Clinical evaluation of the buccal aspect around immediate implant using dual zone therapeutic concept versus buccal gap fill to bone level: A randomized controlled clinical trial

Evaluation of the Effectiveness of the Dual-Zone Bone Grafting Technique in Immediate Implant-Immediate Restorations

BACKGROUND

The traditional immediate implant technique may lead to massive resorption of the labial bone plate.

PURPOSE

To study the evaluation of the dual-zone bone grafting technique for hard and soft tissue stability and aesthetic results in immediate implant-immediate restoration cases when faced with cases with thin labial bone plates.

STUDY DESIGN, SETTING, SAMPLE

This study selected 60 cases of labial bone plate and compared the dual-zone bone graft technique with the traditional immediate implant technique at Tianjin Stomatological Hospital from January 2018 to January 2023. CBCT was performed preoperatively, immediately postoperatively, 5 months postoperatively, and 1 year after the final restoration was completed, and intraoral retention was performed.

PREDICTOR

Bone resorption;labial-lingual width.

MAIN OUTCOME VARIABLE

(1) Short-term retention rate of implants. (2) Pathologic movement. (3) Bone resorption. (4) Labial-lingual width. (5) Red aesthetic index score.

COVARIATES

Gingival biotype; types of bone powder.

ANALYSIS

The dual-zone bone grafting technique can effectively maintain the stability of bone powder, promote bone formation and delay bone resorption.

RESULTS

(1) The short-term retention rate of implants was 100%. (2) The implants were stable and there was no pathological movement. (3) The amount of bone resorption in the dual-zone group was less than the traditional group after surgery. (4) The change in labial-lingual width in the dual-zone group was small. (5) The red aesthetic index score in the dual-zone group was higher than that in the traditional group. (6) The dual-zone group had better preservation of plaque index and gingival papilla.

CONCLUSIONS AND RELEVANCE

The dual-zone bone graft technique has more advantages in immediate implant placement and restoration.

Evaluation of buccal bone resorption in immediate implant placement in thin versus thick buccal bone plates: An 18-month follow-up prospective cohort study

OBJECTIVES

The current guidelines recommend that immediate implants be placed in patients with thick (>1 mm) buccal bone due to the inevitable tissue remodeling that follows tooth extraction. The aim of the current study was to investigate the effect of buccal bone thickness on bone resorption in immediate implant placement and compare two measuring techniques of the aforementioned resorption.

MATERIALS

The present study was designed as a prospective nonrandomized, controlled clinical trial. A total of 30 implants were split between the two study arms, thin buccal bone and thick buccal bone. The primary outcome was to assess vertical bone changes radiographically by cone beam scans preoperatively, at 2 months and 18 months after implant placement in patients with thin and thick buccal plate. Secondary outcomes included the change in the thickness of the buccal bony plate, marginal bone loss, and pink esthetic score.

RESULTS

Only 26 implants were statistically analyzed as one early failure was observed in each group. Furthermore, 2 patients of the thick group withdrew from the study. Cone beam computed tomography measurements revealed that at 2 months the vertical bone loss was 1.09 for the thin group and 0.85 for the thick group. The buccal bone plate resorption of the thin group was 0.39 mm while it was 0.52 mm for the thick group. The buccal bone plate was 1.25 mm in the thin group and 1.88 mm in the thick group. The PES did not show any significant difference with very good esthetic results.

CONCLUSION

Within the limitations of the current study, the amount of buccal bone plate resorption and the subsequent thickness obtained after implantation in both groups suggest successful long-term results. The two measuring techniques have proven to be comparable and reliable in the measurement of buccal bony plate changes. https://classic.

CLINICALTRIALS

gov/ct2/results?cond=&term=NCT04731545&cntry=EG&state=&city=&dist=.

Hard and soft tissue alterations using dual-zone concept versus connective tissue graft at maxillary immediate implant placement: A 1-year randomized clinical and volumetric trial

OBJECTIVES

To evaluate the esthetic outcome, as well as clinical, radiographic, and volumetric tissue alterations 1 year after immediate implant placement (IIP) with connective tissue grafting (CTG) versus dual-zone concept (DZ) at sites with thin labial bone in the esthetic zone.

MATERIALS AND METHODS

This randomized clinical trial included 30 patients treated with IIP simultaneous with either CTG or DZ (n = 15 each). Pink esthetic score (PES) was assessed 6 months after crown placement as the primary outcome. Amount of bone labial to the implant, labio-palatal ridge reduction, and crestal bone changes were measured via CBCT after 1 year. Volumetric analysis of linear labial soft tissue contour, interdental, and mid-facial soft tissue level changes, and total volume loss (mm3) were measured after 1 year.

RESULTS

Similar PES was observed in the CTG (12.53 ± 1.13) and DZ (12.13 ± 1.55) groups, with no significant difference (p = 0.42). Likewise, there were no statistically significant differences found between the two groups in labio-palatal bone reduction (mm&%), interdental papillae, and mid-facial gingival levels (p > 0.05). However, the mean vertical crestal bone changes in the CTG and DZ groups were -1.1 ± 0.6 mm and 0.2 ± 1.0 mm, respectively, with a statistically significant difference (p = 0.0002). Moreover, CTG revealed less linear and total volume (mm3) loss in the labial soft tissue which was statistically significant compared to DZ (p = 0.007).

CONCLUSION

Both groups demonstrated the same PES, nevertheless, volumetric analysis revealed twice total labial volume loss in DZ compared to CTG. It might be concluded that the use of CTG with IIP caused less horizontal reduction in the supra-implant complex compared to the DZ.

The bone shielding versus dual-zone concept in treating thin-walled fresh extraction sockets with immediate implant placement: Soft and hard tissue changes. A randomized clinical trial

OBJECTIVES

To evaluate the ridge alterations and esthetic outcome 1 year after immediate implant placement using the dual-zone (DZ) technique versus the bone shielding concept in patients with intact thin-walled sockets in the esthetic zone.

MATERIAL AND METHODS

This randomized clinical trial included 26 patients with nonrestorable maxillary teeth in the esthetic zone who were randomly assigned to two groups (n = 13 each) to receive immediate implants using either the bone shielding concept or DZ. Definitive restorations were delivered after 2 months. Pink esthetic scores (PESs), vertical soft tissue alterations, and bucco-palatal ridge dimensional changes were measured and assessed using intra-oral digital scans at baseline and 1 year post-procedure. Labial bone thickness was measured using cone beam computed tomography scans at baseline and after 1 year.

RESULTS

The bone shielding group provided bucco-palatal ridge thickness stability after 1 year (9.43 mm) compared to baseline values (9.82 mm), while DZ showed a significant loss in the bucco-palatal ridge thickness after 1 year (7.83) compared to baseline values (9.49). No significant difference was reported in the baseline bucco-palatal ridge thickness between the two groups (p = 0.6). After 1 year, the bone shielding group demonstrated 0.38 mm ridge shrinkage which was statistically significant (p = 0.0002) compared to 1.67 mm ridge shrinkage in the DZ group. In addition, the average total PES in the bone shielding group was 12.04 versus 10.28 in the DZ group. No significant difference was reported in the mesial papilla length between the DZ and the bone shielding group after 1 year (p > 0.05). However, the midfacial gingival margin (p = 0.026) and distal papilla were significantly higher in the DZ group (p = 0.0025). There was no significant difference in the mean ± SD mm bone gain at the apical level between the two studied groups after 1 year (p = 0.06) showing 0.85 ± 0.23 and 0.64 ± 0.32 mm, respectively. However, the bone shielding concept showed a statistically significant more bone gain mm (p < 0.001) at the (0.56 ± 0.43) and crestal (0.03 ± 0.8) levels after 1 year compared to DZ which revealed 0.18 ± 0.5 and 0.38 ± 0.29 mm bone loss, respectively.

CONCLUSION

The bone shielding concept might offer a reliable alternative for restoring thin-walled sockets by minimizing postextraction ridge dimensional alterations effect following immediate implant placement in the esthetic zone. Nevertheless, the study suffers from confounding bias since there are two systematic differences between the groups, the barrier membrane type, and the level of bone filling. "This clinical trial was not registered prior to participant recruitment and randomization."

CLINICAL TRIAL REGISTRATION

NCT05381467.

The Use of Tissue Grafts Associated with Immediate Implant Placement to Achieve Better Peri-Implant Stability and Efficacy: A Systematic Review and Meta-Analysis

Background: The goal of this systematic study and meta-analysis was to evaluate the efficacy of hard and/or soft tissue grafts associated with type-1 implants on healing and treatment outcomes. The primary outcomes studied were implant survival rate, pocket depth, marginal peri-implant recession, bone loss, bone thickness (volumetric change), interproximal bone level, mesial and distal papilla migration, and radiographic evaluation; and the secondary parameters were Pink Esthetic Score (PES), vertical distance from implant shoulder and bone, Visual Analogue Score (VAS), Implant Stability Quotient (ISQ), and biological complications (fistulas, pain, mucositis, and peri-implantitis). Methods: The PICO strategy was used to formulate the hypothesis under study: "For patients who underwent extraction and immediate implant placement, what is the efficacy of using any type of graft (bone or soft tissue) compared to non-grafting regarding the peri-implant parameters?" The electronic search process was performed on the MedLine/PubMed and Cochrane databases. It included randomized controlled trials (RCTs) from the last 11 years (from 2012 to November 2023), which were identified and analyzed. Results: Nine RCTs (κ = 0.98) were selected (403 patients and 425 implants); they were divided into three groups: bone graft (75 patients and 75 implants inserted), bone graft and membrane (213 patients and 235 implants inserted), and without bone graft (115 patients and 115 implants inserted). Three studies calculated the mid-facial mucosa level and two reported better results when a connective tissue graft was combined with the xenograft, whereas another study found better results in the combination of a dual-zone technique with a xenograft. Three studies evaluated the total Pink Esthetic Score (PES) at 12 months, where the authors found no significant difference in using a xenogeneic graft with or without a membrane. In the same period, the facial bone thickness was assessed in two articles; the authors reported better results in graft-treated and flapless groups. The risk-of-bias assessment found four studies with low risk, four with moderate risk, and one with a high risk of bias. The meta-analysis showed a medium level of heterogeneity for the mid-facial mucosa level analysis (I2 = 46%) and an overall effect size of 0.79 (95% CI [0.18; 1.40]), a statistically significant results (p = 0.01), with a tendency to favor the experimental group. Also, there was a medium level of heterogeneity among studies regarding total PES (I2 = 45%), with no significant differences between studies (p = 0.91). Homogeneous results (I2 = 0%) were found among studies analyzing facial bone thickness, favoring the experimental group; the forest plot showed an effect of 0.37 (95% CI [0.25; 0.50]), which was statistically significant (p < 0.00001) for this parameter. Conclusions: Then, it was possible to conclude that using bone and soft tissue grafting techniques associated with immediate implant placement (IIP), even though they are not fundamental, was a valuable resource to prevent significant tissue reduction, reaching greater bone stability and higher levels in the Pink Esthetic Score (PES) and Visual Analogue Score (VAS).

The peri-implant mucosa color: A systematic appraisal of methods for its assessment and clinical significance

BACKGROUND

Peri-implant mucosa color (PMC) seems to be one of the main parameters affecting the esthetic outcome of implant therapy. However, more emphasis should be given to its assessment and reporting.

PURPOSE

To describe the available evidence on methods to assess and report the color of the peri-implant mucosa (PMC) and the respective clinical relevance.

MATERIAL AND METHODS

A comprehensive electronic and manual search was performed to identify clinical studies reporting on PMC.

RESULTS

A total of 121 studies were included. PMC was evaluated at the time of the follow-up visit (chairside) in 45.5% studies. PMC assessment was performed qualitatively, by comparing PMC with adjacent and/or contralateral gingiva (78.6%) or quantitatively, using spectrophotometry (20.7%) or a software on clinical photographs (0.8%). The most performed method to assess PMC was through esthetic indices (76.9%), either at the time of the follow-up visit (chairside) or at later time point using photographs. Quantitative reporting of PMC included averages of points from esthetic indices or color differences to natural gingiva expressed with the CIELAB color system. PMC assessment allowed describing color discrepancies compared to natural gingiva, evaluating color changes over time, and comparing the outcomes of different treatment modalities. PMC assessment through spectrophotometry was additionally utilized to assess the role of mucosal thickness (MT) on PMC.

CONCLUSIONS

Various methods for PMC assessment and reporting were described, including visual assessment, mainly through esthetic indices, and spectrophotometry. PMC evaluation has allowed to demonstrate the factors affecting the color of the peri-implant soft tissue, such as the type of abutment/restoration, MT, and soft tissue augmentation.