Short Implants Research Articles

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

To answer the question: What do we know so far about the clinical performance of short implants (≤ 7mm) 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? An overview of SRs was conducted. The searches were performed in six electronic databases and grey literature. SRs about short (≤ 7mm) 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. 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. In an overall low-to-very low confidence levels, short implants appear to perform better in the mid-term (up to 5years) 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. Short implants could represent a viable, simpler, and less invasive treatment when available bone height is limited.

Comparison of periprosthetic bone mineral density between two types of short-stems in total hip arthroplasty with a mean follow-up of 4 years

IntroductionThe use of short stems in primary hip arthroplasty has grown considerably in recent years, with a large variety of designs and stabilization methods available. Few studies have directly compared how these designs and fixation modes influence the bone mineral density (BMD) that is said to be better preserved with shorter implants. This led us to carry out a medium-term retrospective comparative study to (1) specify how the design of two different types of short stems influences the periprosthetic BMD, (2) compare the radiological and clinical outcomes of these stems. HypothesisThe periprosthetic BMD of a short stem varies based on the implant's design. Materials and methodsNinety-three patients underwent total hip arthroplasty (THA) with a short stem between July 2012 and July 2014. Two groups of patients were formed: Vitae™ short stem (Adler Ortho, Milan, France), Optimys™ short stem (Mathys, Bettlach, Switzerland). The Vitae group consisted of 46 patients, while the Optimys group consisted of 47 patients. The mean age was 66 years, and the mean body mass index (BMI) was 26 kg/m2. The groups had comparable age, BMI, sex, Harris Hip score and preoperative radiological features. Periprosthetic BMD of the two types of implants was determined between the 1st and 4th year postoperative using dual-energy x-ray absorptiometry (DEXA) in the Gruen zones. The radiological and clinical outcomes were also determined. ResultsThere was a significant decrease in BMD in zone 7(−5.8%±0.1 CI95%[−0.09; −0.02] (p=0.003)), zone 2 (−4.8% ±0.1 CI95%[−0.093; −0.003] (p=0.038)) and zone 6 (−11% ±0.2 CI95%[−0.19; −0.03] (p=0.009)) in the patients with Vitae stems and in zone 2 (−13.7%±0.3 CI95%[−0.25; −0.03] (p=0.018)) in the patients with Optimys stems. A significant difference in BMD in zone 7 at 1 year (p=0.014) and 4 years (p=0.001) postoperative and in zone 6 (p=0.011) at 4 years postoperative existed between groups, with the Optimys group having higher BMD. There was a significant increase in femoral offset in the Optimys group but not the Vitae group: Δoffset=–0.50 mm±5.2 CI95%[−2.05; 1.05] (p=0.522) and Δoffset=2.79 mm±4.2 CI95%[1.21; 4.37] (p=0.001). The Harris Hip score was not significantly different between the two groups at 4 years postoperative (95.3±2.5 [88; 99] vs. 95.2±2.6 [88; 99] (p=0.991)). DiscussionThe design of short stems appears to influence the distribution of loads and the periprosthetic BMD. These stems are associated with very good radiological and clinical results in the medium term. Bone remodeling appears to continue beyond 1 year after the THA procedure. Level of evidenceIII; Retrospective case-control study.

Influence of osteoporosis and mechanical loading on bone around osseointegrated dental implants: A rodent study

This study aimed to evaluate the influence of estrogen deficiency and mechanical loading on bone around osseointegrated dental implants in a rat jaw model. The maxillary right first molars of 36 rats were extracted. One week later, the rats were divided into an unloaded group and a loaded group; short head implants and long head implants were inserted respectively. Nine weeks after implantation, the rats were further subjected to ovariectomy (OVX) or sham surgery. All animals were euthanized 21 weeks after OVX. Micro-computed tomography, histological and histomorphometrical evaluation were undertaken. Systemic bone mineral density and bone volume fraction decreased in OVX groups compared with the sham controls. Histomorphometrical observation indicated that unloaded OVX group showed significantly damaged osseointegration and bone loss versus the loaded OVX group. Both the bone density (BD) inside the peri-implant grooves and the percentage of bone-to-implant contact (BIC) were lower in the OVX groups than in the sham-surgery groups, although mechanical loading increased the BIC and BD in the loaded OVX group compared with the unloaded OVX group. An increased number of positive cells for tartrate-resistant acid phosphatase was observed in the OVX groups versus the sham controls. The percentage of sclerostin-positive osteocytes was lower under loaded compared with unloaded conditions in both the OVX groups and the sham controls. In conclusion, estrogen deficiency could be a risk factor for the long-term stability of osseointegrated implants, while mechanical loading could attenuate the negative influence of estrogen deficiency on bone formation and osseointegration.

Dynamic navigation and technical improvements in zygomatic surgery

The rehabilitation of the severely atrophied edentulous maxilla poses a great challenge to surgeons and prosthodontics that work on this particular area. The classic approach implies bone augmentation techniques by means of bone grafting, bone distraction techniques, tilted and short implants. All of these require major surgery, sometimes associated with morbidity at donor and receptor sites and functional rehabilitation of the patient must occur in two surgical stages. Since the development of the zygomatic implants by Per-Ingvar Branemark, there’s an alternative to bone grafting techniques, using the body of the zygomatic bone as major point of anchorage to an intraoral osteointegrated implant. This procedure allows the patient to regain orofacial function in only one surgical stage, with high predictability, less morbidity, time spend and costs. In this scientific article the authors present a set of technical improvements in the zygomatic implant (S.I.N. - Implant System, São Paulo, Brazil) in combination with a new dynamic navigation system called StealthStation™ (Medtronic, Dublin, Irland) used for the first time in this type of surgery.

Short Versus Regular-Length Implants to Rehabilitate Partially Edentulous Mandible: A 2-Year Prospective Split-Mouth Clinical Study.

Many studies have evaluated short implants (SIs); however, it is still unclear whether SIs are reliable and can be used to simplify surgical and prosthetic protocols with successful clinical outcomes. The aim of this nonrandom, conveniently sampled, prospective, split-mouth study was to compare the clinical outcomes when short SI (≤8 mm) or regular-length implants (RIs; >10 mm) were used in the posterior mandible 2 years after the delivery of splinted reconstructions. Each participant (N = 10) received 4 implants in the posterior mandible; 2 SIs were placed on one side, and 2 RIs were placed contralaterally. Implants were restored with splinted, screw-retained, porcelain-fused-to-metal reconstructions. Survival and success rates, peri-implant marginal bone level (MBL), and soft-tissue parameters were evaluated. No participant dropouts were recorded. Both types of implants showed 100% success and survival rates. From prosthetic delivery to 24 months postloading, bone remineralization of +0.40 mm for the SIs and +0.36 mm for the RIs was observed without statistically significant differences in MBL between the implant types (P = .993). SIs showed significantly higher (P = .001) clinical attachment level and probing depth values. Chipping occurred in one situation in the RI group, resulting in a 97.5% prosthetic success rate, which was 100% for the SIs. After 2 years, SIs with splinted reconstructions showed comparable clinical outcomes to those of RIs. Further long-term controlled clinical studies with balanced experimental designs evaluating random and larger populations are required to corroborate these findings.

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

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

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

BackgroundThe 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.ResultsBoth 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.ConclusionWithin 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 registrationClinicaltrials.Gov ID: NCT04518020. Date of registration: August 14, 2020, retrospectively registered.

Survival Rates of Splinted and Nonsplinted Prostheses Supported by Short Dental Implants (≤8.5 mm): A Systematic Review and Meta-Analysis.

To evaluate and compare the implant survival rates, marginal bone loss, and mechanical complications of prostheses supported by splinted and nonsplinted short implants (≤8.5 mm). Electronic database (MEDLINE, CENTRAL, Web of Science, and EMBASE) and manual searches up to May 2021 were conducted to identify studies comparing splinted and nonsplinted short implants (≤8.5 mm). The primary outcome was implant survival rate. Secondary outcomes were marginal bone loss and mechanical complications. The quality of included studies and risk-of-bias were assessed according to the Newcastle-Ottawa Scale. A random-effects model was used to analyze the data. Twelve studies fulfilled the inclusion criteria and featured 1506 short implants (596 nonsplinted and 910 splinted) with a follow-up time ranging from 1 to 16 years. Quantitative analysis found no statistically significant differences between splinted and nonsplinted short implants (≤8.5 mm) for survival rate (RR= 0.98; 95% CI 0.96, 1.01; p = 0.26)) and marginal bone loss (SMD = -0.08; 95% CI- 0.23, 0.07; p = 0.28). Veneer chipping, abutment screw breakage, screw loosening, and loss of retention were reported in the selected studies as common complications. However, no statistically significant difference was found between splinted and nonsplinted short implants (RR = 0.56; 95% CI 0.20, 1.54; p = 0.26). Within the limitations of the present meta-analysis, it might be concluded that splinted short implants (≤8.5 mm) do not present superior performance in survival rate, marginal bone maintenance and prevention of mechanical complications compared with single-unit prostheses.

Clinical, radiographic and restorative parameters for short tuberosity implants placed in smokers: a retrospective study with 5year follow-up.

This study aimed to estimate and compare the clinical, radiographic, and restorative parameters around short tuberosity implants (STIs) placed in cigarette smokers (CS) and never smokers (NS). In this 60-month follow-up retrospective study, a total of 50 (37 males + 13 females) individuals who had received 82 dental implants were included. These participants were categorized into two groups as follows: (i) Group-1: 25 self-reported systemically healthy CS with 43 STIs; and (ii) Group-2: 25 self-reported systemically healthy NS with 39 STIs. In both groups, peri-implant plaque index (PI), probing depth (PD), bleeding on probing (BOP), and crestal bone loss (CBL) and restorative parameters were measured at 12 and 60months of follow-up. Group comparisons were performed utilizing the Kruskal-Wallis test. The significance level was set at p < 0.05. In CS and NS, the mean age of participants was 58.5 and 60.7years, respectively. No statistically significant differences were observed in the overall mean levels of PD and CBL around STIs among CS and NS. However, a statistically significant increase was observed in the mean scores of BOP and PI around STIs in the NS and CS at 12 and 60months follow-up, respectively. In both groups, the loosening of the implant was the most frequently encountered type of STI failure. The outcomes of the present study suggest that STIs placed in maxillary tuberosity can show reliable clinical, radiographic, and restorative stability among cigarettes smokers and non-smokers. However, the role of smoking status and oral hygiene cannot be disregarded in this scenario.

SHORT IMPLANTS- AN EVOLVING TREND- A REVIEW

Short implants have been proposed as one of the positive treatment options for compromised edentulous regions. Decreased bone height, poor bone quality often limit the use of conventional implants and usually necessitate complex surgical procedures like sinus lift or bone augmentations which are associated with increased morbidity, treatment time and cost. Though the crown root ratio of short implants is controversial, they have demonstrated a high success rate with innovations that have bolstered its effectiveness through the modifications in micro and macro surface topography, surgical bone drilling protocols and implant diameter. Photo functionalization of implants and customized implants using 3D printing are some of the promising developments in short implants. KEYWORDS: Short Implants, Implant surface topography, Bone grafting, Photo functionalization, Customized Implants

Short Dental Implants: State of the Art and Systematic Review

&#x0D; Introduction: The success of dental implants is due to their ability to osseointegrate, with direct contact of the implant surface with the bone, without the interposition of fibrous tissue. Because many patients do not receive implant treatments because they do not have adequate or sufficient bone height, the development of shorter implants could meet the needs of these patients. Objective: To carry out a brief systematic review to present the state of the art of using short implants. Methods: The present study followed a concise systematic review model. The search was carried out in the PubMed, Embase, Ovid, Cochrane Library, Web Of Science, and Scopus databases. The quality of the studies was based on the GRADE instrument and the risk of bias was analyzed according to the Cochrane instrument. Results: Short implants are an increasingly common alternative to other surgical techniques in areas where bone availability is reduced. Despite the advantages they offer, a variety of biological repercussions have been described in the literature that can even lead to their loss. Conclusion: The studies analyzed showed that short implants are a reliable, safe, and practical alternative to be used in situations with reduced bone height. They do not present bone loss or resorption over the years, nor the risk of fracture or any damage to patients, as long as they have an adequate design, correct technique, and meticulous planning.&#x0D;

Zygomatic Implant: State of the Art

&#x0D; Introduction: In the dental implant scenario, the rehabilitation of the maxilla severely reabsorbed with endosseous implants remains a challenge. There are less aggressive alternatives, including short implants, inclined implants, and especially zygomatic (ZI) implants. In cases where the height and width of the residual bone do not allow the placement of conventional dental implants, the ZI can be considered. Objective: Conducted a concise systematic review to analyze the main literary findings on the use of the zygomatic implant as an important alternative for a dental implant, to present the state of the art to the dental community. Methods: The present study followed a concise systematic review model. The search was carried out in the PubMed, Embase, Ovid, Cochrane Library, Web Of Science, and Scopus databases. The quality of the studies was based on the GRADE instrument and the risk of bias was analyzed according to the Cochrane instrument. Results and Conclusion: Zygomatic implants appear to be a consolidated therapeutic option for significantly atrophic maxilla, offering a promising alternative to costly heavy bone graft techniques, fewer complications, less time for rehabilitation, less required prosthodontic work, and significantly higher survival rates. Thus, the zygomatic implant is revolutionizing the implant procedure in the posterior atrophic maxilla, eliminating the complications of bone augmentation and sinus elevation, with delayed healing, showing better clinical results compared to the bone graft, pointing to a possible gold standard for a dental implant.&#x0D;

Failure Risk of Short Dental Implants Under Immediate Loading: A Meta-Analysis.

Currently, there is no clear clinical evidence that short implants are suitable for immediate loading. Therefore, this meta-analysis aims to evaluate whether immediate loading increases the failure risk of short dental implants. This meta-analysis was registered at PROSPERO (CRD 42020195890). PubMed, Embase, and Cochrane Library databases were searched to collect all clinical studies comparing the failure rates of short dental implants (<10 mm) and standard implants (≥10 mm) under the condition of immediate loading and studies comparing the failure rates of short dental implants under immediate loading versus early or delayed loading. All of the clinical studies with available relevant data were eligible for inclusion. The Cochrane Risk of Bias tool was adopted to evaluate the risk of bias for the randomized controlled trial (RCT), while Newcastle-Ottawa Quality Assessment Scale (NOS) was used for the observational studies (OS). The OR value of each included study and its 95% CI were pooled to estimate the failure risk of short dental implants under immediate loading. The heterogeneity among studies was evaluated through Cochran's Q test and I2 . Seventeen studies, 5 RCTs and 12 OS studies, with a total of 2461 dental implants were analyzed. Four of the RCT studies were of low risk of bias and one was of unclear risk, while all of the OS studies were of moderate or high quality. Compared with standard implants, short implants did not have an increased failure risk under immediate loading (OR: 1.38, 95% CI: 0.67-2.84, p = 0.997, fixed model). In addition, the OR value of implant failure for short implants under immediate loading compared to that for short implants under early or delayed loading was 1.22 (95% CI: 0.33-4.55, p = 0.104, random model), which was also not significantly different. There is not enough evidence to show that short dental implants under immediate loading may have higher implant failure risk compared to standard implants under immediate loading and short implants under early or delayed loading. Therefore, an immediate loading protocol may not increase the failure risk of short dental implants.

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

BackgroundOsseodensification (OD) has shown to improve implant stability; however, the influences of implant design, dimensions, and surgical site characteristics are unknown.PurposeTo compare the insertion torque (IT) and temporal implant stability quotients (ISQ) of implants placed via OD or subtractive drilling (SD).Materials and MethodsThis 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.ResultsData 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.ConclusionsOD 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.

Tilted versus Short Implants Supporting Mandibular Fixed Detachable Prosthesis (In vitro study)

Purpose: This study aimed to evaluate strain induced in implants supporting fixed detachable prosthesis with different implant protocols using strain gauge analysis. Material and methods: This stress analysis study used two 3D models simulating a completely edentulous lower arch to support and retain fixed detachable prostheses. In the first model four implant beds were considered; two anterior implants oriented axially and two posterior implants placed at the premolar region tilted 30 degrees. In the second model implant beds were designed with two anterior implants oriented axially and two short posterior implants 8 mm length placed in the first molar region oriented axially. Standardized static load was applied unilaterally by using a loading device (universal-testing machine). Strain gauge was used to measure strains induced in each implant. Results: Regarding the loaded side: Strain induced in the anterior implant and in the lingual and distal aspect of the posterior implant in the first model has shown higher strains compared to the second model. This difference was statistically insignificant in the anterior implant and in the lingual aspect of the posterior implant, while strains induced in the distal aspect of the posterior implant was statistically significant higher in the first model compared to the second model. Conclusion: With the limitation of this in vitro study, it can be concluded that short implants induce less stresses distally than tilted implants.

A 3D finite element analysis of bone tissue in three-unit implant-supported prostheses configurations through varying configuration factors (single-unit and splinted crowns in straight-line and offset configurations) and implant lengths in the maxillary posterior region

The objective of the present study was to analyze the stress and microstrain on cortical bone tissue caused by occlusal forces on three-unit implant-supported prostheses placed in the maxillary posterior region through varying configuration factors and implant lengths using 3D finite element analysis. Fifteen three-dimensional models were simulated with the support of the In Vesalius, SolidWorks 2016, and Rhinoceros 4.0 software programs. Each three-dimensional model included a maxillary bone block corresponding to the region from the 1st premolar to the 1st right molar with three EH implants measuring 4.0 mm in diameter, which supported the three-unit metal-ceramic screw-retained prosthesis through varying configuration factors (single-unit and splinted crowns: straight-line and tripod design) and implant lengths (10, 8.5, and 7 mm × Ø4 mm). The FEMAP 11.4.2 program was used to generate the finite element models in the pre- and post-processing phases. Bone tissue was analyzed using Maximum Principal Stress (MPa) and Microstrain (με) maps. The highest stress/microstrain values were observed in oblique loading. In addition, splinting associated with the offset configuration generated improved biomechanical behavior. Furthermore, the association of short implants with longer implants did not exhibit any biomechanical benefits. Moreover, a reduced implant length (i.e., 7 mm) generated unfavorable biomechanical behavior. Splinting was effective in reducing the stress/microstrain on cortical bone tissue, especially when associated with the offset configuration of the implants. Also, an increased implant length decreased the stress/microstrain in the bone tissue, and splinted short implants presented similar biomechanical behavior to short implants associated with longer implants.

Mandibular bone height changes in two different design concepts of four implant assisted overdenture

Purpose: This comparative study was conducted to compare between two different design concepts of four implant assisted complete mandibular overdenture regarding the residual alveolar bone height changes.Materials and Methods: Ten healthy completely edentulous male patients were selected for this study. For each patient, a conventional complete denture was constructed. Each mandibular denture was duplicated to be used as a radiographic stent, then the CBCT surgical guide template was printed according to each design concept of 4-implant overdenture. The CBCT surgical guide templates were used for installing the implants according to flapless surgical technique followed by delayed loading. According to the two design concepts of the 4-implant overdenture used in this study, the patients were randomly classified into two equal groups: group [A]had two vertical canine implants with two axial 1st molar short implants (short design concept), and group [B]had two vertical canine implants with two distally inclined premolar implants (inclined design concept). Radiographic evaluations were performed immediately (T0), 6 months (T6), and 12 months (T12) respectively after picking up of the ball attachments.

مقایسه ی میزان جوش خوردگی در بیماران با شکستگی اینترتروکانتریک با گاما نیل کوتاه قفل و غیر قفل؛ یک مطالعه مقطعی

Introduction: Intertrochanteric fractures, which are one type of hip fracture, have been considered as a major public health issue in many nations. This study was carried out with the aim of comparing the rate of fusion between patients with intertrochanteric fractures treated with short sliding and non-sliding Gamma nail implants. Methods: This is a retrospective cross-sectional study performed in 2018 and 2019, and 47 patients with intertrochanteric fractures, who referred to Imam Hussein Hospital, and were treated using either sliding or non-sliding gamma nail implants were compared. The rates of bone fusion, fused union, and bone repairments were all assessed using radiography 1, 3, 7 and 12 months after the operation. Results: In the current survey, 68.6% of cases were treated with non-sliding gamma nail implants, while 31.4% were treated with sliding gamma nail implants. The mean period of bone fusion was 4.5 months in patients with non-sliding gamma nail implants and 5.5 months in patients with sliding gamma nail implants. In patients treated with sliding gamma nail implants, treatment of 28.5% of patients failed, and in the group of patients treated with non-sliding gamma nail, treatment failure was reported in 12.5% of patients. In addition, mean postoperative Harris Hip Score (HHS) in the group treated with non-sliding gamma nail implants was significantly higher than the group treated with sliding gamma nail implants (P = 0.002). Conclusion: Based on the findings of the present study, it seems that treatment with short non-sliding gamma nail implants is a better method compared to treatment with sliding gamma nail implants.

Synthetic Putty and Simultaneous Short Implant Placement in Crestal Sinus Lifting Procedures: 13–36 Months Follow-Up: A Case Series

Introduction: Aim of this investigation is to show that in sites with less than 4 mm of bone height of the sinus floor, synthetic putty bone graft and simultaneous short implant placement in crestal sinus lifting procedures result in sufficient bone gain, and is a valuable option to the more invasive lateral-window approach. Case presentation: Four patients missing a single tooth or more in the posterior maxilla with remaining alveolar ridge height of less than 4mm underwent crestal sinus lift procedures with bone grafting using a synthetic putty material simultaneously. Loading of the short implants was done with a minimum of 4 months after placement showing bone growth around the implant and lift of the Schneiderian membrane between 2.3mm-7.3mm. Conclusion: Crestal sinus lift, in combination with a short implant and a synthetic putty bone graft, is a good alternative for lateral more invasive sinus lift when the thickness of the sinus floor is less than 4mm.