Prognóstico pulpar após lesões por luxação em dentes permanentes: uma análise de riscos competitivos / A retrospective cohort study of pulp prognosis in luxated permanent teeth: a competing risk analysis

As lesões por luxação representam o grupo de lesões traumáticas dento-alveolares (LTDA) caracterizadas pelo dano simultâneo ao feixe vásculo-nervoso periapical e estruturas de sustentação dentária, em diferentes graus de complexidade, dependendo da força e direção do impacto. A patogenia das alterações pulpares decorrentes das luxações é resultado da extensão da lesão do feixe vásculo-nervoso apical e de sua capacidade de reparo, que determinam os seguintes desfechos para a polpa: manutenção da vitalidade pulpar, manutenção da vitalidade pulpar com obliteração da cavidade pulpar (OCP) ou a necrose pulpar. Entretanto, o processo de reparo pulpar pode envolver fenômenos intermediários cujos sinais e sintomas se modificam ao longo do período de acompanhamento até um diagnóstico definitivo. Sendo assim, do ponto de vista clinico, o tempo até a observação destas respostas, bem como seus fatores determinantes, representa uma informação tão importante quanto o próprio desfecho, pois tem influência direta na tomada de decisão sobre as condutas clinicas mais adequadas. A presente pesquisa consistiu num estudo clínico longitudinal retrospectivo com o objetivo de avaliar o prognóstico pulpar de dentes permanentes portadores de lesões por luxação, seu padrão cronológico e fatores determinantes, entre os pacientes atendidos na Clínica de Traumatismos Dentários da Faculdade de Odontologia da Universidade Federal de Minas Gerais no período de 2014 a 2022. Foram analisados prontuários de 224 pacientes com 427 dentes permanentes portadores de luxações, acompanhados por um período mediano de 1,4 anos (variação de 11 dias a 6,9 anos). O padrão de resposta pulpar foi classificado como manutenção da vitalidade pulpar, OCP e necrose pulpar através da avaliação clínica e radiográfica. Uma análise de sobrevivência utilizando-se o modelo de riscos competitivos foi realizada e curvas de função de incidência acumulada (FIA) foram construídas para se avaliar as taxas de cada um dos desfechos pulpares utilizando-se o estimador de Aalen-Johansen. O efeito de variáveis independentes, incluindo sexo, idade do paciente no momento do trauma, estágio de desenvolvimento radicular, grupo dentário, tipo de luxação, presença de fratura coronária concomitante e prescrição de antibioticoterapia sistêmica (ATS), foi avaliado utilizando-se um modelo multivariado de Cox causa-específico. Os dados foram analisados no programa estatístico R (versão 4.0.4, Viena, Áustria, 2021). Os resultados demonstraram manutenção da vitalidade pulpar em 38,2% da amostra (163 dentes), necrose pulpar em 28,1% (120 dentes) e OCP em 12,9% da amostra (55 dentes). O tempo mediano para o diagnóstico de necrose pulpar foi de 3 meses, enquanto o tempo para vitalidade pulpar foi de 8 meses e para OCP foi de 16 meses A probabilidade de manutenção de vitalidade pulpar diminuiu significativamente com a ocorrência de fraturas coronárias de esmalte e dentina concomitantes (HR 0,38 IC 95% [0,2 ­ 0,8] p = 0,006). A taxa de necrose pulpar foi significativamente menor em dentes com forame apical amplo (HR 0,62 IC 95% [0,4 ­ 0,96] p = 0,03) mas aumentou significativamente em dentes com luxações associadas às fraturas coronárias (HR 4,0 IC 95% [2,6 - 6,1] p = 0,001) e em dentes portadores de luxações intrusivas (HR 2,3 IC 95% [1,2 - 4,1] p = 0,007). Dentes portadores de luxações laterais ou extrusivas (HR 3,0 IC 95% [1,3 ­ 6,9] p = 0,001) ou com forame amplo (HR 2,4 IC 95% [1,2 ­ 4,7] p=0.01) apresentaram as maiores taxas de OCP.

Luxation injuries are a group of traumatic dental injuries (TDI) that involve damage to both the pulp and periodontium, with different degrees of complexity. Pulp damage results from injury to the apical neuro-vascular bundle and, depending on the repair potential, may result in the following outcomes: maintenance of pulp vitality, maintenance of pulp vitality with pulp canal obliteration (PCO) or pulp necrosis. However, the pulp healing process may involve intermediate and reversible phenomena whose signs and symptoms mimic pulp necrosis, rendering the timing of these events critical for decision-making during the follow-up period. The present study consisted in a retrospective cohort to evaluate the pulpal prognosis of luxated permanent teeth, its chronological pattern and predictive factors, among patients treated at the Dental Trauma Clinic of the Federal University of Minas Gerais, from 2014 to 2021. Records of 224 patients with 427 permanent teeth with luxations, followed up for a median period of 1.4 years (ranging from 11 days to 6.9 years) were analysed. Pulp outcomes - maintenance of pulp vitality, PCO and pulp necrosis were defined trough clinical and radiographic evaluation. A competing risk survival analysis was performed and cumulative incidence function (CIF) curves were build using the Aalen-Johansen estimator to assess the rates of each of the pulp outcomes during the follow-up period. The effect of independent variables including patient's gender and age at the time of trauma, tooth group and stage of root development, type of luxation, concomitant injuries, systemic antibiotic therapy (SAT) prescription, was evaluated using a cause-specific Cox regression model. Data were analysed in the R statistical program (version 4.0.4, Vienna, Austria, 2021). The results showed maintenance of pulp vitality in 38.2% of the sample (163 teeth), pulp necrosis in 28.1% (120 teeth) and OCP in 12.9% of the sample (55 teeth). The median time for the diagnosis of pulp necrosis was 3 months, while the time for pulp vitality was 8 months and for PCO was 16 months. The hazards of pulp vitality significantly decreased with the occurrence of concomitant coronal fractures (HR 0 .38 95% CI [0.2 ­ 0.8] p = 0.006). The hazards of pulp necrosis was significantly lower in teeth with a wide apical foramen (HR 0.62 95% CI [0.4 ­ 0.96] p = 0.03) but increased significantly in teeth with luxations associated with crown fractures (HR 4.0 CI 95% [2.6 - 6.1] p = 0.001) and in teeth with intrusive displacement (HR 2.3 CI 95% [1.2 - 4.1] p = 0.007). Teeth with lateral or extrusive luxations (HR 3.0 CI 95% [1.3 ­ 6.9] p = 0.001) or with a wide foramen (HR 2.4 CI 95% [1.2 ­ 4.7] p =0.01) showed the highest rates of PCO.

Factors Affecting the Pulp and Root Healing of Root Fractures in Immature Permanent Teeth / 대한소아치과학회지

The aim of this study was to evaluate the factors affecting the healing of root fracture in immature permanent teeth and the prognosis of root fracture by statistically analyzing the relationship with the pulp and root healing.The radiographs of 51 root-fractured maxillary anterior permanent teeth were collected. In radiograph, locations of root fracture, apical foramen width and width of diastasis between the fragments were measured. The value of the studied parameters were compared by independent t-test and rogistic regression test.In conclusion, there was no difference in the prognosis of pulp healing according to the location of root fracture. However, root healing occurs well as the root fracture is located at the root apex (p < 0.05). Lastly, the smaller the width of diastasis between the fragments after reduction, the better the pulp healing was (p < 0.05).

Histology of dental pulp healing after tooth replantation in rats / 대한치과보존학회지

The objective of this study was to observe the histology of dental pulp healing after tooth replantation in rats. The maxillary right first molars of 4-week-old rat were extracted, and then the teeth were repositioned in the original socket. At 3 days after replantation, there was localized inflammatory reaction. But, pulp revasculization and healing had already begun in the root area. At 5 days after replantation, odontoblast-like cells were observed. Tertiary dentin deposition was observed beneath the pulp-dentin border from 1 week after replantation. And tertiary dentin was increased at 2 weeks after replantation. The presence of odontoblast-like cells and the formation of tertiary dentin were continued to 4 weeks after replantation. At 4 weeks after replantation, the deposition of bone-like tissues and cementum-like tissues was observed. This results show that there is a possibility of pulp healing after tooth replantation in rats and the mineralization of tooth can progress. The mineralization of tooth after replantation was initially occurred by the deposition of tertiary dentin, but as time passed, the deposition of bone-like tissues and cementum-like tissues was begun and increased.

Autotransplantation of immature third molars; Pulp healing, periodontal healing and root development

PURPOSES: The aim of this study was to evaluate pulp healing, periodontal healing, root development of autotransplantation of immature third molars and show its viability in treatment of early loss of tooth in young patients MATERIALS AND METHODS: In this article we performed a retrospective study with 41 transplanted teeth in 36 patients. The Mean age at the time of surgery was 17 years(range 13-24 years) and mean postoperative follow up period was 2.4 years(range 1-6 years) We evaluated the survival rate, pulp healing, periodontal healing, root development of the above teeth RESULTS: At the last examination 40 teeth among 41 transplants were still present so survival rate was 97.6%. The pulpal healing was found in 38 teeth of 41 transplants. The periodontal healing was found in 38 transplants. The continuous root development was seen in 38 transplants. CONCLUSIONS: From the above results, the autotransplantation of immature third molars was found to be a useful and reliable treatment method for early loss of teeth in adolescents and young adults.