Soft and hard tissue evaluation of guided socket shield implant cases

BACKGROUND

The socket-shield (SS) technique results in long-term functional osseo- and dento-integration, preserving the dimensional stability of hard and soft tissues over time. This study aimed to describe the successful implementation of a surgical technique to facilitate "SS" cases.

METHODS

The cases included males and females aged 32-81 years consecutively treated between 2020 and 2023 (longest follow-up, 3.5 years). For each case, pre- and post-operative cone-beam computed tomography (Digital Imaging and Communications in Medicine files) and intraoral optical scans (IOS; STL files) were performed. Digital immediate implant placement and simultaneous tooth extraction and SS production were planned using an implant planning software. Implants were planned considering sagittal-ridge and tooth-root angular-configuration. Surgical guides were used to perform the digitally-supported SS technique. All cases were planned and surgically performed by one operator (Pedro M. Trejo). Preoperative digital IOS-models were superimposed to post-operative models to assess soft-tissue changes. Pre and post sagittal views were used to assess the radiographic buccal-plate thickness at various healing times. An investigator not involved with case planning or treatment performed measurements.

RESULTS

Results reflected soft-tissue stability with minimal mean thickness change at 0-, 1-, 2-, and 3-mm measurement levels of 0.03, -0.2, 0.14, -0.07, and 0.04 mm, respectively, with a mean gingival-margin change of 0.04 mm. The free gingival-margin change ranged from a 0.58-mm gain in height to a -0.57-mm loss. The mean radiographic buccal-plate thickness post-operatively was 2.04 mm (range, 0.7-2.9 mm).

CONCLUSION

The digitally-supported guided SS technique enables predictable immediate implant-placement positions and stable buccal peri-implant soft and hard tissues over time.

KEY POINTS

Why are these cases new information? The uniqueness of the surgical technique described herein is that it results in favorable positions of immediate, socket-shielded (SSed), implant placements, with soft- and hard-tissue stability as the byproduct. What are the keys to successful management of these cases? Digitally, plan for the best possible implant position within the alveolar housing to satisfy prosthetic requirements, and then adjust this position to accommodate the socket shield dimensions. Digitally, provide a space/gap between the future dentinal shield and the implant. Clinically, allow for time to carve the final position and dimensions of the shield. Plan ahead the extent of the apical third of the SS, and the removal of the apex, if dealing with a long root. What are the primary limitations to success in these cases? Inadequate use of digital technology; case-sensitive technique requires proper execution of each digital and technical clinical step.

Finite element analysis of stress distribution on residual root structure in socket shield procedure following immediate dental implant placement: an in vitro study

BACKGROUND

The success of implants in the socket shield technique relies on stress experienced by root fragments within the socket. Although there is no consensus on optimal root fragment thickness, varying thicknesses and dynamic implant placement induce stress in various directions and degrees. This study aimed to assess biomechanical response and stress distribution across different root fragment thicknesses in the socket shield procedure.

METHODS

This in vitro study was conducted to assess and compare the stress distribution on residual root structures of varying thicknesses positioned within the labial aspect of the maxillary incisor socket during immediate implant placement of standard dimensions. The procedure involved applying an insertional torque of 40 Ncm, and the analysis was conducted using finite element analysis software.

RESULTS

Utilizing the Numerical Technique with Abaqus software for explicit dynamics, von Mises stress and principal strain were analyzed on the root structure and bone under nonlinear contact conditions during implant torque application. For Model A, a loading torque of 40 Ncm was applied vertically on the implant, along with a horizontal force of 20 N on the root structure and bone. Results indicated maximum stress of 12.68 MPa on the root structure with a thickness of 0.5 mm and 5.61 MPa on the bone, with principal strains of 6.82E-03 and 4.10E-03, respectively. In Model B, with a root structure thickness of 1.0 mm, the maximum stress increased to 19.70 MPa, while the bone stress rose to 9.51 MPa, with principal strains of 1.03E-02 and 6.09E-03. Model C, with a root structure thickness of 1.5 mm, exhibited a maximum stress of 21.58 MPa on the root and 10.12 MPa on the bone, with principal strains of 1.16E-02 and 6.10E-03. Lastly, in Model D, with a root structure thickness of 2.0 mm, the maximum stress on the root structure and bone escalated to 28.74 MPa and 11.38 MPa, respectively, with principal strains of 1.55E-02 and 8.31E-03.

CONCLUSIONS

As the thickness of the shield increases (ranging from 0.5 to 2 mm) in socket shield procedures with immediate implant placement, both stress on the root fragment and bone and principal micro-strain escalate. However, employing a shield thickness within the range of 0.5 to 2 mm does not lead to any adverse stress generation on the residual root fragment. However, for enhanced safety, it is recommended to restrict the maximum diameter and extension of the root fragment to 1.5 mm when considering implant sizes and socket diameter for the socket shield technique.

Five-Year Clinical, Radiographic, and Cone-Beam Follow-Up of Socket Shield Technique in Two Cases Treated with a Split Mouth Design

The two presented cases of socket shield technique were done following a split mouth protocol in two patients, each received an immediate implant inserted conventionally on maxillary one side and another implant inserted applying the socket shield technique on the contralateral side. The outcomes including soft and hard tissue changes were compared clinically and radiographically. The four implants were followed for 5 years, and the outcomes were successful.

Effect of CAD/CAM Guide Plate Combined With Socket-Shield Technique in Immediate Implantation of Anterior Teeth Aesthetic Area and Its Influence on Aesthetics

Purpose

The purpose of this study is to discuss the effect of computer-aided design or computer-aided manufacturing (CAD/CAM) guide plate combined with socket-shield technique (SST) in immediate implantation of anterior teeth aesthetic area and its influence on aesthetics.

Methods

A total of 102 patients with immediate implantation in our hospital from March 2017 to March 2020 were selected. According to different repair methods, patients were divided into conventional group (n = 51) and observation group (n = 51). Traditional immediate implantation was performed in conventional group. The observation group underwent immediate implantation with CAD/CAM guides combined with SST. Immediately after operation and 12 months after operation, the success rate, implant deviation, periodontal index, absorption of labial bone plate, complications, aesthetic effects, and satisfaction of the two groups were observed.

Results

There was no significant difference in the success rate between the two groups (p > 0.05). The implant deviation values in the observation group were all lower than those in the conventional group (p < 0.05). PD, PLI, and SBI in the observation group were all lower than those in the conventional group (p < 0.05). The absorption value of labial bone plate in the observation group were all lower than those in the conventional group (p < 0.05). The total incidence of complications in the observation group (5.88%) was lower than that in the conventional group (19.61%) (p < 0.05). The PES and WES in the observation group were higher than those in the conventional group (p < 0.05). The total satisfaction in the observation group (92.16%) was higher than that in the conventional group (76.47%) (p < 0.05).

Conclusion

: The application of CAD/CAM guide plate combined with SST in immediate implantation of anterior teeth aesthetic area has a good effect, which can improve the accuracy of implantation, improve the periodontal environment, reduce bone resorption, reduce complications, improve aesthetics, and have high patient's satisfaction.

Navigation guided socket-shield technique for implant and pontic sites in the esthetic zone: A proof-of-concept 1-year prospective study with immediate implant placement and loading

OBJECTIVE

To assess clinical, radiological performance of novel navigation guided socket-shield technique (NSS) with immediate implant placement and loading.

MATERIALS AND METHODS

Eighteen patients (12 females; age 52.54 ± 4.92; 33-72) treated between January 2018 and June 2019, were investigated, and followed for at least 1 year after definitive prosthesis placement (mean 20.1 months, 18-23). Primary outcomes: implant and prosthetic success rates, surgical, biologic, prosthetic complications.

SECONDARY OUTCOMES

marginal bone loss (MBL), implant stability quotient (ISQ), pink esthetic score (PES), plaque and bleeding indexes.

RESULTS

Sixty-nine navigation guided socket-shield procedures were performed (27 implant-sites and 42 pontic-sites) and 27 implants (NobelParallel, NobelBiocare AG) positioned and immediately loaded. Mean insertion torque and ISQ at implant positioning were 49 ± 5.34 Ncm (36-74), 73 ± 5.72 (68-81). No implant failure was experienced. Two root-shield exposures with mucositis, ulceration and bleeding were reported at two pontic-sites (2.9%) and successfully treated. No complications were experienced at implant-site leading to an overall NSS success-rate of 100%. No prosthetic complications occurred. Mean MBL was -0.72 ± 0.26 mm (-0.42 to -1.06 mm). PES final at the last follow-up 12.84 ± 0.92. The plaque and bleeding scores were 18.5 ± 6.12 and 3.15 ± 2.21.

CONCLUSIONS

Within study limitations, dynamic navigation was effective to streamline execution of socket-shield technique at implant and pontic sites, shortening treatment time and reducing complications. Navigation guided socket-shield technique was reliable to achieve digitally planned shield-to-implant distance, facilitate immediate implant placement and loading and establish the mucosal dimension needed for underlying bone-to-implant protection and esthetic integration.

CLINICAL SIGNIFICANCE

The investigated NSS technique overcomes the difficulties related to root preparation at implant and pontic-sites, facilitating immediate implant placement and loading. Dynamic guided surgery contributed to make socket-shield technique less technical-sensitive, shortening time for execution, reducing complication rate.

The socket shield technique for immediate implant placement: A systematic review and meta-analysis

BACKGROUND

Immediate implant placement with socket shield technique (SST) may maintain the buccal bone plate and soft tissue levels, however, the potential clinical benefits of SST lack strong scientific evidence. The aim of this systematic review and meta-analysis was to evaluate the effects of SST on dimensional changes of hard tissues, esthetic outcomes, implant stability, complication, and implant failure rates.

METHODS

Electronic databases were searched to identify randomized controlled trials (RCTs) that compared immediate implant placement with and without SST. The risk of bias was assessed using the Cochrane Collaboration's Risk of Bias tool. Data were analyzed using a statistical software program.

RESULTS

A total of 982 studies were identified, of which, seven RCTs with 206 immediately placed dental implants in 191 participants were included. Overall meta-analysis showed significant differences in the changes in buccal bone plate width (mean difference (MD) -0.22; 95% confidence interval (CI) -0.30 to -0.15; p < 0.0001) and height (MD -0.52; 95% CI -0.85 to -0.18; p = 0.002) in favor of SST. The use of SST was also associated with significantly less changes in peri-implant marginal bone levels and better pink esthetic score than immediately placing implants without SST. The differences in implant stability, complication and implant failure rates were not statistically significant between immediate implant placement with or without SST.

CONCLUSIONS

The short-term complication and implant failure rates following immediate implant placement with or without SST were comparable. The SST has short-term positive effects on the changes in width and height of buccal bone plate, peri-implant marginal bone levels and esthetic outcomes. Further evidence from long-term RCTs are still required to substantiate the current findings.

CLINICAL SIGNIFICANCE

SST can reduce changes in buccal plate width and height and improve the soft tissue profile following immediate implant placement in esthetic zone.

Failure Rate, Marginal Bone Loss, and Pink Esthetic with Socket-Shield Technique for Immediate Dental Implant Placement in the Esthetic Zone. A Systematic Review and Meta-Analysis

Aim: To compare the failure rate, marginal bone loss, and pink esthetic for the socket-shield technique and the conventional technique for immediate dental implant placement in the esthetic zone. Material and methods: A systematic literature review and meta-analysis, based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) recommendations, of clinical studies that evaluated the failure rate, marginal bone loss, and pink esthetic with the socket-shield technique for immediate dental implant placement in the esthetic zone was performed. A total of 4 databases were consulted in the literature search: PubMed-MEDLINE, Scopus, Embase, and Web of Science. After eliminating duplicated articles and applying the inclusion criteria, 16 articles were selected for the qualitative and quantitative analysis. Results: Four randomized controlled trials, five prospective clinical studies, four retrospective studies, and three case series were included in the meta-analysis. The dental implant failure rate for the socket-shield technique for immediate dental implant placement was 1.37% (95% CI, 0.21-2.54%); however, no statistically significant differences between the conventional and socket-shield technique were found. The estimated mean difference in the marginal bone loss for the socket-shield technique was -0.5 mm (95% CI, -0.82 to -0.18) and statistically significant (p < 0.01), with a high heterogeneity (I² = 99%). The mean pink esthetic score was 12.27 (Q test = 4.47; p-value = 0.61; I² = 0%). The difference in pink esthetic between the conventional (n = 55) and socket-shield techniques (n = 55) for immediate dental implant placement was 1.15 (95% CI, 0.73-1.58; Q test = 8.88; p value = 0.11; I² = 44%). The follow-up time was found to be significant (beta coefficient = 0.023; R² = 85.6%; QM = 3.82; p = 0.049) for the PES for the socket-shield technique. Conclusions: Within the limitations of this systematic review with meta-analysis, the dental implant failure rate did not differ between the socket-shield technique and conventional technique for immediate implant placement in the esthetic zone. However, a lower marginal bone loss and higher pink esthetic scores were found for the socket-shield technique compared to the conventional technique.

Comparison of the soft and hard peri-implant tissue dimensional changes around single immediate implants in the esthetic zone with socket shield technique versus using xenograft: A randomized controlled clinical trial

OBJECTIVE

Compare the dimensional changes of the peri-implant soft and hard tissues clinically and radiographically around single immediate implants in the esthetic zone with socket shield technique versus filling the buccal gap with xenograft.

MATERIALS AND METHODS

Forty-two patients with a single non-restorable tooth in the esthetic zone replaced with an immediate implant were randomly assigned either to the socket shield technique (test) or to grafting the buccal gap with xenograft (control). The vertical and horizontal buccal bone resorption were measured 6-months following implant placement. The esthetic outcomes were evaluated by assessing the Pink Esthetic Score (PES) and the amount of midfacial mucosal alteration, in addition to patient satisfaction assessment through a Visual Analogue Scale (VAS) based questionnaire 1-year following implant restoration.

RESULTS

The present study showed that the socket shield group yielded significantly less vertical and horizontal buccal bone resorption of 0.35 (±0.62) mm and 0.29 (±0.34) mm compared to 1.71 (±1.02) mm and 1.45 (±0.72) mm in the xenograft group respectively. Also, there was a significantly greater midfacial mucosal recession in the xenograft group of 0.466 (±0.58) mm compared to midfacial mucosal coronal migration of 0.45 (±0.75) mm in the socket shield group. However, there was no statistically significant difference regarding the total PES and patient satisfaction in both treatment groups.

CONCLUSION

The socket shield technique can preserve hard and soft peri-implant tissues following immediate implant placement. (ClinicalTrials.gov Identifier: NCT03684356).