Immediate Implant Placement: Positives and Negatives

Histological evaluation of osseointegration between conventional and novel bone-level tapered implants in healed bone-A preclinical study

AIMS

To histologically compare osseointegration and crestal bone healing between newly introduced tapered, self-cutting bone-level test implants and tapered bone-level control implants in sites with fully healed sites.

METHODS

Sixty-six implants (33 test, 33 control) were placed 1 mm subcrestally in a minipig model and underwent qualitative histologic and quantitative histometric analyses after 3, 6 and 12 weeks of submerged healing. The primary and secondary outcomes were the bone-to-implant contact (BIC) and first bone-to-implant contact (fBIC). Outcomes between the test and control implants were statistically compared.

RESULTS

The BIC values of the test implants were comparable and non-inferior over the time points studied, except for the 12 weeks time point which showed statistically significantly higher BIC values of the test (88.07 ± 5.35%) compared to the control implants (80.88 ± 7.51%) (p = .010). Similarly comparable and non-inferior were the fBIC values, except for the 6-week outcome, which showed statistically higher values for the test (-546.5 ± 450.80 μm) compared to the control implants (-75.7 ± 100.59 μm). fBIC results for the test implants were qualitatively more stable and consistent between test time points.

CONCLUSION

Novel self-cutting bone-level test implants demonstrated superior osseointegration and similar bone levels compared to conventional bone-level implants after a healing period of 12 weeks in healed ridges.

Placement of immediate dental implants in extraction sockets exhibiting the apical pathosis. A meta-analysis

Objectives

It is commonly accepted that immediate implantation is the best option for patients since it shortens the time patients must wait for ultimate restoration and provides a predictable functional and aesthetic result. However, this approach is still controversial in patients with apical pathosis. The goal of this systematic review and meta-analysis was to determine the efficacy of immediate implant insertion in patients with apical pathosis.

Material and methods

Between 2000 and 2023, PRISMA-compliant keywords were used to search PubMed, MEDLINE, CENTRAL, and the Cochrane Library. All English-language clinical studies that met PICOS criteria were included in a manual search. The included studies' demographic profile and event data for immediate dental implantation success in patients with or without apical pathosis were meta-analyzed using RevMan. The implant survival rate was assessed using risk ratio of plaque index and bleeding index. Begg's test using MedCalc and RevMan risk of bias assessment assessed publication bias.

Results

A meta-analysis of 10 trials with 849 dental implantation patients found a substantial difference in initial implant placement success rates in infected sites. The pooled risk ratio for plaque index is 0.59 (95% CI: 0.36-0.96) with heterogeneity of Tau2 = 0.62, chi2 = 109.69, df = 11, I2 = 90%, z = 2.12, and p < 0.05. While, the pooled risk ratio for bleeding index is 0.77 (95% CI: 0.60 to 0.98) with Tau2 = 0.16, chi2 = 103.67, df = 11, I2 = 89%, z = 2.12, and p < 0.05. The pooled odds ratio of implant survival rate is 2.08 (95% CI: 1.56 to 1.79) with Tau2 0.16; chi2 52.43; df 9; I2 83%; z 4.93 and p < 0.05. As evidenced by the funnel plot and statistically insignificant Begg's test p values of 0.45.

Conclusion

The placement of immediate implants in locations affected by apical pathosis is a clinically beneficial surgery, resulting in favorable aesthetic and functional outcomes for patients.

Comprehensive analysis of the maxillary esthetic zone for immediate implant placement using cone beam computed tomography: A study of 352 maxillary images

STATEMENT OF PROBLEM

Previous studies have examined the maxillary esthetic zone for immediate implant placement, but these studies had small sample sizes and did not investigate multiple parameters.

PURPOSE

The purpose of this cross-sectional study was to use cone beam computed tomography (CBCT) to evaluate the sagittal root position (SRP), alveolar bone concavity, labial bone perforation (LBP), and tooth-ridge angle in the maxillary anterior teeth region.

MATERIAL AND METHODS

A total of 352 CBCT images of patients (180 men and 172 women) who visited the dental hospital between 2018 and 2023 were analyzed. The sample included 2112 anterior maxillary teeth. SRP, alveolar bone concavity, tooth ridge angle, and LBP were assessed using virtual implant simulation. The data were analyzed by using chi-squared and kappa tests to analyze distributions and agreement, respectively, dependent and independent t-tests to assess sex and tooth-specific differences, and the Spearman correlation test to explore potential correlations (α<.05).

RESULTS

The CBCT images revealed that the majority of SRP were in Class I (85.4%), with smaller percentages in Class II (12.5%) and Class IV (2.3%); Class III was the least common (1%). The canine exhibited the most significant alveolar bone concavity angle average (149.14 ±6.35 degrees), followed by the lateral incisor (142.32 ±8.7 degrees). The canines had the highest occurrence of LBP (63.1%) (P<.01). Women had a higher frequency of labial bone perforation and deeper alveolar bone concavities than men (P<.01).

CONCLUSIONS

The findings of this study indicate that careful assessment and planning are necessary for immediate implant placement in the maxillary anterior region. The significant occurrence of LBP highlights the importance of thorough planning and evaluation to avoid surgical mishaps and complications which may necessitate bone grafting and result in added costs and time. Special attention should be given to women and the canine area.

Effect of implant shape and length on the accuracy of robot-assisted immediate implant surgery: An in vitro study

OBJECTIVES

To compare the accuracy of immediate implant placement of cylindrical implants (CI) and tapered implants (TI) of different lengths using a robotic dental implant system.

MATERIALS AND METHODS

CI and TI of three lengths (8, 10, and 12 mm) each were digitally planned and placed in a three-dimensional printed extraction socket model under robotic guidance. There were six groups with three samples in each group, resulting in a total of 18 samples. Implant angular deviation, platform point deviation (total, lateral, depth), and implant apical point deviation (total, lateral, depth) were recorded and compared between the different groups.

RESULTS

The angular deviations for CI 8 mm, CI 10 mm, CI 12 mm, TI 8 mm, TI 10 mm, and TI 12 mm were 1.32° ± 0.19°, 1.03° ± 0.56°, 1.31° ± 0.38°, 1.27° ± 0.64°, 1.10° ± 0.43° and 1.05° ± 0.45°, respectively. The total deviations of platform and apical points for CI 8 mm, CI 10 mm, CI 12 mm, TI 8 mm, TI 10 mm, and TI 12 mm were 0.79 ± 0.18 mm, 0.77 ± 0.33 mm; 0.64 ± 0.21 mm, 0.55 ± 0.17 mm; 0.64 ± 0.37 mm, 0.65 ± 0.34 mm; 0.68 ± 0.26 mm, 0.71 ± 0.20 mm; 0.70 ± 0.12 mm, 0.66 ± 0.23 mm; and 0.71 ± 0.15 mm, 0.77 ± 0.29 mm, respectively, and had no significant differences.

CONCLUSIONS

Within the limitation of this study, acceptable accuracy can be achieved for both TI and CI using robotic systems. Our study demonstrated that the implant shape and length did not affect the accuracy of immediate implant placement under robotic guidance in vitro. However, further trials are required to confirm their efficacy in clinical practice.

A graftless maxillary sinus lifting approach with simultaneous dental implant placement: a prospective clinical study

PURPOSE

This study aimed to introduce a graftless sinus lifting approach with simultaneous dental implant placement in the alveolus of the posterior maxilla and compare this approach's outcomes in freshly extracted sockets versus healed sockets.

MATERIALS AND METHODS

A prospective study was conducted on 60 patients aged between 27 and 59 years old, requiring dental implants in the posterior maxilla, and diagnosed with reduced vertical bone height (30 with freshly extracted sockets (group A) and the remaining 30 with healed sockets (group B). Before the sinus lifting approach, a cone beam computed tomography (CBCT) was taken, followed by another CBCT at least one-year post-sinus lifting (range: 12-36 months). Biological and mechanical complications were assessed, and the primary implant stability was measured using the Implant Stability Quotient (ISQ). Parametric data were analyzed using an independent t-test for intergroup comparisons, with significance set at P < 0.05.

RESULTS

No significant differences were found among groups concerning gender, placement side, and follow-up. All dental implants demonstrated high survival rates with no observed biological or mechanical complications. Moreover, the primary implant stability was satisfactory, and there was no statistically significant difference (P = 0.38). In terms of new intrasinus bone formation, both groups exhibited satisfactory and successful outcomes, with increased new bone formation in group A. However, there was no statistically significant difference (P = 0.26). Regarding the vertical sinus floor elevation without new bone formation, group B showed (0.11 ± 0.64) mm of intrasinus implant height without bone formation, while group A showed an increment of bone formation above the intrasinus implant (0.22 ± 0.33) mm, with no statistically significant difference between both groups (P = 0.30).

CONCLUSION

Our approach proves to be predictable, low-cost, and efficient option for sinus lift procedures, demonstrating high survival rates with acceptable primary implant stability. Moreover, it yields satisfactory outcomes in terms of new intrasinus bone formation, both in freshly extracted and healed sockets. Consequently, our approach holds promise as a reliable procedure for sinus lifting with simultaneous dental implant placement.

A clinical protocol for immediate dental implant placement in post-extraction-infected sites decontaminated with Er,Cr:YSGG laser

BACKGROUND

Placement of dental implants into fresh extraction sockets offers some advantages, such as reduced treatment times and enhanced patient comfort. The Er,Cr:YSGG (Erbium, Chromium-doped: Yttrium, Scandium, Gallium, and Garnet) laser can significantly reduce bacterial concentration after the extraction of a compromised tooth. The aim of this article is to provide a clinical protocol for the management of implants placed in infected extraction sites decontaminated with Er,Cr:YSGG laser.

METHODS

A compromised tooth, which was an abutment for a fixed bridge, with clinical and radiological signs of infection was extracted. The infected site was treated and decontaminated with an Er,Cr:YSGG laser device (Biolase iPlus®) and two implants (Straumann®) were placed in the same surgery, in order to rehabilitate the edentulous area. The intervention was completed by tissue regeneration with biomaterials.

RESULTS

Prosthetic rehabilitation after the surgical phase allowed us to provide correct function and satisfactory esthetics. In the follow-up visit, clinicians found good tissue healing and did not observe any complications, such as implant loss or peri-implantitis. The technique used in our study is repeatable and predictable, but patient selection is very important for this type of protocol as the presence of contraindications can lead to failure. The photoacoustic effect exerted by this type of laser has been proven to be effective against many pathogens. Several authors have previously demonstrated the effectiveness of this technique.

CONCLUSIONS

Immediate implantation in infected sites decontaminated with Er,Cr:YSGG laser does not seem to contribute to an increased risk of failure; however, it is necessary to follow a certain set of protocols and procedures to prevent peri-implantitis and other complications.

Evaluation of micromotion in multirooted root analogue implants embedded in synthetic bone blocks: an in vitro study

BACKGROUND

While conventional threaded implants (TI) have proven to be effective for replacing missing teeth, they have certain limitations in terms of diameter, length, and emergence profile when compared to customised root analogue implants (RAI). To further investigate the potential benefits of RAIs, the aim of this study was to experimentally evaluate the micromotion of RAIs compared to TIs.

METHODS

A 3D model of tooth 47 (mandibular right second molar) was segmented from an existing cone beam computed tomography (CBCT), and a RAI was designed based on this model. Four RAI subgroups were fabricated as follows: 3D-printed titanium (PT), 3D-printed zirconia (PZ), milled titanium (MT), milled zirconia (MZ), each with a sample size of n = 5. Additionally, two TI subgroups (B11 and C11) were used as control, each with a sample size of n = 5. All samples were embedded in polyurethane foam artificial bone blocks and subjected to load application using a self-developed biomechanical Hexapod Measurement System. Micromotion was quantified by analysing the load/displacement curves.

RESULTS

There were no statistically significant differences in displacement in Z-axis (the loading direction) between the RAI group and the TI group. However, within the RAI subgroups, PZ exhibited significantly higher displacement values compared to the other subgroups (p < 0.05). In terms of the overall total displacement, the RAI group showed a statistically significant higher displacement than the TI group, with mean displacement values of 96.5 µm and 55.8 µm for the RAI and TI groups, respectively.

CONCLUSIONS

The RAI demonstrated promising biomechanical behaviour, with micromotion values falling within the physiological limits. However, their performance is less predictable due to varying anatomical designs.

Immediate placement and loading of implants with laser-microgrooved collar in combination with an anorganic porcine bone mineral matrix in the esthetic zone. Twelve-month results of a prospective multicenter cohort study

BACKGROUND

Many techniques have been proposed to address post-extraction ridge resorption, which often represents a concern, especially in the esthetic region.

PURPOSE

The purpose of the present, prospective, multicenter, single cohort study was to investigate, up to 1 year of function, the effectiveness of a protocol for alveolar ridge preservation involving implants with laser-microgrooved surface immediately placed in fresh extraction sockets.

MATERIALS AND METHODS

Twenty eight patients candidate to tooth extraction in the esthetic zone (site 15-25 and 35-45) were treated by immediate placement of a single laser-microgrooved implants with the adjunct of a highly porous anorganic porcine bone mineral matrix and a collagen wound dressing. Peri-implant marginal bone level (MBL) was evaluated at time of loading, 3 and 12 months after loading. Gingival index, plaque index, probing depth, and bleeding on probing were measured at 3, 6, and 12 months after loading. Dimensional changes at implant sites were digitally evaluated using the best-fit superimposition of pre-and post-socket preservation models. Implant aesthetic score (IAS) as well as patients' post-operative quality of life were also evaluated at 12 months. Comparisons between data relative to thick and thin gingival phenotypes were made using Student's t-test or Mann-Whitney test, as appropriate. The significance level was set at p = 0.05.

RESULTS

No patient dropped out, and 28 implants were evaluated at 12 months post-loading. The overall MBL was found to be 0.92 ± 1.11 mm. Volumetric analysis of superimposed models showed an alveolar bone tissue displacement at the buccal aspect of -0.57 ± 0.52 mm in thin phenotypes and -0.46 ± 0.31 mm in thick phenotypes (p = 0.58, unpaired Student's t-test). No signs of soft tissue recession or esthetically unpleasant buccal gingiva were reported.

CONCLUSIONS

The clinical protocol herein employed showed benefits in maintaining marginal bone levels and soft tissue contour around post-extraction implants in the esthetic zone.

Tent-pole technique for alveolar ridge width preservation with a compromised buccal plate: a prospective cohort study

Objectives

The aim of this study was to assess the effectiveness of the tent-pole technique for alveolar ridge preservation of compromised alveolar socket following the surgical extraction of incurable single root premolars.

Materials and methods

This study was conducted on 12 patients who presented to the department of oral and maxillofacial surgery and had alveolar ridge preservation using tent-pole technique between August 2021 and February 2022. The alveolar ridge width was analyzed using cone beam computed tomography scans taken preoperative and 6 months postoperative. Statistical analysis was performed to assess the alveolar ridge width at different levels. The alveolar ridge width differences between periods were assessed with paired t-test. The comparison of alveolar ridge width loss according to jaw, sex, and different levels were done with unpaired t-test. The level of significance considered was 5% (α=0.05).

Results

The mean alveolar ridge width before surgery was 10.03 mm. After 6 months, the mean alveolar ridge width was 8.4 mm. The range of alveolar ridge width loss was between 0.6 and 3.22 mm with a mean of 1.63 (16.25%). There was no statistically significant difference in width loss between the maxilla and mandibular whether in males or females. Alveolar bone width loss was the greatest at W1 level (26.8%).

Conclusion

According to the results of this study, the authors conclude that the tent-pole technique could preserve the alveolar bone ridge width without bone graft materials.

Evaluation and comparison of three-dimensional finite element analysis of stress distribution in immediately placed and loaded conventional and customized three-dimensional printed dental implants

Aim

The aim of this study was to evaluate and compare the stress distribution patterns in immediately placed and loaded conventional and customized three-dimensional (3D) printed dental implants by 3D finite element analysis.

Materials and Methods

Twelve 3D finite element models [Group A-3 models; Group B-9 models] with 72 test conditions which were modeled and compared from customized 3D printed dental implants [Group A] and 3 commercially available implant systems [Group B] (Straumann, Ankylos, and Astratech) using "SolidWorks". All models were embedded in extraction socket models of the maxillary central incisor (CI) and Canine (C), Mandibular 1st Premolar. An occlusal loading by axial and nonaxial force of 100 N and 150 N at 30° and 45° was applied on the abutment using the "ANSYS" Suite. Customized 3D printed dental implant (Group A) for maxilla (Max.) CI, Max. C, and mandibular 1st premolar (PM) socket model was compared with three commercial available dental implant systems (Group B) for Max. CI, Max. C, and mandible (Mand.) 1st PM socket model to understand the stress distribution patterns.

Results

With increasing oblique loads, von Mises stresses were reduced for the customized group as compared to conventional implants. Increased axial loads caused proportionate increase in the stresses for both groups, yet remained under the physiologic limits in all test conditions. Higher stresses were observed in cortical bone than in cancellous bone at bone-implant contact in general. Marked reduction in von Mises stress was observed at the boundary between compact and cancellous bone. Customized 3D printed implants performed better for oblique loads and comparable for axial load stress distribution in comparison to conventional implant systems in Max. CI and C, Mand. 1st PM.

Conclusion

Thus, customized 3D printed implants appear a promising alternative for immediately placed immediately loaded protocols, with additional benefits in specific clinical situations.

Retrospective analysis of dental implants immediately placed in extraction sockets with periapical pathology: immediate implant placement in infected areas

BACKGROUND

The aim of this study is to examine the survival rates of immediate implants placed in extraction sockets with chronic periapical pathology.

METHODS

69 patients and 124 immediate implants were included in the study. The patients included in the study were examined in 3 groups. Group 1: Patients who underwent tooth extraction with periapical pathology and immediate implant placement. Group 2: patients who underwent tooth extraction with periapical pathology, immediate implant placement and guided bone regeneration. Group 3: Patients who underwent tooth extraction with periapical pathology, sinus lift procedure and immediate implant placement. In statistical analysis, t-test and Anova analysis were used in the evaluation of quantitative data, cross-tables and chi-square (χ2) test were used in the evaluation of classified qualitative data. Statistical significance was determined as p < 0.05.

RESULTS

It was observed that 116 (95.55%) of 124 implants were successful and 8 (4.45%) failed. The success rate was 97.2% in Group 1, 93.5% in Group 2 and 81.8% in Group 3. A significant correlation was found between the study groups and implant success in terms of χ2 test (p = 0.037). A significant relationship was found between smoking and success in terms of the χ2 test (p = 0.015).

CONCLUSIONS

High survival rates are observed for immediate implant placement in sockets with periapical pathology. The success rates observed in guided bone regenerations simultaneously with immediate implant placement are at satisfactory levels. In cases where simultaneous sinus lifting procedures are required, the success rates were observed to be significantly lower. In case of adequate curettage and debridement in sockets with periapical pathology, high implant survival rates are observed. As the complexity of the surgical procedure increases, treatment protocols may progress in safer ways.

Trueness and precision of milled and 3D printed root-analogue implants: A comparative in vitro study

OBJECTIVES

The present study aimed to evaluate the accuracy (trueness and precision) of titanium and zirconia multi-rooted root analogue implants (RAIs) manufactured by milling and 3D-printing.

METHODS

A multi-rooted RAI was designed based on a mandibular second molar segmented from cone-beam computed tomography (CBCT). The manufactured RAIs were divided into four groups: 3D-printed titanium (PT) and 3D-printed zirconia (PZ) (n=10 each), as well as milled titanium (MT) and milled zirconia (MZ) (n=5 each). The specimens were scanned with a high-precision scanner, and the scanned data were imported into 3D-measurement software to evaluate the precision and trueness of each group. Root mean square (RMS) deviations were measured and statistically analysed (One-way ANOVA, Tukey's, p≤0.05).

RESULTS

PZ showed the highest precision with RMS value of 21±6 µm. Nevertheless, there was no statistically significant difference in precision among the other groups. Regarding trueness, MZ showed the highest trueness with RMS value of 66±3 µm, whereas MT showed the lowest trueness result. Inspection sections showed that MT had significantly high RMS deviation in the furcation area (612±64 µm), whereas PZ showed significantly high RMS deviation at the apical area (197±17 µm).

CONCLUSIONS

The manufacturing process significantly influenced the RAI accuracy. PZ exhibited the highest precision, whereas MZ exhibited the highest trueness, followed by PT. Finally, our results suggest that 3D-printing can reproduce concave surfaces and less accessible areas better than milling.

CLINICAL SIGNIFICANCE

Milled and 3D-printed RAIs showed promising results in terms of precision and trueness. However, further clinical research is needed to advocate their use as immediate implants. Additionally, the inherent volumetric changes of the various materials during manufacturing should be considered.

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.

Immediate dental implant placement in post-extraction-infected sites decontaminated with Er,Cr:YSGG laser: a retrospective cohort study

Dental implants placed in fresh extraction alveoli provide several advantages, including shorter treatment periods and improved patient comfort. After a compromised tooth extraction, the Er,Cr:YSGG laser can considerably reduce bacterial concentration. The objective of this controlled study conducted after at least 1 year of follow-up was to compare the use of immediate post-extraction implants in infected sites treated with laser (test group) versus conventional implants in edentulous sites (control group) through an analysis of pre- and post-operative radiographs. The study was based on a series of patients treated between 2014 and 2019, with a 1-year minimum follow-up, and up to over 4 years. An analysis of the clinical history of the treated patients and pre- and post-operative radiographs was performed to evaluate the implant success and to measure the marginal bone level (MBL). Overall, 149 implants were studied. There was only one failure in the test group (1%) and no failures in the control group. The test group gained 0.1 mm of the MBL compared to the baseline, while the control group lost 0.1 mm of the MBL. The difference between the two groups of only 0.2 mm was not statistically significant (P = 0.058). Immediate dental implants in infected sockets debrided and decontaminated using Er,Cr:YSGG laser do not appear to enhance the likelihood of failure; however, peri-implantitis and associated problems must be avoided by following a certain set of protocols and procedures.

Immediate flapless implant placement in a smoker patient: A challenge for optimum aesthetics and secondary stability: A case report

The objective of this case report was to restore the young patient with missing teeth and extruded tooth using an immediate implant and synthetic bone graft material for the esthetic and comfort purpose. A 21-year young man reported extrusion of a tooth as well as missing teeth. Clinical examination revealed missing teeth in relation to (irt) 11 and 21, extrusion of tooth in relation to (irt) 12, patient had generalized fluorosis, and localized marginal gingivitis with melanin pigmentation. The patient is a known smoker, and he was advised the cessation of smoking before the treatment. This paper describes a step-by-step approach to different treatment phases, starting with surgical guide fabrication, immediate implant surgical procedures, bone grafting procedure, and later prosthesis fabrication. Follow-up resulted in a satisfactory outcome.

Immediate, non-submerged, three-dimensionally printed, one-piece mandibular molar porous root-analogue titanium implants: A 2-year prospective study involving 18 patients

This study prospectively evaluated non-submerged, three-dimensionally printed, one-piece molar porous root-analogue titanium implants. A total of 18 non-restorable multiple-rooted teeth in 18 patients, aged 22-64 years, were included in this study. A series of computed tomography images of the mandible were selected and rendered into a digital model. The non-restorable mandibular molars were digitally separated from the surrounding alveolar bone, and served as the template on which the porous root-analogue titanium implants (RAIs) were designed with computer-aided design (CAD) software. The porous molar RAIs were fabricated with the selective laser melting technique (average particle size 20 μm) and inserted into the alveolar sockets after extraction of the non-restorable molars. Definitive restorations were placed after 3 months of uninterrupted healing. Peri-implant clinical and radiographic measurements were obtained 2 years later. All patients functioned well following 2 years of functional loading, and peri-implant clinical and radiographic measurements demonstrated implant stability. No implants were lost at the 2-year follow-up, and the survival rate was 100%. Three-dimensionally printed one-piece molar porous RAIs may be a promising option for the replacement of non-restorable molars that are planned for extraction. Additional studies are required to evaluate the long-term survival of implants fabricated using this technique.

10-Year Evaluation of the First Root Analogue Implant on Humans, Made Using a CT Scan, CAD/CAM and DMLS

Ten years ago, for the first time in humans, thanks to the DLMS (direct metal laser sintering) technique, we designed, built and inserted an immediate post-extraction custom-made root-analogue implant in Ti-6Al-4v with platform switching. The implant was inserted into the post-extraction socket, respecting the biological width. After 10 years, we wanted to evaluate the dimensional stability of the implant and the eventual crestal bone resorption. The evaluation was performed clinically with periodontal parameters and radiographically by means of an intraoral X-ray with the parallel technique measuring the distance between the base of the bone crest and the implant shoulder. It appears that the implant has maintained dimensional stability of the peri-implant soft tissues, and the crestal resorption is 0 mm. This could represent a step forward to make this experimental method a valid alternative to the current immediate post-extraction implant procedures in use.

Immediate Loading of a Fully Tapered Implant with Deep Apical Threads Placed in Healed Alveolar Ridges vs. Immediate Extraction Sockets

OBJECTIVES

Immediate implant placement and loading is a practice that continues to gain traction in implant dentistry because it reduces treatment time and improves satisfaction. Novel implant designs that facilitate increased primary stability, while not compromising osseointegration and long-term survival are important to offer immediate solutions for missing teeth. Here, we hypothesize that fully tapered implants can obtain successful osseointegration with high survival rates after immediate loading in fresh extraction sockets and healed sites.

MATERIALS AND METHODS

13 swine with 73 implants were evaluated. Fully tapered or apically tapered implants were placed in extraction sockets and healed sites. Insertion torque and resonance frequency analysis were determined at placement and euthanasia. Animals were evaluated at: placement, and 1-week and 12-weeks after placement. Bone to Implant Contact (BIC), Bone Area / Total Area (BA/TA), and first BIC (fBIC) analyses was conducted.

RESULTS

The fully tapered implant achieved similar primary stability with lower insertion torque at placement (Fig. 2). Apically and fully tapered implants had comparable BIC (50.1% vs 59.4%) and ISQ (82.5 vs 80.3) values by 12 weeks in healed sites. In extraction sockets, BIC and ISQ for the apically tapered implant was 35.8% and 73.2 and 37.8% and 79.2 for the fully tapered implants, respectively (Fig. 2, 5).

CONCLUSIONS

In this short-term study, immediately loaded fully tapered implants obtained high survival with similar osseointegration ability as apically tapered implants when placed in healed sites and fresh extraction sockets. Fully tapered implants show promise for use in immediate loading and immediate placement.

Multiscale analysis of craniomaxillofacial bone repair: A preclinical mini pig study

BACKGROUND

The rate of reparative osteogenesis controls when an implant is sufficiently stable as to allow functional loading. Using a mini pig model, the rate of reparative osteogenesis in two types of implant sites e.g., an osteotomy versus a fresh extraction socket were compared.

METHODS

Eight adult mini pigs were used for the study. In Phase I, three premolars were extracted on one side of the oral cavity; 12 weeks later, in Phase II, osteotomies were produced in healed extraction sites, and contralateral premolars were extracted. Animals were sacrificed 1, 5, and 12 weeks after Phase II. Bone repair and remodeling were evaluated using quantitative micro-computed tomographic imaging, histology, and histochemical assays coupled with quantitative dynamic histomorphometry.

RESULTS

One week after surgery, extraction sockets and osteotomy sites exhibited similar patterns of new bone deposition. Five weeks after surgery, mineral apposition rates were elevated at the injury sites relative to intact bone. Twelve weeks after surgery, the density of new bone in both injury sites was equivalent to intact bone but quantitative dynamic histomorphometry and cellular activity assays demonstrated bone remodeling was still underway.

CONCLUSION(S)

The mechanisms and rates of reparative osteogenesis were equivalent between fresh extraction sockets and osteotomies. The volume of new bone required to fill a socket, however, was significantly greater than the volume required to fill an osteotomy. These data provide a framework for estimating the rate of reparative osteogenesis and the time to loading of implants placed in healed sites versus fresh extraction sockets. This article is protected by copyright. All rights reserved.

Impact of lattice versus solid structure of 3D-printed multiroot dental implants using Ti-6Al-4V: a preclinical pilot study

Purpose

Various studies have investigated 3-dimensional (3D)-printed implants using Ti-6Al-4V powder; however, multi-root 3D-printed implants have not been fully investigated. The purpose of this study was to explore the stability of multirooted 3D-printed implants with lattice and solid structures. The secondary outcomes were comparisons between the 2 types of 3D-printed implants in micro-computed tomographic and histological analyses.

Methods

Lattice- and solid-type 3D-printed implants for the left and right mandibular third premolars in beagle dogs were fabricated. Four implants in each group were placed immediately following tooth extraction. Implant stability measurement and periapical X-rays were performed every 2 weeks for 12 weeks. Peri-implant bone volume/tissue volume (BV/TV) and bone mineral density (BMD) were measured by micro-computed tomography. Bone-to-implant contact (BIC) and bone area fraction occupancy (BAFO) were measured in histomorphometric analyses.

Results

All 4 lattice-type 3D-printed implants survived. Three solid-type 3D-printed implants were removed before the planned sacrifice date due to implant mobility. A slight, gradual increase in implant stability values from implant surgery to 4 weeks after surgery was observed in the lattice-type 3D-printed implants. The marginal bone change of the surviving solid-type 3D-printed implant was approximately 5 mm, whereas the value was approximately 2 mm in the lattice-type 3D-printed implants. BV/TV and BMD in the lattice type 3D-printed implants were similar to those in the surviving solid-type implant. However, BIC and BAFO were lower in the surviving solid-type 3D-printed implant than in the lattice-type 3D-printed implants.

Conclusions

Within the limits of this preclinical study, 3D-printed implants of double-rooted teeth showed high primary stability. However, 3D-printed implants with interlocking structures such as lattices might provide high secondary stability and successful osseointegration.

Modifying a 3D-Printed Ti6Al4V Implant with Polydopamine Coating to Improve BMSCs Growth, Osteogenic Differentiation, and In Situ Osseointegration In Vivo

Nowadays, 3D printing technology has been applied in dentistry to fabricate customized implants. However, the biological performance is unsatisfactory. Polydopamine (PDA) has been used to immobilize bioactive agents on implant surfaces to endow them with multiple properties, such as anti-infection and pro-osteogenesis, benefiting rapid osseointegration. Herein, we fabricated a PDA coating on a 3D-printed implant surface (3D-PDA) via the in situ polymerization method. Then the 3D-PDA implants' pro-osteogenesis capacity and the osseointegration performance were evaluated in comparison with the 3D group. The in vitro results revealed that the PDA coating modification increased the hydrophilicity of the implants, promoting the improvement of the adhesion, propagation, and osteogenic differentiation of bone marrow-derived mesenchymal stem cells (BMSCs) in vitro. Additionally, the 3D-PDA implant improved osteointegration performance in vivo. The present study suggested that PDA coating might be a feasible strategy to optimize 3D-printed implant surfaces, making a preliminary research basis for the subsequent work to immobilize bioactive factors on the 3D-printed implant surface.

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.

Immediate Implant Placement and Provisionalization in the Esthetic Zone: A 6.5-Year Follow-Up and Literature Review

The success of dental implant therapy in the esthetic zone requires not only functional osseointegration but also a satisfactory esthetic outcome. To establish harmony, balance, and continuity of gingival architecture between an implant restoration and the adjacent natural dentition is challenging. Immediate implant placement and provisionalization following tooth extraction have been documented as a predictable treatment modality, with fewer surgical interventions needed, to replace a missing tooth in the esthetic zone. This case report illustrates immediate implant placement and provisionalization to replace a failing maxillary right central incisor while maintaining optimal gingival esthetics. The maxillary right central incisor was extracted without flap elevation to minimize soft and hard tissue trauma. Immediately afterwards, the implant was installed using a surgical stent and restored with a provisional crown that had no occlusal contacts. During healing, no significant adverse effects were observed clinically or radiographically. This proposed treatment modality provided the patient with immediate esthetics, function, and comfort without any complications during a follow-up period of 6.5 years.

Immediate implant placement following tooth extraction with simultaneous lateral sinus augmentation: a retrospective clinical study after at least 1 year of loading

Background

Lateral sinus augmentation is necessary when the residual bone height is insufficient in the posterior maxilla. Immediate implant placement following tooth extraction with lateral sinus augmentation will shorten the number of operations and treatment time.

Purpose

To evaluate radiologic and clinical results for at least 1 year after loading in patients who underwent tooth extraction, implant placement, and lateral sinus augmentation at the same time.

Materials and methods

We retrospectively evaluated 35 implants placed in 25 patients. Preoperative and postoperative CBCT were compared and analyzed for residual bone height (RBH) and increased bone height (IBH), the initial torque value (ITV), and the implant stability quotient (ISQ). A comparative evaluation was performed between a 1-stage (non-submerged) group and a 2-stage (submerged) group. After loading for at least 1 year, clinical and radiological evaluations were performed to evaluate the survival rate.

Results

One of the 35 implants failed in osseointegration, and the remaining 34 showed successful results. The failure-free survival rate at 1 year was 97.06% (95% CI, 91.38-100.0%). The RBH ranged from 3.1 to 9.6 mm (mean, 5.62 ± 1.68 mm), and the IBH ranged from 3 to 15.3 mm (mean, 8.87 ± 2.74 mm). Among the RBH, ITV, ISQ, treatment period, final bone height, and failure evaluation by stage of implant placement, only ISQ showed statistical significance between the groups (p < .001). A comparison of RBH, ITV, and ISQ, regardless of group, showed that each value tended to increase, but there were no statistically significant differences.

Conclusions

Immediate implant placement following tooth extraction with simultaneous lateral sinus augmentation is considered reliable even though the procedures had been performed at the same time.

Immediate implant placement and loading in the esthetic area when the buccal socket wall is significantly damaged

OBJECTIVES

Recent clinical recommendations contraindicate immediate implant placement when the socket buccal bone plate is significantly damaged. The connective tissue graft (CTG) is increasingly being used in implant therapy and can replace periodontal defects lacking bone wall in periodontal regenerative surgery. Therefore, CTG could be used to allow immediate implant placement and loading even when the buccal socket wall is damaged, facilitating graft material stability.

CLINICAL CONSIDERATIONS

In the first case, deep bone dehiscence was caused by a vertical root fracture. In the second case, a big bone fenestration was caused by a chronic endodontic periapical lesion. Both cases were treated with immediate implant placement and loading. A buccal CTG was used to compensate for the lack of bone and allow stabilization of the particulate xenograft in the gap between the implant and the damaged buccal socket wall. In both cases, a provisional screw-retained crown was immediately delivered, and the definitive layered zirconia crown was delivered after 3 months. Esthetic results and patient satisfaction monitored for 1 year after loading proved to be encouraging.

CONCLUSIONS

Although further investigations with longer follow-up are required, the approach is likely to yield good results after 1 year of loading.

CLINICAL SIGNIFICANCE

The purpose of this report is to show a surgical approach that seems to be able to overcome the contraindication of the quoted consensus report, which allows for good esthetic results and patient satisfaction even when the buccal bone wall of the extraction socket has been more than 50% compromised, allowing treatment time and cost reduction.

Histological and Radiological Features of a Four-Phase Injectable Synthetic Bone Graft in Guided Bone Regeneration: A Case Report

BACKGROUND AND OBJECTIVE

Injectable synthetic bone grafts (ISBG) are widely used biomaterials for regeneration purposes. The aim of this case report was to examine the efficacy of ISBG in the management of buccal fenestration in the case of a 25-year-old female.

CASE REPORT

After a traumatic tooth extraction, the defect was filled with ISBG and covered with a resorbable membrane. The ISBG showed easy handling and the patient had no complications during healing. Six months after augmentation, a bone biopsy was taken during implant bed preparation. The histological results showed good integration of ISBG into the newly formed bone and no signs of tissue inflammation. Additionally, a CBCT (cone beam computed tomography) analysis was performed to support the histological results.

CONCLUSION

The use of the examined ISBG led to successful treatment of the buccal fenestration defect.

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.

Antibacterial and Osteogenic Functionalization of Titanium With Silicon/Copper-Doped High-Energy Shot Peening-Assisted Micro-Arc Oxidation Technique

Antibacterial and osteogenic functionalization of titanium (Ti) implants will greatly expand their clinical indications in immediate implant therapy, accelerate osteointegration, and enhance long-term prognosis. We had recently shown that the high-energy shot peening (HESP)-assisted micro-arc oxidation (MAO) significantly improved the bioactivity and coating stability of Ti-based substrates. In this study, we further functionalized Ti with antibacterial and osteogenic properties by doping silicon (Si) and/or copper (Cu) ions into HESP/MAO-treated coatings. Physicochemical characterization displayed that the doping of Si and Cu in HESP/MAO-treated coatings (Si/Cu-MAO) did not significantly change their surface topography, roughness, crystal structure, coating thickness, bonding strength, and wettability. The results of X-ray photoelectron spectroscopy (XPS) showed that Si and Cu in the Si/Cu-MAO coating was in the form of silicate radical (SiO₃ ^2-) and bivalent copper (Cu²⁺), respectively. The total amounts of Si and Cu were about 13.5 and 5.8 μg/cm², which released about 33.2 and 31.3% within 14 day, respectively. Compared with the control group (MAO), Si doping samples (MAO-Si) significantly increased the cell viability, alkaline phosphatase (ALP) activity, mineralization and osteogenic genes (ALP, collagen I and osteocalcin) expression of MC3T3-E1 cells. Furthermore, the addition of Cu presented good bactericidal property against both Staphylococcus aureus and Streptococcus mutans (even under the co-culture condition of bacteria and MC3T3-E1 cells): the bacteriostatic rate of both bacteria was over 95%. In conclusion, the novel bioactive Si/Cu-MAO coating with antibacterial and osteogenic properties is a promising functionalization method for orthopedic and dental implants, especially in the immediate implant treatment with an infected socket.

Studies on the Performance of Molar Porous Root-Analogue Implant by Finite Element Model Simulation and Verification of a Case Report

PURPOSE

The aim of this study was to evaluate the effect of porous layer thickness in a 3-dimensionally printed 1-piece molar porous root-analogue implant (RAI) on the biomechanical properties of the peri-implant bone and the clinical efficacy of one such implant in a patient.

MATERIALS AND METHODS

Three RAIs with different superficial porous layer thicknesses (0.5 mm, 1 mm, and fully porous) were designed and assembled using a mandible model and then solidified to obtain 3 finite elements models, denoted A, B, and C. Finite element analysis was performed to analyze the stress on the solid and porous structures of the RAIs and the stress and strain experienced by the bone surrounding the implant. RAIs were fabricated by selective laser melting. An unrepairable molar in a single patient was selected for replacement. An RAI was designed and prepared and then implanted into the alveolar bone immediately after minimally invasive extraction of the damaged tooth. Definitive restorations were placed after a 3-month period of uninterrupted healing.

RESULTS

The stress concentration observed in the 3 types of RAI was principally between the solid and porous interface contact points, with maximum stress on the solid and porous structures smaller than that of the respective yield strength. The introduction of a porous structure on the surface of the RAIs increased peri-implant bone stress, which increased with thickness of the porous layer. The 3-dimensionally printed porous RAI exhibited excellent initial stability immediately after implantation. After continual observation for 6 months, it was found that bone surrounding the root had infiltrated into the RAI, achieving good osseointegration.

CONCLUSIONS

Stress shielding can be reduced by decreasing the elastic modulus of the implant, with the interface between implant and bone allowing more appropriate stress conduction. A 1-piece porous RAI fabricated using 3-dimensional printing establishes a new indication for immediate implantation after extraction.

Rationale for a reverse tapered body shift implant for immediate placement

Immediate implant placement holds considerable value, yet primary implant stability is often a critical factor. The aim of this study was to evaluate the stability, volumetric viability, and buccal gap size of reverse tapered body shift (RTBS) implants after immediate placement. Peak insertion torque measurements of two RTBS designs (apical 40% vs. apical 50%), relative to conventionally tapered implants, were assessed in simulated extraction sockets prepared in synthetic bone blocks. Additionally, the proximity of the RTBS implants to neighbouring teeth and anatomical structures, and the buccal gap distance were evaluated in human cadavers. The mean (± standard deviation) insertion torque was 12.00±1.40N•cm for the conventionally tapered implants (n=50), 35.36±2.74N•cm (n=50) for RTBS-1, and 48.20±2.90N•cm (n=50) for RTBS-2; the difference between designs was statistically significant (P<0.01). In total, 40 RTBS implants (20 per design) were placed in six cadaveric premaxillae. Only one locus was inappropriate for both RTBS implant designs, due to the proximity of neighbouring teeth. The average buccal gap for both implant designs was 2.8mm (P=0.104). The improved primary stability and increased buccal gap size with RTBS implants may enhance the feasibility of immediate placement. The study findings should be further validated in clinical trials.

Immediate Implant Placement in Infected Sockets: A Consecutive Cohort Study

Introduction: Immediate placement of implants in a fresh post-extraction socket is an increasingly popular and established treatment option. However, active infection in the extraction site may adversely affect the outcome of this procedure. This study was designed to assess the clinical results of immediate placement of dental implants in infected extraction sockets using a standardized protocol, which included (a) the use of an Er,Cr:YSGG laser for the decontamination of the infected socket prior to implant insertion, and (b) the utilization of an in situ hardening alloplastic bone graft substitute to augment the gap between the implant surface and the labial plate of bone. Patients and Methods: A retrospective record review was used to identify 68 patients who had implants placed as per the described protocol. A total of 126 implants were placed in 68 patients (65 implants in the maxilla, 61 implants in the mandible). The implants were loaded 136 ± 73 days (mean ± standard deviation; range: 37–400 days) after implant placement. Eight patients (16 implants) were subsequently lost to follow up. Results: 105 of the 110 implants (95.45%) placed immediately in the infected sites using the described protocol survived after prosthetic loading. Conclusion: Immediate implant placement in previously infected sites using the protocols mentioned in our study with laser decontamination of the socket, grafting with an in situ hardening alloplastic bone graft material and non-submerged healing shows a similar survival rate to the published success rates for immediate implants placed in non-infected sites.

Allograft and Collagen Membrane Augmentation Procedures Preserve the Bone Level around Implants after Immediate Placement and Restoration

Background: Immediate implant placement and restoration (IPR), is a reliable treatment modality. Purpose: This historical prospective study evaluated the medium-term outcomes of hard tissue after IPR in the anterior maxilla with simultaneous hard tissue augmentation. Methods: Seventy-three patients treated with single-implant IPR in the anterior maxilla were followed for 1-8 years. Treatment involved, atraumatic extraction, immediate implant placement and abutment adaptation, followed by simultaneous augmentation with mineralized freeze-dried bone allograft (FDBA) particles to fill the gaps and restore the ridge. The surgical site was stabilized with a resorbable collagen membrane, followed by the connection of an acrylic provisional restoration. Results: All implants osseointegrated during the follow-up period (mean, 34 ± 22 months). Radiographic evaluation of the distance between the implant shoulder (IS) and crestal bone level (CBL) was of 0.86 ± 0.86 mm and 0.8 ± 0.84 mm mesially and distally, respectively. Splitting the results into up to 3 years and 3-8 years of follow-up data, the corresponding values were 0.90 ± 0.83 and 0.68 ± 0.88 for the mesial aspect and 0.99 ± 0.87and 0.74 ± 0.83 for the distal aspect, respectively. Mean peri-implant probing depth was 3.63 mm (SD ± 1.06) and 16 implants (22%) presented at least one bleeding pocket of ≥5 mm (peri implant mucositis). Conclusions: The immediate replacement of a single maxillary tooth by implants combined with guided bone regeneration is a predictable treatment modality with favorable peri-implant bony response.

A 22-Year Follow Up of Immediate Implant Placement without Bone Augmentation: A Case Series Study

PURPOSE

To retrospectively evaluate the treatment outcome of immediate implants placed in fresh extraction sockets without bone augmentation after 22 years of function.

MATERIALS AND METHODS

The study group received implant therapy in 1997, including surgical placement and prosthodontic rehabilitation. The mean age of the subjects at the time of implant placement was 40 ± 5.54 years. A total of 35 subjects received 36 implants in fresh extraction sockets without bone augmentation. Definitive prostheses were placed 4 to 6 months after implant placement. Implant treatment outcomes were evaluated using clinical and radiographic parameters obtained during follow-up visits at 1, 5, 10, 15, 20, and 22 years after prosthetic loading.

RESULTS

Among the 35 treated subjects, five patients moved out of the country and could not be evaluated at the follow-up times. A total of 29 subjects were included in the study with a drop-out rate of 14.1%. Of these, one patient lost the implant during the osseointegration period before prosthodontic treatment. No other implant failure or complication during the rest of the follow-up period was reported, thus giving a cumulative survival rate of 97.2% during the 22-year follow-up. The change in marginal bone level was less than 2 mm in most subjects at the 22-year examination. The mean bone loss from baseline to 22-year follow-up was 1.61 mm, and the mean bone level at the 22-year follow-up examination was situated at 2.13 ± 0.023 mm from the implant platform, which was used as the reference point.

CONCLUSIONS

Immediate implant placement in extraction sockets exhibits excellent prognosis even when bone augmentation is not performed.

Augmentation versus No Augmentation for Immediate Postextraction Implants

Purpose

To assess the effects of augmentation versus no augmentation in patients restored with immediate postextraction single-tooth implants on implant failure and patient satisfaction.

Materials and methods

We searched the Cochrane Oral Health Group Trial Register, Cochrane Central Register of Controlled Trials, MEDLINE, and the WHO International Clinical Trial Registry Platform (22 March 2017). Two reviewers independently assessed trials for inclusion and risk of bias, extracted data, and checked for accuracy. We have expressed results as risk ratio or mean differences, together with their 95% confidence intervals.

Results

We included six studies (287 participants). Two trials compared no augmentation versus bone graft augmentation and reported no implant failures in both groups after a follow-up period of 6 months (20 implants) and 1 year (34 implants). One trial compared bone graft augmentation versus membrane augmentation and reported no difference in implant failure between both groups after 6 months (risk ratio (RR) 0.98, 95% confidence interval (CI) 0.06 to 15.31) or 1 year of follow-up (RR 0.33, 95% CI 0.01 to 7.86), and no implants were lost after 3 years. Three trials compared membrane augmentation versus combined bone graft and membrane augmentation, and there was no difference between the groups after six months of follow-up in implant failure (RR 5.13, 95% CI 0.63 to 41.93) or after 1 year (RR 0.38, 95% CI 0.02 to 9.05). There was insufficient evidence regarding patient satisfaction in all the included trials.

Conclusions

In patients restored with immediate postextraction single-tooth implants, there is insufficient evidence to recommend simultaneous augmentation or a certain augmentation protocol to enhance implant survival and patient satisfaction. This trial is registered with PROSPERO (CRD42017054439).

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.

Effect of Microthread Design on Marginal Bone Level Around Dental Implants Placed in Fresh Extraction Sockets

PURPOSE

This study was designed to compare radiographically the effect of microthread on the coronal portion of the fixture on marginal bone level (MBL) around immediately placed dental implants in human subjects.

MATERIAL AND METHODS

Forty-one roughened surface screw type Dentium oral implants (Dentium) were inserted in fresh extraction sockets of the anterior segment of maxilla of 30 patients. The implants were selected randomly using either microthread design on coronal portion of the fixture (Implantium) (test group) or without microthread thread design (Superline) (control group). MBL was measured using digital subtraction radiography technique after 3, 6, and 12 months.

RESULTS

At month 3, the microthread groups have been associated with more marginal bone loss than the control group (P = 0.04). At months 6 and 12, both groups had comparable bone levels (P = 0.21).

CONCLUSION

The microthread design of the implant collar could not have a positive effect in maintaining the MBL around implants placed in fresh extraction socket in anterior maxilla.

Mathematical evaluation of the influence of multiple factors on implant stability quotient values in clinical practice: a retrospective study

Objectives

The objective of this study is to mathematically evaluate the influence of multiple factors on implant stability quotient values in clinical practice.

Patients and methods

Resonance frequency analysis was performed at T1 (measured immediately at the time of implant placement) and at T2 (measured before dental restoration) in 177 patients (329 implants). Using a multivariate linear regression model, we analyzed the influence of the following eleven candidate factors: sex, age, maxillary/mandibular location, bone type, immediate/delayed implantation, bone grafting (presence or absence), insertion torque, I-/II-stage healing pattern, implant diameter, implant length, and T1–T2 time interval.

Results

The following factors were identified to significantly influence the implant stability quotient (ISQ) values at T1: insertion torque, bone grafting, I-/II-stage healing pattern, immediate/delayed implantation, maxillary/mandibular location, implant diameter, and sex. In contrast, the ISQ values at T2 were significantly influenced only by three factors: implant diameter, T1–T2 time interval, and insertion torque.

Conclusion

Among the eleven candidate factors, seven key factors were found to influence the T1-ISQ values, while only three key factors influenced the T2-ISQ values. Both T1 and T2-ISQ values were found to be influenced by implant diameter and insertion torque. T1 was influenced specifically by the sex of the patient, the location (maxillary or mandibular), the implantation mode (immediate/delayed implantation), the healing stage, and the absence or presence of bone graft materials.

Clinical and histological evaluation of socket grafting using different types of bone substitute in adult patients

PURPOSE

This clinical and histological study evaluated the healing of extraction sockets after implantation of a biphasic calcium sulfate (CS) alone or in combination with a gamma-radiated human mineralized allograft.

MATERIALS AND METHODS

Ten healthy adult patients participated in the study. A minimum of 2 teeth, per patient, extracted for different reasons were evaluated. Each socket was randomly filled to the crest with either (a) a biphasic CS or (b) large particulate gamma-radiated human mineralized allograft in combination with a biphasic CS.

RESULTS

No complications during reentry of the socket site during bone core retrieval, such as inflammation/immunogenic response, were observed. Histological findings showed a mean new bone (NB) of 33% for sockets filled with biphasic CS and 31% for sockets filled with biphasic CS in combination with allograft material. There was no statistically significant difference in the percentage of NB and the presence of soft tissue between graft materials.

CONCLUSION

Biphasic CS used alone or in combination with an allograft resulted in the same amount of NB formation in alveolar ridge preservation procedures.

Aesthetic outcome of immediately restored single implants placed in extraction sockets and healed sites of the anterior maxilla: a retrospective study on 103 patients with 3 years of follow-up

OBJECTIVES

The aim of this study was to compare the aesthetic outcome of single implants in extraction sockets and healed ridges of the anterior maxilla by means of the pink aesthetic score/white aesthetic score (PES/WES) index.

MATERIALS AND METHODS

This retrospective study was based on data from 103 patients (43 males, 60 females) aged 24-65 years (mean age 41.4 ± 13.8 years) who had been successfully treated with a single implant in the anterior maxilla, in four different clinical centres. Forty-two patients (mean age 46.5 ± 15.1 years) were treated with a single implant in a fresh post-extraction socket (immediate implant treatment, IIT), while 61 patients (mean age 38.0 ± 11.8 years) were treated with a single implant in a healed site (conventional implant treatment, CIT). Two independent calibrated examiners applied the PES/WES index to the 103 single-tooth restorations, respectively 3 months and 3 years after implant placement.

RESULTS

A few biological (4.8%) and prosthetic (8.7%) complications were reported. Both IIT and CIT yielded satisfactory aesthetic outcomes. At the delivery of the final restoration, a PES/WES score of 16.6 ± 2.6 and 15.7 ± 3.0 was reported for IIT and CIT, respectively: this difference was not statistically significant. A higher decrease in the PES/WES score was observed with CIT over time. At 3 years, a PES/WES score of 16.4 ± 2.8 and 15.2 ± 3.3 was reported for IIT and CIT, respectively: this difference was statistically significant. IIT seemed to yield better aesthetic outcomes in young patients (≤30 years), with implants placed in central incisor/cuspid areas, in the presence of bone contouring.

CONCLUSIONS

Both immediate and conventional single-implant treatment in the anterior maxilla can yield satisfactory aesthetic outcomes, when performed by experienced clinicians in well-selected cases. Further studies are needed to confirm these results.

Protocol for Bone Augmentation with Simultaneous Early Implant Placement: A Retrospective Multicenter Clinical Study

Purpose. To present a novel protocol for alveolar bone regeneration in parallel to early implant placement. Methods. 497 patients in need of extraction and early implant placement with simultaneous bone augmentation were treated in a period of 10 years. In all patients the same specific method was followed and grafting was performed utilizing in situ hardening fully resorbable alloplastic grafting materials consisting of β-tricalcium phosphate and calcium sulfate. The protocol involved atraumatic extraction, implant placement after 4 weeks with simultaneous bone augmentation, and loading of the implant 12 weeks after placement and grafting. Follow-up periods ranged from 6 months to 10 years (mean of 4 years). Results. A total of 601 postextraction sites were rehabilitated in 497 patients utilizing the novel protocol. Three implants failed before loading and three implants failed one year after loading, leaving an overall survival rate of 99.0%. Conclusions. This standardized protocol allows successful long-term functional results regarding alveolar bone regeneration and implant rehabilitation. The concept of placing the implant 4 weeks after extraction, augmenting the bone around the implant utilizing fully resorbable, biomechanically stable, alloplastic materials, and loading the implant at 12 weeks seems to offer advantages when compared with traditional treatment modalities.

Morphometric analysis of maxillary alveolar regions for immediate implantation

PURPOSE

The purpose of this study was to provide an actual guideline in determining the shape, diameter, and position of the implant in immediate implantation by the measurement of the thickness of facial and palatal plate, the thickness of cortical bone on the facial and palatal plate, the diameter of the root, and the distance between the roots in the cadavers.

MATERIALS AND METHODS

The horizontal sections of 20 maxillae were measured and analyzed to obtain the average values. Resin blocks were produced and cut serially at 1 mm intervals from the cervical line to the root apex. Images of each section were obtained and the following measurements were performed: The thickness of the facial and palatal residual bone at each root surface, the thickness of the facial and palatal cortical bone at the interdental region, the diameter of all roots of each section on the faciopalatal and mesiodistal diameter, and the interroot distance. Three specimens with measurements close to the average values were chosen and 3-dimensional images were reconstructed.

RESULTS

The thickness of the facial and palatal cortical bone at the interdental region in the maxilla, the buccal cortical bone was thicker in the posterior region compared to the anterior region. The interroot distance of the alveolar bone thickness between the roots increased from anterior to posterior region and from coronal to apical in the maxilla.

CONCLUSION

In this study, the limited results of the morphometric analysis of the alveolar ridge using the sections of maxilla in the cadavers may offer the useful information when planning and selecting optimal implant for immediate implantation in the maxilla.

Measurement of primary and secondary stability of dental implants by resonance frequency analysis method in mandible

Background. There is no doubt that the success of the dental implants depends on the stability. The aim of this work was to measure the stability of dental implants prior to loading the implants, using a resonance frequency analysis (RFA) by Osstell mentor device. Methods. Ten healthy and nonsmoker patients over 40 years of age with at least six months of complete or partial edentulous mouth received screw-type dental implants by a 1-stage procedure. RFA measurements were obtained at surgery and 1, 2, 3, 4, 5, 7, and 11 weeks after the implant surgery. Results. Among fifteen implants, the lowest mean stability measurement was for the 4th week after surgery in all bone types. At placement, the mean ISQ obtained with the magnetic device was 77.2 with 95% confidence interval (CI) = 2.49, and then it decreased until the 4th week to 72.13 (95% CI = 2.88), and at the last measurement, the mean implant stability significantly (P value <0.05) increased and recorded higher values to 75.6 (95% CI = 1.88), at the 11th week. Conclusions. The results may be indicative of a period of time when loading might be disadvantageous prior to the 4th week following implant placement. These suggestions need to be further assessed through future studies.

Esthetic Evaluation of Single-Tooth Morse Taper Connection Implants Placed in Fresh Extraction Sockets or Healed Sites

The aim of this study was to compare the esthetic outcome of single implants placed in fresh extraction sockets with those placed in fully healed sites of the anterior maxilla. This retrospective study was based on data from patients treated with single-tooth Morse taper connection implants placed in fresh extraction sockets and in fully healed sites of the anterior maxilla. Only single implant treatments were considered with both neighboring teeth present. Additional prerequisites for immediate implant treatment were intact socket walls and a thick gingival biotype. The esthetic outcome was objectively rated using the pink esthetic/white esthetic score (PES/WES). The Mann-Whitney U test was used to compare the PES and the WES between the 2 groups. Twenty-two patients received an immediate implant, and 18 patients had conventional implant surgery. The mean follow-up was 31.09 months (SD 5.57; range 24–46) and 34.44 months (SD 7.10; range 24–48) for immediately and conventionally inserted implants, respectively. No implants were lost. All implants fulfilled the success criteria. The mean PES/WES was 14.50 (SD 2.52; range 9–19) and 15.61 (SD 3.20; range 8–20) for immediately and conventionally placed implants, respectively. Immediate implants had a mean PES of 7.45 (SD 1.62; range 4–10) and a mean WES of 7.04 (SD 1.29; range 5–10). Conventional implants had a mean PES of 7.83 (SD 1.58; range 4–10) and a mean WES of 7.77 (SD 1.66; range 4–10). The difference between the 2 groups was not significant. Immediate and conventional single implant treatment yielded comparable esthetic outcomes.