Use Of Short Implants Research Articles

Mathematical rationale and results of clinical use of IRIS short implants

The aim of the study was to provide a mathematical justification of the possibility of using 6.5 mm IRIS implants and to evaluate the results of orthopedic treatment in patients with partial loss of teeth. For the calculations was constructed of a composite three-dimensional computer models: the abutment screw-implant-bone. A total of 3 models were prepared: M1-implant in the spongy bone tissue, this model corresponds to the implantation on the HF when replacing one molar; M2-2 implants in the spongy bone tissue located at a distance of 4 mm connected via abutments, this model corresponds to the implantation of RF when replacing two molars; M3-implant in the cortical bone tissue, this model corresponds to the implantation of LF when replacing one molar. Loading of implants was carried out by occlusive force applied to its end surface. The results of the calculations showed that the equivalent stresses and limiting stresses of compression-tension are within the permissible values, which were obtained by us earlier in respect of the irregular implants and are consistent with the results of calculations for other systems of short implants. The clinical part of the work consisted in the treatment of 27 patients with partial loss of teeth, who had 41 iris evolution implants with a diameter of 5 mm, length of 6.5 mm after 3 years, there was a slow bone resorption in the cervical region not exceeding 0.35 mm, which corresponds to generally accepted international standards. During the first three years of operation there were no cases of loss of established implants. Thus, the data of mathematical modeling by finite element method and retrospective three-year analysis of prosthetics on IRIS evolution implants with length of 6.5 mm showed that the use of short implants in the recovery of upper and lower jaw molars is an effective method with a high success rate at long - term and resorption level of 0.34 mm.

Use of short implants or long implants with bone grafting may not result in different outcomes

Use of short implants or long implants with bone grafting may not result in different outcomes

Full-Mouth Rehabilitation with Calvarium Bone Grafts and Dental Implants for a Papillon-Lefèvre Syndrome Patient: Case Report

Papillon-Lefèvre syndrome (PLS) is a rare autosomal recessive disorder of keratinization associated with palmoplantar keratoderma and severe periodontitis resulting in complete edentulism in late adolescence. The pathognomonic dental features of PLS are pathologic migration, hypermobility, and exfoliation of the teeth without any signs of root resorption. It has been suggested that an effective way to treat PLS patients presenting early in the disease progression is extraction of the erupted primary dentition or hopeless permanent teeth followed by antibiotic coverage with periodontal therapy for the remaining teeth. Unfortunately, studies have shown that this regimen only temporarily delays the progression of periodontal disease and does not prevent further tooth loss and bone destruction in the long term. Post-tooth loss, atrophic ridges make conventional prosthodontic rehabilitation quite challenging, and more recently, implant-supported prostheses have been considered as a viable alternative. In a PLS patient, implant placement is complicated by inadequate bone volume; thus, bone augmentation techniques or the use of short implants is often considered. When large volumes of bone are required, parietal calvarium bone can be used to predictably reconstruct severe defects. A PLS patient aged 21 years presented a chief complaint of ill-fitting conventional complete dentures. The patient had severely atrophic ridges, requiring significant bone augmentation for an implant-supported prosthesis. The present case is the first example of bone augmentation using autogenous calvarium parietal graft followed by endosseous implant placement and prosthetic restoration in a PLS patient.

Short implants versus bone grafting and standard-length implants placement: a systematic review.

The aim of this study was to conduct a systematic review to compare the survival rates between short implants (length<10mm) versus standard-length implants (≥10mm) inserted in grafted bone. As secondary outcomes, marginal bone loss and survival rates of the implant supported prostheses were also analysed. Randomised controlled trials (RCT) that compared both techniques were searched on three electronic databases till June 2016, a manual search was performed on the bibliography of the collected articles, and the authors were contacted for additional references. The estimates of the interventions were expressed in relative risk (RR), mean implant survival rates and mean differences in marginal bone. Eight RCTs were included in this study. From a total of 458 short implants, 15 failed (mean survival rates=96.7%), While from 488 regular implants, 13 failed (mean survival rates=97.3%). The technique did not significantly affect: the implant failure rate (P>0.05), with RR of 1.34 (95% CI 0.67-2.87), the mean differences of marginal bone loss (P=0.18; MD -0.04mm [-0.10; 0.02] 95% CI), at loading or prosthesis failures rates (RR:0.98; 95% CI 0.40-2.41). The mean differences of marginal bone at 1year follow-up (post loading) presented significant marginal changes in the short implant group (P=0.002; MD -0.10mm [-0.16; -0.03] 95% CI) although a significant high heterogeneity was found between groups. This systematic review suggests no difference between both techniques in the treatment of atrophic arches. However, more long-term RCTs are needed to evaluate the predictability at the long run. The use of short implants might be considered an alternative treatment, since it usually requires fewer surgical phases and tends to be a more affordable option.

Evaluation of four designs of short implants placed in atrophic areas with reduced bone height: a three-year, retrospective, clinical and radiographic study

The aim of the present study was to evaluate retrospectively the clinical and radiographic behaviour of four commercially-available short implants with different macrodesigns and microdesigns in areas in which the height of the bone was reduced. We took into account the success and survival, peri-implant crestal bone loss, and the level of probing at which the gum bled. Patients were included if they had been given one or more short implants (≤8.5mm long) in the posterior jaws at least three years earlier. Three hundred and ninety-one short implants were placed in 170 subjects, and were divided in four groups based on the brand of implant. The implants were evaluated one, two, and three years after they had been inserted. Short implants had a three-year survival and success rate of 90% in all groups, and bone loss was acceptable after three years with no significant differences between them. These results support the use of short implants as an effective and safe treatment. However, within the limitations of this study, the design of the implant does seem to influence the behaviour of peri-implant bone at the crestal level.

Risk factors for single crowns supported by short (6-mm) implants in the posterior region: A prospective clinical and radiographic study.

The use of short implants is still not a consensus for challenging clinical situations, such as unfavorable crown-to-implant (C/I) ratio. This prospective study evaluated the rates of prosthetic complications and implant failure, the mean marginal bone loss of 6-mm dental implants with single crowns in posterior regions and the potential risk factors. Forty-six dental implants, 6-mm long and 4.1-mm wide, were placed in the posterior region in 20 patients. Patients were clinically and radiographically examined after the restoration with single crowns and on a yearly basis. Potential risk factors (arch, bruxism, maximum bite force, anatomical and clinical C/I ratios, and occlusal table area) were analyzed according to the following outcomes: implant survival, bone loss, and prosthetic complications. The mean follow-up time was 45 ± 9 (16-57) months. There was no early loss of implants. After prosthetic loading, 4 implants were lost (2 in the mandible and 2 in the maxilla; 91.3% survival), and there were 13 prosthetic complications (28.3%), yielding a 65.2% success rate. The frailty term showed a 95% greater chance of loss in the mandible than the maxilla. Mean peri-implant bone loss was of 0.2 ± 0.4 mm, 0.1 ± 0.2 mm, 0.1 ± 0.3 mm, and 0.2 ± 0.4 mm in the first, second, third, and fourth years, respectively, with a mean cumulative loss of 0.3 ± 0.5 mm at 48 months. In the multilevel model, the effects of the clinical C/I ratio and time were significant for bone loss (P < .001). It was estimated that a mean bone loss of 0.1 mm is associated with both a one-unit increase in time (12 months) and a 0.1 increase in the clinical C/I ratio. The other potential risk factors showed no significant relationship with the outcomes. The 6-mm implants supporting single crowns performed well, but the mandible shows a higher risk of failure. The time and clinical C/I ratio are predictors for bone loss.

The use of short implants in adolescents

The use of short implants in adolescents

Rehabilitation of a Patient with Completely Edentulous Maxillary Arch using “All on 4” Concept of Implantation

ABSTRACT Treatment options for insufficient ridge morphology includes the use of short implants, vertical ridge augmentation procedures, or cantilever prostheses in completely edentulous patients. Due to the less predictable long-term prognosis associated with the above-mentioned procedures, the “All on 4” technique was proposed for the rehabilitation in edentulous jaws. The All on 4 treatment concept meets the patient requirements with an immediately loaded fixed prosthesis supported by four implants. This article depicts a clinical report in which an “All on 4” implant treatment is done with delayed loading protocol due to inadequate primary stability obtained. How to cite this article Harshakumar K, Abraham NB, Lylajam S, Prasanth V. Rehabilitation of a Patient with Completely Edentulous Maxillary Arch using “All on 4” Concept of Implantation. Int J Prosthodont Restor Dent 2017;7(2):66-70.

Sinus Lift versus Short Implants: Results of a Prospective Radiologic Study and Critical Review of Minimally Invasive Transcrestal Sinus Lift Procedures

Introduction: The current discussion about the use of short implants to avoid bone-augmentation (“sinus lift”) in the lateral maxilla remains a controversial topic and is increasingly at odds with the reality of evolutionary biology. Aim of the study was to determine the percentage of cases from a large routine patient-sample in which short implants might be suitable to avoid sinus lift procedures. Materials and Methods: From January 2012 to June 2015, all patients in three general dental practices in Austria with at least one subantral edentulous area were subjected to routine panoramic X-ray screening. The subantral alveolar ridge heights and the mesial extension of the maxillary sinus towards the canine fossa were measured. Statistics were performed by Excel data analysis (mean value, standard deviation). Results: 2837 patients were screened with 2837 panoramic radiographs presenting 3528 edentulous subantral regions and the subantral bone heights of 5674 maxillary sinuses were surveyed. 57.43% revealed subantral alveolar ridge heights of 4 mm or less; 24.43% of all measure-points indicated a maximum alveolar ridge height of 6 mm. In 39.32% of cases, the pneumatisation of the maxillary sinuses with a subantral residual ridge height of 6 mm or less extended as far as the anatomical position of the second premolars, in 20.51% as far as the position of the first premolar and in 10.84% as far as the canine fossa. Discussion: The sinus lift procedure will continue to be one of the basic standard surgical procedures carried out by practice-based dental surgeons who perform implant surgery since in at least two thirds of the cases short implants with lengths of less than 6 mm cannot be applied. Preference should be given to sinus lift-procedures, which can be learned safely with a minimum of time-effort, least risk of failure and lowest possible level of patient morbidity. Transcrestal hydrodynamic ultrasonic sinus lift-procedures with piezotomes seem to fulfill these basic demands.

Trends in techniques to avoid bone augmentation surgery: Application of short implants, narrow-diameter implants and guided surgery.

Minimally invasive implantology using reduced implant dimensions as well as virtual treatment planning and CAD/CAM stereolithographic templates has gained popularity in recent years. The aim of the present investigation was to analyze prevailing trends in clinical utilization of these graftless therapeutic options. A total of 12.865 dental implants were placed in 5.365 patients at the Academy for Oral Implantology in Vienna, of which 5.5% were short (length<10mm), 19.5% narrow (diameter<3.75mm) and 10.6% template-guided. Application trends were analyzed using linear regression and compared between jaw location and dentition subgroups. Use of short implants and guided surgery increased significantly in all subgroups. Narrow-diameter implants were most frequent in single-tooth gaps (24.1%), however, upward trends could only be observed in partially and completely edentulous patients. Short implants were predominantly used in the mandible (9.9% vs. 2.5%, P<0.001) while guided surgery was favored in the maxilla (14.2% vs. 5.4%, P<0.001). Short implants (most frequent in partial edentulism) and guided implant surgery (most frequent in complete edentulism) represent uprising and promising surgical approaches to avoid patient morbidity associated with bone graft surgery.

Influence of Implant Length and Diameter, Bicortical Anchorage, and Sinus Augmentation on Bone Stress Distribution: Three-Dimensional Finite Element Analysis.

Clarification of the protocol for using short implants is required to enable widespread use of short implants as an available treatment option. The purpose of this study was to investigate the influences of implant length and diameter, bicortical anchorage, and sinus augmentation on peri-implant cortical bone stress by three-dimensional finite element analysis. For bone models with bone quantity A and C in the maxillary molar region, three-dimensional finite element analysis was performed using different lengths and diameters of implant computer-aided design models, and the degree of maximum principal stress distribution for each model was calculated. For bone quantity A models, the degree of stress distribution of the 4-mm-diameter, 6-mm-length implant was the greatest. For bone quantity C models, the degree of stress distribution of the 5-mm-diameter, 6-mm-length implant with bicortical anchorage was much smaller than that for the 4-mm-diameter, 13-mm-length implant with sinus augmentation. The results of this study suggest that 6-mm-length implants should be selected in cases with bone quantity C where the bone width permits increasing implant diameter from 4 mm to 5 mm.

Estudio comparativo sobre el comportamiento y la distribución de las tensiones en implantes dentales cortos e implantes dentales estándares en la región posterior del maxilar superior. Un estudio en elementos finitos

ObjectivesCurrent studies conclude that the maximum tension and the greater distribution of forces should occur around the implant neck. To compare the distribution of stress between a short dental implant osseointegrated in different available vertical bones and standard osseointegrated implants in the posterior maxilla in mixed terrain formed by the bone of the patient and Bio-Oss®. To determine the stress distribution. To study the increased diameter of the short implant. To determine whether the results support the use of short implants. Materials and methodsThe finite elements method (FEM), which helps to solve differential equations associated with a physical problem with complicated geometries, was used in this work, where the geometric region is a three-dimensional model of an implant, its crown, and a portion of the bone region of the studied area.The models were subjected to occlusion forces, 150N Angle 30° ISO 14801: 2003. The MEF software used was called Abaqus from Dasssault Systemes Enterprise. ResultsThe maximum values were concentrated in the cervical portion of the implant. Tensions in the implant are in the same range. The greater the elasticity of the elements contained in the module, the greater is the absorption of stress forces. The tension in the cortical bone showed no differences, but in the model where the diameter of the implant is increased to 4.8, a marked decrease occurs in the bone stress. The comparison of the stresses in the cancellous bone showed a difference in the stresses produced in the bone with Bio-Oss®, and it is located in the apical portion of the implant away from the area of the major stress concentration. ConclusionsThe maximum concentration of forces in cervical portion is independent of the length of the implant, being favourable to increase the diameter. It is possible to use low quality bone in for shorts implants.

Lateralization Technique and Inferior Alveolar Nerve Transposition.

Bone resorption of the posterior mandible can result in diminished bone edge and, therefore, the installation of implants in these regions becomes a challenge, especially in the presence of the mandibular canal and its contents, the inferior alveolar nerve. Several treatment alternatives are suggested: the use of short implants, guided bone regeneration, appositional bone grafting, distraction osteogenesis, inclined implants tangential to the mandibular canal, and the lateralization of the inferior alveolar nerve. The aim was to elucidate the success rate of implants in the lateralization technique and in inferior alveolar nerve transposition and to determine the most effective sensory test. We conclude that the success rate is linked to the possibility of installing implants with long bicortical anchor which favors primary stability and biomechanics.

Fixed Dental Prosthesis on 4.2 mm Length Rough Implants: A Case Series Report after an Average Loading Time of 33 Months

Aim. Several limiting factors encourage the clinician to use short implants. Among those, the presence of limiting anatomical elements and the simplification of surgical procedures are particularly significant. The goal of this study is to analyse the opportunity to extend the use of short implants to extrashort implants with a length less than 5 mm (ESI). Materials and Methods. Seven patients (3 women, 4 men; mean age 60.4 years) received extrashort implants (Straumann Implant, Palatal Orthosystem, length 4.2 mm, diameter 4.1 or 4.8 mm) in severe resorbed edentulous posterior areas. The implants were incorporated in partially fixed dentures. The osseous stability and the attachment level were recorded after a loading period of 22 to 54 months. Results. The results demonstrated a success rate of 100%, stability in the osseous level surrounding implants (mean annual mesial and distal loss of 0.026 mm and 0.105 mm, resp.), and no significant differences in the mean attachment depth between extrashort implants and contralateral teeth or implants (3.7 mm versus 3.55 mm, SD = 0.87). Splinting ESI with natural teeth resulted in significantly more bone resorption than with other implants (P=0.001). Conclusion. This exploratory study on the use of extrashort implants demonstrated good reliability over a loading period of 22 to 54 months.

Use of short implants (6 mm) in a single-tooth replacement: a 5-year follow-up prospective randomized controlled multicenter clinical study.

To evaluate prospectively clinical and radiographic outcomes of 6- or 10 mm-long implants with moderately rough surface (SLA(®) ) loaded within 7 weeks from installation and supporting single crowns in the posterior regions in the course of 5 years of loading. Sixty implants with a moderately rough surface, 30 tests (6 mm long, 4.1 mm in diameter) and 30 controls (10 mm long, 4.1 mm in diameter), were placed in posterior regions in 45 patients. After 6 weeks, impressions were taken and the implants were restored with a single fixed prosthesis made with gold-palladium alloy and porcelain. Survival rate and marginal bone loss were evaluated yearly. The clinical crown/implant ratio was calculated. During the follow-up period, five implants, four tests and one control, were lost. Of the four test implants, one was lost before loading, two between the 2nd and the 3rd years, and one during the 4th year of the follow-up period. The control implant was lost during the first year of function. Consequently, after 5 years of follow-up, a survival rate of 86.7% and 96.7% was observed at the test and control sites, respectively. The results of this study showed that 6-mm-long implants supporting single crowns loaded within 7 weeks from installation lose a small amount of marginal bone during 5 years of functional loading, similar to that of 10-mm-long implants. However, a higher degree of implant loss was recorded at the short implants, probably due to the fracturing of the surrounding bone.

Short implant in limited bone volume.

Rehabilitation of severely resorbed jaws with dental implants remains a surgical and prosthetic challenge for clinicians. The purpose of this review was to evaluate the available data on short-length implants and discuss their indications and limitations in daily clinical practice. A structured review of MEDLINE and a manual search were conducted. Thirty-two case series devoted to short-length implants, 14 reviews and 3 randomized controlled trials were identified. Of this group of papers, we can conclude that short-length implants can be successfully used to support single and multiple fixed reconstructions in posterior atrophied jaws, even in those with increased crown-to-implant ratios. The use of short-length implants allows treatment of patients who are unable to undergo complex surgical techniques for medical, anatomic or financial reasons. Moreover, the use of short-length implants in daily clinical practice reduces the need for complex surgeries, thus reducing morbidity, cost and treatment time. The use of short implants promotes the new concept of stress-minimizing surgery, allowing the surgeon to focus more on the correct three-dimensional positioning of the implant.

Long‐term retrospective evaluation of short implants in the posterior areas: clinical results after 10–12 years

To evaluate the long-term clinical results of short implants in the posterior areas and analyse the possible influence of different variables on implant success rate and marginal bone loss (MBL). A retrospective study design was used. Patients were included if they had received one or more short implants (≤8.5 mm long) in the posterior jaws at least 10 years earlier. All implants were embedded in plasma rich in growth factors (PRGF). The cumulative success rate was the primary outcome. MBL and the influence of different variables as secondary outcomes were assessed. A total of 111 short implants (7.0, 7.5 and 8.5 mm in length) placed in 75 patients met the inclusion criteria. Of which, 94 were splinted to longer ones. The mean follow-up was 123.3 months (SD = 10.4 months). The mean crown-implant ratio was 1.4 (SD = 0.3). The mean MBL was 1.0 mm at mesial (SD = 0.7) and 0.9 mm (SD = 0.6) at distal aspect. One short implant failed. Success rate was 98.9% and 98.2% for the implant and patient-based analysis respectively. No relationship was observed between the studied variables and the MBL. These clinical results support the use of short implants as an effective and safe long-term treatment option.

The effect of shape, length and diameter of implants on primary stability based on resonance frequency analysis.

The aim of this in vitro study was to evaluate the effect of shape, diameter and length of implants on their primary stability based on resonance frequency analysis. Replace select tapered and Branemark MK III implants were selected. Each of these two selected groups was divided into nine subgroups based on the implant length (IL) (short, medium and long) and the implant diameter (ID) (narrow platform [NP], regular platform [RP] and wide platform [WP]). Five implants were assigned to each of the nine subgroups. Implants were placed in artificial bone blocks with bone quality similar to D3 bone. Immediately after the implant placement, its primary stability was measured using Osstell Mentor equipment. T-test and Tukey's honest significant difference Post hoc were performed for data analysis. Statistical significance was defined at P < 0.05. Replace select system showed significantly higher primary stability compared to the Branemark system, when using the short implants for all three diameters (P ≤ 0.004). However, in medium length implants there were no significant differences between the two implant systems (P ≥ 0.31). In long implants, only when the NP and RP implants were used, the Replace Select system showed significantly higher primary stability compared to the Branemark system (P = 0.000). In the replace select system, long implants had a significantly higher primary stability compared to medium and short length implants (P ≤ 0.003). In the NP and RP Branemark implants, short implants showed significantly lower primary stability compared to medium and long implants (P ≤ 0.002). However, in WP Branemark implants, primary stability increased significantly with increasing the IL from short to medium and from medium to long (P = 0.000). There were also significant differences between NP and the two other wider implants in both systems (P = 0.000). The use of tapered implants is recommended, especially, when the use of short implants is necessary. The use of RP implants is also preferred to WP implants, because thicker bone wall will remain in place when applying RP implants. Furthermore, no significant difference was observed between RP and WP implants.

A three-dimensional finite element analysis of the stress distribution on morse taper implants surface

PurposeThis finite element analysis (FEA) compared stress distribution on external surface of different morse taper implants, varying implant bodies length and dimensions of metal-ceramic crowns in order to maintain the occlusal alignment. MethodsThree-dimensional finite element (FE) models were designed representing a posterior left side segment of the mandible: group 0, 3 implants of 11mm length; group 1, implants of 13mm, 11mm and 5mm length; group 2, 1 implant of 11mm and 2 implants of 5mm length; group 3, 3 implants of 5mm length. The abutments heights were 3.5mm for 13mm and 11mm implants (regular) and 0.8mm for 5mm implants (short). Evaluation was performed on a computer program (Ansys software), with oblique loads of 365N for molars and 200N for premolars, applied on ridges of cusps and grooves. ResultsAbutments with 0.8mm height generated less von Mises stresses compared with 3.5mm height. The use of short implants associated with bigger crowns concentrated higher stress distribution and stress values on the surface implants, principally on the vestibular side (oblique direction of the loads). The more distal implant concentrated higher stress. ConclusionsMoreover, these 5mm implants were positioned at the cortical bone level, which has higher elastic modulus and may have influenced at the stress distribution. However, despite the higher stresses, these implants were well able to withstand the applied forces.

Long-Term Outcomes for the Treatment of Atrophic Posterior Maxilla: A Systematic Review of Literature

The aim of the present systematic review was to estimate the implant survival rate in different types of techniques for the rehabilitation of posterior atrophic maxilla, after at least 3 years of follow-up. MEDLINE database was searched using a combination of specific terms. A hand searching of the relevant journals and of the reference lists of systematic reviews was also performed. All retrospective and prospective studies evaluating short implants in posterior maxilla, osteotome sinus floor elevation and lateral approach sinus floor elevation, and having a follow-up of at least 3 years, were included. Forty-four articles were included in the review. In four studies reporting on a total of 901 short implants, the implant survival rate varied from 86.5% to 98.2% with up to 5 years follow-up. For the osteotome technique, 1,208 implants in eight studies were considered, showing a survival rate varying from 95.4% to 100% after 3-year follow-up. Twenty-nine studies, accounting for 6,940 implants placed in 2,707 sinuses augmented through lateral technique were considered. Implant survival rate varied from 75.57% to 100%. Only three comparative studies were found that showed no significant difference in clinical outcomes between lateral approach and osteotome technique. Sinus floor elevation with the lateral approach and with the osteotome technique is an effective and well-documented therapeutic option for the rehabilitation of atrophic posterior maxilla. The use of short implants is promising but needs further investigation to be considered as effective as the other techniques in the long term. However, the indication for the three different techniques is not perfectly equivalent and the treatment choice should be based on a careful evaluation of the individual case, in particular on the available residual bone.