Sandblasted And Acid-etched Implants Research Articles

Biomechanical Investigation of the Osseointegration of Titanium Implants With Different Surfaces Placed With Allogeneic Bone Transfer.

Allogeneic grafts can be preferred to autogenous grafts in plastic and oral-maxillofacial surgery for vertical and horizontal bone deficiencies. Implant surface properties are an important factor in osseointegration. This study aims to evaluate the osseointegration levels of titanium implants with machined, sand-blasted, and acid-etched (SLA) and resorbable blast material (RBM) surfaces placed together with allogeneic bone tissue transplantations obtained from the tibia bone using biomechanical method. Twenty-five female Sprague-Dawley rats were included in the study. The rats were divided into groups in which machined (n=7), SLA (n=7), and RBM (n=7) surface implants were placed with the transplantation of bone taken from the tibia. Four rats (both left and right tibias) were used as donors. Grafts and implants were surgically placed in the corticocancellous part of the metaphyseal area of the tibia bones of rats. At the end of the 4-week experimental setup, all rats were killed, and the implants and surrounding bone tissue were subjected to biomechanical reverse torque analysis (N/cm). Sand-blasted acid-etched surface implants were observed to have higher biomechanical osseointegration levels than RBM and machined surface implants (P<0.05). No statistical difference could be detected between the RBM and machined surface implants (P>0.05). On the basis of the limited results of this study, it can be concluded that the osseointegration levels of SLA surface implants placed with allogeneic bone transplantation may be better than those of machined and RBM surface implants.

Comparison of marginal bone loss in SLA and RBM implants: A prospective cohort study.

The study aims to answer the following question: Among the patients who received a dental implant, is there any difference in marginal bone loss (MBL) between sandblasted and acid-etched (SLA) and resorbable blast media (RBM) implants? The study aimed to evaluate marginal bone loss in SLA and RBM implants one year after loading. A Prospective Cohort Study. In this prospective cohort study with a pre-protocol population, subjects were assigned into two groups: Subjects received SLA implants in group 1 and RBM in group 2. MBL was assessed 12 months after loadings through digital parallel radiographs. An Independent t-test was used to compare MBL between the two groups. Sixty-six implants were studied (each group 33 implants). The mean of MBL in the RBM group was significantly higher than the SLA group (1.39 ± 0.31 mm, 0.89 ± 0.26 mm, respectively, P < 0.001). MBL in the mesial sides of implants in the RBM group was significantly higher than the SLA group (1.28 ± 0.29 mm, 0.8 ± 0.29 mm, respectively, P < 0.001). Analysis of the data demonstrated a significantly higher mean of MBL in the distal sides of implants in the RBM group than in the SLA group (1.51 ± 0.35 mm, 0.97 ± 0.27 mm, respectively, P < 0.001). In both groups, the mean of MBL on the distal side was significantly higher than on the mesial side (P < 0.05). Within this study's limitation, RBM implants showed significantly more MBL than SLA implants.

Does Biphasic Calcium Phosphate-Coated Surface Increase the Secondary Stability in Dental Implants? A Split-Mouth Study.

This study aimed to evaluate biphasic calcium phosphate coating (BCPC) on the secondary stability of dental implants compared to sand-blasted and acid-etched (SLA) implants. This is a split-mouth study. Thirty subjects (20 males and ten females) underwent a dental implant procedure to replace mandibular first or second molars bilaterally. The subjects were randomly assigned to BCPC or SLA groups. The resonance frequency analysis measurements were performed two, four, six, and eight weeks after the implant placement. Sixty implants were placed in the two groups (30 implants per group). The mean ISQ was 52.26 ± 3.73 in group 1 and 50.21 ± 2.59 in group 2 on day 14 after the implant insertion, 63.20 ± 2.76 in group 1 and 58.80 ± 2.14 in group 2 on day 28, 72.30 ± 3.15 in group 1 and 64.53 ± 3.19 in group 2 on day 42, and 78.70 ± 1.56 in group 1 and 71.63 ± 3.22 in group 2 on day 56. The data analysis demonstrated significant differences between the two groups in terms of the mean ISQ at various evaluation times. Regarding ISQ measurements, the secondary stability in BCPC implants may be higher compared to SLA implants in two months after implant insertion.

Evaluation of the three methods of bacterial decontamination on implants with three different surfaces.

The main goal of the treatment of the peri-implantitis is to decontaminate the surface of the implant, thereby enabling further treatment involving, e.g., guided bone regeneration. Since new implants of the rougher surface were introduced to the common dental practice, decontamination is even more difficult. The aim of the study was to evaluate 3 different methods of decontaminating implants with 3 different surfaces. A total of 30 dental implants with 3 different surface types (machined, sandblasted, and acid-etched (SLA) and hydroxyapatite (HA)-coated) were used in the study. Each group of implants was coated with Escherichia coli biofilm and cultivated. Afterwards, the implants were transferred to the jaw model and treated with a different method: sonic scaler mechanical debridement with a Woodpecker PT5 sonic scaler (1st group), and mechanical debridement with sonic scaler and with the combination with chemical agent Perisolv® (2nd group), and with Er:YAG laser treatment (3rd group). Each implant was treated with the specific method and sent for further microbiological evaluation. The highest level of decontamination was achieved for machined-surface implants and the lowest for HA-coated implants. The method with the highest biofilm reduction was the scaler and Perisolv® group. The highest level of decontamination of HA-coated implants were achieved for Er:YAG laser irradiation method. In the following paper, the superiority of combined chemical-mechanical method of decontaminating the surface of the implant on SLA and machined-surface implants was proved. On the contrary, Er:YAG laser irradiation was reported as the best option for decontamination of the HA-coated implants. In our opinion, it is a significant finding, revealing that the method of peri-implantitis management should be considered in accordance to the type of the surface of the implant (customized to the surface of the implant).

Do the New Hydrophilic Surface Have Any Influence on Early Success Rate and Implant Stability during Osseointegration Period? Four-Month Preliminary Results from a Split-Mouth, Randomized Controlled Trial.

Objective The objective of this study is to compare the implant stability of Hiossen ET III implants with its new hydrophilic (NH) surface and Hiossen ET III implants with the sandblasted and acid-etched (SA) surface. Materials and Methods Patients required at least two teeth to be rehabilitated with a fixed, implant-supported restoration, consecutively enrolled. Patients randomly received SA surface implants (SA group) or SA implants with a newly developed bioabsorbable apatite nanocoating (NH group). Outcome measures were implant and prosthetic survival rate, complications, insertion torque, and implant stability quotient (ISQ) measured at implant placement and every week up to 8 weeks after implant placement. Comparison between groups was made by unpaired t -test, while the comparison between each follow-up will be made by paired t -tests to detect any change during the follow-up. Complications and failures were compared using Fisher's exact test. Results A total of 14 patients were treated with 28 implants (14 SA and 14 NH). No implant and prosthesis failed 4 months after implant placement. No complications were experienced. At the 2nd week after implants placement, two implants in the SA group showed discontinuous measurements versus none in the NH group ( p = 0.4815). Implants unscrewed during ISQ measurements and were rescrewed. Data recording stopped for 6 weeks. Both implants osseointegrated without any further complication. The NH implants did not show physiological ISQ decrease between 2nd and 4th week after implant placement, showing a more even pattern of ISQ values compared with SA implants (77.1 ± 4.6 vs. 72.9 ± 11.5; difference: 4.2 ± 12.1; p = 0.258). High ISQ values were found in both groups at each time point. Conclusions NH implants are a viable alternative to SA surface, as they seem to avoid the ISQ drop during the remodeling phase.

The Influence of Type 2 Diabetes Mellitus on the Osseointegration of Titanium Implants With Different Surface Modifications-A Histomorphometric Study in High-Fat Diet/Low-Dose Streptozotocin-Treated Rats.

Type 2 diabetes mellitus (T2DM) is a systemic disease that also compromises the bone healing capacity. In healthy individuals, surface modifications of dental implants are proven to increase bone response and implant success. The aim of this study was to clarify if the surface modifications also improve osseointegration in a setting with diabetes mellitus. T2DM was induced in 7 rats by a high-fat diet/low-dose streptozotocin injection. All animals received a hydroxyapatite (HA) implant, a sandblasted and acid-etched (SLA) implant, and a standard machined titanium implant for control in the tibia. After 4 weeks, thin-ground sections were produced, and the volume of new bone formation (nBV/TV) and bone-to-implant contact (nB.I/Im.I) were histomorphometrically analyzed. Both surface modifications led to an increase of osseointegration compared with the machined surface implant in rats with T2DM. nBV/TV was highest in the SLA implants, whereas nB.I/Im.I was highest in the HA group. Regardless of the surface modification, a superordinate regional pattern of new bone formation over the length of the implant was observed. Implants with HA coating and SLA surface modifications seem to have the potential to increase osseointegration also in T2DM rats when compared with a conventional machined surface.

Effect of Plasma Oxidation-Treated TiOx Film on Early Osseointegration.

To develop a TiOx film with high wettability using plasma oxidation methodology and to evaluate the effect of such surface modification on new bone formation and early osseointegration. Twenty sandblasted and acid-etched (SLA) titanium implants layered with a TiOx film layer were modified by plasma oxidation using a Radio Frequency Plasma Enhanced Chemical Vapor Deposition (RFPECVD) system. Twenty SLA implants without any treatment were employed as the control group. Scanning electron microscopy was used to evaluate surface morphology of the coating. X-ray photoelectron spectroscopy (XPS) was utilized to identify the chemical composition of the implant surface, and the wettability was tested with the help of the contact angle calculation. All implants were randomly inserted into the proximal tibia of 20 rats with a split-plot design. Four weeks after implantation, early osseointegration of the two groups was analyzed by a removal torque test and histologic analysis. The surface characteristics showed that both SLA and plasma oxidization-treated SLA (PO-SLA) surfaces displayed similar typical isotropic irregular indentations. As revealed by the XPS analyses, both TiO2 and Ti2O3 were coexistent in the PO-SLA surface. The contact angle measurement revealed that the super-hydrophilic surface was created out in the PO-SLA surface. Four weeks after implantation, a higher removal torque value was observed in the group of implants with the PO-SLA surface compared with the control group (12.68 ± 1.07 vs 9.95 ± 1.42 Ncm, P < .05), and a higher rate of bone-to-implant contact was also detected in the same group of implants with the PO-SLA surface (47.79% ± 9.59% vs 39.41% ± 9.00%, P < .05). The bone area ratio was also higher in the PO-SLA surface group than the control group (39.10% ± 10.01% vs 29.01% ± 7.24%, P < .05). It was indicated that the PO-SLA surface has combined the effect of high wettability and micro/nano-structures to notably increase early bone apposition.

Coating of Sandblasted and Acid-Etched Dental Implants With Tantalum Using Vacuum Plasma Spraying.

The objective was to prepare tantalum (Ta)-coated sandblasted and acid-etched (SLA) dental implants using vacuum plasma spraying (VPS) and to analyze their morphologies. Twelve SLA implants were coated with Ta using VPS. The topographies of the coatings and Ta/SLA surface interfaces were examined using scanning electron microscopy. The thickness at 4 locations for 6 Ta-coated and 6 uncoated SLA implants and pore sizes of the neck, central, and root areas of Ta-coated implants were measured. SPSS v20.0 was used for statistical analysis. The Ta coatings were rough and consisted of pitted structures with various pore sizes; no cracks were observed. The Ta/SLA surface interface was tightly bonded. The 95% confidence interval of the Ta coating thickness was (114.0759, 129.3574). The maximal pore diameter was concentrated at 200 to 400 nm. SLA dental implants were successfully coated with Ta using VPS. The nanoporous structure of these implants may facilitate osseointegration compared with uncoated SLA implants.

The effect of strontium-loaded rough titanium surface on early osseointegration.

It is not clear whether surface bioactive chemistry plays an important role in the early osseointegration of micro-structured titanium implants that have the same surface topography at the micrometer and submicrometer scales. In this study, magnetron sputtering methodology was employed for the preparation of Sr coating on sandblasted and acid-etched (SLA) titanium implant without changing the surface characteristics. The study of the surface morphology of the coating was carried out with the use of scanning electron microscopy, and the chemical composition of the surface was examined by X-ray energy-dispersive spectrometry. Twenty SLA implants together with 20 Sr-SLA implants were randomly inserted into the proximal tibia of 20 rats. The early osseointegration of the Sr-SLA implant was compared with SLA implant by removal torque test and histological analysis following two and eight weeks of implantation, correspondingly. As revealed by the surface characteristics, both Sr-SLA and SLA surfaces exhibited similar typical isotropic irregular indentations. The strontium ions were effectively incorporated into the SLA surface (the atomic ratio is 2%). Following two and eight weeks of healing, significant increases in removal torque values ( p < 0.05) were taken into observation in respect of Sr-SLA implant. Histologically, the Sr-SLA implants displayed significantly higher bone-to-implant contact percentages and bone area ratio in comparison with the SLA implant at eight weeks ( p < 0.05). At two weeks, the bone-implant contact percentages, together with bone area ratio of Sr-SLA surface appeared to be a little bit slightly greater than that of SLA surface. But the statistical difference was not significant. These results indicated that the chemical modification with Sr incorporated by magnetron sputtering treatment in moderately rough surfaced implants remarkably increases early bone apposition.

Surgical treatment of peri-implantitis intrabony lesions by means of deproteinized bovine bone mineral with 10% collagen: 7-year-results.

The aim of this study was to evaluate the long-term results of the surgical treatment of single peri-implantitis intrabony defects, by means of deproteinized bovine bone mineral with 10% collagen (DBBMC). The original population consisted of 26 patients with one crater-like defect, around either sandblasted and acid-etched (SLA) or titanium plasma-sprayed (TPS) dental implants, with a probing depth (PD) ≥6mm and no implant mobility (Roccuzzo etal. J Clin Periodontol. 2011; 38: 738). Implants were mechanically debrided and treated using EDTA gel and chlorhexidine gel. The bone defects were filled with DBBMC, and the flap was sutured around the non-submerged implant. Patients were placed on an individually tailored supportive periodontal therapy (SPT). Two patients were lost to follow-up. During SPT, additional antibiotic and/or surgical therapy was necessary in eight implants, and four of these were removed for biologic complications. At 7-year, the survival rate was 83.3% for SLA implants and 71.4% for TPS. PD was significantly reduced from 6.6±1.3 to 3.2±0.7mm in SLA and 7.2±1.5 to 3.4±0.6mm in TPS. Bleeding on probing decreased from 75.0±31.2% to 7.5±12.1% (SLA) and from 90.0±12.9% to 30.0±19.7% (TPS). When successful therapy was defined as PD ≤5mm, absence of bleeding/suppuration on probing, and no further bone loss, treatment success was obtained in 2 of 14 (14.3%) of the TPS and in 7 of 12 (58.3%) of the SLA implants. Seven years after surgical treatment with DBBMC, patients, in an adequate SPT, maintained sufficient peri-implant conditions in many cases, particularly around SLA implants. Nevertheless, some patients required further treatment and some lost implants. The clinical decision on whether implants should be treated or removed should be based on several factors, including implant surface characteristics.

Evaluation of the osseointegration of dental implants coated with calcium carbonate: an animal study

In an attempt to overcome the limitations of titanium in dental and orthopaedic clinical applications, a new method has been developed to prepare calcium carbonate coatings on sandblasted and acid-etched (SA) titanium implants. The purpose of this study was to investigate the effect of calcium carbonate-SA (CC-SA) implants on osseointegration in vivo. The surfaces of SA and CC-SA implants were characterised for surface morphology and surface chemistry. Subsequently, these two kinds of implants were implanted in the femoral condyles of rabbits. The implants were retrieved and prepared for histological and histomorphometric evaluation 1, 2, 4, 8 and 12 weeks after implantation. Significantly higher values of bone-to-implant contact of the entire implant except the gap area (BIC_ALL) and the bone-to-implant contact of the gap area (BIC_GAP) were found in animals with the CC-SA implants than in those with the SA implants at 4 weeks. Higher values of total gap bone were found in those with the CC-SA implants than in those with the SA implants at 1, 2 and 4 weeks. In conclusion, the current findings demonstrate that the calcium carbonate coating can improve and accelerate the early ingrowth of bone and osseointegration at the early healing phase. This may reduce clinical healing times and thus improve implant success rates.

Efficacy of standard (SLA) and modified sandblasted and acid-etched (SLActive) dental implants in promoting immediate and/or early occlusal loading protocols: a systematic review of prospective studies.

To assess the survival percentage, clinical and radiographic outcomes of sandblasted and acid-etched (SLA) dental implants and its modified surface (SLActive) in protocols involving immediate and early occlusal loading. MEDLINE, EMBASE and the Cochrane Oral Health Group's Trials Register CENTRAL were searched in duplicate up to, and including, June 2013 to include randomised controlled trials (RCTs) and prospective observational studies of at least 6-month duration published in all languages. Studies limited to patients treated with SLA and/or SLActive implants involving a treatment protocol describing immediate and early loading of these implants were eligible for inclusion. Data on clinical and/or radiographic outcomes following implant placement were considered for inclusion. Of the 447 potentially eligible publications identified by the search strategy, seven RCTs comprising a total of 853 implants (8% titanium plasma-sprayed, 41.5% SLA and 50.5% SLActive) and 12 prospective observational studies including 1394 SLA and 145 SLActive implants were included in this review. According to the Cochrane Collaboration's tool for assessing risk of bias, one of the studies was considered to be at a low risk of bias, whereas the remaining studies were considered to be at an unclear risk. Regarding the observational studies, all of them presented a medium methodological quality based on the Modified Newcastle-Ottawa scale. There were no significant differences reported in the studies in relation to implant loss or clinical parameters between the immediate/early loading and delayed loading protocols. Overall, 95% of SLA and 97% of SLActive implants still survive at the end of follow-up. Despite of the positive findings achieved by the included studies, few RCTs were available for analysis for SLActive implants. Study heterogeneity, scarcity of data and the lack of pooled estimates represent a limitation between studies' comparisons and should be considered when interpreting the present findings.

Long‐term results of a three arms prospective cohort study on implants in periodontally compromised patients: 10‐year data around sandblasted and acid‐etched (SLA) surface

The aim of this study was to compare the long-term outcomes of sandblasted and acid-etched (SLA) implants in patients previously treated for periodontitis and in periodontally healthy patients (PHP). One hundred and forty-nine partially edentulous patients were consecutively enrolled in private specialist practice and divided into three groups according to their periodontal condition: PHP, moderately periodontally compromised patients (PCP) and severely PCP. Implants were placed to support fixed prostheses, after successful completion of initial periodontal therapy. At the end of active periodontal treatment (APT), patients were asked to follow an individualized supportive periodontal therapy (SPT) program. Diagnosis and treatment of peri-implant biological complications were performed according to cumulative interceptive supportive therapy (CIST). At 10 years, clinical and radiographic measures were recorded by two calibrated operators, blind to the initial patient classification, on 123 patients, as 26 were lost to follow up. The number of sites treated according to therapy modalities C and D (antibiotics and/or surgery) during the 10 years was registered. Six implants were removed for biological complications. The implant survival rate was 100% for PHP, 96.9% for moderate PCP and 97.1% for severe PCP. Antibiotic and/or surgical therapy was performed in 18.8% of cases in PHP, in 52.2% of cases in moderate PCP and in 66.7% cases in severe PCP, with a statistically significant differences between PHP and both PCP groups. At 10 years, the percentage of implants, with at least one site that presented a PD ≥ 6 mm, was, respectively, 0% for PHP, 9.4% for moderate PCP and 10.8% for severe PCP, with a statistically significant difference between PHP and both PCP groups. This study shows that SLA implants, placed under a strict periodontal control, offer predictable long-term results. Nevertheless, patients with a history of periodontitis, who did not fully adhere to the SPT, presented a statistically significant higher number of sites that required additional surgical and/or antibiotic treatment. Therefore, patients should be informed, from the beginning, of the value of the SPT in enhancing long-term outcomes of implant therapy, particularly those affected by periodontitis.

10‐Year Survival and Success Rates of 511 Titanium Implants with a Sandblasted and Acid‐Etched Surface: A Retrospective Study in 303 Partially Edentulous Patients

This retrospective study assessed the 10-year outcomes of titanium implants with a sandblasted and acid-etched (SLA) surface in a large cohort of partially edentulous patients. Records of patients treated with SLA implants between May 1997 and January 2001 were screened. Eligible patients were contacted and invited to undergo a clinical and radiologic examination. Each implant was classified according to strict success criteria. Three hundred three patients with 511 SLA implants were available for the examination. The mean age of the patients at implant surgery was 48 years. Over the 10-year period, no implant fracture was noted, whereas six implants (1.2%) were lost. Two implants (0.4%) showed signs of suppuration at the 10-year examination, whereas seven implants had a history of peri-implantitis (1.4%) during the 10-year period, but presented with healthy peri-implant soft tissues at examination. The remaining 496 implants fulfilled the success criteria. The mean Plaque Index was 0.65 (±0.64), the mean Sulcus Bleeding Index 1.32 (±0.57), the mean Probing Depth 3.27 mm (±1.06), and the mean distance from the implant shoulder to the mucosal margin value -0.42 mm (±1.27). The radiologic mean distance from the implant shoulder to the first bone-to-implant contact was 3.32 mm (±0.73). The present retrospective analysis resulted in a 10-year implant survival rate of 98.8% and a success rate of 97.0%. In addition, the prevalence of peri-implantitis in this large cohort of orally healthy patients was low with 1.8% during the 10-year period.

Stability, marginal bone loss and survival of standard and modified sand-blasted, acid-etched implants in bilateral edentulous spaces: a prospective 15-month evaluation

Chemical modification of the already proven sand-blasted and acid-etched (SLA) implant had increased its surface wettability and consequent early-term osseointegration characteristics. The aim of this clinical trial was to compare the stability changes, success, survival, peri-implant parameters and marginal bone loss (MBL) of the early-loaded standard (SLA) and modified sand-blasted, acid-etched (modSLA) implants. A total of 96 SLA and modSLA implants were placed in a bi-lateral, cross-arch position to the jaws of 22 patients. Resonance frequency analysis (RFA) was used to measure the implant stability in the surgery and following healing after 1, 3 and 6 weeks. At the stage of loading, a panoramic X-ray was obtained and RFA measurement was repeated for all implants. Implants were restored by metal-ceramic crowns and followed for 1 year to determine the success, survival rate, peri-implant parameters and MBL. Results were compared by one- and two-way ANOVA, log-rank test and generalized linear mixed models (P < 0.05). One modSLA implant was lost after 3 weeks following the surgery yielding to a 100 and 97.91% success rate for SLA and modSLA implants, respectively (P = 0.323). At the loading stage, modSLA implants showed significantly lower MBL (0.18 ± 0.05 mm) than SLA implants (0.22 ± 0.06 mm; P = 0.002). In the loading stage, RFA value of the modSLA implants (60.42 ± 6.82) was significantly higher than the both implant types in the surgical stage (55.46 ± 8.29 and 56.68 ± 8.19), and following 1 (56.08 ± 7.01 and 55.60 ± 9.07) and 3 weeks of healing (55.94 ± 5.95 and 55.40 ± 6.50 for SLA and modSLA implants, respectively). modSLA implants demonstrated a better stability and a reduced MBL at the loading stage. Both SLA and modSLA implants demonstrated a favorable success and survival at the end of 15-month follow-up.

Rotational Resistance of Surface-Treated Mini-Implants

To test the hypothesis that there is no difference in the stability and resistance to rotational moments of early loaded sandblasted and acid-etched (SLA) mini-implants and those of machined-surface implants of the same size and shape. A randomized complete block design was used in 12 skeletally mature male beagle dogs. Ninety-six orthodontic mini-implants were tested. Two types of implants were used: some had SLA surface treatment and some had machined surfaces without coating. After 3 weeks of healing, rotational moments of 150 g were applied. The success rates, maximum torque values, angular momentum, and total energy absorbed by the bone were compared. All values were subjected to mixed-model analysis to evaluate the influence of surface treatment, rotational force direction, and site of implantation. The maximum insertion torque and angular momentum of SLA implants were significantly lower than those of machined implants (P = .034, P = .039). The SLA implants had a significantly higher value for total removal energy than the machined implants (P = .046). However, there were no significant differences in total insertion energy, maximum removal torque, and removal angular momentum between the 2 groups. There was no significant difference between clockwise and counterclockwise rotation in all measurements. SLA mini-implants showed relatively lower insertion torque value and angular momentum and higher total energy during removal than the machined implants, suggesting osseointegration of the SLA mini-implant after insertion.

Effects of decontamination and implant surface characteristics on re‐osseointegration following treatment of peri‐implantitis

Although considerable bone fill may occur following treatment of peri-implantitis, re-osseointegration appears to be limited and unpredictable. To evaluate the effects of various decontamination techniques and implant surface configurations on re-osseointegration of contaminated dental implants. Three months after tooth extraction, implants consisting of a basal part and an exchangeable intraosseous implant cylinder (EIIC) were placed in the mandibles of dogs. The EIIC was machined (M), sandblasted and acid-etched (SLA), or titanium plasma sprayed (TPS). Ligature-induced peri-implantitis was initiated 8 weeks post-implantation and lasted until bone loss reached the junction of the two implant parts. Three treatment modalities were applied: (T1) the EIIC was exchanged for a pristine EIIC; (T2) the EIIC was sprayed in situ with saline; and (T3) the EIIC was removed, cleansed outside the mouth by spraying with saline, steam-sterilized, and remounted. A collagen barrier was placed over each fixture, and 3 months later, samples were processed for histology and histomorphometry. T2 revealed the highest bone-to-implant contact (BIC) level (significantly better than T1 and T3). T2 also yielded the highest bone crest level (significantly better than T1), followed by T3 (significantly better than T1). SLA showed the highest BIC level (significantly better than M), followed by TPS. There were no statistically significant differences in bone crest height between implant types. Both SLA implants and in situ cleansing resulted in the best re-osseointegration and bone fill of previously contaminated implants.

Oral implants placed in bone defects treated with Bio‐Oss®, Ostim®‐Paste or PerioGlas: an experimental study in the rabbit tibiae

To compare the histological features of bone filled with Bio-Oss, Ostim-Paste or PerioGlas placed in defects in the rabbit tibiae by evaluating bone tissue composition and the integration of titanium implants placed in the grafted bone. Two cylindrical bone defects, about 4 mm in diameter and 6 mm in depth, were created in the tibiae of 10 rabbits. The defects were filled with either Bio-Oss, PerioGlas, Ostim-Paste or left untreated, and covered with a collagen membrane. Six weeks later, one titanium sandblasted and acid-etched (SLA) implant was inserted at the centre of each previously created defect. The animals were sacrificed after 6 weeks of healing. Implants placed in bone previously grafted with Bio-Oss, PerioGlas or Ostim-Paste obtained a larger extent of osseointegration, although not statistically significant, than implants placed in non-grafted bone. The three grafting materials seemed to perform in a similar way concerning their contribution towards implant osseointegration. All grafting materials appeared to be osteoconductive, thus leading to the formation of bridges of mineralized bone extending from the cortical plate towards the implants surface through the graft scaffold. Grafting with the above-mentioned biomaterials did not add any advantage to the osseointegration of titanium SLA implants in a self-contained defect.

Early loading of sandblasted and acid‐etched implants: a randomized‐controlled double‐blind split‐mouth study. Five‐year results

The aim of the present split-mouth study is to assess the peri-implant conditions around early-loaded sandblasted and acid-etched (SLA) implants, 5 years after abutment connection and to compare, in the same patients, the results obtained with a standard protocol using identical implants with a TPS surface. Surgical procedure was performed by the same operator and was identical at test (SLA) and control (TPS) sites, in 32 healthy patients. Abutment connection was carried out at 35 N cm 6 weeks postsurgery for test sites and 12 weeks for the controls. Patients were seen regularly, for control and professional cleaning. At 60 months, clinical measures and radiographic bone changes were recorded by the same operator, blind to the type of surface of the implant, on 27 patients, as five patients were lost to follow-up. A total number of 106 implants were examined. No implant was lost. No significant differences were found with respect to the presence of plaque [modified plaque index (mPI) 0.27+/-0.56 vs. 0.32+/-0.54], bleeding on probing (29% vs. 32%), mean pocket depth (3.2+/-1 vs. 3.2+/-1 mm) or mean marginal bone loss (0.32+/-1.04 vs. 0.44+/-1.12 mm) between test and control. Four implants that presented 'spinning' at the time of abutment connection presented no significant differences from the rest of the test sites. The results of this prospective study confirm that SLA implants, under defined conditions, are suitable for early loading at 6 weeks in both the mandible and the maxilla. Limited implant spinning, occasionally found at abutment connection, produces no detrimental effect on the clinical outcome when properly handled.

Biomechanical evaluation of the interfacial strength of a chemically modified sandblasted and acid‐etched titanium surface

The functional capacity of osseointegrated dental implants to bear load is largely dependent on the quality of the interface between the bone and implant. Sandblasted and acid-etched (SLA) surfaces have been previously shown to enhance bone apposition. In this study, the SLA has been compared with a chemically modified SLA (modSLA) surface. The increased wettability of the modSLA surface in a protein solution was verified by dynamic contact angle analysis. Using a well-established animal model with a split-mouth experimental design, implant removal torque testing was performed to determine the biomechanical properties of the bone-implant interface. All implants had an identical cylindrical shape with a standard thread configuration. Removal torque testing was performed after 2, 4, and 8 weeks of bone healing (n = 9 animals per healing period, three implants per surface type per animal) to evaluate the interfacial shear strength of each surface type. Results showed that the modSLA surface was more effective in enhancing the interfacial shear strength of implants in comparison with the conventional SLA surface during early stages of bone healing. Removal torque values of the modSLA-surfaced implants were 8-21% higher than those of the SLA implants (p = 0.003). The mean removal torque values for the modSLA implants were 1.485 N m at 2 weeks, 1.709 N m at 4 weeks, and 1.345 N m at 8 weeks; and correspondingly, 1.231 N m, 1.585 N m, and 1.143 N m for the SLA implants. The bone-implant interfacial stiffness calculated from the torque-rotation curve was on average 9-14% higher for the modSLA implants when compared with the SLA implants (p = 0.038). It can be concluded that the modSLA surface achieves a better bone anchorage during early stages of bone healing than the SLA surface; chemical modification of the standard SLA surface likely enhances bone apposition and this has a beneficial effect on the interfacial shear strength.