Healing and long-term prognosis of root-fractured permanent teeth: a retrospective longitudinal study.

AIM: The purpose of the present study was to evaluate permanent teeth with post-traumatic transversal root fractures, for their initial healing modality, the effect of candidate predictors and their long-term prognosis. METHODOLOGY: A retrospective longitudinal clinical study was conducted to evaluate records from patients bearing transversal root fractures in permanent teeth in order to radiographically assess short-term healing and non-healing events in the fracture line, their prognostic factors and their relationship with long term outcomes. The inter-fragmentary tissues were classified as healing: hard tissue (HT), connective tissue (CT) or connective tissue and bone (CT + B) and non-healing: interposition of granulation tissue (GT). A competing risk survival analysis was conducted to estimate the hazards of healing and non-healing events in the short-term and the effect of demographic, clinical, and treatment variables was assessed using the subdistribution regression model (Fine & Gray). RESULTS: Radiographic findings showed 61.4% of healing in the short-term being strongly influenced by the presence and type of concomitant injuries to the coronal fragment. Teeth with concomitant crown fractures (sHR 24.38, 95% CI [3.16-188.3], p = 0.0022), luxations with dislocations (sHR 10.58, 95% CI [1.37-81.9], p = 0.0240) and subluxations (HR 9.66, 95% CI [1.14-81.7], p = 0.0370) were more likely to present non-healing of root fractures in the short-term. The healing rate in the long-term was of 75.9%, most of them with interposition of bone and connective tissue. Kappa statistics demonstrated an overall agreement of 67.1% between short and long-term healing patterns, in special HT and CT + Bone modalities. CONCLUSION: Healing at the fracture site was the most frequent outcome, both in the short-term and in the long-term. Short-term healing modality was strongly influenced by the presence and type of concomitant injuries to the crown fragment, being the worst prognosis observed in root-fractured teeth with concomitant crown fractures, followed by concomitant luxations with dislocation. CLINICAL RELEVANCE: Post-traumatic transversal root fractures have a positive prognosis supporting therefore, a more conservative approach for these teeth before considering more radical treatments.

Cicatrização e prognóstico no longo prazo de fraturas radiculares transversais pós-traumáticas: estudo clínico longitudinal / Healing and long-term prognosis of root fractured permanent teeth: a retrospective longitudinal study

Fraturas radiculares são lesões traumáticas dento-alveiolares (LTDA) complexas que afetam dentina, cemento, polpa e o ligamento periodontal, sendo frequente a ocorrência de lesões concomitantes ao fragmento coronário. São lesões relativamente raras com frequências relatadas variando entre 1,2% e 7% das LTDA na dentição permanente, sendo mais comuns em dentes com completo desenvolvimento radicular. O presente estudo consistiu em um levantamento clínico longitudinal retrospectivo para avaliar dados de 87 pacientes, portadores de 104 dentes permanentes com fraturas radiculares transversais, atendidos na Clínica de Traumatismos Dentários da Faculdade de Odontologia da UFMG, durante o período de 1995 a 2022. Com base na análise dos prontuários, avaliou-se o padrão radiográfico de cicatrização na linha de fratura, seguindo os critérios estabelecidos por Andreasen e Hjorting-Hansen (1967), em dois momentos: no período inicial após o trauma e ao final do período de acompanhamento. Uma análise de sobrevivência de risco competitivo foi realizada para estimar as taxas dos eventos de cicatrização no período inicial após o trauma, bem como o efeito das variáveis demográficas, clínicas e relacionadas ao tratamento. Os resultados demonstraram um percentual de 51,9% de cicatrização no curto prazo, diagnosticada em até 5 meses após o trauma. A não cicatrização com interposição de tecido de granulação na linha de fratura foi fortemente influenciada pela presença e tipo de lesão concomitante no fragmento coronário. Dentes com fraturas de esmalte e dentina (sHR 24,38, IC 95% [3,16 - 188,3], p = 0,0022), luxações com deslocamentos (sHR 10,58, IC 95% [1,37 - 81,9], p = 0,0240) e subluxações (HR 9,66, IC 95% [1,14 - 81,7], p = 0,0370) apresentaram as maiores taxas de não cicatrização das fraturas radiculares no curto prazo. A taxa de cicatrização no longo prazo foi de 70,1%, a maioria delas com interposição de osso e tecido conjuntivo. A estatística Kappa demonstrou uma concordância global de 67,1% entre as modalidades de cicatrização no período inicial e no longo prazo, especialmente para os padrões tecido mineralizado e tecido conjuntivo/osso.

Root fractures are complex traumatic dental injuries (TDI) affecting dentin, cementum, pulp and supporting tissues, generally associated to concurrent injuries to the coronal fragment. They are uncommon injuries with reported frequencies varying between 1.2% and 7% of all TDI in permanent teeth, being more frequent in teeth with complete root development. In the present study we retrospectively evaluated data from 87 patients with104 root-fractured permanent teeth treated at the Dental Trauma Clinic from the Federal University of Minas Gerais, during the period from 1995 to 2022. Clinical dan radiographic data was collected from patient's records to establish healing patterns in the fracture line, following the criteria established by Andreasen & Hjorting-Hansen (1967), at two moments: in the initial period after the trauma and at the end of the follow-up period. A competing risk survival analysis was performed to estimate rates of healing events in the early period after trauma as well as the effect of demographic, clinical, and treatment-related variables. The results showed a rate of 51.9% of healing in the short term, diagnosed in a maximum median period of 5 months after trauma. Non-healing with interposition of granulation tissue at the fracture line was strongly influenced by the presence and type of concomitant lesion in the coronal fragment. Teeth with associated enamel -dentin fractures (sHR 24.38, 95% CI [3.16 - 188.3], p = 0.0022), luxations with dislocations (sHR 10.58, 95% CI [1.37 - 81.9], p = 0.0240) and subluxations (HR 9.66, 95% CI [1.14 - 81.7], p = 0.0370) had the highest rates of non-healing of root fractures in the short term. The long-term healing rate was 70.1%, most of them with interposition of bone and connective tissue. Kappa statistics demonstrated an overall agreement of 67.1% between short and long-term healing patterns, in special HT and CT+ Bone modalities.