Clinical and microbiological effects of a single application of sodium hypochlorite gel during subgingival re-instrumentation: a triple-blind randomized placebo-controlled clinical trial.

OBJECTIVES: The aim of this study is to assess the clinical and microbiological effects of a single subgingival administration of sodium hypochlorite gel (NaOCl) and compare it with 1% chlorhexidine (CHX) gel and a placebo gel following mechanical re-instrumentation during supportive periodontal therapy (SPT). MATERIALS AND METHODS: Sixty-two patients who had been treated for stage III-IV periodontitis and enrolled in SPT were included in the study based on following criteria: (1) active periodontal therapy completed at least 6 months before enrollment in the study, (2) presence of at least 4 non-adjacent sites with probing pocket depths (PPDs) ≥ 4 mm with bleeding on probing (BOP), or presence of 5-8 mm PPDs with or without BOP. All sites presenting PPD ≥ 4 mm and BOP at baseline and 3-, 6-, and 9-month follow-up timepoints were subgingivally re-instrumented with ultrasounds. Selected patients were randomly assigned into three groups and treated additionally with a single subgingival administration of NaOCl gel (group A); 1% CHX gel (group B); and placebo gel (group C). Main outcome variable was pocket closure at 12 months. Secondary outcome variables were changes in mean PPD, BOP, and clinical attachment level (CAL) along with changes in the numbers of the following five keystone bacterial pathogens: Aggregatibacter actinomycetemcomitans (A.a.), Porphyromonas gingivalis (P.g.), Prevotella intermedia (P.i.), Tannerella forsythia (T.f.), and Treponema denticola (T.d.). RESULTS: At 12 months, pocket closure was obtained in 77.5% in the NaOCl treated sites. The reduction in PPD was higher with CHX than with NaOCl, although a statistically significant adjunctive effect for NaOCl (P = 0.028) was only observed in comparison with placebo only. Mean CAL improved in all groups and at all timepoints, compared to the baseline (P < 0.05). However, after 6 months, CAL gain was statistically significantly higher in the NaOCl treated group than following application of CHX (P = 0.0026). CONCLUSION: In SPT patients, a single adjunctive use of a NaOCl gel may provide benefits in controlling inflammation and residual pockets. TRIAL REGISTRATION: ISRCTN Registry of Clinical Trials (ISRCTN11387188). CLINICAL RELEVANCE: A baseline single application of NaOCl gel in conjunction with mechanical debridement may achieve substantial pocket closure in patients enrolled in SPT; treatment time, cost, and applicability considerations should be taken into account when selecting this therapy.

The effects of a desiccant agent in the treatment of chronic periodontitis: a randomized, controlled clinical trial.

OBJECTIVE: Chemotherapeutic agents have been widely used as adjuncts for the treatment of chronic periodontitis (CP). This study investigated and compared a desiccant agent as an adjunct to scaling and root planing (SRP) versus SRP alone for the treatment of CP. MATERIALS AND METHODS: Thirty-six patients with CP were studied. Using a split-mouth design, the maxillary right and left quadrants were randomly assigned to SRP plus desiccant (Hybenx® EPIEN Medical, Inc. St. Paul, MN, USA) or SRP alone. Patients were examined on a regular basis for clinical, microbiological, and inflammatory mediator changes over a 1-year period. Clinical attachment level (CAL) was the primary outcome variable. In addition, the red complex bacteria and gingival crevicular fluid (GCF) inflammatory mediators were monitored. RESULTS: Compared to baseline, both treatments demonstrated an improvement in periodontal parameters. Compared to SRP alone, SRP plus desiccant yielded a significant improvement in probing depth (PD) (SRP: 2.23 ± 0.31 mm vs. desiccant: 3.25 ± 0.57 mm, p < 0.05), CAL (SRP: 3.16 ± 0.29 mm vs. desiccant: 4.21 ± 0.34 mm, p < 0.05 mm) and bleeding on probing (BOP) (SRP: 4.56 ± 1.5% vs. desiccant: 34.23 ± 4.2%, p < 0.001) at 12 months. Similarly, in the SRP plus desiccant group, the bacteria of the red complex were significantly reduced (p < 0.05); and the level of inflammatory mediators was significantly reduced (p < 0.003) compared to SRP alone. CONCLUSIONS: SRP plus the desiccant resulted in a greater reduction in clinical, microbial and inflammatory mediators compared to SRP alone. CLINICAL RELEVANCE: Desiccant, when combined to SRP, was demonstrated as a significant approach to control the levels of certain periodontal pathogens, inflammatory mediators in patients with CP.

Soft and hard tissues healing at immediate transmucosal implants placed into molar extraction sites with collagen membrane uncovered: a 12-month prospective study.

PURPOSE: To assess soft and hard tissues healing at immediate transmucosal implants placed into maxillary molar region with collagen membranes uncovered. MATERIALS AND METHODS: Twenty subjects received 20 immediate transmucosal implants placed in maxillary molar extraction sockets. Periimplant marginal defects were treated according to the principles of guided bone regeneration by means of deproteinized bovine bone mineral particles in conjunction with collagen membrane. Flaps were repositioned and sutured, allowing nonsubmerged, transmucosal soft tissues healing. The collagen membranes adapted around implant neck were uncovered. RESULTS: No implants were lost during the 1-year observation period yielding a survival rate of 100%. No postsurgical wound healing complications were observed. No degranulation of grafting material was reported. CONCLUSIONS: The results of this 12-month prospective study showed that the exposure of collagen membrane at time of the flap suturing does not represent a limitation for the soft and hard tissues healing at immediate transmucosal implants placed into maxillary molar extraction sites.

A 10-year retrospective analysis of marginal bone-level changes around implants in periodontally healthy and periodontally compromised tobacco smokers.

AIM: to compare the 10-year marginal bone loss rates around implants supporting single-unit crowns in tobacco smokers with and without a history of treated periodontitis. MATERIALS AND METHODS: in this retrospective controlled study, 40 tobacco smokers were divided into four groups of 10 patients each. Two groups of periodontally compromised (PC) patients and two groups of periodontally healthy (PH) patients were established. PC patients had been treated for their periodontal conditions before implant placement. All patients were enrolled in a regular, individually tailored maintenance care program. For the rehabilitation of PC and PH patients, two different types of implants were used (Nobel Biocare AB; Straumann Dental Implant System). The radiographic bone loss rate was calculated by subtracting the bone levels at the time of crown delivery from the bone levels at the 10-year follow-up. RESULTS: the mean age, mean full-mouth plaque score and full-mouth bleeding score and implant location were similar for the four groups. Implant survival rates ranged between 70% and 100%, without statistically significant differences between the four groups (P>0.05). Implants placed in PC patients yielded statistically significantly higher marginal bone loss rates compared with those in PH patients (P<0.05), independent of the implant system used. CONCLUSION: after 10 years, implants placed in tobacco smokers with a history of treated periodontitis and enrolled in a supportive therapy program yielded lower survival rates and higher marginal bone loss rates compared with those of implants placed in PH smokers. These outcomes were independent of the implant system installed or the healing modality applied.

A systematic review of the survival and complication rates of implant supported fixed dental prostheses with cantilever extensions after an observation period of at least 5 years.

OBJECTIVE: The aim of this systematic review was to assess the survival rates of short-span implant-supported cantilever fixed dental prostheses (ICFDPs) and the incidence of technical and biological complications after an observation period of at least 5 years. MATERIAL AND METHODS: An electronic MEDLINE search supplemented by manual searching was conducted to identify prospective or retrospective cohort studies reporting data of at least 5 years on ICFDPs. Five- and 10-year estimates for failure and complication rates were calculated using standard or random-effect Poisson regression analysis. RESULTS: The five studies eligible for the meta-analysis yielded an estimated 5- and 10-year ICFDP cumulative survival rate of 94.3% [95 percent confidence interval (95% CI): 84.1-98%] and 88.9% (95% CI: 70.8-96.1%), respectively. Five-year estimates for peri-implantitis were 5.4% (95% CI: 2-14.2%) and 9.4% (95% CI: 3.3-25.4%) at implant and prosthesis levels, respectively. Veneer fracture (5-year estimate: 10.3%; 95% CI: 3.9-26.6%) and screw loosening (5-year estimate: 8.2%; 95% CI: 3.9-17%) represented the most common complications, followed by loss of retention (5-year estimate: 5.7%; 95% CI: 1.9-16.5%) and abutment/screw fracture (5-year estimate: 2.1%; 95% CI: 0.9-5.1%). Implant fracture was rare (5-year estimate: 1.3%; 95% CI: 0.2-8.3%); no framework fracture was reported. Radiographic bone level changes did not yield statistically significant differences either at the prosthesis or at the implant levels when comparing ICFDPs with short-span implant-supported end-abutment fixed dental prostheses. CONCLUSIONS: ICFDPs represent a valid treatment modality; no detrimental effects can be expected on bone levels due to the presence of a cantilever extension per se.

Crestal bone changes at teeth and implants in periodontally healthy and periodontally compromised patients. A 10-year comparative case-series study.

BACKGROUND: Limited data exist on the longitudinal crestal bone changes around teeth compared with implants in partially edentulous patients. This study sought to compare the 10-year radiographic crestal bone changes (bone level [BL]) around teeth and implants in periodontally compromised (PCPs) and periodontally healthy (PHPs) patients. METHODS: A total of 120 patients were evaluated for the radiographic crestal BL around dental implants and adjacent teeth at time of implant crown insertion and at the 10-year follow-up. Sixty patients had a previous history of periodontitis (PCPs), and the remaining 60 were PHPs. In each category (PCP and PHP), two different implant systems were used. The mean BL change at the implant and at the adjacent tooth at the interproximal area was calculated by subtracting the radiographic crestal BL at the time of crown cementation from the radiographic crestal BL at the 10-year follow-up. RESULTS: At 10 years after therapy, the survival rate ranged from 80% to 95% for subgroups for implants, whereas it was 100% for the adjacent teeth. In all eight different patient categories evaluated, teeth demonstrated a significantly more stable radiographic BL compared with adjacent dental implants (teeth BL, 0.44 ± 0.23 mm; implant BL, 2.28 ± 0.72 mm; P <0.05). Radiographic BL changes around teeth seemed not to be influenced by the presence or absence of advanced bone loss (≥3 mm) at the adjacent implants. CONCLUSIONS: Natural teeth yielded better long-term results with respect to survival rate and marginal BL changes compared with dental implants. Moreover, these findings also extend to teeth with an initial reduced periodontal attachment level, provided adequate periodontal treatment and maintenance are performed. As a consequence, the decision of tooth extraction attributable to periodontal reasons in favor of a dental implant should be carefully considered in partially edentulous patients.

Clinical outcomes after treatment of non-contained intrabony defects with enamel matrix derivative or guided tissue regeneration: a 12-month randomized controlled clinical trial.

BACKGROUND: The purpose of this study is to compare the healing of deep, non-contained intrabony defects (i.e., with a ≥80% 1-wall component and a residual 2- to 3-wall component in the most apical part) treated with either an enamel matrix derivative (EMD) or guided tissue regeneration (GTR) after 12 months. METHODS: In this randomized, controlled clinical trial, 40 subjects with 40 defects affecting single-rooted teeth were treated. The defects were treated with EMD alone or with a non-resorbable titanium-reinforced membrane. No grafting materials were used. At baseline and after 12 months, clinical parameters including probing depths (PDs) and clinical attachment levels (CAL) were recorded. The difference in CAL gain was the primary outcome. RESULTS: At baseline, the intrabony component of the defects amounted to 8.5 ± 2.2 mm at EMD-treated sites and 8.6 ± 1.7 mm at GTR-treated sites (P = 0.47). The mean CAL gain at sites treated with GTR was significantly greater (P <0.001) than that at sites treated with EMD (4.1 ± 1.4 mm versus 2.4 ± 2.2 mm, respectively). GTR therapy, compared to EMD application alone, significantly (P = 0.01) increased the probability of CAL gain ≥4 mm (79.2% versus 11.3%, respectively) and significantly (P = 0.01) decreased the probability of residual PDs ≥6 mm (3% versus 79.3%, respectively). CONCLUSION: Although the outcomes of open-flap debridement alone were not investigated, the application of EMD alone appeared to yield less PD reduction and CAL gain compared to GTR therapy in the treatment of deep, non-contained intrabony defects.