Dental implants inserted in fresh extraction sockets versus healed sites: A systematic review and meta-analysis

Five- and 18-Year Outcome of Two Cases with Full-Arch Rehabilitations Ad modum All-on-4 in the Presence of Challenging Conditions

Placing implants in fresh postextraction sites is a borderline rehabilitation procedure. The purpose of this report is to describe the pre-, per-, and postoperative procedures for maintaining long-term stability of two full-arch rehabilitations through the All-on-4 protocol, performed in the presence of challenging conditions. Two patients were referred for full-arch rehabilitation with immediate function, with both patients presenting infection in the jaws: patient 1 with an implant (position #45) inserted in a cystic cavity; patient 2 with one implant (position #24) inserted transsinus after the removal of a cyst on the base of the maxillary sinus and another implant (position #15) inserted with a dehiscence. Both patients received a preoperative dental hygiene appointment, a regenerative surgical protocol, and were enrolled in a postoperative maintenance protocol. After surgery a provisional prosthesis was provided ensuring immediate function, and 6 months after surgery, the final prosthesis was delivered. During the follow-up appointments (final follow-up at 5 and 18 years), the implants were stable, and no infection was observed for both patients. The present case report describes two full-arch rehabilitations in immediate function, supported by dental implants inserted in the presence of challenging conditions that do not represent the norm, rather are highly demanding for the clinical team, warranting caution in the interpretation of the results.

CAD-CAM custom healing abutments: A dental technique

Custom healing abutments are important in establishing optimal esthetics for prosthesis-driven, implant-supported restorations. This report demonstrates a technique for constructing a custom healing abutment with computer-aided design and computer-aided manufacturing to save chairside time and provide predictable results.

Transitioning From Teeth to Implants: A Narrative Review

PURPOSE

Patients may need removal of their teeth with placement of implants for rehabilitation. The clinical problem is the status of the remaining teeth and how this affects the timing for implant placement and the method for provisionalization. The importance of this review is to document the different strategies including sequential tooth removal and grafting and the use of teeth to provide a fixed provisional rather than a removable provisional, to provide surgeons with a reference to maintain patient function during their rehabilitation.

METHODS

Pubmed.gov was the information source. Years reviewed included 1990 to 2022. Inclusion criteria included only articles in peer-reviewed journals. Variables evaluated included the success for placing implants immediately into extraction sites, and the methods to transition between steps in their rehabilitation. Data collected were results of systematic reviews and independent clinical series, as well as case reports of prosthetic methods for transitioning.

RESULTS

The search used terms which included implants in extraction sites (n = 205) and transitioning teeth to implants (n = 153). Twenty-one articles were reviewed involving extraction sites and 19 articles reviewed concerning transitioning from teeth to implants. The placement of implants immediately into excretion sites did have a relative risk for failure compared to implant placement in healed sites. The use of non-restorable teeth to support a fixed provisional prosthesis was successful; however, variability in reporting prevented a statistical analysis.

CONCLUSION

The surgeon needs to utilize teeth to provide support during treatment phases in order to provide the patient with a fixed provisional prosthesis to allow for implant integration and to provide time for graft healing. Specific methods used for transitioning do not have a significant evidence base to recommend one method but routine prosthetic techniques have been used and are reported in case reports.

3D Printing of Ti-6Al-4V-Based Porous-Channel Dental Implants: Computational, Biomechanical, and Cytocompatibility Analyses

Objective: Loosening of dental implants due to resorption of the surrounding bone is one of the challenging clinical complications in prosthetic dentistry. Generally, stiffness mismatch between an implant and its surrounding bone is one of the major factors. In order to prevent such clinical consequences, it is essential to develop implants with customized stiffness. The present study investigates the computational and experimental biomechanical responses together with cytocompatibility studies of three-dimensional (3D)-printed Ti-6Al-4V-based porous dental implants with varied stiffness properties. Methods: Additive manufacturing (direct metal laser sintering, DMLS) was utilized to create Ti-6Al-4V implants having distinct porosities and pore sizes (650 and 1000 μm), along with a nonporous (solid) implant. To validate the compression testing of the constructed implants and to probe their biomechanical response, finite element models were employed. The cytocompatibility of the implants was assessed using MG-63 cells, in vitro. Results: Both X-ray microcomputed tomography (μ-CT) and scanning electron microscopy (SEM) studies illustrated the ability of DMLS to produce implants with the designed porosities. Biomechanical analysis results revealed that the porous implants had less stiffness and were suitable for providing the appropriate peri-implant bone strain. Although all of the manufactured implants demonstrated cell adhesion and proliferation, the porous implants in particular supported better bone cell growth and extracellular matrix deposition. Conclusions: 3D-printed porous implants showed tunable stiffness properties with clinical translational potential.

Differences in Dental Implant Survival between Immediate vs. Delayed Placement: A Systematic Review and Meta-Analysis

OBJECTIVES

To compare the impact of immediate and delayed implant placement upon the survival of implants and to investigate the differences in implant survival between immediate and delayed placement in adults.

METHODS

A search for the relevant literature was performed using the databases of CENTRAL, MEDLINE and Scopus. The studies found were limited to publications between 2014 and 2022, written in the English language, peer-reviewed, and were randomised trials or comparative studies. The quality of the evidence was assessed using the Cochrane Risk of Bias 2.0 and Risk of Bias in Non-randomised Studies-of Interventions appraisal tools and implant survival, and the primary outcome was meta-analysed using RevMan v.5.3.

RESULTS

A total of 10 studies were eligible for inclusion, including six randomised controlled trials and four non-randomised comparative studies. Five of the six randomised trials observed a low risk of bias, while the comparative studies had a moderate-to-serious risk of bias. The search strategy resulted in 341 implants placed immediately into fresh extraction sites (332 survived, 97.4%) and 359 implants inserted into delayed sites (350 survived, 97.5%).

CONCLUSION

The meta-analysis demonstrated that there was no significant difference in the implant survival rates between immediately placed implants and implants placed using a delayed timing protocol (risk ratio 0.99; 95% CI 0.96, 1.02, Z = 0.75, p = 0.45). However, the detailed analysis showed that slightly more implant failures happened in the immediate dental implant placement group, with survival rates in some studies ranging between 90 and 95%, while the delayed placement group had survival rates of more than 95%.

Human Histological Analysis of Early Bone Response to Immediately Loaded Narrow Dental Implants with Biphasic Calcium Phosphate® Grid-Blasted Surface Treatment: A Case Report

Implant surface topography using bioactive material provides faster bone-to-implant healing. This histological report described the analysis of human bone tissue around an immediately loaded implant, with BPC^® (Biphasic Calcium Phosphate) grit-blasted surface treatment, after two months of healing. Two temporary mini-implants (2.8 × 10 mm) with BPC^® grit-blasting surfaces were placed and immediately loaded to retain a complete interim denture. After a 60-day healing period, one mini-implant was removed for histologic analysis. The ground section showed the whole implant surrounded by healthy peri-implant tissues. Implant surface presented a close contact with newly formed bone, showing some areas of osteoblasts secreting mineral matrix. The ground section depicted a bone contact of 60.3 + 8.5%. The BPC^® grit-blasted surface was biocompatible and enabled the osseointegration process after a short-term period.

Outcomes of bio-esthetic single implant-supported restorations after peri-implant soft tissue conditioning with two prosthetic techniques: A 1-year randomized clinical trial

STATEMENT OF PROBLEM

Providing a definitive restoration with an emergence profile matching that of the contralateral or extracted tooth should result in an esthetic peri-implant soft tissue contour. Whether a custom healing abutment improves the outcome of a bio-copied definitive restoration compared with a stock abutment is unclear.

PURPOSE

The purpose of this 1-year randomized clinical trial was to evaluate the peri-implant soft and hard tissues related to bio-esthetic single implant-supported restorations having a contralateral tooth-matching restorative emergence profile after peri-implant soft tissue conditioning with either custom or stock healing abutment for patients indicated for immediate implant placement.

MATERIAL AND METHODS

Twenty-four participants indicated for immediate implant placement in the maxillary esthetic zone received bio-esthetic single implant-supported restorations after peri-implant soft tissue conditioning with either a custom healing abutment (n=12) or a stock healing abutment (n=12). The pink and white esthetic score (PES-WES) was evaluated 6 and 12 months after implant placement. Peri-implant bone changes were measured with cone beam computed tomography (CBCT) scans at the same intervals.

RESULTS

The PES-WES showed significant difference between the 2 groups at 6 and 12 months. The CBCT scans did not show significant difference between the 2 groups.

CONCLUSIONS

The use of the bio-esthetic concept for immediate single implant placement achieved successful esthetic restorations after conditioning the peri-implant tissues using either custom or stock healing abutments. However, the use of custom healing abutments was associated with higher PES-WES values in comparison with the use of stock healing abutments.

Buccal bone thickness assessment for immediate anterior dental implant planning: A pilot study comparing cone-beam computed tomography and 3D double-echo steady-state MRI

PURPOSE

To evaluate image quality and diagnostic accuracy of buccal bone thickness assessment in maxillary and mandibular anterior region using cone-beam computed tomography (CBCT) and 3-dimensional double-echo steady-state (DESS) MRI for preoperative planning of immediate dental implants in healthy individuals.

METHODS

One hundred and twenty teeth in 10 volunteers were retrospectively evaluated for image quality and artifacts using Likert scale (4 = excellent to 0 = decreased). Buccal bone thickness was measured at three measurement points (M1 = 2 mm from the cementoenamel junction, M2 = middle of the root, and M3 = at the root apex) for each tooth in the maxillary (13-23) and the mandibular anterior region (33-43). Descriptive statistics and two-way ANOVA with Tukey's Post-hoc test were performed to evaluate the significant differences (α = 0.05) between both imaging modalities.

RESULTS

Image quality showed little to no artifacts and enabled confident diagnostic interpretation (CBCT (3.72 ± 0.46); MRI (3.65 ± 0.49)), with no significant differences between both imaging modalities (p > 0.05). Regarding the assessment of buccal bone thickness at M1-M3 for the teeth 13-23 and 33-43, no significant differences were noted (p > 0.05). MRI demonstrated slight, nonsignificant overestimation of thickness with the canines having mainly a thick buccal bone wall, where thin buccal wall was evident for the central incisors.

CONCLUSION

Black bone MRI sequences, such as 3D-DESS MRI, for immediate implant planning provided confidential diagnostic accuracy in bone thickness assessment without significant disadvantages compared to CBCT. Thus, the implementation of no-dose protocols for dental rehabilitation using an immediate loading approach seems promising and could further improve the treatment strategy for dental rehabilitation.

A Retrospective Observational Study Assessing the Clinical Outcomes of a Novel Implant System with Low-Speed Site Preparation Protocol and Tri-Oval Implant Geometry

A novel, biologically friendly implant concept system introduces low-speed (50 rpm) site preparation instruments used without irrigation and a tri-oval, tapered implant designed to reduce stress on cortical bone without sacrificing mechanical stability. This retrospective, observational, multicenter study (clinicaltrials.gov NCT04736771) collected data from consecutive patients treated with at least one novel concept system implant to evaluate clinical outcomes after 1 year in function. The primary endpoint was a marginal bone level change (MBLC) from loading to 1 year, and secondary endpoints included implant survival and clinician feedback. Ninety-five patients (54 women and 41 men, mean age: 58 ± 12 years) were treated with 165 implants. For 94.5% of implants, site preparation was performed in two steps. The mean follow-up from implant insertion was 1.8 ± 0.2 years. Mean MBLC from implant loading to 1-year follow-up was +0.15 ± 0.85 mm (n = 124 implants). At the last follow-up, the implant survival rate was 98.0%. Clinician satisfaction with the novel concept system was high. The novel concept system offers an easy-to-use implant placement protocol, with most implants placed using two steps. The minimal bone remodeling and high survival rate observed across a variety of indications and treatment protocols demonstrate broad versatility and confirm the clinical benefits of this biologically friendly innovation.

Accuracy of additive manufacturing in stomatology

With the rapid development of the three-dimensional (3D) printing technology in recent decades, precise and personalized manufacturing has been achieved gradually, bringing benefit to biomedical application, especially stomatology clinical practice. So far, 3D printing has been widely applied to prosthodontics, orthodontics, and maxillofacial surgery procedures, realizing accurate, efficient operation processes and promising treatment outcomes. Although the printing accuracy has improved, further exploration is still needed. Herein, we summarized the various additive manufacturing techniques and their applications in dentistry while highlighting the importance of accuracy (precision and trueness).

Immediate implant placement utilizing vestibular socket therapy versus early implant placement with contour augmentation for rehabilitation of compromised extraction sockets in the esthetic zone: A randomized controlled clinical trial

OBJECTIVE

The present randomized controlled trial compares for the first time the vestibular socket therapy (VST) to the contour augmentation technique in the management of compromised fresh extraction sockets in the maxillary esthetic zone, regarding mid-facial soft tissue changes (primary outcome), mesial and distal papillae dimensions, horizontal soft tissue changes and labial bone plate thickness at apical, middle and coronal levels (secondary outcomes) over 1-year.

MATERIALS AND METHODS

Forty participants with single nonrestorable maxillary teeth in the esthetic zone were randomized into two groups; VST (test; n = 20) utilizing vestibular access for guided bone regeneration (GBR) with immediate implant placement, or contour augmentation (control; n = 20) undergoing an initial healing period followed by implant placement with GBR through a conventional access flap.

RESULTS

All implants were successfully osseo-integrated, except for one implant in the test group. VST showed significantly less mid-facial soft tissue changes of -0.53 ± 1.17 mm versus -1.87 ± 0.69 mm in the control group (p < 0.001). Similarly, changes in mesial papilla (test = -0.64 ± 0.95 mm, control = -1.20 ± 0.81 mm), distal papilla (test = -0.56 ± 1.17 mm, control = -1.26 ± 0.63 mm), horizontal soft-tissue (test = -0.82 ± 0.95 mm, control = -1.84 ± 0.88 mm; p < 0.05) were significantly less in VST. Intra-group comparisons demonstrated a significant increase in labial bone thickness, with no differences between groups. Regression analysis revealed a significant correlation between VST as well as increased coronal bone thickness with the reduction in mid-facial soft-tissue changes.

CONCLUSION

The VST showed less soft-tissue changes and could represent an innovative technique for implant placement in the maxillary esthetic zone. Both techniques showed a high implant survival rate and increased bone thickness after 12 months.

The Importance of Correlation between CBCT Analysis of Bone Density and Primary Stability When Choosing the Design of Dental Implants—Ex Vivo Study

This study aims to determine the correlation between the mean value of bone density measured on the CBCT device and the primary stability of dental implants determined by resonant frequency analysis. An experimental study was conducted on a material of animal origin: bovine femur and pig ribs. Two types of implants were used in this study: self-tapping and non-self-tapping of the same dimensions. Results of the experimental study showed a statistically significant correlation between bone density expressed in HU units and the primary stability of self-tapping and non-self- tapping dental implants expressed in ISQ units in bovine femur bones and self-tapping implants and pig rib bones. There was no statistically significant correlation between non-self-tapping dental implants in pig rib bones. Self-tapping and non-self-tapping implants did not show statistical significance in the primary stability in bones of different qualities. The analysis of bone density from CBCT images in the software of the apparatus expressed in HU units can be used to predict the degree of primary stability of self-tapping and non-self-tapping dental implants in bones of densities D1 and D2, and self-tapping dental implants in bones of the lower quality D4.

An Osteotomy Tool That Preserves Bone Viability: Evaluation in Preclinical and Clinical Settings

The main objectives of this work were to assess the efficiency, ease-of-use, and general performance of a novel osseoshaping tool based on first-user clinical experiences and to compare these observations with preclinical data generated in rodents using a miniaturized version of the instrument. All patients selected for the surgery presented challenging clinical conditions in terms of the quality and/or quantity of the available bone. The presented data were collected during the implant placement of 15 implants in 7 patients, and included implant recipient site (bone quality and quantity) and ridge evaluation, intra-operative handling of the novel instrument, and the evaluation of subsequent implant insertion. The instrument was easy to handle and was applied without any complications during the surgical procedure. Its use obviated the need for multiple drills and enabled adequate insertion torque in all cases. This biologically driven innovation in implant site preparation shows improvements in preserving vital anatomical and cellular structures as well as simplifying the surgical protocol with excellent ease-of-use and handling properties.

Morphological Characteristics of Maxillary Molars Interradicular Septum and Clinical Implications - What do We Know So Far?

The interradicular septum describes area in the root furcation that separate alveoli of multi-rooted teeth. The shape and dimension depend of the topography of the extraction socket, the geometry of residual root and anatomy of molars alveoli. The clinical implications of this anatomic structure may be used in oral surgery resection procedures, periodontology and implantology. There is an opinion from the surgical and prosthodontic side that center of interradicular septum may be adequate place for immediate implantation. The aim of this study was to investigate morphological characteristics and clinical implications of upper molars interradicular septum. The studies showed that interradicular septum is important for success of resection surgery procedures: hemi-section, bisection and root amputation. It’s reported that furcation involvement in periodontal disease is clinical sign for severe bone loss. By reviewing the available literature for immediate implantation, it’s reported the clinical implications for diagnostical plan (pre-intervention), presurgical (pre-instrumentation) and intraoperative evaluation of interradicular septum for immediate implantation. The cone beam computed tomography analyze study presented mean values of septum height and wide for hypothetical plan of immediate implant placement. The presurgical studies evaluate how to assure preservation of septum and safe implant position in center of septum. The research showed varies therapy modalities that can be used, and how to choose right therapy according the socket type and initial septum width classification. According to observation of studies results, other researches should be considered for CBCT anatomical structure analyze and measures of interradicular septum for immediate implantation planning.

Inter radicular bone dimensions in primary stability of immediate molar implants - A cone beam computed tomography retrospective analysis

Purpose

The purpose of the study was to analyze the dimensions of socket morphology, interradicular bone dimensions, root length and morphology, buccal cortical bone thickness and gap defect between the implant bone in mandibular molars with cone beam computed tomography (CBCT) for immediate molar implant (IMI) placement.

Materials and methods

Sample sizes of 300 mandibular 1st and 2nd molars were each selected from the CBCT scans by inclusion and exclusion criteria. CBCT measurements were performed for socket size morphology, mesiodistal width, and buccolingual cancellous bone width at the crest at the apex. Width of the buccal cortical plate at the crest and interradicular bone (IRB) at the apex, 3 mm cervical to the apex and 6 mm cervical to the apex. Vertical parameters from the crest to furcation (L1), length from furcation to the apex (L2) and mesiodistal root morphology were measured to analyze the root configuration.

Results

All the parameters were analyzed for descriptive statistics for the mean and standard deviation. The majority were of Type B and C socket morphology with peri-implant bone defects of 2–2.5 mm, and the interradicular bone septum (IRB) was moderate for both first molar (1 M) and second molar (2 M) sites, but 2 M was shown to have less IRB than 1 M. Adequate buccal cortical bone thickness of 1.1 mm to 1.4 mm and buccolingual cancellous bone width were measured for both the 1 M and 2 M sites.

Conclusion

The morphology of the molar extraction socket determines the adequate stability for IMI. In mandibular molar teeth, where interradicular bone is incompetent in providing good primary stability, in addition to interradicular bone, clinicians should look for support from the apical bone and interdental septal bone for attaining primary stability of IMI.

Dental Implants Inserted in Fresh Extraction Sockets versus Healed Sites: A Systematic Review and Meta-Analysis

The present review aimed to evaluate the difference of dental implant failure rates and marginal bone loss (MBL) between implants inserted in fresh extraction sockets or healed sites. Electronic search was undertaken in three databases, plus manual search of journals, including studies randomized or not. Meta-analyses were performed besides meta-regressions, in order to verify how the odds ratio (OR) and MBL were associated with follow-up time. The review included 163 publications. Altogether, there were 17,278 and 38,738 implants placed in fresh extraction sockets and healed sites, respectively. Pairwise meta-analyses showed that implants in sockets had a higher failure risk in comparison to healed sites: OR 1.349, all studies included; OR 2.070, only prospective non-RCTs; OR 2.487, only RCTs (all p < 0.001). The difference in implant failure between the groups was statistically significant in the maxilla (OR 1.616, p = 0.029), but not in the mandible (OR 2.192, p = 0.075). The MBL mean difference (MD) between the groups was −0.053 mm (p = 0.089). There was an estimated decrease of 0.003 in OR (p = 0.284) and an increase of 0.006 mm (p = 0.036) in the MBL MD between groups for every additional month of follow-up. In conclusion, implants placed in fresh extraction sockets present higher risk of failure than implants placed in healed sites.

Immediate Implant Placement in the Maxillary Aesthetic Zone: A Cone Beam Computed Tomography Study

This study aimed to investigate the factors that could be associated with the risk of labial cortical bone wall perforation with immediate implant placement (IIP) in the maxillary aesthetic zone, in a cone-beam computed tomography (CBCT) virtual study. CBCT exams from 126 qualified subjects (756 teeth) were included. Implants were virtually positioned in two different positions: in the long axis of the tooth (prosthetically-driven position) and in an ideal position in relation to adjacent anatomical structures (bone-driven position). Two different implant diameters were planned for each tooth position, namely, 3.75 and 4.3 mm for central incisors and canines, and 3.0 and 3.3 mm for lateral incisors. The incidence of perforation was nearly 80% and 5% for prosthetically- and bone-driven position, respectively. Factors associated with a higher risk of cortical bone wall perforation (bone-driven position), according to logistic regression analysis, were women, wider implants, Sagittal Root Position class IV, and decrease of the labial concavity angle. Perforation of the labial cortical bone wall can be greatly minimized when the implant is placed in a bone-driven position compared to a prosthetically-driven position. It is important to preoperatively evaluate the morphological features of the implant site for risk assessment and to individualize the treatment plan.

Buccal Bone Thickness in Anterior and Posterior Teeth-A Systematic Review

(1) Background: Immediate dental implant placement has been a subject of great interest over the last decade. Here, information regarding the anatomy and bone thickness of the jaw prior to dental implant placement is crucial to increase the surgery's success and the patient's safety. The clinical premises for this approach have been controversially discussed. One of those heavily discussed premises is a buccal bone thickness of at least 1 mm thickness. This meta-analysis aims to systematically review buccal bone thickness (BBT) in healthy patients. Thus, the feasibility of immediate dental implant placement in daily practice can be assessed. (2) Methods: A search in the electronic databases was performed to identify articles reporting on BBT that was measured by computed tomography in adults. (3) Results: We were able to find 45 studies, including 4324 patients with 25,452 analyzed teeth. The analysis showed a BBT at the alveolar crest of 0.76 ± 0.49 mm in the maxillary frontal and of 1.42 ± 0.74 mm in the maxillary posterior region. In the mandible, the average measured values were similar to those in the maxilla (front: 0.95 ± 0.58 mm; posterior: 1.20 ± 0.96 mm). In the maxillary frontal region 74.4% and in the mandibular frontal region 61.2% of the crestal buccal bones showed widths <1 mm. (4) Conclusions: In more than 60% of the cases, the BBT at the alveolar crest is <1 mm in maxillary and mandibular frontal regions. This anatomic data supports careful pre-surgical assessment, planning of a buccal graft, and critical selection of indication for immediate implant placement, especially in the maxillary and mandibular frontal and premolar region.

Immediately loaded implants simultaneously placed in fresh extraction and healed sites supporting four-implant-supported fixed mandibular prostheses using the all-on-4 concept: A 5-year prospective study

OBJECTIVES

To evaluate the peri-implant marginal bone level for immediately loaded implants placed simultaneously in both fresh extraction sites (FES) and healed sites (HS) supporting a 4-implant supported mandibular fixed prosthesis (4-ISFMP) using the all-on-4 concept.

MATERIAL AND METHODS

A 5-year prospective study was conducted in 24 patients (96 implants) treated with 4-ISFMP including 55 implants inserted in FES and 41 implants in HS. At implant placement (baseline) and at the 1^st -, 3^rd - and 5^th -year follow-up examinations, peri-implant marginal bone level was evaluated radiographically and compared between placement in FES and HS. Marginal bone loss was calculated as the difference in the marginal bone level evaluated at the follow-up periods. Additionally, implant and prosthesis survival rates as well as the presence of peri-implant mucositis (bleeding on probing+[BOP]) and peri-implantitis (BOP+ >2 mm MBL) were evaluated.

RESULTS

22/24 patients with 88/96 implants (dropout rate: 8.3%) were continually followed for 5 years (survival rate: 100%). Radiographically measured marginal bone level differed significantly between FES and HS at implant placement (1.46 ± 0.80 mm vs. 0.60 ± 0.70 mm; p < .001), at the 1-year (-0.04 ± 0.14 mm vs. -0.18 ± 0.20 mm; p = .002) and 3-year (-0.26 ± 0.49 mm vs. -0.58 ± 0.48 mm, p = .049), but not at the 5-year evaluation (-0.90 ± 0.66 mm vs. -1.00 ± 0.59 mm, p = .361). The marginal bone loss differed significantly (p < .001) between FES and HS between implant placement and the 1-year evaluation but not for the 1- to 3-year (p > .99) and the 3- to 5-year period (p = .082). At the 5-year follow-up evaluation, no implant/prosthesis failed (100% survival) and peri-implant mucositis and peri-implantitis were noted in 41.2% and 11.7% at patient level and in 17.6% and 4.5% at implant level respectively.

CONCLUSION

Implants placed in FES showed a prolonged peri-implant remodelling process but provided for similar peri-implant marginal bone levels as implants placed in HS at the 5-year evaluation for immediately loaded 4-ISFMP.

Consequences of Peri-Implant Bone Loss in the Occlusal Load Transfer to the Supporting Bone in terms of Magnitude of Stress, Strain, and Stress Distribution: A Finite Element Analysis

Methods

Three models of a single internal connection bone level-type implant inserted into a posterior mandible bone section were constructed using a 3D finite element software: one control model without marginal bone loss and two test models, both with a circumferential peri-implant bone defect, one with a 3 mm high defect and the other one 6 mm high. A 150 N static load was tested on the central fossa at 6° relative to the axial axis of the implant.

Results

The results showed differences in the magnitude of strain and stress transferred to the bone between models, being the higher strain found in the trabecular bone around the implant with greater marginal bone loss. Stress distribution differed between models, being concentrated at the cortical bone in the control model and at the trabecular bone in the test models.

Conclusion

Marginal bone loss around dental implants under occlusal loading influences the magnitude and distribution of the stress transferred and the deformation of peri-implant bone, being higher as the bone loss increases.

Risk assessment of labial bone perforation in the anterior mandibular region: a virtual immediate implant placement study

BACKGROUND

This study investigated the prevalence of labial bone perforation (LBP) related to the associated anatomic factors in anterior mandibular region using a virtual immediate implant placement procedure.

METHODS

Series qualified CBCT images of 149 participants (894 teeth) were selected to analyze the assigned anatomical parameters, including concavity depth, concavity angle, torque, and deep bone thickness. Four classes of crestal and radicular dentoalveolar bone phenotypes (CRDAPs) of mandibular anterior teeth were categorized according to the thickness of dentoalveolar bone at both crestal and radicular zones. Data were adjusted for categorical (gender and CRDAP) and continuous (age, cavity angle, cavity depth, and deep bone thickness) variables using a multivariable logistic regression analysis with generalized estimating equation method.

RESULTS

The overall probability of LBP after virtual implant placement was 21.6%. There is statistically significant higher prevalence of LBP at canine (28.5%) and CRDAP class II (29.2%) regions (p < 0.001). After adjusting confounding variables, CRDAP class II and class IV regions are more likely to have LBP when compared with CRDAP class I (control) regions (p < 0.01). The risk of LBP at canine site is 6.31 times more likely than at the central incisor (control) (p < 0.01).

CONCLUSIONS

Using a virtual immediate implant placement technique, the prevalence of LBP is significantly higher at the mandibular canine site and thin radicular dentoalveolar phenotype in the anterior mandibular region.

Immediate implant placement in fresh alveolar sockets with a minimal split-thickness envelope flap: A randomised controlled clinical trial

OBJECTIVES

Comparing PES/WES scores, modified success rate, survival, success, buccal bone thickness and patient-reported outcomes of immediate dental implants placed in fresh alveolar sockets using a flap or a minimal split-thickness envelope flap (MSTEF).

MATERIALS AND METHODS

Implants following random assignment into a flap or MSTEF group were placed immediately in anterior and premolar areas. Guided bone regeneration and autogenous connective tissue graft were used in all cases. A temporary prosthesis was provided followed by the final prosthesis at 16-18 weeks. Success and survival rates together with radiographic buccal bone thickness and patient satisfaction were evaluated at 12-month post-loading. The aesthetic outcome was evaluated through the Pink (PES) and White (WES) Aesthetic Score by 8 blind clinicians of different training background and incorporated in modified success criteria.

RESULTS

28 implants were placed on 28 patients. No statistically significant differences were noted in PES (10.54 control versus 10.80 test), WES scores (6.97 control versus 6.95 test) or success criteria including aesthetic parameters (modified success criteria) for the different specialty groups (Range 69%-92%). In addition, no statistically significant differences were noted in survival (100%), success (100%), buccal wall thickness between control (0.72 ± 0.22) and test group (0.92 ± 0.31) and patients' reported outcomes.

CONCLUSIONS

Immediate dental implant treatment with flap/ MSTEF provided similar mean PES/WES scores, modified success rate, survival, mean buccal bone levels and patients' satisfaction. However, aesthetic failures were common in both groups.

The Impact of Dental Implant Length on Failure Rates: A Systematic Review and Meta-Analysis

The present review aimed to evaluate the impact of implant length on failure rates between short (<10 mm) and long (≥10 mm) dental implants. An electronic search was undertaken in three databases, as well as a manual search of journals. Implant failure was the outcome evaluated. Meta-analysis was performed in addition to a meta-regression in order to verify how the risk ratio (RR) was associated with the follow-up time. The review included 353 publications. Altogether, there were 25,490 short and 159,435 long implants. Pairwise meta-analysis showed that short implants had a higher failure risk than long implants (RR 2.437, p < 0.001). There was a decrease in the probability of implant failure with longer implants when implants of different length groups were compared. A sensitivity analysis, which plotted together only studies with follow-up times of 7 years or less, resulted in an estimated increase of 0.6 in RR for every additional month of follow-up. In conclusion, short implants showed a 2.5 times higher risk of failure than long implants. Implant failure is multifactorial, and the implant length is only one of the many factors contributing to the loss of an implant. A good treatment plan and the patient’s general health should be taken into account when planning for an implant treatment.

Evaluation of hard tissue 3-dimensional stability around single implants placed with guided bone regeneration in the anterior maxilla: A 3-year retrospective study

STATEMENT OF PROBLEM

Guided bone regeneration (GBR) is widely used to reconstruct peri-implant bone defects in the esthetic zone. However, the dimensional stability of this bone-biomaterial composite is not fully understood.

PURPOSE

The primary aim was to evaluate the hard tissue 3-dimensional (3D) stability around single implants placed with simultaneous GBR by using deproteinized bovine bone mineral (DBBM) in the anterior maxilla and explore possible influencing factors.

MATERIAL AND METHODS

The records of patients who had received implants in the anterior maxilla from January 2015 to March 2016 were reviewed retrospectively. The change in volume and thickness of the facial hard tissue were analyzed. To explore possible influencing factors, the thickness and surface area of facial graft were measured, and the time point at which implants were placed and the healing protocol were recorded. Secondary outcome measures were peri-implant marginal bone loss, bleeding on probing (BOP), and pink esthetic score (PES). Statistical analysis was conducted by using the Student t test, Mann-Whitney U test, Kruskal-Wallis test, or generalized estimating equation analysis (α=.05).

RESULTS

Fifty-five participants were included in this study, and no implants had been lost after 3 years. BOP was present in 10 (18.2%) participants. The mean ±standard deviation PES of all implants for this study was 11.0 ±2.1. The mean ±standard deviation percentage of residual hard tissue volume was 36.9 ±23.5%, with a significant difference found between time points before 9 months (P<.05). Type 3 implant placement (OR=1.449, P=.031) was found to have a higher percentage of residual hard tissue volume. A greater reduction of the facial hard tissue thickness was observed in participants with thicker postoperative facial grafting (OR=1.463, P=.001). No statistically significant difference was found between the facial, palatal, mesial, and distal peri-implant sites in terms of marginal bone loss (P>.05).

CONCLUSIONS

Although single-tooth implant placement combined with GBR using DBBM in the anterior maxilla offered satisfactory esthetic and functional outcomes after a 3-year follow-up, significant hard tissue volume and thickness reduction in grafted sites was detected, especially during the initial 9-month postoperative period. This phenomenon may be correlated with the timing of implant placement and the thickness of the facial graft.

Comparison of extraction sites versus artificial defects with xenogenic bone substitute in minipigs

Objectives

The preclinical evaluation of bone substitutes is frequently performed in artificially created defects. However, such defects do not reflect the predominant clinical application of bone substitutes for socket preservation. Hence, the goal of this animal study was to compare the performance of a xenogenic bone substitute in extraction sites versus artificial defects.

Material and Methods

Four study sites each were created in the mandibles of four minipigs in the region of the third premolars and first molars, respectively. On one side, fresh extraction sockets were established while contralaterally trephine defects were created in healed alveolar bone. All sites were augmented using a particulate xenogenic bone substitute, covered by resorbable membranes and allowed to heal for 12 weeks. The amounts of new bone, non‐bone tissue and remaining bone substitute granules were quantified through histological and micro‐CT analysis. Comparative statistics were based on t‐tests for two samples and ANOVA with the level of significance set at α = 0.05.

Results

Histomorphometric data from only two animals could be quantitatively analyzed due to difficulty with identifying the surgical sites. The percentage of newly formed bone ranged between 53.2% ± 5.6% for artificial defects and 54.9% ± 12.4% for extraction sites. With the exception of ANOVA indicating a greater amount of non‐bone tissue in extraction sites as compared to artificial sites (p = 0.047), no statistically significant differences were observed. Micro‐CT scans showed patterns similar to the ones observed in histomorphometry. As extraction sites could be identified only in two micro‐CT reconstructions, quantitative assessment was not undertaken.

Conclusions

Despite the comparable performance of bone substitute material in artificial defects and extraction sites found here, the data gathered with this experiment was insufficient for showing equivalence of both approaches.

Factors Influencing Primary and Secondary Implant Stability—A Retrospective Cohort Study with 582 Implants in 272 Patients

The success rate of dental implants depends on primary and secondary stability. We investigate predictive factors for future risk stratification models. We retrospectively analyze 272 patients with a total of 582 implants. Implant stability is measured with resonance frequency analysis and evaluated based on the implant stability quotient (ISQ). A linear regression model with regression coefficients (reg. coeff.) and its 95% confidence interval (95% CI) is applied to assess predictive factors for implant stability. Implant diameter (reg. coeff.: 3.28; 95% CI: 1.89–4.66, p < 0.001), implant length (reg. coeff.: 0.67, 95% CI: 0.26–1.08, p < 0.001), and implant localization (maxillary vs. mandibular, reg. coeff.: −7.45, 95% CI: −8.70–(−6.20), p < 0.001) are significant prognostic factors for primary implant stability. An increase in ISQ between insertion and exposure is significantly correlated with healing time (reg. coeff.: 0.11, 95% CI: 0.04–0.19). Patients with maxillary implants have lower ISQ at insertion but show a higher increase in ISQ after insertion than patients with mandibular implants. We observe positive associations between primary implant stability and implant diameter, implant length, and localization (mandibular vs. maxillary). An increase in implant stability between insertion and exposure is significantly correlated with healing time and is higher for maxillary implants. These predictive factors should be further evaluated in prospective cohort studies to develop future preoperative risk-stratification models.

Long term survival of mature autotransplanted teeth: A retrospective single center analysis

OBJECTIVE

The replacement of an irremediably compromised tooth requires an implant rehabilitation or a traditional fixed partial denture. In well-selected cases, a further therapeutic possibility is represented by tooth autotransplantation. Although dental transplants are poorly understood and practiced, the international literature agrees that it is considered the first choice when applicable. The advantages of this technique are numerous: use of an autologous element, maintenance of tissue trophism, aesthetic and functional restoration, costs reduction. Although autotransplantation is often performed with immature teeth, even mature teeth with fully formed apex can be used as donors. The aim of the present work was to analyze consecutive cases of completely formed donor teeth autotransplantations performed from 2005 to 2011 in 21 patients for evaluating the survival and success rate.

MATERIALS AND METHODS

The medical records of patients who underwent transplantation in a specialized center in Rimini (Italy) from 2005 to 2011 were checked. Only transplants of mature donor molars were considered. Patients were called up to evaluate the survival rate and success rate.

RESULTS

The mean age at the time of the surgery was 33,6 ± 7,4; mean follow up was 11,9 years ±1,9. Success rate at the time of latest recall visit was 80 % and survival 95 % of the analyzed cases.

CONCLUSIONS

The survival and success rate are in complete agreement with the most recent literature and confirm that the technique of autotransplantation is reliable when indications and protocols are rigidly followed, also using mature teeth as donors.

Mandibular dental implant placement immediately after teeth removal in head and neck cancer patients

BACKGROUND

Little is known about immediate implant placement in head and neck cancer patients. We studied implant survival and functional outcomes of overdentures fabricated on implants placed immediately after removal of the lower dentition during ablative surgery or preceding primary radiotherapy (RT).

METHODS

Inclusion criteria were primary head and neck cancer, dentate lower jaw, and indication for removal of remaining teeth. Two implants to support a mandibular overdenture were placed immediately after extraction of the dentition during ablative surgery, or prior to starting primary radiotherapy. Standardized questionnaires and clinical assessments were conducted (median follow-up 18.5 months, IQR 13.3).

RESULTS

Fifty-eight implants were placed in 29 patients. Four implants were lost (implant survival rate 93.1%). In 9 patients, no functional overdenture could be made. All patients were satisfied with their dentures.

CONCLUSIONS

Combining dental implant placement with removal of remaining teeth preceding head neck oncology treatment results in a favorable treatment outcome.

The "One Piece" Autologous Tuberosity Graft: A Contemporary Concept in Ridge Preservation

Tooth extraction causes major changes to the ridge, rendering implant placement a more challenging procedure. Proper management of the socket is necessary to ensure sufficient bone and soft tissue for a successful implant-supported prosthesis. This article presents a practical approach for autologous hard and soft tissue grafting. A soft and hard tissue graft is harvested in one piece from the maxillary tuberosity and stabilized in the extraction socket.

The effectiveness of immediate implant placement for single tooth replacement compared to delayed implant placement: A systematic review and meta-analysis

AIM

To compare immediate implant placement (IIP) to delayed single implant placement (DIP, ≥3 months post-extraction) in terms of implant survival (primary outcome), surgical, clinical, aesthetic, radiographic and patient-reported outcomes (secondary outcomes).

MATERIALS AND METHODS

Two reviewers independently performed an electronic search in PubMed, Web of Science, EMBASE and Cochrane and a hand search to identify eligible studies up to May 2018. Only randomized controlled trials (RCTs) and non-randomized controlled studies (NRSs) comparing IIP to DIP with at least 1 year of follow-up were selected for a qualitative analysis and meta-analysis.

RESULTS

The search identified 3 RCTs and 5 NRSs out of 2,589 titles providing data on 473 single implants (IIP: 233, DIP: 240) that had been in function between 12 and 96 months. One RCT showed unclear risk of bias, whereas all other studies demonstrated high risk. Meta-analysis showed significantly lower implant survival for IIP (94.9%) as compared to DIP (98.9%) (RR 0.96, 95% CI [0.93; 0.99], p = 0.02). All were early implant failures. A subgroup meta-analysis demonstrated a trend towards lower implant survival for IIP when postoperative antibiotics had not been administered (RR: 0.93, 95% CI [0.86; 1.00], p = 0.07). This was not observed among studies including the administration of postoperative antibiotics (RR: 0.98, 95% CI [0.94; 1.02], p = 0.35). Meta-analyses showed similar probing depth (WMD 0.43 mm, 95% CI [-0.47; 1.33], p = 0.35) and aesthetic outcomes as assessed by the pink aesthetic score (standardized WMD -0.03, 95% CI [-0.46; 0.39], p = 0.88) for IIP and DIP. Data on marginal bone loss were conflicting and highly biased. Soft tissue recession was underreported and available data were highly biased. Patient-reported outcomes were underreported, yet both IIP and DIP seemed well tolerated.

CONCLUSION

Immediate implant placement demonstrated higher risk for early implant loss than DIP. There is a need for RCTs comparing IIP to DIP with CBCT analyses at different time points and data on midfacial recession with the preoperative status as baseline. In these studies, the need for hard and soft tissue grafting should also be evaluated.

Effect of guided bone regeneration on immediately placed implants: Meta-analyses with at least 12 months follow up after functional loading

INTRODUCTION

Immediate implant placement (IIP) into fresh extraction socket is a favorable treatment option. If successfully managed, it reduces the overall treatment time, and increases patient's satisfaction. Surgical and restorative factors affect IIP success rates. In this systematic review we evaluate the effect of guided bone regeneration (GBR) at the time of IIP on crestal bone level (CBL) changes after at least 12-months of functional loading.

METHODS

Reviewers conducted an independent search of the National Center for Biotechnology Information PubMed, Medline, and the Cochrane Collaboration Library from 1966 to January 2017 following the inclusion criteria. A hand search of bibliographies of reviews and clinical trials related to IIP was also performed. This study looked into CBL changes around IIP primarily and further extracted the data to conduct three meta-analysis of "IIP using GBR versus IIP without GBR", "IIP using bone graft alone versus IIP using bone graft with membrane" and "IIP using GBR versus conventional implant placement" which were further subdivided to provide more detailed information for each. Four reviewers independently assessed the study data and methodologic quality using data extraction and assessment forms.

RESULTS

The electronic search identified 714 potential studies and the hand search retrieved 55 studies. Crestal bone level (CBL) changes were determined in three meta-analyses. The results revealed a mean difference in CBL changes of 0.179 ± 0.174 mm  in favor of IIP without GBR when compared with implant with GBR. However, IIP with bone graft and membrane showed better results when compared with IIP with bone graft alone [CBL changes of 0.532 ± 0.572 mm]. CBL preservation was noted in IIP with GBR versus conventional implant placement [CBL changes of - 0.001 ± 0.049 mm].

CONCLUSIONS

Meta-analyses showed minimal difference in CBL around IIP with bone graft versus without bone graft and with IIP with GBR compared with conventional implant placement. However, IIP with bone graft and membrane reported better CBL preservation compared with IIP with bone graft alone. Nonetheless, these results should be interpreted with caution because of moderate heterogeneity between studies.

One-Piece Implants with Smooth Concave Neck to Enhance Soft Tissue Development and Preserve Marginal Bone Levels: A Retrospective Study with 1- to 6-Year Follow-Up

Novel one-piece implants with concave smooth neck have been introduced to promote the formation of a thick mucosal layer and preserve marginal bone. A retrospective study on 70 patients with 1- to 6-year follow-up was carried out. Cumulative survival rates were assessed. Variations of marginal bone level were measured on periapical radiographs as distance of the implant-abutment junction from the bone crest. Influence of different variables on treatment outcome was evaluated. Cumulative success rate after 6 years was 99.4 % at implant level and 98.6 % at patient level. Marginal bone level changed in a significant way over time. After 4 months, an increase of radiographic bone level of 0.173 ± 1.088 mm at implant level and 0.18 ± 1.019 mm at patient level was recorded. Mean marginal bone loss after 5 years was 0.573 ± 0.966 mm at implant level and 0.783 ± 1.213 mm at patient level. Age, sex, smoking habits, implant sites, implant lengths and diameters, prosthetic retentions, and timing of loading did not influence marginal bone remodeling in a statistically significant way. At 4-year follow-up partial restorations lost a mean of 0.96 mm of more marginal bone compared with single restorations. This difference was statistically significant.

Controversies in Implant Surgery

Dental implants are a mainstream treatment protocol to replace missing teeth. Patient and clinician demands have led to shorter length and narrower diameter implants, immediately placed implants into infected sites, and the use of implants in children. This article reviews some of the controversial topics in implant dentistry, and presents the evidence that supports and challenges these newer techniques. Because long-term studies are often not available, especially for implants in infected sites, mini implants, and implants in the growing patient, the field continues to evolve.

Immediate Early and Delayed Implants: A 2-Year Prospective Cohort Study of 131 Transmucosal Flapless Implants Placed in Sites With Different Pre-extractive Endodontic Infections

INTRODUCTION

To evaluate clinical outcome of early, immediate, and delayed transmucosal implants placed in patients affected by acute/chronic endodontic lesions.

MATERIALS AND METHODS

Eighty-five consecutive patients received 131 titanium implants with zirconium-oxide blasted surface. Pre-extractive diagnosis represented the main criteria for implant placement timing, following "best treatment" criteria. Implants were placed with flapless transmucosal technique. Hopeless teeth with chronic periapical lesions received atraumatic extraction, and an implant was immediately placed (Immediate Group, n = 29). Teeth with acute periapical lesion/abscess were extracted and implants placed after 8 to 12 weeks (Early Group, n = 29). Implants placed 10- to 12-month after extraction constituted the control group (delayed group, n = 73). Implants were loaded 3 months after insertion with provisional resin crowns and after approximately 15 days with definitive ceramic crowns. Marginal bone loss (MBL) was measured in a single-blind manner on periapical radiographs at 1, 3, 6, 12, and 24 months.

RESULTS

Multilevel analysis described exploring factors associated with MBL. Survival rate was 100%. MBL after 24 months was 0.78 ± 0.70 (95% confidence interval [CI]: 0.20 to -1.37) at immediate, 0.48 ± 0.70 at early (95% CI: -0.006 to -0.961), and 1.02 ± 1.01 (95% CI: 0.61 to -1.43) at delayed groups. Implant groups (immediate/early/delayed) and location (maxillary/mandibular) showed statistically significant results. Early group showed the lowest MBL values. The immediate group demonstrated less MBL than the delayed group.

CONCLUSION

Early implant placement technique preserves periimplant marginal bone level more than immediate and delayed techniques.

An up to 17-year follow-up retrospective analysis of a minimally invasive, flapless approach: 18 945 implants in 7783 patients

BACKGROUND

This study investigates gender, age, jaw, implant position, loading protocol (immediate vs delayed), smoking, and type of surgery (punch vs flap) as influential factors of implant survival in a large patient collective.

PURPOSE

To evaluate the survival rates of implants in patients using a mucoperiosteal punch for flapless implantation in the majority of cases in order to evaluate its medical efficacy and safety.

MATERIALS AND METHODS

Between 1994 and 2015 all patients with complete data treated at the Wienerberg Dental Clinic, Vienna, Austria, were included and statistically analyzed in Cox proportional hazard (PH) models. As patients with multiple implants were included, a clustering term was added to the Cox PH model to respect pooled failures in patients.

RESULTS

Of the initial 24 282 ANKYLOS/Dentsply implants placed in 8137 patients a total of 7783 patients with 18 945 implants were finally included. The mean follow-up was 2.8 ± 3.2 up to 17.9 years. Cumulative survival rates (CSRs) after 1, 3, 5, and 10 years were 98.5%, 97.7%, 96.7%, and 93.0%, respectively. Of these, 17 517 (92.5%) implants were placed minimally invasive via a flapless approach by use of the ATP-Punch with comparable survival rates as observed for flap surgery. The Cox PH models proved smoking (hazard ratio [HR] = 2.2) and implant position as significant factors of implant survival. In the maxilla, canines and third molars were identified as low risk sites in comparison to the most frequently implanted first premolar site. In the mandible, the central incisor and second premolar were identified as high-risk sites, the canine as low risk site in comparison to the most frequently placed first molar site.

CONCLUSION

The analyzed data concludes the safety and medical efficacy of the ATP-Punch. The CSRs using this flapless technique are comparable to the classic surgical flap approach.

Survival Rate of Delayed Implants Placed in Healed Extraction Sockets is Significantly Higher Than That of Immediate Implants Placed in Fresh Extraction Sockets

ARTICLE TITLE AND BIBLIOGRAPHIC INFORMATION

Immediate implant placement into fresh extraction sockets versus delayed implants into healed sockets: a systematic review and meta-analysis. Mello CC, Lemos CAA, Verri FR, Dos Santos DM, Goiato MC, Pellizzer EP. Int J Oral Maxillofac Surg 2017; 46(9):1162-77.

SOURCE OF FUNDING

None TYPE OF STUDY/DESIGN: Systematic review with meta-analysis of data.

Immediate implant placement into posterior sockets with or without buccal bone dehiscence defects: A retrospective cohort study

OBJECTIVES

To evaluate bone reconstruction and soft tissue reactions at immediate implants placed into intact sockets and those with buccal bone dehiscence defects.

METHODS

Fifty-nine internal connection implants from four different manufacturers were immediately placed in intact sockets(non-dehiscence group, n=40), and in alveoli with buccal bone dehiscence defects: 1) Group 1(n= N10), the defect depth measured 3-5 mm from the gingival margin. 2) Group 2(n=9), the depth ranged from 5mm to 7mm. The surrounding bony voids were grafted with deproteinized bovine bone mineral (DBBM) particles. Cone beam computed tomography(CBCT) was performed immediately after surgery (T1), and at 6 months later(T2). Radiographs were taken at prosthesis placement and one year postloading(T3). Soft tissue parameters were measured at baseline (T0), prosthesis placement and T3.

RESULTS

No implants were lost during the observation period. For the dehiscence groups, the buccal bone plates were radiographically reconstructed to comparable horizontal and vertical bone volumes compared with the non-dehiscence group. Marginal bone loss occurred between the time of final restoration and 1-year postloading was not statistically different(P=0.732) between groups. Soft tissue parameters did not reveal inferior results for the dehiscence groups.

CONCLUSIONS

Within the limitations of this study, flapless implant placement into compromised sockets in combination with DBBM grafting may be a viable technique to reconstitute the defected buccal bone plates due to space maintenance and primary socket closure provided by healing abutments and bone grafts.

CLINICAL SIGNIFICANCE

Immediate implants and DBBM grafting without using membranes may be indicated for sockets with buccal bone defects.

Immediate Loading of Tapered Implants Placed in Postextraction Sockets and Healed Sites

OBJECTIVE

The aim of the present study was to compare the survival, stability, and complications of immediately loaded implants placed in postextraction sockets and healed sites.

METHODS

Over a 2-year period, all patients presenting with partial or complete edentulism of the maxilla and/or mandible (healed site group, at least 4 months of healing after tooth extraction) or in need of replacement of nonrecoverable failing teeth (postextraction group) were considered for inclusion in this study. Tapered implants featuring a nanostructured calcium-incorporated surface were placed and loaded immediately. The prosthetic restorations comprised single crowns, fixed partial dentures, and fixed full arches. Primary outcomes were implant survival, stability, and complications. Implant stability was assessed at placement and at each follow-up evaluation (1 week, 3 months, and 1 year after placement): implants with an insertion torque (IT) <45 N·cm and/or with an implant stability quotient (ISQ) <70 were considered failed for immediate loading. A statistical analysis was performed.

RESULTS

Thirty implants were placed in postextraction sockets of 17 patients, and 32 implants were placed in healed sites of 22 patients. There were no statistically significant differences in ISQ values between the 2 groups, at each assessment. In total, 60 implants (96.8%) had an IT ≥45 and an ISQ ≥70 at placement and at each follow-up control: all these implants were successfully loaded. Only 2 implants (1 in a postextraction socket and 1 in a healed site, 3.2%) could not achieve an IT ≥45 N·cm and/or an ISQ ≥70 at placement or over time: accordingly, these were considered failed for stability, as they could not be subjected to immediate loading. One of these 2 implants, in a healed site of a posterior maxilla, had to be removed, yielding an overall 1-year implant survival rate of 98.4%. No complications were reported. No significant differences were reported between the 2 groups with respect to implant failures and complications.

CONCLUSION

Immediately loaded implants placed in postextraction sockets and healed sites had similar high survival and stability, with no reported complications. Further long-term studies on larger samples of patients are needed to confirm these results.

Implant Stability in the Posterior Maxilla: A Controlled Clinical Trial

Aim

To evaluate the primary and secondary stability of implants in the posterior maxilla.

Methods

Patients were allocated into three groups: (A) native bone, (B) partially regenerated bone, and (C) nearly totally regenerated bone. Insertion torque (IT) and implant stability quotient (ISQ) were measured at placement, to evaluate whether satisfactory high primary stability (IT ≥ 45 N/cm; ISQ ≥ 60) was achieved; ISQ was measured 15, 30, 45, and 60 days after placement, to investigate the evolution to secondary stability.

Results

133 implants (Anyridge®, Megagen) were installed in 59 patients: 55 fixtures were placed in Group A, 57 in Group B, and 21 in Group C. Fifty-two implants had satisfactory high primary stability (IT ≥ 45 N/cm; ISQ ≥ 60). A positive correlation was found between all variables (IT, ISQ at t = 0, t = 60), and statistically higher IT and ISQ values were found for implants with satisfactory high primary stability. Significant differences were found for IT and ISQ between the groups (A, B, and C); however, no drops were reported in the median ISQ values during the healing period.

Conclusions

The evaluation of the primary and secondary implant stability may contribute to higher implant survival/success rates in critical areas, such as the regenerated posterior maxilla. The present study is registered in the ISRCTN registry with ID ISRCTN33469250.

Immediate Loading of Single Implants in the Anterior Maxilla: A 1-Year Prospective Clinical Study on 34 Patients

Purpose

To present the outcomes of immediately loaded single implants placed in the anterior maxilla.

Methods

Over a 2-year period, all patients referred to a private clinic were considered for enrolment in this study. Inclusion criteria were single-tooth placement in postextraction sockets or healed sites of the anterior maxilla. All implants were immediately loaded and followed for a period of 1 year after the placement of definitive crowns. The outcome measures were implant stability, survival, and success.

Results

34 patients were selected and 43 tapered implants with a knife-edge thread design and a nanostructured, calcium-incorporated surface (Anyridge®, Megagen, Gyeongsang, Korea) were installed. Two implants were not sufficiently stable at placement (ISQ < 60) and were considered failed for immediate loading; 41 implants had an ISQ ≥ 60 at placement and were immediately loaded. One year after the placement of definitive crowns, no implant failures were reported, for a survival rate of 100%. No biological complications were found, but 2 implants had their prosthetic abutments loosened: the implant success rate was 95.2%.

Conclusions

In the present study on the immediate loading of single implants in the anterior maxilla, positive outcomes were reported, with high survival (100%) and success (95.2%) rates (the present study has been registered in the ISRCTN registry, a publicly available trial register recognized by WHO and ICMJE, with number ISRCTN12935478).

Clinical and radiographic outcomes of immediate and delayed placement of dental implants in molar and premolar regions

PURPOSE

The purpose of this retrospective study was to determine clinical and radiographic outcomes of immediate and delayed placement of dental implants in molar and premolar regions.

MATERIALS AND METHODS

Clinical and radiographic records of 116 patients who received implants in molar and premolar regions were included in this study. After implantation, patients were recalled for assessments at 1 month, 3 months, 6 months, 1 year, and every year thereafter. In addition, anatomic location, type of prosthesis, gender, stage, diameter, and length of implants were analyzed.

RESULTS

Of these 116 patients, 55 were males, and 61 were females. Their mean age was 50.9 years. They received 85 immediate implants and 147 delayed implants in molar and premolar regions. Gender, type of prosthesis, stage, implant diameter, and implant length were not significantly different between the immediate placement group and the delayed placement group, although anatomic locations were significantly different between the 2 groups. Their mean follow up time after dental implantation was 3 years (range, 6 months to 9 years). Kaplan-Meier survival estimates showed 97.8% probability of survival up to 9 years in the delayed placement group and 100% probability of survival up to 8 years in the immediate placement group. There was no significant difference in implant survival according to the time of implantation. No significant difference in cervical bone loss (CBL) at the mesial or distal side was found between the 2 groups. CBL according to anatomic location, the type of prosthesis, or gender was not significantly different either between the 2 groups. However, CBL at distal side of 1-stage approach was significantly (P < .05) smaller in the delayed placement group than that in the immediate placement group.

CONCLUSION

This study showed that immediate dental implantation in molar and premolar regions had good clinical and radiographic outcomes.

Morse Taper Implants Immediately Loaded in Fresh Extraction Sockets: A Prospective Cohort Study

PURPOSE

To evaluate survival rate and bone response around immediate loaded Morse taper implants installed in fresh sockets on the anterior area of the maxilla.

MATERIAL AND METHODS

The sample comprised 16 patients in whom 16 single implants were installed. All the teeth were extracted in a flapless surgery. Radiographic and tomographic evaluations were performed immediately after surgery (T1) and after 12 months (T2). The variables studied were height of the buccal wall (HBW), buccal wall width (BW) at 3 levels, and proximal bone height at 2 different areas: the alveolar crest level (CLH) and at the point where bone tissue meets the implant surface (BIS).

RESULTS

Statistically significant differences were observed. The buccal plate showed bone loss in height (HBW = -0.50 ± 0.42 mm) and in width (BW-1 = -0.71 ± 0.48 mm; BW-2 = -0.48 ± 0.34 mm; BW-3 = -0.48 ± 0.34 mm). In the proximal areas, there was also bone loss in height (CLH-M = -0.85 ± 0.89 mm; BIS-M = -0.91 ± 0.70 mm; CLH-D = -0.64 ± 0.57 mm; and BIS-D = -0.68 ± 0.62 mm).

CONCLUSION

There was 100% survival rate after a 12-month period, but bone loss was observed in all evaluated areas.

Is the intake of selective serotonin reuptake inhibitors associated with an increased risk of dental implant failure?

The aim of this retrospective study was to investigate the association between the intake of selective serotonin reuptake inhibitors (SSRIs) and the risk of dental implant failure. Patients were included if they were taking SSRIs only and no other medication, did not present any other systemic condition or compromising habits (bruxism, smoking, snuff), and complied with the use of prophylactic antibiotics for implant surgery. The multivariate generalized estimating equation (GEE) method and multilevel mixed-effects parametric survival analysis were used to test the association between SSRI exposure (predictor variable) and the risk of implant failure (outcome variable), adjusting for several potential confounders (other variables). The total number of implants with information available and meeting the necessary eligibility criteria was 931 (35 failures). These were placed in 300 patients. The implant failure rate was 12.5% for SSRI users and 3.3% for non-users (P=0.007). Kaplan-Meier analysis showed a statistically significant difference in the cumulative survival rate (P<0.001). The multivariate GEE model did not show a statistically significant association between SSRI intake and implant failure (P=0.530), nor did the multilevel model (P=0.125). It is suggested that the intake of SSRIs may not be associated with an increased risk of dental implant failure.

Early Bone Formation around Immediately Loaded Transitional Implants Inserted in the Human Posterior Maxilla: The Effects of Fixture Design and Surface

Aim. To evaluate the effects of fixture design and surface on the early bone formation around immediately loaded implants inserted in the human posterior maxilla. Materials and Methods. Ten totally edentulous subjects received two transitional implants: one tapered implant with knife-edge threads/nanostructured calcium-incorporated surface (test: Anyridge®, Megagen, Gyeongbuk, South Korea) and one cylindrical implant with self-tapping threads/sandblasted surface (control: EZPlus®, Megagen). The implants were placed according to a split-mouth design and immediately loaded to support an interim complete denture; after 8 weeks, they were removed for histologic/histomorphometric analysis. The bone-to-implant contact (BIC%) and the bone density (BD%) were calculated. The Wilcoxon test was used to evaluate the differences. Results. With test implants, a mean BIC% and BD% of 35.9 (±9.1) and 31.8 (±7.5) were found. With control implants, a mean BIC% and BD% of 29.9 (±7.6) and 32.5 (±3.9) were found. The mean BIC% was higher with test implants, but this difference was not significant (p = 0.16). Similar BD% were found in the two groups (p = 0.9). Conclusions. In the posterior maxilla, under immediate loading conditions, implants with a knife-edge thread design/nanostructured calcium-incorporated surface seem to increase the peri-implant endosseous healing properties, when compared to implants with self-tapping thread design/sandblasted surface.