A retrospective cohort study of pulp prognosis in luxated permanent teeth: a competing risk analysis.

AIM: The present retrospective cohort study aimed to evaluate luxated permanent teeth for pulp prognosis and risk factors. METHODOLOGY: Case records and radiographs of 224 patients, involving 427 luxated permanent teeth, referred for treatment at the Dental Trauma Center-School of Dentistry, Universidade Federal de Minas Gerais, (DTC-SD-UFMG) from 2014 to 2022, were assessed for pulp prognosis classified as vitality, necrosis and pulp canal obliteration (PCO). A competing risk survival analysis estimated the hazards of the three outcomes, and the effect of demographic, clinical and treatment variables was tested using a cause specific Cox regression model. RESULTS: Pulp vitality was found in163 teeth (38.2%), pulp necrosis in 120 teeth (28.1%) and 55 teeth (12.9%) developed PCO. Pulp vitality decreased in the presence of concomitant crown fractures (HR 0.38 95% CI [0.2-0.8] p = 0.006). The risk of pulp necrosis (HR 0.62 95% CI [0.4-0.96] p = 0.03) was lower in cases with open apices but increased with concomitant crown fractures (HR 4.0 95% CI [2.6-6.1] p = 0.001) and intrusions (HR 2.3 95% CI [1.2-4.1] p = 0.007). Lateral or extrusive luxations (HR 3.0 95% CI [1.3-6.9] p = 0.001) and open apices (HR 2.4 95% CI [1.2-4.7] p = 0.01) showed higher rates of PCO. CONCLUSION: Type of luxation, the diameter of the apical foramen, and the presence of concomitant crown fractures were main determinants of pulp prognosis after luxation injuries in permanent teeth. CLINICAL RELEVANCE: Pulp prognosis after tooth luxation is dependent on the presence and direction of tooth displacement together with infection control. CLINICAL TRIAL REGISTRATION: Not applicable.

Pulp healing in immature replanted permanent teeth: A competing risk analysis.

BACKGROUND/AIM: Tooth displacement during avulsion causes total rupture of the pulp's neurovascular supply. Revascularization and pulp healing may occur in immature teeth, which gives rise to the recommendation that root canal treatment may not be required. The aim of this study was to evaluate the prognostic factors for the pulp's response after replantation of young permanent teeth. METHODS: Records from 117 patients with 133 replanted permanent immature teeth were reviewed, and pulp outcomes were classified as healing (hard tissue deposition on the dentinal walls followed by narrowing of the pulp lumen or ingrowth of bone-like tissue inside the pulp canal) or non-healing (pulp necrosis with infection). The effect of clinical and demographic co-variates on the hazards of both outcomes was assessed performing a competing risk model. RESULTS: Pulp necrosis with infection was diagnosed in 78.2% of the teeth, and healing was observed in 12.8% of the teeth. A total of 12 teeth (9.0%) were censored due to prophylactic removal of the pulp or severe external root resorption caused by eruption of adjacent canines. The cs-Cox model demonstrated that the hazards of pulp healing increased in teeth with extra-alveolar periods <15 min (csHR: 7.83, 95% CI 1.76-34.80, p = .01), while the hazards of pulp necrosis with infection decreased (csHR: 0.31, 95% CI: 0.10-0.92, p = .04). Teeth replanted with Moorrees' stages 4 and 5 of root development had higher hazards of pulp necrosis with infection than teeth with stage 2 of root development (csHR: 2.23, 95% CI 1.11-4.50, p = .03; csHR: 2.89, 95% CI: 1.40-5.95; p = .01). CONCLUSIONS: Pulp healing rarely occurred after replantation of young permanent teeth being associated with short extra-alveolar periods <15 min. Early stages of root development decreased the hazards of pulp necrosis with infection.

Prevalence of traumatic dental injuries in emergency dental services: A systematic review and meta-analysis.

OBJECTIVES: This study aimed to perform a systematic review and meta-analysis regarding the prevalence of traumatic dental injuries (TDI) in emergency dental services. METHODS: Seven electronic and two grey literature databases were searched, up to December 2021, for studies that reported the TDI prevalence among dental emergencies. The Joanna Briggs Institute critical appraisal checklist for prevalence studies, and The Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach were used to assess the risk of bias and quality of evidence respectively. The R software was used to perform a proportion meta-analysis on a random-effects model to estimate the pooled prevalence and respective 95% CI. RESULTS: From a total of 1476 studies identified after excluding duplicates, 38 met the inclusion criteria, and another five were identified through hand searching, summing 43 included observational studies with a total sample of 209099 individuals searching for emergency dental care. The overall pooled prevalence of TDI was 15.4% (95% CI: 11%-21%, I² = 100%). Paediatric dental emergency services and age group from 0 to 21 years presented the highest prevalence, 29% (95% CI: 22%-38%, I² = 99.5%) and 24% (95% CI: 15%-35%, I² = 98%) respectively. CONCLUSIONS: The overall pooled prevalence of TDI in emergency dental services was 15.4%, and 24% in the age group under 21 years. Considering the impact of prompt and correct emergency care in the long-term prognosis of TDI, such knowledge is relevant to organize emergency healthcare and support public policies in this area.

Expression of matrix metalloproteinases 2 and 9 in replanted teeth with external root resorption: A cross-sectional study.

OBJECTIVE: To evaluate matrix metalloproteinase (MMP) expression in replanted permanent teeth with external root resorption (ERR). DESIGN: The present cross-sectional study included 42 patients with replanted permanent teeth, presenting with progressive forms of ERR, and referred for extraction according to the rehabilitation treatment plan or due to root fractures. The control group consisted of 12 healthy premolars, from 5 patients with good periodontal health and no radiographic evidence of root resorption, referred for extraction for orthodontic reasons. Root fragments were processed soon after extraction, and the supernatant was collected to measure matrix metalloproteinase 2/tissue inhibitor of metalloproteinase 2 (MMP-2/TIMP-2) and matrix metalloproteinase 9/tissue inhibitor of metalloproteinases 2 (MMP-9/TIMP-2) complexes through a double-ligand enzyme-linked immunosorbent assay (ELISA). RESULTS: Case groups with external inflammatory root resorption (EIRR) or external replacement root resorption (ERRR) showed significantly higher levels of MMP-2/TIMP-2 and MMP-9/TIMP-2 complexes than the control group. Additionally, comparisons between the case groups demonstrated that the MMP-2/TIMP-2 complex also had significantly higher levels in the ERRR group (p < 0.001). CONCLUSIONS: Our results suggest that MMP-2 and MMP-9 participate in the pathobiology of both types of ERR. In addition, the higher levels of MMP-2/TIMP-2 complex in the ERRR group support common modulation mechanisms with physiological bone turnover.