Closed sinus lift and fixed prostheses versus implant-assisted overdentures in management of atrophied distal extension maxillary ridges: A one-year randomized clinical trial

Abstract

Rehabilitation of elderly or medically compromised patients with an atrophied unilateral posterior maxillary ridge by an implant-supported prosthesis may be complicated by maxillary sinus pneumatization with insufficient bone for implant placement. This short-term clinical trial assessed clinical results of closed sinus lift and fixed prosthesis versus implant-assisted overdentures in the management of participants with atrophied distal extension maxillary ridges. Forty participants with unilateral atrophying distal extension maxillary ridges were randomly assigned into 2 groups. The CSL group (n=20) participants received fixed prostheses supported by 3 implants following a closed sinus lift. The IOD group (n=20) participants received removable partial overdentures assisted by a single implant that was positioned mesially to the maxillary sinus. The modified plaque index (MPI), modified gingival index (MGI), pocket depth (PD), implant stability (IS), and vertical bone loss (VBL) were measured at prosthesis delivery (T0), and 6 (T6) and 12 months (T12) after delivery. The oral health impact profile (OHIP-14) questionnaire was used to assess oral health-related quality of life (OHRQoL) at T12. Significant differences between observation times were performed using Friedman and Wilcoxon signed-rank tests for MPI and MGI and using repeated measures ANOVA with Bonferroni correction of P values for PD, IS, VBL, and OHIP. Between-group comparison of MPI and MGI the Mann-Whitney test was used, while for PD, IS, VBL, and OHIP comparison was made using independent samples t test (α=.05 for all tests). The implant survival rates were 100% for both groups. MPI and PD significantly increased with time for both groups. MGI significantly increased with time for the CSL group only (P=.049). The IS significantly decreased with time for the IOD group. VBL increased significantly from T6 to T12 for the CSL (P=.042) and the IOD (P=.002) groups. The CSL group recorded higher MPI, MGI, PD, and IS values than the IOD group (P<.05). The IOD group recorded higher VBL than the CSL group (P<.001). The CSL group scored significantly lower OHIP-14 values (better OHRQoL) than the IOD group for all values (P<.05). In comparison with implant-assisted partial overdentures, closed sinus lift with fixed prostheses had higher implant stability, reduced bone loss, and higher participant OHRQoL. However, peri-implant soft tissue health was found to be better with implant overdentures.