Evaluation of occlusion and disocclusion time in immediately loaded implant overdentures retained by two splinted versus non-splinted interforaminal implants: A randomized clinical trial
摘要
Mandibular complete dentures often lack stability, leading to prolonged occlusion and disocclusion times. Immediate-loading implant overdentures can improve functional control, but evidence comparing splinted and non-splinted two-implant overdentures is limited. This randomized clinical trial aimed to evaluate occlusion and disocclusion times in patients receiving immediately loaded mandibular overdentures retained by two implants, comparing ball attachments and intraoral welded bar attachments, with conventional complete dentures serving as the control group.
MethodsThirty-six completely edentulous patients were randomized into three equal groups (n = 12 each): conventional complete dentures (CD), two-implant overdentures retained with ball attachments (IB), and two-implant overdentures retained with an intraoral welded bar (IW). Occlusion (OT) and right and left disocclusion times (DR, DL) were measured using the T-Scan system on the day of implant placement (T1) and after three months (T2). Data were normally distributed; Mixed ANOVA was used to assess the effects of time, treatment, and their interaction. Paired t-tests were additionally used for within-group comparisons. Post hoc Tukey tests were performed for pairwise comparisons, with Bonferroni correction applied for multiple testing. Statistical significance was set at P < 0.05.
ResultsAt T1, the CD group exhibited significantly longer occlusion time (OT: 0.52 ± 0.07 s), right disocclusion time (DR: 0.57 ± 0.04 s), and left disocclusion time (DL: 0.58 ± 0.04 s) compared with the IB (OT: 0.35 ± 0.06 s; DR: 0.40 ± 0.04 s; DL: 0.40 ± 0.02 s) and IW (OT: 0.29 ± 0.02 s; DR: 0.36 ± 0.03 s; DL: 0.42 ± 0.01 s) groups (P < 0.001), indicating that implant-supported overdentures achieved more efficient occlusal contacts. No significant differences were observed between IB and IW. At T2, the pattern persisted, with the CD group showing a significant reduction in OT, DR, and DL over time (P < 0.05), reflecting improved OT and DT of CD, whereas both implant overdenture groups maintained stable OT and DT.
ConclusionsWithin three months of follow-up, immediately loaded mandibular overdentures retained by two implants showed similar OT and DT for IW and IB, while both groups showed shorter times compared to CD under the tested conditions.
Trial registrationThis randomized clinical trial was registered prospectively on Clinical Trials.gov with the Identification number: NCT06376019 on 19/04/2024.