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

Accuracy analysis of robotic-assisted immediate implant placement: A retrospective case series

OBJECTIVES

This study aimed to investigate the accuracy of a robotic computer-assisted implant surgery (r-CAIS) for immediate implant placement.

METHODS

Patients requiring immediate implant placement in the maxillary anterior region were enrolled for r-CAIS. Before surgery, the patients underwent a cone beam computed tomography (CBCT) scan with a positioning marker. Virtual implant placement position and drilling sequences were planned. Following spatial registration and calibration, the implants were placed with the robotic system under supervision. A postoperative CBCT was taken to control the actual implant positions. The DICOM data of the virtually planned and the actually placed implant were superimposed and registered through the accuracy verification software of the robotic system. The accuracy was calculated automatically. The deviation at the mesial-distal, labial-palatal, and apico-coronal directions were recorded.

RESULTS

Fifteen patients with 20 implants were included. No adverse surgical events or postoperative complications were reported. The global platform, apex, and angular deviation were 0.75 ± 0.20 mm (95 % CI: 0.65 to 0.84 mm), 0.70 ± 0.27 mm (95 % CI: 0.57 to 0.82 mm), and 1.17 ± 0.73° (95 % CI: 0.83 to 1.51°), respectively. Moreover, the vertical platform and apex deviation were 0.50 ± 0.31 mm, (95 % CI: 0.35 to 0.64 mm) and 0.48 ± 0.32 mm, (95 % CI: 0.33 to 0.63 mm), respectively. All the placed implant positions were further labial and apical than the planned ones, respectively.

CONCLUSIONS

High accuracy of immediate implant placement was achieved with the robotic system.

CLINICAL SIGNIFICANCE

Our study provided evidence to support the potential of the robotic system in implant placement, even in challenging scenarios.

Bone alteration and esthetics associated with implant-supported prostheses in the anterior maxilla under different implant placement timing: A retrospective clinical study of 1 to 3 years

STATEMENT OF PROBLEM

Different factors influence alterations in facial bone thickness and esthetic outcomes after implant placement. Whether the timing of implant placement influences alterations in the bone dimensional and esthetic outcomes is unclear.

PURPOSE

The purpose of this retrospective clinical study was to assess the influence of the timing of implant placement on alveolar bone alterations and esthetic outcome.

MATERIAL AND METHODS

Data were collected from 40 patients who had received guided bone regeneration (GBR) performed simultaneously with immediate, early, or delayed single-tooth implant placement in the anterior maxilla. Facial and palatal horizontal bone thicknesses (FHBT, PHBT) and vertical bone level (FVBL, PVBL) immediately after surgery (T0), at 6 months after implant placement (T1), and at 1 to 3 years follow-up (T2) were measured, and the changes calculated. The pink esthetic score (PES) and white esthetic score (WES) were evaluated at the 1- to 3-year follow-up. The Kruskal-Wallis followed by the Dunn t test was applied to evaluate bone alteration among groups, and the Bonferroni method was used for adjusting multiple comparisons. The 1-way ANOVA test was used to determine any significance in the esthetic outcome in the 3 groups (α=.05).

RESULTS

The reduction in the FHBT0 of the immediate, early, and delayed implant placement group (T2-T0) was -1.17 (-1.70, -0.61) mm, -1.53 (-1.69, -0.49) mm, and -1.47 (-2.30, -0.20) mm, respectively. The FHBT around the implant apices remained basically stable. No obvious changes in the PHBT around the implants of the immediate and delayed implant placement group were noted. The FVBL significantly decreased in each group during the follow-up period (-1.34 (01.88, -0.56) mm, immediate; -2.88 (-3.79, -1.07) mm, early; -1.26 (-2.52, -0.48) mm, delayed). The PVBL change in the early implant placement group (-2.18 (-3.26, -0.86) mm) was more significant than that in the immediate (-0.55 (-2.10, -0.17) mm) and delayed (-0.51 (-1.29, 0.02) mm) implantation groups (P =.013). The mean ±standard deviation PES/WES score of the immediate (15.6 ±1.84) and early (15.00 ±1.13) implant placement groups was higher than that of the delayed implant placement group (13.92 ±2.10) without significant difference.

CONCLUSIONS

Similar bone changes and esthetic outcomes were found around implants of the immediate, early, and delayed implant placement groups.

Assessment of crestal bone loss and periodontal parameters of polymer infiltrated ceramic network versus lithium disilicate implant hybrid abutment crowns in the esthetic zone (A randomized clinical trial)

BACKGROUND

Lithium disilicate can be reliable when restoring implants in the esthetic zone. However, it has a high elastic modulus. This might increase the amount of forces transmitted to the crestal bone.

AIM OF THE STUDY

To evaluate the crestal bone loss and peri-implant periodontal parameters of polymer infiltrated ceramic network compared to lithium disilicate implant-supported hybrid abutment crowns after 12 months of follow-up.

METHODOLOGY

44 patients were enrolled. They were randomly assigned into two groups (n = 22). The first group received 22 implants restored with polymer-infiltrated ceramic network (Vitaenamic) hybrid abutment crowns. The second group received 22 implants restored with lithium disilicate (e.max) hybrid abutment crowns over immediately placed implants in the esthetic zone. Periapical radiographs were taken immediately after prosthetic placement and 1 year later utilizing a parallel technique, to assess crestal bone loss. Periodontal parameters were assessed after 1 year.

RESULTS

Regarding crestal bone loss, a comparison between group I (Vitaenamic) and group II (e.max) was made by using an Independent t-test, which showed an insignificant difference between them (p > 0.05). A comparison between groups I and II revealed insignificant differences regarding periodontal parameters (probing depth, bleeding on probing, visible plaque, and suppuration).

CONCLUSIONS

Regarding bone stability and periodontal parameters, polymer infiltrated ceramic network and lithium disilicate hybrid abutment crowns showed comparable results. Both materials showed clinically acceptable hard and soft tissue responses.

Accuracy in static guided implant surgery: Results from a multicenter retrospective clinical study on 21 patients treated in three private practices

PURPOSE

To evaluate the accuracy of a static computer-assisted implant surgery (s-CAIS) system across different private practices.

METHODS

This retrospective clinical study was based on data retrieved from 21 patients who received 61 implants between 2018 and 2020 in 3 private practices run by surgeons with extensive experience with s-CAIS. All patients were treated using the same s-CAIS system, planning software, template manufacturing process, and surgical guides. The standard tessellation language (STL) file of the intraoral scan of the fixture taken immediately after implant placement was matched with that of the preoperative plan for comparisons of preoperative and planned implant positions with postoperative and actual implant positions. The study outcomes were linear and angular deviations between the planned and actual implant positions.

RESULTS

No surgical or postsurgical complications occurred. The overlap of the two STL files resulted in a mean angular deviation of 2.94° The mean linear deviation at the implant shoulder was 0.73 mm, and that at the apex was 1.06 mm. The mean vertical deviations at the implant shoulder and the apex were 0.29 mm and 0.01 mm, respectively.

CONCLUSION

All cases showed satisfactory accuracy within the limits of this study (small number of patients and retrospective design). These results might be related to the use of a standardized digital workflow by experienced operators.

STATEMENT OF CLINICAL RELEVANCE

The study shows that careful control of each step, from data acquisition to final execution, is key for the accuracy of stent-guided systems.

Accuracy of freehand versus guided immediate implant placement: A randomized controlled trial

PURPOSE

This randomized controlled trial (RCT) aimed to compare the accuracy of immediate implant placement with freehand and static guided surgery.

METHODS

An RCT was conducted on 61 subjects who received a total of 80 dental implants. The enrolled patients were randomly allocated to two groups: freehand surgery (control group, n = 40 implants) and static guided surgery with R2Gate® (Megagen, Gyeongbuk, South Korea, test group, n = 40 implants). Crestal and apical deviations in both mesiodistal and buccolingual dimensions, as well as depth and angular deviations, were calculated by comparing the three-dimensional (3D) position of the implant in the planning software with the final implant position, revealed by an intraoral scan of the fixture after placement. The Mann-Whitney test was used for comparative assessment.

RESULTS

In the freehand group (control), crestal deviations of 1.13 ± 0.89 mm and 1.00 ± 0.76 mm were found in the mesiodistal and buccolingual directions, respectively, versus 0.34 ± 0.26 mm (p<0.001) and 0.37 ± 0.24 mm (p = 0.03) in the static guided surgery group (test). Apical deviation was also higher in the freehand group (control) than in the static guided surgery group (test) in the mesiodistal (4.04 ± 1.90 mm vs. 0.97 ± 0.55 mm, p = 0.04) and buccolingual directions (3.46 ± 1.82 mm vs. 0.94 ± 0.67 mm, p = 0.02). Freehand surgery had greater angular deviation (6.09° ± 3.23) compared to guided surgery (0.83° ± 0.53, p = 0.02). However, depth deviation was similar in the freehand surgery group (2.24 ± 1.58 mm) and static guided surgery group (0.66 ± 0.43, p = 0.09).

CONCLUSIONS

Immediate implant placement with static guided surgery demonstrated better accuracy than freehand surgery.

STATEMENT OF CLINICAL RELEVANCE

Guided implant surgery showed fewer deviations compared to freehand surgery in fresh extraction sockets; therefore, the use of static guides should be given preference over the freehand modality.

Clinical performance of immediately placed and immediately loaded single implants in the esthetic zone: A systematic review and meta-analysis

OBJECTIVES

The aim of this study was to assess the following PIO question: In adult patients treated with an indication for single tooth extraction in the maxillary esthetic zone (15-25), what is the influence of an immediate implant placement and immediate loading protocol on the clinical performance (primary aim) and esthetic outcomes (secondary aim) focusing on investigations published after 2010.

MATERIAL AND METHODS

An electronic search in Medline (PubMed), the Cochrane Central Register of Controlled Trials, and EMBASE databases up to April 2022 was performed to identify clinical studies investigating the outcome of single implants subjected to immediate placement with immediate restoration/loading (Type 1A).

RESULTS

Sixty-three studies (10 randomized controlled trials, 28 prospective and 25 retrospective cohort studies) were included with a follow-up ranging from 12 to 96 months. One thousand nine hundred sixty-one implants reported survival rates of 99.2 (98.6-99.5) % at 1 year, 97.5 (95.9-98.4) % after 3 years, and 95.8 (93.3-97.4) % after 5 years; 1064 immediately loaded restorations presented survival rates of 98.9 (97.8-99.5) % after 1 year, 96.8 (93.6-98.4) % after 2 years, and 94.8 (89.6-97.4) % after 5 years. Comparing baseline to 12-month data using the Hedges' g effect size (95% CI), papilla height presented an overall effect size of -0.71 (-1.25, -0.1) mm, midfacial recession change of -0.15 (-0.66, 0.36) mm, and a 0.82 (0.37, 1.28) gain in PES.

CONCLUSIONS

Immediate implant placement and immediate loading can be considered a predictable and safe treatment option for single maxillary anterior restorations with adequate survival rates and favorable esthetics outcomes for up to 5 years.

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.

Clinical outcomes of retention of the buccal root section combined with immediate implant placement: A systematic review of longitudinal studies

INTRODUCTION

Immediate implant placement in conjunction with partial extraction therapy has been shown to result in functional osseo- and dento-integration with partial preservation of the periodontal ligament (PDL) in humans. Strategic buccal root retention for PDL preservation is a biologically driven procedure that maintains alveolar ridge dimensions and esthetics, while allowing for implant placement. The aim of this study was to conduct a systematic review of longitudinal clinical outcomes of PDL-mediated ridge preservation in conjunction with implant placement in adults, compared with conventional immediate implant placement with total extractions. The primary outcome for this study was marginal bone level (MBL) changes after strategic buccal root retention implant placement techniques.

MATERIALS AND METHODS

To address a predefined PICOS question, a systematic search of randomized clinical trials and cohort studies with at least 10 participants per group and a minimum 12-month follow-up was conducted. A two-phase systematic selection strategy, data extraction, and risk of bias assessment, was performed independently and in duplicate. Randomized trials were quantitatively analyzed in a meta-analysis.

RESULTS

Ten human studies fulfilled the predefined criteria and were included; three clinical trials and seven cohort studies, for a total of 506 patients and 587 implants. PDL-mediated implant placement of single-rooted periodontally healthy teeth was found to reduce marginal peri-implant bone loss and buccal plate changes as compared to conventional immediate implants across studies, while implant survival and success rates were comparable between the two procedures. A meta-analysis found that bone changes were significantly less when retention of the buccal root section was performed as compared to total extractions (standardized mean difference: [-4.53, -0.11]); the three clinical trials were, however, largely heterogeneous (I2 : 93.1%; Q = 28.98, p < 0.001).

CONCLUSION

Strategic retention of the buccal root section has a benefit in terms of dimensional ridge stability over conventional immediate implantation when implemented in carefully selected cases of single-rooted teeth.

Custom-made computer-aided-design/ computer-assisted-manufacturing (CAD/CAM) synthetic bone grafts for alveolar ridge augmentation: A retrospective clinical study with 3 years of follow-up

PURPOSE

To report on the results obtained with computer-aided-design/ computer-assisted-manufacturing (CAD/CAM) custom-made synthetic hydroxyapatite/beta-tricalcium-phosphate (HA/beta-TCP) bone grafts in alveolar ridge augmentation for dental implant placement.

METHODS

The procedure included: (1) cone-beam computed tomography (CBCT) of the bone defect; (2) virtual design of the custom-made onlay bone grafts; (3) milling of grafts from a pre-formed block of synthetic HA/beta-TCP; and (4) bone reconstructive surgery. Implants were placed 8 months later. The patients were followed for 3 years. The study outcomes were: (1) intra- and immediate post-operative complications; (2) 8-month vertical and horizontal bone gain; (3) implant survival; (4) implant-crown success; and (5) peri-implant marginal bone loss (MBL).

RESULTS

Twenty-six patients underwent ridge augmentation with custom-made CAD/CAM HA/beta-TCP onlay grafts. Eight months later, these patients were rehabilitated with dental implants. During surgery, 25/26 (96.1%) of the grafts adapted well to the bone defect. Immediate post-operative complications were pain and swelling (2/26 patients: 7.6%), and bone graft exposure (3/26: 11.5%); one exposure led to infection, removal of the graft, and failure of the procedure. Excellent integration of the other grafts was observed 8 months after the regenerative procedure, with mean vertical and horizontal bone gains of 2.10 mm (± 0.35) and 2.96 mm (± 0.45), respectively. Twenty-five implants were placed and restored with single crowns. Three years later, all implants were in function. The 3-year implant crown success rate and peri-implant MBL were 92.0% and 0.7 mm (±0.19), respectively.

CONCLUSIONS

With custom-made CAD/CAM synthetic HA/beta-TCP onlay grafts reconstruction of small vertical and/or horizontal defects of the alveolar ridge was obtained; this enabled implant placement, with high implant-crown success rate after 3 years. Further studies are needed to validate this technique.

STATEMENT OF CLINICAL RELEVANCE

Custom-made CAD/CAM synthetic HA/beta-TCP onlay grafts may represent an option for regeneration of small bone defects prior to implant placement.

Guided implant surgery with R2Gate®: A multicenter retrospective clinical study with 1 year of follow-up

PURPOSE

To present the results obtained with a novel sleeveless and keyless guided implant surgery system.

METHODS

Inclusion criteria for this multicenter clinical retrospective study were fully or partially edentulous patients who had been treated with a sleeveless and keyless guided implant surgery system (R2Gate®, Megagen), and who had been rehabilitated with fixed restorations, with a minimum follow-up of 1 year. All surgeries and prosthetic procedures were conducted following the same protocol, and data were obtained from the patients' medical records. The outcomes were the fit and stability of the surgical guide, any intra-operative and immediate post-operative complications, any biologic and prosthetic complications that occurred during the 1-year follow-up period, implant survival, and prosthetic success.

RESULTS

Sixty patients were selected for the installation of 124 implants, through a guided procedure: 66 sleeveless, keyless surgical guides were manufactured. The incidence of immediate intra-operative (lack of space: 12.1%; lack of implant stability 2.6%) and immediate post-operative (pain and discomfort: 6.6%; mild swelling 3.3%) complications was low. In total, 112/124 implants (90.3%) were successfully placed with a guided procedure, in 52 patients; among them, 82 (73.2%) were placed with a flapless procedure. Thirty fixtures supported single crowns (SCs), 42 fixed partial dentures (FPDs) and 52 full-arch (FA) restorations. Sixty-two fixed prosthetic restorations (30 SCs, 22 FPDs and 10 FAs) were delivered; among these restorations, 15 (24.1%) were subjected to immediate functional loading. All implants (100%) survived. Two implants had peri‑implant mucositis (1.6%), two SCs had abutment screw loosenings (1.6%), two FAs and one FPD had ceramic chipping/fracture (2.4%), for an overall prosthetic success amounting to 88.7%.

CONCLUSIONS

Within the limits of this study, this novel guided surgery system appeared to be clinically reliable; further studies are needed to confirm these results.

STATEMENT OF CLINICAL RELEVANCE

The use of sleveless and keyless surgical guides can be clinically reliable and may be represent a valid option for the surgeon.

Influence of Serum Vitamin D Levels on Survival Rate and Marginal Bone Loss in Dental Implants: A Systematic Review

This systematic literature review set out to investigate the relationship between serum vitamin D levels and dental implants in terms of survival rates, marginal bone loss, and associated complications. The review was conducted according to PRISMA guidelines, performing an electronic search in four databases (Pubmed, Web of Science, Cochrane, and Scopus), complemented by a manual search up to April 2022. Four articles were selected for analysis. The Newcastle-Ottawa Quality Assessment Scale tool was used to assess the quality of evidence of cohort studies, and the Cochrane bias assessment tool was used to assess the quality of evidence of randomized clinical trials. The study included 1089 patients restored with 1984 dental implants, with follow-up periods ranging from 20-240 months. Cases presenting lower serum vitamin D levels obtained slightly worse results in terms of marginal bone loss. Longer follow-up periods are needed in order to determine whether serum vitamin D levels affect implant survival rates and osseointegration over time.

The beyond the gap filling approach: Modeling facial and interproximal tissues and improving esthetics for anterior flapless immediate implant placement

OBJECTIVE

Maintenance of adequate interproximal tissue height between an implant and a natural tooth or between adjacent implants represents an esthetic challenge in implant dentistry. The aim of this case report is to describe a modified technique referred to as the beyond the gap filling (BGF) approach designed to improve the horizontal and vertical components of the facial aspect and particularly the height of interproximal bone peaks around immediately placed implants into fresh extraction sockets.

CLINICAL CONSIDERATIONS

Four patients (five teeth) requiring anterior tooth extraction were treated with the BGF approach that included: (a) minimally traumatic tooth extraction; (b) immediate implant placement without flap elevation; (c) installation of a narrow profile healing abutment to protect the implant during grafting; (d) grafting with a construct with 90% bovine bone granules and 10% porcine collagen packed coronally to the facial and interproximal bone walls above the level of the bone crest; and (e) delivery of an immediate restoration.

CONCLUSIONS

The current report suggests that the level/height of the interproximal bone crests between an implant and a natural tooth or between two adjacent implants can be improved by the BGF approach and, consequently, papilla height can be maintained in cases with a high risk of papilla height collapse and, consequently, esthetic outcomes can be maximized.

CLINICAL SIGNIFICANCE

The BGF is a simple technique to be used by clinicians to prevent significant papilla collapse in anterior immediate implants and consequently achieve maximum esthetic outcomes in implant dentistry.

Vitamin D Supplementation for Prevention of Dental Implant Failure: A Systematic Review

Background

Many factors play a significant role in osseointegration and healing after dental implant insertion and restoration. Some factors are related to dental biomaterials, such as the dental implant, prosthesis, and grafting materials. Other factors can be connected to operator skills and accumulated experience. Local and systemic patient-related factors are crucial in determining the success of the dental implant. Thorough examination and analysis of local factors using available examination tools are vital to prepare the implant candidate for such treatment. The patient's systemic condition directly affects the healing of the dental implant. One of the most overlooked systemic factors is the patients' vitamin D level, which influences bone formation around the implant and subsequent osseointegration. The current review examined the available literature regarding the association between vitamin D supplementation and dental implant osseointegration.

Methods

Data of this review were derived from recent research available on PubMed, Google Scholar, and Scopus. Inclusion criteria were the relation between the vitamin D serum and dental implant osseointegration or failure. The Systematic Reviews and Meta-Analyses (PRISMA) checklist was followed to perform the review. The study's outcome was the need for vitamin D supplementation to prevent implant failure.

Results

Five human studies (including case reports, case series, and retrospective studies) and six animal studies. All included studies discussed the relationship between vitamin D, early dental implant failure, and bone implant contact. Three retrospective studies found no significant relationship between vitamin D supplementation and EDIFs in humans. On the other hand, one retrospective study showed a significant relationship in humans. A case report and case series claimed that the implant was successfully placed after vitamin D supplementation. A total of four animal studies showed a significant relationship between vitamin D supplementation and osseointegration of the dental implant. Two animal studies showed no significant association.

Conclusion

To ensure optimal treatment outcomes, it is recommended to supplement the patient with vitamin D if the serum level is not within the normal range. Further clinical studies and case reports are needed to confirm the association between serum vitamin D levels and osseointegration.

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.

Esthetic Assessment Succeeding Anterior Atrophic Maxilla Augmentation with Cancellous Bone-Block Allograft and Late Restoration Loading

Background: Various conditions may lead to bony deficiency in the anterior maxilla. The present study evaluated esthetic (PES—pink esthetic score and WES—white esthetic score) results after augmentation of the anterior atrophic maxilla using cancellous bone-block allograft followed by implant placement and late (conventional) loading. Methods: Cohort study that included 33 patients with missing teeth in the upper anterior region characterized by extensive bone loss. Allogeneic cancellous bone-blocks were used for augmentation. Six months later, a dental implant was inserted. After a waiting time of an additional six-months, implant exposure and reconstruction were performed. The mean follow-up period was 62.93 ± 17.37 months (range 19–82 months). Results: The mean value of PES/WES was 17.8 ± 2.78. All patients had a PES/WES value above 12 (threshold value defined as clinically acceptable esthetics). The mean value of PES was 9.0 ± 1.79 and the mean value of WES was 8.8 ±1.84. Conclusions: Bone augmentation of the anterior atrophic maxilla using cancellous block-allograft and late loading supports achievement of a predictable esthetic result with long-term stability of soft and hard tissues around implant-supported reconstructions.

Esthetic Outcome and Oral Health-Related Quality of Life after Restoration with Single Anterior Maxillary Implants

Background/Aim: To evaluate the esthetic outcome of single implant restorations and the correlation of these esthetic results between patient satisfaction and oral health-related quality of life (OHRQoL).

Material and Methods: 15 patients with single-tooth implants in the anterior maxilla region were included in this study. Patients were clinically followed to evaluate the esthetic outcomes of implant prostheses and photographs of the implant site were obtained using a digital camera. A researcher evaluated the photographs according to the pink esthetic score/white esthetic score (PES/WES) index. Patients were asked to complete a questionnaire including 13 questions to evaluate their satisfaction with the overall implant and restoration treatments using by visual analogue scale (VAS). OHRQoL was evaluated by patients with the questionnaire Oral Health Impact Profile-14 (OHIP-14).

Results: The mean PES/WES was 13.6. In Ohip-14 questionnaire, the questions were answered ‘never’ generally. The mean VAS score was 9.01±0.9 and ranged from 7.6 to 9.7. There was no correlation between VAS and PES/WES (p= 0.484), similarly, there was no correlation between OHIP-14 and PES/WES (p= 0.763).

Conclusions: All of the implant restorations’ PES/WES scores were clinically acceptable. Professionals evaluated the esthetic outcome more suspicious than patients. Patients were satisfied with the esthetic results.

Clinical and esthetic outcomes of immediate implant placement compared to alveolar ridge preservation: a systematic review and meta-analysis

AIM

The aim of this systematic review was to evaluate the efficacy of immediate implant placement (IIP) compared to implants placed after alveolar ridge preservation (ARP) in terms of clinical, esthetic, and patient-reported outcomes.

METHODS

A manual and electronic search (National Library of Medicine) was performed for controlled clinical trials, with at least 12 months of follow-up. Primary outcome variable was implant survival and secondary outcomes were marginal bone level (MBL) (change), pink esthetic score (PES), mid-facial mucosal level (change), papilla index score, complications, and patient-reported outcomes.

RESULTS

A total of 10 publications were included (7 randomized clinical trials and 3 controlled clinical trials). The results from the meta-analyses showed that survival rate was significantly lower in the IIP group compared to ARP group [RR = 0.33; 95% CI (0.14; 0.78); p = 0.01]. No significant differences between the two groups were observed regarding radiographic MBL, PES scores, or mid-facial mucosal level (p > 0.05).

CONCLUSION

The results from this systematic review and meta-analysis showed that IIP had lower survival rates and similar esthetic results when compared to ARP.

CLINICAL RELEVANCE

Clinicians should weigh the benefits and disadvantages of each intervention to select the optimal timing of implant placement.

The Possible Role of Vitamin D Deficiency in Early Implant Failure

Background. Dental implants are one of the most successful treatments for restoring tooth function and beauty. Identifying the causes of dental implant failure is useful and vital. This review was aimed at studying the possible role of vitamin D in early implant failure. Method and Material. This review was designed based on the PRISMA guideline. Data was collected using keywords including implant, vitamin D, deficiency, failure, dental, OR tooth in international databases including PubMed, Scopus, Web of Science, Cochrane, and Embase, until 2020. Based on the inclusion and exclusion criteria, data were extracted and gathered in a checklist. Results. Finally, twelve studies were selected from five different countries. In 6 studies (2 animal studies and four human studies), there was no significant relationship between vitamin D deficiency and dental implant failure. In the other six studies (1 animal study and five human studies), there was a significant relationship in this regard. Conclusion. It is difficult to conclude the association between vitamin D and implant failure based on the literature’s researches. However, vitamin D appears to play an essential role in implant success through its effects on immune system modulation.

The Relationship Between Serum Level of Vitamin D3 and Osseointegration Around the Dental Implant

At present, dental implants are used more than before, and their high success rate is attributed to sufficient osseointegration, which depends on prosthetic-, implant-, and patient-related factors. The quality and quantity of bone and the host response are the main patient-related factors. Vitamin D3 affects bone metabolism by stimulating both osteoclasts and osteoblasts. This study aimed to review the human studies on the efficacy of vitamin D3 for dental implant osseointegration. Search of the literature yielded only 4 studies on human models, of which 2 showed the optimal efficacy of vitamin D3 for dental implant osseointegration, whereas the remaining 2 did not report any positive effect. However, this finding may be related to the small sample size of the vitamin D3-deficient group, which can compromise statistical analyses. In conclusion, vitamin D3 seems to be effective for dental implant osseointegration, although further research is required on human models.

Retaining and Regaining Esthetics in the Anterior Maxillary Region Using the Socket-Shield Technique

With the advancement in the implant in dentistry, improvement in the implant designs and placement protocol has enhanced the esthetics outcomes in the anterior zone. Yet the preservation of the peri-implant soft tissue and providing an appropriate emergence profile to the implant crown prosthesis, the tissue grafting procedures are necessary to overcome the ridge contour change. However through the socket-shield technique, the bone resorption process is preserved, and the contour of the buccal gingiva is maintained, thereby preventing its collapse and achieving good aesthetic results. This case report describes the placement of an implant in the upper anterior region and rehabilitation with a cement-retained crown prosthesis using the socket-shield technique and the patient being followed up for 6 months with good results.

Evaluation of the Treatment of Partially Edentulous Patients With Bone Level Tapered Implants: 24-Month Clinical and Radiographic Follow-Up

The aim of this case series was to assess, over a period of 24 months, the clinical and radiographic outcomes in partially edentulous patients receiving bone-level tapered implants. In total, 33 partially edentulous patients and 50 implants were evaluated. Patients received single or multiple implants in the posterior maxilla. Clinical and radiographic measurements of vertical bone levels were assessed at surgery, at loading, and 6, 12, and 24 months after surgery. The success and survival rates of the implants were also evaluated. Within the 24-month follow-up, only 1 implant failed (2.0%). Other biological or technical complications were not observed. The mean insertion torque was 34 ± 5.3 Ncm. Bone-level changes of 0.35 ± 0.23 mm were found between surgery and 12 months after surgery, and changes of 0.03 ± 0.05 mm were found between 12 months and 24 months after surgery. The overall change from surgery to 24 months after implant placement was 0.38 ± 0.24 mm. Most of the bone loss occurred between surgery and 3 months (0.28 ± 0.19 mm; P < .001); thereafter, the loss was minimal and statistically nonsignificant. Bone-level tapered implants yielded a high survival and success rate with minimal bone-level changes. Tapered implants could be considered as a predictable treatment option for partially edentulous patients with different types of bone qualities and loading protocols.

Aesthetics outcome of immediately restored single implants placed in extraction sockets in the anterior maxilla: A case series study

Background. Immediate single implant placement and restoration (IIR) is recognized as a novel method and is the main request of many patients. This study was designed to evaluate the aesthetic outcomes of immediately restored single implants placed in extraction sockets in theanterior maxilla.

Methods. In this case series study, 18 patients were selected from two private clinics after placing a single-tooth implant in the anterior maxilla. Immediate provisional crowns were delivered on the following day or at most 48 hours later, and guidelines were provided. The Pink Esthetic Score (PES) questionnaire was used at 6- and 12-month follow-ups to assess aesthetic outcomes. Data were analyzed with single t-test and dependent t-test.

Results. In general, the results showed that the status of the mesial papilla, distal papilla, curve of the facial soft tissue line, level of the facial peri-implant mucosa and root convexity soft tissue in IIR method were optimal (P<0.05), with total PES means of 9.44±0.783 and 8.58±1.003 after 6 and 12 months, respectively. Also, the results showed a significant difference in PES between the 6-month and 12-month intervals (P<0.05).

Conclusion. IIR is a viable method that resulted in optimal aesthetic outcomes based on PES in the short term. Considering its confirmation in this study and previous studies, it is recommended that dentists apply this method.

Influence of the implant-abutment connection on the ratio between height and thickness of tissues at the buccal zenith: a randomized controlled trial on 188 implants placed in 104 patients

Background

To compare tissue response to two implant systems, featuring internal hexed connections with different designs.

Methods

Patients enrolled in this randomized controlled trial were assigned to two groups. In Group 1, patients were treated with implants with a 5° conical internal hexed connection (Anyridge®, MegaGen, South Korea). In Group 2, patients were treated with implants with an internal hexed connection (Core®, Kristal, Italy). After implant placement and a provisionalisation period of 12 months, impressions were taken, stone casts were poured and digitised with a desktop scanner (D700®, 3Shape, Copenhagen, Denmark). In a digital environment, for each fixture, two values were collected at the buccal zenith: the height of the peri-implant mucosa (mucosal height; MH), calculated from the vestibular shoulder of the implant analogue to the upper gingival margin of the supra-implant tissue; and the width of the peri-implant mucosa (mucosal thickness; MT), calculated from the vestibular shoulder of the analogue to the external mucosa point perpendicular to the implant major axis. The mean and standard deviation for MH and MT, as well as their ratios, were calculated for each group; the sectors in which the implants were placed were also considered. Finally, correlation between MH, MT, connection type and sector was assessed by Pearson’s correlation coefficient, with significance level set at 0.05, and a confidence interval (CI) set at 95%.

Results

Data deriving from 188 implants placed in 104 patients were evaluated. The mean MH values were 3.32 (± 0.12) and 2.70 (± 0.16) mm for Groups 1 and 2, respectively. The mean MT values were 4.37 (± 0.16) and 3.93 (± 0.18) mm for Groups 1 and 2, respectively. Group 1 showed higher MH and MT values and a better ratio (1.50 ± 0.88) than Group 2 (1.81 ± 1.20). The MH, MT and MH/MT ratio were significantly influenced both by sector (p = 0.015) and group (p = 0.047).

Conclusions

Within the limits of this study, the 5° connection implants supported a more extended tissue height and thickness at the buccal zenith, and a better ratio between them.

Trial registration

This study was retrospectively registered in Clinicaltrials.gov, with number NCT04160689, dated 13/11/2019.

Complete-arch fixed reconstruction by means of guided surgery and immediate loading: a retrospective clinical study on 12 patients with 1 year of follow-up

Background

Guided implant surgery is considered as a safe and minimally invasive flapless procedure. However, flapless guided surgery, implant placement in post-extraction sockets and immediate loading of complete-arch fixed reconstructions without artificial gum are still not throughly evaluated. The aim of the present retrospective clinical study was to document the survival and success of complete-arch fixed reconstructions without artificial gum, obtained by means of guided surgery and immediate loading of implants placed also in fresh extraction sockets.

Methods

A total of 12 patients (5 males and 7 females, with a mean age of 50.0 ± 13.8) were enrolled in this study. Implant planning was performed with a guided surgery system (RealGuide®, 3Diemme, Como, Italy), from which 3D-printed surgical templates were fabricated. All implants (Esthetic Line-EL®, C-Tech, Bologna, Italy) were placed through the guides and immediately loaded by means of a temporary fixed full-arch restoration without any artificial gum; the outcome measures were implant stability at placement, implant survival, complications, prosthetic success, soft-tissue stability, and patient satisfaction.

Results

One hundred ten implants (65 of them post-extractive) were placed flapless through a guided surgery procedure and then immediately loaded by means of provisional fixed full arches. Successful implant stability at placement was achieved in all cases. After a provisionalization period of 6 months, 72 fixed prosthetic restorations were delivered. Only 2 implants failed to osseointegrate and had to be removed, in one patient, giving a 1-year implant survival rate of 98.2% (108/110 surviving implants); 8/12 prostheses did not undergo any failure or complication during the entire follow-up period. At the 1-year follow-up control, soft-tissue was stable in all patients and showed satesfactory aesthetic results.

Conclusions

Within the limits of this study, complete-arch fixed reconstruction by means of guided surgery and immediate loading of implants placed in fresh extraction sockets appears to be a reliable and successful procedure. Further long-term prospective studies on a larger sample of patients are needed to confirm these positive outcomes.

Dental Implant Outcomes in Grafted Sockets: a Systematic Review and Meta-Analysis

Objectives

To assess the treatment outcomes of the dental implants placed in the grafted sockets.

Material and Methods

A search protocol was developed to evaluate the treatment outcomes of dental implants placed in the grafted sockets in terms of implant survival rates (primary outcome), marginal-bone-level (MBL) changes, clinical parameters (i.e., bleeding on probing, probing depth), occurrence of peri-implant diseases, and aesthetic outcomes (secondary outcomes). Randomized controlled clinical trials (RCTs), controlled clinical trials, and prospective studies with at least 12 months of follow-up and a minimum of 10 patients having at least one dental implant inserted into the grafted socket were conducted. MEDLINE (PubMed) was searched for relevant articles published until 1st April 2019. A meta-analysis was performed using the random-effects model on the selected qualifying articles.

Results

The present analysis included 7 RCTs. The survival rate of the implants inserted into the grafted sockets ranged from 95 to 100% after 1 to 4 years of follow-up. MBL loss was found to be significantly greater for the implants placed in the non-grafted healed sites than for those placed in the previously grafted sockets (weighted mean difference = -1.961 mm, P < 0.0001). In terms of MBL changes, no difference was detected between immediately inserted implants versus implants placed in previously grafted sockets. None of the included studies reported on the clinical parameters or occurrence of peri-implant diseases

Conclusions

Implants inserted into the previously grafted sockets showed high survival rates and lower marginal-bone-level loss than the implants inserted into the non-grafted sites.

Ratio between Height and Thickness of the Buccal Tissues: A Pilot Study on 32 Single Implants

BACKGROUND

Previous studies have suggested that mucosal height is related to the bone level and soft tissue thickness. The purpose of this pilot study was to investigate the ratio between the height and width of the tissues around single implants with a conical connection and platform switching.

METHODS

All patients receiving single implants (Anyridge^®, MegaGen, Gyeongbuk, South Korea) and restored with single crowns, in a three-month period, were included in this study. After a provisionalization of 12 months, precision impressions were taken and stone casts were poured for measurements. For each implant, two values were collected at the buccal site: the mucosal height (MH), calculated from the vestibular shoulder of the implant to the upper gingival margin of the supra-implant tissue; and the mucosal thickness (MT), calculated from the vestibular shoulder of the analogue to the external mucosa point perpendicular to the implant major axis. Mean, standard deviation (SD), and confidence intervals (CI 95%) for MH and MT, as well as their ratios, were calculated. Correlation between MH and MT was assessed by Pearson's correlation coefficient, with significance level set at 0.05.

RESULTS

32 single Anyridge^® implants were eligible for this evaluation. The mean MH was 3.44 mm (±1.28), the mean MT was 3.29 (±1.46). The average of the ratio between MH and MT of the supra-implant mucosa was therefore 1:1.19 (±0.55). The relation between MH and MT was statistically significant at p ≤ 0.01 (Pearson two-tailed 95% CI).

CONCLUSIONS

Our study found a constant relationship between width and height of the peri-implant mucosa. However, our results are different from those of Nozawa et al., who found a ratio of 1:1.5 between height and thickness of the peri-implant tissues. This may be determined by the different sample and follow-up period, as well as by the implants used in our study.

A systematic review of the survival and complication rates of zirconia-ceramic and metal-ceramic single crowns

OBJECTIVES

The aim of the present systematic review was to analyze the survival and complication rates of zirconia-based and metal-ceramic implant-supported single crowns (SCs).

MATERIALS AND METHODS

An electronic MEDLINE search complemented by manual searching was conducted to identify randomized controlled clinical trials, prospective cohort and retrospective case series on implant-supported SCs with a mean follow-up time of at least 3 years. Patients had to have been clinically examined at the follow-up visit. Assessment of the identified studies and data extraction was performed independently by two reviewers. Failure and complication rates were analyzed using robust Poisson's regression models to obtain summary estimates of 5-year proportions.

RESULTS

The search provided 5,263 titles and 455 abstracts, full-text analysis was performed for 240 articles, resulting in 35 included studies on implant-supported crowns. Meta-analysis revealed an estimated 5-year survival rate of 98.3% (95% CI: 96.8-99.1) for metal-ceramic implant supported SCs (n = 4,363) compared to 97.6% (95% CI: 94.3-99.0) for zirconia implant supported SCs (n = 912). About 86.7% (95% CI: 80.7-91.0) of the metal-ceramic SCs (n = 1,300) experienced no biological/technical complications over the entire observation period. The corresponding rate for zirconia SCs (n = 76) was 83.8% (95% CI: 61.6-93.8). The biologic outcomes of the two types of crowns were similar; yet, zirconia SCs exhibited less aesthetic complications than metal-ceramics. The 5-year incidence of chipping of the veneering ceramic was similar between the material groups (2.9% metal-ceramic, 2.8% zirconia-ceramic). Significantly (p = 0.001), more zirconia-ceramic implant SCs failed due to material fractures (2.1% vs. 0.2% metal-ceramic implant SCs). No studies on newer types of monolithic zirconia SCs fulfilled the simple inclusion criteria of 3 years follow-up time and clinical examination of the present systematic review.

CONCLUSION

Zirconia-ceramic implant-supported SCs are a valid treatment alternative to metal-ceramic SCs, with similar incidence of biological complications and less aesthetic problems. The amount of ceramic chipping was similar between the material groups; yet, significantly more zirconia crowns failed due to material fractures.

The Root Membrane Technique: A Retrospective Clinical Study With Up to 10 Years of Follow-Up

PURPOSE

Immediate implant placement in conjunction with intentional root retention is a recently introduced technique, but the majority of existing documentation is limited to short-term reports with low level of evidence. Hence, the aim of this study was to document the long-term clinical and radiographic results of the root membrane technique.

METHODS

This retrospective study reports on clinical results of the root membrane technique for periodontal ligament-mediated immediate implant placement with up to 10 years of follow-up from 3 private dental practices. Anterior implants placed with immediate loading from January 2006 to December 2016 were assessed. Kaplan-Meier estimators were computed for reporting of implant success and survival.

RESULTS

A sample of 182 patients (82 men and 100 women, age range: 18-83 years) received 250 immediate implants (230 maxilla, 20 mandible) after the root membrane concept and followed-up for a mean of 49.94 months (±32.5). Overall, 5 implant failures were recorded for a 10-year cumulative patient-level implant survival rate of 96.5%. Considering mechanical and biological complications, the 10-year cumulative implant success rate was 87.9%.

CONCLUSIONS

Within the limits of the retrospective design, the root membrane technique showed long-term success rates comparable to those of conventional immediate implants.

Prosthetic Complications Affecting Single-Tooth Morse-Taper Connection Implants

PURPOSE

To evaluate the long-term cumulative implant survival rate (CISR%) and cumulative implant-crown success rate (CICSR%) of single-tooth Morse-taper connection implants, with particular attention to documenting the incidence of prosthetic complications.

METHODS

The customized records of all patients who had been treated with single-tooth Morse-taper connection implants in 2 dental centers during the period between January 2002 and December 2012 were revisited. These records included patient-related (gender, age at surgery, smoking, bruxism), implant-related (date of insertion, site/location, and length/diameter of the implant, previous/concomitant bone regeneration), and restoration-related (date of delivery of the provisional and final crown) information. In addition, these records contained information about any implant failure and biologic and/or prosthetic complication that occurred during the follow-up period as well as the radiographic documentation. The follow-up period comprised between 5 and 15 years. The main outcomes were CISR% and CICSR%, with the latter being defined as the condition in which no complication had affected the surviving implant-supported crown during the entire follow-up. Life-table analysis was used for the analysis of CISR% and CICSR%. Peri-implant marginal bone resorption (PIMBR) at 5, 10, and 15 years was a secondary outcome of this study.

RESULTS

In total, 578 patients who had received 612 implants were included in this study. The overall CISR% at 15 years was 94.8% (94.2% maxilla, 95.3% mandible). Among the surviving crowns, the overall CICSR% at 15 years was 94.5% (93.1% and 94.9% for anterior and posterior crowns, respectively), and the incidence of prosthetic complications was low (1.5%). The PIMBL amounted to 0.38 ± 0.29 mm, 0.49 ± 0.35 mm, and 0.94 ± 0.58 mm at the 5-, 10-, and 15-year follow-ups, respectively.

CONCLUSION

Morse-taper connection implants represent a reliable treatment procedure for the restoration of single-tooth gaps in the long term, with high CISR% (94.8%) at 15 years, a very low incidence of complications, and a high CICSR% (94.5%).

The Modified Socket Shield Technique

OBJECTIVE

In the anterior regions, the resorption of the buccal bone after tooth extraction leads to a contraction of the overlying soft tissues, resulting in an esthetic problem, particularly with immediate implant placement. In the socket shield technique, the buccal root section of the tooth is maintained, to preserve the buccal bone for immediate implant placement. The aim of this prospective study was to investigate the survival, stability, and complication rates of implants placed using a "modified" socket shield technique.

METHODS

Over a 2-year period, all patients referred to a dental clinic for treatment with oral implants were considered for inclusion in this study. Inclusion criteria were healthy adult patients who presented nonrestorable single teeth with intact buccal periodontal tissues in the anterior regions of both jaws. Exclusion criteria were teeth with present/past periodontal disease, vertical root fractures on the buccal aspect, horizontal fractures below bone level, and external/internal resorptions. The buccal portion of the root was retained to prevent the resorption of the buccal bone; the shield was 1.5 mm thick with the most coronal portion at the bone crest level. All patients then underwent immediate implants. In the patient with a gap between the implant and shield, no graft material was placed. All implants were immediately restored with single crowns and followed for 1 year. The main outcomes were implant survival, stability, and complications.

RESULTS

Thirty patients (15 males, 15 females; mean age was 48.2 ± 15.0 years) were enrolled in the study and installed with 40 immediate implants. After 1 year, all implants were functioning, for a survival rate of 100%; excellent implant stability was reported (mean implant stability quotient at placement: 72.9 ± 5.9; after 1 year: 74.6 ± 2.7). No biologic complications were reported, and the incidence of prosthetic complications was low (2.5%).

CONCLUSIONS

The "modified" socket shield technique seems to be a successful procedure when combined with immediate implant placement, because the root fragment does not interfere with osseointegration and may be beneficial for the esthetics, protecting the buccal bone from resorption.

Full in-Office Guided Surgery with Open Selective Tooth-Supported Templates: A Prospective Clinical Study on 20 Patients

Background: Guided implant surgery appears to have several benefits, such as the possibility of inserting flapless implants in a prosthetically driven manner, avoiding dangerous anatomical structures. However, to date, only a few surgeons routinely use guided surgery in partially edentulous patients. Aim: To present the results obtained with tooth-supported surgical templates characterized by an innovative open design with selective support, and manufactured via a full in-office procedure with a low-cost desktop 3D printer. Methods: Over a two-year period (2016–2018), all partially edentulous patients with one to three missing teeth (in maxilla and/or mandible), referred to a private dental practice for restoration with dental implants, were considered for inclusion in this prospective clinical study. An intraoral scanner (CS 3600^®, Carestream Dental) and cone beam computed tomography (CS 9300^®, Carestream Dental) were used to acquire the 3D information on the patients. Guided surgery software (SMOP^®, Swissmeda) was used to plan the surgeries and to design open, selective, tooth-supported templates that were fabricated with a stereolithographic (SLA) desktop 3D printer (XFAB2000^®, DWS). Guided implant surgeries were performed and patients were followed for a period of one year. The study outcomes were fit and stability of surgical templates, duration (time) of surgery, intra and post-operative complications, and implant stability and survival. Results: Twenty (20) partially edentulous patients (9 males, 11 females; mean age 54.4 ± 9.4 years) were included in the study; 28 open, selective, tooth-supported templates were designed with the aim of inserting 38 implants. Among the surgical templates, 24 had optimal fit and stability, three had optimal fit and sufficient stability, and only one had inadequate fit and unsatisfactory stability and was therefore not suitable for clinical use. The average time of the intervention was 15.7 ± 5.2 min per template. No intra-operative complications were reported, but one implant was not stable at placement and had to be removed. In total, 36 implants were restored with 10 two-unit fixed partial prostheses and 16 single crowns. All implants were successfully functioning at one year, even if, in two single crowns, minor prosthetic complications (abutment screw loosening) occurred. Conclusions: Full in-office guided surgery with open, selective, tooth-supported templates seem to represent a clinically predictable surgical procedure to restore partially edentulous patients. Further studies are needed to confirm these positive outcomes.

Low serum vitamin D and early dental implant failure: Is there a connection? A retrospective clinical study on 1740 implants placed in 885 patients

Background. Since osseointegration depends on bone metabolism, low levels of vitamin D in the blood may negatively affect bone formation around dental implants. To date, only a few studies have investigated the possible connection between serum levels of vitamin D and early dental implant failure (EDIF), i.e. failure that occurs within 4 months after placement, before the connection of the prosthetic abutment. The aim of this study was to investigate whether there is a relationship between low serum levels of vitamin D and EDIF.

Methods. Data used for this retrospective study were derived from the records of a private dental clinic. Inclusion criteria were patients who had been treated with dental implants, inserted with a submerged technique from January 2003 to December 2017. EDIF was the outcome of this study. Chi-squared test was used to investigate the effect of patient-related variables (age, gender, smoking habit, history of periodontal disease and serum levels of vitamin D) on EDIF.

Results. Originally, 885 patients treated with 1,740 fixtures were enrolled in this study. Overall, 35 EDIFs (3.9%) were reported. No correlation was found between EDIF and the patients' gender (P=0.998), age (P=0.832), smoking habit (P=0.473) or history of periodontal disease (P=0.386). Three EDIFs (11.1%) were reported in 27 patients with serum levels of vitamin D <10 ng/mL, 20 EDIFs (4.4%) in 448 patients with levels between 10 and 30 ng/mL, and 12 EDIFs (2.9%) in 410 patients with levels >30 ng/mL. Although there was a clear trend toward an increased incidence of EDIF with lowering of serum vitamin D levels, no statistically significant difference (P=0.105) was found among these three groups.

Conclusion. Within its limitations (retrospective design, low number of patients with severe blood levels of vitamin D enrolled), this study failed to demonstrate a significant relationship between low serum levels of vitamin D and increased risk of EDIF. However, since a dramatic increase in EDIFs with lowering of vitamin D levels in the blood has been reported, further clinical studies with appropriate design (prospective or randomized controlled studies on a larger sample of severely deficient patients) are needed to better investigate this topic

Immunohistochemical Evaluation of Peri-Implant Soft Tissues around Machined and Direct Metal Laser Sintered (DMLS) Healing Abutments in Humans

Background: Direct metal laser Sintering (DMLS) is an additive manufacturing technique that allows fabrication of dental implants and related components with a highly porous surface. To date, no human studies have investigated the soft tissue adhesion and presence of inflammatory infiltrate with porous DMLS healing abutments (HAs), nor have they compared these with the classic machined ones. Purpose: To evaluate the degree of cell adhesion (integrin expression) and the quantity/quality of inflammatory infiltrate, on HAs with different surfaces; full DMLS, full machined, and hybrid (half DMLS and half machined). Methods: Fifty implant patients were randomly assigned to receive one of these different Has: T1, full DMLS (11 subjects); T2, machined in the upper portion and DMLS in the lower one (10 subjects); T3, DMLS in the upper portion and machined in the lower one (19 subjects); T4, full machined (10 patients). Thirty days after placement, circular sections of soft tissues around HAs were retrieved for immunohistochemical evaluation. Results: With regard to the adhesion molecules, the samples showed different intensity of integrin expression, with a statistically significant difference (p < 0.001) between T1 and the other groups. All the samples were positive for the different clusters related to the inflammatory infiltrate (T lymphocytes, CD3; B lymphocytes, CD20; and macrophages, CD68), but a lower infiltrate was found in T1, with statistically significant differences (p < 0.001) among the groups. Conclusions: The HA surface seems to influence the degree of cell adhesion and the inflammatory infiltrate of the surrounding soft tissues.

Esthetic evaluation of natural teeth in anterior maxilla using the pink and white esthetic scores

BACKGROUND

Natural teeth in the anterior maxilla are critical in determination the esthetic outcome of single implant prosthesis.

PURPOSE

The present study aimed to explore aesthetics of natural teeth in the anterior maxilla using the Pink Esthetic Score/White Esthetic Score (PES/WES) index. Additionally, inherent weak spots of natural teeth and high-risk parameters of prostheses were also considered.

MATERIAL AND METHODS

This cross-sectional study was performed by photographic analysis.

RESULTS

A total of 102 subjects and 306 teeth (the right incisor, lateral incisor and canine) were included. The grand means of the PES and WES were 12.92 and 8.75, respectively. The score of soft tissue margin, soft tissue contour and outline/volume of the crown were significantly lower than other variables. The PES and WES showed a downward trend with age. Most of the PES/WES values of the females exceeded those of the males.

CONCLUSION

The average level of natural teeth in PES and WES assessment were around 13 and 9, respectively. The soft tissue margin, soft tissue contour and outline/volume of the crown were high-risk parameters for the esthetic outcomes of implant reconstructions. Underlying factors, such as age and gender, contributed to the esthetics of natural teeth change.

Removal of Implant and New Rehabilitation for Better Esthetics

Tooth loss can result in loss of facial esthetics, in addition to its effect on mastication, swallowing, and speech. Adequate planning is required in order for the prosthetic treatment of the teeth and implants to be successful. Here, we present a clinical case demonstrating that improper positioning of an implant can make prosthetic rehabilitation unfeasible, necessitating new surgical and rehabilitation planning to achieve the desired esthetics. The patient had a missing right lateral incisor and cuspid, and a buccally directed implant. The preferred treatment regimen involved the removal of this implant and placement of another one more properly positioned distally and three dimensionally. The repositioning of the implant made rehabilitation treatment with a mesial cantilever possible. Due to esthetic considerations, gingival conditioning in the cantilever region was performed in the temporary prosthesis phase. The changes adopted in planning the surgery and rehabilitation resulted in good esthetics as well as functional outcomes.

Evaluation of the influence of implant placement timing on the esthetic outcomes of single tooth implant treatment in the anterior maxilla: A retrospective study

OBJECTIVES

The purpose of this retrospective study was to investigate the influence of implant placement timing on the esthetic outcomes for single implants in the anterior maxilla.

MATERIALS AND METHODS

One hundred and ten patients (48 males; 62 females) who received a single-tooth implant after extraction either immediately (Type 1); after 4-8 weeks (Type 2); after 8-16 weeks (Type 3); or more than 16 weeks (Type 4) were evaluated in terms of esthetic outcomes after a mean post-placement interval of 26.3 months (range 12-116). Esthetic outcomes were measured using the Pink and White Esthetic Score (PES; WES). Stepwise regression analysis was performed to analyze the effect of timing of placement, as well as patient demographics and other clinical parameters on the esthetic outcomes.

RESULTS

No statistically significantly differences in PES were found between the various treatment modalities with Type 1 implants (n = 33) scoring 10.58 ± 1.65 (median: 11), followed by 10.36 ± 2.09 (median: 10.5), 9.68 ± 2.43 (median: 10), and 9.63 ± 2.21 (median: 10) for Type 2 (n = 14), Type 3 (n = 19), and Type 4 (n = 44), respectively. For immediate implants, a trend towards better esthetic outcomes was observed when implant placement was done flaplessly in cases with intact buccal bone (Type 1A, median PES 11) as compared to cases with partial/complete missing buccal plates where a flap was raised (Type 1B, median PES 10). Overall, the only parameter that influenced esthetic outcomes (as measured by PES) was gender, with females having significantly superior results. The median WES was 8 and 96% of the crowns were deemed esthetically acceptable, with crowns placed by specialist prosthodontists yielding higher scores than those placed by general practitioners.

CONCLUSIONS

Single tooth implants in the anterior maxilla showed satisfactory outcomes when measured with objective esthetic criteria. Timing of implant placement did not significantly influence the esthetic outcomes, although a trend towards better outcomes was seen with immediate implant placement as observed by higher median PES values.

CLINICAL SIGNIFICANCE

Single tooth implant placement in the anterior maxilla is a predictable treatment modality for achieving acceptable esthetic outcomes regardless of the timing of placement.

Immediate functional loading of single implants: a multicenter study with 4 years of follow-up

Background. In the current scientific literature there are only few studies on the immediate functional loading of single implants. The aim of the present present study was to evaluate the 4-year survival rate, complication rate and peri-implant marginal bone loss (PIMBL) of immediately loaded single implants inserted in healed ridges and fresh post-extraction sites.

Methods. Six centers were involved in this prospective study. The surgical and prosthetic protocol was defined in detail, before the start of recruiting patients. Recruitment of patients and performance of surgeries took place between February 2012 and February 2013. Criteria for inclusion were single-tooth gaps in healed ridges and fresh post-extraction sockets. All the fixtures (Anyridge®, Megagen Corporation, Gyeongbuk, South Korea) were functionally loaded immediately after insertion and followed for a period of 4 years. Outcome measures were implant survival, complications and PIMBL.

Results. Forty-six patients (18‒73 years of age) were selected. In total, 57 fixtures were placed (10 in fresh post-extraction sockets). After 4 years of functional loading, only one fixture was lost; therefore, high survival rates (97.6% patient-based; 98.1% implant-based) were reported. In addition, a limited incidence of biologic (4.8% patient-based; 3.8% implant-based) and prosthetic (9.7% patient-based; 7.6% implant-based) complications was reported. The overall 4-year PIMBL amounted to 0.38±0.21 mm (healed ridges: 0.4±0.21 mm; fresh post-extraction sockets: 0.33±0.20 mm).

Conclusion. Loading single implants immediately seems to be a highly successful treatment modality. However, long-term data are needed to confirm these positive outcomes.

Radial plane tooth position and bone wall dimensions in the anterior maxilla: A CBCT classification for immediate implant placement

STATEMENT OF PROBLEM

The biological and esthetic challenge of the post-extraction ridge is relevant to restorative implant dentistry, most significantly in the anterior esthetic zone. Previous authors have discussed facial bone wall dimensions and classified their variations. A reclassification may be pertinent.

PURPOSE

The purpose of this observational, clinical study was to introduce a new classification system for anterior maxilla tooth position with guidelines for immediate implant placement. Data for facial and palatal bone wall height and thickness are also presented.

MATERIAL AND METHODS

Maxillary anterior teeth (n=591) were analyzed as viewed in the radial plane of cone beam computed tomography (CBCT) scans from 150 patients. Each tooth was classified according to its position and inclination within its alveolus (class I, middle of the alveolus; IA, thick facial bone; IB, thin facial bone; class II, retroclined; IIA, thick crestal bone; IIB, thin crestal bone; class III, proclined; class IV, facially outside bone envelope; class V, both thin facial and palatal bone with apical isthmus). Bone thickness was measured for both facial and palatal walls at the following points: crestal (A), mid-root (B), apex (C), and 4 mm beyond the apex. Bone wall height was also evaluated.

RESULTS

A thin facial bone wall predominated (≤1 mm) at the crest (83%) and the mid-root point (92%). Most palatal walls were thin (<1 mm) at the crest (63%) and thick (≥2 mm) at the mid-root point (98%) and apex (99%). Class I tooth position accounted for 6.1%, class II for 76.5%, class III for 9.5%, class IV for 7.3%, and class V for 0.7%.

CONCLUSIONS

Maxillary anterior teeth have predominantly thin facial bones, making palatal bone thickness a crucial variable. The new classification system for radial plane tooth position is a pragmatic clinical analysis for immediate implant treatment planning.

The Root Membrane Technique: Human Histologic Evidence after Five Years of Function

Background

The "root membrane" (RM) is a technique that has become popular among implantologists for placement of immediate implants in the anterior maxilla.

Purpose

To present histologic evidence of an immediate implant placed in the human anterior maxilla, according to the RM technique, and retrieved after five years.

Methods

A fixture, along with the surrounding tissues, was retrieved from the anterior maxilla of a 68-year-old patient, who had been treated five years earlier with immediate implant placement and RM technique. The specimen was processed for histologic/histomorphometric evaluation.

Results

The buccal bone plate was maintained without any resorption; a healthy periodontal ligament was evidenced. The implant showed osseointegration, with a high percentage of bone-to-implant contact (BIC = 76.2%). With regard to the space between the RM and the implant, the apical and medial thirds were filled with compact, mature bone; the coronal third was colonized by noninfiltrated connective tissue.

Conclusions

The RM technique appears to be effective in preventing bone resorption of the buccal bone plate of the human anterior maxilla, five years after the placement of an immediate implant.

Tapered, Double-Lead Threads Single Implants Placed in Fresh Extraction Sockets and Healed Sites of the Posterior Jaws: A Multicenter Randomized Controlled Trial with 1 to 3 Years of Follow-Up

PURPOSE

To evaluate the survival, success, and complication rates of tapered double-lead threads single implants, placed in fresh extraction sockets and healed sites of the posterior jaws.

METHODS

The enrolled patients were randomly divided into 2 groups: in the test group (TG), all implants were inserted at the time of tooth extraction; in the control group (CG), all implants were placed 3 months after extraction. The implants were followed for a period of 1 to 3 years after loading. The main outcomes were implant survival, complications, and implant-crown success.

RESULTS

Ninety-two patients had 97 installed implants (49 in the TG, 48 in the CG). Only two implants failed, in the TG; the survival rates were therefore 95.9% (47/49) and 100% (48/48) for TG and CG, respectively. In the surviving implants, no complications were reported, for an implant-crown success of 100%.

CONCLUSIONS

Although a significant difference was found in the levels of primary stability between TG and CG, single implants placed in fresh extraction sockets and healed sites of the posterior jaws had similar survival and complication rates. Crestal bone levels and peri-implant bone resorption showed similar values. A longer follow-up period is however required, to confirm these positive outcomes.

Histological Evidence of the Osseointegration of Fractured Direct Metal Laser Sintering Implants Retrieved after 5 Years of Function

Background

Direct metal laser sintering (DMLS) is an additive manufacturing technique that allows the fabrication of dental implants layer by layer through the laser fusion of titanium microparticles. The surface of DMLS implants is characterized by a high open porosity with interconnected pores of different sizes; therefore, it has the potential to enhance and accelerate bone healing. To date, however, there are no histologic/histomorphometric studies in the literature evaluating the interface between bone and DMLS implants in the long-term.

Purpose

To evaluate the interface between bone and DMLS implants retrieved after 5 years of functional loading.

Methods

Two fractured DMLS implants were retrieved from the human jaws, using a 5 mm trephine bur. Both the implants were clinically stable and functioned regularly before fracture. The specimens were processed for histologic/histomorphometric evaluation; the bone-to-implant contact (BIC%) was calculated.

Results

Compact, mature lamellar bone was found over most of the DMLS implants in close contact with the implant surface; the histomorphometric evaluation showed a mean BIC% of 66.1% (±4.5%).

Conclusions

The present histologic/histomorphometric study showed that DMLS implants were well integrated in bone, after 5 years of loading, with the peri-implant bone undergoing continuous remodeling at the interface.

The Ball Welding Bar: A New Solution for the Immediate Loading of Screw-Retained, Mandibular Fixed Full Arch Prostheses

Purpose

To present a new intraoral welding technique, which can be used to manufacture screw-retained, mandibular fixed full-arch prostheses.

Methods

Over a 4-year period, all patients with complete mandibular edentulism or irreparably compromised mandibular dentition, who will restore the masticatory function with a fixed mandibular prosthesis, were considered for inclusion in this study. The “Ball Welding Bar” (BWB) technique is characterised by smooth prosthetic cylinders, interconnected by means of titanium bars which are adjustable in terms of distance from ball terminals and are inserted in the rotating rings of the cylinders. All the components are welded and self-posing.

Results

Forty-two patients (18 males; 24 females; mean age 64.2 ± 6.7 years) were enrolled and 210 fixtures were inserted to support 42 mandibular screw-retained, fixed full-arch prostheses. After two years of loading, 2 fixtures were lost, for an implant survival rate of 97.7%. Five implants suffered from peri-implant mucositis and 3 implants for peri-implantitis. Three of the prostheses (3/42) required repair for fracture (7.1%): the prosthetic success was 92.9%.

Conclusions

The BWB technique seems to represent a reliable technique for the fabrication of screw-retained mandibular fixed full-arch prostheses. This study was registered in the ISRCTN register with number ISRCTN71229338.

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).

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.