Microbiological response to mechanical treatment in combination with adjunctive therapy. A review of the literature

Supra and subgingival application of antiseptics or antibiotics during periodontal therapy

Periodontal diseases (gingivitis and periodontitis) are characterized by inflammatory processes which arise as a result of disruption of the balance in the oral ecosystem. According to the current S3 level clinical practice guidelines, therapy of patients with periodontitis involves a stepwise approach that includes the control of the patient's risk factors and the debridement of supra and subgingival biofilm. This debridement can be performed with or without the use of some adjuvant therapies, including physical or chemical agents, host modulating agents, subgingivally locally delivered antimicrobials, or systemic antimicrobials. Therefore, the main aim of this article is to review in a narrative manner the existing literature regarding the adjuvant application of local agents, either subgingivally delivered antibiotics and antiseptics or supragingivally applied rinses and dentifrices, during the different steps in periodontal therapy performed in Europe.

In Vitro Preventive Effect and Mechanism of Action of Weissella cibaria CMU against Streptococcus mutans Biofilm Formation and Periodontal Pathogens

In this study, we evaluated the in vitro anti-biofilm, antibacterial, and anti-inflammatory activity of Weissella cibaria CMU (CMU), an oral probiotic, against periodontopathogens. Compared to other oral probiotics, CMU showed a superior inhibitory effect on the biofilm formation and growth of Streptococcus mutans on orthodontic wires and artificial teeth (p < 0.05). CMU exerted potent antibacterial effects against S. mutans and Porphyromonas gingivalis according to a line test. In human gingival fibroblasts (HGFs) stimulated by P. gingivalis, Fusobacterium nucleatum, or Prevotella intermedia, CMU suppressed the gene expression of pro-inflammatory cytokines [interleukin (IL)-6, IL-1β, IL-8, and tumor necrosis factor-α] in a dose-dependent manner (p < 0.05). CMU restored the production of the tissue inhibitor of metalloproteinase-1 following its inhibition by P. gingivalis, and it suppressed the expression of matrix metalloproteinase (MMP)-1 and -3 induced by periodontopathogens (p < 0.05). Moreover, CMU needed direct contact with HGFs to exert their anti-inflammatory function, indicating that they act directly on gingival cells to modulate local inflammation. Our preclinical study provides evidence for the potential benefits of topical CMU treatments in preventing the development of caries and periodontitis caused by the dysbiosis of the dental plaque microbiome.

Antioxidant effect of spirulina in chronic periodontitis

BACKGROUND

Production of reactive oxygen species (ROS) by polymorpho nuclear neutrophils occurs in chronic periodontitis. These ROS are mainly involved in bacterial destruction. However, extracellular release of same results in destruction of surrounding tissue. Spirulina, a potent antioxidant when administered sub gingivally in pockets can offer improved results in chronic periodontitis patients. This study was conducted to evaluate the effect of Spirulina when delivered sub gingivally in patients with chronic periodontitis.

METHODS

Sixty chronic periodontitis patients were divided into 2 groups. Group I (n = 30) were treated with Scaling and Root planning (SRP) followed by placement of placebo (SRP-P) and in Group II (n = 30) Spirulina microspheres were placed sub gingivally (SRP-S) following SRP. Clinical parameters like bleeding on probing (BOP), clinical attachment level (CAL), gingival index (GI) and probing pocket depth (PPD) were evaluated. Levels of salivary and serum Malondialdehyde (MDA) were estimated using ultra violet spectrophotometer.

RESULTS

At baseline, in both groups there was no statistically significant difference in clinical and biochemical parameters. Intra group comparisons of parameters from baseline to 90 days were statistically significant in both groups. After 90 days difference in clinical parameters and salivary MDA levels were statistically significant in SRP-S compared to SRP-P group. Though serum MDA levels were reduced in both groups, they were not significant statistically.

CONCLUSIONS

Our study concluded that, local drug delivery of Spirulina adjunctive to SRP has potent antioxidant effect in treatment of chronic periodontitis.

Plasma treatment effects on destruction and recovery of Porphyromonas gingivalis biofilms

The objective of this study was to investigate the treatment effects of non-thermal atmospheric gas plasmas (NTAP) on destruction and the recovery (or re-colonization) of Porphyromonas gingivalis (P. gingivalis) in biofilms. P. gingivalis is a well-known keystone periodontal pathogen strongly associated with periodontal diseases, especially periodontitis. P. gingivalis biofilms were formed on stainless steel coupons and treated for 1, 2, and 5 minutes by NTAP of pure argon gas and argon+oxygen gas mixture. MTT assay, colony forming unit (CFU) counting assay and confocal laser scanning microscopy (CLSM) were used to assess the destruction efficiency. In addition, the plasma treated biofilms were re-cultured in the medium supplemented with antibiotics and oxidative stress sources to determine the synergy of the NTAP with other antimicrobial agents. The results showed the plasma treatment could result in 2.7 log unit reduction in bacterial load. The recovered biofilm CFU with NTAP treatment combined with sub minimal inhibition concentration of amoxicillin was 0.33 log units less than the biofilm treated with amoxicillin alone. The recovered biofilm CFU in NTAP groups was about 2.0 log units less than that in the untreated controls under H₂O₂ treatment. There was approximately 1.0 log unit reduction of biofilm CFU in plasma treated biofilm compared with untreated control under paraquat treatment. The plasma treated biofilms exhibited less resistance to amoxicillin and greater susceptibility to hydrogen peroxide (H₂O₂) and paraquat, suggesting that NTAP may enhance biofilm susceptibility to host defense. These in vitro findings suggested that NTAP could be a novel and effective treatment method of oral biofilms that cause periodontal diseases.

Effectiveness of Chlorhexidine and Metronidazole Gels in the management of gingivitis. A clinical trial

Objectives:

The purpose of the present study was to compare the topical application of chlorohexidine (CHX) and Metronidazole (MTZ) gels, individually and in combination in patients with gingivitis for up to 12 weeks follow-up.

Methods:

The clinical trial was conducted at Liaquat University of Medical Health Sciences (LUMHS) Jamshoro and Hyderabad, Institute of Dentistry from 1^st March 2019 to 1^st March 2020. Patients were selected based on inclusion criteria. Out of 125 screened patients, ninety-nine patients agreed to participate in the study. At the beginning of study all patients were assessed for gingival inflammation by using gingival index (GI) (Loe and silness, 1963). Scaling root planning (SRP) was performed in all patients. Subjects were randomly selected in three groups (n=33 each). In Group-A CHX gel was applied, Group-B Metronidazole gel was applied and the combination of two was applied to patients of Group-C. Patient follow up was done and gingival parameters were assessed at baseline, fourth week and twelve weeks. Apart from the clinical evaluation, a subjective evaluation was also undertaken. Significance level of 0.05 and a desired study power of at least 80% was estimated. Analysis of Variance (ANOVA) test for comparison was used within groups.

Results:

A significant improvement in gingival scores was noted in all groups from baseline. At 4 weeks CHX (1.25±0.21) MTZ (1.81±0.38) CHX+MTZ (1.29±0.34) compared to baseline CHX (2.77±0.24) MTZ (2.84±0.54) CHX+MTZ (2.74±0.31) demonstrated substantial improvement (p<0.001). However, gingival scores showed inclination at 12 weeks CHX (1.18±0.41) MTZ (1.21±0.48) CHX+MTZ (1.11±0.14) with no significant difference to week 4 (p>0.001).

Conclusion:

Local MTZ gel and MTZ+CHX gel showed effectiveness similar to CHX gel application adjunct to scaling and root planning in the treatment of gingivitis.

A Versatile Biocompatible Antibiotic Delivery System Based on Self-Assembling Peptides with Antimicrobial and Regenerative Potential

Periodontitis is a chronic inflammatory and tissue-destructive disease. Since the polymicrobiome in the oral cavity makes it difficult to treat, novel therapeutic strategies are required. Hydrogels based on self-assembling peptides (SAP) can be suitable candidates for periodontal therapy due to their injectability, biocompatibility, cargo-loading capacity, and tunable physicochemical and mechanical properties. In this study, two SAP hydrogels (P11-4 and P11-28/29) are examined for their intrinsic antimicrobial activity, regenerative potential, and antibiotic delivery capacity. A significant antibacterial effect of P11-28/29 hydrogels on the periodontal pathogen Porphyromonas gingivalis and a less pronounced effect for P11-4 hydrogels is demonstrated. The metabolic activity rates of human dental follicle stem cells (DFSCs), which reflect cell viability and may thus indicate the regenerative capacity, are similar on tissue culture polystyrene (TCPS) and on P11-4 hydrogels after 14 days of culture. Noticeably, both SAP hydrogels strengthen the osteogenic differentiation of DFSCs compared with TCPS. The incorporation of tetracycline, ciprofloxacin, and doxycycline does not affect fibril formation of either SAP hydrogel and results in favorable release kinetics up to 120 h. In summary, this study reveals that P11-SAP hydrogels combine many favorable properties required to make them applicable as prospective novel treatment strategy for periodontal therapy.

Combination of Zinc Hyaluronate and Metronidazole in a Lipid-Based Drug Delivery System for the Treatment of Periodontitis

BACKGROUND

Despite being a highly prevalent disease and a possible contributor to adult tooth loss, periodontitis possesses no well-established therapy. The aim of the recent study was the development and evaluation of a mucoadhesive monophase lipid formulation for the sustained local delivery of amoxicillin, metronidazole, and/or zinc hyaluronate or gluconate.

METHODS

To investigate our formulations, differential scanning calorimetry, X-ray diffraction, swelling, erosion, mucoadhesivity, drug release, and antimicrobial measurements were performed.

RESULTS

Differential scanning calorimetry (DSC) and X-ray diffraction (XRD) results show that the loaded drugs are in a suspended form, the softening of the formulations starts at body temperature, but a part remains solid, providing sustained release. Swelling of the lipid compositions is affected by the hydrophilic components, their concentration, and the strength of the coherent lipid structure, while their erosion is impacted by the emulsification of melted lipid components.

CONCLUSIONS

Results of drug release and antimicrobial effectiveness measurements show that a sustained release may be obtained. Amoxicillin had higher effectiveness against oral pathogens than metronidazole or zinc hyaluronate alone, but the combination of the two latter could provide similar effectiveness to amoxicillin. The applied mucoadhesive polymer may affect adhesivity, drug release through the swelling mechanism, and antimicrobial effect as well.

Microbiological dynamics of red complex bacteria following full-mouth air polishing in periodontally healthy subjects-a randomized clinical pilot study

OBJECTIVES

Suppression of periodontal pathogens in the oral cavity of periodontally healthy individuals may lower the risk for periodontal or periimplant diseases. Therefore, the present study aimed to analyze the effect of supragingival debridement (SD) with adjunctive full mouth glycine powder air polishing (FM-GPAP) on the prevalence of periodontal pathogens in periodontally healthy individuals.

MATERIALS AND METHODS

Eighty-seven systemically and periodontally healthy intraoral carriers of red complex bacteria, i.e., Porphyromonas gingivalis, Tannerella forsythia, and Treponema denticola or other periodontal pathogens including Aggregatibacter actinomycetemcomitans, Prevotella intermedia, and Eikenella corrodens were enrolled into the study and randomly assigned to receive SD with adjunctive FM-GPAP (test, n = 42) or SD alone (control, n = 45). In the first observation period, microbiological samples were obtained prior to, and 2, 5, and 9 days following intervention. If one of these periodontal pathogens could still not be identified, additional microbial sampling was performed after 6 and 12 weeks.

RESULTS

The prevalence of red complex bacteria was significantly reduced in the test compared to the control group following treatment (p = 0.004) and at day 9 (p = 0.031). Intragroup comparison showed a significant (test, p < 0.001; control, p ≤ 0.01) reduction in the mean prevalence in both groups from BL through day 9 with an additional significant intergroup difference (p = 0.048) at day 9. However, the initial strong reduction returned to baseline values after 6 and 12 weeks.

CONCLUSION

In periodontally healthy carriers of periodontal pathogens, FM-GPAP as an adjunct to SD transiently enhances the suppression of red complex bacteria.

CLINICAL RELEVANCE

Whether the enhanced suppression of red complex bacteria by adjunctive FM-GPAP prevents the development of periodontitis in periodontally healthy carriers requires further investigations.

Evaluating the effectiveness of clarithromycin as an adjunct to scaling and root planing: A randomized clinical trial

Background

Administration of systemic antibiotics may implement persuasive treatment effect for chronic periodontitis by intending tissue-invasive bacteria in addition to accustomed nonsurgical periodontal therapy (NSPT).

Aims

The aim of this study was to assess the ancillary effects of oral clarithromycin (CLM) along with NSPT for chronic periodontitis.

Materials and Methods

Thirty periodontitis patients were randomly divided into two equal groups in this double-blind, randomized, parallel group, and active-controlled trial: test group - scaling and root planning (SRP) plus CLM (500 mg thrice daily for 7 days, orally) was given, and control group - only SRP was done. Clinical analysis, such as gingival index (GI), probing depth (PD), and clinical attachment loss (CAL), were taken at baseline, 3 months, and 6-month intervals for both groups. Subgingival plaque samples were cultured for periodontopathic organisms. Immunological parameter C-reactive protein (CRP) levels were estimated.

Results

SPSS version 14 was used for statistical analysis. The intragroup comparison showed a significant reduction in the mean scores of all the parameters from baseline to 6 months. The intergroup comparison showed a statistically significant reduction of PD from baseline to 3 months (P < 0.001). GI, CAL, and CRP levels were also reduced but not statistically significant. The mean colony-forming units (CFU) of Aggregatibacter actinomycetemcomitans (Aa) and Porphyromonas gingivalis (Pg) showed a statistically significant reduction from baseline to 3 months only in the test group (P = 0.042) and (P = 0.046), respectively. There was no statistically significant reduction of Aa and Pg at 6 months.

Conclusions

CLM conceivably accepted as an addendum to NSPT for a shorter period.

Hyaluronic Acid and Periodontitis

Hyaluronic acid (HA; synonyms- Hyaluronan, Hyaluronate) is a glycosaminoglycan found in the connective tissue of vertebrates. It is the most abundant glycosaminoglycan of higher molecular weight in the extracellular matrix of soft periodontal tissues. The use of HA in the treatment of inflammatory process is established in medical areas such as orthopedics, dermatology and ophthalmology. In the field of dentistry, it has shown anti-inflammatory and anti-bacterial effects in gingivitis and periodontitis therapy. Due to its tissue healing properties, it could be used as an adjunct to mechanical therapy in the treatment of periodontitis.

Effect of 1.2% of simvastatin gel as a local drug delivery system on Gingival Crevicular Fluid interleukin-6 & interleukin-8 levels in non surgical treatment of chronic periodontitis patients

AIM

The present study was carried out to evaluate the effect of 1.2% simvastatin gel as local drug delivery (LDD) system on Gingival Crevicular Fluid (GCF) Interleukin -6 (IL-6) and Interleukin-8 (IL-8) levels in chronic periodontitis patients, in addition to scaling and root planing (SRP).

METHODS

A total of 46 chronic periodontitis patients were equally divided into two groups. Group I patients were treated by SRP; Group II patients were treated by SRP followed by LDD of 1.2% simvastatin (SMV) gel. Plaque index (PI), Gingival index(GI), Sulcus Bleeding Index (SBI), Probing pocket depth (PPD) and Relative clinical attachment level (CAL) were recorded & GCF samples were collected at baseline (0day) and at 45th day from both the groups. The collected GCF samples were analysed for IL-6 and IL-8 levels with enzyme-linked immunosorbent assay (ELISA).

RESULTS

Both the groups showed significant reduction in all the clinical parameters scores and IL-6 and IL-8 levels after non-surgical periodontal therapy (SRP for group I/SRP+1.2% SMV gel for group II) in contrast to baseline values. However, a greater reduction was observed in group II. A non-significant positive correlation was observed between clinical parameters and IL-6 and IL-8 levels except at baseline, a significant correlation was observed between PPD &IL 6 levels in group II.

CONCLUSIONS

In adjunct to SRP, 1.2% Simvastatin gel acts as an effective local drug delivery agent for the management of chronic periodontitis.

Efficacy of Photodynamic Therapy and Lasers as an Adjunct to Scaling and Root Planing in the Treatment of Aggressive Periodontitis - A Clinical and Microbiologic Short Term Study

INTRODUCTION

Aggressive periodontitis comprises a group of rare, severe, rapidly progressive form of periodontitis. Conventional treatment includes mechanical debridement augmented with adjunctive antimicrobial therapy. Development of antibiotic resistance has led to use of lasers. Photodynamic therapy (PDT) is a novel non-invasive therapeutic approach with increased site and pathogen specificity. This study compares PDT and Lasers as an adjunct to conventional Scaling in the treatment of patients with aggressive periodontitis.

MATERIALS AND METHODS

Fifteen untreated aggressive periodo-ntitis patients were randomly assigned in a split mouth design for one of the following treatment modalities: 1) SRP alone; (2) SRP + Diode Laser irradiation with 810 nm at 1W, continuous mode for 30 sec per tooth; (3) SRP + PDT on "0" day; (4) SRP + PDT on "0", 7(th) and 21(st) day. The clinical parameters included PI, BOP, PPD, CAL recorded at the baseline & 3(rd) month. The site with greatest probing pocket depth (PPD) was selected from each quadrant for bacterial sampling and cultured for Aggregatibacter actinomycetemcomitans and Porphyromonas gingivalis & Prevotella intermedia.

RESULTS

Statistically significant reduction in clinical & microbial parameters was seen. Sites 4 showed a greater reduction compared to other groups.

CONCLUSION

Photodynamic therapy is a valuable treatment modality adjunctive to conventional scaling and root planing.

Effect of topical simvastatin (1.2 mg) on gingival crevicular fluid interleukin-6, interleukin-8 and interleukin-10 levels in chronic periodontitis - A clinicobiochemical study

OBJECTIVES

The impact of simvastatin (SMV), a cholesterol lowering drug, on bone metabolism appears to involve complex interaction with cholesterol metabolites, hormones, inflammatory mediators and growth factors, thus having direct influence on extent and severity of periodontitis. The present study aims to evaluate the in vivo effect of subgingivally delivered SMV gel (1.2 mg) as a local drug-delivery agent on clinical parameters and on interleukin-6 (IL-6), interleukin-8 (IL-8) and interleukin-10 (IL-10) levels in gingival crevicular fluid (GCF) of chronic periodontitis patients.

MATERIALS AND METHODS

50 patients were selected and categorized into two treatment groups: control (scaling and root planing) and test group (scaling and root planing with SMV gel). At initial appointment, clinical parameters were measured. Biochemical analysis of GCF samples was done to evaluate the amount of IL-6, IL-8 and IL-10. GCF sampling and clinical parameters were repeated at one and three months for both the groups.

RESULTS

SMV has an inhibitory effect on pro-inflammatory cytokines (IL-6, IL-8) and stimulatory effect on anti-inflammatory cytokines (IL-10) in GCF of periodontitis patients and has significantly positive effect on all clinical parameters except relative attachment level (RAL). The addition of SMV, thereby, further alters the levels of cytokine that reflect enhanced antibacterial host defence activity at that site.

CONCLUSION

Topical SMV has a beneficial effect on periodontal health. Removal of the bacterial plaque and subgingival delivery of SMV significantly modulates the chemokines present in GCF. To summarize, SMV shows promising role in the management of periodontitis.

Comparative evaluation of the efficacy of curcumin gel with and without photo activation as an adjunct to scaling and root planing in the treatment of chronic periodontitis: A split mouth clinical and microbiological study

Aims and Objectives:

Harnessing Mother Nature's bountiful remedies for rejuvenation has been in vogue since time immemorial. Turmeric contains the polyphenol Curcumin in its rhizome. It produces reactive oxygen species (ROS) with visible light irradiation as photodynamic therapy (PDT) - which validates its use in the treatment of periodontitis. This study compares Curcumin and Curcumin PDT as an adjunct to conventional Scaling and Root Planing (SRP) with SRP alone in the treatment of patients with chronic periodontitis.

Materials and Methods:

Sixty sites in fifteen untreated chronic periodontitis patients were randomly assigned in a split mouth design for one of the treatment modalities; 1) Scaling and root planing (SRP) alone, (2) SRP + Curcumin application for 5 min, (3) SRP + Curcumin application for 5 min + irradiation with blue light emitting diode of wavelength 470 nm for 5 min. (Curcumin PDT) on 0 day.(4) SRP + Curcumin PDT on “0”, 7^th and 21^st day. The clinical parameters included plaque index (PI), bleeding on probing (BOP) measured by sulcus bleeding index (SBI), probing pocket depth (PPD), clinical attachment level (CAL) recorded at the baseline & 3^rd month. The site with greatest probing pocket depth (PPD) was selected from each quadrant for bacterial sampling and culturing for Aggregatibacter actinomycetemcomitans (Aa) and other black pigment producing microorganisms (BPB) like Porphyromonas gingivalis & Prevotella intermedia.

Conclusion:

The present study showed that Curcumin photodynamic therapy is a valuable treatment modality adjunctive to conventional scaling and root planing over Curcumin application. Moreover, multiple adjunctive applications of photodynamic therapy are more beneficial than single application in reducing clinical & microbiological parameters.

Diagnosis and anti-infective therapy of periodontitis

Periodontal diseases (gingivitis and periodontitis) are chronic bacterial infections with a remarkably high prevalence and morbidity. Periodontitis, in contrast to gingivitis, is not reversible, is associated with certain bacterial species and affects all of the soft tissue and bone that support teeth. Among the periodontal pathogens, species, such as Aggregatibacter (Actinobacillus) actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia, Tannerella forsythensis, and several forms of uncultivable spirochetes play the major role in the pathogenesis. In severe chronic, recurrent and especially aggressive forms of periodontitis, diagnosis of the species involved and, whenever possible, an optimized evidence-based antimicrobial treatment is indicated. In order to monitor alarming bacterial changes in the periodontal pocket, several techniques, namely microscopy, culture, immunoassays, enzyme tests and DNA-based techniques, have been established and the methods are described in the first part of this review. In the second part, the selection and use of locally delivered (topical) and systemic antibiotics used adjunctively in periodontal therapy are discussed.

Effect of ethylcellulose and propylene glycol on the controlled-release performance of glyceryl monooleate-mertronidazole periodontal gel

Controlled-release metronidazole, mucoadhesive gel proposed as a drug-delivery system for periodontal application was developed and characterized. The system was based on a mixture of glycerylmonooleate (GMO) and ethylcellulose (EC). The mechanism of release depends: firstly, on the ability of GMO to form a viscous liquid crystalline mesophases and secondly on the solubilized EC to form a hydrophobic network when the mixture comes into contact with water resulting in sustaining the release of the drug. Ethylcellulose dissolved in GMO had a profound influence on the rate of drug release, reduced the initial drug release and prolonged the sustained release of metronidazole. Propylene glycol (PG) was added to increase the solubility of the drug and water was added with PG to control the viscosity. A controlled release formulation containing w/w, 20% metronidazole, 10% PG, 5% water and 65% GMO that contains 7% EC was found to be mucoadhesive, easily injectable at room temperature, and to follow Fickian diffusion release mechanism. When the drug loading was increased the drug release was accelerated, and the mechanism followed anomalous controlled-release mechanism. Stability studies indicated that the formulation should be stored at 4 °C in a dark place.

Adjunctive effect of chlorhexidine antiseptics in mechanical periodontal treatment: first results of a preliminary case series

OBJECTIVES

The aim of the present case series was to evaluate the clinical and microbiological effects of a single session of mechanical and manual scaling and root planing (SRP) combined with the use of two different chlorhexidine formulations in the treatment for generalized chronic periodontitis.

METHODS

Ten patients affected by chronic periodontal disease with periodontal probing depth (PPD) ≥ 5 mm were treated with SRP plus local chlorhexidine. In each patient, similar teeth, treated with SRP with the adjunctive use of chlorhexidine digluconate and dihydrochloride or chlorhexidine gluconate, respectively, were selected and assigned to a test and a control group. In both groups, PPD, bleeding on probing (BOP) parameters, total bacterial counts (TBC) and quality of periodontal bacteria at time 0 and 6 weeks after treatment were measured.

RESULTS

PPD significantly decreased over time both in the test and in the control group; however, no significant differences between the two groups were observed. BOP and TBC were significantly lower in the test than in the control group 6 weeks after treatment. In the post-treatment revaluation, a significant decrease both in the treatment and in the control group, for each of the single periodontal pathogens, was observed.

CONCLUSION

In this study--a preliminary case series with small sample size and short follow-up--the adjunctive use of chlorhexidine (CHX) to SRP resulted in clinical and microbiological benefits in the treatment for generalized chronic periodontitis. A CHX gel formulation consisting of CHX digluconate and CHX dihydrochloride seems to lead some additional benefits over SRP plus CHX gluconate in the short term. Additional investigations are needed to evaluate the effectiveness of this antiseptic therapy.

Ultramorphology of the root surface subsequent to hand-ultrasonic simultaneous instrumentation during non-surgical periodontal treatments: an in vitro study

Objective

The purpose of this study was to investigate the ultramorphology of the root surfaces induced by mechanical instrumentation performed using conventional curettes or piezoelectric scalers when used single-handedly or with a combined technique.

Material and Methods

Thirty single-rooted teeth were selected and divided into 3 groups: Group A, instrumentation with curettes; Group B instrumentation with titanium nitride coated periodontal tip mounted in a piezoelectric handpiece; Group C, combined technique with curette/ultrasonic piezoelectric instrumentation. The specimens were processed and analyzed using confocal and scanning electron microscopy. Differences between the different groups of instrumentation were determined using Pearson’s χ ² with significance predetermined at α=0.001.

Results

Periodontal scaling and root planing performed with curettes, ultrasonic or combined instrumentation induced several morphological changes on the root surface. The curettes produced a compact and thick multilayered smear layer, while the morphology of the root surfaces after ultrasonic scaler treatment appeared irregular with few grooves and a thin smear layer. The combination of curette/ultrasonic instrumentation showed exposed root dentin tubules with a surface morphology characterized by the presence of very few grooves and slender remnants of smear layer which only partially covered the root dentin. In some cases, it was also possible to observe areas with exposed collagen fibrils.

Conclusion

The curette-ultrasonic simultaneous instrumentation may combine the beneficial effects of each instrument in a single technique creating a root surface relatively free from the physical barrier of smear layer and dentin tubules orifices partial occlusion.

Influence of compression force on the behavior of mucoadhesive buccal tablets

The purpose of this research was to study the compression force influence on polymers, tablet behavior and drug release rate. Several tablet batches were produced by varying the compression force and by using hydroxyethyl cellulose (HEC) and Carbopol 940 in the 1:1 ratio as matrix forming polymers. All batches were characterized by DSC and X-ray analyses and in terms of swelling, ex vivo and in vivo mucoadhesive time, ex vivo mucoadhesion force, and in vitro and in vivo release. No significant excipient-excipient or excipient-drug interactions were observed in any of the batches. All the tablets hydrated quickly and their high hydration percentage showed that the compression forces used did not remarkably affect the water penetration and the polymeric chain stretching. Mucoadhesion performances and drug release were mainly influenced by compression force; its increase produced higher ex vivo and in vivo mucoadhesion and the in vitro and in vivo drug releases were seen to decrease with the increase of the compression force. However tablets fabricated by using the lowest compression force showed the best in vivo mucoadhesive time and hydrated faster when compared to the others. Tablets 4 and 5, prepared with the highest forces, caused pain during in vivo application and gave rise to irritation needing to be detached by the volunteers while tablet 1, prepared with the lowest force, gave the best results because it was able to produce the highest drug salivary concentration and no pain. All tablets exhibited an anomalous release mechanism.

Antimicrobial Photodynamic Therapy in the Non-Surgical Treatment of Aggressive Periodontitis: A Preliminary Randomized Controlled Clinical Study

BACKGROUND

The treatment of aggressive periodontitis has always presented a challenge for clinicians, but there are no established protocols and guidelines for the efficient control of the disease.

METHODS

Ten patients with a clinical diagnosis of aggressive periodontitis were treated in a split-mouth design study to either photodynamic therapy (PDT) using a laser source with a wavelength of 690 nm associated with a phenothiazine photosensitizer or scaling and root planing (SRP) with hand instruments. Clinical assessment of plaque index (PI), gingival index (GI), bleeding on probing (BOP), probing depth (PD), gingival recession (GR), and relative clinical attachment level (RCAL) were made at baseline and 3 months after treatment with an automated periodontal probe.

RESULTS

Initially, the PI was 1.0 +/- 0.5 in both groups. At the 3-month evaluation, the plaque scores were reduced and remained low throughout the study. A significant reduction of GI and BOP occurred in both groups after 3 months (P <0.05). The mean PD decreased in the PDT group from 4.92 +/- 1.61 mm at baseline to 3.49 +/- 0.98 mm after 3 months (P <0.05) and in SRP group from 4.92 +/- 1.14 mm at baseline to 3.98 +/- 1.76 mm after 3 months (P <0.05). The mean RCAL decreased in the PDT group from 9.93 +/- 2.10 mm at baseline to 8.74 +/- 2.12 mm after 3 months (P <0.05), and in the SRP group, from 10.53 +/- 2.30 mm at baseline to 9.01 +/- 3.05 mm after 3 months.

CONCLUSION

PDT and SRP showed similar clinical results in the non-surgical treatment of aggressive periodontitis.

Effects of metronidazole plus amoxicillin as the only therapy on the microbiological and clinical parameters of untreated chronic periodontitis

AIM

To determine the effect of metronidazole plus amoxicillin (M+A) as the sole therapy, on the subgingival microbiota of chronic periodontitis.

MATERIAL AND METHODS

Twenty-two patients with untreated chronic periodontitis were randomly assigned to a group that received M+A for 7 days, or to a group receiving scaling and root planing (SRP) and two placebos. Clinical measurements including sites with plaque, bleeding on probing (BOP), probing depth (PD) and attachment level (AL) were made at baseline, 3, 6, 9 and 12 months. Subgingival plaque samples were taken from all teeth at baseline 3, 6, 9 and 12 months for the counts of 40 subgingival species using checkerboard DNA-DNA hybridization.

RESULTS

Mean PD was reduced from 2.80+/-0.45 at baseline to 1.95+/-0.05 at 12 months (P<0.001) and from 2.39+/-0.41 to 1.95+/-0.10 (P<0.001) in the M+A- and SRP-treated patients, respectively. Corresponding values for relative mean AL were 10.07+/-1.30-9.77+/-0.34 (P<0.001) and 9.94+/-0.28-9.77+/-0.26 (P<0.001). Percentage of sites exhibiting BOP were 40.6+/-18.3-14.0+/-1.4 (P<0.001), and 38.5+/-5.1-19.0+/-2.8 (P<0.001) in the M+A and SRP groups, respectively. Mean total DNA probe counts and counts of the majority of the 40 test species were significantly reduced over time in both groups, with no significant differences detected at any time point between groups. At 12 months many of the species were still present at significantly lowered levels compared with their baseline counts in both groups.

CONCLUSIONS

Changes in clinical and microbiological parameters were similar after receiving systemically administered M+A as the sole therapy or after receiving SRP only.

The effect of bee propolis on oral pathogens and human gingival fibroblasts

Propolis is one of the few natural remedies that have maintained its popularity over a long period of time. The aim of this study is to investigate the antimicrobial properties of six propolis solutions and evaluate their cytotoxicity on gingival fibroblasts at different dilutions. Two different solutions of powder propolis (Sigma) and Turkish propolis were prepared and propylene glycol (PG) and alcohol were used as solvents for each propolis sample. In addition to the four propolis solutions, two other propolis samples of far geographic regions (USA and Australia) were included in the study. The antibacterial effects of six solutions on oral pathogen microorganisms were tested and their cytotoxic effects on human gingival fibroblasts were evaluated by MTT assay. The effective dilutions of the six propolis samples on periodontopathogen microorganisms were found to be cytotoxic to gingival fibroblasts. All solutions had strong antifungal activity and the effective dilutions were safe for gingival fibroblasts. Propolis could have a promising role in the future medicine, if appropriate solutions can be prepared being strongly antibacterial and non-cytotoxic as well.

Efficacy of photodynamic therapy on inflammatory signs and two selected periodontopathogenic species in a beagle dog model

BACKGROUND

Current research aims to find alternatives to conventional methods for suppressing periodontopathogenic bacteria. Photodynamic therapy (PDT) could be a suitable treatment procedure of periodontal infections.

METHODS

In the present study, the PDT method was tested with two photosensitizers, chlorine e6 and BLC1010, in an experiment on beagle dogs. The animals were infected with Porphyromonas gingivalis (Pg) and Fusobacterium nucleatum (Fn) in all subgingival areas. After infection, we observed clinical signs of gingival inflammation, including an increase of redness and bleeding on probing. Microbiological monitoring before and after treatment was performed using polymerase chain reaction (PCR). PDT was conducted with a diode laser with a wavelength of 662 nm using a power of 0.5 W and the photosensitizers.

RESULTS

The PDT procedure carried out with either of the photosensitizers caused a significant reduction in the clinical inflammation signs of redness and BOP, compared to the controls (laser only and no treatment). Furthermore, PDT with chlorine e6 caused a significant reduction in P. gingivalis-infected sites, whereas there was a lack in suppression after PDT with BLC1010. F. nucleatum could hardly be reduced with chlorine e6, and only to a certain extent with BLC 1010 and laser only. In the control groups, the Pg-infected test sites did not change.

CONCLUSIONS

This study demonstrated that the photodynamic therapy using photosensitizer and a 662 nm laser light source is distinctly advantageous in reducing the periodontal signs of redness and bleeding on probing. The procedure also appears to significantly suppress P. gingivalis.

The Impact of Periodontal Therapy and the Adjunctive Effect of Antiseptics on Breath Odor-Related Outcome Variables: A Double-Blind Randomized Study

BACKGROUND

Bad breath is often caused by periodontitis and/or tongue coating. This study followed the impact of initial periodontal therapy on several halitosis-related outcome variables over a 6-month period. Organoleptic ratings are often uncomfortable for the patient and have several disadvantages. They are, for instance, influenced by external parameters (e.g., food intake and cosmetics) and need to be calibrated among researchers worldwide. A second aim was to evaluate the reliability of saliva incubation as an in vitro indirect test for breath recording.

METHODS

In this double-blind, randomized, medium-term, parallel study 45 moderate periodontitis patients without obvious tongue coating were enrolled. Besides a one-stage, full-mouth disinfection and oral hygiene improvement (including daily tongue scraping), patients were instructed to rinse daily for 6 months with one of the following products (randomly allocated): chlorhexidine (CHX) 0.2% + alcohol, CHX 0.05% + cetyl pyridinium chloride (CPC) 0.05% without alcohol (a new formulation), or a placebo solution. At baseline and 3 and 6 months, a series of parameters were recorded including: concentration of volatile sulfide compounds (VSC), tongue coating, and an estimation of the microbial load (at anterior and posterior parts of the tongue, saliva, dental plaque). The intraoral VSC ratings were compared to in vitro VSC recordings and organoleptic evaluations of the headspace air from 1 and 2 hours incubated saliva (0.5 ml, 37 degrees C, anaerobic chamber).

RESULTS

Even though the initial VSC values were not high (+/-90 ppb with only 18 patients revealing more than 100 ppb), significant (P <0.05) reductions could be achieved in the CHX and CHX + CPC group, and to a lower extent in the placebo group (P = 0.10). Tongue scraping resulted in a significant reduction (P < or =0.05) of the tongue coating up to month 6 in the placebo and CHX + CPC group, but not in the CHX group (confusion due to staining). The CHX and CHX + CPC group showed, in comparison to baseline, significant (P <0.001) reductions in the number of anaerobic species in the supragingival plaque, in the saliva, and on the anterior part of the tongue. For the posterior part of the tongue the microbial changes remained < or =0.3 log values (P >0.05). For the placebo group, the microbial changes never reached a level of significance (< or =0.3 log values). A strong correlation was found between the intraoral VSC ratings and the 1-hour (r = 0.48, P <0.0001; r = 0.54, P = 0.0003 for baseline data only) and 2-hour (r = 0.43, P <0.0001) VSC production of incubated saliva. The latter also correlated very strongly (r = 0.71) with the number of anaerobic species in the saliva. The VSC values and organoleptic ratings of the incubated saliva also correlated strongly with each other (r = 0.64 for 1-hour and 0.73 for 2-hour incubation).

CONCLUSIONS

The results of this study indicate that in patients with moderate periodontitis, initial periodontal therapy including tongue scraping did not have a significant effect on the microbial load of the tongue and had only a weak impact on the VSC level, except when combined with a mouthrinse. Saliva incubation can be used as an indirect way to score breath odor. It offers simplicity, objectivity, and is less invasive.

A 0.05% cetyl pyridinium chloride/0.05% chlorhexidine mouth rinse during maintenance phase after initial periodontal therapy

BACKGROUND

Chlorhexidine (CHX) mouth rinse/spray can still be considered the gold standard in the chemical prevention of plaque formation and development of gingivitis. The product unfortunately has some side effects, such as extrinsic tooth staining, poor taste, taste disturbance, sensitivity changes in tongue, pain and irritation because of the alcohol content. These side effects led to the search of new formulations.

METHODS

In this double-blind, randomized, long-term, parallel study, 48 moderate periodontitis patients rinsed for 6 months (starting immediately after a "one-stage, full-mouth" disinfection) with one of the following products: CHX 0.2%+alcohol (Corsodyl), CHX 0.05%+ cetyl pyridinium chloride (CPC) 0.05% and no alcohol (Perio-Aid Maintenance, a new formulation), or the placebo of the latter. After 1, 3 and 6 months a series of clinical and microbiological parameters were recorded for the supra- and subgingival area as well as for saliva.

RESULTS

Although there was a significant treatment impact (mechanical debridement) in all groups, both CHX solutions further decreased both plaque and gingivitis indices (p<0.001 and p<0.05, respectively), when compared with placebo. This was also reflected by additional reductions in the number of CFU/ml of aerobic and especially anaerobic species and by a suppression of Streptococcus mutans (versus an overgrowth for the placebo), in all niches. Differences between both CHX solutions were never encountered. The subjective ratings were slightly in favour of the new CHX-CPC formulation when compared with the other CHX-alcohol formulation, especially for taste of the product (p<0.05), but less impressive for the staining of teeth and tongue.

CONCLUSIONS

The results of this study demonstrated the potential of a new CHX 0.05%+CPC 0.05% non-alcoholic formulation as an effective antiplaque agent for long-term use with reduced subjective side effects.

Serum and gingival crevicular fluid levels of ciprofloxacin in patients with periodontitis

BACKGROUND

The use of antibiotics as an adjunctive therapy in the treatment of periodontal diseases is of special interest to dental practitioners. In addition to using an appropriate antibacterial agent, clinicians may find it useful to determine the local and systemic concentrations of antibiotics in infected periodontal sites to reduce the levels of bacteria. The purpose of this study was to determine the serum and gingival crevicular fluid, or GCF, concentrations of systemic ciprofloxacin in patients with periodontitis.

METHODS

Ten subjects with chronic periodontitis received ciprofloxacin (500 milligrams) twice daily for five days. The authors collected GCF and serum samples immediately after administering the first dose (baseline = 0 hours) and at consecutive time points. The orifice method was used for GCF sampling, and 5 milliliters of venous blood was drawn for serum analysis. The authors used high-performance liquid chromatography to determine ciprofloxacin concentrations in GCF and serum.

RESULTS

The authors found that ciprofloxacin concentrations in GCF were significantly higher than concentrations in serum at two, four, seven, 24 and 120 hours. Ciprofloxacin reached the maximum concentration, or Cmax (3.72 micrograms/ mL), in GCF two hours after the initial dose was administered. The concentration decreased to 2.06 microg/mL 24 hours after the initial administration of the drug. Serum Cmax was 2.58 microg/mL at 1.5 hours, and the concentration decreased to 0.26 microg/mL at 24 hours.

CONCLUSION

The results of this clinical study show that ciprofloxacin is found in GCF and its concentration in GCF is significantly higher than that in serum.

CLINICAL IMPLICATIONS

Ciprofloxacin may be useful in treating patients with periodontitis because it reaches higher concentrations in GCF than in serum.

Clinical and microbiological effects of topical subgingival application of hyaluronic acid gel adjunctive to scaling and root planing in the treatment of chronic periodontitis

BACKGROUND

Hyaluronic acid (HA) has shown anti-inflammatory effects in gingivitis therapy. The potential benefits of local subgingival application of HA adjunctive to scaling and root planing (SRP) were evaluated in this study.

METHODS

Twenty patients with chronic periodontitis were included in this split-mouth study. Sulcus fluid flow rate (SFFR) and sulcus bleeding index were monitored at baseline and after 1, 2, 3, 4, 5, 6, and 12 weeks; probing depth and clinical attachment level were monitored at baseline and 6 and 12 weeks. Subgingival plaque samples were also taken at these same three appointments to determine the presence of Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia, Tannerella forsythensis, and Treponema denticola. All patients were treated with full-mouth scaling and root planing (SRP); in addition, an HA gel was administered subgingivally in the test sites every week for 6 weeks.

RESULTS

An improvement of all clinical variables was observed (P < 0.05) in both groups. Clinically, no difference between test and control sites could be found. No difference between test and control sites was seen in the tested microorganisms.

CONCLUSIONS

No clinical or microbiological improvement was achieved by the adjunctive use of HA gel compared to SRP alone. Only SFFR was affected by the use of HA in terms of a more rapid reduction of SFFR in the test sites.

Efficacy of Antibiotics Against Periodontopathogenic Bacteria Within Epithelial Cells: An In Vitro Study

BACKGROUND

Periodontopathogenic bacteria can invade and survive within epithelial cells, but susceptibility of intracellular infection to antibiotics used in periodontitis treatment has not been studied to date.

METHODS

KB cells were infected by Actinobacillus actinomycetemcomitans, strain NCTC 9710; Porphyromonas gingivalis, strains ATCC 33277 and JH16-1; or Streptococcus constellatus, strain J012b. After 2, 4, and 12 hours the bactericidal effect of antibiotics (clindamycin, doxycycline, metronidazole, and moxifloxacin) on intracellular microorganisms was tested at a concentration up to the 100-fold minimum inhibitory concentration (MIC) determined separately on planktonic bacteria.

RESULTS

The P. gingivalis strains differed in their invasiveness and ATCC 33277 was 100-fold more invasive than JH16-1. Doxycycline and clindamycin at a concentration 10-fold MIC had no effect, but P. gingivalis intercellular infection was significantly reduced by metronidazole at 10-fold MIC after 2 and 4 hours. Moxifloxacin was effective, but a 100-fold MIC concentration was necessary to reduce P. gingivalis strains intracellular growth to 7% of the control. Other bacterial species grown inside the KB cells were more susceptible to antibiotics. Clindamycin at 10-fold MIC reduced the number of intracellular S. constellatus after 4 and 12 hours. This bacterium was eliminated by moxifloxacin at 50-fold MIC. Intracellular A. actinomycetemcomitans was killed by 10-fold MIC of doxycycline and moxifloxacin after 4 hours incubation.

CONCLUSIONS

Moxifloxacin was the most efficient antibiotic to treat intracellular infection. However, taking into account the MIC values and the levels of antibiotics in gingival fluid, elimination of intracellular bacteria by antibiotics alone seems to be questionable.

Efficacy of antibiotics to strains of periodontopathogenic bacteria within a single species biofilm - an in vitro study

OBJECTIVES

This study examined differences in the efficacy of antibiotics against a single strain of three periodontal pathogens grown in an artificial biofilm.

METHODS

Single species biofilms were established with artificial saliva and one of the following bacterial strains: Actinobacillus actinomycetemcomitans Y4, Streptococcus constellatus 384b (a clinical isolate) and Porphyromonas gingivalis ATCC 33277. The efficacy of the antibiotics clindamycin, doxycycline, metronidazole, and moxifloxacin to these bacteria was determined using concentrations up to 100-fold minimal inhibitory concentration (MIC) to planctonic bacteria over 48 h.

RESULTS

The ability of the bacteria to form a biofilm varied. The biofilms of S. constellatus 384b and A. actinomycetemcomitans Y4 contained more viable bacteria and showed a larger thickness in SEM photographs than those of P. gingivalis ATCC 33277. The antibiotics tested showed different efficacy for the different strains. Moxifloxacin was the most efficient antibiotic: onefold MIC was sufficient to eliminate A. actinomycetemcomitans Y4 and P. gingivalis ATCC 33277 after 48 h. However, only the 50-fold MIC completely eradicated S. constellatus 384b. SEM photographs underlined the damaging effect of moxifloxacin on the biofilm structure.

CONCLUSION

The complete removal of bacteria by the use of antibiotics alone seems to be impossible when taking into account MIC values and the level of antibiotics in gingival fluid.

Novel mucoadhesive buccal formulation containing metronidazole for the treatment of periodontal disease

Mucoadhesive tablets using different mixture of cellulose and polyacrylic derivatives were prepared in order to obtain new formulations containing metronidazole for periodontal disease treatment. All tablets were characterized by swelling studies, ex vivo and in vivo mucoadhesive time, ex vivo mucoadhesion force, in vitro and in vivo release. The best mucoadhesive performance and the best in vitro drug release profile were achieved by using hydroxyethyl cellulose (HEC) and carbomer 940 2:2 ratio. The chosen tablet, containing 20 mg of metronidazole, performed 12 h drug sustained release with buccal concentrations always higher than its MIC.

Antimicrobials for the treatment of aggressive periodontitis

Aggressive periodontitis is characterized by a considerable attachment loss over a relatively short period of time. It may be the consequence of either the presence of highly aggressive pathogens or a highly susceptible host. In the first case, the use of antimicrobials should be beneficial in the treatment of those patients. However, due to the organization of the micro-organisms as a biofilm, the increasing incidence of allergies and resistance against antimicrobials and their side-effects, there is still controversy about their benefit in the treatment of periodontal disease. This paper discusses indications for the use of antimicrobials, the substances prescribed and the type of application under the conditions of aggressive periodontitis.

The assessment of systematic reviews in dentistry

The aim of this study was to assess the quality of systematic reviews of effectiveness of interventions in dentistry. The Database of Abstracts of Reviews of Effectiveness and the Cochrane Database of Systematic Reviews were searched to identify systematic reviews examining the effectiveness of interventions for oral, dental and craniofacial disorders and diseases. Sixty-five reviews were identified and assessed independently by two reviewers. The area most frequently evaluated within the reviews was pain relief/prevention (20/65, 31%) followed by caries and oral medicine. The quality assessment of the identified systematic reviews highlighted key areas where improvements could be made. One major weakness of the reviews was that the search strategies employed were not always adequate. Only 12 reviews (19%) demonstrated an attempt to identify all relevant studies. Other areas of weakness include the screening and quality assessment of primary studies, the pooling of data and examination of heterogeneity, and the interpretation of findings. This investigation shows that the quality of systematic reviews in dentistry could be improved. If future clinical decisions are to be based upon systematic reviews, it is imperative that the reviews address clinically relevant, focused questions and follow a 'transparent', well-designed protocol.

Clinical significance of non-surgical periodontal therapy: an evidence-based perspective of scaling and root planing

Analysis of Egyptian hieroglyphics and medical papyri indicate that non-surgical periodontal treatment was common 3000-4000 years ago. Even today, scaling and root planing (SRP) remains an essential part of successful periodontal therapy. The collective evidence from numerous clinical trials reveals a consistency of clinical response in the treatment of chronic periodontitis by SRP using manual, sonic, or ultrasonic instrumentation. Thus, SRP remains the 'gold standard' to which more recently developed therapeutic modalities must be compared. Inherent to the clinical evaluation of SRP are such concerns as manual versus sonic and ultrasonic instrumentation, control of sub-gingival bacterial populations, removal of calculus, root smoothness and changes in various clinical parameters, e.g. probing depth, attachment levels, bleeding on probing and gingival inflammation. Lastly, an abbreviated discussion is presented on a relatively new paradigm of complete mouth 'disinfection' in a compressed time-frame that includes SRP as a significant component of the treatment regimen.

Susceptibility of Porphyromonas gingivalis in biofilms to amoxicillin, doxycycline and metronidazole

The susceptibility of Porphyromonas gingivalis to amoxicillin, doxycycline and metronidazole was determined by a standardized method taking into account the biofilm mode of growth of subgingival bacteria. The minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) of 48-h biofilms of P. gingivalis established on membrane filters in a Modified Robbins Device were determined by agar dilution. The results were compared to (i) conventional MIC determinations, (ii) the susceptibility of planktonic cultures with cell numbers equal to those of the biofilms, and (iii) results for detached biofilm cells. The MICs of the biofilms of the six reference strains and clinical isolates containing 107-8 cells/filter were much higher than the conventional MIC values. However, the MIC of planktonic cultures of equal cell numbers also increased, indicating that an inoculum effect is part of the explanation of the increased resistance of biofilms. Still, the MBCs of biofilms were 2-8 times, and those for doxycycline up to 64 times, greater than the MBC values for planktonic cultures.