A multi-centre randomized controlled trial on alveolar ridge preservation with immediate or delayed implant placement: Need for soft-tissue augmentation.

AIM: To assess the impact of the timing of implant placement following alveolar ridge preservation (ARP) on the need for soft-tissue augmentation (STA) and to identify the risk factors for horizontal and vertical soft-tissue loss. MATERIALS AND METHODS: Patients with a single failing tooth in the anterior maxilla (15-25) were treated at six centres. Following tooth extraction, they were randomly allocated to the test group (immediate implant placement, IIP) or control group (delayed implant placement, DIP). ARP was performed in both groups and implants were immediately restored with an implant-supported provisional crown. Six months after tooth extraction and ARP, a panel of five blinded clinicians assessed the need for STA on the basis of anonymized clinical pictures and a digital surface model. Lack of buccal soft-tissue convexity and/or mid-facial recession qualified for STA. Pre-operative and 6-month digital surface models were superimposed to assess horizontal and vertical soft-tissue changes. RESULTS: Thirty patients were included per group (test: 20 females, 10 males, mean age 53.1; control: 15 females, 15 males, mean age 59.8). The panel deemed STA as necessary in 24.1% and 35.7% of the cases following IIP and DIP, respectively. The difference was not statistically significant (odds ratio [OR] = 1.77; 95% confidence interval [CI] [0.54-5.84]; p = .343). Loss of buccal soft-tissue profile was higher following DIP (estimated mean ratio = 1.66; 95% CI [1.10-2.52]; p = .018), as was mid-facial recession (mean difference [MD] = 0.47 mm; 95% CI [0.12-0.83]; p = .011). Besides DIP, regression analysis identified soft-tissue thickness (-0.57; 95% CI [-1.14 to -0.01]; p = .045) and buccal bone dehiscence (0.17; 95% CI [0.01-0.34]; p = .045) as additional risk factors for mid-facial recession. Surgeons found IIP significantly more difficult than DIP (visual analogue scale MD = -34.57; 95% CI [-48.79 to -20.36]; p < .001). CONCLUSIONS: This multi-centre randomized controlled trial failed to demonstrate a significant difference in the need for STA between IIP and DIP when judged by a panel of blinded clinicians. Based on objective soft-tissue changes, patients with thin buccal soft tissues, with a buccal bone dehiscence and treated with a delayed approach appeared particularly prone to soft-tissue loss.

Effects of Omega-3 as an adjuvant in the treatment of periodontal disease: A systematic review and meta-analysis.

BACKGROUND AND OBJECTIVES: Promoting resolution of inflammation using new classes of lipids mediators has been proposed for the management of inflammatory disease. This systematic review and meta-analysis aimed to evaluate the benefits of the use of omega-3 fatty acids as an adjuvant in the nonsurgical treatment of periodontitis. MATERIAL AND METHODS: The data search was conducted into three main databases: PubMed, Embase, and Cochrane. The search equation was built around the PICO framework in which the population was constituted by human adults suffering from chronic periodontitis that had to be treated with conventional SRP with the adjunction of omega-3 fatty acids (I) or without the adjunction of omega-3 fatty acids (C), with, as a first outcome the probing pocket depth reduction (PPD) and as a second outcome the clinical attachment loss reduction (CAL). Risk of bias within studies was evaluated for each included study using the Cochrane collaboration tool for randomized studies (RoB Tool). A meta-analysis was performed using REVMAN 5.3. RESULTS: After a global search, 117 studies were selected but only seven of them were eligible for the systematic review and meta-analysis. Six out of seven studies showed a significantly better PPD reduction in the omega-3 fatty acids group compared to the control group and five out of seven studies showed a significantly better CAL reduction in the omega-3 fatty acids group compared to the control group. The meta-analysis showed a statistically significant difference for PPD reduction (SMD: -0.78 [95% CI: -1.02, -0.54, p < .0001]) and CAL reduction (SMD: -0.80 [95% CI: -1.04, -0.56, p < .0001]) in favor of the test group. CONCLUSION: After scaling and root planning, PPD reduction and CAL reduction were observed in both control and test groups, but with statistically significant better values for the omega-3 fatty acids group. Patients suffering from periodontitis could benefit from the use of omega-3 fatty acids to increase the effectiveness of a nonsurgical treatment.

Glycemic and Insulin Status in Periodontitis Patients using the Homeostasis Model Assessment (HOMA): A Pilot Study.

PURPOSE: This study aimed to compare insulin status and dysglycemia (prediabetes/diabetes) of patients with chronic (stage III, grade B) or aggressive periodontitis (stage III, grade C) to that of a healthy population. MATERIALS AND METHODS: Patients with chronic (CP, n = 16) or aggressive periodontitis (AP, n = 15) and periodontally healthy controls (n = 32) were recruited. Body mass index was calculated. Glycemia, plasma insulin, glycated hemoglobin, C-reactive protein, and lipid levels were measured in fasting. The Homeostasis Model Assessment was used to calculate the insulin sensitivity (HOMA-%S), the beta-cell function (HOMA-%B), and their hyperbolic product (HOMA-%BxS). RESULTS: The CP group showed statistically significantly insulin resistance with a lower HOMA-%S (p = 0.0003) and a reduced HOMA-%BxS (p = 0.049) despite a higher insulin level (p = 0.01) vs the control group, even after BMI adjustment. There was also a trend to dysglycemia (prediabetes/diabetes) in the chronic group. In patients with AP, no abnormalities in insulin status were observed and glycemic levels were comparable with controls. Additionally, patients in both AP and CP groups presented significantly higher CRP levels compared to those of the control group (p = 0.02). CONCLUSION: Patients with CP showed reduced insulin sensitivity, increased insulin levels but a reduced %BxS product and a trend to dysglycemia. These abnormalities were not observed in AP.

Should systemic antibiotics be prescribed in periodontal abscesses and pericoronitis? A systematic review of the literature.

This study assessed whether systemic antibiotics are beneficial or harmful in patients who present with an acute periodontal abscess or pericoronitis, with or without systemic involvement, and, if antibiotics are beneficial, which type, dosage, and duration are the most effective. Medline, Embase, and the Cochrane Library were screened from 1948 up to 1 April 2022 for systematic reviews, randomised clinical trials (RCTs), and other studies. Dedicated websites were consulted for systematic reviews, clinical practice guidelines, and health technology assessments on the topic. Outcomes of interest comprised tooth survival, swelling, pain, tooth mobility, periodontal probing depth, suppuration, adverse effects, quality of life measurements, and medication required for pain relief. Overall, five guidelines, seven systematic reviews, 15 RCTs, and 34 other studies were identified and selected for full-text assessment, but none of them fulfilled the inclusion criteria. At present there is no single randomised or non-randomised controlled trial assessing the harms and clinical effectiveness of systemic antibiotics in adults with a periodontal abscess or pericoronitis.

Combination of a Hydraulic Device and Nanohydroxylapatite Paste for Minimally Invasive Transcrestal Sinus Floor Elevation: Procedure and 4-Year Results.

PURPOSE: The objectives of this retrospective study were to describe a transcrestal sinus floor elevation technique combining the use of a hydraulic device and a nanohydroxylapatite paste and to report on 4-year clinical and radiographic outcomes. MATERIALS AND METHODS: The sinus floor elevation procedure used a specially designed drill (SinusJet) to start sinus membrane unsticking and a nanohydroxylapatite paste (Ostim) for further sinus membrane elevation and bone augmentation. It was performed as a one-step procedure with immediate implant placement or a two-step procedure with delayed implant placement 9 months later. Implant survival rate, sinus membrane perforation, postoperative complications, and the level of intraoperative and postoperative patient comfort using a visual analog scale were analyzed retrospectively. A nonparametric Wilcoxon matched-pairs test and parametric paired t test were used to identify significant differences. RESULTS: One hundred thirty-six sinus floor elevations were performed in 110 patients at two dental clinics in Belgium with a mean follow-up period of 48 months. In the one-step procedure, the mean 6-month elevation was 8.5 ± 2.7 mm; 194 implants were placed. In the two-step procedure, the mean 9-month elevation was 9.5 ± 2.4 mm; 8 implants were placed. The osteotomy, sinus membrane elevation, and bone grafting typically took less than 3 minutes. Sinus membrane perforation was observed in 2.9% (n = 4/136). The 4-year implant survival rate was 97% (n = 196/202), with six early implant losses. 96.4% of patients reported either no or minimal discomfort. CONCLUSION: This minimally invasive transcrestal sinus floor elevation procedure that combines a hydraulic device and nanohydroxylapatite paste appears to be safe and predictable. However, further randomized controlled studies are needed to validate the results of this retrospective observational study.

Evaluation of multiple subgingival irrigations with 10% povidone-iodine after scaling and root planing: a randomized clinical trial.

OBJECTIVES: This 6-month randomized controlled study aimed at evaluating the clinical outcomes of multiple irrigations of 10% povidone-iodine (PVP-I) as an adjunct to full-mouth scaling and root planing (SRP) in the treatment of chronic periodontitis. METHOD AND MATERIALS: Seventeen patients were included. A split-mouth design randomly assigned one side as the test side (SRP + PVP-I) and the other side as the control side (SRP + NaCl). After full-mouth SRP, the control side received subgingival irrigation with 10 mL 0.9% NaCl solution. The test side received 10 mL of PVP-I 10%. Plaque Index (PI), bleeding on probing (BOP), probing pocket depth (PPD), and clinical attachment level (CAL) parameters were assessed at baseline and after 3 and 6 months. During recall visits (3 and 6 months), residual deep periodontal pockets of ≥ 6 mm were cleaned with the same protocol and randomization. RESULTS: PI, BOP, PPD, and CAL were improved in both sides after 6 months. No significant differences were seen between control and test sides for the all clinical parameters after 6 months. CONCLUSION: Multiple subgingival irrigations of 10% PVP-I or 0/9% NaCl combined to one-stage full mouth SRP in patients with chronic periodontitis showed a reduction of all clinical parameters until 6 months. There was a trend in favor of the povidone group for PPD. ( 2021;52:496-504; doi: 10.3290/j.qi.b1044059).

Clinical and Microbiological Profiles of Aggressive and Chronic Periodontitis in Congolese Patients: A Cross-sectional Study.

BACKGROUND: Chronic and aggressive periodontitis were the main forms of periodontitis according to the 1999 classification of periodontal diseases and conditions. Their profile in Congolese patients is still undescribed. AIM: The aim of this study was to compare the profile of chronic periodontitis (ChP) with that of aggressive periodontitis (AgP) in Congolese patients. MATERIALS AND METHODS: Thirty-two patients with ChP and 20 with AgP who consulted the dental services at any of the four medical centers in Kinshasa, from April 2017 to April 2018, were enrolled in the cross-sectional study. All patients underwent a full mouth examination, including assessment of the probing pocket depth and clinical attachment level at six sites per tooth. Microbial samples were collected in the deepest pocket in the maxilla and the deepest pocket in the mandible. A deoxyribonucleic acid (DNA) analysis was performed using DNA strip technology. Fisher exact test, the chi-square test, the t test, and the Mann-Whitney test were used for the statistical analysis. RESULTS: Patients with AgP were significantly younger than those with ChP (P < 0.001). There was no significant difference in the prevalence of Porphyromonas gingivalis, Tannerella forsythia, Treponema denticola, or Prevotella intermedia between the AgP and ChP groups (P > 0.05). Aggregatibacter actinomycetemcomitans was detected in 10% of cases in the AgP group and in none of those in the ChP group (P = 0.143). CONCLUSION: This study shows that the clinical profiles of ChP and AgP are similar in Congolese patients. There were no microbiological differences between these two forms of periodontitis.

The Effects of 6-Month Vitamin D Supplementation during the Non-Surgical Treatment of Periodontitis in Vitamin-D-Deficient Patients: A Randomized Double-Blind Placebo-Controlled Study.

BACKGROUND: This study assessed the effects of weekly vitamin D (VD) supplementation on clinical and biological parameters after scaling and root planning (SRP) in the treatment of periodontitis and served to validate the VD dosage regimen. METHODS: It was a monocentric, randomized, double-blind, placebo-controlled clinical trial with 6 months follow-up. Healthy Caucasian periodontitis patients presenting serum 25(OH) vitamin D3 below 30 ng/mL were randomly allocated to test group (SRP + VD 25,000 international units (IU)/week) or the control group (SRP + placebo). RESULTS: A total of 59 patients were screened, 27 were included and 26 completed 3 months (M) and 21 completed 6M control. Test (n = 13) and control groups (n = 14) had similar 25(OH) vitamin D3 levels at baseline (17.6 ± 7.4 vs. 14.4 ± 5.2, respectively). After one month, there was a significant difference between groups (32.9 ± 5.2 vs. 16.1 ± 4.7), also seen at M3 and M6 (t-test, p < 0.001). Periodontal treatment was successful in both groups, since it resulted in a reduction of all measured clinical parameters at M3 and M6 (probing pocket depth (PPD), full mouth bleeding and plaque). However, the reduction in PPD was greater in the test group. CONCLUSIONS: In this short-term pilot study, no significant differences were observed between two groups. However, supplementation with VD tended to improve the treatment of periodontitis in patients with initial 25(OH) vitamin D3 < 30 ng/mL and proved safe and efficacious. NCT03162406.

Implantoplasty Versus Glycine Air Abrasion for the Surgical Treatment of Peri-implantitis: A Randomized Clinical Trial.

PURPOSE: Numerous approaches have been proposed for the treatment of peri-implantitis, but to date, none has been identified as the most effective. This study compared the efficacy of implantoplasty and glycine air polishing for the surgical treatment of peri-implantitis. MATERIALS AND METHODS: This prospective, randomized, parallel-group trial included 31 patients presenting with 42 implants with peri-implantitis. Patients underwent surgical treatment by implantoplasty (test group, n = 22) or glycine air polishing (control group, n = 20). Clinical parameters (Plaque Index), bleeding on probing (BOP), suppuration on probing (SOP), probing pocket depth (PPD), relative attachment level (RAL), and mucosal recession were assessed before surgery (baseline), and at 3 months and 6 months after surgery. Bone loss was recorded at baseline and 6 months. Two composite outcomes were also evaluated, according to the following definitions: (1) mean PPD reduction ≥ 0.5 mm + no further loss of bone; (2) PPD ≤ 5 mm, absence of BOP/SOP, and no additional mean bone loss ≥ 0.5 mm. RESULTS: Plaque Index remained low (< 0.5) in both groups for the duration of the study. Mean BOP, SOP, PPD, and RAL were greatly reduced at 3 months in both groups, and remained low between 3 months and 6 months. Bone loss was stable in the implantoplasty group, and slight bone gain (0.5 mm) was observed in the glycine air-polishing group. There were no significant differences between the two groups in any parameter, and composite treatment outcomes were similar in both groups, irrespective of the definition. CONCLUSION: Within the limitations of this 6-month follow-up study, implantoplasty is as effective as glycine air polishing for the surgical treatment of peri-implantitis.

Treatment of mandibular Class II furcations using bovine-derived bone xenograft with or without a collagen membrane: a randomized controlled trial.

OBJECTIVES: This randomized clinical trial aimed to compare the effects of a bovine-derived xenograft with (control group, CG) or without (test group, TG) a collagen membrane for the treatment of mandibular Class II furcations. METHOD AND MATERIALS: Nineteen patients presenting 32 furcations were included and randomly assigned to CG (n = 16) or TG (n = 16). At the 6-month follow-up (M6), 29 furcations were reevaluated. All clinical measurements were performed by the same investigator with a straight periodontal probe and a specially designed "modified Nabers probe" (both with 1-mm increments). The primary outcome was the improvement of the horizontal probing attachment level. According to the protocol, there was no re-entry at 6 months. RESULTS: Both vertical (at M6, CG: 2.4 ± 0.8 mm, TG: 2.7 ± 1.0 mm) and horizontal probing attachment levels, whether measured with a periodontal probe (at M6: CG: 3.4 ± 0.8 mm, TG: 3.2 ± 1.0 mm) or the "modified Nabers probe" (at M6: CG: 3.5 ± 1.1 mm, TG: 3.2 ± 1.0 mm), favorably evolved after 6 months. There was no significant difference for any of the measures performed (P > .05, unpaired t test). CONCLUSIONS: Both treatments were clinically effective with no statistically significant difference between them but as there was no histologic analysis, the amount of real regeneration could not be analyzed. This conclusion should be confirmed by longer follow-up periods.

Clinical Evaluation of Three Surgical Modalities in the Treatment of Peri-Implantitis: A Randomized Controlled Clinical Trial.

OBJECTIVES: To compare the efficacy of three mechanical procedures for surgically treating peri-implantitis. MATERIALS AND METHODS: In a randomized, prospective, parallel-group study, 47 patients with peri-implantitis were treated with (a) plastic curettes (n = 15 patients, 25 implants), (b) an air-abrasive device (Perio-Flow®, n = 16 patients,22 implants), or (c) a titanium brush (Ti-Brush®, n = 16 patients, 23 implants). Patients were assessed for the following measures at three timepoints (baseline, and three and six months after surgery): plaque index, bleeding on probing, gingival index, probing pocket depth (PPD), relative attachment level, and bone loss. Treatment outcome was considered successful when the implant was still present with PPD ≤ 5 mm, no bleeding on probing, and no further mean bone loss ≥ 0.5 mm. RESULTS: A greater reduction of gingival index and PPD was observed in the titanium brush group than in the other groups at six months (P < 0.001). Relative attachment level decreased from baseline in each group at three months but was more marked in the titanium brush group (P < 0.001). At six months, there was less bone loss in the titanium brush group than in the plastic curette group (P < 0.001; linear mixed model and Kruskal-Wallis). A successful outcome was observed in 22% of implants in the plastic curette group, 27% in the Perio-Flow® group, and 33% in the Ti-Brush® group. CONCLUSIONS: The titanium brush and glycine air-polishing device were more effective than the other methods, but treatment success remained low. Combining mechanical procedures with antimicrobials and/or antibiotics might be a more effective strategy and warrants careful investigation.

In Vitro Comparison of the Efficacy of Peri-Implantitis Treatments on the Removal and Recolonization of Streptococcus gordonii Biofilm on Titanium Disks.

Objective: To compare the efficacy of four commonly used clinical procedures in removing Streptococcus gordonii biofilms from titanium disks, and the recolonization of the treated surfaces. Background: Successful peri-implantitis treatment depends on the removal of the dental biofilm. Biofilm that forms after implant debridement may threaten the success of the treatment and the long-term stability of the implants. Methods: S. gordonii biofilms were grown on titanium disks for 48 h and removed using a plastic curette, air-abrasive device (Perio-Flow®), titanium brush (TiBrush®), or implantoplasty. The remaining biofilm and the recolonization of the treated disks were observed using scanning electron microscopy and quantified after staining with crystal violet. Surface roughness (Ra and Rz) was measured using a profilometer. Results: S. gordonii biofilm biomass was reduced after treatment with Perio-Flow®, TiBrush®, and implantoplasty (all p < 0.05), but not plastic curette (p > 0.05), compared to the control group. Recolonization of S. gordonii after treatment was lowest after Perio-Flow®, TiBrush®, and implantoplasty (all p < 0.05 vs. control), but there was no difference between the plastic curette and the control group (p > 0.05). Ra and Rz values ranged from 1⁻6 µm to 1⁻2 µm and did not differ statistically between the control, plastic curette, Perio-Flow, and TiBrush groups. However, the implantoplasty group showed a Ra value below 1 µm (p < 0.01, ANOVA, Tukey). Conclusions: Perio-Flow®, TiBrush®, and implantoplasty were more effective than the plastic curette at removing the S. gordonii biofilm and preventing recolonization. These results should influence the surgical management of peri-implantitis.

Oral Microbes, Biofilms and Their Role in Periodontal and Peri-Implant Diseases.

Despite many discoveries over the past 20 years regarding the etio-pathogenesis of periodontal and peri-implant diseases, as well as significant advances in our understanding of microbial biofilms, the incidence of these pathologies still continues to rise. This review presents a general overview of the main protagonists and phenomena involved in oral health and disease. A special emphasis on the role of certain keystone pathogens in periodontitis and peri-implantitis is underlined. Their capacity to bring a dysregulation of the homeostasis with their host and the microbial biofilm lifestyle are also discussed. Finally, the current treatment principles of periodontitis and peri-implantitis are presented and their limits exposed. This leads to realize that new strategies must be developed and studied to overcome the shortcomings of existing approaches.

Cowden Syndrome Associated with Severe Periodontal Disease: A Short Literature Review and a Case Report.

PURPOSE: The aim of this literature review and case report was to point out the relationship between Cowden Syndrome (CS) and severe periodontitis. CS is a rare autosomal dominant disorder characterised by skin and oral hamartomas, and is associated with an increased risk of cancer development. CASE REPORT: The case of a 43-year old male patient affected by Cowden syndrome and presenting severe periodontitis was reported. RESULTS: It can be suggested that the specific gingival morphology of the patient with CS might be a risk factor for the development of periodontal disease, as described in the present case report. CONCLUSION: Early diagnosis is crucial in patients affected by CS. The dentist may be the first to notice any atypical changes in the oral cavity and refer the patient for further examinations. Moreover, the mucosal and skin changes have a tendency to appear prior to the malignancies associated with the syndrome. This highlights the responsibility of the dentist in the early diagnosis of this progressive pathological syndrome.

Evaluation of Emdogain® antimicrobial effectiveness against biofilms containing the keystone pathogen Porphyromonas gingivalis.

This study aimed to evaluate the antimicrobial activity of Emdogain® (EMD) against biofilms containing the periopathogen Porphyromonas gingivalis. A brain-Heart infusion broth inoculated with S. gordonii and P. gingivalis was perfused (7-d, anaerobiosis) through a closed circuit containing two Robbins devices as to form biofilms. The latter were then treated for 2 min with various antimicrobials (Chlorhexidine (CHX) 0.2%, Povidone iodine (PVI) 5%, PVI 10%, essential oils (EO), EO ZeroTM or EMD) (n=8) and cell densities were calculated and compared. In the present in vitro model, Emdogain® was not statistically effective (p>0.05) in killing biofilm bacteria unlike the other tested molecules.

Evaluation of a unique subgingival irrigation with 10% povidone-iodine after scaling and root planing: A randomized clinical trial.

OBJECTIVE: The beneficial effects of antiseptics in the treatment of periodontitis are still controversial. The goal of this randomized split-mouth study was to evaluate the clinical and microbiologic results of a unique subgingival irrigation of 10% povidone-iodine in addition to a full-mouth scaling and root planing for the treatment of chronic periodontitis. METHOD AND MATERIALS: Twenty patients with chronic periodontitis took part in this investigation. In each patient, four initially untreated pockets ≥ 4 mm were randomly selected for one subgingival irrigation. After a one-session full-mouth treatment with scaling and root planing (SRP), two pockets of a split mouth received one unique irrigation with 10 mL 0.9% NaCl solution (control group, CG). Two pockets on the other side received 10 mL of povidone-iodine 10% (test group, PIG). Full-mouth plaque score (FMPS), full-mouth bleeding score (FMBS), Plaque Index (PI), Gingival Index (GI), probing pocket depth (PPD), and clinical attachment level (CAL) parameters were assessed at baseline and after 1, 3, and 6 months (M). Bacterial samplings with sterile paper points were taken at M0 and after M1, M3, and M6. These samplings were separately cultured under aerobic and anaerobic conditions before CFU evaluation. RESULTS: Pl, GI, PPD, and CAL were significantly improved in both groups after 6 months. The major difference was seen between M0 and M3 (P < .001). No significant differences were seen between the groups, except for deep pockets (> 6 mm) where a statistical difference was observed in favor of PIG after 6 months; in these subgroups the mean probing reduction was 2.68 ± 0.37 mm for CG versus 3.93 ± 0.23 mm in PIG (P < .001). No significant differences were seen between CG and PIG regarding the microbiologic results after 6 months. CONCLUSION: One single irrigation of 10% povidone-iodine associated with full-mouth SRP would bring a small additional benefit in deep pockets. More studies are needed to yield additional results.

Influence of low direct electric currents and chlorhexidine upon human dental biofilms.

Dental biofilms have been widely associated with biological complications of oral implants. Currently, no consensus exists regarding the most reliable anti-infective approach to treat peri-implantitis. This study aimed to investigate whether low direct electric currents (DC) could influence chlorhexidine (CHX) 0.2% antimicrobial efficacy against human dental biofilms. To support biofilm accumulation, discs made with machined titanium (Ti) or hydroxyapatite (HA) were used. Five volunteers wore during 24 h an intraoral thermoformed splint on which ten specimens were bonded. Biofilms were then collected and treated ex vivo. During each antimicrobial experiment (N = 20 replicates), two modalities of treatment (CHX/PBS = control groups and CHX/PBS+5mA = test groups) were tested (n = 5 discs each) and the number of viable bacteria evaluated in LogCFU/mL at baseline, 0.5, 1, 2 and 5 min. The proportion of killed bacteria was also estimated and compared statistically at each time point between control and test groups. CHX+/-5mA induced a mean viability reduction around 90-95% after 5 min of treatment whatever the surface considered (Ti/HA). A significant difference regarding the bactericidal effect was noted on Ti surfaces after 0.5, 1 and 2 min in favor of the CHX+5mA modality when compared to CHX alone (p < 0.05). PBS+5mA also had a certain antimicrobial effect (58%) after 5 min on Ti surfaces. This effect was significantly higher than that observed with PBS (25%) (p < 0.05). This study showed that low DC (5mA) can have an antibiofilm effect and are also able to enhance chlorhexidine 0.2% efficacy against human dental biofilms grown on titanium surfaces.

In vitro evaluation of peri-implantitis treatment modalities on Saos-2osteoblasts.

OBJECTIVES: Mechanical treatment of the implant surface through surgical approach is recommended to control peri-implantitis. Few conclusive data exist about the physical and chemical properties of treated titanium surfaces and their biocompatibility towards osteoblasts. This in vitro study aimed to evaluate four clinical procedures: plastic curette, air-abrasive device (Perio-Flow(®) ), titanium brush (Ti-Brush(®) ) and implantoplasty in terms of biocompatibility and osteogenic effect when cultured with Saos2. MATERIALS AND METHODS: Titanium disks were treated with plastic curette, air-abrasive device (Perio-Flow(®) ), titanium brush (Ti-Brush(®) ) and implantoplasty. Their surface microtopography (SEM), chemical composition (EDX) and wettability were evaluated. After seeding with Saos-2, cell morphology (1 h, 24 h), viability (three and 6 days) and alkaline phosphatase (ALP), osteoprotegerin (OPG) and osteocalcin (OCN) production (7 days) were analyzed. RESULTS: Control, plastic curette, Perio-Flow(®) and Ti-Brush(®) groups presented complex microstructures including craters and micropits, whereas the implantoplasty group appeared much smoother (SEM). Titanium, oxygen, aluminium and carbon were identified as the main components in all disks with a decrease in the percentage of oxygen, carbon and an increase in the percentage of titanium in the implantoplasty group (EDX). Implantoplasty disks were also significantly more hydrophilic than the other ones, whose surfaces appeared hydrophobic. Saos-2 showed no morphological difference at 1 h. At 24 h, they appeared round shaped in all groups, except the implantoplasty group where the cells appeared stretched and elongated. Viability was similar in all groups, but significantly higher in the Perio-Flow(®) than the control group at day six. ALP, OPG and OCN protein expression at 7 days was similar in all groups. CONCLUSIONS: Although implantoplasty was the only modality to modify the titanium surface morphology, composition and wettability, all treatment modalities promoted ALP, OPG and OCN production and appeared as valid approaches in terms of biocompatibility.

Electrical enhancement of chlorhexidine efficacy against the periodontal pathogen Porphyromonas gingivalis within a biofilm.

Electric currents have been shown to promote the antimicrobial effectiveness of several biocides against microbial biofilms. Therefore, the objective of this work was to test the null hypothesis that low electric direct currents (DC) do not influence chlorhexidine (CHX) efficacy against the periodontal pathogen Porphyromonas gingivalis within a biofilm. A brain heart infusion medium inoculated with Streptococcus gordonii and P. gingivalis was perfused for 7 days in anaerobiosis through two modified Robbins devices (MRD) assembled in parallel. Biofilms grew on hydroxyapatite discs placed at the bottom of the MRD plugs, and were then treated for 10 min with either CHX or CHX/DC (1.5 mA or 10 mA). The bactericidal effect against biofilms was then evaluated by comparing the mean proportions of P. gingivalis killed. In the first series of experiments (CHX ± 1.5mA), the proportions of P. gingivalis killed were 81.1% for biofilms undergoing CHX and 79.1% when they were additionally treated with 1.5mA (p>0.05). In the second series (CHX ± 10mA), the viability of P.gingivalis was reduced by 87.3% with CHX and 98.9% when CHX was supplemented with 10mA (p<0.01). The null hypothesis was rejected, since a significant enhancement of the chlorhexidine 0.2% efficacy against P.gingivalis was observed when applying 10mA currents.

Evaluation of an air-abrasive device with amino acid glycine-powder during surgical treatment of peri-implantitis.

OBJECTIVE: The aim of this retrospective study was to analyze collected data concerning the effect of an air-abrasive device (Perio-Flow®) during surgical treatment of peri-implantitis without addition of any antimicrobials. METHOD AND MATERIALS: Data reports from 22 implants with peri-implantitis surgically treated using either an air-abrasive device (Perio- Flow) (test group), or plastic curettes and cotton pellets impregnated with saline (control group) were analyzed for the present study. Clinical and radiographic parameters plaque index (PI), gingival index (GI), probing pocket depth (PPD), and bone loss (BL) were previously assessed at baseline, 6 months, and 12 months after treatment. A repeated measures ANOVA test was used for each clinical and radiographic parameter (PI, GI, PPD, and BL). The implant and the patient were considered separately as the statistical unit. RESULTS: Regarding betweengroup comparisons, PI scores remained low during the entire study period (at implant and patient levels). At the end of the study, GI and PPD reductions were statistically higher (P < .05) in the Perio-Flow group (implant level), and no differences were observed between the two groups at patient level (P > .05) (repeated measures ANOVA test). It was also noted that BL analyses (implant and patient levels) revealed no differences between baseline and 12 months in both groups. Nevertheless, only 8% from each treatment group were considered stabilized after 12 months. CONCLUSION: Within the limitations of the present study, both groups (Perio-Flow and its control group) revealed a significant reduction of the clinical parameters. Moreover, the air-abrasive device group yielded better improvements regarding GI and PPD when the implant was considered as the statistical unit. However, if the stabilization of the disease was the final objective, these two treatments failed in resolving its activity. A longer follow-up and a larger number of patients would be needed to confirm these results and the benefit of adding this air-abrasive method of decontamination to the surgical procedure.