The influence of implant placement depth on peri-implant tissues in immediate implant placement: A randomized controlled clinical trial with 1-year follow-up.
Jul 2026· Journal of Prosthodontics· Vol 35, pp. 1008-1020· 0 citations· 54 references
Medicine
TL;DR
Immediate implants placed 6 mm below the mid-buccal gingival level showed significantly less short-term marginal bone loss than immediate implants placed 4 mm below the gingiva after a period of 1 year.
Abstract
Purpose
This clinical trial was carried out to compare the outcomes of immediate implants positioned 4 mm below free gingival margin versus deeper placement of 6 mm after a period of 1 year.
Materials And Methods
Seventy platform-switching implants with a Morse taper conical connection and 1 mm of machined neck were placed in a flapless approach in the molar or premolar region immediately after tooth extraction. A total of 35 implants were positioned 4 mm below the buccal gingival margin (control group), and another 35 were placed 6 mm below the gingival margin (test group). All implant sites were grafted with an allogenic bone substitute and received individual healing abutments (IHAs) made chairside. After 4 months, the implants were restored with final screw-retained zirconia restorations. Radiographic marginal bone loss (MBL) was measured at the delivery of the final restoration (T1) and after 1 year (T2). Peri-implant clinical parameters (probing depth [PD], bleeding on probing [BOP], and plaque index [PI]) were recorded at 1-year follow-up appointment (T2).
Results
In total, 70 implants were evaluated after 1 year of follow-up (35 control and 35 test groups). The test group showed significantly lower (p < 0.001) MBL than the control group at both T1 (mean ± standard deviation: 0.11 ± 0.32 vs. 0.76 ± 0.68 mm) and T2 (0.12 ± 0.23 vs. 0.54 ± 0.49 mm). The PD mean was 3.46 ± 0.74 in the control group and 3.49 ± 1.20 in the test group, with a p-value of 0.890. PI and BOP were also similar in both groups: PI-11% for the control and 8% for the test groups (p = 0.551), BOP-13% for the control and 7% for the test groups (p = 0.214).
Conclusions
Immediate implants placed 6 mm below the mid-buccal gingival level showed significantly less short-term (up to 1 year) MBL than immediate implants placed 4 mm below the gingiva.
Objectives To compare 12-month marginal bone loss (MBL) between immediate implant placement (IIP) and early implant placement (EIP) in the anterior region. Secondary objectives included the evaluation of implant stability (ISQ), esthetic outcomes (PES–WES), and peri-implant health (probing depth and bleeding index) when using customized healing abutments. Methods A prospective, randomized, split-mouth clinical trial was conducted involving 12 patients, with a total of 24 implant sites. The protocol was approved by the institutional review board (IRB2023-H0113D-P-0494), registered at ClinicalTrials.gov (NCT0698551). Each patient received one IIP and one contralateral EIP via fully guided surgery. Chairside-fabricated customized healing abutments were utilized, and definitive restorations were delivered at 3 months. Outcomes were recorded at 3, 6, and 12 months. MBL was assessed via standardized CBCT, implant stability via resonance-frequency analysis, and esthetics through Pink/White Esthetic Scores. Mixed-effects models were used for statistical analysis (α = 0.05). Results IIP demonstrated significantly lower early MBL at 3 months (mean difference: −0.30 mm, 95% CI: −0.52 to −0.08; p = 0.012) and 6 months (mean difference: −0.22 mm, 95% CI: −0.39 to −0.05; p = 0.016), and higher ISQ at 3 months (mean difference: 2.49, 95% CI: 0.49–4.49; p = 0.017) compared to EIP. However, no significant differences were observed in MBL (mean difference: −0.01 mm, 95% CI: −0.08 to 0.06; p = 0.618) or ISQ (mean difference: 0.20, 95% CI: −1.62 to 2.02; p = 0.823) at the 12-month primary endpoint. Regarding esthetics, total PES favored IIP at 6 months (mean difference: 2.09, 95% CI: 1.48–2.70; p < 0.001) and 12 months (mean difference: 1.50, 95% CI: 0.92–2.08; p < 0.001). WES was similar at 6 months (mean difference: 0.42, 95% CI: −0.31 to 1.15; p = 0.234) but favored IIP at 12 months (mean difference: 1.00, 95% CI: 0.50–1.50; p = 0.002). Peri-implant health parameters improved over time in both groups with no implant losses. Conclusions When combined with guided protocols and customized healing abutments, IIP and EIP yield comparable 12-month marginal bone outcomes. IIP provides an advantage in accelerated early stability and superior soft-tissue esthetic scores (PES) compared to EIP. The clinically meaningful esthetic advantages of IIP support its preferential use in the anterior zone when anatomical conditions permit.
S. E. El Touliani, Ahmed M. Abdel-Hamid, Nada M. Fahmy et al.· Frontiers in Dental Medicine· 0 citations
To evaluate crestal bone level changes and survival of immediately placed extra-wide diameter implants in posterior molar sites.
This prospective clinical study included 30 patients requiring molar extraction and implant placement, with 28 patients completing follow-up. A total of 29 implants were placed immediately following atraumatic extraction and positioned subcrestally. Crestal bone levels were measured radiographically at placement and at a minimum of 1-year post-restoration using calibrated ImageJ analysis.
The mean crestal bone level was 1.28 mm at placement and 0.46 mm at follow-up, with a mean change of 0.82 mm (95% confidence intervals: 0.34–1.29 mm). This difference was statistically significant (
p
= 0.001). Despite this change, crestal bone levels remained coronal to the implant platform at follow-up. One implant failure occurred, resulting in a survival rate of 96.5%.
Immediate placement of extra-wide diameter implants in posterior molar sites demonstrated high survival rates and maintenance of crestal bone levels above the implant platform, suggesting this approach is a predictable treatment option.
Katherine Sue Hanser, D. Miley, Robert L. Blackwell et al.· Journal of Advances in Denta...· 0 citations
Background: The immediate placement of implants after the extraction of non-salvageable teeth results in shorter treatment durations and enhanced patient satisfaction. However, placing implants in the posterior region of the mandible poses difficulties due to the quality of the bone and its closeness to the mandibular canal. Case Presentation: A 45-year-old male patient arrived with a vertically fractured mandibular second molar (tooth #36) deemed hopeless due to vertical bone loss, root fracture, and being endodontically non-restorable. After performing an atraumatic extraction and socket debridement, a titanium implant measuring 6 (cid:2) 10 mm was inserted with an insertion torque of 45 Ncm. Outcomes: At 6-month follow-up, radiographic evaluation revealed stable marginal bone levels (0.4 mm loss), healthy peri-implant soft tissue, and satisfied occlusion. No complications occurred. Conclusion: Immediate placement of implants in the posterior region of the mandible is achievable when sufficient bone height (greater than 10 mm) and primary stability (exceeding 35 Ncm) are attained. The processes of socket grafting and atraumatic extraction are essential for achieving successful results in cases involving hopeless teeth.
Manveer Singh, Tarun Kalra1, Manjit Kumar· International Journal of Ora...· 0 citations
The Bone Ring Technique (BRT) is a newer viable option for restoring complex defects around dental implants with three-dimensional bone augmentation with significant height and width augmentation of buccal bone.
Priyadharshini Annamalai Senthur Pandian, Aniz Amanullah, Lakshmiganthan Mahalingam et al.· Journal of Clinical and Diag...· 0 citations
Background and Clinical Significance: Immediate implant placement in mandibular molars represents a clinical challenge due to lower trabecular bone density and anatomical limitations of the interradicular septum. Osseodensification has been proposed as an alternative to improve primary stability in sites with low bone quality. Case Presentation: This report describes the case of a 54-year-old female patient with a mesial root fracture in the lower right first molar, treated by atraumatic extraction followed by immediate implant placement using a densifying drilling protocol. After careful root removal, the interradicular septum was expanded using Versah burs at 1200 rpm, allowing placement of a 4.0 × 7 mm Implacil Duecone implant with a final insertion torque of 25 Ncm. The residual gap was filled with a xenogeneic bone substitute and covered with a dense polytetrafluorethylene membrane for alveolar preservation. Healing progressed uneventfully and, after four months, adequate bone formation was observed, enabling prosthetic rehabilitation with a single ceramic crown. After 4 postoperative years we could find peri-implant tissue stability. Conclusions: The clinical outcome supports current evidence indicating that osseodensification may enhance initial stability and predictability of immediate implants placed in posterior mandibular regions.
Márcio de Carvalho Formiga, Jucielly Santos Lesnik de Souza, Gustavo Dos Santos Coura et al.· Reports· 0 citations
The aim of this clinical trial was to compare the implant stability in terms of primary and secondary stability with three different osteotomy techniques, to establish a protocol that can consistently help achieve increased implant stability in the maxillary posterior region. A total of 30 patients (19 males, 11 females; mean age 46.3 ± 8.7 years) requiring single implant placement in the maxillary posterior region were divided into three groups. Endosseous implants (Straumann Bone Level Tapered, SLActive surface, 4 mm × 10 mm) were placed in Group I using conventional osteotomy, Group II with Summers’ osteotome technique, and Group III with the osseodensification technique. All implants were placed with an emerged (non-submerged) technique and immediately restored with provisional prostheses adjusted to eliminate centric and eccentric contacts (immediate restoration without functional loading). The stability was assessed at the time of implant placement, at three months and at six months using resonance frequency analysis (Osstell). One-way ANOVA and Tukey post-hoc test were used to compare the ISQ values between groups, and repeated measures ANOVA for intragroup comparisons. No statistically significant differences were observed in the ISQ values at the time of placement, three months, and six months after implant placement between Group I (Conventional osteotomy), Group II (Summers’ osteotome technique), and Group III (Osseodensification). However, numerical trends indicated slightly lower initial primary stability in Group II and slightly higher values in Group III throughout the observation period. All implants achieved 100% survival at six months. Within the limitations of this exploratory study, all three osteotomy techniques achieved adequate primary stability for immediate restoration in the maxillary posterior region. While no statistically significant differences were detected between techniques, numerical trends suggest that osseodensification may offer marginally better primary stability and Summers’ osteotome technique showed slightly lower initial values. These findings should be interpreted cautiously given the small sample size and relatively short follow-up period. Further large-scale, adequately powered studies are needed to definitively establish clinical superiority of any technique. CLINICAL TRIAL REGISTRY OF INDIA (CTRIICMR) REGISTRATION NO. CTRI/2021/09/036513. Registered retrospectively on 15/09/2021 (enrollment began September 2020). Available at https://www.ctri.nic.in.
N. Venkatesh, M. Shetty, C. Hegde et al.· BMC Oral Health· 1 citation· ⚡1