Influência da oclusão traumática no processo de reparo do periodonto em dentes submetidos à subluxação

A subluxação caracteriza-se pelo dano ao ligamento periodontal (LP) com sangramento e mobilidade anormal do dente; e a presença de edema na região apical do dente pode provocar discreta extrusão. O objetivo desse estudo foi avaliar a influência da oclusão traumática (OT) no processo de reparo do periodonto em dentes submetidos à subluxação, por meio de análises histomorfométricas e imunoistoquímica. Para este estudo, 90 ratos Wistar com 12 semanas de idade; foram distribuídos em três grupos: controle (C), subluxação (S) e subluxação com oclusão traumática (S+OT); nos períodos experimentais de 7 e 21 dias. A subluxação foi induzida pela aplicação de uma força de 900cN no sentido ocluso-gengival na superfície oclusal do 1ºMSD calibrada por um tensiômetro e a OT foi induzida por uma restauração de resina composta na superfície oclusal do primeiro molar superior direito (1°MSD). Para comparação estatística entre os grupos e períodos foi usado o teste de Kruskal-Wallis com Dunn post hoc teste. No período de 7 dias, houve um aumento significativo da espessura do LP (S-34% e S+OT-80%), da substância fundamental amorfa (S-84% e S+OT-148%) e uma redução significativa da área óssea (S-60,8% e S+OT-81,8%) em relação ao grupo controle. Aos 21 dias houve um aumento da espessura do ligamento periodontal significativo no grupo S+OT e na porcentagem de fibras colágenas (S-86%) no grupo S, mas não no grupo S+OT. A porcentagem de substância fundamental amorfa permaneceu proporcionalmente aumentada nos dois grupos experimentais e o perfil nuclear mostrou um aumento significativo no grupo S quando comparada ao período de 7 dias. Nos 2 grupos experimentais também houve um aumento do número de células TRAP positivas tanto no LP (4x) quanto no osso do septo alveolar (16x). O grupo S apresentou um pequeno aumento na porcentagem da área óssea do septo alveolar, enquanto no grupo S+OT houve redução de 52% da área óssea quando comparada ao mesmo grupo no período de 7 dias. A subluxação com ou sem a OT provocou apenas reabsorções radiculares superficiais e a OT foi capaz de prejudicar o reparo das áreas radiculares reabsorvidas após a subluxação no período de 21 dias. Assim conclui-se que a oclusão traumática agravou os danos no ligamento periodontal, no osso alveolar e na superfície radicular gerados após a subluxação, bem como atrasou o processo de reparo dos mesmos.Subluxation is characterised by damage to the periodontal ligament (PDL), accompanied by bleeding and abnormal tooth mobility. The presence of edema in the apical region of the tooth can provoke discrete extrusion. The aim of this study was to assess the influence of traumatic occlusion (TO) on the periodontal repair process in teeth submitted to subluxation, by means of histomorphometrical and immunohistochemical analyses. For this study, 90 Wistar rats aged 12 weeks were divided into three groups: control (C), subluxation (S) and subluxation with traumatic occlusion (S+TO); with experimental periods of 7 and 21 days. Subluxation was induced by applying a 900cN force in the occlusal-gingival sense on the occlusal surface of the 1st SRM calibrated by a tensiometer. TO was induced by a composed resin restoration on the occlusal surface of the first superior right molar (1st SRM). The Kruskal-Wallis with Dunn post-hoc test was used for group and period comparison. At 7 days, there was a significant increase in PDL width (S-34% and S+TO-80%), amorphous fundamental substance (S-84% and S+TO-148%), and a significant reduction of bone surface (S-60.8% and S+TO-81.8%), in comparison to the control group. After 21 days, there was a significant increase in the periodontal ligament width in group S+TO and in the percentage of collagen fibres in group S (86%), but not in group S+TO. The percentage of amorphous fundamental substance remained proportionally increased in the two experimental groups, and the nuclear profile showed a significant increase in group S, compared to the 7 days period. In the two experimental groups an increase in positive TRAP cells was also observed, in the PDL (4x) as well as in the bone area of the alveolar septum (16x). Group S presented a small increase in the alveolar septum's bone area, whereas group S+TO showed a 52% bone area reduction compared to the same group at 7 days. The subluxation with or without TO caused only superficial root resorption. The TO was able to damage the repair processo of reabsorbed root areas after 21 days of subluxation. It can be concluded that traumatic occlusion aggravates post-subluxation damage to the periodontal ligament, the alveolar bone and the radicular surface, and has a delaying effect on the repair process.Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES

Immediate tooth replantation: root canal filling for delayed initiation of endodontic treatment

Abstract The aim of this study is to evaluate the action of paramonochlorophenol associated with Furacin followed by calcium hydroxide (CH) dressing in the control of inflammatory root resorption in cases of immediate tooth replantation with delayed endodontic treatment. A total of 28 incisors of 3 male dogs were extracted and replanted after 15 minutes, and randomly divided into 3 groups: Group I (n = 8) - endodontic treatment was performed before the extraction and replantation; Group II (n = 10) - endodontic treatment was performed 30 days after replantation and the root canal was filled with CH dressing; Group III (n = 10) - endodontic treatment was performed 30 days after replantation and root canals received temporary medication of paramonochlorophenol-Furacin followed by CH dressing. The animals were euthanized 90 days after replantation. The histomorphological events analyzed at the epithelial reattachment site were the intensity and extent of acute and chronic inflammatory processes, periodontal ligament (PDL) organization, the intensity and extent of acute and chronic inflammatory processes in the PDL space, root resorption, bone tissue, and ankylosis. Data were submitted to the Wilcoxon Signed Ranks Test for group comparison (α = 5%). In Groups I, II and III the periodontal ligament was regenerated and most of the resorption areas were repaired by newly formed cementum. The depth and extent of root resorption were significantly higher in Group II than in Group III. The use of paramonochlorophenol-furacin followed by CH dressing was more effective in controlling inflammatory root resorption after immediate tooth replantation

NA PISTA DE PRÁTICAS E PROFESSORES INOVADORES NA EDUCAÇÃO FÍSICA ESCOLAR

http://dx.doi.org/10.5902/010283085718A tradição (ou a Educação Física tradicional) vem demonstrando mais resistência à mudança do que o esperado pelo movimento renovador da década de 1980. Aos poucos as esperanças iniciais de mudanças massivas da prática, deram lugar a uma expectativa mais modesta de fomentar inovações ou mudanças locais. Uma mudança no enfrentamento teórico-metodológico do problema está relacionada ao reconhecimento da importância do professor e de sua formação nesse processo, bem como, da consideração do ambiente concreto da escola, ou seja, o “chão da escola” ou o cotidiano escolar. Assim sendo, o presente artigo constitui-se numa tentativa de identificar e compreender os processos de inovação pedagógica na Educação Física, levados a efeito por professores em contextos específicos. Tem a intenção também, de dar visibilidade a estas experiências na expectativa de potencializar outras.Palavras chave: Educação Física. Inovação. Prática pedagógica

Systematic review of the effects of excessive occlusal mechanical load on the periodontum of rats

Objective: This study aims to systematically evaluate the effects of traumatic occlusion on the periodontal tissue of rats. The set of questions to be answered were–Can traumatic occlusion acting on a healthy and an unhealthy periodontium cause periodontal destruction? Design: The protocols for systematic review were all developed, following the Preferred Reporting Items for Systematic reviews and Meta-Analyses statement and applied to animal research. Reporting of In vivo experiment guidelines for reporting animal research to assess the risk of bias of the studies. Materials and Methods: A literature search was conducted using MEDLINE through PubMed and manual search from the reference lists of main articles related to the theme. Results: This search strategy identified 65 references, of which 33 were considered inappropriate. The full texts of 32 articles were read, 31 of which did not meet the eligibility criteria and were excluded. The final selection included 1 article for which data was extracted for further evaluation. The article included shows a strongest reaction in the periodontium in front of a secondary occlusal trauma as inflammation and apical migration of the junctional epithelium, bone degradation, and decrease in the quantity of collagen fiber. However, primary occlusal trauma also presents these alterations, with the exception of apical migration of the junctional epithelium. Conclusions: Although only one study was included in the systematic review of traumatic occlusion, there is some evidence from experimental studies on animals that shows a coherent picture of the effects of traumatic occlusion on the periodontium. However, new studies are needed to fully answer the questions posed by this systematic review

Orthodontic extrusion as treatment option for crown-root fracture: literature review with systematic criteria

To review the literature searching for a consensus for the choice of orthodontic extrusion as treatment for crown-root fracture. An electronic search was performed in the databases PubMed, Cochrane Central Register of Controlled Trials and Scopus and a manual search of the Journal Dental Traumatology. Forty articles were found in PubMed and 38 in Scopus and after removal of duplicate sample 51 contained articles. Of these, 48 were excluded for not having orthodontic treatment, no follow-up or follow-up less than 6 months, or not report the presence of crown-root fracture. In manual search in Dental Traumatology 20 articles were found, but none of them met the prerequisites established. So, three articles formed the basis of the study. The choice of how to treat orthodontic extrusion of crown-root fracture was effective and stable, without root and periodontal changes. Factors, such as root formation and presence of pulp vitality were decisive for determining the stages of treatment, however, there is no consensus based on scientific evidence about these protocols

The effect of traumatic dental occlusion on the degradation of periodontal bone in rats

Context: A better understanding of the relation between traumatic dental occlusion and periodontal changes is needed. Aims: This study aimed to evaluate the pattern of osteoclastic activity in the periodontal bone in front of the traumatic dental occlusion in rat molars. Patients and Methods: Traumatic dental occlusion (TO) was induced in twenty rats, which were sacrificed after periods of 2, 5, 7, and 14 days. Transversal histological sections of both jaws were stained with tartrate-resistant acid phosphatase and hematoxylin and eosin. Mann–Whitney U-test was used for group comparison, and Pearson's correlation test was applied for the number of osteoclasts and bone area (BA). Results: Traumatic dental occlusion caused an increase in the number of osteoclasts in the bone of the upper and lower right first molar from days 2–5 to 2–14, respectively. In the TO groups, the number of osteoclasts on the lamina dura and in the center of the alveolar bone septum, respectively, increased almost 4-fold and 9-fold in the lower jaw; and 3-fold and 5-fold in the upper jaw, during all periods. In the TO groups, the BA of the alveolar bone septum was substantially reduced. There was a negative correlation between the number of osteoclasts and BA in both jaws during all experimental periods. Conclusions: Traumatic dental occlusion increases osteoclast activity in the alveolar lamina dura and in the center of alveolar bone and stimulates a higher degradation in the center of the alveolar bone septum