Estudo experimental de implantes com superfície ativada pela tetraciclina: caracterização topográfica, histométrica, histoquímica e imunohistoquímica / Experimental study of implants with surface activated by tetracycline: topographic, histometric, histochemical and immunohistochemical characteristics

Modificações topográficas e físico-químicas da superfície dos implantes têm sido propostas para aumentar a porcentagem de contato osso-implante, principalmente em áreas de tecido ósseo de menor densidade, favorecer as respostas biológicas em um período de reparo mais curto e, consequentemente, favorecer o sucesso a longo prazo dos implantes osseointegráveis. O objetivo deste trabalho foi avaliar experimentalmente a modificação de superfície de implantes dentários pela adição de tetraciclina com avaliações pela Microscopia Eletrônica de Varredura (MEV), Energia Dispersiva de Raios X (EDS), medidas do ângulo de contato e processo de reparo peri-implantar pelo método imunohistomorfometrico. Foram utilizados quarenta e oito implantes (1,6mm de diâmetro e 4,0 mm de comprimento) e 6 discos de titânio (6mm de diâmetro e 1,5 mm de espessura) divididos em dois grupos: Grupo Tratamento Ácido (GA) e Grupo Tratamento Tetraciclina (GT). Para análise topográfica utilizou seis implantes com distribuição igual entre os grupos. Para a análise de rugosidade utilizou-se os 6 discos de titânio com distribuição igual entre os grupos. Para os testes em animais foram utilizados 42 implantes e 42 ratos Wistar igualmente divididos em dois grupos com implantes instalados na tíbia e divididos em três períodos experimentais: 7,30 e 60 dias. Os espécimes foram processados para avaliação histológica e imunoistoquímica. Resultados: A topografia de superfície revelou que GA apresentava microcavidades de rugosidade homogênea, sem contaminação da superfície e com picos de titânio e oxigênio. GT apresentou superfície mais homogênea e regular quando comparado GA, também revelou picos de titânio e oxigênio predominantemente, com presença de discretos picos correspondentes aos elementos cálcio (Ca), fósforo (P), Carbono (C) e Magnésio. GA não apresentou molhamento enquanto GT apresentou um molhamento parcial. Comparando os valores das porcentagens da extensão de tecido ósseo em contato com a superfície do implante (BIC) e a área ocupada por tecido ósseo nas três primeiras roscas do implante (BAFO) apenas em 30 dias apresentou diferença estatística significativa (p< 0,05). Os resultados imunohistomorfométricos apontam para a elevada sequência dinâmica dos processos biológicos de reparo nos primeiros 30 dias após a inserção do implante em ambos os grupos, tendendo ao equilíbrio aos 60 dias. Conclusão A superfície ativada pela tetraciclina se mostrou biocompatível, com ausência de reações inflamatórias junto ao tecido peri-implantar e uma ossificação adequada, sendo qualitativamente e quantitativamente superior ao grupo controle, sugerindo uma osseointegração precoce(AU)

Topographic and physical-chemical modifications of the surface of the implants have been proposed to increase the percentage of bone-implant contact, especially in areas of lower density bone tissue, favor biological responses in a shorter repair period and, consequently, favor the long-term success of osseointegrated implants. The objective of this work was to experimentally evaluate the surface modification of dental implants by adding tetracycline with evaluations by Scanning Electron Microscopy (SEM), X-ray Dispersive Energy (EDS), contact angle measurements and peri-implant repair process by the immunohistomorphometric method. Forty-eight implants (1.6 mm in diameter and 4.0 mm in length) and 6 titanium discs (6 mm in diameter and 1.5 mm in thickness) were used, divided into two groups: Acid Treatment Group (GA) and Group Tetracycline treatment (GT). For topographic analysis, six implants were used with equal distribution between groups. For the roughness analysis, the 6 titanium discs were used with equal distribution between the groups. For the animal tests, 42 implants and 42 Wistar rats were equally divided into two groups with implants installed in the tibia and divided into three experimental periods: 7, 30 and 60 days. The specimens were processed for histological and immunohistochemical evaluation. Results: The surface topography revealed that GA had homogeneous roughness microcavities, without surface contamination and with titanium and oxygen peaks. GT showed a more homogeneous and regular surface when compared to GA, it also revealed titanium and oxygen peaks predominantly, with the presence of discrete peaks corresponding to the elements calcium (Ca), phosphorus (P), carbon (C) and magnesium. GA showed no wetting while GT showed partial wetting. Comparing the values of the percentages of bone tissue extension in contact with the implant surface (BIC) and the area occupied by bone tissue in the first three implant threads (BAFO) in only 30 days, there was a statistically significant difference (p < 0.05). The immunohistomorphometric results point to the high dynamic sequence of biological repair processes in the first 30 days after insertion of the implant in both groups, tending to balance at 60 days. Conclusion The surface activated by tetracycline proved to be biocompatible, with no inflammatory reactions close to the peri-implant tissue and adequate ossification, being qualitatively and quantitatively superior to the control group, suggesting early osseointegration(AU)

Avaliação do hidróxido de cálcio associado à própole com agitação ultrassônica como curativo intracanal em reimplante dentário tardio / Evaluation of calcium hydroxide mixed with propolis by ultrasonic activation as root canal dressing in delayed tooth replantation

Na avulsão dentária ocorre o rompimento do feixe vásculo-nervoso que nutre a polpa e, após o reimplante tardio, existe a necessidade do tratamento endodôntico. A pasta de hidróxido de cálcio (Ca (OH)2) é a medicação intracanal mais empregada em razão de suas excelentes propriedades biológicas, porém várias substâncias têm sido associadas a este na tentativa de melhorar a sua ação antimicrobiana. O objetivo do estudo foi avaliar o efeito do uso de curativo intracanal de hidróxido de cálcio (Ca (OH)2) associado à própole a 10% seguida da agitação ultrassônica em reimplante tardio de dentes de rato. Vinte e quatro ratos tiveram o incisivo superior direito extraído e deixado em bancada por uma hora. Em seguida, foram removidos: papila dentária, polpa dentária e ligamento periodontal. Os dentes foram imersos em solução de fluoreto de sódio fosfato acidulado a 2%. Na sequencia os canais radiculares foram secos e os animais divididos em quatro grupos experimentais: Grupo Ca (OH)2, Grupo Ca (OH)2 seguido da agitação ultrassônica, Grupo Ca(OH)2 e própole, Grupo Ca(OH)2 e própole seguido da agitação ultrassônica. Após a colocação do curativo, foi confeccionado um plug apical de MTA. Os alvéolos foram irrigados com soro fisiológico e os dentes reimplantados. Decorridos 60 dias do reimplante, os animais sofreram eutanásia. Quanto ao infiltrado inflamatório agudo no ligamento periodontal, houve diferença estatisticamente significante entre os grupos Ca(OH)2 e Ca(OH)2 e própole. Com relação ao infiltrado inflamatório crônico no ligamento periodontal, houve diferença significante entre os grupos Ca(OH)2 seguido da agitação ultrassônica e Ca(OH)2 e própole. A reabsorção radicular estava presente em todos os grupos sem diferença estatística. Conclui-se que o uso do curativo intracanal de hidróxido de cálcio associado à própole a 10% seguido da agitação ultrassônica não se mostrou mais efetivo que o Ca(OH)2 no processo de reparo do reimplante tardio de dentes de rato

In tooth avulsion it is the disruption of the neurovascular bundle that nourishes the flesh, and after delayed replantation there is a need for endodontic treatment. Calcium hydroxide (Ca(OH)2) is the most commonly used substance to delay healing, due to its excellent biological properties. However, many substances have been associated with it in an attempt to improve their antimicrobial activity. The aim of this study was to evaluate the effect of intracanal dressing of calcium hydroxide associated with propolis 10% followed by ultrasonic agitation. in delayed replantation of rat teeth. Twenty four rats had the right upper incisor extracted, which was left on the bench-dried for an hour. It was then removed from the dental papilla, and pulp, the periodontal ligament and teeth were immersed in sodium fluoride solution at 2% acidulated phosphate. After this procedure, the root canals were dried with paper cones and the were animals divided into four groups according to the employed intracanal dressing: Group Ca(OH)2, Group Ca(OH)2 with ultrasonic agitation, Group Ca(OH)2 and propolis, Group Ca(OH)2 and propolis with ultrasonic agitation. After placing the bandage, an apical plug of MTA will be made. The root canals were irrigated with saline and the teeth were replanted. Sixty days after replantation, the animals were euthanised. As for the acute inflammatory infiltrate in the periodontal ligament, there was no statistically significant difference between groups Ca(OH)2 and Ca(OH)2 and propolis. Regarding the chronic inflammatory infiltrate in the periodontal ligament, there was no significant difference between group Ca(OH)2 with ultrasonic agitation and the group Ca(OH)2 and propolis. Root resorption was present in all groups with no significant difference between them. It was concluded that the canal dressing of calcium hydroxide associated with propolis 10% followed by ultrasonic agitation was not more effective than Ca(OH)2 in the repair process in...

Orthodontic Extrusion as Treatment Option for Crown-Root Fracture: Literature Review with Systematic Criteria.

OBJECTIVE: To review the literature searching for a consensus for the choice of orthodontic extrusion as treatment for crown-root fracture. MATERIALS AND METHODS: 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. RESULTS: 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. CONCLUSION: 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.

Delayed tooth replantation in rats: effect of systemic antibiotic therapy with amoxicillin and tetracycline.

Systemic antibiotic therapy (SAT) has usually been recommended after tooth replantation, but its actual value has been questioned. As there are no reports in the literature about its influence on tooth replantation, the aim of this study was to evaluate the influence of systemic administration of antibiotics (amoxicillin and tetracycline) at the different phases of the repair process (7, 15, 30 days) in delayed rat tooth replantation. Ninety Wistar rats (Rattus norvegicus albinus) had their maxillary right incisors extracted and bench-dried for 60 min. The dental papilla, enamel organ, pulp tissue, and root surface-adhered periodontal ligament were removed, and the teeth were replanted. The animals received no antibiotics (n = 30) or were medicated systemically with amoxicillin (n = 30) and tetracycline (n = 30), and were euthanized after 7, 15, and 30 days. Regardless of the evaluation period, the acute inflammatory infiltrate was less intense and root resorption presented smaller extent and depth in the group treated with amoxicillin. The results suggest that SAT has a positive influence on the repair process in delayed tooth replantation and that amoxicillin is an excellent treatment option.