Implant Surface Characteristics Research Articles

Bone Formation and Remodeling of Three Different Dental Implant Surfaces with Escherichia Coli–Derived Recombinant Human Bone Morphogenetic Protein 2 in a Rabbit Model

The objective of this study was to analyze orthotropic bone formation and remodeling of three different dental implant surfaces with and without recombinant human bone morphogenetic protein 2 derived from Escherichia coli (ErhBMP-2) in a rabbit model. Resorbable blasting media (RBM); sandblasted, large-grit, acid-etched (SLA); and magnesium-incorporated oxidized (MgO) implant surfaces were coated with ErhBMP-2 (1.5 mg/mL). The implants were placed into the proximal tibia in six New Zealand White rabbits. Each rabbit received six different implants (three coated with ErhBMP-2 in one tibia and three uncoated implants in the other tibia), and the sites were closed, submerging the implants. The animals received alizarin (at 2 weeks), calcein (at 4 weeks), and tetracycline (at 6 weeks) fluorescent bone markers, and were euthanized at 8 weeks for histomorphometric analysis. The amount of ErhBMP-2 coating was 9.6 ± 0.4 μg per MgO implant, 14.5 ± 0.6 μg per RBM implant, and 29.9 ± 3.8 μg per SLA implant. Clinical healing was uneventful. Mean bone-to-implant contact (± standard deviation) for the ErhBMP-2/RBM (35.4% ± 5.1%) and ErhBMP-2/MgO (33.4 % ± 13.2%) implants was significantly greater compared with RBM (23.6% ± 6.2%) and MgO (24.9% ± 2.7%) implants (P < .05). Considering the mean bone-to-implant contact in cortical bone, ErhBMP-2/SLA implants (32.9% ± 7.8%) showed lower bone-to-implant contact in cortical bone than all other implant variations (range, 39.9% ± 18.1% to 51.3% ± 9.2%; P < .05). There were no remarkable differences in new bone area, with minor differences between implants. Within the limits of study, it was found that the absorbed ErhBMP-2 dose varied with implant surface characteristics, influencing local bone formation and remodeling.

Experimental periodontitis and peri‐implantitis in dogs

To analyze the tissue reactions following ligature removal in experimental periodontitis and peri-implantitis in dogs. Four implants with similar geometry and with two different surface characteristics (turned/TiUnite Nobel BioCare AB, Göteborg) were placed pair-wise in a randomized order in the right side of the mandible 3months after tooth extraction in 5 dogs. Experimental peri-implantitis and periodontitis were initiated 3months later by ligature placement around implants and mandibular premolars and plaque formation. The ligatures were removed after 10weeks, and block biopsies were obtained and prepared for histological analysis 6months later. It was demonstrated that the amount of bone loss that occurred during the period following ligature removal was significantly larger at implants with a modified surface than at implants with a turned surface and at teeth. The histological analysis revealed that peri-implantitis sites exhibited inflammatory cell infiltrates that were larger, extended closer to the bone crest and contained larger proportions of neutrophil granulocytes and osteoclasts than in periodontitis. It is suggested that lesions produced in experimental periodontitis, and peri-implantitis are different and that implant surface characteristics influence the inflammatory process in experimental peri-implantitis and the magnitude of the resulting tissue destruction.

Peri‐implant bone formation and surface characteristics of rough surface zirconia implants manufactured by powder injection molding technique in rabbit tibiae

To evaluate osseointegration in rabbit tibiae and to investigate surface characteristics of novel zirconia implants made by powder injection molding (PIM) technique, using molds with and without roughened inner surfaces. A total of 20 rabbits received three types of external hex implants with identical geometry on the tibiae: machined titanium implants, PIM zirconia implants without mold etching, and PIM zirconia implants with mold etching. Surface characteristics of the three types of implant were evaluated. Removal torque tests and histomorphometric analyses were performed. The roughness of PIM zirconia implants was higher than that of machined titanium implants. The PIM zirconia implants exhibited significantly higher bone-implant contact and removal torque values than the machined titanium implants (P<0.001). The PIM zirconia implants using roughened mold showed significantly higher removal torque values than PIM zirconia implants without using roughened mold (P<0.001). It is concluded that the osseointegration of PIM zirconia implant is promising and PIM using roughened mold etching technique can produce substantially rough surfaces on zirconia implants.

Comparison Between Bioactive Fluoride Modified and Bioinert Anodically Oxidized Implant Surfaces in Early Bone Response Using Rabbit Tibia Model

The aim of this study was to investigate whether bioactive surfaces were more favorable to bone than bioinert surfaces by evaluating bone responses around two commercial dental implants. Bioactive fluoride-modified implants (Osseospeed) were compared with bioinert oxidized implants (TiUnite). Field emission scanning electron microscopy, energy dispersive spectroscopy, and confocal laser scanning microscopy analyzed the implant surface characteristics. Five New Zealand white rabbits were used to evaluate the bone response. Each rabbit received two implants: a fluoride-modified implant in one tibia and an oxidized implant in the other. Drilling was performed bicortically, and a gap defect was created in the upper cortexonly. Bone-to-implant contact and bone area were measured on the histological specimens 2 weeks after implant insertion. No significant differences were found in surface roughness (P > 0.05). The gap defects were almost filled with new bone within a period of 2 weeks. The histomorphometry revealed no significant differences in bone-to-implant contact and bone area (P > 0.05). Within the limitation of this study, the bioactive fluoride-modified surface may show no superiority to the bioinert anodized surface in early bone response.

Dental Implants in Posterior Maxilla: Diagnostic and Treatment Aspects

Dental implantology is one of the most popular and intensively researched topics of current dental medicine. The necessity for the former complicated preprosthetic surgical procedures to facilitate the partial dentures has recently been decreased with the widespread construction of implant-supported prosthesis. Nevertheless, the alveolar deficiency that impedes the insertion of dental implants makes a number of similar reconstructive procedures inevitable. The posterior maxilla is one of the most challenging anatomic locations for the implant placement that requires adjunctive surgical procedures. This special issue covers leading researches and reviews on this topic that we believe would contribute to clinicians. Insufficient bone quality and quantity in posterior maxilla is a common clinical state which makes the implant applications challenging in this site. The main reason for that is the pneumatization of sinus subsequent to the tooth loss and the concomitant excessive alveolar resorption. Insufficient subantral bone and coexisting increased interarch distance necessitate a combined sinus lifting and augmentation procedures. T. Kanno et al. reported the results of their retrospective study entitled “Simultaneous sinus lifting and alveolar distraction of a severely atrophic posterior maxilla for oral rehabilitation with dental implants” in which they performed combined sinus lifting and alveolar distraction osteogenesis in a case series with 27 individuals. The study revealed a histomorphometric similarity between the new bone formed by the presented technique and the bone generated via the sinus lifting only. They also accomplished stable implant rehabilitations within this topic. The quality and the quantity of the host bone are the key determinants for successful dental implants. The quantity of the bone may be estimated via advanced radiological techniques in a high precision. However, a definitive accuracy cannot be pronounced although a number of techniques are available to evaluate the quality of bone. H. Bilhan et al. have reviewed the current techniques used for the estimation of the quality of the host bone while they simultaneously reported the results of a pilot experimental study that compares the densitometric evaluation of the dental volumetric tomography (DVT) with micro CT with their study entitled “How precise is dental volumetric tomography in the prediction of bone density?”. The results of this study revealed that the Hounsfield unit evaluation via DVT is not a reliable method to evaluate the density of bone. C. Riben and A. Thor have published their review on “graftless augmentation procedures” which became a popular topic on sinus floor elevation, regarding a conventional surgical approach for the posterior maxillae. Their study entitled “The maxillary sinus membrane elevation procedure: augmentation of bone around dental implants without grafts—a review of a surgical technique” includes the technical details of the procedure. The alveolar bone loss principally initiates with the tooth loss and this state may complicate the ideal placement of the implants. A number of surgical methods is advocated to prevent the bone loss. G. Pagni et al. reviewed these techniques in their study entitled “Postextraction alveolar ridge preservation in the molar area: biological basis and treatments”. The study provides comprehensive information about the socket healing and biology of the alveoloar bone resorption subsequent to extraction. They stated that the improvements in the grafting technologies would give rise to less invasive surgical interventions. The recent advances in the implant surface characteristics led to major modifications in former fundamentals. An increased osseointegration rate with the improvement of the surface characteristics of dental implants resulted in a numerous successful reports for the implants shorter than 10 mm. Today, many companies appear in the dental market with their recently introduced 6 mm or shorter dental implants. Owing to this, clinicians now can be able to offer effective and noninvasive remedies to their patients avoiding advanced complicated surgeries in case of severe alveolar atrophy. Although a number of clinical reports reveals high success rates for the mandible, the use of short implants in the maxilla is still debatable especially for the single-tooth replacements due to its porous nature. D. Lops et al. compared the clinical success rates for 8 mm. Implants with that of 10 mm. In their long-term study entitled “Short implants in partially edentulous maxillae and mandibles: a 10 to 20 years retrospective evaluation”. In general, they declared similar success rates for 8 mm and longer implants. The results of this study revealed that the use of 8 mm implants seems to be safe in the posterior maxilla.

Characterization of Ti and Ti6Al4V Surfaces After Mechanical and Chemical Treatments: A Rational Approach to the Design of Biomedical Devices

At present, titanium-based biomaterials for the production of prosthetic devices have achieved a satisfactory quality level; current research aims at improving their surgical dependability and biomechanical performances. In this contest, a crucial aspect is represented by the osseointegration process, which implies the secure association of endosseous devices with the surrounding biological tissue. Osseointegration is largely controlled by surface characteristics with regard to both chemical composition and morphological properties. Therefore, the design of such devices might be guided by the characterization of surface morphology produced by mechanical and chemical treatments. This paper illustrates the results obtained by the application of a set of treatments on titanium (Ti2) and Ti6Al4V alloy (Ti5) samples. Mechanical treatments mainly affect the dimension of larger defects, acting on a macrometric scale and inducing specific patterns; chemical treatments (i.e., acid attack at room or higher temperature) can dissolve surface material altering defect dimensions on a micrometric scale. This study may represent a useful tool for the rational design of implant surface characteristics.

Spontaneous progression of experimental peri‐implantitis at implants with different surface characteristics: An experimental study in dogs

To analyse spontaneous progression of ligature-induced peri-implantitis at implants with different surface characteristics. Four implants with similar geometry and with two different surface characteristics (turned/TiUnite; Nobel Biocare AB) were placed pairwise in one side of the mandible in five dogs, 3 months after tooth extraction. Experimental peri-implantitis was initiated by placement of ligatures and plaque formation. The ligatures were removed when about 40% of the supporting bone was lost. After 6 months, block biopsies were obtained and prepared for histological analysis. The amount of bone loss that occurred during the plaque accumulation period after ligature removal was significantly larger at implants with a TiUnite surface than at implants with a turned surface. The histological analysis revealed that the vertical dimensions of the lesion and the pocket epithelium and the apical extension of the biofilm were significantly larger at TiUnite implants than at turned implants. It is suggested that the implant surface characteristics influence progression of peri-implantitis.

Analysis of the release characteristics of cu-treated antimicrobial implant surfaces using atomic absorption spectrometry.

New developments of antimicrobial implant surfaces doped with copper (Cu) ions may minimize the risk of implant-associated infections. However, experimental evaluation of the Cu release is influenced by various test parameters. The aim of our study was to evaluate the Cu release characteristics in vitro according to the storage fluid and surface roughness. Plasma immersion ion implantation of Cu (Cu-PIII) and pulsed magnetron sputtering process of a titanium copper film (Ti-Cu) were applied to titanium alloy (Ti6Al4V) samples with different surface finishing of the implant material (polished, hydroxyapatite and corundum blasted). The samples were submersed into either double-distilled water, human serum, or cell culture medium. Subsequently, the Cu concentration in the supernatant was measured using atomic absorption spectrometry. The test fluid as well as the surface roughness can alter the Cu release significantly, whereby the highest Cu release was determined for samples with corundum-blasted surfaces stored in cell medium.

A 5‐Year Prospective Multicenter Clinical Trial of Non‐Submerged Dental Implants With a Titanium Plasma‐Sprayed Surface in 200 Patients

Endosseous dental implants are a popular treatment to replace missing teeth. Although many advances have occurred and affected the macrogeometry and surface characteristics of dental implants, among other aspects, it is important to document how the implants perform in patients over time. Such evaluations are helpful not only to document the clinical survival of the implants but also patient satisfaction over an extended period. A formal prospective multicenter human clinical was performed at five centers involving 200 patients and 626 implants. Specific inclusion and exclusion criteria were used and detailed data collected at specified times using case report forms. An independent study monitor reviewed all study data before entry into the study database. Two implant designs were used in two different clinical indications. A non-submerged titanium plasma-sprayed (TPS) hollow cylindrical implant with a smooth transgingival collar was evaluated in the maxillary anterior sextant and a non-submerged TPS solid screw implant with similar collar in the mandible. Over the course of the 5-year clinical trial, there was one early failure occurring before definitive prosthesis delivery. Three late failures were documented, one occurring at each of the 6, 12, and 18 months postoperative visits. Life table analysis at 5 years revealed a 99.4% survival rate and a 92.5% success rate. Patient satisfaction was rated as good to excellent for 96.1% of implants in regards to esthetics after 5 years; 98.8% for appearance; and 99.4% for prosthesis comfort, ability to chew and taste, fit, and general satisfaction. No serious adverse events were reported. Implant success and survival was over 92% and 99%, respectively, in a formal 5-year prospective multicenter clinical trial involving 200 patients and 626 non-submerged TPS implants. These implants included hollow cylinder implants in the anterior maxilla and solid screw implants placed in the mandible. These findings document the predictability and patient satisfaction of tooth replacement using a non-submerged surgical technique involving a tissue-level, rough surfaced endosseous dental implant.

Influence of various implant platform configurations on peri-implant tissue dimensions: an experimental study in dog

To evaluate the influence (i) of various implant platform configurations and (ii) of implant surface characteristics on peri-implant tissue dimensions in a dog model. Mandibular premolars and first molars were extracted bilaterally in six Labrador dogs. After 3 months of healing, two implants, one with a turned and a second with a moderately rough surface, were installed on each side of the mandible in the premolar region. On the right side of the mandible, implants with a tapered and enlarged platform were used, while standard cylindrical implants were installed in the left side of the mandible. Abutments with the diameter of the cylindrical implants were used resulting in a mismatch of 0.25 mm at the tapered implant sites. The flaps were sutured to allow a non-submerged healing. After 4 months, the animals were sacrificed and ground sections were obtained for histometric assessment. All implants were completely osseointegrated. A minimal buccal bone resorption was observed for both implant configurations and surface topographies. Considering the animals as the statistical unit, no significant differences were found at the buccal aspect in relation to bone levels and soft tissue dimensions. The surface topographies did not influence the outcomes either. The present study failed to show differences in peri-implant tissue dimensions when a mismatch of 0.25 mm from a tapered platform to an abutment was applied. The surface topographies influence a neither marginal bone resorption or peri-implant soft tissue dimension.

How do implant surface characteristics influence peri‐implant disease?

To review the literature on how implant surface characteristics influence peri-implant disease. A search of PubMed and The Cochrane Library of the Cochrane Collaboration (CENTRAL) as well as a hand search of articles were conducted. Publications and articles accepted for publication up to March 2010 were included. Thirteen studies were selected for the review. Human studies: To date, few studies have investigated if such differences occur. Limited data suggest that smooth surfaces may be less affected by peri-implantitis than rough surface implants. Animal studies: In ligature-induced peri-implantitis studies, no difference between surfaces has been reported. In a spontaneous progression model of peri-implantitis, there was a suggestion that the progression was more pronounced at implants with a porous anodized surface. The current review revealed that only a few studies provided data on how implant surfaces influence peri-implant disease. Based on the limited data available, there is no evidence that implant surface characteristics can have a significant effect on the initiation of peri-implantitis.

Early peri-implant tissue reactions on different titanium surface topographies

The purpose of the present study was to investigate the early peri-implant soft tissue healing on different titanium surface topographies. Titanium implants with smooth or rough surfaces were placed in the extraction site at 1 month after the maxillary first molar extractions of 15 male Sprague-Dawley rats. At 4 and 7 days after implant surgery, the peri-implant oral mucosa was randomly harvested and analyzed for collagen fiber orientation, and expression of extracellular matrix genes. Descriptive and paired t-tests were performed where appropriate (α = 0.05). The laser scanning microscopic analysis of the Sirius red stained peri-implant connective tissue revealed a parallel and uniform collagen fiber orientation along the smooth implant at both 4 and 7 days. In contrast, the collagen fibers of the comparative peri-implant tissue from rough surface implants at 7 days were not arranged in parallel orientation but in an irregular a "cotton-ball-like." The levels of mRNA of types III and XII collagen and transforming growth factor-β1 significantly increased in the smooth implant group compared with the rough implant group at both 4 and 7 days or either one of days. The results of this study suggest that implant surface characteristics may affect early events of soft tissue healing by influencing collagen fiber orientation and expression of key genes for initial healing.

Implant surface characteristics influence the outcome of treatment of peri-implantitis: an experimental study in dogs

To analyse the effect of surgical treatment of peri-implantitis without systemic antibiotics at different types of implants. Four implants representing four different implant systems - turned (Biomet 3i), TiOblast (Astra Tech AB), SLA (Straumann AG) and TiUnite (Nobel Biocare AB) were placed in the left side of the mandible in six dogs, 3 months after tooth extraction. Experimental peri-implantitis was initiated by placement of ligatures and plaque formation. The ligatures were removed when about 40-50% of the supporting bone was lost. Four weeks later, surgical therapy including mechanical cleaning of implant surfaces was performed. No systemic antibiotics or local chemical antimicrobial therapy were used. After 5 months, block biopsies were obtained and prepared for histological analysis. Two of the TiUnite implants were lost after surgical therapy. Radiographic bone gain occurred at implants with turned, TiOblast and SLA surfaces, while at TiUnite implants additional bone loss was found after treatment. Resolution of peri-implantitis was achieved in tissues surrounding implants with turned and TiOblast surfaces. Resolution of peri-implantitis following treatment without systemic or local antimicrobial therapy is possible but the outcome of treatment is influenced by implant surface characteristics.

In vitro and in vivo mineralization and osseointegration of nanostructured Ti6Al4V

Surface characteristics of the orthopedic implants remarkably affect the corresponding biological responses. In this study, Ti6Al4V alloy was subjected to the surface mechanical attrition treatment (SMAT) in order to achieve favorable surface properties. The SMAT substrates exhibited a highly hydrophilic surface with nanograins about 20–40 nm. Then, the in vitro and in vivo mineralizations were evaluated on the untreated and SMAT processed substrates. The in vitro experimental results showed a significant increase in the deposition of calcium-containing minerals on the SMAT surface both with and without osteoblasts. The in vivo experiments also revealed a higher bone mineral apposition on the SMAT processed implants after 8 and 12 weeks post operation. The well-organized bone formation on the SMAT substrates indicated an enhanced osseointegration on the bone-implant interface. Therefore, it was suggested that the obvious improvements of biomineralization and osseointegration were attributed to the nanostructure features on the SMAT surface, as well as the higher surface hydrophilicity.

Comparative biology of chronic and aggressive periodontitis vs. peri-implantitis

This review was undertaken to address the similarities and dissimilarities between the two disease entities of periodontitis and peri-implantitis. The overall analysis of the literature on the etiology and pathogenesis of periodontitis and peri-implantitis provided an impression that these two diseases have more similarities than differences. First, the initiation of the two diseases is dependent on the presence of a biofilm containing pathogens. While the microbiota associated with periodontitis is rich in gram-negative bacteria, a similar composition has been identified in peri-implant diseases. However, increasing evidence suggests that S. aureus may be an important pathogen in the initiation of some cases of peri-implantitis. Further research into the role of this gram-positive facultative coccus, and other putative pathogens, in the development of peri-implantitis is indicated. While the initial host response to the bacterial challenge in peri-implant mucositis appears to be identical to that encountered in gingivitis, persistent biofilm accumulation may elicit a more pronounced inflammatory response in peri-implant mucosal tissues than in the dentogingival unit. This may be a result of structural differences (such as vascularity and fibroblast-to-collagen ratios). When periodontitis and peri-implantitis were produced experimentally by applying plaque-retaining ligatures, the progression of mucositis to peri-implantitis followed a very similar sequence of events as the development of gingivitis to periodontitis. However, some of the peri-implantitis lesions appeared to have periods of rapid progression, in which the infective lesion reached the alveolar bone marrow. It is therefore reasonable to assume that peri-implantitis in humans may also display periods of accelerated destruction that are more pronounced than that observed in cases of chronic periodontitis. From a clinical point of view the identified and confirmed risk factors for periodontitis may be considered as identical to those for peri-implantitis. In addition, patients susceptible to periodontitis appear to be more susceptible to peri-implantitis than patients without a history of periodontitis. As both periodontitis and peri-implantitis are opportunistic infections, their therapy must be antiinfective in nature. The same clinical principles apply to debridement of the lesions and the maintenance of an infection-free oral cavity. However, in daily practice, such principles may occasionally be difficult to apply in peri-implantitis treatment. Owing to implant surface characteristics and limited access to the microbial habitats, surgical access may be required more frequently, and at an earlier stage, in periimplantitis treatment than in periodontal therapy. In conclusion, it is evident that periodontitis and peri-implantitis are not fundamentally different from the perspectives of etiology, pathogenesis, risk assessment, diagnosis and therapy. Nevertheless, some difference in the host response to these two infections may explain the occasional rapid progression of peri-implantitis lesions. Consequently, a diagnosed peri-implantitis should be treated without delay.

Influence of titanium implant surface characteristics on bone regeneration in dehiscence‐type defects: an experimental study in dogs

The aim of the present study was to compare bone regeneration in dehiscence-type defects at titanium implants with chemically modified sandblasted/acid-etched (modSLA) or dual acid-etched surfaces with a calcium phosphate nanometre particle modification (DCD/CaP). Buccal dehiscence-type defects were surgically created following implant site preparation in both the upper and the lower jaws of 12 fox hounds. Both types of implants were randomly allocated in a split-mouth design and left to heal in a submerged position for 2 and 8 weeks. Dissected blocks were processed for histomorphometrical analysis [e.g. new bone height (NBH), percentage of bone-to-implant contact (BIC), area of new bone fill (BF), and area of mineralized tissue (MT) within BF]. At 2 and 8 weeks, both groups revealed comparable mean BF (2.3+/-0.6 to 2.5+/-0.6 mm(2)versus 2.0+/-0.6 to 1.4+/-0.5 mm(2)) and MT (31.1+/-14.3-83.2+/-8.2%versus 38.9+/-15.9-84.4+/-6.3%) values. However, modSLA implants revealed significantly higher mean NBH (2.4+/-0.8 to 3.6+/-0.3 mm versus 0.9+/-0.8 to 1.8+/-1.4 mm) and BIC (53.3+/-11.3-79.5+/-6.6%versus 19.3+/-16.4-47.2+/-30.7%) values than DCD/CaP implants. ModSLA implants may have a higher potential to support osseointegration in dehiscence-type defects than DCD/CaP implants.

An in vitro multi-parametric approach to measuring the effect of implant surface characteristics on cell behaviour

Orthopaedic implants are designed to promote biocompatibility and hence their integration with surrounding tissue. This involves influencing cell–implant interactions through changes in both surface topography and surface roughness. However, the large range of machining techniques used in implant manufacture and inconsistencies in the measurement techniques used for surface characterization make it difficult to measure the impact of surface characteristics on cell–implant interactions. Here, we describe a new in vitro multi-parametric approach that uses commercially available arrays of engineered surfaces that linearly increase in roughness, as measured by Ra, and that can be used to obtain quantitative measurements of cell attachment, differentiation and bone formation. Using this model, we demonstrate that cell attachment above 50% confluency occurs over a narrow range of roughness (Ra from 0.0125 µm to 6.3 µm) and that promotion of cell differentiation and bone development, while significantly influenced by surface topography, does not correlate directly with initial levels of cell attachment. These results compare well with published in vivo implant biocompatibility data indicating that this approach has the potential to offer a rapid, reliable and reproducible in vitro prediction of in vivo implant biocompatibility.

Re‐osseointegration on previously contaminated surfaces: a systematic review

The aim of this review was to search the literature for the existing evidence of re-osseointegration after treatment of peri-implantitis at contaminated implant surfaces. A search of PubMed as well as additional hand search of articles were conducted. Publications and articles accepted for publication up to November 2008 were included. A total of 25 animal studies fulfilled the inclusion criteria for this review. Access surgery with closed healing has been observed to positively influence the rate of re-osseointegration when compared with non-surgical decontamination of the implant surface with open healing. Open debridement including surface decontamination may result in re-osseointegration and this integration was more pronounced on rougher than on smooth implant surfaces. The adjunctive use of regenerative procedures resulted in varying amounts of re-osseointegration. Re-osseointegration is possible to obtain on a previously contaminated implant surface and can occur in experimentally induced peri-implantitis defects following therapy. The amount of re-osseointegration, varied considerably within and between studies. Implant surface characteristics may influence the degree of re-osseointegration. Surface decontamination alone can not achieve substantial re-osseointegration on a previously contaminated implant surface. No method predictably accomplished complete resolution of the peri-implant defect.

Effects of different implant surfaces and designs on marginal bone‐level alterations: a review

The purpose of this review was to evaluate the effect of different implant surfaces and designs on marginal bone-level (MBL) alterations. A MEDLINE search (PubMed) was performed to identify clinical, prospective and controlled studies using a sufficient sample size (>10 subjects) and with a follow-up time of > or =3 years. Ten publications fulfilled the inclusion criteria. Two studies evaluated the influence of implant surface characteristics and two studies reported on the effect of implant design on MBL changes. Six publications analyzed the combined effect of different implant surfaces and designs on MBL alterations. As revealed from available studies, there is no evidence that modified surfaces are superior to non-modified implant surfaces in marginal bone preservation. One study reported on significantly improved MBL preservation for implants with a conical and micro-threaded marginal collar than implants with a cylindrical and non-threaded marginal portion after 3 years in function. No implant system was found to be superior in marginal bone preservation.

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.