A retrospective study of isolated fractures of the alveolar process in the permanent dentition

There is a lack of studies of fractures of the alveolar process (FAP). Only five were published in the last 50 years. The aim of this study was to analyze the risk of pulp necrosis and infection (PN), pulp canal obliteration (PCO), infection-related root resorption (IRR), ankylosis-related resorption (ARR), marginal bone loss (MBL), and tooth loss (TL) as well as to identify the possible risk factors for teeth involved in an isolated alveolar process fracture. In the second part, any late complications of the involved teeth were reported in patients who responded to a follow-up examination.

This study was a retrospective analysis of 126 patients with 329 traumatized permanent teeth treated in a regional dental trauma clinic. Follow-up examination was performed on 31 (24.6%) patients with 75 (22.8%) teeth. The risks of PN, PCO, RR, MBL, and TL were analyzed using the Kaplan-Meier method. Possible risk factors for PN (stage of root development, fracture position in relation to the root apex, concomitant injury, treatment delay, and antibiotics) were analyzed using univariate and multivariate Cox regression and generalized estimating equation. The level of significance was 5%.

Pulp necrosis was observed in 43% of the teeth, and it was significantly associated with the presence of a concomitant injury and complete root formation. PCO was recorded in 2.8%, root resorption (RR, IRR, and ARR) in 4%, MBL in 8%, and TL in 0.6% of the teeth. Thirty-four percent of the teeth were assumed to have normal pulps, but they did not respond to pulp sensibility testing. At the follow-up examination, PN was found in 49%, PCO in 28%, RR (IRR and ARR) in 4%, MBL in 17%, and TL in 5%. Estimated risk after a 5-years follow up was as follows: PN: 48.2% (95% confidence interval (CI): 42.0-54.5), IRR: 7.2 (95% CI: 3.5-10.9), ARR: 33.0% (95% CI: 22.4-43.6), BL: 16.7% (95% CI: 9.6-23.8), TL: 4.0% (95% CI: 0.0-8.5). The following factors significantly increased the risk of PN: mature root development (hazard ratio [HR]: 7.50 [95% CI: 1.84-30.64], P=.005) and concomitant injury (HR: 2.68 [95% CI: 1.76-4.09], P<.001). In a logistic regression model, teeth with mature roots had a threefold risk of becoming non-responsive to pulp testing.

Teeth involved in an isolated alveolar process fracture and managed with a conservative treatment approach appear to have a good prognosis. The most common complication was PN which did not negatively affect the survival of the teeth after root canal treatment.