RESUMO
BACKGROUND/AIM: The aim of this study was to test and validate a new model of extrusive luxation trauma on maxillary first molars of rats. MATERIAL AND METHODS: Forty adult male rats (Rattus norvegicus albinus, Wistar; weight = 230-250 g), 45 days old, were divided into eight groups (n = 5): control groups, in which animals were not subjected to any procedure and waited 1 day (GC1D) or 3 days (GC3D) for euthanasia, and experimental groups, in which animals were subjected to forces of 1100cN, 1300cN, or 1500cN and waited 1 or 3 days for euthanasia (GT1100/1D, GT1100/3D, GT1300/1D, GT1300/3D, GT1500/1D, GT1500/3D). In animals of the experimental groups, trauma was produced by an extrusive force in maxillary first right molars. Four-micrometer serial cuts stained with hematoxylin and eosin (HE) were made. Descriptive microscopic analysis of first upper right molar and semi-quantitative analysis (scores 1 to 4) of intensity of acute and chronic inflammation and vascular changes in the periodontal ligament and active and inactive external root resorption were conducted. The distribution of scores in the groups was compared using the Freeman-Halton extension of Fisher's exact test. The significance level was 5%. RESULTS: It was observed that vascular disorders (bleeding) on the periodontal ligament became more evident with increasing extrusive force. CONCLUSIONS: This new method was capable of generating histological changes, proving its secure application in this research area. The 1500cN force produced more damage on the periodontal ligament. CLINICAL RELEVANCE: The validation of a new experimental method can produce more reliable evidence in further research.
Assuntos
Modelos Animais de Doenças , Dente Molar/lesões , Avulsão Dentária/patologia , Animais , Tecido Conjuntivo/lesões , Tecido Conjuntivo/patologia , Ligadura , Masculino , Maxila , Ligamento Periodontal/lesões , Ligamento Periodontal/patologia , Ratos , Ratos Wistar , Raiz Dentária/lesões , Raiz Dentária/patologiaRESUMO
External Cervical Resorption in maxillary canines with pulp vitality is frequently associated with dental trauma resulting from surgical procedures carried out to prepare the teeth for further orthodontic traction. Preparation procedures might surgically manipulate the cementoenamel junction or cause luxation of teeth due to applying excessive force or movement tests beyond the tolerance limits of periodontal ligament and cervical tissue structures. Dentin exposure at the cementoenamel junction triggers External Cervical Resorption as a result of inflammation followed by antigen recognition of dentin proteins. External Cervical Resorption is painless, does not induce pulpitis and develops slowly. The lesion is generally associated with and covered by gingival soft tissues which disguise normal clinical aspects, thereby leading to late diagnosis when the process is near pulp threshold. Endodontic treatment is recommended only if surgical procedures are rendered necessary in the pulp space; otherwise, External Cervical Resorption should be treated by conservative means: protecting the dental pulp and restoring function and esthetics of teeth whose pulp will remain in normal conditions. Unfortunately, there is a lack of well-grounded research evincing how often External Cervical Resorption associated with canines subjected to orthodontic traction occurs.
A reabsorção cervical externa em caninos superiores com vitalidade pulpar em sua quase totalidade está associada a traumatismo dentário decorrente de procedimentos cirúrgicos associado à preparação desse dente para ser tracionado ortodonticamente. Nessa preparação pode se manipular cirurgicamente a junção amelocementária ou luxar o dente com forças excessivas ou com testes de movimentação além dos limites de tolerância estrutural do ligamento periodontal e tecidos cervicais. A exposição dentinária na junção amelocementária é o estopim para se iniciar uma reabsorção cervical externa a partir de uma inflamação induzida na região seguida de reconhecimento antigênico das proteínas dentinárias. A reabsorção cervical externa é indolor, não induz pulpites e tem uma evolução lenta. Em geral, a lesão está associada e recoberta por tecidos moles gengivais que mantêm, por longos períodos, os aspectos clínicos normais, induzindo diagnósticos tardios, quando o processo se aproxima dos limites pulpares. O tratamento endodôntico está indicado apenas em função de procedimentos operatórios que se fazem necessários no espaço pulpar; caso contrário, a reabsorção cervical externa deve ser tratada de forma conservadora, protegendo a polpa dentária e restaurando a função e estética do dente que permanecerá com sua polpa normal. Infelizmente, não sabemos, com base em pesquisas de casuísticas bem estabelecidas, qual é a frequência da reabsorção cervical externa associada a caninos ortodonticamente tracionados.
Assuntos
Adulto , Humanos , Dente Canino/lesões , Colo do Dente/lesões , Técnicas de Movimentação Dentária/efeitos adversos , Reabsorção de Dente/etiologia , Hidróxido de Cálcio/uso terapêutico , Diagnóstico Diferencial , Dentina/lesões , Ligamento Periodontal/lesões , Radiografia Interproximal , Radiografia Panorâmica , Tomografia Computadorizada por Raios XAssuntos
Humanos , Adolescente , Criança , Traumatismos Dentários/classificação , Traumatismos Dentários/diagnóstico , Traumatismos Dentários/terapia , Acidentes , Alvéolo Dental/lesões , Avulsão Dentária/terapia , Coroa do Dente/lesões , Dentição Mista , Exposição da Polpa Dentária/terapia , Fraturas dos Dentes/terapia , Ligamento Periodontal/lesões , Raiz Dentária/lesões , Dente DecíduoAssuntos
Humanos , Adolescente , Criança , Traumatismos Dentários/classificação , Traumatismos Dentários/terapia , Traumatismos Dentários/diagnóstico , Dente Decíduo , Dentição Mista , Avulsão Dentária/terapia , Fraturas dos Dentes/terapia , Acidentes , Raiz Dentária/lesões , Ligamento Periodontal/lesões , Alvéolo Dental/lesões , Coroa do Dente/lesões , Exposição da Polpa Dentária/terapiaRESUMO
OBJECTIVE: The objective of this study was to assess the histological alterations that occurred in the periodontal area of rat molars submitted to induced tooth movement (ITM) right after an intentional trauma (subluxation). METHODS: Forty adult male Wistar rats (Rattus norvegicus albinus) were selected. The animals were divided into eight groups (n=5), according to the combination of variables: Group 1--control (neither trauma nor ITM); Group 2--ITM; Groups 3, 4, 5 and 6--dentoalveolar trauma groups corresponding, respectively, to 1, 3, 8 and 10 days after trauma; Groups 7 and 8 - the animals' molars were subjected to a 900 cN impact and, one and three days after the trauma event, tooth movement was induced. The rats' maxillary first molars were mesially moved during seven days with a closed coil (50 cN). After the experimental period of each group, the animals were sacrificed by anesthetic overdose and the right maxillas were removed and processed for histological analysis under light microscopy. RESULTS: In the animals of group 3, 4, 5 and 6, the histological alterations were not very significant. Consequently, the effect of induced tooth movement right after a subluxation event (groups 7 and 8) was very similar to those described for Group 2. CONCLUSIONS: There was no difference in the quality of periodontal repair when ITM was applied to teeth that had suffered a subluxation trauma.
Assuntos
Dente Molar/lesões , Avulsão Dentária/patologia , Técnicas de Movimentação Dentária/métodos , Perda do Osso Alveolar/patologia , Processo Alveolar/lesões , Processo Alveolar/patologia , Animais , Colágeno , Cemento Dentário/lesões , Cemento Dentário/patologia , Dentina/patologia , Fibroblastos/patologia , Masculino , Dente Molar/patologia , Fios Ortodônticos , Ligamento Periodontal/lesões , Ligamento Periodontal/patologia , Periodonto/lesões , Periodonto/patologia , Ratos , Ratos Wistar , Reabsorção da Raiz/patologia , Fatores de Tempo , Anquilose Dental/patologia , Ápice Dentário/patologia , Técnicas de Movimentação Dentária/instrumentação , Raiz Dentária/lesões , Raiz Dentária/patologia , Cicatrização/fisiologiaRESUMO
OBJECTIVE: The objective of this study was to assess the histological alterations that occurred in the periodontal area of rat molars submitted to induced tooth movement (ITM) right after an intentional trauma (subluxation). METHODS: Forty adult male Wistar rats (Rattus norvegicus albinus) were selected. The animals were divided into eight groups (n = 5), according to the combination of variables: Group 1 - control (neither trauma nor ITM); Group 2 - ITM; Groups 3, 4, 5 and 6 - dentoalveolar trauma groups corresponding, respectively, to 1, 3, 8 and 10 days after trauma; Groups 7 and 8 - the animals' molars were subjected to a 900 cN impact and, one and three days after the trauma event, tooth movement was induced. The rats' maxillary first molars were mesially moved during seven days with a closed coil (50 cN). After the experimental period of each group, the animals were sacrificed by anesthetic overdose and the right maxillas were removed and processed for histological analysis under light microscopy. RESULTS: In the animals of group 3, 4, 5 and 6, the histological alterations were not very significant. Consequently, the effect of induced tooth movement right after a subluxation event (groups 7 and 8) was very similar to those described for Group 2. CONCLUSION: There was no difference in the quality of periodontal repair when ITM was applied to teeth that had suffered a subluxation trauma. .
OBJETIVO: avaliar as alterações histológicas ocorridas na área periodontal de molares de ratos submetidos à movimentação dentária induzida (MDI), logo após um trauma intencional (subluxação). MÉTODOS: quarenta ratos Wistar machos adultos (Rattus norvegicus albinus) foram selecionados. Os animais foram divididos em oito grupos (n = 5), de acordo com a combinação das variáveis: Grupo 1 - controle (sem trauma e sem MDI); Grupo 2 - MDI; Grupos 3, 4, 5 e 6 - grupos de trauma dentoalveolar correspondendo, respectivamente, para 1, 3, 8 e 10 dias após o trauma; Grupos 7 e 8 - os molares murinos foram submetidos a um impacto de 900cN e, de um e três dias após o evento trauma, o movimento do dente foi induzido. Os primeiros molares superiores dos animais foram movidos mesialmente durante sete dias, com uma mola fechada (50cN). Após período experimental de cada grupo, os animais foram sacrificados por overdose anestésica e as maxilas direitas foram removidas e processadas para análise histológica qualitativa. RESULTADOS: nos animais dos grupos 3, 4, 5 e 6, as alterações histológicas não foram muito significativas. Consequentemente, o efeito do movimento dentário induzido logo após um evento de subluxação (grupos 7 e 8) foi muito semelhante ao descrito para o grupo 2. CONCLUSÃO: não houve diferença na qualidade do reparo periodontal quando a MDI foi aplicada aos dentes que sofreram um trauma de subluxação. .
Assuntos
Animais , Masculino , Ratos , Dente Molar/lesões , Avulsão Dentária/patologia , Técnicas de Movimentação Dentária/métodos , Perda do Osso Alveolar/patologia , Processo Alveolar/lesões , Processo Alveolar/patologia , Colágeno , Cemento Dentário/lesões , Cemento Dentário/patologia , Dentina/patologia , Fibroblastos/patologia , Dente Molar/patologia , Fios Ortodônticos , Ligamento Periodontal/lesões , Ligamento Periodontal/patologia , Periodonto/lesões , Periodonto/patologia , Ratos Wistar , Reabsorção da Raiz/patologia , Fatores de Tempo , Anquilose Dental/patologia , Ápice Dentário/patologia , Técnicas de Movimentação Dentária/instrumentação , Raiz Dentária/lesões , Raiz Dentária/patologia , Cicatrização/fisiologiaRESUMO
External Cervical Resorption in maxillary canines with pulp vitality is frequently associated with dental trauma resulting from surgical procedures carried out to prepare the teeth for further orthodontic traction. Preparation procedures might surgically manipulate the cementoenamel junction or cause luxation of teeth due to applying excessive force or movement tests beyond the tolerance limits of periodontal ligament and cervical tissue structures. Dentin exposure at the cementoenamel junction triggers External Cervical Resorption as a result of inflammation followed by antigen recognition of dentin proteins. External Cervical Resorption is painless, does not induce pulpitis and develops slowly. The lesion is generally associated with and covered by gingival soft tissues which disguise normal clinical aspects, thereby leading to late diagnosis when the process is near pulp threshold. Endodontic treatment is recommended only if surgical procedures are rendered necessary in the pulp space; otherwise, External Cervical Resorption should be treated by conservative means: protecting the dental pulp and restoring function and esthetics of teeth whose pulp will remain in normal conditions. Unfortunately, there is a lack of well-grounded research evincing how often External Cervical Resorption associated with canines subjected to orthodontic traction occurs.
Assuntos
Dente Canino/lesões , Colo do Dente/lesões , Técnicas de Movimentação Dentária/efeitos adversos , Reabsorção de Dente/etiologia , Adulto , Hidróxido de Cálcio/uso terapêutico , Dentina/lesões , Diagnóstico Diferencial , Humanos , Ligamento Periodontal/lesões , Radiografia Interproximal , Radiografia Panorâmica , Tomografia Computadorizada por Raios XRESUMO
This study describes how periodontology, endodontology, and dentistry were integrated for the coronal reconstruction of anterior teeth extensively destroyed by dental trauma. A 15-year-old girl suffered a bicycle accident that resulted in the fracture of teeth No. 8 and 9. Clinical and radiographic examinations confirmed coronal fracture in both teeth, in addition to compromised pulp vitality, invasion of the biologic periodontal space, and loss of coronal space due to mesialization of the neighboring teeth. The protocol consisted of endodontic treatment for the fractured teeth, periodontal surgery to augment the clinical crown and gingival recontouring, intracanal cementation of esthetic glass fiber posts, and coronal reconstruction with resin composite. At a longitudinal follow-up visit 1 year later, clinical and radiographic examinations revealed successful rehabilitation of the fractured teeth.
Assuntos
Restauração Dentária Permanente/métodos , Incisivo/lesões , Planejamento de Assistência ao Paciente , Equipe de Assistência ao Paciente , Coroa do Dente/lesões , Fraturas dos Dentes/cirurgia , Adolescente , Ciclismo/lesões , Resinas Compostas/química , Aumento da Coroa Clínica/métodos , Coroas , Materiais Dentários/química , Polpa Dentária/lesões , Estética Dentária , Feminino , Seguimentos , Gengivoplastia/métodos , Vidro/química , Humanos , Ligamento Periodontal/lesões , Técnica para Retentor Intrarradicular/instrumentação , Tratamento do Canal Radicular/métodosRESUMO
Dental tissues have special characteristics, and its regenerative capacity is noteworthy. However, understanding the circumstances that lead to regeneration is challenging. In this study, the chronology of the healing process after immediate replantation of rat incisor teeth was examined by histological and immunohistochemical analyses within a 60-day period. Thirty-six male Wistar rats had their maxillary right incisors extracted and replanted after 15 min in saline storage. The rats were sacrificed immediately 3, 7, 15, 28, and 60 days after replantation. The histological analysis showed rupture of the periodontal ligament and formation of a blood clot, which started being replaced by a connective tissue after 3 days. At 7 days, the gingival mucosa epithelium was reinserted and areas of root resorption could be seen. At 15 days, the periodontal ligament was repaired. At 3 days, the pulp presented an absence of the odontoblast layer, which started being replaced by a connective tissue. This tissue suffered gradual calcification, filling the root canal at 28 and 60 days. The root ends were closed. The immunohistochemical analysis revealed greater expression of OP, OPG, and RANK proteins in the initial periods (0 and 3 days), while TRAP expression predominated at 28 and 60 days (P < 0.05). In conclusion, in delayed tooth replantation, there is great new bone formation activity in the earlier periods of the repair process, while a predominance of bone resorption and remodeling is observed in the more advanced periods.
Assuntos
Incisivo/lesões , Reimplante Dentário/métodos , Fosfatase Ácida/análise , Animais , Biomarcadores/análise , Coagulação Sanguínea/fisiologia , Colágeno , Tecido Conjuntivo/patologia , Polpa Dentária/patologia , Calcificações da Polpa Dentária/etiologia , Calcificações da Polpa Dentária/patologia , Epitélio/patologia , Gengiva/patologia , Imuno-Histoquímica , Isoenzimas/análise , Masculino , Odontoblastos/patologia , Osteopontina/análise , Osteoprotegerina/análise , Ligamento Periodontal/lesões , Ligamento Periodontal/patologia , Ligante RANK/análise , Ratos , Ratos Wistar , Receptor Ativador de Fator Nuclear kappa-B/análise , Reabsorção da Raiz/etiologia , Reabsorção da Raiz/patologia , Ruptura , Fosfatase Ácida Resistente a Tartarato , Fatores de Tempo , Ápice Dentário/patologia , Alvéolo Dental/patologia , Cicatrização/fisiologiaRESUMO
This study investigated the level of knowledge held by dentists about the possible treatment plan procedures for periodontal ligament injuries after dentoalveolar trauma. A 5-item self-applied questionnaire was prepared with questions referring to the professional profile of the interviewees and to the treatment plan they would propose for periodontal ligament injuries secondary to dentoalveolar trauma. The questionnaires were filled out by 693 dentists attending the 23rd Annual Meeting of the Brazilian Society for Dental Research, and the data obtained were subjected to descriptive analysis. Either the chi-square test or Fisher's exact test was applied to assess associations among variables, at a 5% level of significance. The results revealed that dentists experienced difficulty in establishing a treatment plan for subluxation, and for extrusive, lateral and intrusive luxations. In general, holding a dental specialty degree had no influence on the knowledge about treatment plan procedures for the most severe injuries. It could be concluded that the dentists participating in this study, whether specialists or not, did not have sufficient knowledge to treat most of the periodontal ligament injuries resulting from dentoalveolar trauma adequately.