Root filled teeth in two parallel Danish cohorts: A repeated longitudinal cohort study.

Area of Science:

• Endodontics
• Dental Public Health
• Radiodontics

Background:

• Root-filled teeth (RFs) are common in dental practice.
• Assessing the long-term outcomes and associated factors of RFs is crucial for clinical decision-making.
• Longitudinal data on RF quality and periapical status are essential for understanding treatment success.

Purpose of the Study:

• To compare the frequency and quality of root fillings (RFs) between two Danish cohorts over a 10-year period.
• To evaluate factors associated with apical periodontitis (AP) and extraction of root-filled teeth.

Main Methods:

• Two Danish cohorts (C1, C2) were followed for approximately 10 years with radiographic surveys at 5-year intervals.
• Data on RF frequency, quality, coronal restorations, periapical status, and tooth extractions were collected.
• Logistic regression analyses were used to compare cohorts and identify associated factors.

Main Results:

• The relative frequency of root-filled teeth and new RFs was lower in C2 compared to C1 over the study period.
• The quality of new RFs and coronal restorations was similar between the cohorts.
• Tooth extraction and apical periodontitis (AP) risks at 10-year follow-up were similar between cohorts.
• Root-filled molars and teeth with baseline AP showed increased risks of AP and extraction.
• Inadequate RF or coronal restoration quality was associated with increased AP risk.

Conclusions:

• The frequency of root-filled teeth and new RFs declined over time, with stable quality and outcomes.
• Root-filled molars and teeth with pre-existing apical periodontitis are at higher risk for adverse outcomes.
• Inadequate root filling or coronal restoration quality increases the risk of apical periodontitis.