Survival Of Dental Implants Research Articles

The Effect of Crown-to-Implant Ratio on the Clinical Outcomes of Dental Implants: A Systematic Review.

To analyze the effect of crown-to-implant (C/I) ratio over survival rate, marginal bone loss, and prosthetic complications of dental implants. Electronic (PubMed, Ovid MEDLINE, and Cochrane Central) and manual searches for clinical trials with a minimum follow-up of 1 year were performed. Clinical and anatomical C/I ratios were obtained. Regression models were created to assess for potential correlation between C/I ratio (anatomical and clinical) and survival rate, marginal bone loss, or prosthetic complications. A subgroup analysis of 6-mm implants and a comparison of C/I ratios of > 1.5 versus ≤ 1.5 were also performed. The Newcastle-Ottawa Scale and Cochrane Risk of Bias Tool For Randomized Controlled Trials were used to evaluate the risk of bias. An overall moderate risk of bias was assessed among the selected articles. Linear regression analysis did not reveal a significant correlation between anatomical C/I ratios and survival rate (P = .905), marginal bone loss (P = 0.33), or prosthetic complications (P = .67). Similarly, no significant correlation to survival rate and marginal bone loss (P = 0.42, P = 0.84) was observed in the articles providing the clinical C/I ratios. Increased C/I ratio does not seem to be directly related with increased marginal bone loss and does not represent a biomechanical risk factor for the stability of the prosthesis and for the survival of dental implants.

A Literature Review Study on Atomic Ions Dissolution of Titanium and Its Alloys in Implant Dentistry.

This review of literature paper was done in order to conduct a review of the literature and an assessment of the effects of titanium implant corrosion on peri-implant health and success in the oral environment. This paper evaluates and critically reviews the findings of the multiple in-depth in vivo and in vitro studies that are related to corrosion aspects of the titanium and its alloys. A literature survey was conducted by electronic search in Medline and studies that were published between 1940 and August 2018 were selected. The search terms used were types of corrosion, corrosion of titanium implants, titanium corrosion, metal ion release from the titanium implants, fretting and pitting corrosion, implant corrosion, peri implantitis, and corrosion. Both in vivo and in vitro studies were also included in the review. The search and selection resulted in 64 articles. These articles were divided on the basis of their context to different kinds of corrosion related to titanium dental implants. It is evident that metal ions are released from titanium and titanium alloy dental implants as a result of corrosion. Corrosion of implants is multifactorial, including electrical, chemical, and mechanical factors, which have an effect on the peri-implant tissues and microbiota. The literature surveyed showed that corrosion related to titanium and its alloys has an effect on the health of peri-implant soft and hard tissue and the long term survival of metal dental implants. It can be concluded that presence of the long-term corrosion reaction along with continuous corrosion leads to the release of ions into the peri-implant tissue but also to a disintegration of the implant that contribute to material fatigue and even fracture of the abutments and implant body or both. This combined impact of the corrosion, bacterial activity, chemical reactions, and functional stresses are to be looked at as important factors of implant failure. The findings can be used to explore the possible strategies of research to investigate the biological impact of implant materials.

Survival of Titanium-Zirconium and Titanium Dental Implants in Cigarette-smokers and Never-smokers: A 5-Year Follow-up.

To compare the peri-implant clinical and radiographic status around bone-level narrow-diameter titanium-zirconium (TiZr) implants and titanium (Ti) implants placed in cigarette-smokers (CS) and never-smokers (NS). Partially edentulous CS and NS rehabilitated with TiZr and Ti implants were included. Demographic data and information regarding smoking habits were collected. Participants were divided into four groups: group-1, CS with TiZr implants; group-2, NS with TiZr implants; group-3, CS with Ti implants; and group-4, NS with Ti implants. 36, 30, 31 and 33 implants were placed in 24, 23, 24 and 25 male individuals in groups 1, 2, 3 and 4, respectively. Peri-implant plaque index (PI), bleeding on probing (BOP), probing depth (PD) and mesial and distal crestal bone loss (CBL) were measured. All patients were enrolled in biannual routine oral prophylaxis care at least until the fifth year of follow-up and oral hygiene instructions were reinforced at each recall appointment. P < 0.05 was considered statistically significant. At the 3- and 5-year follow-ups, there was no statistically significant difference in the peri-implant PI, BOP, PD and CBL between individuals in all groups. In all groups, the implant success and survival rates were 100% and 100%, respectively, at the 5-year follow-up. The TiZr and Ti dental implants can remain clinically and radiographically stable in CS in a manner similar to NS. Routine oral hygiene maintenance plays an essential role in this regard.

Treatment of maxillary molar with furcation involvement - Case report

Purposes: The aim of this clinical report is to discuss the advantages and the steps of the root separation and resection approach in a maxillary molar with a class III furcation of the palatine root with a follow-up of 24 months. Case report: A patient with tooth mobility and bleeding after probing, was diagnosed with a Chronic Periodontitis Generalized Moderate and Localized Severe. Hygienic phase with oral hygiene instructions, scaling and root planning was performed. Due to class III furcation of the palatine root of the teeth 16 and some remaining pockets deepths, was decided to execute an apical repositioning flap on the 1st sextant among with the palatine root amputation combined with the endodontic treatment. During the surgical procedure, it was also performed a reduction of the palate thickness from teeth 15 to 17; in distal area of the 17 a distal wedged was performed in order to remove all the pockets. After the surgery, the patient was inserted in a long-lasting individualized supportive periodontal treatment.This case has a follow up of 24 months. Conclusions: Similar survival rates are described in the literature when we compared the root amputation with the dental implants survival rate, but the first one is cheaper and allows to keep the natural tooth. We can’t forget that the periodontitis is a risk factor of peri-implantitis. This clinical case shows that, with a high motivated patient and with the complete periodontal treatment, is possible to obtain excellent results with root separation and resection in maxillary molars class III.

Survival of Dental Implants Replacing Previously Failed Implants: A Retrospective Study in a University Setting.

The rate of dental implant failures ranges from 3% to 8%, with that number increasing as the number of implants placed increases. When an implant fails, the survival rate drops significantly when a second or third attempt is performed. The aim of this study was to evaluate the survival rate of an implant placed in a previously failed implant site and to explore the risk factors that might affect the outcome of the second procedure. A retrospective chart review was conducted for patients receiving dental implants at the University of Texas, School of Dentistry from 1985 to 2017. Exclusion criteria included patients with genetic diseases, radiation and chemotherapy, or an age less than 18 years. Data on age, sex, race, tobacco use, diabetes, cardiovascular, osteoporosis, implant brand, anatomical location of the implant, implant length and width, respective information on the replacement implant, and professional maintenance were collected for analysis. A total of 1,234 patients with 2,742 implants were included. A chart review found that of the 247 failed implants, replacement of implants was performed in 85 patients with 99 implants. More than half of the initial implants failed within the first year of placement. Based on the 12-month performance of each brand, the initially failed implants were categorized as high, medium, or low survival rates. Based on this categorization, the replacement implants that belonged to the medium survival rate category showed higher survival rates than the high survival group of the initially failed implants. The cumulative survival rates of the replacement implants were 91% at 1 year, 88% at 5 years, and 83% at 10 years. Implant failures were more common prior to functional loading.

Dental implants - are they better than natural teeth?

Nowadays, patients find much information on dental treatment from the Internet. There is a vast amount of information on dental implants, in contrast to the limited information available on natural teeth. This review addresses research on survival of natural teeth and dental implants, and discusses factors affecting the survival rate of implants, as well as certain dogmas in implant dentistry. To simplify treatment planning, the article presents a classification system in which teeth are classified as secure, doubtful, or irrational to treat. Secure teeth should last for a long period of time without need for complex treatment. Doubtful teeth are teeth that might need complicated treatment and additional maintenance in order to be maintained. Teeth irrational to treat are teeth that cannot be saved and for which extraction is the only treatment option. Multiple risk factors might decrease the survival probability of teeth. The survival and success rates of dental implants will never succeed the survival rates of healthy, clean teeth. Dental implants and implant-supported restorations are an excellent treatment modality, but it must always be kept in mind that it is associated with a risk of biological and technical complications. Implants are supposed to replace missing teeth - they are not supposed to replace teeth.

Long-Term Survival of Dental Implants in Irradiated Head and Neck Cancer Patients: A Retrospective Analysis

Objective: To analyze the long-term survival of dental implants in patients previously treated with radiotherapy.

Obesity and dental implant treatment: a review

Aim Success of dental implants depends mainly on osseointegration between bone and titanium surface. Since osseointegration relies on balanced bone turnover, it can be assumed that any conditions that interfere with homeostasis of bone modelling/remodeling might be detrimental to survival of dental implants. Obesity has become a serious public health problem, and has been shown to be closely linked to a wide array of pathophysiologic consequences, including insulin resistance or pre-diabetes. Obese-insulin resistance or pre-diabetic condition is characterized by hyperinsulinemia with euglycemia. The impacts of type 2 diabetes mellitus (T2DM) on the success of dental implants and the factors to improve osseointegration in diabetic condition have been thoroughly investigated. Much evidence demonstrated that T2DM impaired the bone healing around dental implants, possibly due to hyperglycemic condition. However, the effect of obese-insulin resistant condition or pre-diabetes on survival of dental implants has not been investigated. This review aims to summarize the current findings of effect of obesity toward bone health and osseointegration of dental implants.Conclusion The studies favor the relatively negative impact of diabetes on osseointegration, but more scientific studies are necessary.

Survival of dental implants placed in vascularised fibula free flaps after jaw reconstruction

PurposeAblative oncological surgery to treat head-and-neck cancer often triggers a requirement for jaw reconstruction. Modern surgical procedures using free microvascular flaps afford acceptable outcomes in terms of restoration of bony and soft tissue defects. A fibula free flap is often the preferred flap, as the bone length is considerable and a two-surgeon approach is possible. Dental implants play important roles in functional rehabilitation. Our aim was to evaluate the survival of dental implants placed in reconstructed areas after transfer of fibula tissue to the jaw. Materials and methodsWe retrospectively studied 34 patients who underwent ablative tumour surgery and jaw reconstruction using osteocutaneous fibula free flaps and who then received dental implants. We evaluated implant survival and success, survival of the fibula flap, and clinical and radiographic data. ResultsWe included 34 patients, 23 of whom were diagnosed with squamous cell carcinoma. In total, 134 dental implants were inserted in transferred fibula bone. The cumulative implant survival rate was 81%. The survival rate of the 34 fibula flaps transplanted after surgical reconstruction was 97%. ConclusionThe insertion of endosseous implants after jaw reconstruction using vascularised fibula tissue yields successful dental rehabilitation in patients with oral cancers.

The Effect of Moderately Controlled Type 2 Diabetes on Dental Implant Survival and Peri-implant Bone Loss: A Long-Term Retrospective Study.

The objective of this study was to assess whether long-term implant survival rates and bone loss in patients with moderately controlled type 2 diabetes is similar to the rates reported in the nondiabetic population. This retrospective observational study utilized patient medical records from a general practitioner's dental office. The records of patients who had moderately controlled type 2 diabetes with hemoglobin A1C (HbA1c) up to 8% and glucose level below 150 mg/dL were reviewed, as patients with HbA1c up to 7% are considered to be well-controlled type 2 diabetes. Follow-up data were recorded and analyzed. Inclusion criteria were as follows: partially edentulous patients with missing teeth who were subsequently treated with implant-supported prosthetic restorations; patients were at least 18 years of age and demonstrated the ability to maintain oral hygiene. Exclusion criteria were as follows: patients did not present for annual follow-up visits; patients presented with a neglected periodontal status; patient records had incomplete surgical or restorative data or nondiagnostic radiographs; implants with external hexagonal and machined surfaces. All the restorations were cement-retained. Three different implant insertion/placement methods were used: (1) implants immediately inserted following tooth extraction; (2) implants inserted 6 to 8 weeks after tooth extraction to allow for primary healing; and (3) implants inserted 4 to 6 months after tooth extraction. After review of more than 3,256 medical records, 169 patients were identified (with 1,112 implants) who met the inclusion criteria. The mean follow-up time was 8.7 years, with a minimum of 4.9 years. Sixty-seven implants failed, yielding a 94% overall implant survival rate. The overall mean bone loss around the implants was 1.98 (± 1.81) mm. Comparable to data published earlier, no statistical significance in survival rate was found between the nondiabetic and diabetic population. The delayed insertion protocol presented the least bone loss, compared with immediate insertion (P = .06), and compared with early insertion (P = .046). The results show that implant survival and bone loss levels were comparable to reported outcomes in the nondiabetic population. The delayed insertion protocol presented less bone loss compared with other insertion methods. Likewise, less bone loss was found in implants placed in the posterior region.

Impact of surgical management in cases of intraoperative membrane perforation during a sinus lift procedure: a follow-up on bone graft stability and implant success

BackgroundUntil now, sinus floor elevation represents the gold standard procedure in the atrophic maxilla in order to facilitate dental implant insertion. Although the procedure remains highly predictive, the perforation of the Schneiderian membrane might compromise the stability of the augmented bone and implant success due to chronic sinus infection. The aim of this retrospective cohort study was to show that a membrane tear, if detected and surgically properly addressed, has no influence on the survival of dental implants and bone resorption in the augmented area.MethodsThirty-one patients with 39 perforations could be included in this evaluation, and a control group of 32 patients with 40 sinus lift procedures without complications were compared regarding the radiographically determined development of bone level, peri-implant infection, and implant loss.ResultsImplant survival was 98.9% in the perforation group over an observation period of 2.7 (± 2.03) years compared to 100% in the control group after 1.8 (± 1.57) years. The residual bone level was significantly lower in the perforation group (p = 0.05) but showed no difference direct postoperatively (p = 0.7851) or in the follow-up assessment (p = 0.2338). Bone resorption remained not different between both groups (p = 0.945). A two-stage procedure was more frequent in the perforation group (p = 0.0003) as well as peri-implantitis (p = 0.0004).ConclusionsWithin the limits of our study, the perforation of the Schneiderian membrane did not have a negative impact on long-term graft stability or the overall implant survival.

Impact of Chronic Kidney Disease Mineral and Bone Disorder on Jaw and Alveolar Bone Metabolism: A Narrative Review.

Chronic kidney disease (CKD) has become a worldwide public health problem. It is estimated that nearly 90% of patients with chronic renal failure manifest some symptoms of oral disease. With advances in medical treatment, CKD patients are living longer and require oral care. Chronic kidney disease is often accompanied by disturbances in mineral metabolism which are classified as their own clinical entity known as CKD-mineral and bone disorder (CKD-MBD). CKD-MBD affects all aspects of bone physiology: bone volume, bone turnover and bone mineralization. Jaw bones affected with CKD-MBD can have important clinical implications for the survival and osseointegration of dental implants, success of bone regeneration therapy, and increased risk of bone loss in patients with periodontitis or risk of bone fracture. Assessment of bone turnover is the most important diagnostic tool to monitor progression of CKD-MBD. Bone biomarkers and radiographical examination of bone density may be particularly useful to both, diagnosis and monitoring of bone turnover. Cone beam computed tomography (CBCT) as a reliable method with many advantages over other radiographic methods can be used for analysis of jaw bone micro-architectural changes and may be of a great help in bone quality determination in CKD-MBD.

Single Sitting Surgical Treatment of Generalized Aggressive Periodontitis Using GTR Technique and Immediate Implant Placement with 10-Year Follow-Up

This case report exhibits a patient with generalized aggressive periodontitis who has been under maintenance for the past 12 years after being surgically treated in a single sitting and restored with dental implants. A 41-year-old systemically healthy male patient presented complaining of lower anterior teeth mobility and pain in the upper right quadrant. After clinical and radiographic examination, the upper right molars and lower anterior incisors were deemed unrestorable. Covered by doxycycline, the patient received a nonsurgical periodontal treatment. Three weeks later, teeth extraction, immediate implant placement, immediate nonloading provisional prosthesis, and a guided tissue regeneration were performed at indicated areas in a single sitting. The clinical decisions were based on patient compliance, the status of the existing periodontal tissues, and the prognosis of the remaining teeth. During the 12-year follow-up period, no residual pockets were observed and there was no exacerbation of the inflammatory condition. Marginal bone stability is present on all implants. For aggressive periodontal disease, a high risk of relapse as well as limited success and survival of dental implants should be considered. This case shows proper containment of the disease based on appropriate treatment planning and a strict maintenance program.

Long-Term Effects of Bone Morphogenetic Protein-2-Loaded Calcium Phosphate on Maxillary Sinus Lift Surgery for Delayed and Simultaneous Dental Implantation.

Maxillary sinus lift surgery (MSLS) is considered to be a useful treatment method for patients with atrophic alveolar bone. Choosing a suitable surgical procedure to simultaneously decrease graft absorption and obtain long-term survival of dental implants is still a challenge. In this study, 20 patients received MSLS with graft of bone morphogenetic protein 2 (BMP2)-loaded calcium phosphate. Dental implants were placed simultaneously in 10 patients receiving MSLS (1-stage group), and in 10 patients receiving dental implants with a 3 to 6 months delay (2-stage group). The effects were evaluated based on clinical and radiographic examination during a 4 to 5 years follow-up. The results showed that only 1 perforation of the maxillary sinus mucosa was observed in 1-stage group, and was patched with a collagen membrane. An average bone gain of 6.8 mm was observed, and all implants exhibited no looseness, peri-implantitis, or fracture, all of which were stable during the follow-up and exhibited nice dental function during a 4 to 5 years follow-up. The loss of peri-implant bone height was 1.12 ± 0.47 and 1.10 ± 0.39 mm, the probing depth of periodontal pocket was 1.79 ± 0.62 and 1.81 ± 0.71 mm, the sulcular bleeding index was 1.63 ± 0.47 and 1.72 ± 0.54 in 1-stage group and 2-stage group, respectively, and no significant differences existed between these 2 groups. These findings implied that BMP2-loaded calcium phosphate may be a suitable material for MSLS, especially for patients with minimal bone height. Clinicians can use the 1- or 2-stage technique based on clinical condition, patients' choice and clinicians' experience. In patients where implants cannot be stabilized for patients with minimal bone height, 2-stage surgery may be more suitable.

Consistency of Dental Hygiene Therapy Utilizing Various Dental Hygiene Instrumentation and Its Effect on Peri-implant Health and Survival of Dental Implants: A Retrospective Study.

The purpose of this retrospective study was to provide practice-based evidence to determine if the consistency of dental hygiene therapy, despite utilizing instrumentation literature that has proven to cause alterations to implant surfaces, affects peri-implant health or survival. The study sample comprised patients with implant-supported full-arch fixed dental prostheses who were distributed into two groups. The consistent hygiene group patients had dental hygiene therapy at a minimum biannually and were exposed to at least three dental hygiene instrument materials. The inconsistent hygiene group patients had dental hygiene therapy at a minimum once every 3 to 10 years and were exposed to at least three dental hygiene instrument materials. Years of survival free of soft tissue pathology and/or implant failure were estimated. Continuous features were summarized with medians, interquartile ranges (IQRs), and ranges; categorical features were summarized with frequency counts and percentages. Among 48 patients in the consistent hygiene group, 11 patients experienced soft tissue pathology or implant failure at a median of 11.3 years; among 99 patients in the inconsistent hygiene group, 17 patients experienced soft tissue pathology or implant failure at a median of 4.8 years. The survival free of soft tissue pathology or implant failure rate at 5 years was 94% for the consistent hygiene group and 91% for the inconsistent hygiene group. The survival free of soft tissue pathology or implant failure rate at 20 years was 70% for the consistent hygiene group and 79% for the inconsistent hygiene group (P = .91). Although no statistical differences were found between the groups, this practice-based evidence suggests more consistent dental hygiene therapy increases the median in years in which soft tissue pathology or implant failure is present.

Survival and Complications of Single Dental Implants in the Edentulous Mandible Following Immediate or Delayed Loading: A Randomized Controlled Clinical Trial

It was the aim of this 24-mo randomized controlled clinical trial to investigate whether the survival of a single median implant placed in the edentulous mandible to retain a complete denture is not compromised by immediate loading. Secondary outcomes were differences in prosthetic complications between the loading principles. Each of the 158 patients who received an implant was randomly assigned to the immediate loading group (n = 81) or the delayed loading group (n = 77). Recall visits were performed 1 mo after implant placement (for only the delayed loading group) and 1, 4, 12, and 24 mo after implant loading. Nine implants failed in the immediate loading group, all within the first 3 mo of implant loading, and 1 implant failed in the delayed loading group prior to loading. Noninferiority of implant survival of the immediate loading group, as compared with the delayed loading group, could not be shown (P = 0.81). Consistent with this result, a secondary analysis with Fisher exact test revealed that the observed difference in implant survival between the treatment groups was indeed statistically significant (P = 0.019). The most frequent prosthetic complications and maintenance interventions in the mandible were retention adjustments, denture fractures, pressure sores, and matrix exchanges. There was only 1 statistically significant difference between the groups regarding the parameter “fracture of the denture base in the ball attachment area” (P = 0.007). The results indicate that immediate loading of a single implant in the edentulous mandible reveals inferior survival than that of delayed loading and therefore should be considered only in exceptional cases (German Clinical Trials Register: DRKS00003730).

The impact of glucocorticosteroids administered for systemic diseases on the osseointegration and survival of dental implants placed without bone grafting—A retrospective study in 31 patients

PurposeTo evaluate the impact of glucocorticosteroids, administered for the treatment of systemic diseases, on the osseointegration and survival of dental implants placed without bone grafting. Materials and methodsA retrospective study was conducted in search of patients treated with dental implants while receiving glucocorticosteroid therapy for various systemic diseases. In these cases, a conventional two-stage surgical protocol was used, without bone regeneration procedures. The osseointegration was clinically and radiographically tested at the uncovering of the implants. The follow-up after loading was set at a minimum of 3 years. ResultsA total of 31 patients were included in the study. Of the 105 dental implants placed, 104 were osseointegrated (99%). No bone absorption was radiographically noted at the uncovering of the osseointegrated implants. All of the osseointegrated implants were successfully loaded for the prosthetic restoration. The mean follow-up period after loading was 71 months, with an implant survival rate of 99%. ConclusionsGlucocorticosteroid intake for systemic diseases does not have a significant impact on the osseointegration and the 3-year survival of dental implants placed with a conventional two-stage surgical protocol and without bone grafting. Therefore, it should not be considered a contraindication for dental implant placement.

Epidemiology of Implant Mortality Disparity Among Intraoral Positions and Prosthesis Types.

To examine the disparity of single-crown implant failure with a similar loss of the splinted prosthesis in differing anatomical locations while controlling for other demographic and clinical variables that may confound the relationship between prosthesis types and implant loss. A multicenter retrospective cohort study was designed to include patients treated with dental implants from 2003 to 2014. The variables included age, sex, systemic disease, bone graft, implant placement date, position of dental implant, length of dental implant, diameter of dental implant, loading time, type of prosthesis, type of opposing occlusion, latest check date, and survival or loss of the dental implant. The demographic and clinical variables' influence on the survival of dental implants was estimated by the Kaplan-Meier method. The position and diameter were adjusted for the accurate estimation of the relationship between the prosthesis type and survival of the dental implant with the Cox proportional hazard method. A total of 1,151 dental implants from 403 patients were ascertained. After adjusting for the confounding effect of position and diameter, single-crown prostheses were 38.1 (95% CI: 15.1-118) times more likely to be lost than the connected-type prostheses. For single-crown implants, the waiting time for osseointegration before loading was the highest for the maxillary molar position and the lowest for the mandibular molar position (P < .0001), while the most frequent implant loss occurred in the maxillary anterior area, and the second frequent area was the maxillary molar position; the lowest occurrence of implant loss was for the mandibular molar position. This disparity was statistically significant (P = .0271). Despite the high survival rates of endosseous implants as a whole, since the variation of implant loss was observed among the different anatomical positions for single-crown implants, special attention has to be given to the maxillary anterior and maxillary molar positions. A longer healing time assuming compensation for disadvantageous bone quality was not directly effective in increasing implant longevity in the vulnerable positions.

Implant Survival in One-Stage Lateral versus Crestal Sinus Lift Procedures - A Systematic Review and Meta-Analysis

Objectives: The aim of this systematic review was to study the survival of dental implants placed in posterior maxilla with 4-8 mm residual bone height using one-stage lateral versus crestal sinus lifting approaches Methods/Statistical Analysis: Three electronic databases and hand searching were performed up to February 2016 for studies, comparing lateral versus crestal sinus lifting approaches. The scientific terms: “Crestal approach”, “Lateral approach”, “Internal Sinus Lift”, “External Sinus Lift”, “Sinus Floor Augmentation” and “Dental Implants” were used. Initially, title and abstract screening was performed for the retrieved articles followed by a full-text evaluation. Meta-analysis for implant survival was performed using RevMan 5.1 software. Findings: Screening of 1321 papers resulted in four eligible articles. The included retrospective cohort studies showed high risk whereas in RCT, the risk of bias was low. Meta-analysis revealed no differences in implant survival [RR = 1.01 (95% CI: 0.98-1.05)] between both approaches. Application/Improvements: The less invasive crestal approach can successfully replace the one-stage lateral approach in patients with 4-8 mm residual bone height.

Fracture strength and probability of survival of narrow and extra-narrow dental implants after fatigue testing: In vitro and in silico analysis

PurposeTo assess the probability of survival (reliability) and failure modes of narrow implants with different diameters. Materials and methodsFor fatigue testing, 42 implants with the same macrogeometry and internal conical connection were divided, according to diameter, as follows: narrow (Ø3.3×10mm) and extra-narrow (Ø2.9×10mm) (21 per group). Identical abutments were torqued to the implants and standardized maxillary incisor crowns were cemented and subjected to step-stress accelerated life testing (SSALT) in water. The use-level probability Weibull curves, and reliability for a mission of 50,000 and 100,000 cycles at 50N, 100, 150 and 180N were calculated. For the finite element analysis (FEA), two virtual models, simulating the samples tested in fatigue, were constructed. Loading at 50N and 100N were applied 30° off-axis at the crown. The von-Mises stress was calculated for implant and abutment. ResultsThe beta (β) values were: 0.67 for narrow and 1.32 for extra-narrow implants, indicating that failure rates did not increase with fatigue in the former, but more likely were associated with damage accumulation and wear-out failures in the latter. Both groups showed high reliability (up to 97.5%) at 50 and 100N. A decreased reliability was observed for both groups at 150 and 180N (ranging from 0 to 82.3%), but no significant difference was observed between groups. Failure predominantly involved abutment fracture for both groups. FEA at 50N-load, Ø3.3mm showed higher von-Mises stress for abutment (7.75%) and implant (2%) when compared to the Ø2.9mm. ConclusionsThere was no significant difference between narrow and extra-narrow implants regarding probability of survival. The failure mode was similar for both groups, restricted to abutment fracture.