A split-mouth study on microbiological profile in clinical healthy teeth and implants related to key inflammatory mediators

Combination of Poly(ε-Caprolactone) Biomaterials and Essential Oils to Achieve Anti-Bacterial and Osteo-Proliferative Properties for 3D-Scaffolds in Regenerative Medicine

Biomedical implants, an essential part of the medical treatments, still suffer from bacterial infections that hamper patients’ recovery and lives. Antibiotics are widely used to cure those infections but brought antibiotic resistance. Essential oils (EOs) demonstrate excellent antimicrobial activity and low resistance development risk. However, EO application in medicine is still quite scarce and almost no research work considers its use in combination with bioresorbable biomaterials, such as the poly(ε-caprolactone) (PCL) polymer. This work aimed to combine the antibacterial properties of EOs and their components, particularly eugenol and cinnamon oil, against Staphylococcus aureus, S. epidermidis and Escherichia coli, with those of PCL for medical applications in which good tissue regeneration and antimicrobial effects are required. The PCL porous scaffolds, added with increasing (from 30% to 50%) concentrations of eugenol and cinnamon oil, were characterized by square-shaped macropores. Saos-2 cells’ cell viability/proliferation was hampered by 40 and 50% EO-enriched PCL, whereas no cytotoxic effect was recorded for both 30% EO-added PCL and pure-PCL. The antibacterial tests revealed the presence of a small inhibition halo around the 30% eugenol and cinnamon oil-functionalized PCL scaffolds only for staphylococci, whereas a significant decrease on both adherent and planktonic bacteria was recorded for all the three microorganisms, thus proving that, even if the EOs are only in part released by the EO-added PCL scaffolds, an anti-adhesive feature is anyway achieved. The scaffold will have the ability to support new tissue formation and simultaneously will be able to prevent post-surgical infection. This research shows the great potential in the use of EOs or their single components, at low concentrations, for biomaterial functionalization with enhanced anti-bacterial and biointegration properties.

Role of rhBMP-7, Fibronectin, And Type I Collagen in Dental Implant Osseointegration Process: An Initial Pilot Study on Minipig Animals

Background: The biological factors involved in dental implant osseointegration need to be investigated to improve implant success. Methods: Twenty-four implants were inserted into the tibias of six minipigs. Bone samples were obtained at 7, 14, and 56 days. Biomolecular analyses evaluated mRNA of BMP-4, -7, Transforming Growth Factor-β2, Interleukin-1β, and Osteocalcin in sites treated with rhBMP-7, Type 1 Collagen, or Fibronectin (FN). Inflammation and osteogenesis were evaluated by histological analyses. Results: At 7 and 14 days, BMP-4 and BMP-7 increased in the sites prepared with rhBMP-7 and FN. BMP-7 remained greater at 56 days in rhBMP-7 and FN sites. BPM-4 at 7 and 14 days increased in Type 1 Collagen sites; BMP-7 increased from day 14. FN increased the TGF-β2 at all experimental times, whilst the rhBMP-7 only did so up to 7 days. IL-1β increased only in collagen-treated sites from 14 days. Osteocalcin was high in FN-treated sites. Neutrophilic granulocytes characterized the inflammatory infiltrate at 7 days, and mononuclear cells at 14 and 56 days. Conclusions: This initial pilot study, in a novel way, evidenced that Type 1 Collagen induced inflammation and did not stimulate bone production; conversely FN or rhBMP-7 showed neo-osteogenetic and anti-inflammatory properties when directly added into implant bone site.

Biomarkers associated with periodontitis and peri-implantitis: a systematic review

Purpose

The pathology of peri-implantitis is still not fully understood and there have been recent challenges to the consensus on its aetiology and pathology, especially in comparison with periodontitis. The assessment of biomarkers allows a comparison of the pathology of these diseases. The aim of this systematic review was to answer the research question: “Is there a difference in the biomarkers associated with peri-implantitis compared with periodontitis in adult humans?”

Methods

Electronic databases were searched and screened, and a manual search was also undertaken. The inclusion criteria were adults with peri-implantitis who had been compared to adults with periodontitis with the outcome of biomarkers assessed via biopsies or crevicular fluid samples in primary or secondary care settings, as recorded in case-control, case series and retrospective, prospective and cross-sectional observational studies. Two reviewers independently screened titles and abstracts and assessed full text articles for eligibility and inclusion. Both reviewers independently extracted data and assessed risk of bias. Differences in biomarker levels were the primary outcome and a narrative review was undertaken due to the heterogeneity of studies.

Results

In total, 2,374 articles were identified in the search, of which 111 full-text articles were assessed for eligibility and 13 were included in the qualitative synthesis. Five of the 13 included studies were deemed to be at high risk of bias, with the others having moderate risk. All studies were cross-sectional and performed at university hospitals. Nine of the 13 included studies found significant differences in the levels of biomarkers or their ratios between peri-implantitis and periodontitis. Four of the studies found no significant differences.

Conclusions

Within the limitations of the included studies, it appears that there may be a difference in biomarker levels and ratios between peri-implantitis and periodontitis, suggesting that these disease processes are somewhat distinct.

Does subgingival bacterial colonization differ between implants and teeth? A systematic review

The aim was of this study was to determine the current weight of evidence for the existence of specific differences between the microbiota of healthy teeth and healthy implants, or of teeth with periodontitis and implants with peri-implantitis. A systematic review was conducted according to the PRISMA statement. The MEDLINE, EMBASE and Cochrane databases were searched up to February 2018 for studies comparing microbiological data of biofilm samples collected from healthy teeth and implants or from teeth with periodontitis and implants with peri-implantitis. The weight of evidence was defined in three categories (strong, moderate and mild/some), according to the difference in number of studies showing statistically significantly higher counts and/or proportions and/or abundance and/or prevalence of microorganisms in health or in disease. Of the 132 articles identified, 8 were included. A wide range of microorganisms were present in different conditions but no microorganisms showed strong, moderate or mild/some evidence for a specific association with either teeth or implants. The results of this systematic review indicated that there is insufficient evidence in the literature to support specific differences between microorganisms colonizing teeth and implants, either in health or in disease.

Anaerobic Bacteria in Implants and Homologous Teeth 2-14 Years after Implantation

OBJECTIVE

The objective of the study was to establish whether there is a difference in the presence of potentially pathogenic anaerobic microorganisms around the implant and the homologous tooth in implant-prosthetic patients who received individual information about maintaining their oral hygiene.

MATERIAL AND METHODS

The study included 30 subjects with dental implants and metal-ceramic crowns. A periodontal probe was used to record the approximal plaque index (API), the papilla bleeding index (PBI), the periodontal pocket probing depth (PD) and the gingival recession. The fluid around the implant and the gingival sulcus fluid around the homologous tooth on the opposite lateral side were sampled.

RESULTS

The results have shown a positive API and PBI on 30% of the implants and a negative one on 70% of the implants. The average mucosal retraction measured around the implants was 0.15 mm, and the average probing depth was 2.25 mm. The API and PBI were positive on 78.3% of the homologous teeth. The average gingival retraction measured was 1.06 mm, and the average probing depth was 1.85 mm. Anaerobic bacteria were found in 12 out of 30 subjects (40%). Anaerobic bacteria were isolated only on the implant in 7 subjects, only on the homologous tooth in 3 subjects and both on the implant and the homologous tooth in 2 subjects.

CONCLUSIONS

Anaerobic bacteria were more abundantly present on implants than on homologous teeth.

Effects of Mechanical versus Manual Non Surgical Periodontal Therapy on Patient Comfort and Periodontal Healing: A Randomized Controlled Clinical Trial

Few studies have focused on the problem of pain and discomfort experienced during and after periodontal debridment. The aim of this study was to evaluate the effect of manual versus hand driven non surgical periodontal instrumentation on the patient's comfort, perception of pain and dental hypersensitivity during and after the instrumentation. Moreover, the influence of the treatment modality on the healing of slight to moderate periodontitis was assessed with careful attention to indices of periodontal inflammation. 22 subjects with a minimum of 4≥6mm periodontal pockets with 3 to 4mm attachment loss in different quadrants, the presence of ≥20 teeth with a minimum of four molars were enrolled. PD (probing depth, 6 sites per tooth), number of sites with PD> 6mm, buccal and lingual recessions were collected. Two quadrants Mouth Bleeding and Plaque Scores (T.M.P.S, T.M.B.S.) were assessed as the presence or absence of bleeding on probing and plaque following disclosing in quadrants 1–4 and 2–3. Non surgical periodontal treatment was delivered in two appointments performed within one week. In the first appointment the first and the fourth quadrants (patient's right side) were completely treated by mechanical or manual devices according to the randomization codes. In the second appointment the remaining two quadrants (patient's left side) were instrumented with the other therapeutical approach. The duration of each session, need for local anesthesia and additional information were recorded during the instrumentation appointments. All the patients were requested to fill in a form regarding pain, hypersensitivity, and need for painkillers following the two debridment appointments. Two drop outs were observed. Mean pain scores after treatment were higher in manual than in machine driven side (3.11±1.40 vs 2.33±1.41), whereas mean dentine hypersensitivity scores were slightly higher in mechanical side (4.40±1.56 vs 3.77±1.11). The need for painkillers after both treatment approaches was minimal. 6 out of 20 patients asked for local anesthesia and clustering regarding the request for both treated sides was observed. The mean instrumentation time was significantly lower for mechanical versus manual instrumentation (84.57±12.92 vs 119.25±13.50, p<0.001). Periodontal healing was similar in both the hand and machine driven instrumented sides. TMPS and TMBS were significantly lower at baseline compared to re-evaluation visits and the within group changes were significant lower at re-evaluation. Most of patients well tolerated non surgical periodontal treatment despite the type of instruments that are chosen by the clinician. Pain is infrequently reported and is more common after manual instrumentation compared to machine driven one. The need for local anesthesia is quite uncommon and is surely subject-dependent. Temporary, slight dentine hypersensitivity is a common adverse effect reported by most of patients after subgingival debridment. Machine driven debridment shows a dramatic advantage compared to manual treatment due to the lower amount of time needed to complete the instrumentation.

Biofilm related to dental implants

Oral biofilm-related diseases such as periodontal and peri-implant diseases are unique infections in that they develop from the resident indigenous microflora. As more implants are nowadays being placed, clinicians may encounter more complications. Therefore, understanding the etiology is warranted to establish adequate diagnosis and provide proper treatment. This article focuses on understanding peri-implant microbiology and its roles in peri-implant diseases.