ABSTRACT
We aimed to assess the relationship between age, pulpal blood flow (PBF), and orthodontic treatment outcomes. Decreased blood supply to pulp cells commonly occurs with age and can change the response of pulp to orthodontic tooth movement. This study was conducted in 28 human subjects divided into 2 groups according to age. A laser Doppler flowmeter was used to record blood flow to the teeth prior to and during the course of orthodontic treatment (days 1, 3, and 7; week 3; and month 1). Data were analyzed using Wilcoxon signed-rank and Mann-Whitney U tests. Mean PBF values were significantly higher in the young group compared to the old group at all time points (P < 0.001). The decreased PBF in response to tooth movement was more severe in the old group and was also of longer duration. Pulp in younger patients had significantly higher blood flow values compared to that in older patients at baseline and throughout the course of the study.
Subject(s)
Dental Pulp/blood supply , Tooth Movement Techniques , Adolescent , Adult , Age Factors , Female , Humans , Laser-Doppler Flowmetry , Male , Middle Aged , Treatment OutcomeABSTRACT
INTRODUCTION: In this study, we aimed to evaluate and compare blood-flow changes in the pulp tissues of maxillary molars over a 6-month period after orthodontic intrusion using different magnitudes of force. METHODS: Twenty patients were randomly divided into 2 groups (n = 10) according to the amount of intrusive force applied. An intrusive force of either 125 g (light) or 250 g (heavy) was applied to the overerupted maxillary first molars using mini-implants; no force was applied to the contralateral molars. Laser Doppler flowmetry was used to measure pulpal blood flow (PBF) at baseline and during intrusion at 24 hours, 3 days, 7 days, 3 weeks, 4 weeks, 3 months, and 6 months. The data were analyzed with the Mann-Whitney U and Wilcoxon signed rank tests, with P <0.05 considered statistically significant. RESULTS: PBF decreased significantly at 3 days and continued to remain suppressed until 3 weeks, after which a gradual trend of recovery was observed until 3 months, when the levels returned to near those measured before intrusion. When the data were analyzed with regard to the amount of applied force, significant differences were observed between the 2 groups only at 3 and 7 days. CONCLUSIONS: These findings demonstrate that despite slight regressive changes in pulpal tissue over the short term, PBF values tend to return to their initial levels within 3 months, indicating that changes observed in PBF are reversible, even during radical intrusions of molars with 125 and 250 g of forces.
