Andrea Blasi

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.

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.

Dimensional ridge alterations following immediate implant placement in molar extraction sites: a six-month prospective cohort study with surgical re-entry

AIM To assess dimensional ridge alterations following immediate implant placement in molar extraction sites. MATERIAL AND METHODS Twelve subjects received 12 immediate transmucosal implants in molar extraction sites. Peri-implant defects were treated according to the principles of Guided Bone Regeneration by means of a deproteinized bone substitute and a bioresorbable collagen membrane. Changes in vertical (IS-BD, CREST-BD) and horizontal distances (EC-I, IC-I) of alveolar bony walls to the bottom of the defects (BD) and to the implant surfaces (I) were compared between implant placement and surgical re-entry at 6 months. RESULTS The implant survival rate at 6 months was 100%. Statistically significant differences (P<0.01) were observed in the mean changes in vertical distances IS-BD and CREST-BD between baseline and re-entry. At re-entry, all peri-implant marginal defects assessed from the internal socket wall to the implant surface (IC-I) were healed. The residual combined thickness of the buccal wall with the newly formed peri-implant bone at sites with an initial thickness of 1 mm was statistically significantly smaller (P<0.05) compared with that of sites with an initial buccal thickness of 2 mm (2.50 +/- 0.76 vs. 4+/-0 mm). CONCLUSIONS The marginal defects around immediate implants placed in molar extraction sites were completely filled after 6 months of healing through de novo bone formation. Bone resorption was observed from the external aspects of the buccal and oral socket walls. Dimensional changes of the external socket walls were mostly pronounced at the buccal aspects.

Clinical and radiographic changes at implants supporting single-unit crowns (SCs) and fixed dental prostheses (FDPs) with one cantilever extension. A retrospective study

OBJECTIVES To evaluate the clinical and radiographic changes at implants in posterior maxillary and mandibular areas supporting single-unit crowns (SCs) and fixed dental prostheses (FDPs) with one mesial or distal cantilever extension after an observation period of at least 3 years. MATERIAL AND METHODS Seventeen subjects with 19 implant-supported SCs and 21 subjects with 21 implant-supported FDPs fulfilled the inclusion criteria. All FDPs were supported by two implants and had a span of 3-4 units. All reconstructions were incorporated in the posterior maxilla or mandible. The mesial and distal radiographic marginal bone loss from baseline (i.e. delivery of the reconstruction) to the follow-up examination was averaged and compared between SCs supporting one cantilever extension with that of implants supporting FDPs adjacent to or distant from the cantilever extension. Changes in mean pocket probing depth (PPD) were calculated and compared between the three groups. RESULTS The mean observation period was 78.2 ± 34.5 months for SCs supported by one implant and 67.8 ± 29.8 months for FDPs supported by two implants. No implant loss occurred, yielding a 100% survival rate. At baseline, the mean radiographic bone levels ± SD were 2.6 ± 0.3 mm for implants supporting SCs, 2.6 ± 0.3 mm for implants of FDPs adjacent to the cantilever extension, and 2.4 ± 0.5 mm for implants of FDPs distant from the cantilever extension. At follow-up, the corresponding mean bone levels ± SD were 2.7 ± 0.4, 2.7 ± 0.5, and 2.8 ± 0.5 mm, respectively. No statistically significant differences (P > 0.05) were observed comparing the mean marginal bone loss between the three groups. Moreover, mean changes in PPD between baseline and follow-up were not statistically significantly different (P > 0.05) between the three groups. CONCLUSION The presence of one mesial or distal cantilever extension in the posterior maxilla or mandible does not jeopardize the marginal bone levels of implants supporting SCs or short-span FDPs after a mean observation period of at least 5 years.

Clinical Outcomes Following Regenerative Therapy of Non-Contained Intrabony Defects Using a Deproteinized Bovine Bone Mineral Combined With Either Enamel Matrix Derivative or Collagen Membrane

BACKGROUND The purpose of this study is to compare clinical outcomes in the treatment of deep non-contained intrabony defects (i.e., with ≥70% 1-wall component and a residual 2- to 3-wall component in the most apical part) using deproteinized bovine bone mineral (DBBM) combined with either enamel matrix protein derivative (EMD) or collagen membrane (CM). METHODS Forty patients with multiple intrabony defects were enrolled. Only one non-contained defect per patient with an intrabony depth ≥3 mm located in the interproximal area of single- and multirooted teeth was randomly assigned to the treatment with either EMD + DBBM (test: n = 20) or CM + DBBM (control: n = 20). At baseline and after 12 months, clinical parameters including probing depth (PD) and clinical attachment level (CAL) were recorded. The primary outcome variable was the change in CAL between baseline and 12 months. RESULTS At baseline, the intrabony component of the defects amounted to 6.1 ± 1.9 mm for EMD + DBBM and 6.0 ± 1.9 mm for CM + DBBM sites (P = 0.81). The mean CAL gain at sites treated with EMD + DBBM was not statistically significantly different (P = 0.82) compared with CM + DBBM (3.8 ± 1.5 versus 3.7 ± 1.2 mm). No statistically significant difference (P = 0.62) was observed comparing the frequency of CAL gain ≥4 mm between EMD + DBBM (60%) and CM + DBBM (50%) or comparing the frequency of residual PD ≥6 mm between EMD + DBBM (5%) and CM + DBBM (15%) (P = 0.21). CONCLUSION Within the limitations of the present study, regenerative therapy using either EMD + DBBM or CM + DBBM yielded comparable clinical outcomes in deep non-contained intrabony defects after 12 months.

Penetration of Sodium Hypochlorite Modified with Surfactants into Root Canal Dentin

The aim of this study was to evaluate the effect of concentration, exposure time and temperature of sodium hypochlorite (NaOCl) added with surfactants on its penetration into dentinal tubules. Sixty-five extracted human permanent maxillary anterior teeth with single canals were prepared by ProTaper SX hand-operated instruments. The teeth were then sectioned perpendicular to the long axis. The crowns and apical thirds of all the teeth were removed. The remaining roots were processed into 4-mm-long blocks and stained overnight in crystal violet. One hundred and thirty stained blocks were further split into halves and treated by nine different types of NaOCl-based solutions. Three solutions were added with surfactants (Hypoclean, H6, Chlor-Xtra) and the others were regular hypochlorites at increasing concentrations (1%, 2%, 4%, 5.25%, <6%, 6% NaOCl) from different brands. The dentin blocks were exposed to the solutions for 2, 5, and 20 min at 20 °C, 37 °C and 45 °C, respectively. The depth of NaOCl penetration was determined by bleaching of the stain and measured by light microscopy at 20x and 40x. Statistical comparisons were made by using a generalized linear model with Bonferronis post-hoc correction. The shortest penetration (81±6.6 μm) was obtained after incubation in 1% NaOCl for 2 min at 20 °C; the highest penetration (376.3±3.8 μm) was obtained with Chlor-Xtra for 20 min at 45 °C. Varying NaOCl concentration produced a minimal effect while temperature and exposure time had a significant direct relationship with NaOCl penetration into dentinal tubules, especially those with lowered surface tension. The exposure time and temperature of sodium hypochlorite as well as the addition of surfactants may influence the penetration depth of irrigants into dentinal tubules.

Stage-specific therapeutic strategies of medication-related osteonecrosis of the jaws: a systematic review and meta-analysis of the drug suspension protocol

ObjectiveThe most debated topic about medication-related osteonecrosis of the jaws (MRONJ) is its therapy, as there are no definitive guidelines. The aims of this systematic review were (a) to outline the best therapeutic approach according to the stage at diagnosis and (b) to perform a meta-analysis to assess whether the drug-holiday protocol may be or not an effective method in the management of MRONJ patients.Materials and methodsThe systematic review was performed following the PRISMA principles. Results were screened according to inclusion and exclusion criteria regarding staging before/after treatment, follow-up, and information provided by the authors. For statistical analysis, linear variables are reported as means and standard deviations, medians, and inter-quartile range (IQR); normality of data, according to the distribution of complete healing (primary outcome variable), was assessed with the Kolmogorov-Smirnov test. A p value < 0.05 was considered statistically significant for all tests.ResultsThirteen studies were selected out of 1480. None of them was case-controlled or randomized. Conservative approach showed good results at early stages, but heterogeneous result at advanced stages (100% stage 0, stage I range 81–97%, stage II range 63.6–100%, stage III 73%). Surgical approach showed heterogeneous results at all stages (stage I range 0–100%, stage II range 52–100%, stage III range 50–100%). Statistical analysis showed a significantly higher prevalence of completely healed sites in patients who followed the drug-holiday protocol.ConclusionsThe results suggest that the current stage-specific approach for MRONJ therapy is based on a sound clinical rationale. Conservative treatment appears to yield better outcomes at early stages, while further investigations are needed to elucidate the best protocols for the management of advanced stages. The drug-holiday protocol statistically promotes complete healing after oral surgery procedures but the application should be dictated by the condition of each patient.Clinical relevanceAt present, early MRONJ stages should be primarily treated by means of a conservative approach while more advanced stages must be carefully evaluated. Individual decisions should be made for every single case even with respect to the drug-holiday protocol.

Influence of Platform-Switched, Laser-Microtextured Implant on Marginal Bone Level: A 24-Month Case Series Study.

PURPOSE The aim of this case series study was to evaluate clinical and radiographic changes of soft and hard tissues around tapered, platform-switched, laser-microtextured implants 24 months after crown placement. MATERIALS AND METHODS Twenty tapered, platform-switched, laser-microtextured collar implants were placed in 20 patients. Full-mouth plaque score, full-mouth bleeding score, probing depth, and mucosal recession were recorded at the time of crown cementation and after 24 months follow-up. The marginal bone-level changes at the mesial and distal aspects of the implants were calculated by subtracting from baseline and 24-month implant marginal bone level. RESULTS In terms of the full-mouth plaque score and full-mouth bleeding score, tapered, platform-switched, laser-microtextured implants showed statistically significant improvements at 6 months when compared to baseline (P < .001). Statistically significantly deeper probing depths (P < .001) were found when comparing baseline and at 24 months at mesial, lingual, and distal sites. However, no statistically significant difference was found at the buccal aspects (P = .064). Radiographic marginal bone loss at 2-year follow-up for tapered, platform-switched, laser-microtextured implants was 0.72 ± 0.16 mm and 0.67 ± 0.15 mm at the mesial and distal sites, respectively. CONCLUSION Within the limits of this study, tapered, platform-switched, laser-microtextured implants maintained marginal bone level (less than 1 mm radiographic bone loss) as well as limited mucosa recession over a 2-year period.

Comparison of three different crown-lengthening procedures in the maxillary anterior esthetic regions.

OBJECTIVE A papilla preservation crown-lengthening procedure (PPCL) was proposed for treatment of the maxillary anterior teeth (canine to canine) and compared to two traditional techniques. METHOD AND MATERIALS Thirty patients were assigned to three treatment groups: PPCL, the apically positioned flap with buccal approach (APF-B), and the apically positioned flap with buccal and palatal approach (APF-BP). Several clinical parameters were recorded at baseline and 6 months after surgery. RESULTS Although no statistically significant differences were reported in many of the clinical parameters examined, APF-B and APF-BP showed a significantly higher interproximal clinical attachment loss when compared to PPCL. In the PPCL group, there was a significant increase in esthetic appraisal by the patients. CONCLUSION Crown lengthening using a papilla-preservation flap approach and osseous recontouring is a viable alternative approach and could be useful in esthetic regions.

Rehabilitation of Full-Mouth Edentulism: Immediate Loading of Implants Inserted With Computer-Guided Flapless Surgery Versus Conventional Dentures: A 5-Year Multicenter Retrospective Analysis and OHIP Questionnaire.

Objective: The purpose of this report is to compare satisfaction of patients rehabilitated with full-mouth fixed prostheses using computer-aided flapless implant placement and immediate loading with patients rehabilitated with conventional removable prostheses. Materials and Methods: The study included 30 consecutive fully edentulous patients who received 312 implants and 30 matched controls treated with conventional removable prostheses. Mandible and maxilla were treated in the same surgical session with computer-guided flapless approach using NobelGuide protocol. Prefabricated screw-retained fixed prostheses were inserted at the end of surgery. Clinical and radiographic evaluations were assessed at 6, 12, and 36 months. At baseline and 5 years after prostheses delivery, patients answered OHIP-EDENT questionnaire (Oral Health Impact Profile for Edentulous subjects) to assess satisfaction. Results: The implant survival rate was 97.9%, whereas the average marginal bone loss was 1.9 ± 1.3 mm after 3 years. At 6 months, patients showed significantly greater satisfaction with their fixed rehabilitation as compared to conventional dentures. Conclusions: The results of this study confirm that rehabilitation with a prefabricated fixed prosthesis supported by implants placed with NobelGuide protocol significantly increases the quality of life in fully edentulous patients when compared with complete dentures.