Periodontists and oral surgeons' peri-implantitis-related education, knowledge, attitudes, and professional behavior: A national survey

OBJECTIVES

Each year, approximately 5 million dental implants are placed in the United States and one out of three patients is likely to experience peri-implantitis (PI). The objectives were to compare the PI-related education, knowledge, attitudes, and professional behavior of periodontists and oral maxillofacial surgeons (OMS), and to explore relationships between these constructs of interest.

METHODS

A total of 389 periodontists and 161 OMS responded to a web-based survey. Descriptive and inferential statistical analyses (independent sample t-tests, chi-square tests, and correlational analyses) were conducted.

RESULTS

On average, periodontists reported a higher percentage of time spent in residency on implant surgery (21.02% vs. 7.27%; p < 0.001), better education about PI (5-point scale with 1 = not at all well: means: 2.86 vs. 2.59; p < 0.001), and better knowledge of risk factors (4.07 vs. 3.86; p < 0.001) than OMS. Periodontists argued that oral hygiene-related treatment (4.45 vs. 4.22; p = 0.001) and regeneration-focused treatments such as guided tissue regeneration (3.62 vs. 3.20; p < 0.001) contributed more to successfully treating PI and used these treatments more in their practices (4.86 vs. 4.56; p < 0.001/3.06 vs. 2.68; p < 0.001) than OMS. They also considered PI as a more serious problem than OMS (4.55 vs. 3.80; p < 0.001). The better the respondents' PI-related knowledge was, the more they considered PI as a serious problem (r = 0.19; p < 0.001). The more cases they treated per month, the more they considered PI as a serious problem (r = 0.19; p < 0.001).

CONCLUSIONS

The results of the present study highlight the lack of standardization in the specialty training of periodontists and OMS. Best practice guidelines for the diagnosis and treatment of PI are needed to optimize graduate education about this important topic.

[Non-surgical peri-implantitis treatment with or without systemic antibiotics]

This study investigated the effect of initial nonsurgical treatment in patients with peri-implantitis with or without prescription of an antibiotic regimen consisting of amoxicillin and metronidazole. For this purpose, patients with peri-implantitis were randomized into a group of initial treatment with antibiotics and a group without antibiotics. They were re-evaluated 12 weeks after treatment. Analyses were performed at the patient level at 1 peri-implant pocket per patient. Both groups showed significant peri-implant pocket depth reductions after initial treatment. Treatment with antibiotics resulted in a higher mean reduction in peri-implant pocket depth than when no antibiotics were used, but this difference did not reach statistical significance. Only 2 implants, 1 in each group, showed a successful outcome of a peri-implant pocket depth ofunder ≤ 5 mm and with an absence of bleeding and pus after probing. Initial treatment with or without antibiotics is ultimately not sufficient to fully treat peri-implantitis; additional surgical procedures will often be required.

Non-surgical peri-implantitis treatment with or without systemic antibiotics; a randomized controlled clinical trial

Objectives

To assess the adjunctive effect of systemic amoxicillin (AMX) and metronidazole (MTZ) in patients receiving non‐surgical treatment (NST) for peri‐implantitis (PI).

Materials and methods

Thirty‐seven patients were randomized into an experimental group treated with NST plus AMX + MTZ (N = 18) and a control group treated with NST alone (N = 19). Clinical parameters were evaluated at 12 weeks post‐treatment. The primary outcome was the change in peri‐implant pocket depth (PIPD) from baseline to 12 weeks, while secondary outcomes included bleeding on probing (BoP), suppuration on probing (SoP), and plaque. Data analysis was performed at patient level (one target site per patient).

Results

All 37 patients completed the study. Both groups showed a significant PIPD reduction after NST. The antibiotics group showed a higher mean reduction in PIPD at 12 weeks, compared with the control group (2.28 ± 1.49 mm vs. 1.47 ± 1.95 mm), however, this difference did not reach statistical significance. There was no significant effect of various potential confounders on PIPD reduction. Neither treatment resulted in significant improvements in BoP at follow‐up; 30 of 37 (81%) target sites still had BoP after treatment. Only two implants, one in each group, exhibited a successful outcome defined as PIPD < 5 mm, and absence of BoP and SoP.

Conclusions

Non‐surgical treatment was able to reduce PIPD at implants with PI. The adjunctive use of systemic AMX and MTZ did not show statistically significant better results compared to NST alone. NST with or without antibiotics was ineffective to completely resolve inflammation around dental implants.

Risk factors, diagnosis and treatment of peri-implantitis: A cross-cultural comparison of U.S. and European periodontists' considerations

BACKGROUND

Peri-implantitis (PI) is a growing concern in the dental community worldwide. The study aimed to compare U.S. vs. European periodontists' considerations of risk factors, diagnostic criteria, and management of PI.

MATERIALS AND METHODS

393 periodontists from the U.S. and 100 periodontists from Europe (Germany, Greece, Netherlands) responded to anonymous surveys electronically or by mail.

RESULTS

Compared to U.S. periodontists, European respondents were younger, more likely to be female and placed fewer implants per month (9.12 vs. 13.90;p = 0.003). Poor oral hygiene, history of periodontitis, and smoking were considered as very important risk factors by both groups (rated >4 on 5-point scale). European periodontists rated poor oral hygiene (4.64 vs. 4.45;p = 0.005) and history of periodontitis (4.36 vs. 4.10;p = 0.006) as more important and implant surface (2.91 vs. 3.18;p = 0.023), occlusion (2.80 vs. 3.75;p<0.001) and presence of keratinized tissue (3.27 vs. 3.77;p<0.001) as less important than did U.S. periodontists. Both groups rated clinical probing, radiographic bone loss, and presence of bleeding and suppuration as rather important diagnostic criteria. They rated implant exposure/mucosal recession as relatively less important with U.S. periodontists giving higher importance ratings than European periodontists (3.99 vs. 3.54;p = 0.001). Both groups nearly always used patient education, plaque control and mechanical debridement when treating PI. U.S. periodontists were more likely to use antibiotics (3.88 vs. 3.07;p<0.001), lasers (2.11 vs. 1.68;p = 0.005), allograft (3.39 vs. 2.14;p<0.001) and regenerative approaches (3.57 vs. 2.56;p<0.001), but less likely to use resective surgery (3.09 vs. 3.53;p<0.001) than European periodontists.

CONCLUSIONS

U.S. and European periodontists' considerations concerning risk factors, diagnosis and management of PI were evidence-based. Identified differences between the two groups can inform future educational efforts. This article is protected by copyright. All rights reserved.

Submucosal microbiome of peri-implant sites: A cross-sectional study

AIM

To study the peri-implant submucosal microbiome in relation to implant disease status, dentition status, smoking habit, gender, implant location, implant system, time of functional loading, probing pocket depth (PPD), and presence of bleeding on probing.

MATERIALS AND METHODS

Biofilm samples were collected from the deepest peri-implant site of 41 patients with paper points, and analysed using 16S rRNA gene pyrosequencing.

RESULTS

We observed differences in microbial profiles by PPD, implant disease status, and dentition status. Microbiota in deep pockets included higher proportions of the genera Fusobacterium, Prevotella, and Anaeroglobus compared with shallow pockets that harboured more Rothia, Neisseria, Haemophilus, and Streptococcus. Peri-implantitis (PI) sites were dominated by Fusobacterium and Treponema compared with healthy implants and peri-implant mucositis, which were mostly colonized by Rothia and Streptococcus. Partially edentulous (PE) individuals presented more Fusobacterium, Prevotella, and Rothia, whereas fully edentulous individuals presented more Veillonella and Streptococcus.

CONCLUSIONS

PPD, implant disease status, and dentition status may affect the submucosal ecology leading to variation in composition of the microbiome. Deep pockets, PI, and PE individuals were dominated by Gram-negative anaerobic taxa.

Surgical treatment of peri-implantitis defects with two different xenograft granules: A randomized clinical pilot study

Objectives

To investigate whether xenograft EB (EndoBon) is non‐inferior to xenograft BO (Bio‐Oss) when used in reconstructive surgery of peri‐implant osseous defects.

Materials and methods

Dental patients with one implant each demonstrating peri‐implantitis were randomized to receive surgical debridement and defect fill with either BO or EB. Changes in bone level (BL) and intrabony defect depth (IDD) evaluated radiographically were the primary outcomes. The secondary outcomes included changes in probing pocket depth (PPD), bleeding on probing (BoP), and suppuration on probing (SoP). All outcomes were recorded before treatment and at 6 and 12 months post‐treatment.

Results

Twenty‐four patients (n = 11 BO, n = 13 EB) completed the study. Both groups demonstrated significant within‐group improvements in all clinical and radiographic parameters at 6 and 12 months (p ≤ .001). At 12 months, both groups presented with IDD reductions of 2.5–3.0 mm on average. The inter‐group differences were not statistically significant at all time points and for all the examined parameters (p > .05). While the radiographic defect fill in both groups exceeded > 1 mm and can be considered treatment success, successful treatment outcomes as defined by Consensus Reporting (no further bone loss, PPD ≤ 5 mm, no BOP, and no SoP) were identified in 2/11 (18%) BO and 0/13 (0%) EB individuals (Fisher's exact test, p = .199).

Conclusions

Within the limitations of this pilot study, the application of xenograft EB showed to be non‐inferior to xenograft BO when used in reconstructive surgery of peri‐implant osseous defects.

Occlusal Migration of Teeth Adjacent to Implant Prostheses in Adults: A Long-Term Study

PURPOSE

To evaluate the effect of continuous tooth eruption on the outcomes of single-implant-supported restorations in the anterior maxilla of adults.

MATERIALS AND METHODS

Seventy-six patients (age: 21 to 78 years) treated with single-implant-supported restorations in the esthetic zone were included. Radiographs obtained at crown placement and follow-up examinations from 1 to 15 years postloading were analyzed with regard to vertical incisal plane changes of the implant-supported crown relative to adjacent teeth.

RESULTS

Infraocclusion increased over time by 0.08 ± 0.02 mm/year. Infraocclusion was more pronounced (P = .04) for delayed (0.09 mm/year) versus immediate implant placement (0.06 mm/year) and for younger versus older adults (0.0013 mm/year per additional year of age; P = .014). No statistically significant association between infraocclusion and sex, ethnicity, implant site, timing of implant temporization, surgical protocol, and type of restoration was found.

CONCLUSION

Infraocclusion of single-implant-supported maxillary anterior restorations may result in esthetic concerns over time. Greater infraocclusion occurs in delayed implant placement and in younger individuals.

Stem cell therapy for reconstruction of alveolar cleft and trauma defects in adults: A randomized controlled, clinical trial

BACKGROUND

Stem cell therapy with bone marrow-derived mesenchymal stem cells is a promising tissue engineering strategy to promote regeneration of craniofacial bone.

PURPOSE

To determine whether cell therapy with ex vivo expanded stem cell populations would be safe and efficacious in the regeneration of large alveolar defects in patients with a history of cleft palate or craniofacial trauma.

MATERIALS AND METHODS

Eighteen patients (10 patients with traumatic injury and 8 patients with cleft palate) presenting with missing teeth associated with horizontal alveolar bone deficiencies were included in this randomized controlled clinical trial. Patients were randomized to receive either conventional autogenous block grafts or stem cell therapy. After a healing period of 4 months the treated sites were re-entered and the bone width re-assessed prior to implant placement. Implant stability was evaluated through torque testing of the implant upon insertion and at 6 months postloading.

RESULTS

The mean gain in bone width was 1.5 ± 1.5 mm in the stem cell therapy group and 3.3 ± 1.4 mm in the control group. Overall, bone gain was higher in trauma patients as compared to patients with cleft palate, for both the control and the stem cell therapy groups. Most postoperative complications were wound dehiscences and incision line openings. Implants were placed successfully in 5 out of 10 patients in the stem cell therapy group and in all 8 patients in the control group. One implant from the control/cleft palate group failed before loading, while the rest of the implants were loaded successfully and remained stable at 6 months. The patients who did not receive implants were re-treated with autogenous block bone graft.

CONCLUSION

The ability of stem cells to treat large alveolar defects is safe, yet, their ability to completely reconstitute large alveolar defects is limited. This approach requires further optimization to meet the outcomes seen using current methods to treat large defects, particularly those resultant of cleft palate.

Bone Marrow Stromal Stem Cells in Tissue Engineering and Regenerative Medicine

Bone marrow stromal stem cells (BMSCs) are adult multipotent cells, which have the potential to differentiate into cell types of mesodermal origin, namely osteocytes, adipocytes, and chondrocytes. Due to their accessibility and expansion potential, BMSCs have historically held therapeutic promise in tissue engineering and regenerative medicine applications. More recently, it has been demonstrated that not only can bone marrow stromal stem cells directly participate in tissue regeneration, but they also have the capacity to migrate to distant sites of tissue injury, where they can participate in tissue repair either directly through their differentiation or indirectly through paracrine mechanisms. Additionally, they can elicit various immunomodulatory signals, which can attenuate the inflammatory and immune responses. As such, bone marrow stromal stem cells have been explored clinically for treatment of a wide variety of different conditions including bone defects, graft-vs.-host disease, cardiovascular diseases, autoimmune diseases, diabetes, neurological diseases, and liver and kidney diseases. This review provides an overview of current clinical applications of bone marrow stromal stem cells and discusses their therapeutic properties, while also addressing limitations of their use. PubMed, Ovid, and Google Scholar online databases were searched using several keywords, including "stem cells", "tissue engineering", tissue regeneration" and "clinical trials". Additionally, Clinical trials.gov was used to locate completed clinical trials using bone marrow derived stem cells.

The effect of blue light on periodontal biofilm growth in vitro

We have previously shown that blue light eliminates the black-pigmented oral bacteria Porphyromonas gingivalis, Prevotella intermedia, Prevotella nigrescens, and Prevotella melaninogenica. In the present study, the in vitro photosensitivity of the above black-pigmented microorganisms and four Fusobacteria species (Fusobacterium nucleatum ss. nucleatum, F. nucleatum ss. vincentii, F. nucleatum ss. polymorphum, Fusobacterium periodonticum) was investigated in pure cultures and human dental plaque suspensions. We also tested the hypothesis that phototargeting the above eight key periodontopathogens in plaque-derived biofilms in vitro would control growth within the dental biofilm environment. Cultures of the eight bacteria were exposed to blue light at 455 nm with power density of 80 mW/cm2 and energy fluence of 4.8 J/cm2. High-performance liquid chromatography (HPLC) analysis of bacteria was performed to demonstrate the presence and amounts of porphyrin molecules within microorganisms. Suspensions of human dental plaque bacteria were also exposed once to blue light at 455 nm with power density of 50 mW/cm2 and energy fluence of 12 J/cm2. Microbial biofilms developed from the same plaque were exposed to 455 nm blue light at 50 mW/cm2 once daily for 4 min (12 J/cm2) over a period of 3 days (4 exposures) in order to investigate the cumulative action of phototherapy on the eight photosensitive pathogens as well as on biofilm growth. Bacterial growth was evaluated using the colony-forming unit (CFU) assay. The selective phototargeting of pathogens was studied using whole genomic probes in the checkerboard DNA-DNA format. In cultures, all eight species showed significant growth reduction (p < 0.05). HPLC demonstrated various porphyrin patterns and amounts of porphyrins in bacteria. Following phototherapy, the mean survival fractions were reduced by 28.5 and 48.2% in plaque suspensions and biofilms, respectively, (p < 0.05). DNA probe analysis showed significant reduction in relative abundances of the eight bacteria as a group in plaque suspensions and biofilms. The cumulative blue light treatment suppressed biofilm growth in vitro. This may introduce a new avenue of prophylactic treatment for periodontal diseases.