductive performance in F1 female rats. Rat female offspring from mothers that were subjected to experimentally induced periodontitis or sham operation were mated with sexually experienced male rats. The weight and reproductive performance of these F1 offspring were evaluated on gestation day 21, including maternal weight, litter weight, individual pup weight, number of pups, and number of resorptions. The percentage of dams with resorptions and the litter weight/number of pups were also calculated. Compared with the control group, an increase was observed in the percentage and number of resorptions and litter weight/number of pups, and a decrease was observed in the number of pups born in the experimental group. Maternal weight, litter weight, and individual pup weight were not different between the control and experimental groups. Maternal periodontitis impaired reproductive performance in the F1 generation. We showed that periodontitis may induce reproductive injury in adult offspring even if the offspring do not undergo any inflammatory/infectious process during their postnatal life or during gestation. These findings reinforce the importance of oral care during pregnancy. Existem evidências substanciais de uma relação direta entre periodontite em mulheres grávidas com efeitos adversos reprodutivos. No entanto, nenhum estudo avaliou os efeitos intergeracionais da periodontite sobre o desempenho reprodutivo das gerações subsequentes. O presente estudo investigou se a doença periodontal materna exerce efeitos intergeracionais deletérios sobre o desempenho reprodutivo em ratos fêmeas da geração F1. Assim, filhas de ratas cujas mães foram submetidas a periodontite experimental ou falsamente operadas foram acasaladas com ratos machos sexualmente experientes. O peso corporal e desempenho reprodutivo da geração F1 foram avaliados no dia 21 de gestação, incluindo o peso materno, peso da ninhada, peso da individual dos filhotes, número de filhotes e de reabsorções. A percentagem de fêmeas com reabsorção e o peso da ninhada/número de filhotes também foram calculados. Comparados com o grupo controle, observou-se aumento na porcentagem e número de reabsorções e no peso da ninhada/ número de filhotes, e decréscimo no número de filhotes nascidos no grupo experimental. O peso materno, peso da ninhada e individual dos filhotes não foi diferente entre o controle e experimental. Estes resultados mostram que a periodontite experimental materna prejudica o desempenho reprodutivo da geração F1, mesmo que estes animais não tenham sido expostos diretamente a um processo inflamatório
Células mesenquimais indiferenciadas em periodontia : novas perspectivas
A engenharia de tecidos é um campo contemporâneo da ciência, que visa criar condições baseadas em princÃpios de biologia celular e molecular, bioengenharia e biomateriais para regenerar tecidos. As células tronco mesenquimais apresentam altas taxas de proliferação e são capazes de se diferenciar, sob certas condições, em multi-linhagens, sugerindo que elas têm grande potencial para atuar no campo da regeneração. As células tronco derivadas de tecidos dentais são uma fonte alternativa adequada de células mesenquimais uma vez que são de fácil acesso e têm baixa morbidade para o doador. Estudos demonstraram que elas já foram isoladas e caracterizadas a partir de diversos tecidos tais como polpa dentária, dentes decÃduos esfoliados, ligamento periodontal, gengiva, folÃculo dental e papila apical. Entretanto, os estudos demonstram que há heterogeneidade entre essas populações e não existe um método padrão para selecionar as células-tronco dentais mais apropriadas para procedimentos regenerativos. O objetivo desta revisão é apresentar o conhecimento atual dos vários tipos de células-tronco derivadas de dentes e discutir as novas perspectivas para seu uso na engenharia de tecidos periodontais.Tissue engineering is a contemporary field of science, which aims to create conditions based on principles of cell and molecular biology, bioengineering and biomaterials to regenerate tissues. Mesenchymal stem cells present high proliferation rates and are able to differentiate into multilineages under certain conditions, suggesting that they have great potential to act in regeneration field. Tooth derived stem cells are a suitable alternative source of mesenchymal cells once they are easily accessible and have poor morbidity to the donor. Studies showed that they have been isolated and characterized from diverse tissues such as dental pulp, exfoliated deciduous teeth, periodontal ligament, gingiva, dental follicle and apical papilla. However studies show that there is heterogeneity among these populations and there is no standard method to select the most appropriate tooth derived stem cells for regenerative procedures. The aim of this review is to present the current perspective of the multiple types of tooth-derived stem cells and to discuss the basis for their use in periodontal tissue engineering
Maternal periodontitis induces intergenerational injuries on reproductive performance of adult female rat offspring
Regenerative approaches in the treatment of furcation lesions are predictable in class ii maxillary facial or interproximal and mandibular facial or lingual class ii furcation defects
This study comprises a systematic review of studies evaluating the effect ofvarious well-recognized regenerative techniques for the managementof furcation lesions in specific clinical scenarios compared with non-regenerative surgical therapy. The following clinical scenarios were evalu-ated: (1) maxillary molars with facial/interproximal Class I furcationdefects; (2) mandibular molars with facial/lingual Class I furcation defects;(3) maxillary molars with facial/interproximal Class II furcation defects;(4) mandibular molars with facial/lingual Class II furcation defects; (5)maxillary molars with Class III furcation defects; (6) mandibular molarswith Class III furcation defects; and (7) maxillary premolars with Class I,II, or III furcation defects. Two investigators reviewed four databases (MEDLINE/PubMed, Scopus, Web of Knowledge, and the Cochrane CentralRegister of Controlled Trials) for human studies published in English,matching specific inclusion criteria (see below inKey Study Factorsection).Initially 1500 entries were identified. The total number of articles selectedafter reviewing the titles and abstracts was 183, of which 150 were eligibleafter full-text review. A total of 24 clinical trials and 13 case series did notreport clearly the clinical scenarios for the furcation defects. A total of113 manuscripts were included in the systematic review (6 systematicreviews, 85 clinical trials, 14 case series, and 8 case reports)15310510
Regenerative Approaches In The Treatment Of Furcation Lesions Are Predictable In Class Ii Maxillary Facial Or Interproximal And Mandibular Facial Or Lingual Class Ii Furcation Defects.
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Effect Of An Estrogen-deficient State And Its Therapy On Bone Loss Resulting From An Experimental Periodontitis In Rats.
The aim of this study was to evaluate the impact of an estrogen-deficient state and its therapies (estrogen and calcitonin administration) upon bone loss resulting from an experimental periodontitis. Fifty-eight Wistar rats were divided into four groups: group 1 (n = 15): sham operated; group 2 (n = 15): ovariectomized; group 3 (n = 14): ovariectomized plus calcitonin administration; group 4 (n = 14): ovariectomized plus estrogen administration. Twenty-one days after ovariectomy or sham surgeries, the ligature was randomly placed. Sixty days later, the animals were killed and the specimens routinely processed. In addition, serum levels of alkaline phosphatase and calcium were assessed. Intergroup analysis revealed that an estrogen-deficient state significantly increased bone loss resulting from periodontitis and that such an effect could not be prevented either by estrogen or calcitonin administration (0.34 +/- 0.13, 0.65 +/- 0.06, 0.63 +/- 0.19, 0.67 +/- 0.28 for groups 1, 2, 3 and 4, respectively). Furthermore, an estrogen-deficient state presented a direct effect on the alveolar bone regardless of plaque accumulation and this effect may be significantly reduced by estrogen administration (p < 0.05). Serum analysis demonstrated a higher bone turnover for the animals with estrogen deficiency, and estrogen therapy restored bone metabolism. Estrogen administration may prevent the direct effect of an estrogen-deficient state on alveolar bone; however, neither estrogen nor calcitonin administration could prevent this effect when associated with a response to a plaque-related inflammatory process.39107-1
Original research Periodontics, Microbiology Fabiano Ribeiro CIRANO (a) Effect of Resveratrol on periodontal pathogens during experimental periodontitis in rats
Abstract: The objective of this study was to investigate the antibacterial effect of resveratrol against putative periodontal pathogens during the progression of experimental periodontitis in rats. Periodontitis was induced in rats in one of the first molars chosen to receive a ligature. Animals were assigned to one of two groups: daily administration of the placebo solution (control group, n = 12) or 10 mg/Kg of resveratrol (RESV group, n = 12). The therapies were administered systemically for 30 days, for 19 days before periodontitis induction and then for another 11 days. Then, the presence and concentrations of Porphyromonas gingivalis, Tannerella forsythia and Aggregatibacter actinomycetemcomitans in the cotton ligatures collected from the first molars were evaluated using real-time PCR. Inter-group comparisons of the microbiological outcomes revealed that no differences were detected for P. gingivalis, T. forsythia and A. actinomycetemcomitans levels (p > 0.05). Continuous use of resveratrol did not promote additional benefits in microbiological outcomes during experimental periodontitis in rats
Histologic evaluation of the effect of nicotine administration on bone regeneration: a study in dogs
The objective of this study was to investigate the histometric impact of nicotine on bone regeneration of surgically created alveolar ridge defects in dogs. Sixteen mongrel dogs were used. One defect was surgically created unilaterally in the mandible, and left to heal spontaneously. The animals were randomly assigned to one of the following groups: Group 1 - control (n = 8) and Group 2 - subcutaneous nicotine administration (2 mg/kg) twice a day (n = 8). After 4 months, the animals were sacrificed and the specimens routinely processed for semi-serial decalcified sections. Bone height (BH), bone width (BW), bone density (BD), and bone area (BA) of the newly-formed bone were evaluated. Intergroup analysis (Mann-Whitney rank sum test) showed that regardless of the presence of nicotine, no significant differences were observed regarding bone width (BW), bone area (BA) and bone height (BH) (p > 0.05). On the other hand, it was demonstrated that nicotine administration significantly influenced the proportion of mineralized tissue within the limits of the newly-formed bone (BD) (p < 0.001). Within the limits of the present study, it can be concluded that nicotine might affect but not prevent bone healing in defects left to heal spontaneously