Radiographic and Histomorphometric Evaluation of Biomaterials Used for Lateral Sinus Augmentation: A Systematic Review on the Effect of Residual Bone Height and Vertical Graft Size on New Bone Formation and Graft Shrinkage

Abstract

The aim of the present systematic review was to investigate the effect of residual bone height (RBH) and vertical bone gain on new bone formation (NBF) and graft shrinkage after lateral sinus lifts using different biomaterials. Methods: An electronic search was conducted on three databases to identify randomized controlled trials (RCTs) published until January 2021 with at least one follow-up at 6 months and at least five patients treated, comparing biomaterials used for maxillary sinus augmentation with a lateral approach. Graft volumetric changes, RBH, vertical bone gain, implant failure, and post-operative complications were evaluated. The risk of bias was assessed using the Cochrane tool. Results: We used 4010 identified studies, of which 21 were RCTs. Overall, 412 patients and 533 sinuses were evaluated. Only three publications had an overall low risk of bias. After 6 months, xenograft (XG) showed the least volume reduction (7.30 ± 15.49%), while autogenous graft (AU) was the most reabsorbed (41.71 ± 12.63%). NBF appeared to not be directly correlated with RBH; on the contrary, the overall linear regression analysis showed that NBF significantly decreased by 1.6% for each mm of postoperative vertical graft gain. This finding suggests that the greater the augmentation, the lower the NBF. A similar tendency, with a regression coefficient even higher than the overall one, was also observed with alloplast (AP) and XG. Conclusions: The present results suggested that NBF was essentially independent of preoperative bone height. On the contrary, the smaller the volume was of the graft placed, the higher the amount of new bone formed, and the smaller the graft shrinkage was. Minimizing the augmentation volume might be beneficial to graft healing and stability especially when using AP and XG.

Bone Graft Packing and Its Association with Bone Regeneration in Maxillary Sinus Floor Augmentations: Histomorphometric Analysis of Human Biopsies

“…A low BS volume, by contrast, did not seem to impede bone regeneration in this setting. This is in accordance with histological observations and a recent systematic review by Pesce et al reporting that the presence of a larger volume of BS particles did not necessarily results in a larger volume of nB formation [ 53 ]. These findings suggest that a high graft packing density through excessive compaction of BS particles should be avoided in order to optimise the macrostructural environment for bone regeneration after MSFA.…”

Does new bone formation vary in different sites within the same maxillary sinus after lateral augmentation? A prospective histomorphometric study

“…No correlation was demonstrated between RBH and %NFMT: this outcome is consistent with many other studies demonstrating that graft remodelling into new bone was not significantly influenced by residual alveolar bone height (Avila et al, 2010;Pesce et al, 2021;Pignaton et al, 2019;Stacchi et al, 2018;Taschieri et al, 2020;Zhou et al, 2021). From which does not give information about possible further graft consolidation in longer healing periods, as showed in other studies (Soardi et al, 2011).…”

“…No correlation was demonstrated between RBH and %NFMT: this outcome is consistent with many other studies demonstrating that graft remodelling into new bone was not significantly influenced by residual alveolar bone height (Avila et al, 2010 ; Avila‐Ortiz, Neiva, et al, 2012 ; Pesce et al, 2021 ; Pignaton et al, 2019 ; Stacchi et al, 2018 ; Taschieri et al, 2020 ; Zhou et al, 2021 ). From these findings, RBH should not be considered as a possible indicator of the regenerative potential of the site to be augmented, but only as a predictive factor for immediate implant placement (Stacchi et al, 2020 ).…”

One‐stage versus two‐stage technique using two splinted extra‐short implants: A multicentric split‐mouth study with a one‐year follow‐up

“…Several surgical techniques have been developed over the years to face this clinical situation, including guided bone regeneration (GBR), block grafts, sinus lift, bone distractions, alveolar nerve transposition, mediodistally tilted implants or the use of pterygoid or zygomatic implants. [1][2][3][4][5][6][7] However, these surgical procedures can result in a long treatment time, high costs, and morbidity. 8,9 For these reasons, short and extra-short implants have been proposed as a simplified minimally invasive alternative, to adapt implants macrostructure to the existing anatomy, reducing biological and economical costs, treatment time, and increasing patient acceptance.…”