Soft tissue stability and volumetric changes after 5years in pontic sites with or without soft tissue grafting: a retrospective cohort study.

Abstract

To evaluate volumetric changes (VC) of pontic sites with or without soft tissue grafting over 5years. Twelve patients participating in a prospective clinical trial evaluating fixed dental prostheses (FDPs) were selected on the basis of having received a subepithelial connective tissue graft for soft volume augmentation in pontic sites (augmentation group [AG]). An additional 12 patients, belonging to the same study, that had not received soft tissue grafting were used as controls (control group [CG]). Casts made from dental impressions taken at prosthesis delivery (baseline [BL]) and at 5years (5-FU) were digitized, and linear and volumetric measurements performed to assess the soft tissue pontic height (PH), abutment height (AH), (VC) and changes in tissue thickness (TT) on the buccal side of the pontics. There were no significant differences at BL between the two groups for linear measurements (P>0.05). The changes in soft tissue pontic height (PHC) amounted to a loss in the height of 0.34mm (SD=0.5) and 0.35mm (0.2) for AG and CG, respectively. The mean VC amounted to a loss of 5.31mm(3) (±1.1) (AG) and 4.32mm(3) (±1.7) (CG). None of the changes between BL and 5-FU in volumetric and linear measurements, including TT and mean mesial and distal abutment height changes (mAHC and dAHC), reached statistically significant differences between AG and CG (P>0.05). However the changes in linear measurements from BL to 5-FU were significant in all parameters for both groups (P<0.01). At an observational period of 5years, pontic sites with or without grafting under FDPs demonstrated similar dimensional stability. Pontic sites with or without grafting are volumetrically stable over 5years.