A 3-Year Prospective Study on a Porcine-Derived Acellular Collagen Matrix to Re-Establish Convexity at the Buccal Aspect of Single Implants in the Molar Area: A Volumetric Analysis

Abstract

Background: Xenogeneic soft tissue substitutes are currently being investigated as an alternative to subepithelial connective tissue grafts (CTG) with the intention to avoid postoperative morbidity associated with autologous grafting. The aim of the present study was to volumetrically evaluate the effectiveness and mid-long-term stability of a porcine-derived collagen matrix (PDCM) (Mucoderm®, Botiss gmbh, Berlin, Germany) in increasing soft tissue volume at the buccal aspect of molar implant sites. Methods: Periodontally healthy non-smoking patients with a single tooth gap in the molar area were selected for a prospective case series. All sites had a bucco-oral bone dimension of at least 8 mm and demonstrated a horizontal alveolar defect. A wide diameter implant was placed under the elevated buccal flap and a PDCM was applied. The primary outcome was the linear increase in buccal soft tissue profile (BSP) within a well-defined area of interest. This was performed with designated software (SMOP; Swissmeda AG, Zurich, Switzerland) on the basis of superimposed digitalized study casts taken before surgery (T0), immediately after surgery (T1), at three months (T2), one year (T3) and three years (T4). Secondary outcomes were alveolar process deficiency and clinical parameters. Results: Fourteen out of 15 treated patients attended the three-year re-assessment (four females; mean age 51.4 years). Mean linear increase in BSP at T1 was 1.53 mm (p = 0.001). The PDCM showed substantial resorption at T2 (1.02 mm or 66.7%) (p = 0.001). Thereafter, a 0.66 mm volume gain was observed (p = 0.030), possibly due to the installation of a permanent crown displacing the soft tissues to the buccal aspect. This resulted in a linear increase in BSP of 1.17 mm (76.5%) at T4. Alveolar process deficiency significantly reduced over time (p = 0.004). However, 50% of patients still demonstrated a slight (6/14) or obvious (1/14) alveolar process deficiency at study termination. Implants demonstrated healthy clinical conditions. Conclusions: The PDCM demonstrated marked resorption during the early stages of healing. Due to the matrix thickening the tissues, and the permanent crown displacing the tissues, 76.5% of the initial increase in BSP could be maintained over a three-year period. Half of the patients failed to show perfect soft tissue convexity at the buccal aspect.

Immediate implant placement with or without connective tissue graft: A systematic review and meta‐analysis

“…Another concern with respect to CTG relates to increased patient morbidity due to the need for a second surgical site (Thoma et al, 2014). Therefore, there is strong scientific interest for the development and clinical evaluation of non‐autogenous collagen matrices (Eeckhout et al, 2020; Thoma et al, 2016, 2020; Zeltner et al, 2017). In the present systematic review, post‐operative complications hardly occurred (Migliorati et al, 2015; Yoshino et al, 2014; Zuiderveld et al, 2018) and patient satisfaction was high (van Nimwegen et al, 2018; Zuiderveld et al, 2018).…”

Volumetric changes at implant sites: A systematic appraisal of traditional methods and optical scanning‐based digital technologies

“…Thirty‐two of the included studies (Basler et al, 2018; Benic et al, 2017; Bertl et al, 2017; Bittner et al, 2020; Borges et al, 2020; Cabanes‐Gumbau et al, 2019; Canullo et al, 2018; Clementini et al, 2020; De Bruyckere et al, 2020; Eeckhout et al, 2020; Fischer et al, 2019; Friberg & Jemt, 2012; Galarraga‐Vinueza et al, 2020; Hinze et al, 2018; Hosseini et al, 2020; Huber et al, 2018; Jiang et al, 2020; Papi et al, 2020; Parvini et al, 2020; Rojo et al, 2018, 2020; Sanz Martin et al, 2016; Sanz‐Martin et al, 2019; Sapata et al, 2018; Schneider et al, 2011; Thoma et al, 2020; Tian et al, 2019; van Nimwegen et al, 2018; Wang et al, 2019; Wei et al, 2019; Wittneben et al, 2016; Zeltner et al, 2017) assessed volumetric changes with optical scanning‐based digital technologies. Among them, four studies also assessed mucosal thickness (MT) changes with transgingival piercing methods (Hosseini et al, 2020; Huber et al, 2018; Papi et al, 2020; Thoma et al, 2020).…”

“…Twenty‐one studies (Basler et al, 2018; Benic et al, 2017; Bittner et al, 2020; Canullo et al, 2018; Clementini et al, 2020; De Bruyckere et al, 2020; Eeckhout et al, 2020; Fischer et al, 2019; Friberg & Jemt, 2012; Hinze et al, 2018; Hosseini et al, 2020; Huber et al, 2018; Sanz Martin et al, 2016; Sanz‐Martin et al, 2019; Sapata et al, 2018; Schneider et al, 2011; Thoma et al, 2020; van Nimwegen et al, 2018; Wang et al, 2019; Wittneben et al, 2016; Zeltner et al, 2017) reported generating 3D digital models from constructed dental casts obtained with different impression materials (including silicone, alginate, polyether, and polyvinyl siloxane) with the use of desktop 3D optical scanners (indirect technique). The other eleven studies (Bertl et al, 2017; Borges et al, 2020; Cabanes‐Gumbau et al, 2019; Galarraga‐Vinueza et al, 2020; Jiang et al, 2020; Papi et al, 2020; Parvini et al, 2020; Rojo et al, 2018, 2020; Tian et al, 2019; Wei et al, 2019) had obtained the 3D digital models with the use of intra‐oral scanners (direct technique).…”

“…Among them, six studies reported that a short‐span area was scanned (Galarraga‐Vinueza et al, 2020; Parvini et al, 2020; Rojo et al, 2018, 2020; Tian et al, 2019; Wei et al, 2019), while other articles did not provide information regarding the size of the scanned area. The method of digital model superimposition was automated (using an algorithm of the software) in fourteen studies (De Bruyckere et al, 2020; Eeckhout et al, 2020; Fischer et al, 2019; Hinze et al, 2018; Huber et al, 2018; Sanz Martin et al, 2016; Sanz‐Martin et al, 2019; Schneider et al, 2011; Thoma et al, 2020; Tian et al, 2019; van Nimwegen et al, 2018; Wang et al, 2019; Wei et al, 2019; Zeltner et al, 2017), and ‘hybrid’/semi‐automated (by selecting reproducible points prior to the algorithm or by using a semiautomatic algorithm first followed by manual alignment) in eleven studies (Basler et al, 2018; Bertl et al, 2017; Borges et al, 2020; Clementini et al, 2020; Galarraga‐Vinueza et al, 2020; Jiang et al, 2020; Papi et al, 2020; Parvini et al, 2020; Rojo et al, 2018, 2020; Sapata et al, 2018), with the remaining articles that did not specify this aspect. Three studies reported the amount of range of errors/tolerance between the two STL files during the superimposition (Bertl et al, 2017; Tian et al, 2019; Wei et al, 2019).…”

“…Additionally, in ten studies, the operator who had performed the volumetric analysis had been blinded to the interventions (Borges et al, 2020; Clementini et al, 2020; Fischer et al, 2019; Rojo et al, 2018, 2020; Sanz Martin et al, 2016; Sapata et al, 2018; Thoma et al, 2020; Wang et al, 2019; Zeltner et al, 2017). All the included studies reported the software used for the volumetric analysis, with SMOP software (Swissmeda AG) being the most utilized (14 articles) (Basler et al, 2018; Benic et al, 2017; Clementini et al, 2020; De Bruyckere et al, 2020; Eeckhout et al, 2020; Fischer et al, 2019; Hinze et al, 2018; Huber et al, 2018; Sanz Martin et al, 2016; Sanz‐Martin et al, 2019; Sapata et al, 2018; Thoma et al, 2020; van Nimwegen et al, 2018; Zeltner et al, 2017), followed by Geomagic (3D systems) in eight studies (Borges et al, 2020; Jiang et al, 2020; Papi et al, 2020; Rojo et al, 2018, 2020; Tian et al, 2019; Wang et al, 2019; Wei et al, 2019) (Table 1). Comparison of the volumetric outcomes using different software was not explored among the included studies.…”