First Year Of Loading Research Articles

Peri-implantitis in patients without regular supportive therapy: Prevalence and risk indicators

ObjectivesTo determine the prevalence of peri-implant diseases in patients treated in a university setting without a regular peri-implant supportive therapy schedule, and to identify the risk indicators associated with peri-implantitis.Material and methodsA retrospective cohort study was made of patients with dental implants with at least 12 months of functional loading who did not receive regular peri-implant supportive therapy. Patient- and implant-related variables were retrieved, and clinical and radiological examinations were performed. Descriptive and bivariate analyses and multilevel logistic regression analyses were performed to identify factors associated with peri-implantitis.ResultsA total of 213 implants in 88 patients were analyzed. The patient-level prevalence of peri-implantitis and peri-implant mucositis was 26.1% (95%CI: 16.7%—35.5%) and 44.3% (95%CI: 34.0%—54.6%), respectively. Peri-implant diseases were significantly more frequent when the width of the keratinized mucosa was < 2 mm (OR = 5.26; 95%CI: 1.24—22.26; p = 0.024), and when there was 12 month post-loading bone loss (OR = 2.96; 95%CI: 1.35—6.52; p = 0.007).ConclusionsPeri-implantitis is a common finding in patients without regular peri-implant supportive therapy (prevalence 16.7–35.5%). A thin peri-implant keratinized mucosa (< 2 mm) and a higher degree of bone remodeling after loading seem to be the main risk factors for peri-implantitis in this patient profile.Clinical relevancePatients who do not engage in supportive peri-implant maintenance have a higher risk of peri-implantitis. A thin keratinized mucosa and bone loss during the first year of loading are predisposing factors for peri-implantitis.

ORTHOPEDIC REHABILITATION OF PATIENTS WITH CHRONIC GENERALIZED PERIODONTISIS USING DENTAL IMPLANTS

One of the most common methods of correcting dental defects used in modern dentistry is dental implantation. However, in conditions of periodontal pathology, planning and carrying out dental implantation causes certain difficulties. The aim of the work was to analyze the clinical effectiveness of orthopedic rehabilitation based on implants in patients with chronic periodontitis. The task of the study was to study and compare the indicators of implant stability, marginal bone tissue loss and postoperative complications in patients with chronic generalized periodontitis under the conditions of using the technique of immediate and delayed dental implantation.&#x0D; The object and methods of research. To achieve the goal, the authors formed two observation groups, in which the replacement of tooth row defects with the help of dental implants was performed in patients with generalized periodontitis of the I-II degree of severity. The first group consisted of 10 patients who underwent direct implantation and immediate functional loading. There were 10 patients in the second group, after delayed implantation, loading occurred in the generally accepted terms (2-3 months on the lower jaw and 4-5 months on the upper).&#x0D; The stability of the implants was determined using the Osstell ISQ device. A comparison of the indicators of implant stability with different implantation protocols and functional load: immediate and delayed load was carried out.&#x0D; Conclusion. The maximum value of stability of implants is registered after one year. This fact is proven in a statistically significant increase (p&lt;0.05) in the stability of the implant in both groups.X-ray evaluation of bone tissue resorption in the cervical area after the first year of loading indicates certain risks of direct implantation and immediate functional loading.&#x0D; Thus, effective prosthetics for patients with generalized periodontitis is determined by a personalized approach to each individual case, taking into account local factors and individual characteristics of the body. Most often, it is unsatisfactory oral hygiene that leads to an increase in the amount of dental deposits and creates prerequisites for the exacerbation of the inflammatory-dystrophic process in the periodontal tissues.

Experimental and numerical study of long-term behaviour of timber-timber composite (TTC) connections

Long-term sustained load (push-out) tests under an indoor uncontrolled environment were conducted on twelve specimens (in seven groups/types) of Timber-timber composite (TTC) joints with up to two identical specimens of each TTC joint type. The TTC joints were fabricated by connecting either Laminated veneer lumber (LVL) or Glued laminated timber (GLT) joists to Cross laminated timber (CLT) slab panels. Types of joists (LVL and GLT), size of coach screw shear connectors, type of shear connection (screws with or without adhesive) between the joists and CLT slab thickness and orientation (i.e., lengthwise, or crosswise) with respect to the loading direction were the main variables in the experimental program. The laboratory tests revealed that the creep coefficient after 420 days is in the range of 1.05 to 3.90 and the CLT slab orientation has minor and CLT thickness has major influence on the creep coefficient of TTC joints (for a given service load over loading capacity ratio). A creep model was calibrated against the experimental slip-time curves and the model was used to predict the creep coefficient for the 50-year design life of the structure. It was shown that more than 50% of the creep in the TTC joints occur in the first year of loading. Additionally, a 3D coupled Finite element (FE) model implemented as user defined subroutines in ABAQUS/Standard was validated against the long-term test results and accordingly input parameters for coupled long-term FE analysis of the LVL-CLT and GLT-CLT joints (with screw shear connectors) are recommend. The validated FE model was used to further confirm effect of the CLT panel thickness and orientation on the long-term slip-time and creep coefficient of the TTC joints.

Finite Beam Element for Curved Steel-Concrete Composite Box Beams Considering Time-Dependent Effect.

Curved steel–concrete composite box beams are widely used in urban overpasses and ramp bridges. In contrast to straight composite beams, curved composite box beams exhibit complex mechanical behavior with bending–torsion coupling, including constrained torsion, distortion, and interfacial biaxial slip. The shear-lag effect and curvature variation in the radial direction should be taken into account when the beam is sufficiently wide. Additionally, long-term deflection has been observed in curved composite box beams due to the shrinkage and creep effects of the concrete slab. In this paper, an equilibrium equation for a theoretical model of curved composite box beams is proposed according to the virtual work principle. The finite element method is adopted to obtain the element stiffness matrix and nodal load matrix. The age-adjusted effective modulus method is introduced to address the concrete creep effects. This 26-DOF finite beam element model is able to simulate the constrained torsion, distortion, interfacial biaxial slip, shear lag, and time-dependent effects of curved composite box beams and account for curvature variation in the radial direction. An elaborate finite element model of a typical curved composite box beam is established. The correctness and applicability of the proposed finite beam element model is verified by comparing the results from the proposed beam element model to those from the elaborate finite element model. The proposed beam element model is used to analyze the long-term behavior of curved composite box beams. The analysis shows that significant changes in the displacement, stress and shear-lag coefficient occur in the curved composite beams within the first year of loading, after which the variation tendency becomes gradual. Moreover, increases in the central angle and shear connection stiffness both reduce the change rates of displacement and stress with respect to time.

Immediate vs conventional loading of Facility-Equator system in mandibular overdenture wearers: 1-year RCT with clinical, biological, and functional evaluation.

The use of immediate loading (IML) is still poorly explored in elderly patients and implant-retained mandibular overdenture (IMO) wearers. For this reason, more comparisons to conventional loading (CL) are required. To evaluate the clinical, biological, functional, and oral health-related quality of life (OHRQOL) influence of CL and IML loading on elders wearing IMO retained by the Facility-Equator system up to 1 year after implant installation. Twenty edentulous patients received two narrow diameter implants in the mandible; the loading type (CL or IML) was randomized. The clinical parameters were monitored along with prosthetic events, marginal bone loss (MBL) and bone level change (BLC), implant stability quotients (ISQ), masticatory performance outcomes, and Interleukin 1 beta (IL-1β) and tumor necrosis factor alpha (TNF-α) levels in the peri-implant crevicular fluid during the first year of loading. The OHRQoL was assessed via the Oral Health Impact Profile-EDENT questionnaire. Data were analyzed by the Mann-Whitney, χ2 , Wilcoxon paired, and McNemar tests. After 1 year, MBL, BLC and ISQ were statistically identical (P > .05) in the CL and IML groups. The probing depth at 12 months in the CL group (2.19 mm) was higher than in the IML group (1.29 mm; P ≤ .0001). TNF-α was 33.6% higher in the CL group at 6 months (P = .043), while IL-1β was significantly higher in the IML group up to 6 months. The survival rate was 90% in the CL group and 85% in the IML group; 33 prosthetic events occurred in CL group and 23 in IML group. After 12 months, both loading protocols are viable and result in similar clinical, biological, functional, and OHRQOL outcomes. However, IML generates better adaptation of the peri-implant tissues, faster improvement in OHRQoL and fewer prosthetic intercurrences than CL.

Influence of Implant Length and Associated Parameters Upon Biomechanical Forces in Finite Element Analyses: A Systematic Review.

The aim of this systematic review is to provide an overview of finite element analyses comparing standard and short dental implants concerning biomechanical properties and to detect the most relevant parameters affecting periimplant stress concentrations. After screening the literature and assessment of studies, 36 studies were included in this review. Eighty-three percent of the studies state that short dental implants have to bear higher stress concentrations compared with standard length implants. At the same time, 44% of articles note that implant diameter can be considered a more effective design parameter than implant length to reduce stress concentrations and to avoid an overload of periimplant bone. Regardless of implant dimension, in all studies, the highest stress concentrations are found in the cortical section around the upper part of the implant. Unaffected of bone quality, implant diameter is found to play a key role to minimize periimplant stress concentrations. Concerning stress reduction implant length gains increasing relevance with decreasing bone density. Furthermore, splinting of short implants constitute an appropriate tool to avoid crestal overloading.

Peri-Implant Bone Resorption during Healing Abutment Placement: The Effect of a 0.20% Chlorhexidine Gel vs. Placebo-A Randomized Double Blind Controlled Human Study.

Introduction Peri-implant marginal bone loss (MBL) seems to be more pronounced in the first year of loading despite all the studies and changes implemented to reduce it. Among the different causes, the presence of a microgap makes the interface between fixture and abutment colonizable by bacteria, causing an inflammatory response and consequent bone resorption. To reduce this several local antiseptics like chlorhexidine digluconate (CHX) were used after surgical procedures. Aim The objective was to radiologically compare the MBL when a 0.20% CHX gel or a placebo gel was applied to the implant-abutment interface during all surgical and prosthetic phases and for a follow-up period up to 12 months. Method 32 patients (16 for each Group A and B) were enrolled and rehabilitated with a single implant (Cortex classic, Cortex, Shalomi, Israel). During each of the clinical stages a gel containing 0.20% CHX (Plak ®Gel; Polifarma Wellness Srl, Rome, Italy) or a placebo gel (Placebo, Polifarma Wellness Srl, Rome, Italy) was used as indicated by the randomization chart. In order to compare radiographic modification intraoral radiographs was taken. Also, clinical data regarding implant or prosthetic failure and gingival index were recorded. Data were presented as means and standard deviations (SD) and used for the statistical analysis. Results All implants showed no bleeding on probing and a very small plaque score at the 1 year of follow-up. MBL was statistically significantly different between the groups in every stage. Conclusion Results obtained showed that the use of CHX gel inside the connection significantly reduces MBL during the first year. A rigid disinfection protocol with 0.20% CHX from the time of implant insertion to crown delivery is recommended to reduce host inflammatory response and consequently MBL. This trial is registered with ClinicalTrials.gov Identifier: (Registration Number: NCT03431766).

Fiber-Reinforced Resin Fixed Prostheses on 4 Short Implants in Severely Atrophic Maxillas: 1-Year Results of a Prospective Cohort Study

The aim of this study was to report on 1-year outcomes of fixed full-arch fiber-reinforced resin bridges on short implants in atrophic maxillary jaws. A prospective cohort study was designed and patients with severely atrophic maxillas, corresponding to Cawood and Howell Classes V and VI, were included. Mesial and distal peri-implant bone levels were assessed on panoramic radiographs that were taken at the time of implant insertion (baseline) and during follow-up visits. Eighteen patients with 72 implants inserted in atrophic maxillary jaws were included in this study. All patients had a follow-up visit 1year after loading. The cumulative 1-year patient-based implant survival rate was 88.8%, and the cumulative 1-year implant-based survival rate was 97.2%. The marginal bone level (MBL) was -0.5±0.5mm at the time of loading (n=72) and -0.8±0.6mm (n=72) after 1year. The MBL depended substantially on the depth at the time of insertion. No prosthetic failure, such as chipping or fracture, occurred within the first year of loading. Prosthetic rehabilitation of atrophic maxillas with prostheses supported by 4 4.0-×5.0-mm or 3.0-×8.0-mm implants seems to be a viable and cost-effective treatment option in the short-term.

Implant-Abutment Connections: A Review of Biologic Consequences and Peri-implantitis Implications.

Clinicians very often have seen marginal bone loss around dental implants at the crest level early on after implant placement and uncovering. Early clinical publications had suggested that this bone loss occurred during the first year of loading. Thus, numerous attempts have been made to minimize or eliminate such bone loss. However, the timing and reason for this bone loss are not always apparent. The objective of this study was to review the evidence regarding marginal bone loss around dental implants from the standpoint of biologic consequences to help understand marginal bone changes around dental implants. One hypothesis for the bone loss around these implants was related to the presence of bacteria in the interfaces between the implant and abutment connections. The literature was reviewed regarding the three major types of implant-abutment crestal connections, including butt-joint, platform-switched, and no interface (tissue-level or one-body). This review article revealed that 1.5 to 2.0 mm of bone loss occurred around bone-level, butt-joint connections when the interface was created because the microgap was wide enough for penetration and colonization of bacteria, and that this bone loss was not observed around implants with no interface because they did not have a contaminated interface at the bone crest. Many studies have shown an advantage in the amount of marginal bone resorption for implants with a platform-switched connection, and there appears to be a significantly different biologic reaction. Recent publications indicate that such contaminated implant-abutment connections might have an effect on peri-implantitis and failure over time.

Complications During Maxillary Sinus Augmentation Associated with Interfering Septa: A New Classification of Septa

Purpose:A new classification of maxillary sinus interfering septa based on its orientation is presented along with its relationship to the prevalence and severity of sinus membrane perforations. Additionally, the impact of membrane perforation on post-operative complications and marginal bone loss during the first year of loading is evaluated.Materials & Methods:Retrospective chart review of 79 consecutive sinus lift procedures with lateral window technique and 107 implants. Preoperative Cone Beam Computed Tomography (CBCT) images were evaluated for the incidence and the direction of maxillary septa. Chart notes were examined for the incidence of membrane perforation and postoperative complications. Measurements of mesial and distal marginal bone levels and average bone resorption adjacent to each implant were calculated in intraoral radiographs taken at implant placement and during follow up appointments.Results:Interfering septa were identified in 48.1 percent of sinuses. 71.1 percent of them had the septum oriented in a buccal-lingual direction (Class I). The overall incidence of membrane perforation was 22.8 percent, and the presence of an interfering septum on CBCT scan was found to be significantly associated with the occurrence of a sinus membrane perforation (P<0.001). The mean implant marginal bone loss for sinuses, which did not experience a membrane perforation, was 0.6±0.8mm, compared with 0.9 ± 0.9 mm for the sinuses that did experience a perforation (P = 0.325).Conclusion:Septa should be identified, classified and managed with a meticulous attention to technical details. A classification based on the septal orientation is proposed since the orientation of the septa can complicate the surgical procedure and requires modification of the surgical technique.

Survival Analysis of Implant in Patients With Diabetes Mellitus: A Systematic Review.

To determine the survival trend of dental implants after functional loading for ≥1 year in diabetic patients. An electronic search of the Cochrane Oral Health Group's Trials Register, Medline and Embase, plus a manual search up to December 2015 was performed. Studies assessing the survival rate of dental implants in patients with a diagnosis of diabetes mellitus were considered eligible. Screening of studies, quality assessment, and data extraction were conducted independently by 2 reviewers. Life-table analysis and Kaplan-Meier survival curves were used to evaluate implant survival and to plot the cumulative survival rate and cumulative hazard ratio. Seven studies, including 1142 implants were identified. The cumulative survival rate was 0.96 ± 0.10 before loading, 0.93 ± 0.10 and 0.91 ± 0.10 at 1 year, and at the end of the follow-up period, respectively. The hazard ratio was 4% during the period of osseointegration, 3% during the first year of loading, and remained constant over the 6-year follow-up. Patients with diabetes mellitus showed an increasing trend of implant failure during the period of osseointegration and the first year of loading.

Narrow-diameter implants with conical connection for restoring the posterior edentulous region

BackgroundThe objective of this retrospective study was to show results from platform-switched narrow-diameter implants in the posterior edentulous region, which we followed up for more than 1 year after functional loading.MethodsNinety-eight narrow implants were inserted into 66 patients. After healing, fixed implant-supported prostheses were delivered to the patients, and Periotest and radiographic examinations were performed. After the first year of loading, the implant outcome was again evaluated clinically and radiographically using the Periotest analysis. Crestal bone loss and Periotest values (PTVs) were used to evaluate the effect of surgery, prosthesis, implant, and a host-related factor. A general linear model was used to statistically detect variables statistically associated with crestal bone loss and Periotest value.ResultsWe followed up on the implants over 1 to 4 years after loading; their survival rate was 100 %, and pronounced differences from PTVs were noted among jaw location, bone quality, and loading period. No difference was detected in bone loss among the variables studied. Bone loss after functional loading was 0.14 ± 0.39 mm. The stability value from the Periotest was −3.29 ± 0.50.ConclusionsWithin the limitations of this study, judicious use of platform-switched narrow implants with a conical connection must be considered an alternative for wide-diameter implants to restore a posterior edentulous region.

Stability and Marginal Bone Level Changes of SLActive Titanium-Zirconium Implants Placed with Flapless Surgery: A Prospective Pilot Study.

Immediately-loaded, narrow-diameter implants can be a less invasive alternative for the implant-supported fixed rehabilitation of narrow, posterior crests. To determine the stability and marginal bone level (MBL) changes of narrow-diameter, titanium-zirconium (TiZr) implants placed with flapless surgery and loaded immediately in the posterior region. Thirty-eight TiZr implants (3.3 mm diameter, 10 mm length, Roxolid, Straumann AG) were placed in the posterior crests of 14 patients with computer-guided flapless surgery as a support of 3-unit posterior bridges. Eighteen implants were loaded immediately, and 20 implants were loaded conventionally. The implant stability quotients were determined at the 1, 2, 4, and 8. weeks of healing before conventional loading, and at the 3, 6, and 12. months after loading by resonance frequency analysis. The MBL changes were measured by digital radiography. The surgical protocols were accomplished without any biological complications. There was no significant difference in the stability changes of TiZr implants between the loading groups (p > .05). The MBL changes were -0.18 ± 0.27 mm and -0.24 ± 0.27 mm at the 12. month of immediate and conventional loading, respectively, which was not statistically significant (p > .05). The stability and MBL changes of TiZr implants supporting posterior 3-unit bridges were clinically acceptable at the first year of loading.

Long-term effects of vertical bone augmentation: a systematic review.

ABSTRACTExtraction, periodontitis, or trauma can cause a reduction on the alveolar ridge. This could result in an insufficient alveolar bone width and height. Different techniques of vertical bone augmentation are described in literature. However, nowadays there is not enough evidence against lateral augmentation procedures to verify if these techniques are stable over a long period of time. Objective This review analyses the different techniques that are used to vertically augment the bone and evaluate if these techniques are stable over a long period of time.Material and Methods The MEDLINE-PubMed database was searched from its earliest records until December 22, 2014. The following search term was used: Alveolar Ridge augmentation [MESH]. Several journals were hand searched and some authors were contacted for additional information. The primary outcome measure that was analyzed was marginal bone level change around dental implants in the augmented sites, and the secondary outcomes were survival and success rates of dental implants placed in the augmented sites.Results The search yielded 203 abstracts. Ultimately, 90 articles were selected, describing 51 studies meeting the eligibility criteria. The marginal bone level change for the inlay technique and vertical guided bone regeneration are in agreement with the success criteria. Alveolar distraction showed more marginal bone level change after the first year of loading, and for the inlay technique very few studies were available.Conclusions Based on the available data in the current existing studies with a follow-up period of at least 4 to 5 years, one can summarize that there seems to be a trend that the onlay technique, alveolar distraction, and vertical guided bone regeneration are stable for at least 4 to 5 years.

Evaluation of bone remodeling around single dental implants of different lengths: a mechanobiological numerical simulation and validation using clinical data

Algorithmic models have been proposed to explain adaptive behavior of bone to loading; however, these models have not been applied to explain the biomechanics of short dental implants. Purpose of present study was to simulate bone remodeling around single implants of different lengths using mechanoregulatory tissue differentiation model derived from the Stanford theory, using finite elements analysis (FEA) and to validate the theoretical prediction with the clinical findings of crestal bone loss. Loading cycles were applied on 7-, 10-, or 13-mm-long dental implants to simulate daily mastication and bone remodeling was assessed by changes in the strain energy density of bone after a 3, 6, and 12 months of function. Moreover, clinical findings of marginal bone loss in 45 patients rehabilitated with same implant designs used in the simulation (n = 15) were computed to validate the theoretical results. FEA analysis showed that although the bone density values reduced over time in the cortical bone for all groups, bone remodeling was independent of implant length. Clinical data showed a similar pattern of bone resorption compared with the data generated from mathematical analyses, independent of implant length. The results of this study showed that the mechanoregulatory tissue model could be employed in monitoring the morphological changes in bone that is subjected to biomechanical loads. In addition, the implant length did not influence the bone remodeling around single dental implants during the first year of loading.

The alveolar ridge splitting/expansion technique: a systematic review.

The aim of this systematic review was to evaluate clinical, radiological and histological outcomes of the alveolar ridge splitting/expansion technique (ARST) with or without GBR. A screening of two databases MEDLINE (PubMed) and EMBASE (OVID) and hand search of articles were performed. Human and animal studies reporting on dental implants placed with simultaneous ARST up to May 31st 2014 were considered. Quality assessment of selected full-text articles was performed according to the ARRIVE guidelines and the Cochrane collaboration's tool to assess risk of bias. Overall, 18 human and six animal studies (risk of bias: high/unclear) were included in this review. No randomized controlled trials were found. Due to the heterogeneity of study designs, definitions of success criteria, outcome variables, observation times and surgical procedures, no meta-analysis was performed. Reported survival (18 studies) and success (nine studies) rates ranged from 91.7 to 100% and 88.2 to 100%, respectively, with a mean follow-up of 1-10 years. Crestal bone level changes (∆CBL) in some studies indicate slightly higher bone loss before and after loading. Histologic and histomorphometric data from six animal studies confirm the crestal bone loss, particularly at buccal sites. Within the limitations of this review, ARST seems to be a well-functioning one-stage alternative to extended two-stage horizontal grafting procedures. Data indicate that during healing and first year of loading, increased ∆CBL particularly at buccal sites must be anticipated. Additional horizontal GBR can help to preserve buccal bone height and width.

Radiographic Bone Level Changes of Implant-Supported Restorations in Edentulous and Partially Dentate Patients: 5-Year Results

To evaluate and compare crestal bone level changes and peri-implant status of implant-supported reconstructions in edentulous and partially dentate patients after a minimum of 5 years of loading. All patients who received a self-tapping implant with a microstructured surface during the years 2003 and 2004 at the Department of Prosthodontics, University of Bern, were included in this study. The implant restorations comprised fixed and removable prostheses for partially and completely edentulous patients. Radiographs were taken immediately after surgery, at impression making, and 1 and 5 years after loading. Crestal bone level (BIC) was measured from the implant shoulder to the first bone contact, and changes were calculated over time (ΔBIC). The associations between pocket depth, bleeding on probing (BOP), and ΔBIC were assessed. Sixty-one implants were placed in 20 patients (mean age, 62 ± 7 years). At the 5-year follow-up, 19 patients with 58 implants were available. Implant survival was 98.4% (one early failure; one patient died). The average ΔBIC between surgery and 5-year follow-up was 1.5 ± 0.9 mm and 1.1 ± 0.6 mm for edentulous and partially dentate patients, respectively. Most bone resorption (50%, 0.7 mm) occurred during the first 3 months (osseointegration) and within the first year of loading (21%, 0.3 mm). Mean annual bone loss during the 5 years of loading was < 0.12 mm. Mean pocket depth was 2.6 ± 0.7 mm. Seventeen percent of the implant sites displayed BOP; the frequency was significantly higher in women. None of the variables were significantly associated with crestal bone loss. Crestal bone loss after 5 years was within the normal range, without a significant difference between edentulous and partially dentate patients. In the short term, this implant system can be used successfully for various prosthetic indications.

The effect of marginal bone level changes on the stability of dental implants in a short-term evaluation.

To evaluate whether changes in marginal bone level (MBL) around implants, in sites with different bone types, affect the over time implant stability measured by resonance frequency analysis (RFA). Seventy-eight implants were inserted into jawbones of 32 patients using a two-stage surgical protocol, and implant bone sites were grouped according to the Lekholm and Zarb bone classification. The implant stability quotient (ISQ) was measured by RFA at four time points: implant placement, uncovering, rehabilitation, and at 1-year follow-up after loading. The MBL was measured on periapical radiographs at uncovering and at 1-year follow-up. Percent change in bone level was calculated based on the difference between the implant length and height from the crestal bone level to the implant apex. Descriptive statistics, Pearson's correlation, and repeated-measures ANOVA were used for data analysis. Significant improvement of ISQ was found between implant insertion and uncovering surgery (P<0.001), while no significant changes were detected throughout the remaining follow-up period. The greatest improvement of ISQ was observed for bone type 4, compared with the other groups (P<0.001). Percent change in bone level had no effect on longitudinal measures of ISQ (P=0.337). The ISQ difference between uncovering and 1year after loading was not correlated with percent change in bone level (r=0.16; P=0.157). There was increased implant stability after implant placement, but it was not affected by changes in marginal bone level during the first year of loading.

Loading protocols for single-implant crowns: a systematic review and meta-analysis.

To test whether or not immediate loading of single-implant crowns renders different results from early and conventional loading with respect to implant survival, marginal bone loss, stability of peri-implant soft tissue, esthetics, and patient satisfaction. An electronic search of Medline and Embase databases including studies published prior to August 1, 2012, was performed and complemented by a manual search. Randomized controlled trials (RCTs) comparing different loading protocols of single-implant crowns with a follow-up after restoration of at least 1 year were included. A meta-analysis yielded odds ratios (OR) and standardized mean differences (SMD) together with the corresponding 95% confidence intervals (95% CI). The search provided 10 RCTs comparing immediate and conventional loading and 1 RCT comparing immediate and early loading. When assessing the implant survival at 1 year of loading, the meta-analysis of 10 studies found no significant differences between immediate and conventional loading (OR = 0.75; 95% CI: 0.32 to 1.76). The total difference of marginal bone loss during the first year of function between immediate and conventional loading protocols in 7 RCTs did not reach statistical significance (SMD = -0.05 mm; 95% CI: -0.41 to 0.31 mm). There were no significant differences between immediate and conventional loading regarding implant survival and marginal bone loss at 2, 3, and 5 years of loading. Three RCTs comparing the change of papilla level between immediate and conventional loading identified no significant differences. One study investigated the recession of the buccal mucosa after implant placement and found significantly inferior soft tissue loss for immediate loading as compared to conventional loading. Two RCTs investigated the recession of the buccal mucosa after insertion of the definitive crown and found no differences between immediate and conventional loading. The esthetics and the patient satisfaction were assessed in one and two RCTs, respectively. There were no significant differences between immediate and conventional loading. Immediately and conventionally loaded single-implant crowns are equally successful regarding implant survival and marginal bone loss. This conclusion is primarily derived from studies evaluating implants inserted with a torque ≥ 20 to 45 Ncm or an implant stability quotient (ISQ) ≥ 60 to 65 and with no need for simultaneous bone augmentation. Immediately and conventionally loaded implants do not appear to differently affect the papilla height during the first year of loading. Due to the heterogeneity of the time point of baseline measurements and contradictory findings in the studies, it is difficult to draw clear conclusions regarding the recession of the buccal mucosa. With respect to the assessment of esthetic outcomes and patient satisfaction, the data available remain inconclusive.

In selected sites, short, rough-surfaced dental implants are as successful as long dental implants: A critical summary of Pommer B, Frantal S, Willer J, Posch M, Watzek G, Tepper G. Impact of dental implant length on early failure rates: a meta-analysis of observational studies. J Clin Periodontol 2011;38(9):856-863.

In adult patients, do short dental implants (< 10 millimeters) lead to failure rates similar to those for longer implants (≥ 10 mm) in the first year of loading? Two independent reviewers searched three electronic databases and 29 journals for articles published from January 1998 to January 2008. The authors included in the review only English-language, prospective observational studies in which the allocation decision occurred in the course of usual treatment. Also, implants must have been placed in nonaugmented healed jawbone after a conventional healing period of three to six months. The primary outcome measured was implant failure within the first year of prosthetic loading, determined on the basis of established criteria.1 A meta-analysis was carried out in which the authors compared the association between implant length and failure. In addition, the authors performed subgroup analyses of failure as a function of the implants’ diameter, surface texture and location in the maxillary or mandibular arch. Fifty-four trials, including 19,563 dental implants (with only a 2.4 percent dropout rate), met the inclusion criteria. The results of the meta-analysis, which consisted of 40 studies (2,223 short implants and 14,158 long implants), showed that shorter implants had an overall failure rate statistically significantly higher than that for long implants within the first year of loading (odds ratio [OR] = 1.8; 95 percent confidence interval [CI], 1.3-2.5). The results of subgroup analyses showed a statistically significant difference in failure rates for short and long implants in the maxilla, but no difference in the mandible. However, with the possible exception of the anterior maxilla, the failure rates for rough surfaced implants in the two groups (1,298 short implants and 7,544 long implants) were not statistically significantly different (OR = 1.1; 95 percent CI, 0.6-2.1). The authors found no association between implant diameter and failure rates within one year of prosthetic loading. With the possible exception of the maxillary anterior area, rough-surfaced short implants with a minimum length of 7 mm present no additional risk of failure within the first year of loading.