Soft and hard tissue changes after immediate implant placement with or without a sub-epithelial connective tissue graft: Results from a 6-month pilot randomized controlled clinical trial.

AIM: The present pilot RCT aimed to investigate the influence of a connective tissue graft (CTG) in combination with the immediate implant placement (IIP) on hard and soft tissue healing, without a bone replacement graft in the gap between the implant and the socket walls. MATERIALS AND METHODS: Thirty patients requiring extraction of one anterior tooth (from premolar to premolar) were randomly assigned to one of the two treatment groups (test: IIP + CTG; control: IIP). Cone-beam computed tomography and optically scans were performed before tooth extraction and at 6-month follow-up. Then, DICOM files were superimposed in order to allow the evaluation of osseous ridge and buccal bone changes, while the superimposition of DICOM and Standard Tessellation Language files allowed for evaluating of soft tissue contour. For testing the differences between the two groups, the non-parametric test as Wilcoxon rank-sum test, was used. RESULTS: Twenty-six of the 30 enrolled patients attended the 6-month follow-up visit. The four patients of the control group that were lost to follow-up were analysed under the intention-to-treat principle. No statistically significant differences between the groups were observed for the vertical buccal bone resorption (p = .90), as well as for the horizontal buccal bone resorption at all measured levels. Significant differences were found between the test and control groups in the horizontal dimensional changes of osseous ridge at the most coronal aspect (p = .0003 and p = .02). Changes in tissue contour were between -0.32 and -0.04 mm in the test group and between -1.94 and -1.08 mm in the control group, while changes in soft tissue thickness varied between 1.33 and 2.42 mm in the test group and between -0.16 and 0.88 mm in the control group, with statistically significant differences for both variables at all measured levels. At 6 months, the mean volume increase was 6.76 ± 8.94 mm3 and 0.16 ± 0.42 mm3 in the test and control groups, respectively, with a statistically significant difference. CONCLUSIONS: The findings of the present study indicate that the adjunct of a CTG at the time of IIP, without bone grafting, does not influence vertical bone resorption. Within the limits of this study, it can be suggested that the adjunct of a CTG at the time of IIP, without bone grafting, reduces the horizontal changes of the alveolar ridge. Moreover, it allows maintenance of the tissue contour due to an increase in soft tissue thickness.

The effect of immediate implant placement on alveolar ridge preservation compared to spontaneous healing after tooth extraction: Soft tissue findings from a randomized controlled clinical trial.

AIM: To compare soft tissue dimensional changes and relative differences in soft and hard tissue volumes 4 months after single-tooth extraction and three different treatment modalities: spontaneous healing (SH) and alveolar ridge preservation by means of a deproteinized bovine bone mineral and a collagen matrix, with (IMPL/DBBM/CM) or without (DBBM/CM) immediate implant placement. MATERIALS AND METHODS: STL files from study casts obtained at baseline and after 4 months were matched to calculate buccal soft tissue linear and volumetric changes. DICOM files from CBCTs were superimposed to STL files allowing the evaluation of soft tissue thickness at baseline and 4 months. RESULTS: Mean horizontal reduction accounted for 1.46 ± 0.20 (SH), 0.85 ± 0.38 (DBBM-CM) and 0.84 ± 0.30 IMPL/DBBM-CM, with no statistical differences. Soft tissue thickness had a significant mean increase of 0.95 for SH group, compared to a non-significant mean decrease for DBBM-CM (0.20) and IMPL/DBBM-CM groups (0.07). CONCLUSION: A preservation technique with DBBM-CM, with or without immediate implant placement, did not reduce the horizontal linear and volumetric changes at the buccal soft tissue profile significantly at 4 months after tooth extraction when compared to spontaneous healing. This is due to a significant increase in soft tissue thickness in spontaneously healing sites.