Randomized controlled clinical study evaluating effectiveness and safety of a volume‐stable collagen matrix compared to autogenous connective tissue grafts for soft tissue augmentation at implant sites

Abstract

Aim To test whether or not the use of a collagen matrix (VCMX) results in short‐term soft tissue volume increase at implant sites non‐inferior to an autogenous subepithelial connective tissue graft (SCTG), and to evaluate safety and tissue integration of VCMX and SCTG. Methods In 20 patients with a volume deficiency at single‐tooth implant sites, soft tissue volume augmentation was performed randomly allocating VCMX or SCTG. Soft tissue thickness, patient‐reported outcome measures (PROMs), and safety were assessed up to 90 days (FU‐90). At FU‐90 (abutment connection), tissue samples were obtained for histological analysis. Descriptive analysis was computed for both groups. Non‐parametric tests were applied to test non‐inferiority for the gain in soft tissue thickness at the occlusal site. Results Median soft tissue thickness increased between BL and FU‐90 by 1.8 mm (Q1:0.5; Q3:2.0) (VCMX) (p = 0.018) and 0.5 mm (−1.0; 2.0) (SCTG) (p = 0.395) (occlusal) and by 1.0 mm (0.5; 2.0) (VCMX) (p = 0.074) and 1.5 mm (−2.0; 2.0) (SCTG) (p = 0.563) (buccal). Non‐inferiority with a non‐inferiority margin of 1 mm could be demonstrated (p = 0.020); the difference between the two group medians (1.3 mm) for occlusal sites indicated no relevant, but not significant superiority of VCMX versus SCTG (primary endpoint). Pain medication consumption and pain perceived were non‐significantly higher in group SCTG up to day 3. Median physical pain (OHIP‐14) at day 7 was 100% higher for SCTG than for VCMX. The histological analysis revealed well‐integrated grafts. Conclusions Soft tissue augmentation at implant sites resulted in a similar or higher soft tissue volume increase after 90 days for VCMX versus SCTG. PROMs did not reveal relevant differences between the two groups.

Volumetric and linear changes at dental implants following grafting with volume-stable three-dimensional collagen matrices or autogenous connective tissue grafts: 6-month data

“…During further healing, remodeling processes of soft tissue transplants and soft tissue substitutes are common and were described in previous preclinical and clinical experiments [16,20,27,28]. Moreover, it has also been observed that the tissues underlying the soft tissue grafts undergo remodeling processes as well [18].…”

“…In vitro and preclinical data showed favorable histological and volumetric results in terms of tissue integration and volume gain [17][18][19]. Although recent clinical data show similar volume gain when 4 augmenting implant sites with SCTG or VCMX [20], long term data monitoring volume changes at implant sites are still scarce .…”

Extracellular matrix‐based scaffolding technologies for periodontal and peri‐implant soft tissue regeneration

“…51,52 VCMX is made of collagen and * Geistlich Pharma, Wolhusen, Switzerland. This graft has also been called volume-stable collagen matrix (VCMX) since one of its main advantages is the ability to maintain a good volume stability.…”

“…This graft has also been called volume-stable collagen matrix (VCMX) since one of its main advantages is the ability to maintain a good volume stability. 51,52,54 In contrast to CM that has been used also in an open environment, VCMX requires a submerged healing. undergoes a cross-linking providing volume stability and some elasticity at the same time.…”

Basic Principles of Bioengineering and Regeneration

“…63–65 These collagen matrices are treated like gingival or subepithelial connective tissue but are a nonautogenous tissue substitute. Although they have some preliminarily favorable results, the success is limited to small and simple defects.…”