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Objective: To investigate the early impact of plaque accumulation in a buccal dehiscence defect on peri‐implant marginal bone resorption. Materials and Methods: In six male Mongrel dogs, four dental implants were placed in the posterior maxilla on both sides (two implants per side). Based on the group allocation, each implant was randomly assigned to one of the following four groups to decide whether buccal dehiscence defect was prepared and whether silk ligation was applied at 8 weeks post‐implant placement for peri‐implantitis induction: UC (no defect without ligation); UD (defect without ligation); LC (no defect with ligation); and LD (defect with ligation) groups. Eight weeks after disease induction, the outcomes from radiographic and histologic analyses were statistically analyzed (p <.05). Results: Based on radiographs, the exposed area of implant threads was smallest in group UC (p <.0083). Based on histology, both the distances from the implant platform to the first bone‐to‐implant contact point and to the bone crest were significantly longer in the LD group (p <.0083). In the UD group, some spontaneous bone fill occurred from the base of the defect at 8 weeks after implant placement. The apical extension of inflammatory cell infiltrate was significantly more prominent in the LD and LC groups compared to the UC group (p <.0083). Conclusion: Plaque accumulated on the exposed implant surface had a negative impact on maintaining the peri‐implant marginal bone level, especially when there was a dehiscence defect around the implant. [ABSTRACT FROM AUTHOR]

Objective: To histomorphometrically determine the effects of hard‐ and/or soft‐tissue augmentation by applying the early implant placement protocol. Materials and Methods: The distal roots of the maxillary second and third premolars were extracted in 10 mongrel dogs. After 1 month, early implant placement was performed in the distal roots, resulting in buccal dehiscence defects. Four treatments were then randomly applied: (1) guided bone regeneration (GBR), (2) connective tissue grafting (CTG), (3) simultaneous GBR and CTG (GBR + CTG) and (4) no further treatment (control). Healing abutments were connected to all implants to allow non‐submerged healing. At 4 and 16 weeks, tissue sections were harvested and histomorphometric analyses were performed. Results: Group GBR presented the largest total tissue thickness at 4 weeks, but underwent a greater remodelling compared with the other groups between 4 and 16 weeks. At 16 weeks, the overall tissue thickness was largest in group GBR + CTG. This group was also the most favourable in terms of the level of the margo mucosae and the presence of mineralized tissue at the coronal level. Group CTG demonstrated a stable tissue thickness over time, with a larger thickness at 16 weeks compared with group GBR. Conclusion: Simultaneous CTG and GBR resulted in the most‐favourable tissue thickness when applying the early implant placement protocol. [ABSTRACT FROM AUTHOR]

Aim Methods Results Conclusion To evaluate the efficacy of guided bone regeneration (GBR) for the treatment of peri‐implant dehiscence defects using a synthetic bone substitute (SBS) or a deproteinized bovine bone mineral (DBBM) as a bone substitute.Patients with expected dehiscence defects following implant placement were randomized to use either SBS or DBBM together with a bioabsorbable collagen membrane over dehiscenced implant surfaces aimed for GBR. The changes in the bone defect size were measured before the GBR procedure and 6 months after implant placement at the re‐entry surgery. Secondary outcomes included peri‐implant health outcomes, implant cumulative survival rates, bone level changes, and patient‐reported outcomes (PROMs) at prosthesis delivery and 1‐year follow‐up.Of the 49 included patients, 24 were treated with SBS and 25 with DBBM. In the SBS group, the defect height (DH) at implant insertion was 5.1 ± 2.6 mm and was reduced at re‐entry to 1.3 ± 2.0 mm (74.5%). In the DBBM group, the respective changes in DH were 4.1 ± 1.7 mm and 1.5 ± 1.9 mm (63.4%). These differences were not statistically significant (p = 0.216). The complete defect resolution rate was also comparable in both groups without statistical difference (62.5% of patients (15/24) vs. 44% of patients (11/25)). Overall, the marginal bone levels remained stable during the 1‐year follow‐up in both groups.The SBS is noninferior to DBBM for simultaneous GBR to implant placement at implant sites with buccal dehiscences in terms of defect resolution and evaluated secondary outcomes (KCT0008393 − this clinical trial was not registered before participant recruitment and randomization). [ABSTRACT FROM AUTHOR]

Objectives: To evaluate clinical, clinician‐ and patient‐reported outcomes (PROs) of two adjacent single posterior implants immediately loaded with definitive single crowns up to 1 year. Ten patients in need of two adjacent posterior single implants were included. All implants were placed applying a fully digital workflow. Definitive screw‐retained single zirconia crowns were delivered within 72 h after implant placement. Clinical parameters, patient‐ and clinician‐reported outcomes were assessed up to 1 year of follow‐up. Clinical Considerations: Clinical outcomes remained stable, with no implant failures or technical and biological complications throughout the observation period. Patient satisfaction was very high at baseline (crown delivery) and remained consistently high at 6 and 12 months of follow‐up. Crown insertion 3 days after implant placement was rated as an easy procedure by clinicians. Conclusions: Two adjacent single implants with immediate definitive restorations (<72 h) in the posterior region appear to be a viable and easy treatment option to shorten the overall treatment time and potentially enhancing patient satisfaction. However, randomized controlled trials are needed to confirm the advantages of this treatment protocol over a delayed loading approach. Clinical Significance: In selected cases, immediate implant loading with definitive restorations in the posterior region appears a valuable and straightforward option to shorten the overall treatment time. [ABSTRACT FROM AUTHOR]

Aim: To test whether early implant placement into the extraction socket containing an uncalcified provisional matrix leads to successful osseointegration and stable marginal bone levels. Materials and Methods: In six mongrel dogs, the mandibular molars were extracted. Three weeks later, early implant placement was performed according to three experimental protocols: (i) flapless implant placement with preservation of the provisional matrix; (ii) flap elevation, socket debridement and implant placement; and (iii) flap elevation, socket debridement, implant placement and guided bone regeneration (GBR). One untreated extraction socket served as a control group. Data analyses were based on histologic slides 3 months after implant placement. Results: There were no differences in bone‐to‐implant contact between the three experimental groups (66.97%, 58.89% and 60.89%, respectively) (inter‐group comparison p =.42). Marginal bone levels, first bone‐to‐implant contact as well as the thickness of the connective tissue did not reveal any significant differences between the groups (p =.85,.60 and.65, respectively). Conclusions: Flapless early implant placement into posterior extraction sockets was as effective as an open flap approach in conjunction with GBR. Mineralization of the socket seems to occur irrespective of the presence of dental implants or biomaterials. [ABSTRACT FROM AUTHOR]

Aim: To histomorphometrically assess three treatment modalities for gaining keratinized tissue (KT) at teeth and at dental implants. Materials and Methods: In five dogs, the distal roots of the mandibular second, third and fourth premolars were extracted. Dental implants were placed at the distal root areas 2 months later. After another 2 months, KT augmentation was performed at both distal (implants) and at mesial root (teeth) areas in the presence (wKT groups) or absence (w/oKT groups) of a KT band at the mucosal/gingival level. Three treatment modalities were applied randomly: apically positioned flap only (APF), free gingival grafts (FGGs) and xenogeneic collagen matrices (XCMs). A combination of the above produced six groups. Two months later, tissue sections were harvested and analysed histomorphometrically. Results: The median KT height and length were greatest at implants with FGG in both wKT (3.7 and 5.1 mm, respectively) and w/oKT groups (3.7 and 4.6 mm), and at teeth with FGG in wKT groups (3.7 and 6.1 mm) and with APF in the w/oKT groups (3.9 and 4.4 mm). The XCM and APF produced more favourable results at teeth than at implants. Conclusions: FGG was advantageous in gaining KT, especially at implants. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the effect of a self‐retaining block‐type bone substitute (srBB) on the dimensional stability of the horizontal ridge width at the coronal level in a buccal dehiscence model. Materials and Methods: Four box‐shaped bone defects with a buccal dehiscence were surgically prepared in the partially edentulous mandible (n = 6). Experimental biomaterials were randomly assigned to each site: (1) Control group: no treatment, (2) particle‐type bone substitute (PBS) group, (3) collagenated soft block bone substitute (csBB) group, and (4) self‐retaining synthetic block bone (srBB) group. In all grafted groups, a collagen membrane covered the biomaterials. At 16 weeks, clinical, histological, and radiographic analyses were performed. Results: Three of the six blocks in the srBB group became exposed and fell out during the first week after surgery. Therefore, the remaining three specimens were renamed RsrBB group. The RsrBB group showed an increase horizontal ridge compared to the pristine bone width at 2–4 mm below the CEJ, while the other groups showed resorption (augmented width at 2 mm below: 4.2, 42.4, 36.2, and 110.1% in the control, PBS, csBB, and RsrBB groups, respectively). The mineralized bone area was largest in the RsrBB group (4.74, 3.44, 5.67, and 7.77 mm2 in the control, PBS, csBB, and RsrBB groups, respectively.). Conclusions: The srBB group demonstrated the highest volume stability at the coronal level. These findings would potentially suggest that self‐retaining block bone substitute might be a good candidate for alveolar ridge preservation. [ABSTRACT FROM AUTHOR]

Aim: To investigate whether transmucosal healing is as effective as submerged healing in terms of buccal bone regeneration when guided bone regeneration (GBR) is performed simultaneously with implant placement. Materials and Methods: In six dogs, buccal dehiscence defects were created in the edentulous mandibular ridge, sized 5 × 5 × 3 mm (length × height × depth). In each defect, a bone‐level implant was placed, and four experimental groups were randomly assigned as follows: (i) transmucosal healing with GBR (T‐GBR), (ii) transmucosal healing without GBR (T‐control), (iii) submerged healing with GBR (S‐GBR) and (iv) submerged healing without GBR (S‐control). Data analyses were based on histological slides 5 months after implant placement. Results: The T‐GBR group showed significant differences compared to the control groups regarding defect height resolution, buccal bone thickness and mineralized tissue area (p <.05), but showed no significant differences when compared with the S‐GBR group (p >.05). Conclusions: The mode of healing (transmucosal vs. submerged) does not influence bone regeneration at implant sites. The clinician may therefore choose the approach based on further clinical and patient‐specific parameters. [ABSTRACT FROM AUTHOR]