Randomized controlled multicentre study comparing short dental implants (6 mm) versus longer dental implants (11–15 mm) in combination with sinus floor elevation procedures: 5‐Year data

Short (≤6 mm) compared with ≥10-mm dental implants in different clinical scenarios: A systematic review of randomized clinical trials with meta-analysis, trial sequential analysis and quality of evidence grading

AIM

To systematically identify, synthesize and critically summarize the available scientific evidence from randomized controlled trials (RCTs) regarding whether short (≤6 mm) perform as well as long (≥10 mm) implants regarding implant survival, marginal bone loss, and biologic and prosthetic complications in different clinical scenarios.

MATERIALS AND METHODS

Cochrane Collaboration's risk of bias tool and the GRADE approach were applied. Results were synthesized using random-effects meta-analyses assessed by trial sequential analyses.

RESULTS

Forty reports on 19 RCTs comprising 2214 (1097 short; 1117 long) implants were included. Moderate/high certainty/quality evidence demonstrated similar 5-year survival rates for ≤6-mm and ≥10-mm implants in non-augmented bone and full-mouth rehabilitation in either jaw, and for 6-mm implants in the maxilla instead of sinus lift. Nevertheless, the evidence for 5-year survival rates remains inconclusive or insufficient for the remaining combinations of implant lengths and clinical scenarios. They include 4-mm and 5-mm implants as alternatives to sinus lift as well as placing all implant lengths ≤6 mm instead of vertical ridge augmentation with long implants. Marginal bone level and short- and long-term biologic or prosthetic complications were similar.

CONCLUSIONS

Based on moderate/high certainty/quality evidence from 5-year RCTs, implants ≤6 mm may be viable alternatives to ≥10-mm implants in either jaw in native bone and full-arch rehabilitation, and 6-mm implants may be used as an alternative to sinus lift.

TRIAL REGISTRATION

PROSPERO ID: CRD42021254365.

Survival Rates of Short Dental Implants (≤6 mm) Used as an Alternative to Longer (>6 mm) Implants for the Rehabilitation of Posterior Partial Edentulism: A Systematic Review of RCTs

Short dental implants have been proposed as an alternative treatment option to bone regeneration procedures for the rehabilitation of resorbed alveolar ridges. The aim of this paper was to systematically review randomized controlled trials (RCTs) comparing short implants (≤6 mm) and longer implants (>6 mm) in atrophic alveolar ridges in terms of implant survival rates, peri-implant marginal bone loss (MBL), prevalence of peri-implantitis and technical complications. A thorough electronic search was performed until September 2023. RCTs with follow-up of at least 1-year post-loading comparing short implants with rough surfaces to longer implants in the posterior jaws of systemically and periodontally healthy, partially edentulous adults were considered. Studies with incomplete information on the number of patients, follow-up or definition of "short implants" were excluded. The revised Cochrane risk-of-bias tool for randomized trials was used for Risk of bias assessment. Fixed-effects meta-analysis of the selected studies was applied to compare the outcome variables. Random-effect meta-analysis was performed, on the basis of within-study comparisons. In total, 16 articles were selected for meta-analysis and incorporated 408 short implants and 475 longer implants inserted in 317 and 388 patients, respectively. The survival rates of longer implants in pristine or augmented bone were significantly increased compared to short implants (95%CI: 2-5%, p < 0.001). Standard-length implants displayed increased, although non-statistically significant MBL (95%CI: -0.17-0.04, p > 0.05), and prevalence of peri-implantitis (95%CI: 0-5%, p > 0.05). No statistically significant differences were observed between short and long implants in terms of technical complications (implant-level 95%CI: -4-6%, p > 0.05). Short implants represent a promising alternative treatment option for the rehabilitation of posterior jaws to avoid additional bone augmentation procedures. Nonetheless, they should be selected cautiously due to a potentially limited survival rate compared to longer implants. A major limitation of this study is the variability in the included studies regarding sample size, patient profile, type of bone, loading protocol, definition of peri-implantitis, among others. This study received no external funding. The study protocol was registered in PROSPERO (CRD42023485514).

Randomized controlled multi-centre study comparing shorter dental implants (6 mm) to longer dental implants (11-15 mm) in combination with sinus floor elevation procedures: 10-year data

AIM

To compare implant survival and complication rates between shorter and standard-length implants with sinus augmentation and restored with single crowns, at 10 years of loading.

MATERIALS AND METHODS

One-hundred and one patients (137 implants) with a ridge height of 5-7 mm in the posterior maxilla were randomly assigned to two treatment modalities: shorter implants (6 mm) (group short [GS]) or standard-length implants (11-15 mm) with sinus grafting (group graft [GG]). Following the insertion of final restorations, patients were regularly recalled for up to 10 years. Assessed outcomes encompassed implant survival, marginal bone levels (MBLs), biological and technical parameters and patient-reported outcome measures (OHIP-49 = Oral Health Impact Profile). Non-parametric statistical analysis was used to analyse the data.

RESULTS

For the 5- to 10-year follow-up period, 77 patients with 105 implants (GS: 36 patients/48 implants; GG: 41/57) were available for re-examination (drop-out rate 21%). Implant survival rates at the patient level were 96.0% (GS; 2 failures) and 100% (GG) (inter-group p = .24). Median MBLs amounted to 0.00 mm (min 0.00; max 3.25; GS) and 0.00 mm (min 0.00; max 4.55; GG) (inter-group p = .73). Technical complications predominantly occurred within the first 5 years (inter-group p > .05). Peri-implantitis rates were 4.2% (GS) and 13.3% (GG) (intergroup p = .37). Median OHIP-49 scores were 7.00 (0.00; 39.00; GS) and 9.00 (0.00; 196; GG) (inter-group p = .61) at 10 years.

CONCLUSIONS

Based on similar 10-year implant survival rates, reduced patient morbidity and lower costs, the use of shorter dental implants might well serve as an alternative treatment concept to longer implants placed in conjunction with sinus grafting for patients with a limited ridge height in the posterior maxilla. Study register: https://clinicaltrials.gov/ct2/show/NCT01030523.

Oral health-related quality of life (OHRQoL) and implant therapy: A prospective multicenter study of preoperative, intermediate, and posttreatment assessment

The purpose of this multicenter continuation study was to use high patient numbers in order to generate reliable statements regarding the association between different implant indications and OHRQoL. Patients with various types of indication for dental implants, ranging from single tooth loss to edentulous jaws, were included. Quality of life relating to dental implants was assessed through the oral health impact profile (OHIP-G-21), which has a summary score from 0 to 20 in healthy patients. In total, 16 253 patients from 29 centers (European Centers for Dental Implantology (ECDI)) were involved in the study between 2009 and 2021.8251 patients (50.7%) completed the questionnaire after implant insertion, and 4996 patients (30.7%) after prosthodontic treatment. The average age was 54 years (range 18-88 years). Posterior single-tooth gap (28.5%) and free-end gap (27.8%) were the most frequent indications. The preoperative OHIP-G-21 score for all patients was 32.81 (SD 11.92), while the score during the healing period was 30.00 (SD 10.72), and after completion of treatment 27.24 (SD 9.26) (p < 0.001). The most significant improvements in OHIP-G-21 scores were in the indication of edentulous jaw (phase 1, 41.81 (SD 15.53); phase 2, 35.39 (SD 14.22); phase 3, 29.60 (SD 10.12) (p < 0.001). The study revealed significant improvements in the most frequently reported problems (chewing, serious concerns, appearance) (p < 0.001). Insertion of dental implants and prosthodontic rehabilitation led to an improved OHRQoL for patients with all indications for dental implants. Special attention should be paid to patients with edentulous jaw, since in comparison with other indications it had the greatest impact on improving OHRQoL. The psychological dissatisfaction scale of the OHIP-G-21 represented the most important factors for patients, and these scores were substantially influenced by implant therapy. Thus, treating physicians should increase their focus on these factors, in order to avoid dissatisfaction and increase the likelihood of complete implant therapy success.

Evaluation of two treatment concepts of four implants supporting fixed prosthesis in an atrophic maxilla: finite element analysis

BACKGROUND

Currently, oblique placement of long implants or the use of short implants to circumvent the maxillary sinus area and provide support for fixed prostheses are viable alternatives. The purpose of this study was to compare these two treatment concepts and ascertain which one exhibits superior biomechanical characteristics.

METHODS

Two different treatment concept models were constructed. The first one, LT4I, consisting of two mesial vertical implants positioned in lateral incisor regions and two distal tilted implants (45°) situated in second premolar regions of the maxilla. The second model, VS4I, includes two mesial vertical implants in lateral incisor regions and two vertically positioned short implants in second premolar regions. Numerical simulations were conducted under three loading types: firstly, oblique forces upon the molars; secondly, vertical forces upon the molars; thirdly, oblique forces upon the incisors. The maximum principal stress (σmax) and minimum principal stress (σmin) of the bone, as well as von Mises stress of the implants, were calcuated.

RESULTS

Under oblique loading on the molar, higher stress values in the bone were observed in LT4I group. Under vertical loading on molar, higher stress values in the bone were also observed in LT4I group. Furthermore, little difference was found between the two groups under oblique loading on the incisor.

CONCLUSION

Both treatment concepts can be applicable for edentulous individuals with moderate atrophic maxilla. Compared to tilted implants, short implants can transmit less occlusal force to the supporting tissues.

Comparing short implants to standard dental implants: a systematic review and meta-analysis of randomized controlled trials with extended follow-up

PURPOSE

To compare the difference of marginal level changes (MBL), implant failure (IF), biological and prosthetic complications (BC and PC), and prosthetic failure (PF) of short implants (SH) and standard implants (ST).

MATERIALS AND METHODS

Electronic searches (PubMed, Web of Science, EMBASE, Scopus, Cochrane Central Register of Controlled Trials, and ClinicalTrials.gov) and manual searches were performed to identify all randomized controlled trials (RCTs) evaluating SH to ST. Applying Stata, a meta-analysis was conducted on the weighted mean difference (WMD) and standardized mean difference (SMD) of MBL and the risk difference (RD) of the secondary outcome.

RESULTS

Twenty-four articles were involved in the present study. There were statistically significant differences in MBLs, preferring short implants in the maxilla (WMD: -0.147 (CI: -0.224, -0.070), I2: 76.6%; SMD: -0.757 (CI: -1.226, -0.289), I2: 89.2%) and in the mandible (WMD: -0.377 (CI: -0.656, -0.098), I2: 85.8%; SMD: -0.811 (CI: -1.418, -0.204), I2: 78.8%). There were no significant differences in IF (RD: 0.011 (-0.002, 0.023), I2: 0.0%), PF (RD:0.003 (-0.007, 0.014), I2: 0.0%), and PC (RD:0.001 (-0.008, 0.010), I2: 0.0%). There were significantly higher biological complications (RD: -0.071 (-0.106, -0.036), I2: 0.82.9%) for ST compared to SH in both jaws up to a 10-year follow-up.

CONCLUSION

SH and ST had comparable overall outcomes, but short implants had less marginal bone loss and lower biological complications. However, more research is needed to confirm these findings.

Clinical Evaluation of Short (6 mm) and Longer Implants Placed Side by Side in Posterior Partially Edentulous Area: A 3-Year Observational Study

Background

Short implants have been proposed as an alternative solution for the rehabilitation of atrophic posterior region.

Purpose

To compare the clinical outcomes between 6 mm short implants and conventional implants placed under similar conditions of bone quality and occlusal loading.

Materials and Methods

Nine patients received atone 6 mm implant and one standard-length (8 mm length or longer) implants in a total of 10 partially edentulous areas. Implants were left submerged for 3-6 months healing period and the screw-retained splinted prostheses were delivered. When the provisional or final restoration was placed, and at each year after loading, standardized intraoral radiograph was taken for themarginal bone level (MBL) changes around the implants. Subsequently, the patients were recalled for the clinical examination evaluating the implant survival, sulcus bleeding index, suppuration, and the incidence of prosthetic complications at every 6 months after the definitive crown delivery. The observation period was continued to 3 years (mean follow-up was 3.4 ± 0.3 years) after functional loading.

Results

Nine patients (10 short implants and 10 standard length implants) were selected in this study. Cumulative survival rates of the short implants and standard-length implants were 100% in both groups, and no biological and prosthetic complication were found in 3 years observation period. Cortical bone thickness of implant insertion sites was 1.39 ± 0.45 mm at short implants and 1.38 ± 0.69 mm at standard-length implants, and trabecular bone computed tomography values of implant insertion sites was 424.1 ± 290.1 at short implants and 410.9 ± 267.9 at standard-length implants. The MBL changes were -0.30 ± 0.71 mm at short implants and -0.19 ± 0.78 mm at standard-length implants at 3 years follow-up visit. No significant difference was found in the average of MBL changes between implant length.

Conclusions

Within the limits of this study, it can be concluded that 6 mm short implants in a posterior edentulous region showed excellent results compared with conventional implants.

The use of autologous bone for augmentation procedures leads to low prevalence of peri-implantitis-a retrospective study over a 20-year period

The aim of this study was to compare the prevalence of peri-implantitis in implants inserted into pristine bone (control) to implants where autologous bone was used for grafting procedures (study). All patients who underwent implant surgery during a 20 years interval by one maxillofacial implant surgeon and received a prosthodontic rehabilitation afterwards were eligible for inclusion in the study. Periimplant bone resorption and periimplant disease were assessed. Of 421 patients 384 (91.2%) patients responded to a recall after having been treated over a 20-year period by one maxillofacial surgeon and several dentists. A total of 110 patients had 239 implants in pristine bone, and 274 patients had 607 implants placed in combination with autologous bone grafting procedures. Mean time in function was 74 months (range 15-236 months). In all, 342 implants (34.8%) were in function for longer than 7 years. A total of 64 implant sites (7.6%) in 39 patients (10.2%) showed signs of peri-implant mucositis. In addition, 17 implants (2.0%) in 14 patients (3.6%) revealed signs of peri-implantitis, of which five implants were in the control group (2.09%) whereas 12 implants were in the study group (1.98%), with no statistically significant difference (p = 0.8405). More than half of the patients with peri-implantitis had a history of periodontitis. Three implants were lost due to peri-implantitis and four implants failed for other reasons, resulting in an overall success rate of 99.2% in 846 implants. CONCLUSIONS: Within the limitations of the study it seems that the use of autologous bone still is a relevant option when performing augmentation procedures because of the low prevalence of peri-implantitis.

Short Implants versus Standard Implants and Sinus Floor Elevation in Atrophic Posterior Maxilla: A Systematic Review and Meta-Analysis of Randomized Clinical Trials with ≥5 Years' Follow-Up

Background and objectives: The aim of this systematic review with meta-analysis was to assess the performance of short implants in comparison with standard implants and sinus floor elevation in atrophic posterior maxilla. Materials and methods: The protocol of the study was registered in the PROSPERO database (CRD42022375320). An electronic search on three databases (PubMed, Scopus, Web of Science) was performed to find randomized clinical trials (RCTs) with ≥5 years' follow-up, published until December 2022. Risk of bias (ROB) was calculated using Cochrane ROB. A meta-analysis was performed for primary (implant survival rate, ISR) and secondary outcomes (marginal bone loss, MBL; biological and prosthetic complications). Results: Of 1619 articles, 5 RCTs met the inclusion criteria. The ISR showed a risk ratio (RR) of 0.97 [0.94, 1.00] (CI 95%), p = 0.07. The MBL indicated a WMD of -0.29 [-0.49, -0.09] (CI 95%), p = 0.005. Biological complications showed a RR of 0.46 [0.23, 0.91] (CI 95%), p = 0.03. Prosthetic complications showed a RR of 1.51 [0.64, 3.55] (CI 95%), p = 0.34. Conclusions: The available evidence suggests that short implants might be used as an alternative to standard implants and sinus floor elevation. After 5 years, in terms of ISR, standard implants and sinus floor elevation showed a higher survival rate comparted to short implants, although statistical significance was not achieved. Future RCTs with long-term follow-up are needed to draw a clear conclusion on the advantages of one method over another.

Short versus standard implants at sinus augmented sites: a systematic review and meta-analysis

BACKGROUND

Short implants are proposed as a less invasive alternative with fewer complications than standard implants in combination with sinus lift. The aim of this systematic review and meta-analysis was to state the efficacy of placing short implants (≤ 6 mm) compared to standard-length implants (≥ 8 mm) performing sinus lift techniques in patients with edentulous posterior atrophic jaws. Efficacy will be evaluated through analyzing implant survival (IS) and maintenance of peri-implant bone (MBL).

METHODS

Screening process was done using the National Library of Medicine (MEDLINE by PubMed), EMBASE, the Cochrane Oral Health, and Web of Science (WOS). The articles included were randomized controlled trials. Risk of bias was evaluated according to The Cochrane Collaboration's tool. Weighted means were calculated. Heterogeneity was determined using Higgins (I²). A random-effects model was applied. Secondary outcomes such as surgical time, patient satisfaction, mucositis and peri-implantitis, pain, and swelling were analyzed.

RESULTS

Fourteen studies (597 patients and 901 implants) were evaluated. IS was 1.02 risk ratio, ranging from 1.00 to 1.05 (CI 95%) (p = 0.09), suggesting that IS was similar when both techniques were used. MBL was higher in patients with standard-length implants plus sinus lift elevation (p = 0.03). MBL was 0.11 (0.01-0.20) mm (p = 0.03) and 0.23 (0.07-0.39) mm (p = 0.005) before and after 1 year of follow-up, respectively, indicating that the marginal bone loss is greater for standard-length implants.

DISCUSSION

Within the limitations of the present study, as relatively small sample size, short dental implants can be used as an alternative to standard-length implants plus sinus elevation in cases of atrophic posterior maxilla. Higher MBL was observed in the groups where standard-length implants were used, but implant survival was similar in both groups. Moreover, with short implants, it was observed a reduced postoperative discomfort, minimal invasiveness, shorter treatment time, and reduced costs.

CLINICAL CLINICAL RELEVANCE

The low MBL promoted by short implants does contribute to a paradigm shift from sinus grafting with long implants to short implants. Further high-quality long-term studies are required to confirm these findings.

Survival of surface-modified short versus long implants in complete or partially edentulous patients with a follow-up of 1 year or more: a systematic review and meta-analysis

PURPOSE

Short implants are a potential alternative to long implants for use with bone augmentation in atrophic jaws. This meta-analysis investigated the survival rate and marginal bone level (MBL) of surface-modified short vs. long implants.

METHODS

Electronic and manual searches were performed for articles published between January 2010 and June 2021. Twenty-two randomized controlled trials (RCTs) comparing surface-modified short and long implants that reported the survival rate with at least 1 year of follow-up were selected. Two reviewers independently extracted the data, and the risk of bias and quality of evidence were evaluated. A quantitative meta-analysis was performed regarding survival rate and MBL.

RESULTS

The failure rates of surface-modified short and long implants differed significantly (risk ratio, 2.28; 95% confidence interval [CI], 1.46, 3.57; P<0.000). Long implants exhibited a higher survival rate than short implants (mean follow-up, 1-10 years). A significant difference was observed in mean MBL (mean difference=-0.43, 95% CI, -0.63, -0.23; P<0.000), favoring the short implants. Regarding the impact of surface treatment in short and long implants, for hydrophilic sandblasted acid-etched (P=0.020) and titanium oxide fluoride-modified (P=0.050) surfaces, the survival rate differed significantly between short and long implants. The MBL differences for novel nanostructured calcium-incorporated, hydrophilic sandblasted acid-etched, and dual acid-etched with nanometer-scale calcium phosphate crystal surfaces (P=0.050, P=0.020, and P<0.000, respectively) differed significantly for short vs. long implants.

CONCLUSIONS

Short surface-modified implants are a potential alternative to longer implants in atrophic ridges. Long fluoride-modified and hydrophilic sandblasted acid-etched implants have higher survival rates than short implants. Short implants with novel nanostructured calcium-incorporated titanium surfaces, hydrophilic sandblasted acid-etched surfaces, and dual acid-etched surfaces with nanometer-scale calcium phosphate crystals showed less marginal bone loss than longer implants. Due to high heterogeneity, the MBL results should be interpreted cautiously, and better-designed RCTs should be assessed in the future.

TRIAL REGISTRATION

International Prospective Register of Systematic Reviews (PROSPERO) Identifier: CRD42020160185.

Short Implants versus Longer Implants with Sinus Floor Elevation: A Systemic Review and Meta-Analysis of Randomized Controlled Trials with a Post-Loading Follow-Up Duration of 5 Years

This study compared the outcome of fixed prostheses supported by short implants (<8 mm) and longer implants (≥8 mm) with an elevated sinus floor after 5 years of follow-up. The literature searches were performed electronically and manually in PubMed, EMBASE, and Web of Science databases to identify relevant articles published from 1 January 2013 to 31 January 2020. We selected eligible studies using inclusion criteria and assessed their quality. From 1688 identified studies, five randomized controlled trials were included. Between the short implant group and the control group, the implant failure-related pooled risk ratio (RR) was 3.64 (p = 0.07). The RR for technical complications was 2.61 (p = 0.0002), favoring longer implants. Marginal peri-implant bone loss after 1 and 5 years of function showed statistically significant less bone loss at short implants (1 year: mean difference = 0.21 mm; p < 0.00001; 5 years: mean difference = 0.26 mm; p = 0.02). The implant failure and the biological failure of both groups were similar after 5 years of follow-up. Short implants could be an alternative to long implants with an elevated sinus floor for atrophic maxillae in aging populations. Studies with larger trials and longer periods of follow-up (10 years) remain essential.

A prospective, multicentre study of 6-mm short implants in posterior alveolar bone supporting splinted crowns: A 5-year follow-up study

AIM

To evaluate the clinical and radiographic outcomes of 6-mm short implants, placed in the posterior jaws and supporting splinted crowns, at 5 years after early loading.

MATERIALS AND METHODS

Forty-five patients with 95 implants (diameter: 4 mm; length: 6 mm) were enrolled at three centres. Two to three implants were placed in either the maxillary or the mandibular posterior region in each patient and restored with screw-retained splinted crowns at 6 weeks later. Clinical and radiographic outcomes were evaluated at implant placement, at loading, and at 6, 12, 24, 36, and 60 months after loading. Biological and mechanical complications were recorded. Marginal changes in bone level in relation to clinical parameters were evaluated using a generalized linear mixed model.

RESULTS

During the 5 years of follow-up, the mean change in the marginal bone level (MBL) was 0.04 ± 0.14 mm. Four implants in four patients were lost before loading, one implant in one patient was lost at the 5-year follow-up, and two patients were lost to follow-up. The survival and success rates were 88.4% (38/43) at the patient level. The incidence rates of peri-implant mucositis and peri-implantitis were 29.4% and 7.0%, respectively. The rate of technical complications was 14.0%.

CONCLUSIONS

Over a 5-year period, 6-mm short implants supporting early loaded splinted crowns in maxillary or mandibular posterior regions showed stable MBLs and acceptable technical and biological complication rates.

Long-term clinical outcomes of short implant (6mm) in relation to Implant Disease Risk Assessment (IDRA)

AIM

To evaluate the long-term survivals of short implants and to investigate the association of the Implant Disease Risk Assessment (IDRA) with the occurrence of biological complications.

MATERIAL AND METHODS

This study was designed as a cohort study with a median follow-up of 10.0 years. Patients who had received 6-mm implants were reviewed and assigned into low-, moderate- and high-risk groups (Group L, M and H) based on the IDRA tool. The implant survival, biological complications, soft tissue condition, hardware complications and marginal bone loss (MBL) were evaluated. Kaplan-Meier curves and Cox regression were performed for survival analysis.

RESULTS

A hundred and ten patients were included. The overall cumulative survival rate was 90.9% (L:100.0%, M: 93.3% and H: 80.6%). A higher risk profile was significantly associated with a decreased implant survival (hazard ratio: 4.11, 95% CI: 1.17-14.36, p<0.05). Higher risk profile (hazard ratio: 2.63, 95% CI: 1.32-5.25, p<0.05) was a potential risk factor for biological complications. At follow-up, significant differences in bleeding index, modified plaque index and peri-implant probing depth were found among groups (p<0.01). No significant difference was found in MBL.

CONCLUSION

Acceptable long-term clinical outcomes could be achieved after 10 years for short implants. Despite a statistically nonsignificant difference in MBL, patients with a high-risk profile of IDRA seem to be at greater risk of implant loss and biological complications.

Professional and patient-reported outcomes of two surgical approaches for implant-supported single-crown restoration: 1-year results of a randomized controlled clinical trial

OBJECTIVES

To test whether there is a difference in professional and patient-reported outcome measures (PROM) after single-crown restoration supported by short implants (SI) (6 mm) compared with standard length implants (SLI) (13 mm) in conjunction with maxillary sinus floor augmentation (MSFA) after 1 year of functional implant loading.

MATERIAL AND METHODS

Forty patients were randomly allocated to SI or SLI/MSFA. PROM included Oral Health Impact Profile (OHIP-14) questionnaire and subjective assessment of the peri-implant soft tissue (A), implant crown (B), implant function (C) and overall implant treatment outcome (D) using visual analogue scale (VAS). Professional assessment included pink aesthetic score (PES) and white aesthetic score (WES).

RESULTS

No significant differences in professional or PROM between the two treatment modalities were revealed at any time point (p > .05). OHIP-14 score decreased at baseline and 1 year after functional implant loading compared with preoperative measurements indicating improved quality of life with both treatment modalities. The 1-year mean VAS score was 9.4 (A), 9.3 (B), 9.6 (C) and 9.3 (D) for SI compared with 9.3 (A), 9.6 (B), 9.7 (C) and 9.2 (D) for SLI. The 1-year mean PES/WES scores were 11.3 and 8.1 for SI compared with 11.2 and 8.1 for SLI/MSFA.

CONCLUSIONS

Prosthetic rehabilitation of the posterior part of the maxilla with SI or SLI/MSFA revealed no significant differences in professional and PROM after 1 year of implant loading.

Posterior jaws rehabilitation with < 7mm-short implants. A review

INTRODUCTION

The results with shorter and shorter implants have been revolutionizing the implantology scenario and are worthy of being well-analyzed and understood. This review aims to add further knowledge about the last 10-years observation period on < 7mm-short implants in the posterior atrophic jaws, better defining the indication of their use.

METHODS

From a Medline database research, systematic reviews, controlled and no- controlled trials (CT, n-CT) with ≥ 3years-follow-ups on <7 mm / ≥ 5mm-short implants (group A), and clinical studies with ≥ 1year-follow-up on 4mm-short implants (group B) were considered. The outcomes, in terms of implant survival rate (SR), marginal bone loss (MBL), and complications were analyzed according to the duration of follow-ups, implant site (maxilla and mandible), type of prosthesis (single crown or splinted units), vertically impaired or normal sites.

RESULTS

Thirty-four trials (28 for group A and six for group B) were selected. Group A: a mean follow up of 5,8 (3-10) years came out; pre-and post-loading SR range was 94.4- 100% and 89.6-100%, respectively; the range of MBL was 0.12-1.49; 50% of CT found less statistically significant surgical complications in comparison with standard implants (ST) in reconstructed sites, while major prosthetic problems were recorded with short -implants (SH) in 37.5% of CT; in no atrophied sites, a mean SR range of 86.7-100 % vs. 88-100 % and a total bone loss of 2 vs.1.6 for SH vs.ST emerged. Group B: the overall mean follow-up period was 2,3 years, and the pre-and post- SR ranges were 93-100 % and 87.5-100 %, respectively. The MBL range was 0.02- 0.63 mm. All RCT reported significantly fewer surgical complications with SH than with ST in reconstructed mandibles within one year. No prosthetic complications were reported for up to 5 years using no pontics or cantilevers fixed bridges.

CONCLUSIONS

Similar or even better results for SH than ST in terms of post-loading SR and MBL came out for < 7mm/ ≥ 5mm-short implants in atrophic bone regardless of the prosthetic solutions, with less surgical complications but a few more prosthetic problems; the good results up to 5 years for 4mm-short implants in mandibles are associated with splinted and no-risk prosthetic solutions.

A 4 mm-Long Implant Rehabilitation in the Posterior Maxilla with Dynamic Navigation Technology: A Case Report after a Three-Years Post-Loading Follow-Up

The use of short (<8 mm long) and ultra-short (<6 mm long) implants allows the prosthetic rehabilitation of the posterior ridges of the jaws avoiding reconstructive procedures. Nevertheless, this approach requires vast experience to ensure the primary stability of the fixture in a correct position. Computer-aided implantology (CAI) achieves better results than the free-hand one in terms of placement accuracy, reducing the surgical risks and the operative timings. Dynamic navigation (DN) allows the surgeon to track the position and movements of the drill in real-time on the CT imaging data set. It is more versatile than the computed static system, enabling the operator to change the guidance coordinates according to the intra-operative feedbacks. A mono-edentulous upper right first molar site was rehabilitated with a four mm-long implant to avoid reconstructive techniques, drastically rejected by the patients. The case was managed within a DN protocol considering the minimal available bone and the prosthetic demands. The phases of this procedure were strictly documented up to a 3-year follow-up. No intra-operative problems occurred, and adequate primary stability of the implant was obtained. The prosthetic loading was carried out within only six weeks without any complications. No variation of the baseline clinical scenario as evidenced clinically and radiographically at the end of follow-up. No similar cases are reported in the literature.

Two short implants versus one short implant with a cantilever: 5-Year results of a randomized clinical trial

Aim

To test whether or not the use of a short implant with a cantilever results in similar clinical and radiographic outcomes compared to two adjacent short implants with single tooth reconstructions.

Materials and methods

Thirty‐six patients with two adjacent missing teeth in the posterior region were randomly assigned to receive either a single 6‐mm implant with a cantilever (ONE‐C) or two 6‐mm implants (TWO). Fixed reconstructions were inserted 3–6 months after implant placement and patients were re‐examined up to 5 years (FU‐5).

Results

A total of 26 patients were available for re‐examination at FU‐5. The survival rate amounted to 84.2% in ONE‐C and to 80.4% in TWO (inter‐group: p = .894). Technical complication rates amounted to 64.2% (ONE‐C) and to 54.4% (TWO) (inter‐group: p = 1.000). From baseline to FU‐5, the median changes of the marginal bone levels were 0.13 mm in ONE‐C and 0.05 mm in TWO (inter‐group: p = .775). Probing depth, bleeding on probing, and plaque control record values showed no significant differences between the two treatment modalities (p > .05).

Conclusions

Short implants with a cantilever render similar clinical and radiographic outcomes compared to two adjacent short implants at 5 years, however, they tend to fail at earlier time points suggesting an overload of the implants. Considering the modest survival rates, the clinical indication of either treatment option needs to be carefully evaluated. ClinicalTrials.gov (NCT01649531).

Clinical performance of short versus standard dental implants in vertically augmented bone: an overview of systematic reviews

OBJECTIVE

To answer the question: What do we know so far about the clinical performance of short implants (≤ 7 mm) when compared to standard length implants in vertically augmented bone, as well as which is the overall confidence of the systematic reviews (SRs) about this topic?

MATERIALS AND METHODS

An overview of SRs was conducted. The searches were performed in six electronic databases and grey literature. SRs about short (≤ 7 mm) versus standard dental implants performance in vertically augmented bone were included. The assessed outcomes were marginal bone loss (MBL), implant survival (IS), prosthetic (PC) and biological complications (BC), costs, surgical time, and patient satisfaction. AMSTAR 2 was used to evaluate the overall confidence of included SRs.

RESULTS

Thirteen SRs were included. Nine of twelve SRs reported a lower MBL for the short implant group. All the included SRs showed no difference in the IS between groups. A higher rate of BC was reported for standard-length implants in four out of five SRs. No differences regarding PC were reported in four of five SRs. Information related to patient preference, cost, and surgery time were underreported. The confidence evaluation of the SRs was stratified as low for five SRs and critically low for eight SRs.

CONCLUSIONS

In an overall low-to-very low confidence levels, short implants appear to perform better in the mid-term (up to 5 years) than standard dental implants associated with vertical bone augmentation regarding MBL and BC, but they have a similar performance regarding IS rates and PC. There is an imperative need to improve the methodological quality of SRs, and efforts should focus on conducting RCTs to broaden the knowledge on this topic.

CLINICAL RELEVANCE

Short implants could represent a viable, simpler, and less invasive treatment when available bone height is limited.

Single-crown restorations supported by short implants (6 mm) compared with standard-length implants (13 mm) in conjunction with maxillary sinus floor augmentation: a randomized, controlled clinical trial

Background

The purpose of the present study was to test the H0-hypothesis of no difference in the clinical and radiographical treatment outcome of single-crown restorations supported by short implants compared with standard length implants in conjunction with maxillary sinus floor augmentation (MSFA) after 1 year of functional implant loading. Forty patients with partial edentulism in the posterior part of the maxilla were randomly allocated to treatment involving single-crown restorations supported by short implants or standard length implants in conjunction with MSFA. Clinical and radiographical evaluation were used to assess survival of suprastructures and implants, peri-implant marginal bone loss (PIMBL), biological, and mechanical complications.

Results

Both treatment modalities were characterized by 100% survival of suprastructures and implants after 1 year. Mean PIMBL was 0.60 mm with short implants compared with 0.51 mm with standard length implants after 1 year of functional loading. There were no statistically significant differences in survival of suprastructure and implants, PIMBL, and mechanical complications between the two treatment modalities. However, a higher incidence of biological complications was associated with standard length implants in conjunction with MSFA.

Conclusion

Within the limitations of the present study, it can be concluded that single-crown restorations supported by short implants seems to be comparable with standard length implants in conjunction with MSFA. However, long-term studies are needed before final conclusions can be provided about the two treatment modalities.

Trial registration

Clinicaltrials.Gov ID: NCT04518020. Date of registration: August 14, 2020, retrospectively registered.

Osseodensification effect on implants primary and secondary stability: Multicenter controlled clinical trial

Background

Osseodensification (OD) has shown to improve implant stability; however, the influences of implant design, dimensions, and surgical site characteristics are unknown.

Purpose

To compare the insertion torque (IT) and temporal implant stability quotients (ISQ) of implants placed via OD or subtractive drilling (SD).

Materials and Methods

This multicenter controlled clinical trial enrolled 56 patients, whom were in need of at least 2 implants (n = 150 implants). Patients were treated with narrow, regular, or wide implants and short, regular, or long implants in the anterior or posterior region of the maxilla or in the posterior region of the mandible. Osteotomies were performed following manufacturers recommendation. IT was recorded with a torque indicator. ISQ was recorded with resonance frequency analysis immediately after surgery, 3 and 6 weeks.

Results

Data complied as a function of osteotomy indicated significantly higher IT for OD relative to SD. OD outperformed conventional SD for all pairwise comparisons of arches (maxilla and mandible) and areas operated (anterior and posterior), diameters and lengths of the implants, except for short implants. Overall, ISQ data also demonstrated significantly higher values for OD compared to SD regardless of the healing period. Relative to immediate readings, ISQ values significantly decreased at 3 weeks, returning to immediate levels at 6 weeks; however, ISQ values strictly remained above 68 throughout healing time for OD. Data as a function of arch operated and osteotomy, area operated and osteotomy, implant dimensions and osteotomy, also exhibited higher ISQ values for OD relative to SD on pairwise comparisons, except for short implants.

Conclusions

OD demonstrated higher IT and temporal ISQ values relative to SD, irrespective of arch and area operated as well as implant design and dimension, with an exception for short implants. Future studies should focus on biomechanical parameters and bone level change evaluation after loading.

Short Dental Implants (≤8.5 mm) versus Standard Dental Implants (≥10 mm): A One-Year Post-Loading Prospective Observational Study

Background: Recent data have shown that short dental implants can be the preferred treatment in most of cases of posterior atrophic alveolar ridges, offering higher survival and lower complication rates than long implants. The survival rates, stability, and marginal bone level changes were compared between short implants (7 and 8.5 mm) and standard-length implants (≥10 mm). Methods: Prospective observational study in which adult patients requiring ≥1 osseointegrated implants to replace missing teeth were recruited consecutively. A clinical examination was performed on the day the definitive prosthesis was placed and after 6 and 12 months. Implant stability quotient (ISQ), marginal bone level (MBL) changes, and the correlation between these parameters and the characteristics of the implants were evaluated. Results: A total of 99 implants were inserted (47 short, 52 standard) in 74 patients. The 12-month survival rate was 100%. ISQ values showed a similar pattern for both types of implants. No correlation was found between ISQ changes after one year and MBL values, nor between the latter and the characteristics of the implants. Conclusions: With clinical treatment criteria, shorter implants (7 and 8.5 mm in length) can be just as useful as standard-length implants in atrophic alveolar ridges, demonstrating similar rates of survival, stability, and crestal bone loss.

Clinical Outcome of Dental Implants after Maxillary Sinus Augmentation with and without Bone Grafting: A Retrospective Evaluation

(1) Background: The purpose of the present study was to retrospectively evaluate and compare the outcome of two sinus augmentation grafting protocols using a xenograft or blood clot alone over a 72-month follow-up. (2) Methods: Patients who received simultaneous lateral sinus floor augmentation and implant placement were included. Subjects were divided into two groups according to the grafting material, namely xenograft or blood clot, and into sub-groups based on the residual alveolar bone height (RABH) below the maxillary sinus, namely 4 to 6 mm or >6 mm. Kaplan-Meier survival estimates were calculated for each material group and for each sub-group at 1, 3, and 6 years. (3) Results: In total, 289 implants inserted in 136 patients with a one-stage procedure were considered. A total of 35 failures were registered. Overall survival rates were 94.2% for xenograft and 85.9% for blood clot alone at 1 year, 91.1% and 81.6% at 3 years, and 91.1% and 78.7% at 6 years. (4) Conclusions: In patients with 4-6 mm RABH, graftless interventions exploiting blood clot alone were not as successful as those using xenograft. When the RABH is low, sinus floor augmentation associated with grafting materials should be preferred whenever possible.

Implant-based oral rehabilitation in systemic sclerosis patients: a systematic review

Systemic sclerosis is a rare multisystem autoimmune disorder that significantly impacts the orofacial region. Several oral features including microstomia and increased tooth loss contribute to the mouth-related disability. Prosthetic rehabilitation is very challenging in these patients. As the spectrum of dental implants indications has been recently extended to patients with various systemic disorders, the aim of this systematic review was to evaluate the outcome of dental implants in patients with systemic sclerosis. A literature search was conducted in Medline/PubMed database to identify eligible case-reports. 10 publications were included in qualitative synthesis. A total of 71 implants have been reported in 10 patients with systemic sclerosis with a mean of 7.1 +/- 3.8 implants per patient. Pre-implant surgeries have been described for 3 patients. Implant survival rates were higher than 98% but the mean follow-up time was only 28.3 +/- 18.6 months. Complications have been observed in 3 patients with 1 implant failure and peri-implant bone resorption in 2 patients. Although implant survival rates were high, an individualized assessment of risk-benefit balance is mandatory before indicating implant-based rehabilitation in patients suffering from systemic sclerosis and a scrupulous maintenance program has to be implemented. Further studies are strongly required to establish clinical guidelines.

A meta-analysis indicating extra-short implants (≤ 6 mm) as an alternative to longer implants (≥ 8 mm) with bone augmentation

Extra-short implants, of which clinical outcomes remain controversial, are becoming a potential option rather than long implants with bone augmentation in atrophic partially or totally edentulous jaws. The aim of this study was to compare the clinical outcomes and complications between extra-short implants (≤ 6 mm) and longer implants (≥ 8 mm), with and without bone augmentation procedures. Electronic (via PubMed, Web of Science, EMBASE, Cochrane Library) and manual searches were performed for articles published prior to November 2020. Only randomized controlled trials (RCTs) comparing extra-short implants and longer implants in the same study reporting survival rate with an observation period at least 1 year were selected. Data extraction and methodological quality (AMSTAR-2) was assessed by 2 authors independently. A quantitative meta-analysis was performed to compare the survival rate, marginal bone loss (MBL), biological and prosthesis complication rate. Risk of bias was assessed with the Cochrane risk of bias tool 2 and the quality of evidence was determined with the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach. 21 RCTs were included, among which two were prior registered and 14 adhered to the CONSORT statement. No significant difference was found in the survival rate between extra-short and longer implant at 1- and 3-years follow-up (RR: 1.002, CI 0.981 to 1.024, P = 0.856 at 1 year; RR: 0.996, CI 0.968 to 1.025, P  = 0.772 at 3 years, moderate quality), while longer implants had significantly higher survival rate than extra-short implants (RR: 0.970, CI 0.944 to 0.997, P < 0.05) at 5 years. Interestingly, no significant difference was observed when bone augmentations were performed at 5 years (RR: 0.977, CI 0.945 to 1.010, P = 0.171 for reconstructed bone; RR: 0.955, CI 0.912 to 0.999, P < 0.05 for native bone). Both the MBL (from implant placement) (WMD: - 0.22, CI - 0.277 to - 0.164, P < 0.01, low quality) and biological complications rate (RR: 0.321, CI 0.243 to 0.422, P < 0.01, moderate quality) preferred extra-short implants. However, there was no significant difference in terms of MBL (from prosthesis restoration) (WMD: 0.016, CI - 0.036 to 0.068, P = 0.555, moderate quality) or prosthesis complications rate (RR: 1.308, CI 0.893 to 1.915, P = 0.168, moderate quality). The placement of extra-short implants could be an acceptable alternative to longer implants in atrophic posterior arch. Further high-quality RCTs with a long follow-up period are required to corroborate the present outcomes.Registration number The review protocol was registered with PROSPERO (CRD42020155342).

Two-Year Follow-Up of 4-mm-Long Implants Used as Distal Support of Full-Arch FDPs Compared to 10-mm Implants Installed after Sinus Floor Elevation. A Randomized Clinical Trial

BACKGROUND

In edentulous patients, bone resorption cannot allow the installation of standard implants and it is demanded to use short implants in the residual alveolar bone or longer implants in grafted bone.

AIM

To compare the survival and bone level changes of standard plus short 4-mm implants used as distal support of a maxillary full-arch fixed dental prostheses (FDPs) with standard (10-mm) implants placed in association with a bilateral sinus floor augmentation procedure.

MATERIAL AND METHODS

Full-arch FDPs supported by six implants were randomly placed in both groups. In the control group, all implants were 10 mm long and 4.1 mm in diameter. The distal implant in both sides of the maxilla was installed after 4 months from bilaterally sinus floor elevation. In the test group (short group), the distal implant in both sides of the maxilla was 4 mm long and 4.1 mm in diameter. No sinus floor elevations were performed in the test group. Clinical assessments and X-rays were taken at prosthesis delivering and after 6, 12, 18, and 24 months. Patient-reported outcome measures (PROMs) were also evaluated before surgery and after 6, 12, and 24 months.

RESULTS

The changes over time of the bone level for the short implants were -0.01 ± 0.11 mm, -0.04 ± 0.13 mm, -0.17 ± 0.29 mm, and -0.28 ± 0.37 mm after 6, 12, 18, and 24 months from prosthesis delivering, respectively. For the standard implants, bone changes were -0.21 ± 0.33 mm (p = 0.103), -0.30 ± 0.32 mm (p = 0.023), -0.40 ± 0.37 mm (p = 0.144), and -0.54 ± 0.49 mm (p = 0.128), respectively. A statistically relevant difference was found only at 12 months after loading between the two groups.

CONCLUSIONS

Similar results on implant survival rate and marginal bone loss were observed for the short and standard implants, placed in association with a bilateral sinus floor augmentation procedure, used as distal support of a maxillary full-arch FDP. A statistically relevant difference was found only at 12 months after loading between the two groups (p = 0.023).

Short communication: Cemented implant reconstructions are associated with less marginal bone loss than screw-retained reconstructions at 3 and 5 years of loading

OBJECTIVES

To analyse whether there is a difference in marginal bone levels (MBL) and the respective changes between cemented and screw-retained reconstructions at 3 and 5 years of loading.

METHODS

Radiographic data from 14 prospective multicentre clinical trials following implant loading with fixed cemented (CEM) or screw-retained (SCREW) reconstructions with a 3- to 5-year follow-up were retrieved from a database. MBL and MBL changes were assessed at initiation of implant loading (BL), at 3 (FU-3) and 5 years (FU-5) thereafter. The presence of peri-implantitis was also determined.

RESULTS

Data from 1,672 implants at BL, 1,565 implants at FU-3 and 1,109 implants at FU-5 were available. The mean MBL amounted to 0.57 mm (SD 0.87) at BL, 0.55 mm (SD 0.86) at FU-3 and 0.65 mm (SD 1.18) at FU-5. At FU-3, the mean MBL was 0.44 mm (SD 0.65) in group CEM and 0.63 mm (SD 0.99) in group SCREW showing a significant difference between the groups (intergroup <0.05). At FU-5, the mean MBL was 0.42 mm (SD 0.77) in CEM and 0.80 mm (SD 1.37) in SCREW, again with significant differences between both groups (p < .05). MBL changes between BL and FU-3 amounted to 0.11 mm (SD 1.02) (bone loss) in SCREW and -0.17 mm (SD 1.03) (bone gain) in CEM. Similarly, mean MBL changes from BL to FU-5 amounted to 0.23 mm (SD 1.31) (bone loss) in SCREW and -0.26 mm (SD 1.27) (bone gain) in CEM. The prevalence of peri-implantitis amounted to 6.9% in CEM and 5.6% in group SCREW (intergroup p = .29063) at FU-3. At FU-5, peri-implantitis amounted to 4.6% in CEM and 6.2% in group SCREW (intergroup p = .28242).

CONCLUSION

Cemented implant reconstructions compared with screw-retained reconstructions revealed higher marginal bone levels and similar rates of peri-implantitis during 5 years. The difference in MBL and the respective changes between the two groups, however, appear to be clinically negligible.

Clinical, radiographic and economic evaluation of short-6-mm implants and longer implants combined with osteotome sinus floor elevation in moderately atrophic maxillae: A 3-year randomized clinical trial

AIM

To compare the 3-year clinical, radiographic and economic outcomes of short-6-mm implants and longer implants combined with osteotome sinus floor elevation (OSFE) in the posterior maxilla.

MATERIAL AND METHODS

This study enrolled 225 patients (225 implants with diameter of 4.1 mm and 4.8 mm) with a posterior maxillary residual bone height (RBH) of 6-8 mm. Patients were randomly divided into three groups: Group 1 (6 mm implants alone), Group 2 (8 mm implants + OSFE) and Group 3 (10 mm implants + OSFE). The following outcomes were recorded at 1 and 3-year examinations: implant survival, probing pocket depth (PPD), bleeding on probing (BOP), modified plaque index (mPI), marginal bone loss (MBL), biological and technical complications, complication-free survival and treatment costs.

RESULTS

At the 3-year follow-up, 199 patients (Group 1: 67; Group 2: 62; Group 3: 70) were re-examined. Implant survival rates were 91.80%, 97.08% and 100.00% in groups 1, 2 and 3. Implant survival rate in Group 1 was significantly lower than that in Group 3 (p = 0.029). A multivariate Cox model showed that the short-6-mm implants with wide diameter had a protective effect on implant survival (hazard ratio: 0.59, p = 0.001). No significant differences in BOP%, PPD, mPI, MBL and complication-free survival rate were found among the three groups. The average costs of retreatment were 8.31%, 1.96% and 0.56% of the total costs in groups 1, 2 and 3. The cost to avoid a 1% increase in implant loss associated with 6-mm implants over a 3-year period was 369 CNY (56 USD) using a 10-mm implant with OSFE and 484 CNY (74 USD) using an 8-mm implant with OSFE.

CONCLUSION

In the moderately atrophic posterior maxillae, the three treatments showed acceptable clinical, radiographic and economic outcomes with up to 3-year follow-up. 10-mm implants combined with OSFE showed more favourable implant survival and fewer maintenance costs in comparison with short-6-mm implants, which were less expensive.

Short (6 mm) and Regular Dental Implants in the Posterior Maxilla-7-Years Follow-up Study

Short 6 mm dental implants are considered as an alternative to the maxillary sinus elevation and bone augmentation procedure where there is a reduced alveolar ridge height. The aim of this study was to compare the implant survival rate between short dental implants (6 mm) and regular length implants (11-13 mm) when placed in combination with bone grafting and loaded with a single non splinted crown, seven years after placing the implant. It was conducted as a controlled clinical study of 30 patients with partial edentulism in the posterior maxilla. The protocol included radiological and clinical evaluation of the C/I ratio (length of the superstructure divided by the length of the implant crestal part), marginal bone level (MBL), ultrasonography measurement of soft tissue surrounding implant (STT), patient-reported outcomes, and biological and technical complications. A total number of 28 implants (93%) remained integrated during follow-up period. MBL of 0.50 and 0.52 mm was observed for short implants and regular implants, respectively. MBL was checked for correlation with STT, and a negative correlation was found between MBL: STT. Our study has demonstrated a significantly lower implant survival rate for short implants compared to regular implants (87% compared to 100%). Despite the loss of several implants, good clinical results were achieved in the remaining implants in both groups. It is, therefore, worth considering short implants as an alternative to regular implants with a sinus lift surgery.

Short implants (≤6mm) as an alternative treatment option to maxillary sinus lift

The aim of this systematic review was to evaluate survival rate of short dental implants placed in the posterior area of the maxilla. The electronic literature search of studies published between January 1, 2010 and February 29, 2020 was performed using specific word combinations. The outcome was to meta-analyse the implant survival rate (ISR). The search generated 238 potential studies. After screening procedures, only nine randomized controlled trials fulfilled the inclusion criteria and were selected for qualitative and quantitative analysis. ISR of short implants ranged from 91.9% to 100%, while standard-length implants ISR ranged from 82.9% to 100% with a follow-up from 1 to 5 years in function. The risk ratio difference was 1.24 (95% confidence interval: 0.63-2.45, P=0.52) for short dental implants failure when compared with standard dental implants, and was not statistically significant. Based on the evidence of the included studies, short implants (≤6mm) reported high survival rates over short to medium follow-up in posterior maxilla, but the long-term success is as yet not demonstrated.

The rehabilitation of posterior atrophic maxilla by using the graftless option of short implant versus conventional long implant with sinus graft: A systematic review and meta-analysis of randomized controlled clinical trial

Aim

The purpose of systematic review and meta-analysis was to compare the efficacy of short implant versus conventional long implant with sinus graft in patients rehabilitated for posterior atrophic maxilla.

Setting and Design

Systematic review and meta analysis.

Materials and Methods

Electronic searches were conducted in Pub Med, Embase, and Medline with supplemented by manual search up to December 2019. The randomized controlled trial (RCTs) comparing short implant (<8.5 mm) and long implant (>8.5 mm) with sinus graft were included. (Prospero CRD42020186972).

Statistical Analysis Used

Random-effect model, fixed-effect model, A funnel plot and the Egger's test.

Results

Twenty-two Randomized controlled trials (RCTs) were assessed with 667 patients and 1595 implants (short implant:767, Long implant:835). No significant difference of implant survival rate was recorded for short and long implant (at patient level: RR: 1.01, 95% CI = 0.52-2.0, P = 0.87, I2 = 0%, at implant level RR = 1.09, 95% CI = 0.6-2.0, P = 0.7, I2 = 0%). Similarly marginal bone resorption was reported no difference for short and long implant (MD = 0.16. 95% CI: -0.23 = -0.08, P = 0.00, I2 = 74.83%). Biological complications were marginally higher for long implant (RR = 0.48, 95% CI = 0.23-0.8, P = 0.13, I2 = 29.11%). and prosthetic complications were marginally higher for short implants (RR=1.56, 95% CI=0.85-3.15, P = 0.43, I2 = 0%).

Conclusion

There was no significance difference in implant survival rate and marginal bone resorption recorded for both the short implant and long implant with sinus graft, in the patients rehabilitated with posterior atrophic maxilla. Hence, short implant is a suitable alternative to long implant with sinus graft, for the rehabilitation posterior atrophic maxilla.

Comparison of 6-mm and 11-mm dental implants in the posterior region supporting fixed dental prostheses: 5-year results of an open multicenter randomized controlled trial

Objective

The aim of this multicenter, randomized controlled trial was to compare the clinical and radiographic outcomes of 6‐mm or 11‐mm implants, placed in the posterior maxilla and mandible, during a 5‐year follow‐up period.

Materials and methods

Ninety‐five patients with adequate bone height for 11‐mm implants, were randomly allocated to a 6‐mm group (test group with short implants) or an 11‐mm group (control group with standard‐length implants). Two or three implants of the same length were placed in each patient and after 6 weeks loaded with a splinted provisional restoration. This was followed by definitive splinted restoration 6 months after implant placement. Clinical and radiographic parameters, including the occurrence of complications were recorded.

Results

A total of 49 patients were enrolled to receive 6‐mm implants (n = 108) and 46 patients to receive 11‐mm implants (n = 101). Three implants (two of 6 mm and one of 11 mm in length) were lost before loading and one 6‐mm implant after 15 months of function, and one 11‐mm implant was lost during the first year of function. The 5‐year survival rates were 96.0% and 98.9% in the 6‐mm and 11‐mm group, respectively. The mean marginal bone level changes 5 years post‐loading were 0.01 ± 0.45 mm (bone gain) in the 6‐mm group and −0.12 ± 0.93 mm (bone loss) in the 11‐mm group (p = .7670). Clinical parameters, including plaque, bleeding on probing and pocket probing depth were not significantly different between the groups, and also technical complications were low.

Conclusion

The clinical and radiographic outcomes of 6‐mm short and 11‐mm standard‐length implants were not different during a 5‐year evaluation period.

Key factors influencing short implant success

AIM

This systematic article reviews the literature on the confounding parameters that affect short implant survival in order to establish specific surgical and prosthetic protocols that create an optimal biomechanical scenario and ensure implant longevity.

MATERIALS AND METHODS

The available literature was screened for randomized clinical trials and prospective cohort and retrospective studies, published up to February 20, 2020, on the prognosis of short-length implants placed in posterior jaws. Studies evaluating the 5-year clinical performance of short dental implants (5 mm or 6 mm) in fixed rehabilitations of partially edentulous posterior jaws were included.

RESULTS

Eleven studies were selected after assessment of inclusion and exclusion criteria, of which 8 were RCTs, 2 were prospective studies, and 1 was a retrospective study. After 5 years in function, 22 short (12 in maxilla and 10 in mandible) and 10 standard (2 in maxilla and 8 in mandible) implants were lost, resulting in high survival rates independent of implant length or location. More biological complications were found in standard implants especially those placed in augmented posterior mandibles (135 complications compared to 48 in short mandibular implants). Splinted prostheses were associated with less technical complications (15 out of 53 complications affecting short implants).

CONCLUSION

The findings of this review showed that, when used correctly, short implants achieve predictable and promising long-term outcomes, provided they are placed following a comprehensive surgical and prosthetic protocol, based on the different biomechanical parameters essential to optimize long-term prognosis.

CLINICAL SIGNIFICANCE

The use of short implants in clinical practice has considerably increased in a wide variety of cases, given that they offer several advantages for both patient and practitioner. Recent literature shows that, when specific criteria are respected, new generations of short implants present high, long-term survival rates. This review is designed to provide a thorough understanding of the surgical and prosthetic protocols that create an optimal biomechanical scenario for short implants and improve their prognosis.

Short implants versus longer implants in the posterior alveolar region after an observation period of at least five years: A systematic review and meta-analysis

OBJECTIVES

This meta-analysis compared clinical outcomes, including survival rate, marginal bone loss (MBL), and technical and biological complications of short implants (<7 mm) and long implants (≥7 mm) placed in the posterior alveolar bone.

SOURCES

Electronic (via PubMed, EMBASE, Cochrane Library) and manual searches were performed for articles published prior to November 29, 2019.

STUDY SELECTION

The review protocol was registered with PROSPERO (CRD42019140718). Only randomized controlled trials (RCTs) comparing short implants and standard implants in the same study after an observation period of at least five years were included.

DATA

Nine RCTs were included in this study. The survival rates of short implants (<7 mm) ranged from 86.7 %-98.5 %, whereas the survival rates of longer implants (≥7 mm) were 95.1%-100% with follow-up ranging from 5 to 10 years. Dichotomous variables were compared using the Mantel-Haenszel (MH) method, and continuous variables were compared using the inverse variance (IV) method. The random effects model and the fixed effects model were used. Meta-analyses showed that short implants had a poorer survival rate than longer implants (P = 0.008). Short implants were associated with lower MBL than longer implants (P < 0.001). The biological complications of short implants were lower (P < 0.001) and the technical complications were higher, than those of long implants (P = 0.006).

CONCLUSIONS

The results indicate that although the survival rate of short implants in the maxilla may be lower than that of long implants, the survival rate of short implants in the mandible is similar to that of long implants, and short implants can result in a lower rate of biological complications. The conclusions should be interpreted with caution due to the limited numbers of participants and implants.

CLINICAL SIGNIFICANCE

When selecting the length of implants, surgeons should consider survival rate, the location of implant placement, their own clinical experience, and the incidence of complications.

Short implants (<8mm) versus longer implants (≥8mm) with lateral sinus floor augmentation in posterior atrophic maxilla: A meta-analysis of RCT`s in humans

BACKGROUND

One of the greatest challenges that dentists face today is to rehabilitate severe atrophied alveolar ridges in partially and completely edentulous patients with implants. Despite the high survival rate of implants placed next to sinus elevation, this technique presents complications that can be avoided by placing short implants, an option that also presents high survival rates. For this reason, the aim of this study is to compare the survival rate, marginal bone loss and complications associated with short implants (<8 mm) versus longer implants (≥8mm) placed with lateral sinus floor elevation in posterior atrophic maxillae.

MATERIAL AND METHODS

A literature search was conducted by two independent reviewers in the PubMed/Medline (National Library of Medicine, Washington, DC) electronic database for articles published from January 2007 to July 2018. Seven qualified articles were selected for the meta-analysis.

RESULTS

The test for overall effect did not find statistical significance in the survival rates, overall complications, intra-operative complications, post-operative complications and prosthetic complications. However, the test showed statistically significant differences in biological complications in favor of standard implants, and marginal bone loss between control and test groups in favor of short implants (<8mm) was found.

CONCLUSIONS

Within the limitations of the present study, prosthetic rehabilitations with short implants (<8mm) in posterior maxilla is a reliable treatment option as an alternative to lateral wall sinus floor augmentation.

Annual review of selected scientific literature: A report of the Committee on Scientific Investigation of the American Academy of Restorative Dentistry

This comprehensive review of the 2018 dental literature is provided to inform busy dentists about progress in the profession. Developed by the Committee on Scientific Investigation of the American Academy of Restorative Dentistry, each author brings discipline-specific expertise to one of the 8 sections of the report including (1) prosthodontics; (2) periodontics, alveolar bone, and peri-implant tissues; (3) implant dentistry; (4) dental materials and therapeutics; (5) occlusion and temporomandibular disorders; (6) sleep-related breathing disorders; (7) oral medicine and oral and maxillofacial surgery; and (8) dental caries and cariology. The report targets important information that will likely influence day-to-day treatment decisions. Each review is not intended to stand alone but to update interested readers so that they may visit source materials if greater detail is desired. As the profession continues its march toward evidence-based clinical decision-making, an already voluminous library of potentially valuable dental literature continues to grow. It is the intention of this review and its authors to provide assistance in navigating the extensive dental literature published in 2018. It is our hope that readers find this work useful in the clinical management of patients moving forward.