Histological changes in pulp-dentin complex in tooth subjected to traumatic occlusion and subluxation.

Background: This study evaluated the influence of traumatic occlusion in the dentin-pulp complex a molar teeth submitted to subluxation. Material and methods: Ninety Wistar rats were divided into groups Naïve (N), Subluxation (S) and Subluxation with traumatic occlusion (STO) and submitted to histological analysis after 7 and 21 days. A quantitative analysis was submitted to one-way ANOVA and Tukey's post-hoc test, and Chi-square and Bonferronís post-hoc test. Results: S and STO showed a significant increase in blood vessels area (p < 0.0005), amorphous fundamental substance (p < 0.0005) and reactionary dentin formation (p < 0.0005), as well as a decrease in the nuclear profile (p < 0.0005), odontoblast layer (p = 0.013 and p < 0.0005) by day 7 when compared with N. These changes normalized by day 21, except for the reactionary dentin (p < 0.0005) in both S and STO groups. Interestingly, the STO group exhibited significant changes in the increase of pulp calcification (p < 0.0005), presence of tubules with nuclei (p < 0.0005), and inflammatory infiltrate (p < 0.0005), as well reduction of nuclear profile (p < 0.0005), odontoblast layer (p < 0.0005) compared with N and S at day 21. Conclusions: STO impaired the defence response and decreased pulp regeneration capacity by increasing the inflammatory infiltrate and pulp calcification, and decreasing the nucleated cell number in the odontoblast layer and central pulp.

Multiple external root resorptions in a patient with Stage IV, Grade C periodontitis and autoimmune diseases: A case report.

BACKGROUND: Pathological root resorption affects permanent teeth and is usually triggered by infectious-inflammatory stimuli and/or dental trauma. Periodontitis and traumatic occlusion have been reported as possible causative factors of root resorptions, whilst the impact of systemic diseases is less well understood. This case highlights the need for consideration of multiple risk factors, especially when presenting in combination. METHODS AND RESULTS: A 62-year-old South Asian female presented with unstable Stage IV Grade C periodontitis, poor oral hygiene and multiple autoimmune conditions including oral lichen planus. Clinical and radiographic examination revealed multiple advanced apical and external root resorptions of the patient's molars associated with periapical bone loss, despite of a minimally restored dental status. CONCLUSION: A likely etiology of this patient's multiple root resorptions is the presence of unstable periodontitis with periodontal-endodontic lesions, exacerbated by a dysbalanced immune response to infectious agents. Appropriate monitoring and managing of such patients can prevent or limit the pathological process of inflammatory root resorption. KEY POINTS: Why is this case new information? This is the first report documenting advanced multiple external inflammatory root resorptions in a periodontitis patient with oral and systemic co-morbidities. What are the keys to successful management of this case? Early diagnosis, prevention and intervention to limit periodontal inflammation, endodontic infection and occlusal trauma. What are the primary limitations to success in this case? Late diagnosis of multiple root resorptions, palliative periodontal treatment due to poor oral hygiene compliance, and poorly controlled systemic inflammation favoring the persistence of a dysregulated immune response to the oral microbiota.

Occlusal Trauma Induces Neuroimmune Crosstalk for a Pain State.

Temporomandibular joint (TMJ) disorder caused by occlusal trauma is one of the most controversial topics in dentistry. Experimental traumatic occlusion (ETO) induced by metal crowns cemented to mandibular first molars in rats causes a long-lasting nociceptive response. This study aimed to elucidate whether ETO generates an increase in inflammatory mediators in the TMJ. In addition, the impact of ETO on trigeminal ganglia, neurotransmitter release, and satellite glial cell (SGC) activation was investigated. ELISA revealed enhanced inflammatory mediators, including TNF-α, IL-1ß, IL-6, CX3CL1, and ADAM-17 by Western blotting, in periarticular TMJ tissue after 28 d of ETO. In the trigeminal ganglia, ETO groups increased the release of the neurotransmitters substance P and glutamate. Overexpression of the AMPA receptor and upregulation of NMDA were observed in the 0.4- and 0.7-mm ETO groups, respectively, highlighting enhanced neuronal excitation. Increased IL-1ß and COX-2 mRNA levels in the 0.7-mm ETO group confirmed trigeminal ganglia SGC activation. Immunofluorescence and electrophoresis of SGC revealed increased pERK expression in the 0.7-mm ETO group. ERK phosphorylation was shown to be nociceptive specific, with its upregulation occurring in cases of chronic inflammatory pain. Increased PKA mRNA levels were observed in the 0.4-mm ETO group, while CREB mRNA levels were upregulated for both ETO groups. Electrophoresis showed overexpression of sodium channel Nav 1.7 in the 0.7-mm ETO group, while immunofluorescence revealed that Nav 1.7 is expressed in sensory trigeminal ganglia cells. The results of this study suggest that occlusal trauma induces neuroimmune crosstalk, with synthesis of proinflammatory/pronociceptive mediators, which increases neuronal activity in trigeminal ganglia via the activation of an inflammatory response cascade to develop a persistent neuroinflammatory state that leads to central sensitization.

Non-surgical Treatment of Condylar Fracture in an 11-Year-Old Patient: a Case Report.

BACKGROUND: Mandibular condylar fractures commonly occur after trauma and account for 25 to 35% of all mandibular fractures; its appropriate therapy still remains a point of controversy in children. The purpose of this paper is to describe the treatment of an 11-years-old male patient affected by neck-condylar fracture as result of trauma in evolutive age. METHODS: No surgical treatment was performed. A functional therapy was applied with a jaw splint. A closed treatment for mandibular condyle fractures was preferred because the amount of condylar displacement wasn't considerable. RESULTS: The early treatment with functional therapy generated a functional adaptation of the condyle in the glenoid fossa and a normal mandibular function. After a 12-month follow-up the fracture resolution and an optimal condylar position were recorded. CONCLUSIONS: The current case report and literature review showed that non-surgical therapy of neck-condylar fracture in a child with lower resin splint can restore mandibular movements and aesthetics. Facial growth after one year treatment resulted normal. A conservative treatment may be appropriate for children in selected cases with minimally displaced condyle.

Influência da oclusão traumática no processo de reparo do periodonto em dentes submetidos a luxação extrusiva / Influence of traumatic occlusion on the periodontal repair process in teeth submitted to extrusive luxation

O tratamento luxação extrusiva visa o reparo das estruturas de suporte do periodonto com o dente em posição original, contudo pode ser prejudicado por alguns fatores como a oclusão traumática. Este estudo avaliou a influência da oclusão traumática no processo de reparo dos tecidos de suporte periodontais de dentes que sofreram luxação extrusiva. Sessenta ratos Winstar foram divididos em três grupos: Grupo Controle (n=20), Grupo Luxação Extrusiva (n=20) e Grupo Luxação Extrusiva e Oclusão Traumática (n=20), nos períodos experimentais de 7 e 30 dias. O dente de estudo foi o primeiro molar inferior direito. A luxação extrusiva foi simulada pela indução de forças no sentido axial até o seu deslocamento e reposição do dente por pressão digital. A oclusão traumática foi induzida por restauração de resina composta e fio metálico na superfície oclusal, criando uma plataforma plana.Cortes histológicos longitudinais foram corados com hematoxilina e eosina, Picrosirius red e técnica imunoistoquímica para detecção da TRAcP. Foi avaliada a reabsorção óssea e dentária, área de fibras colágenas, matriz extracelular não fibrilar e vasos sanguíneos, número de perfil nuclear e células TRAcP, organização do ligamento periodontal, extensão e intensidade do processo inflamatório. O teste de Kruskal-Wallis e post hoc de Dunn foram utilizados para a comparação entre os grupos (α=0,05). Dentre as diferenças significativas observou-se: aos 7 dias um aumento de células TRAcP e uma diminuição da área óssea do septo inter-radicular em L e LOT, bem como um aumento da reabsorção óssea marginal no grupo LOT quando comparado ao grupo controle; aos 30 dias, as fibras colágenas tipo I tiveram um aumento no grupo L, bem como, aumento da reabsorção óssea marginal nos grupos experimentais. No modelo experimental estudado, a oclusão traumática gerou prejuízo significativo na recuperação nas estruturas de suporte do dente submetido a luxação extrusiva a curto prazo(AU)

The extrusive luxation treatment aims to repair the structures of the periodontium with the tooth in original position, however it can be impaired by some factors such as traumatic occlusion. This study aims to evaluate the influence of traumatic occlusion on the repairing process of the periodontal tissues of the tooth submitted to extruded luxation. Sixty Winstar rats was divided into three groups: Control group (n=20), Extrusive luxation group (n=20) and Extrusive luxation and Traumatic Occlusion group(=20), in the experimental periods of 7 and 30 days. The experimental tooth was the first lower right molar. The extrusive luxation was simulated by the induction of forces in the axial direction until its displacement and replacement of the tooth by digital pressure. Traumatic occlusion was induced by restoration of composite resin and metallic wire on the occlusal surface, creating a flat platform. Longitudinal histological sections were stained with hematoxylin and eosin, Picrosirius red and immunohistochemical technique for the detection of TRAcP. Bone and dental resorption, area of collagen fibers, extracellular non-fibrillar matrix and blood vessels, number of nuclear profile and TRAcP cells, periodontal ligament organization, extent and intensity of the inflammatory process were evaluated. The Kruskal-Wallis and post hoc Dunn tests were used to compare the groups (α = 0.05). Among the significant differences were observed at 7 days an increase of TRAcP cells and a decrease of the interradicular septum bone area in the L and LTO groups, as well as an increase in the marginal bone resorption in the LTO group when compared to the control group; at 30 days, type I collagen fibers had an increase in the L group, as well as increased marginal bone resorption in the experimental groups. In the experimental model studied, traumatic occlusion generate a significanty impairment in the recovery of the periodontal support structures of the tooth submitted to extrusive luxation in a short period(AU)

Stability of periodontally compromised teeth after splint and non-surgical therapy: two cases followed-up for 1 to 3 years

This article describes cases of applying non-surgical treatment including scaling and root planing, occlusal adjustment and tooth splinting of periodontally compromised lower anterior incisors Clinical and radiographic evaluations were performed over a 1–3-year period. All clinical parameters and radiographic bone levels improved in both cases. Dramatic regeneration of alveolar bone and lamina dura were observed on radiographic images, and no specific complications occurred during the follow-up period. Within the limitations of this study, these cases demonstrated the possibility of tooth rescue through non-surgical treatment and splinting of periodontally compromised teeth typically considered for extraction.

Uso de contenção com fibra de vidro imersa em resina composta para contenção periodontal ­ relato de caso / Glass fiber-reinforced composite resin for tooth stabilization ­ case report

Este trabalho descreve, por meio de um relato de caso clínico, a aplicação clínica de uma contenção com fibra de vidro trançada impregnada em resina composta para tratamento de periodontite crônica severa associada à oclusão traumática. Paciente do gênero masculino, com 46 anos de idade, apresentou-se com queixa de sangramento gengival e desconforto mastigatório na região anterior superior. A avaliação clínica e a radiográfica demonstraram mobilidade grau 2, perda óssea vertical e aumento do espaço do ligamento periodontal. O tratamento preconizado foi o acesso cirúrgico para raspagem e alisamento radicular associado à contenção com fibra de vidro trançada impregnada em resina composta de canino a canino superior. Os acompanhamentos clínico e radiográfico de 18 meses demonstraram resultados favoráveis com relação à saúde periodontal e manutenção dos aspectos funcionais e estéticos. A contenção por meio de fibra de vidro trançada impregnada em resina composta é uma técnica viável e estável para a estabilização de dentes com perda óssea periodontal (AU).

The present case report describes the clinical application of splinting with glass fiberreinforced composite resin for the treatment of the secondary occlusal trauma in a patient with severe chronic periodontitis. A male patient, 46 years old, presented with gingival bleeding and masticatory discomfort complaints related to the upper anterior region. Clinical and radiographic evaluation showed grade 2 dental mobility, bone loss and increased periodontal ligament space. The proposed treatment was periodontal surgery for scaling and root planning associated to splinting with glass fiber-reinforced composite resin from right upper canine to upper lower canine. The 18 months follow-up showed favorable clinical and radiographic results with respect to periodontal health and maintenance of esthetic and functional aspects. The splinting with glass fiber-reinforced composite resin is a viable technique and stable over time for stabilizing tooth with periodontal bone loss (AU).

The influence of primary occlusal trauma on the development of gingival recession / La influencia del trauma oclusal primario en el desarrollo de la recesión gingival

This study aimed to histometrically evaluate the presence of gingival recession in the mesial surface of the teeth of rats experimentally subjected to primary occlusal trauma. This evaluation verified the distance from the cement-enamel junction (CEJ) to the free marginal gingiva (FMG) and to the height of the alveolar bone crest (CEJ-crest bone distance). There were 10 animals, randomly divided into 2 groups: occlusal trauma (OT) (n = 5) - creation of an occlusal interference by fixing an orthodontic wire segment on the mandibular first molar occlusal face, which was randomly chosen, and a Control Group (CG) (n = 5) - five animals with no exposure to the OT variable were euthanised after 14 days to obtain the initial parameters. The inter-group evaluation showed there was no significant difference between OT × CG when the CEJ-FGM distance (P = 0.192) was evaluated after 14 days, but there was a significant difference between the two groups as regards the CEJ-alveolar crest bone distance (P = 0.0142). Thus, it can be concluded that the OT induction model, after 14 days of experiment, promoted bone resorption. This was observed by the increase in the CEJ-alveolar crest bone distance. It also did not promote gingival recession, which was evaluated by the CEJ-FGM distance.

El objetivo de este estudio fue evaluar histométricamente en ratas la presencia de recesión gingival en la superficie mesial de los dientes sometidos experimentalmente a trauma oclusal primario a partir de la evaluación de la distancia desde la unión esmalte cemento (CEJ) a la encía marginal libre y la altura de la cresta ósea restante (distancia de la CEJ-cresta ósea) Con este fin, 10 animales fueron divididos al azar en 2 grupos: trauma oclusal (TO) (n = 5) - creación de una interferencia oclusal mediante la fijación de un segmento de alambre de ortodoncia en la superficie oclusal del primer molar elegido al azar; y un grupo control (CO) (n = 5) -5 animales sin la introducción de la variable TO fueron sometidos a eutanasia después de 14 días para obtener los parámetros iniciales. La evaluación intergrupo no mostró diferencias significativas entre los grupos TO × CO al evaluar después de 14 días la distancia de la CEJ-encía marginal libre (p = 0,192) pero mostró una diferencia significativa entre los grupos TO × CO en cuanto a distancia de la CEJ-cresta ósea alveolar (p = 0,0142). Por lo tanto, se concluye que el modelo de inducción del TO después de 14 días del experimento promueve reabsorción ósea siendo observado por el aumento en la distancia de la CEJ-cresta ósea alveolar y no promueve la recesión gingival evaluada a partir de la distancia de la CEJ-encía marginal.

Evaluation of bone loss due to primary occlusal trauma in two experimental models of occlusal overload / Avaliação da reabsorção óssea promovida pelo trauma oclusal primário em dois modelos experimentais de sobrecarga oclusal

Introduction: Primary occlusal trauma (OT) is an injury of the periodontium with normal height as a result of occlusal forces which exceed their adaptive capacity. Objective: To evaluate, histometrically, the alveolar bone loss in the furcation region of rats experimentally submitted to 2 models of occlusal overload. Material and method: 45 animals randomly divided into 3 groups: Occlusal Interference (OI, n = 15) - fixing an orthodontic wire segment on the occlusal surface of the first lower molar; Occlusal Overload (OO, n = 15) - wearing of the cusps of the lower contralateral molars, the second and third molars next to the first molar that had its dimensions maintained; Negative Control (NC, n = 15) - evaluation of the initial dimensions of the periodontal ligament (PL). Five animals / group were sacrificed after 14, 21 and 28 days. Result: Intergroup evaluation showed significant bone loss in OI (p<0.001) and OO (p<0.01) compared to NC. OI had significantly higher bone loss compared to OO at 14 (p<0.01), 21 (p <0.01) and 28 days (p<0.01). The intragroup evaluation showed no significant influence of time on bone loss in OI and OO, regardless of the technique used (p>0.05). The thickness of the PL remained stable in NC (p>0.05). Conclusion: OI and OO were effective in the experimental reproduction of OT, and OI promoted greater alveolar bone loss compared to OO, showing that the impact of occlusal overload in OI increased the extent of the OT injury.

Introdução: Trauma oclusal primário (TO) é a injúria causada no periodonto de inserção de dentes com periodonto de altura normal devido a forças oclusais que excedem sua capacidade adaptativa. Objetivo: Avaliar histometricamente a reabsorção óssea alveolar na região da furca do 1º molar inferior em ratos submetidos experimentalmente a 2 modelos de sobrecarga oclusal. Material e método: 45 animais aleatoriamente divididos em 3 Grupos: Interferência Oclusal (GI, n = 15) - fixação de um segmento de fio ortodôntico na face oclusal do 1º molar inferior; Sobrecarga Oclusal (GS, n = 15) - desgaste das cúspides dos molares inferiores contralaterais e dos 2º e 3º molares do lado do 1º molar que teve suas dimensões mantidas; Grupo Controle Negativo (CN, n = 15) - avaliação das dimensões iniciais do ligamento periodontal. Cinco animais/grupo foram submetidos à eutanásia após 14, 21 e 28 dias. Resultado: A avaliação intergrupos mostrou que houve reabsorção óssea significativa em GI (p<0,001) e GS (p<0,01) quando comparados com CN. O grupo GI teve reabsorção óssea significativamente maior quando comparado ao grupo GS em 14 (p<0,01), 21 (p<0,01) e 28 dias (p<0,01). A avaliação intragrupos não mostrou influência significativa do tempo na reabsorção óssea em GI e GS, independente da técnica utilizada (p>0,05). A espessura do ligamento periodontal manteve-se estável no grupo CN (p>0,05). Conclusão: GI e GS foram eficazes na reprodução experimental do TO e GI promoveu maior reabsorção óssea alveolar quando comparado a GS, mostrando que o impacto causado pela sobrecarga oclusal no grupo GI aumentou a lesão por TO.

Efeito das forças oclusais excessivas sobre os dentes e o periodonto de inserção / Effect of excessive occlusal forces on teeth and the supporting periodontium

Os dentes e o periodonto respondem com alterações funcionais adaptativas às forças mastigatórias. Porém, estudos clínicos têm mostrado que forças oclusais excessivas podem causar injúria aos tecidos de suporte do dente, com alterações clínicas como mobilidade e migração dental, trincas de esmalte, sensibilidade térmica e frêmito. Estudos pré-clínicos em animais também têm mostrado alterações histológicas frente às forças oclusais excessivas, como espessamento do ligamento periodontal, radioluscência no ápice de dentes vitais, reabsorção óssea e radicular. Tais alterações, conhecidas como trauma oclusal, são reversíveis quando não há inflamação instalada e as forças excessivas são removidas. Por outro lado, a literatura é controversa no que se refere à relação entre o trauma oclusal e o início e progressão da doença periodontal. O presente estudo teve como objetivo revisar a literatura a respeito do efeito das forças oclusais excessivas incidentes sobre os dentes e o periodonto de inserção, em condições saudáveis ou quando o suporte encontra-se inadequado ou reduzido.

Teeth and periodontium answer with adaptive alterations to the masticatory forces. However, clinical studies have shown that excessive occlusal forces may cause an injury in the supporting tissues of the tooth, causing clinical alterations such as tooth mobility and migration, enamel cracks, thermal sensitivity and fremitus. Pre-clinical studies in animals have shown histological alterations such as widening of the periodontal ligament, radiolucency at the apex of vital teeth, bone and root resorption. These alterations, known as occlusal trauma, are reversible when there is no inflammation and the excessive forces are removed. On the other hand, literature is controversial regarding the association between the occlusal trauma and the beginning and progression of the periodontal disease. This study aimed to review the literature regarding the effect of the excessive occlusal forces on the teeth and on the insertion periodontium, under healthy conditions and inadequate or reduced support.

Rescue of a periodontally compromised tooth by non-surgical treatment: a case report.

PURPOSE: This article describes a case of the successful non-surgical management of a periodontally compromised maxillary premolar. METHODS: A combination therapy, including root planing, occlusal adjustment, and tooth splinting, was applied. Clinical and radiographic examinations were performed during the 16-month follow-up period. RESULTS: All periodontal parameters were improved. There were dramatic decreases (3-6 mm) in the probing pocket depth, tooth mobility, and marginal bone loss. Interestingly, gradual resolution of the periapical radiolucency and alveolar bone regeneration were observed in the radiographs, and the periodontal condition was maintained during the follow-up period. CONCLUSIONS: Within the limits of this study, these results demonstrate the importance of natural tooth preservation through proper periodontal treatment and occlusal adjustment of the periodontally compromised tooth, which is typically targeted for tooth extraction and dental implantation.

Influência da oclusão dentária em ratos submetidos a reimplante imediato: estudo histológico do periodonto e imuno-histoquimíco dos restos epiteliais de malassez e células clásticas / Influence of dental occlusion in the periodontium of the teeth rats submitted to immediately replantation: study of epithelial remains of malassez and clastic cells

Alguns fatores podem interferir no prognóstico do reimplante imediato, como a fase da rizogênese dentária, o período de tempo no meio extra-alveolar, meios de conservação, contaminação, o uso e tipo de contenção dentária e a oclusão traumática. Este estudo visa avaliar a influência da ausência ou excesso de carga oclusal no processo de reparo do periodonto, com ênfase nas características histológicas, e analisar dos restos epiteliais de Malassez e das células clásticas na raiz mesial do primeiro molar superior de ratos submetidos a reimplante imediato. Foram divididos em grupos controle (GC),infra-oclusão (GIO) e oclusão traumática (GOT) e os períodos experimentais avaliados de 3, 5, 7, 14 e 30 dias. Análises qualitativas e quantitativas foram realizadas em cortes histológicos corados pelo método da hematoxilina e eosina (HE); e células clásticas (fosfatase ácida resistente ao tartarato, TRAP) e os restos epiteliais de malassez (citoqueratina) pela técnica de imuno-histoquímica. Os dados foram submetidos ao teste de Kruskal-Wallis e pósteste de Dunn, considerando p< 0,05 como significante. No período de 5 dias, os animais do grupo GIO apresentaram espessura do ligamento periodontal e porcentagem da área de matriz extracelular fibrilar e não fibrilar significativamente menor. No 7º dia, animais do GIO mostraram uma redução significativa da porcentagem da área de matriz extracelular não fibrilar e número de células clástica, sendo o oposto no grupo GOT. Aos 30 dias a porcentagem de matriz extracelular não fibrilar e número de células clástica foram menores, e o número de perfil nuclear foi maior no GIO. A oclusão traumática aumentou significativamente o número de células clásticas, enquanto a ausência de forças oclusais retardou o aparecimento e o número das mesmas. Os restos epiteliais de Malassez foram evidenciados, principalmente presente no período de 3 dias pós-operatório e, raramente visualizados nos demais tempos experimentais. Em conclusão, baseado...

Among the factors that can interfere in the immediate tooth replantation prognosis there are the phase of root formation, the extra-alveolar period, storage media, contamination, use and type of dental splint and traumatic occlusion. This study aims to evaluate the influence of absence or excessive occlusal load on periodontal healing process, with emphasis on homeostatic function of epithelial remains of Malassez and clastic cells, dental root of rat molars submitted of immediate replantation. We used 150 male rats , with 5 weeks of life, divided into Control group ( GC ) infra occlusion ( IOG) and traumatic occlusion ( TOG) and the experimental periods evaluated 3, 5, 7, 14 and 30 days.Qualitative and quantitative analyzes were performed on histological sections stained by hematoxylin and eosin (HE); and clastic cells (TRAP) and epithelial remains of Malassez (PAN Cytokeratin) by immunohistochemistry. The data were submitted to the Kruskal-Wallis test post hoc Dunn, the statistical program Graph Prism 6.0 (α = 5%). The epithelial remains of Malassez were present in the 3-day period and absent in other experimental times, in all the groups. In the 5-day period IOG shows thickness of the periodontal ligament and the percentage of fibrillar and non fibrillar extracellular matrix area significantly lower. On the 7th day IOG showed a significant reduction of the percentage of non fibrillar extracellular matrix area and clastic number of cells, and OTG shows the opposite. At 30 days the percentage of non-fibrillar extracellular matrix and the number of clastic cells was lower, and the number of cell profiles was higher in IOG. The traumatic occlusion significantly increases the number of clastic cells, while the absence of occlusal forces retards the onset and the number of them. Early occlusal load should be avoided in the teeth subjected to immediate replantation

Influência da oclusão dentária em ratos submetidos a reimplante imediato: estudo histológico do periodonto e imuno-histoquimíco dos restos epiteliais de malassez e células clásticas / Influence of dental occlusion in the periodontium of the teeth rats submitted to immediately replantation: study of epithelial remains of malassez and clastic cells

Alguns fatores podem interferir no prognóstico do reimplante imediato, como a fase da rizogênese dentária, o período de tempo no meio extra-alveolar, meios de conservação, contaminação, o uso e tipo de contenção dentária e a oclusão traumática. Este estudo visa avaliar a influência da ausência ou excesso de carga oclusal no processo de reparo do periodonto, com ênfase nas características histológicas, e analisar dos restos epiteliais de Malassez e das células clásticas na raiz mesial do primeiro molar superior de ratos submetidos a reimplante imediato. Foram divididos em grupos controle (GC),infra-oclusão (GIO) e oclusão traumática (GOT) e os períodos experimentais avaliados de 3, 5, 7, 14 e 30 dias. Análises qualitativas e quantitativas foram realizadas em cortes histológicos corados pelo método da hematoxilina e eosina (HE); e células clásticas (fosfatase ácida resistente ao tartarato, TRAP) e os restos epiteliais de malassez (citoqueratina) pela técnica de imuno-histoquímica. Os dados foram submetidos ao teste de Kruskal-Wallis e pósteste de Dunn, considerando p< 0,05 como significante. No período de 5 dias, os animais do grupo GIO apresentaram espessura do ligamento periodontal e porcentagem da área de matriz extracelular fibrilar e não fibrilar significativamente menor. No 7º dia, animais do GIO mostraram uma redução significativa da porcentagem da área de matriz extracelular não fibrilar e número de células clástica, sendo o oposto no grupo GOT. Aos 30 dias a porcentagem de matriz extracelular não fibrilar e número de células clástica foram menores, e o número de perfil nuclear foi maior no GIO. A oclusão traumática aumentou significativamente o número de células clásticas, enquanto a ausência de forças oclusais retardou o aparecimento e o número das mesmas. Os restos epiteliais de Malassez foram evidenciados, principalmente presente no período de 3 dias pós-operatório e, raramente visualizados nos demais tempos experimentais. Em conclusão, baseado...

Among the factors that can interfere in the immediate tooth replantation prognosis there are the phase of root formation, the extra-alveolar period, storage media, contamination, use and type of dental splint and traumatic occlusion. This study aims to evaluate the influence of absence or excessive occlusal load on periodontal healing process, with emphasis on homeostatic function of epithelial remains of Malassez and clastic cells, dental root of rat molars submitted of immediate replantation. We used 150 male rats , with 5 weeks of life, divided into Control group ( GC ) infra occlusion ( IOG) and traumatic occlusion ( TOG) and the experimental periods evaluated 3, 5, 7, 14 and 30 days.Qualitative and quantitative analyzes were performed on histological sections stained by hematoxylin and eosin (HE); and clastic cells (TRAP) and epithelial remains of Malassez (PAN Cytokeratin) by immunohistochemistry. The data were submitted to the Kruskal-Wallis test post hoc Dunn, the statistical program Graph Prism 6.0 (α = 5%). The epithelial remains of Malassez were present in the 3-day period and absent in other experimental times, in all the groups. In the 5-day period IOG shows thickness of the periodontal ligament and the percentage of fibrillar and non fibrillar extracellular matrix area significantly lower. On the 7th day IOG showed a significant reduction of the percentage of non fibrillar extracellular matrix area and clastic number of cells, and OTG shows the opposite. At 30 days the percentage of non-fibrillar extracellular matrix and the number of clastic cells was lower, and the number of cell profiles was higher in IOG. The traumatic occlusion significantly increases the number of clastic cells, while the absence of occlusal forces retards the onset and the number of them. Early occlusal load should be avoided in the teeth subjected to immediate replantation

Rescue of a periodontally compromised tooth by non-surgical treatment: a case report

PURPOSE: This article describes a case of the successful non-surgical management of a periodontally compromised maxillary premolar. METHODS: A combination therapy, including root planing, occlusal adjustment, and tooth splinting, was applied. Clinical and radiographic examinations were performed during the 16-month follow-up period. RESULTS: All periodontal parameters were improved. There were dramatic decreases (3–6 mm) in the probing pocket depth, tooth mobility, and marginal bone loss. Interestingly, gradual resolution of the periapical radiolucency and alveolar bone regeneration were observed in the radiographs, and the periodontal condition was maintained during the follow-up period. CONCLUSIONS: Within the limits of this study, these results demonstrate the importance of natural tooth preservation through proper periodontal treatment and occlusal adjustment of the periodontally compromised tooth, which is typically targeted for tooth extraction and dental implantation.

Wnt5a/Ror2 mediates temporomandibular joint subchondral bone remodeling.

Increased subchondral trabecular bone turnover due to imbalanced bone-resorbing and bone-forming activities is a hallmark of osteoarthritis (OA). Wnt5a/Ror2 signaling, which can derive from bone marrow stromal cells (BMSCs), takes a role in modulating osteoblast and osteoclast formation. We showed previously that experimentally unilateral anterior crossbites (UACs) elicited OA-like lesions in mice temporomandibular joints (TMJs), displaying as subchondral trabecular bone loss. Herein, we tested the role of BMSC-derived Wnt5a/Ror2 signaling in regulating osteoclast precursor migration and differentiation in this process. The data confirmed the decreased bone mass, increased tartrate-resistant acid phosphatase (TRAP)-positive cell number, and enhanced osteoclast activity in TMJ subchondral trabecular bone of UAC-treated rats. Interestingly, the osteoblast activity in the tissue of TMJ subchondral trabecular bone of these UAC-treated rats was also enhanced, displaying as upregulated expressions of osteoblast markers and increased proliferation, migration, and differentiation capabilities of the locally isolated BMSCs. These BMSCs showed an increased CXCL12 protein expression level and upregulated messenger RNA expressions of Rankl, Wnt5a, and Ror2. Ex vivo data showed that their capacities of inducing migration and differentiation of osteoclast precursors were enhanced, and these enhanced capabilities were restrained after blocking their Ror2 signaling using small interfering RNA (siRNA) assays. Reducing Ror2 expression in the BMSC cell line by siRNA or blocking the downstream signalings with specific inhibitors also demonstrated a suppression of the capacity of the BMSC cell line to promote Wnt5a-dependent migration (including SP600125 and cyclosporine A) and differentiation (cyclosporine A only) of osteoclast precursors. These findings support the idea that Wnt5a/Ror2 signaling in TMJ subchondral BMSCs enhanced by UAC promoted BMSCs to increase Cxcl12 and Rankl expression, in which JNK and/or Ca(2+)/NFAT pathways were involved and therefore were engaged in enhancing the migration and differentiation of osteoclast precursors, leading to increased osteoclast activity and an overall TMJ subchondral trabecular bone loss in the UAC-treated rats.

Cigarette smoke inhalation increases the alveolar bone loss caused by primary occlusal trauma in a rat model.

BACKGROUND AND OBJECTIVE: Occlusal trauma (OT) and smoking are both factors that alter alveolar bone metabolism and therefore could synergistically act on alveolar bone loss. The aim of this experimental study was to evaluate the influence of short-term cigarette smoke inhalation (CSI) on inter-radicular alveolar bone loss promoted by primary OT in a rat model. MATERIAL AND METHODS: Forty-eight animals were randomly assigned to one of three groups based on treatment type: OT + CSI (n = 16), animals were exposed to CSI three times per day, for 8 min per exposure, and they concomitantly received unilateral vertical augmentation creating an occlusal interference inducing experimental OT; OT (n = 16), animals received only unilateral vertical augmentation; negative control (NC; n = 16), animals maintained for equal periods to achieve periodontal baseline values of periodontal ligament dimension. Each group was divided into two subgroups (n = 8) based on treatment length: 7 or 14 d. RESULTS: After 7 d, the OT + CSI group exhibited significantly higher bone loss compared to the NC group (p = 0.0022). After 14 d, the OT (p < 0.0001) and OT + CSI (p < 0.0001) groups presented significantly higher bone loss compared to the NC group, and OT + CSI resulted in significantly higher bone loss than OT alone (p = 0.0241). The number of tartrate-resistant acid phosphatase-positive cells on the linear surface of the bone crest after 7 d was significantly higher in the OT + CSI group as compared to the NC and OT groups (p < 0.0001 and p = 0.0045, respectively) and remained significantly higher in the OT + CSI group after 14 d, compared to the OT group (p < 0.0001). CONCLUSION: Short-term CSI increases early bone loss in association with OT after 7 d, and this worsens in severity after 14 d of exposure.

Evolución de la patología oclusal: una revisión de literatura / Evolution of occlusal pathology: a literature review

Introducción: Muchos de los lineamientos sobre oclusión y de las alternativas de tratamiento en paciente dentado y parcialmente edéntulo, se basan en conceptos planteados en los inicios de la profesión. La diversidad de escuelas de oclusión ha hecho que, algunos de esos conceptos se tornen complejos para su entendimiento y aplicación. Esta diversidad hace que la compresión de la fisiología oclusal y sus alteraciones sea difícil, obstaculizando el entendimiento de la patología oclusal, su correcto diagnóstico y manejo. Objetivo: Es por esto que se realizó una revisión bibliográfica sobre fisiología y patología oclusal, con el propósito de recopilar información basada en la evidencia científica, que permitiera esclarecer conceptos y homogenizar el conocimiento acerca de los cambios en la fisiología y morfología del sistema estomatognático, asociados a las alteraciones oclusales, permitiendo a futuro la estandarización del proceso de diagnóstico oclusal en la Facultad de Odontología de La Universidad Nacional de Colombia. Metodología: Se realizó una búsqueda en bases de datos MedLine, PudMed, Ovid, Ebsco, ScienceDirect y Hinari- Healthinternetwork mediante los términos Mesh “Dental Occlusion”- “Stomatognathic System”- “Masticatory System” – Temporomandibular Joint y las palabras de texto libre pertinentes, así como las bibliografías de los trabajos y artículos de revisión que tuvieran relación directa con el tema; no se tuvo en cuenta la fecha de publicación. Resultados: Se obtuvo un total de 79 artículos, 10 textos y 7 páginas web. Conclusión: La patología oclusal es un proceso evolutivo que puede afectar cualquiera de los componentes del sistema estomatognático en su forma y/o función. La armonía oclusal es un estado en el que cada una de las partes del sistema funciona coordinadamente para cumplir las funciones de masticación, fonación y deglución; la rehabilitación oral debe encaminarse hacia la obtención de una oclusión armónica.

Introduction: Many of the guidelines on occlusion and treatment alternatives in dentate and partially edentulous patients, are based on concepts raised in the beginning of dentistry. The diversity of the occlusion schools has become some of these concepts complex to understand and apply. This diversity makes difficult the compression of the occlusal physiology and its disorders, hindering the understanding of the occlusal pathology and its proper diagnosis and management. Objective: This is why we conducted a literature review about oclusal physiology and pathology, in order to gather information based on scientific evidence, which in order to clarify concepts and homogenize knowledge about physiological and morphological changes of the stomatognathic system, associated to occlusal alterations, allowing the future standardization of the occlusal diagnostic process at the Faculty of Dentistry of the National University of Colombia. Methodology: A search was conducted in MedLine, PubMed, Ovid, Ebsco, ScienceDirect and Hinari-Healthinternetwork using the Mesh terms: "Dental Occlusion" - "Stomatognathic System" - "masticatory System" - Temporomandibular Joint and the bibliographies of papers and review articles that had direct relationship to the topic; the publication deadline was not taken into account. In total, 79 articles, 10 texts and 7 websites were obtained. Conclusion: Occlusal pathology is an evolutionary process that might affect the form and/or function of any of the components of the stomatognathic system. Occlusal Harmony is a state in which each part of the system works in concert with the others to fulfill the functions of mastication, speech and swallowing; oral rehabilitation should be directed toward obtaining a harmonious occlusion.

Equilíbrio oclusal no tratamento de injúria traumática secundária / Occlusal adjustment in the treatment of secondary traumatic injury

The success of the rehabilitation treatment is associated with the relationship between occlusion and periodontal status. When occlusal loads exceed the ability of the periodontium to resist and distribute the resulting forces, injuries may develop, leading to failures in dental practice. A 35-year-old female patient presented at the Occlusion and Orofacial Pain Research Center at the School of Dentistry, Universidade Federal de Goiás, Brazil, complaining of pain and mobility in the maxillary central incisors and sensitivity in the mandibular left incisors and canine. Symptoms began after cast metal restoration was performed in tooth #27. Clinical examination revealed a signifi cant difference of 1 mm between centric relation and habitual occlusion, presence of a periodontal pocket 5 mm deep in the mesial aspect of tooth #11, and an increased vertical dimension of occlusion caused by occlusal interference between teeth #27 and #37. Radiographic examination detected vertical bone loss between teeth #21 and #11, on the mesial aspect of tooth #33 and between the lower incisors. The lower teeth also showed radiographic evidence of periapical lesions. Occlusal interference caused anterior projection of the mandible to the right, overloading the incisors. Treatment by occlusal adjustment was performed to promote an equal incidence of forces on all aspects of the teeth. Twelve sessions were required to achieve a balanced occlusion and restore the physiological vertical dimension of occlusion. Six months after treatment, there was radiographic evidence of newly formed bone tissue between teeth #11 and #21, regression of apical periodontitis in the lower teeth, and a decrease in mobility and all associated symptoms. Secondary traumatic injury may be responsible for changes in apical tooth structures. Occlusal adjustment may favor the direction of occlusal forces to the long axis of the teeth.

O sucesso do tratamento reabilitador associa-se à relação entre a oclusão e a periodontia. Quando cargas oclusais excedem a capacidade periodontal de suportar e distribuir as forças resultantes, podem ocorrer traumas,os quais seriam responsáveis por fracassos na prática odontológica. Uma paciente de 35 anos compareceu ao Centro de Pesquisa em Oclusão e Dor Orofacial da Faculdade de Odontologia, Universidade Federal de Goiás, Brasil, com queixa de dor e mobilidade nos incisivos centrais superiores e sensibilidade nos dentes incisivo e canino esquerdos inferiores. A sintomatologia teve início após a confecção de uma restauração metálica fundida no dente 27. Ao exame clínico, observou-se diferença significativa de 1 mm entre a relação central e a oclusão habitual, presença de bolsa periodontal de 5 mm na face mesial do dente 11 e aumento da dimensão vertical de oclusão provocada por interferência oclusal entre os dentes 27 e 37. O exame radiográfi co detectou perda óssea vertical entre os dentes 21 e 11, na face mesial do dente 33 e entre os incisivos inferiores. Os dentes inferiores também apresentavam lesão radiolúcida indicativa de periapicopatia. O contato interferente provocava projeção mandibular anterior e para a direita, promovendo sobrecarga nos incisivos. O tratamento por ajuste oclusal foi indicado para promover igualdade de incidência de forças em todos os elementos dentários. Foram necessárias 12 sessões para obtenção de uma oclusão equilibrada e resgate da dimensão vertical de oclusão fisiológica. Seis meses após o tratamento, observou-se ao exame radiográfico neoformação óssea entre os dentes 11 e 21, regressão da periapicopatia nos dentes inferiores e redução da mobilidade e de toda sintomatologia associada. A lesão traumática secundária pode ser responsável por alterações nas estruturas apicais dos dentes. O ajuste oclusal pode favorecer o direcionamento das forças oclusais para o eixo longo dos elementos dentários.

Equilíbrio oclusal no tratamento de injúria traumática primária / Occlusal adjustment in the treatment of primary traumatic injury

A major concern in dentistry is the correct distribution of occlusal forces to promote balance among the elements of the stomatognathic system. Occlusal trauma may develop in situations where the magnitude of the load exerted by occlusion exceeds the ability of the periodontium surrounding the involved teeth to resist and distribute the resulting forces without moving. A 41-year-old female patient was referred to the Occlusion and Orofacial Pain Research Center at the School of Dentistry, Universidade Federal de Goiás, Brazil, with headache, temporomandibular joint pain, toothache, and bone resorption on the distal aspect of tooth #33. During clinical examination, a 2-mm difference between centric relation and habitual occlusion was detected, with interference between teeth #28 and #38, causing anterior projection of the mandible to the right. Probing depth of the lower canine was within normal limits, with a positive pulp vitality test. We concluded that pain and (grade II) mobility in tooth #33 were caused by interference of third molars, which exerted a distal pressure on the lower canine, characterizing primary occlusal trauma. Occlusal adjustment by selective grinding was then indicated to eliminate premature contact. Ten sessions were required to obtain optimal occlusion. Three months after treatment, follow-up radiograph showed newly formed bone tissue between teeth #33 and #34, with absence of mobility and symptoms. The case reported here indicates that occlusal adjustment is recommended for the treatment of periodontal injuries caused by traumatic occlusion. The treatment allows the achievement of an optimal occlusion by directing occlusal forces to the long axis of the teeth.

Uma das principais preocupações na odontologia é a distribuição correta das forças oclusais para que haja equilíbrio entre os elementos do complexo estomatognático. O trauma oclusal pode ocorrer quando a magnitude da carga exercida pela oclusão excede a capacidade do tecido periodontal ao redor dos elementos dentários envolvidos de resistir e distribuir as forças resultantes sem se mover. Uma paciente de 41 anos foi encaminhada ao Centro de Pesquisa em Oclusão e Dor Orofacial da Faculdade de Odontologia, Universidade Federal de Goiás, Brasil, com quadro clínico de cefaleia, dor nas articulações temporomandibulares, dor de dente e reabsorção óssea na face distal do dente 33. Ao exame clínico, detectou-se 2 mm de diferença entre a relação central e a oclusão habitual, com interferência entre os dentes 28 e 38, causando projeção mandibular anterior e para a direita. A profundidade de sondagem do canino inferior encontrava-se dentro dos limites normais, respondendo positivamente ao teste de vitalidade pulpar. Concluiu-se que a dor e a mobilidade (grau II) no dente 33 foram causadas por interferência existente entre os terceiros molares, fazendo com que o canino inferior fosse pressionado distalmente, caracterizando trauma oclusal primário. Para eliminar o contato prematuro, o tratamento indicado foi o ajuste oclusal por desgaste seletivo. Foram necessárias dez sessões para a obtenção de uma oclusão equilibrada. Após três meses de acompanhamento verificou-se ao exame radiográfico neoformação óssea entre os dentes 33 e 34, com desaparecimento da mobilidade e dos sintomas. O caso aqui relatado indica que o ajuste oclusal é recomendado para o tratamento de injúria periodontal causada por trauma oclusal. O tratamento permite atingir ótima oclusão ao direcionar as forças oclusais para o eixo longo dos elementos dentários.