Implant Surface Analysis and Microbiologic Evaluation of Failed Implants Retrieved From Smokers

Effect of preoperative chlorhexidine, essential oil, and cetylpyridinium chloride mouthwashes on bacterial contamination during dental implant surgery: A randomized controlled clinical trial

Background

Although the role of chlorhexidine and other mouthwashes in periodontal therapy has been elucidated, little information is available on their use as routine preoperative mouth rinses before surgery, especially in periodontal procedures such as dental implant surgery.

Objective

This study aimed to compare the efficacy of preoperative chlorhexidine, essential oil, and cetylpyridinium chloride mouthwashes in reducing bacterial contamination at the time of implant placement.

Materials and Methods

Eligible patients who underwent dental implant surgery were randomly divided into four groups based on the mouthwash used: (1) 0.12 % chlorhexidine, (2) essential oil, (3) cetylpyridinium chloride, and (4) saline (served as the control group). All the patients of each group rinsed preoperatively with 15 mL of the respective mouthwash for 60 s. Saliva samples before (pre) and immediately after rinsing with the mouthwash (post) and after suturing the flap (end) were collected on the day of the implant placement. Real-time quantitative polymerase chain reaction (qPCR) was performed to analyze the samples and quantify the targeted periodontal pathogens using a propidium monoazide (PMA) dye.

Results

Forty patients were included in the study. Real-time qPCR demonstrated a significant reduction in the number of pathogens in the saliva samples of the mouthwash groups compared to that of the control group. A statistically significant difference was observed between the groups for the pre-post and pre-end samples (p < 0.001) but not for the post-end samples (p = 0.203). A statistically significant difference was observed between the chlorhexidine, essential oil, and cetylpyridinium chloride mouthwash groups and the saline group (P < 0.001). The bacterial counts significantly differed with and without the use of the PMA dye.

Conclusions

Preoperative chlorhexidine, essential oil, and cetylpyridinium chloride mouthwashes can reduce the bacterial load at the time of implant placement, thereby reducing the incidence of implant-related complications.

Evaluation of Surface Change and Roughness in Implants Lost Due to Peri-Implantitis Using Erbium Laser and Various Methods: An In Vitro Study

The aim of our study was to obtain similar surface properties and elemental composition to virgin implants after debridement of contaminated titanium implant surfaces covered with debris. Erbium-doped:yttrium, aluminum, and garnet (Er:YAG) laser, erbium, chromium-doped:yttrium, scandium, gallium, and garnet (Er,Cr:YSGG) laser, curette, and ultrasonic device were applied to contaminated implant surfaces. Scanning electron microscopy (SEM) images were taken, the elemental profile of the surfaces was evaluated with energy dispersive X-ray spectroscopy (EDX), and the surface roughness was analyzed with profilometry. Twenty-eight failed implants and two virgin implants as control were included in the study. The groups were designed accordingly; titanium curette group, ultrasonic scaler with polyetheretherketone (PEEK) tip, Er: YAG very short pulse laser group (100 μs, 120 mJ/pulse 10 Hz), Er: YAG short-pulse laser group (300 μs, 120 mJ/pulse, 10 Hz), Er: YAG long-pulse laser group (600 μs, 120 mJ/pulse, 10 Hz), Er, Cr: YSGG1 laser group (1 W 10 Hz), Er, Cr: YSGG2 laser group (1.5 W, 30 Hz). In each group, four failed implants were debrided for 120 s. When SEM images and EDX findings and profilometry results were evaluated together, Er: YAG long pulse and ultrasonic groups were found to be the most effective for debridement. Furthermore, the two interventions have shown the closest topography of the sandblasted, large grit, acid-etched implant surface (SLA) as seen on virgin implants.

Chemical Evaluation of Energy Dispersive X-ray Spectroscopy Analysis of Different Failing Dental Implant Surfaces: A Comparative Clinical Trial

The aim of the present study is to compare two different implant surface chemistries of failing dental implants. Sixteen patients (mean age: 52 ± 8.27 with eight females and eight males) and 34 implants were included in the study. Group-I implants consisted of a blasted/etched surface with a final process surface, while Group-II implants consisted of the sandblasted acid etching (SLA) method. The chemical surface analysis was performed by the energy dispersive X-ray spectroscopy (EDX) method from coronal, middle, and apical parts of each implant. Titanium (Ti) element values were found to be 20.22 ± 15.7 at.% in Group I and 33.96 ± 13.62 at.% in Group-II in the middle of the dental implants. Aluminum (Al) element values were found to be 0.01 ± 0.002 in Group-I and 0.17 ± 0.28 at.% in Group II in the middle of the dental implants, and statistically significant differences were found between the groups for the Al and Ti elements in the middle of the dental implants (p < 0.05). There was a statistically significant difference for the Ti, Al, O, Ca, Fe, P, and Mg elements in the coronal, middle, and apical parts of the implants in the intragroup evaluation (p < 0.05). It is reported that different parts of the implants affected by peri-implant inflammation show different surface chemistries, from coronal to apical, but there is no difference in the implants with different surfaces.

Decontamination of Dental Implant Surfaces by the Er:YAG Laser Beam: A Comparative in Vitro Study of Various Protocols

Oral rehabilitation with dental implants has revolutionized the field of dentistry and has been proven to be an effective procedure. However, the incidence of peri-implantitis has become an emerging concern. The efficacy of the decontamination of the implant surface, by means of lasers, is still controversial. Previous studies have revealed a reduction in osteoblast adhesion to carbon-contaminated implant surfaces. This in-vitro study aimed to evaluate the decontamination of failed implants by assessing the carbon proportion, after irradiation by low-energy erbium yttrium-aluminum-garnet laser (Er:YAG) (Fotona; 2940 nm, Ljubljana, Slovenia) for a single and for multiple passages, until getting a surface, free of organic matters; to find the appropriate procedure for dental-implant surface-decontamination. Ninety implants were used. Thirty sterile implants were kept as a negative control. Thirty failed implants were irradiated by the Er:YAG laser, for a single passage, and the other thirty, for multiple passages. The parameters used in our experiments were an irradiation energy of 50 mJ, frequency of 30 Hz, and an energy density of 3.76 J/cm². A sapphire tip, with a length of 8 mm, was used with concomitant water spray irrigation, under air 6 and water spray 4. Super short pulse mode (SSP) was of 50 μs; irradiation speed being 2 mm/s. We used energy-dispersive X-ray spectroscopy (EDX) to evaluate the carbon proportion on the surfaces of the sterile implants, the contaminated, and the lased implants, with one (LX1) and with three passages (LX3). Statistical analysis was performed by ANOVA. Results showed mean difference between the three groups (contaminated, LX1, and LX3) with p < 0.0001, as between LX1 and Group A (p < 0.0001), while the difference between LX3 and the control group was not statistically significant. The decontamination of the implant surfaces with a low-energy Er:YAG laser with three passages, appeared to be an encouraging approach.

Cleaning effect of osteoconductive powder abrasive treatment on explanted human implants and biofilm-coated titanium discs

The aim of this study is to test the cleaning effect and surface modification of a new implant surface treatment on explanted dental implants and titanium discs. It is a modified air powder abrasive (APA) treatment applied using osteoconductive powders. Twenty-eight in vitro Ca-precipitated organic film-coated titanium discs and 13 explanted dental implants were treated. In a 2-step approach, 3 powders were used: hydroxylapatite (HA) and biomimetic calcium phosphate (BioCaP), which are osteoconductive, and erythritol, which is not. APA treatment was applied. (Air pressure: 2.4 bar; water flow for cleaning: 41.5 ml/min, for Coating 1: 2.1 ml/min, and for Coating 2: 15.2 ml/min.) The test groups were as follows: Group 1: HA cleaning + BioCaP Coating 1; Group 2: HA cleaning + BioCaP Coating 2; Group 3: erythritol cleaning + BioCaP Coating 1; Group 4: erythritol cleaning + BioCaP Coating 2; Group 5: HA cleaning; Group 6: erythritol cleaning; and control: no powder. Cleaned areas were calculated by point counting method. Surface changes and chemical content were evaluated using light microscopy, scanning electron microscopy, and energy-dispersive X-ray spectroscopy. Cleaning effect between groups was compared by a pairwise Student's t test. The significance level was fixed at p < .05. Cleaning effect on the discs was 100% in all test groups and 5% in the control. Powder particles in varying size and shape were embedded on the surface. All HA- or CaP-treated surfaces showed Ca and P content but no surface damage. Calcified biofilm remnants were removed from the implant surface by the test groups, whereas in control groups, they remained. APA treatment with CaP and HA powders under clinically applicable pressure settings gives positive results in vitro; therefore, they could be promising when used in vivo.

Antimicrobial effect of titanium dioxide after ultraviolet irradiation against periodontal pathogen

We focused on the antimicrobial effects of titanium dioxide (TiO2) after stopping ultraviolet (UV) irradiation as an adjunctive treatment for peri-implantitis in this study. The aim was to determine the continuous photocatalytic effects of TiO2 after UV irradiation and its antimicrobial activity against periodontal pathogen. The continuous photocatalytic effects of TiO2 after UV irradiation were determined by electron spin resonance (ESR) spectroscopy using TiO2 particles of various sizes with various UV irradiation times. In addition, antimicrobial activity against Porphyromonas gingivalis was investigated by quantitation of colony-forming units (CFUs). The results showed that the ESR signal ratio for the UV-irradiated TiO2 was significantly higher than that of the non-irradiated TiO2. UV-irradiated TiO2 significantly reduced the number of P. gingivalis when compared with non-irradiated controls. These results suggest that TiO2 has a continuous photocatalytic effect even after stopping UV irradiation and that it showed antimicrobial activity against periodontal pathogen.

Significance of osteogenic surface coatings on implants to enhance osseointegration under osteoporotic-like conditions

PURPOSE

The aim was to assess the significance of osteogenic surface coatings on implants to enhance osseointegration under osteoporotic-like (OP-like) conditions.

METHODS

To address the focused question "Do osteogenic surface coatings on implants enhance osseointegration under OP-like conditions?" PubMed/MEDLINE and Google-Scholar databases were searched from 1995 up to and including February 2014 using various keywords. Unpublished data, letters to the editor, review articles, and articles published in languages other than English were excluded.

RESULTS

Of the 28 studies identified, 11 experimental studies were included. These studies were performed on bilaterally ovariectomized animals. In all studies, implant surface roughness was increased by various osteogenetic surface coatings including alumina, hydroxyapatite, calcium phosphate, and zoledronic acid. Nine studies reported that compared with non-coated surfaces, osteogenic coatings on implant surfaces increases bone volume and bone-to-implant contact (BIC) under OP-like conditions. In 2 studies, there was no difference in BIC around hydroxyapatite-coated implants placed in animals with and without OP-like conditions.

CONCLUSION

Osteogenic coatings on implant surfaces enhanced osseointegration in animals with OP-like conditions. However, additional clinical studies are warranted to assess the role of osteogenic coatings in increasing osseointegration in patients with osteoporosis.

Oral Streptococci Biofilm Formation on Different Implant Surface Topographies

The establishment of the subgingival microbiota is dependent on successive colonization of the implant surface by bacterial species. Different implant surface topographies could influence the bacterial adsorption and therefore jeopardize the implant survival. This study evaluated the biofilm formation capacity of five oral streptococci species on two titanium surface topographies. In vitro biofilm formation was induced on 30 titanium discs divided in two groups: sandblasted acid-etched (SAE- n = 15) and as-machined (M- n = 15) surface. The specimens were immersed in sterilized whole human unstimulated saliva and then in fresh bacterial culture with five oral streptococci species: Streptococcus sanguinis, Streptococcus salivarius, Streptococcus mutans, Streptococcus sobrinus, and Streptococcus cricetus. The specimens were fixed and stained and the adsorbed dye was measured. Surface characterization was performed by atomic force and scanning electron microscopy. Surface and microbiologic data were analyzed by Student's t-test and two-way ANOVA, respectively (P < 0.05). S. cricetus, S. mutans, and S. sobrinus exhibited higher biofilm formation and no differences were observed between surfaces analyzed within each species (P > 0.05). S. sanguinis exhibited similar behavior to form biofilm on both implant surface topographies, while S. salivarius showed the lowest ability to form biofilm. It was concluded that biofilm formation on titanium surfaces depends on surface topography and species involved.

Bone-to-implant contact around immediately loaded direct laser metal-forming transitional implants in human posterior maxilla

OBJECTIVE

Direct laser metal forming (DLMF) is a procedure in which a high-power laser beam is directed onto a metal powder bed and programmed to fuse particles according to a computer-aided design file, generating a thin metal layer. This histologic study evaluated the bone-to-implant contact (BIC%) around immediately loaded DLMF transitional implants retrieved after 2 months from posterior human maxillae.

METHODS

Twelve totally edentulous individuals (mean age, 66.14 ± 2.11 years) received DLMF transitional implants divided in twelve immediately loaded (IL) and twelve unloaded (UI) implants. These transitional implants were placed between conventional implants to support the interim complete maxillary denture during the healing period. After 8 weeks, the transitional implants and the surrounding tissue were removed and prepared for histomorphometric analysis.

RESULTS

Mature woven preexisting bone lined by newly formed bone in early stages of maturation were found around all retrieved implants. Histometric evaluation indicated that the mean BIC% was 45.20 ± 7.68% and 34.10 ± 7.85% for IL and UI, respectively (P <0.05).

CONCLUSION

The present data obtained in humans showed that, although both IL and UI presented good BIC%, IL DLMF implants had a higher BIC% in the posterior maxilla.

Cleaning and modification of intraorally contaminated titanium discs with calcium phosphate powder abrasive treatment

OBJECTIVE

The aim of this study was to evaluate the cleaning efficiency on intraorally contaminated titanium discs by using calcium phosphate and air powder abrasive (APA) treatment. The modification of titanium surface (SLA) was evaluated and compared with the conventional air powder abrasive methods and phosphoric acid. This treatment modality might give new perspectives for peri-implant surface treatment.

MATERIALS AND METHODS

A total of 36 SLA surface titanium discs were kept in the human mouth for 48 h by 14 volunteers. The intraorally contaminated discs were stained with erythrosine dye to make the biofilm visible. Discs were randomly assigned to one of the six groups: APA without powder-only water and air (Control). APA with Hydroxylapatite (HA). APA with Hydroxylapatite and Calcium Phosphate (HA + TCP). APA with Titanium Dioxide (TiO2). APA with EMS Soft Subgingival powder (EMS). Phosphoric Acid. Light microscope photos were taken during the treatment. Following the cleaning, the residual biofilm, surface changes, and surface chemical content were evaluated using Scanning Electron Microscopy (SEM) and Energy Dispersive X-Ray Spectroscopy (EDS). A systematic random sampling protocol and a point counting method were applied for the quantitative evaluation of the remaining biofilm. Multiple comparisons within and between groups are performed by Kruskall Wallis test and if significant Mann-Whitney U-test as post hoc testing is applied. The significance level was P < 0.05.

RESULTS

All methods with the exception of phosphoric acid could decrease the initial amount of biofilm significantly. Among all air powder abrasive treatments, the HA + TCP group showed the best results with 99% biofilm removal, followed by HA and EMS powders. The cleaning method caused minimal changes to the surface structure. With the exception of the control group, all air powder applications caused sharp edges around the grooves in the implant surface to be rounded. TiO2 powder caused less change than HA and HA + TCP. Phosphoric acid did not cause a visible surface change on the SEM photos. Powder particles remnants were observed on and impacted in the titanium surface. In the HA and HA + TCP group, a Ca content was observed varying between 2% and 5%. In the control group, saliva and biofilm-related elements were observed.

CONCLUSIONS

Using the air powder abrasive method with calcium phosphate powders on contaminated titanium discs, an efficient implant cleaning and surface modification can be achieved. This method should be further improved as it has possible potential to be used as an implant surface treatment method for implants involved with peri-implantitis.

Microbiota associated with infections of the jaws

The microbial infections involving the craniofacial skeleton, particularly maxilla and mandible, have direct relationship with the dental biofilm, with predominance of obligate anaerobes. In some patients, these infections may spread to bone marrow or facial soft tissues, producing severe and life-threatening septic conditions. In such cases, local treatment associated with systemic antimicrobials should be used in order to eradicate the sources of contamination. This paper discuss the possibility of spread of these infections and their clinical implications for dentistry, as well as their etiology and aspects related to microbial virulence and pathogenesis.

Effects of titanium surface topography on bone integration: a systematic review

AIM

To analyse possible effects of titanium surface topography on bone integration.

MATERIALS AND METHODS

Our analyses were centred on a PubMed search that identified 1184 publications of assumed relevance; of those, 1064 had to be disregarded because they did not accurately present in vivo data on bone response to surface topography. The remaining 120 papers were read and analysed, after removal of an additional 20 papers that mainly dealt with CaP-coated and Zr implants; 100 papers remained and formed the basis for this paper. The bone response to differently configurated surfaces was mainly evaluated by histomorphometry (bone-to-implant contact), removal torque and pushout/pullout tests.

RESULTS AND DISCUSSION

A huge number of the experimental investigations have demonstrated that the bone response was influenced by the implant surface topography; smooth (S(a)<0.5 microm) and minimally rough (S(a) 0.5-1 mum) surfaces showed less strong bone responses than rougher surfaces. Moderately rough (S(a)>1-2 microm) surfaces showed stronger bone responses than rough (S(a)>2 microm) in some studies. One limitation was that it was difficult to compare many studies because of the varying quality of surface evaluations; a surface termed 'rough' in one study was not uncommonly referred to as 'smooth' in another; many investigators falsely assumed that surface preparation per se identified the roughness of the implant; and many other studies used only qualitative techniques such as SEM. Furthermore, filtering techniques differed or only height parameters (S(a), R(a)) were reported.

CONCLUSIONS

* Surface topography influences bone response at the micrometre level. * Some indications exist that surface topography influences bone response at the nanometre level. * The majority of published papers present an inadequate surface characterization. * Measurement and evaluation techniques need to be standardized. * Not only height descriptive parameters but also spatial and hybrid ones should be used.

In vitro scanning electron microscopic comparison of inner surface of exposed and unexposed nonresorbable membranes

OBJECTIVE

The purpose of this study was to analyze the attached tissues and the membrane surface condition according to barrier membrane exposure.

STUDY DESIGN

The selected patients underwent implant surgery with guided bone regeneration, then were surgically reentered to remove the membrane when the membrane was exposed early or when the second surgery of implant was done. The membranes used in the study included titanium mesh (Jeil Medical Co., Seoul, Korea), Frios titanium shield (Dentsply Friadent, Mannheim, Germany), and TR-Goretex membrane (W. L. Gore & Associates, CA, USA). Group 1 included 9 cases that had membranes that were exposed during an early period. Each membrane was removed in 3-6 weeks. Group 2 included 8 cases that had membranes that were not exposed and each membrane was removed in 12-24 weeks during the second surgery period of implants. Removed membrane samples were observed with scanning electron microscopy.

RESULTS

The membrane surface condition and the observed tissues were significantly different between the exposed membrane group and the unexposed membrane group (P < .05). In the majority of the cases of early exposed membranes, organic film and soft tissues were observed beneath the membrane. Bony debris was observed in only 1 sample from the exposed group. In the exposed group, the degree of membrane damage was more severe than in the unexposed group. The membrane surface condition and the observed tissues had no significant difference among the 3 kinds of membranes (P > .05).

CONCLUSION

The observed tissues and the membrane surface condition were affected by the membrane exposure. If the membrane is exposed, the soft tissue and organic film interfere with direct contact to the bone, and this affects the barrier membrane surface condition and bony tissues.

A review of dental implants and infection

Dental implants have become increasingly common for the management of tooth loss. Despite their placement in a contaminated surgical field, success rates are relatively high. This article reviews dental implants and highlights factors leading to infection and potential implant failure. A literature search identified studies analysing the microbial composition of peri-implant infections. The microflora of dental peri-implantitis resembles that found in chronic periodontitis, featuring predominantly anaerobic Gram-negative bacilli, in particular Porphyromonas gingivalis and Prevotella intermedia, anaerobic Gram-negative cocci such as Veillonella spp. and spirochaetes including Treponema denticola. The role of Staphylococcus aureus and coagulase-negative staphylococci that are typically encountered in orthopaedic infections is debatable, although they undoubtedly play a role when isolated from clinically infected sites. Likewise, the aetiological involvement of coliforms and Candida spp. requires further longitudinal studies. Currently, there are neither standardised antibiotic prophylactic regimens for dental implant placement nor universally accepted treatment for peri-implantitis. The treatment of infected implants is difficult and usually requires removal. In the UK there is no systematic post-surgical implant surveillance programme. Therefore, the development of such a project would be advisable and provide valuable epidemiological data.