Wim Teughels

Innovations in non-surgical periodontal therapy: Consensus Report of the Sixth European Workshop on Periodontology.

INTRODUCTION The remit of this working group was to update the existing knowledge base in non-surgical periodontal therapy. The published systematic reviews from the fourth EAP Workshop formed the starting point for this update and in addition specific innovations not covered in previous workshops were included. MATERIAL AND METHODS The literature was systematically searched and critically reviewed. Five manuscripts were produced in five specific topics identified as areas where innovative approaches have been developed in non-surgical periodontal therapy and which were deemed to be strategically important for patient care and clinical practice. RESULTS The results and conclusions of the review process are presented in the following papers, together with the group consensus statements, clinical implications and directions for future research: A systematic review of the effects of full mouth debridement with and without antiseptics in patients with chronic periodontitis. Advances in Power Driven Instrumentation. Laser application in non-surgical periodontal therapy - a systematic review. Antimicrobial therapy in periodontitis: the use of systemic antimicrobials against the subgingival biofilm. The cost-effectiveness of supportive periodontal-care for patients with chronic periodontitis.

Guiding Periodontal Pocket Recolonization: a Proof of Concept

The complexity of the periodontal microbiota resembles that of the gastro-intestinal tract, where infectious diseases are treatable via probiotics. In the oropharyngeal region, probiotic or replacement therapies have shown some benefit in the prevention of dental caries, otitis media, and pharyngitis, but their effectiveness in the treatment of periodontitis is unknown. Therefore, this study addressed the hypothesis that the application of selected beneficial bacteria, as an adjunct to scaling and root planing, would inhibit the periodontopathogen recolonization of periodontal pockets. Analysis of the data showed, in a beagle dog model, that when beneficial bacteria were applied in periodontal pockets adjunctively after root planing, subgingival recolonization of periodontopathogens was delayed and reduced, as was the degree of inflammation, at a clinically significant level. The study confirmed the hypothesis and provides a proof of concept for a guided pocket recolonization (GPR) approach in the treatment of periodontitis.

Do probiotics offer opportunities to manipulate the periodontal oral microbiota

BACKGROUND As in other fields of healthcare, probiotics have been introduced for prevention and treatment of periodontal diseases. OBJECTIVE This review was initiated to explore whether the use of probiotics can influence the periodontal microbiota and periodontal health. MATERIALS AND METHODS Literature on the mode of action of oral probiotics was reviewed and a systematic review was performed on the microbiological and clinical effects of oral probiotics on periodontal health. RESULTS Three animal and 11 in vivo human studies were retrieved. Six studies reported on microbiological effects whereas eight studies report on clinical effects. Seven studies were performed on healthy or gingivitis patients and four studies on periodontitis patients. Many of the retrieved studies are pilot in nature and with low quality. The high degree of heterogeneity between studies hampered analysis. CONCLUSION Taking into consideration all limitations, the currently available data indicate an effect of probiotics on the oral microbiota and a more limited effect on clinical periodontal outcome measures. However, there is an urgent need for properly conducted clinical trials where probiotics are used as adjuncts to standard periodontal care, similar to antibiotics, using probiotic strains with, at least at an in vitro level, proven periodontal probiotic effects.

Clinical and microbiological effects of Lactobacillus reuteri probiotics in the treatment of chronic periodontitis: a randomized placebo-controlled study.

Teughels W, Durukan A, Ozcelik O, Pauwels M, Quirynen M, Haytac MC. Clinical and microbiological effects of Lactobacillus reuteri probiotics in the treatment of chronic periodontitis: a randomized placebo-controlled study. J Clin Periodontol 2013; 40: 1025–1035. doi: 10.1111/jcpe.12155. AimThe aim of this randomized placebo-controlled clinical trial was to evaluate the effects of Lactobacillus reuteri-containing probiotic lozenges as an adjunct to scaling and root planing (SRP). Material and MethodsThirty chronic periodontitis patients were recruited and monitored clinically and microbiologically at baseline, 3, 6, 9 and 12 weeks after therapy. All patients received one-stage full-mouth disinfection and randomly assigned over a test (SRP + probiotic, n = 15) or control (SRP + placebo, n = 15) group. The lozenges were used two times a day for 12 weeks. ResultsAt week 12, all clinical parameters were significantly reduced in both groups, while there was significantly more pocket depth reduction (p < 0.05) and attachment gain (p < 0.05) in moderate and deep pockets; more Porphyromonas gingivalis reduction was observed in the SRP + probiotic group. ConclusionsThe results indicate that oral administration of L. reuteri lozenges could be a useful adjunct to SRP in chronic periodontitis.

Do oral biofilms influence the wear and corrosion behavior of titanium

The main aim of this work was to study the simultaneous wear-corrosion of titanium (Ti) in the presence of biofilms composed of Streptococcus mutans and Candida albicans. Both organisms were separately grown in specific growth media, and then mixed in a medium supplemented with a high sucrose concentration. Corrosion and tribocorrosion tests were performed after 48 h and 216 h of biofilm growth. Electrochemical corrosion tests indicated a decrease in the corrosion resistance of Ti in the presence of the biofilms although the TiO2 film presented the characteristics of a compact oxide film. While the open circuit potential of Ti indicated a tendency to corrosion in the presence of the biofilms, tribocorrosion tests revealed a low friction on biofilm covered Ti. The properties of the biofilms were similar to those of the lubricant agents used to decrease the wear rate of materials. However, the pH-lowering promoted by microbial species, can lead to corrosion of Ti-based oral rehabilitation systems.

Non‐surgical periodontal therapy with systemic antibiotics in patients with untreated aggressive periodontitis: a systematic review and meta‐analysis

OBJECTIVE The purpose of this meta-analysis is to evaluate the effectiveness of different systemic antibiotics in combination with scaling and root planing (SRP) compared to SRP alone in patients with untreated aggressive periodontitis. BACKGROUND In patients with aggressive periodontitis, SRP is often combined with the use of systemic antibiotics. However, the effectiveness of these antibiotics over time and differences in effectiveness between different antibiotics are hardly known. MATERIAL AND METHODS The MEDLINE-PubMed database was searched from their earliest records until January 20, 2014. Several journals were hand searched and some authors were contacted for additional information. The following outcome measures were analysed: mean probing pocket depth reduction, mean clinical attachment level gain and mean bleeding on probing change. Extracted data were pooled using a random effect model. Weighted mean differences were calculated and heterogeneity was assessed. RESULTS The search yielded 296 abstracts. Ultimately, 101 articles were selected of which 14 articles met the eligibility criteria. Systemic antibiotics showed a significant (p < 0.05) additional pocket depth reduction for moderate (0.36 ± 0.22 mm at 3 mo, 6 mo 0.42 ± 0.22 mm and 12 mo 0.88 ± 0.27 mm) and deep pockets (0.74 ± 0.36 mm at 3 mo, 6 mo 0.85 ± 0.55 mm and 12 mo 1.26 ± 0.81 mm) and a significant clinical attachment gain for moderate (0.26 ± 0.18 at 3 mo, 6 mo 0.52 ± 0.15 and 12 mo 0.83 ± 0.38) and deep pockets (0.59 ± 0.18 at 3 mo, 0.96 ± 0.21 at 6 mo and 1.00 ± 0.80 at 12 mo). CONCLUSION For the treatment of patients with aggressive periodontitis, systemic antibiotics combined with non-surgical periodontal therapy resulted in a significant additional effect compared to non-surgical therapy alone. There is a visible trend that showed metronidazole + amoxicillin is the most potent antibiotic combination.

Critical horizontal dimensions of interproximal and buccal bone around implants for optimal aesthetic outcomes: a systematic review

OBJECTIVE This systematic review was initiated to explore the critical horizontal interproximal and buccal bone dimensions around implants for an optimal aesthetic outcome. MATERIALS AND METHODS Pubmed, the Cochrane and the ISI web of Science databases were searched to identify eligible human studies that reflect on the aesthetic outcome of implants in relation to the thickness of the buccal bone after osteotomy preparation, and in relation to the tooth-to-implant or interimplant distance. Vertical bone dimensions were not considered. RESULTS AND DISCUSSION Articles relating horizontal buccal bone dimensions to aesthetic outcome could not be retrieved. The relation between horizontal buccal bone dimensions and vertical bone resorption could also not be confirmed. In relation to horizontal interproximal bone dimensions, some uniformity was detected among the limited number of articles. CONCLUSIONS Interproximally, a 3 mm interelement distance seems to result more frequently in an adequate papillary fill. In the bucco-oral direction, there is insufficient evidence to set a threshold for minimal buccal bone thickness to ensure an optimal aesthetic outcome. Many additional factors appear to be of importance and interact with each other.

Accuracy of computer‐aided implant placement

AIM To assess the accuracy of static computer-guided implant placement. MATERIAL AND METHODS Electronic and manual literature searches were conducted to collect information on the accuracy of static computer-guided implant placement and meta-regression analyses were performed to summarize and analyse the overall accuracy. The latter included a search for correlations between factors such as: support (teeth/mucosa/bone), number of templates, use of fixation pins, jaw, template production, guiding system, guided implant placement. RESULTS Nineteen accuracy studies met the inclusion criteria. Meta analysis revealed a mean error of 0.99 mm (ranging from 0 to 6.5 mm) at the entry point and of 1.24 mm (ranging from 0 to 6.9 mm) at the apex. The mean angular deviation was 3.81° (ranging from 0 to 24.9°). Significant differences for all deviation parameters was found for implant-guided placement compared to placement without guidance. Number of templates used was significant, influencing the apical and angular deviation in favour for the single template. Study design and jaw location had no significant effect. Less deviation was found when more fixation pins were used (significant for entry). CONCLUSION Computer-guided implant placement can be accurate, but significant deviations have to be taken into account. Randomized studies are needed to analyse the impact of individual parameters in order to allow optimization of this technique. Moreover, a clear overview on indications and benefits would help the clinicians to find the right candidates.

Is secondary caries with composites a material-based problem?

OBJECTIVE Secondary caries (SC) is one of the most important reasons for the failure of composite restorations, and thus has wide-reaching implications for the longevity of affected teeth and the health expenditure. Yet, it is currently not known whether secondary caries with composites is a material-based problem. The objective was to review literature with regard to SC around composite restorations to obtain better insights in the mechanisms behind SC with composites. METHODS Using Pubmed and Medline, international literature was searched for all articles about the clinical diagnosis, incidence and prevalence, histopathology and factors involved in the onset and development of SC around composite restorations. Additional studies were included after checking the reference lists of included papers. RESULTS SC with composites is to some extent associated to the restorative material, as significantly more caries occurred with composites than with amalgam. On the other hand, the class of the composite restoration (class V versus others and class I versus class II) was also determining for the development of SC, suggesting also other influencing factors than the material itself. The mechanisms behind the development of SC are much less clear and are most probably multifactorial. Even though the role of gaps an microleakage is questioned by some researchers, there are also indications that interfacial failure may play a role. Interfacial gaps larger than 60 μm seem to predispose interfacial demineralization, and may thus lead to caries. The question is therefore whether such interfacial gaps occur clinically? Initially, a gap may originate through polymerization shrinkage and through failure to obtain a good bond. Higher incidences of SC are observed in practice-based than in university-based studies, which may be attributed to different caries risk profiles of the included patients, or to the technique-sensitive placement procedure of composites. More research is necessary to investigate whether large gaps may arise through degradation processes. Apart from these factors, composites also seem to favor the growth of cariogenic bacteria on their surface, which has been associated with specific surface properties, release of components and lack of antibacterial properties. SIGNIFICANCE Current literature suggests that the restorative material might influence the development of secondary caries in different ways. However, it should be emphasized that patient-related factors remain the most important determinant of secondary caries.

Corrosion behaviour of titanium in the presence of Streptococcus mutans

OBJECTIVE The main aim of this in vitro study was to evaluate the influence of Streptococcus mutans on the corrosion of titanium. METHODS S. mutans biofilms were formed on commercially pure titanium (CP-Ti) square samples (10mm×10mm×1mm) using a culture medium enriched with sucrose. Open circuit potential (OCP) and electrochemical impedance spectroscopy (EIS) measurements were used to evaluate the corrosion behaviour of CP-Ti in the presence of S. mutans in Fusayamas artificial saliva. The corrosion of biofilm-free CP-Ti samples was also evaluated in artificial saliva. Biofilms biomass was measured by spectrophotometry, using crystal violet staining, after 1, 2 and 7 days. RESULTS The OCP values recorded on CP-Ti in the presence of S. mutans (-0.3±0.02V vs. SCE) was lower than those on biofilm-free CP-Ti (-0.1±0.01V vs. SCE) after 2h of immersion in artificial saliva (p<0.05). That reveals a high reactivity of titanium in presence of S. mutans. Impedance spectra revealed the formation of a compact passive film on titanium in artificial saliva or in the presence of a 2 days old S. mutans biofilm even though the corrosion resistance of CP-Ti has decreased in presence of a S. mutans biofilm. CONCLUSION The presence of bacterial colonies, such as S. mutans, negatively affected the corrosion resistance of the titanium.