A multi-centre randomized controlled trial on alveolar ridge preservation with immediate or delayed implant placement: Need for soft-tissue augmentation

Soft-tissue volume augmentation during early, delayed, and late dental implant therapy: A systematic review and meta-analysis on professionally determined esthetics and self-reported patient satisfaction on esthetics

The objective of the study was to assess the effect of soft-tissue volume augmentation during early, delayed, and late dental implant therapy in terms of professionally determined esthetics and self-reported patient satisfaction on esthetics. For this, a comprehensive electronic literature search was performed to identify randomized clinical trials (RCTs) and controlled clinical trials (CCTs) reporting professionally determined esthetic outcomes and self-reported patient satisfaction on esthetics (primary outcomes) during early, delayed, and late dental implant placement comparing soft-tissue volume augmentation to the absence of soft-tissue grafting (control) (PICO 1) or comparing various soft-tissue augmentation techniques, procedures, and materials (PICO 2). Secondary outcomes were mucosal thickness (MT), intra- and postoperative complications, marginal soft-tissue-level changes, keratinized tissue width, radiographic marginal bone levels, and clinical parameters for the diagnosis of peri-implant tissue health. The standard mean differences (SMD)/weighted mean differences (WMD) were estimated for the Pink Esthetic Score (PES), self-reported patient satisfaction assessed by Visual Analog Scale (VAS) and MT gain for PICO 1 and PICO 2 by employing a random effect model. Five RCTs were included for PICO 1, whereas 7 RCTs and 1 CCT addressed PICO 2. PICO 1: The SMD for the PES between autogenous soft-tissue grafting (SCTG) and the absence of grafting (control group) was 0.47; 95% CI [-0.15, 1.09; p = 0.14] based on 5 RCTs. The SMD for the VAS values for patient-reported satisfaction on esthetics in the SCTG and control group was 0.46; 95% CI [-0.12, 1.03; p = 0.12] (2 RCTs). The WMD for gain of MT amounted to 1.06 mm; 95% CI [0.81, 1.31; p = 0.00] in favor of the SCTG group (3 RCTs). PICO 2: The SMD for the PES comparing collagen-based matrices (CM group) to the SCTG group was -0.32; 95% CI: (-0.57, -0.07; p = 0.01), in favor of the SCTG group (5 RCTs and 1 CCT). The SMD for the VAS for patient-reported satisfaction on soft-tissue esthetics was 0.24; 95% CI: (-0.31, 0.78; p = 0.40) (2 RCTs comparing CM vs. SCTG). The WMD for gain of MT was -0.27 mm; 95% CI: (-0.36, -0.17; p = 0.00), significantly favoring the SCTG group (4 RCTs). Professionally and patient-assessed outcomes showed no substantial differences between autogenous soft-tissue grafting and the absence of grafting for early, delayed, and late implant placement. However, autogenous soft-tissue grafts led to significantly improved esthetic outcomes as assessed by professionals compared to soft-tissue substitutes. Patient-assessed outcomes, nevertheless, were similar regardless of the grafting material (i.e., SCTG or soft-tissue substitute). Therefore, autogenous soft-tissue grafting, though, resulted in a considerably higher gain in mucosal thickness compared to both the absence of soft-tissue grafting and the use of soft-tissue substitutes. Complications and adverse events were rarely reported by the included studies, thus suggesting that many trials underreport harms (e.g., complications).

A Systematic Review on Immediate Implant Placement in Intact Versus Non-Intact Alveolar Sockets

Objectives: The primary objective of this systematic review was to compare IIP in intact versus non-intact sockets in terms of buccal bone thickness. Methods: Two independent reviewers carried out an electronic literature search in PubMed, Web of Science, Embase, and Cochrane databases as well as a manual search to identify eligible clinical studies up to June 2024. Randomized controlled trials (RCTs), cohort studies, and case series on intact and/or non-intact sockets were included for analysis. The primary outcome was buccal bone thickness (BBT). Secondary outcomes were vertical midfacial soft tissue level change, pink esthetic score (PES), implant survival and complications. This systematic review was conducted in accordance with the PRISMA guidelines. Results: After screening 1001 unique titles and conducting manual searches, 20 articles reporting on 525 implants (intact: 265; non-intact: 260) in the anterior maxilla with a follow-up of up to 120 months were selected. The overall study quality was low, especially for non-intact sockets since only two RCTs could be found, and none demonstrated a low risk of bias. Meta-analyses were not feasible due to a lack of direct comparisons, and heterogeneity in terms of surgical approach, soft tissue handling, and restorative approach. BBT ranged between 1.10 and 3.18 mm (intact) and 1.18 and 3 mm (non-intact). Vertical midfacial soft tissue level change ranged between -0.13 and -0.58 mm (intact) and -0.03 and -0.59 mm (non-intact). Pink esthetic scores ranged between 10.48 and 12.80 (intact) and 9.25 and 12.43 (non-intact). Implant survival exceeded 90% in all studies and was 100% in the vast majority of the studies. Conclusions: This systematic review suggests a similar outcome of IIP in intact and non-intact sockets. However, the overall low study quality, a lack of direct comparisons, and heterogeneity rendered the comparison highly biased. Future studies should be conducted to establish an evidence-based treatment approach for IIP in non-intact sockets.

A Randomized Controlled Trial on the Timing of Soft Tissue Augmentation in Immediate Implant Placement: Soft Tissue Changes and Esthetic Outcome

AIM

To assess the impact of the timing of soft tissue augmentation on soft tissue changes and esthetic outcome following single immediate implant placement (IIP) in the anterior maxilla.

MATERIALS AND METHODS

Patients with a failing tooth and intact buccal bone wall in the anterior maxilla (15-25) were enrolled in this RCT. Following single IIP and socket grafting, they were randomly allocated to the control group (immediate soft tissue augmentation performed in the same surgical procedure-ISTA) or the test group (delayed soft tissue augmentation performed 3 months later-DSTA). Implants were placed with a surgical guide and immediately restored with an implant-supported provisional crown. Changes in soft tissue dimensions were assessed by a blinded clinician using superimposed STL files taken prior to surgery and at 1-year follow-up. The esthetic outcome was rated by a blinded clinician and the patient at 1-year follow-up. The study adhered to the STA-COSM (Soft Tissue Augmentation-Core Outcome Set and Measurements for implant dentistry trials) guidelines.

RESULTS

Twenty patients were randomized to each group (control: 16 females, 4 males, mean age 57.6; test: 9 females, 11 males, mean age 54.2). The mean change in buccal soft tissue profile was -0.251 and 0.083 mm for ISTA and DSTA, respectively. The mean difference of -0.318 mm in favor of DSTA was not significant (95% CI: -0.860 to 0.224, p = 0.241). Median midfacial recession was -0.200 and - 0.350 mm for ISTA and DSTA, respectively. The median difference of 0.200 mm in favor of ISTA was not significant (95% CI: -0.210 to 0.700, p = 0.311). Mesial and distal papillary recession, Pink Esthetic Score and patients' esthetic satisfaction failed to demonstrate a significant difference between the groups.

CONCLUSION

In patients with an intact buccal bone wall, the timing of soft tissue augmentation following IIP had no significant impact on soft tissue changes and esthetic outcome.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT05537545.

A multi-centre randomized controlled trial comparing connective tissue graft with collagen matrix to increase soft tissue thickness at the buccal aspect of single implants: 3-Year results

AIM

To compare connective tissue graft (CTG) with collagen matrix (CMX) in terms of increase in buccal soft tissue profile (BSP) when applied at single implant sites.

MATERIALS AND METHODS

Patients with a single tooth gap in the anterior maxilla and horizontal mucosa defect were enrolled in a multi-centre randomized controlled trial. All were fully healed sites with a bucco-palatal bone dimension of at least 6 mm, and received an immediately restored single implant using a full digital workflow. Patients were randomly allocated to the control (CTG) or test group (CMX: Geistlich Fibro-Gide, Geistlich Pharma AG, Wolhusen, Switzerland) to increase buccal soft tissue thickness. Primary endpoints were increase in BSP at T1 (immediately postop), T2 (3 months), T3 (1 year) and T4 (3 years) based on superimposed digital surface models. Secondary endpoints included patient-reported, clinical and aesthetic outcomes.

RESULTS

Thirty patients were included per group (control group: 15 males, 15 females, mean age 50.1 years; test group: 14 males, 16 females, mean age 48.2 years) and 50 could be re-examined at T4. The changes in BSP over time were significantly different between the groups (p < .001). At T4, the estimated mean increase in BSP amounted to 0.83 mm (95% confidence interval [CI]: 0.58-1.08) in the control group and 0.48 mm (95% CI: 0.22-0.73) in the test group. The estimated mean difference of 0.35 mm (95% CI: 0.06-0.65) in favour of the control group was significant (p = .021). No significant differences between the groups could be observed in terms of patients' aesthetic satisfaction (p = .563), probing depth (p = .286), plaque (p = .676), bleeding on probing (p = .732), midfacial recession (p = .667), Pink Esthetic Score (p = .366) and Mucosal Scarring Index (p = .438). However, CMX resulted in significantly more marginal bone loss (-0.43 mm; 95% CI: -0.77 to -0.09; p = .015) than CTG.

CONCLUSIONS

CTG was more effective in increasing buccal soft tissue profile and resulted in less marginal bone loss than CMX. Therefore, CTG remains the gold standard to increase soft tissue thickness at implant sites.

CLINICAL TRIAL REGISTRATION

This study was registered in ClinicalTrials.gov (NCT04210596).

Feasibility of Immediate, Early and Delayed Implant Placement for Single Tooth Replacement in the Premaxilla: A Retrospective Cone-Beam Computed Tomography Study of 100 Cases

AIM

To assess the feasibility of immediate (IIP), early (EIP) and delayed implant placement (DIP) for single tooth replacement in the premaxilla on the basis of the complete indication area of each approach in routine practice.

MATERIALS AND METHODS

Data from 100 patients (59 women, 41 men, all Caucasians) aged between 19 and 81 years old (mean age 51.71) who had been consecutively treated with a single implant in the premaxilla (13-23) in one private periodontal practice were retrospectively collected. Demographic data, diagnostic information and linear measurements were extracted from patient files and CBCTs. The feasibility of IIP, EIP and DIP was assessed for all cases by both authors, based on the following criteria: availability of apical bone, position of the tooth in relation to the morphology of the alveolar process, buccal bone morphology and presence of midfacial recession. The reasons for not being able to perform an approach, and the viable alternatives for each approach were secondary outcomes. DIP was considered to have been preceded by alveolar ridge preservation (ARP).

RESULTS

Ninety-two patients could be treated by means of IIP, EIP or DIP. In eight patients none of these approaches were possible as they required bone augmentation prior to implant placement. Fifty-two patients (95% CI: 42%-62%) could by treated with IIP, 58 (95% CI: 48%-67%) with EIP and 88 (95% CI: 80%-93%) with DIP. The feasibility proportions of IIP and EIP were significantly lower than the one of DIP (p < 0.001). All patients who could be treated with IIP could also be treated with EIP or DIP. Lack of apical bone for implant anchorage was the main reason for not being able to perform IIP and EIP. Complete loss of the buccal bone wall and the need for bone augmentation prior to implant placement were the reasons for not being able to perform DIP.

CONCLUSION

From the results of this retrospective CBCT analysis, DIP is nearly always possible in contrast to IIP and EIP. Therefore, and since it is much easier than IIP and EIP, inexperienced clinicians should mainly focus on ARP and DIP in clinical practice deferring IIP and EIP until more surgical skills have been acquired.

3D surface defect map for assessing buccolingual profile of single tooth gaps following alveolar ridge preservation

AIM

A new, non-invasive approach suggests using single intraoral optical scanning to analyze the ridge profile of single-tooth gaps following alveolar ridge preservation in the absence of a baseline scan. This method involves creating a three-dimensional (3D) surface map to identify and assess contour changes and ridge profiles based on the adjacent teeth.

MATERIALS AND METHODS

The present study was designed as a cross-sectional pilot analysis on a convenience sample of patients undergoing alveolar ridge preservation. Intraoral optical scans were taken on 23 patients, capturing data from 30 edentulous sites. The digital models were then imported into an image analysis software for a 3D surface defect map analysis performed by one examiner. This analysis characterized the buccolingual profile of the single tooth gap relative to the adjacent teeth. 10 linear divergence points, spaced 0.5 mm apart in a corona-apical direction, were identified at the midfacial aspect of the sites. Based on these points the sites were plotted and grouped in three different buccolingual profiles (linear, concave, and convex). Clinical parameters including Keratinized mucosa Width (KMW), and soft tissue phenotype with Colorvue biotype probes were also recorded.

RESULTS

Three different buccolingual patterns (linear, convex, and concave) were identified. Seven sites exhibited a linear profile, 10 sites displayed a concave shape, and 13 showed a convex profile. The linear profile had surface discrepancies similar to the neighboring teeth. In contrast, the convex profile revealed mid-buccal discrepancy localized only at the crestal aspect, while the concave had an extended divergence ranging from 1 to 5 mm below the soft tissue margin. Univariate and multiple logistic regression analyses did not reveal any statistically significant variables influencing profilometric analysis; however, when combining phenotype and KMW, thick phenotypes demonstrated a higher proportion of concavity (OR = 4.83) compared to thin ones, suggesting a significant trend. With every 1 mm of increase in KMW, the probability of showing a concavity decreased (p = 0.057).

CONCLUSION

A 3D surface defect map represents a useful tool for objectively quantifying ridge defects and profiles by assessing profilometric and surface differences compared to adjacent dentition using a single intraoral scan. This method also indicates that KMW may play a critical role in preventing concavity defects. The 3D defect map can guide decision-making during soft tissue augmentation procedures by emphasizing the specific location of the defect and providing more detailed insights into its localization. These parameters can enable the tailoring of flap management and soft tissue grafting strategies to address the patient's individual needs.

Early implant placement versus ridge preservation and delayed implant placement: Analysis of profilometric, clinician- and patient-reported outcomes from a two-centre RCT

OBJECTIVES

To compare early implant placement (EP) to alveolar ridge preservation and delayed implant placement (ARP/DP) in terms of contour changes, along with clinician- and patient-reported outcome measures (PROMs) until the delivery of the implant-supported restoration.

MATERIALS AND METHODS

Patients with a failing single tooth in the maxilla or mandible were recruited in two centres. After tooth extraction, patients were randomly assigned (1:1) to either EP or ARP/DP. At abutment connection and crown delivery, the buccal contour changes at 3 mm below the mucosal margin (primary outcome) along with clinician- (ease of treatment) and patient-reported outcomes were assessed using numeric rating scales and OHIP-14.

RESULTS

A total of 46 patients were analysed. The mean buccal contour at abutment connection decreased by -1.2 ± 0.6 mm in group EP and -1.6 ± 0.8 mm in group ARP/DP (estimated mean difference; 0.45 [95%CI, -0.02; 0.94]; p = .061) with no significant differences between the groups. ARP/DP was consistently easier than EP across all stages of the surgery (estimated mean difference; 2.0 [95%CI, 1.3; 2.7] p < .001): during flap elevation (EP: 4.8 vs. ARP/DP: 1.6), implant placement (EP: 5.7 vs. ARP/DP: 2.2) and wound closure (EP: 3.4 vs. ARP/DP: 1.6). Both interventions improved quality of life but patients who underwent ARP/DP were significantly more satisfied at the time of crown delivery (ARP/DP: 9.6 vs. EP: 9.1, p = .02).

CONCLUSIONS

EP and ARP/DP show no significant differences in buccal contour changes, aesthetics and patient-reported outcomes. However, ARP/DP is an easier procedure at all stages of the surgery compared to EP and could therefore be the preferred therapy for less experienced clinicians.