Disease resolution following treatment of peri-implant diseases: A systematic review.

The aim of this PRISMA-compliant systematic review was to analyze the evidence pertaining to disease resolution after treatment of peri-implant diseases (PROSPERO: CRD42022306999) with the following PICO question: what is the rate of disease resolution following non-surgical and surgical therapy for peri-implant diseases in adult human subjects? A literature search to identify studies that fulfilled a pre-established eligibility criteria was conducted. Data on primary therapeutic outcomes, including treatment success, rate of disease resolution and/or recurrence, as well as a variety of secondary outcomes was extracted and categorized. Fifty-five articles were included. Few studies investigated the efficacy of different non-surgical and surgical therapies to treat peri-implant diseases using a set of pre-defined criteria and with follow-up periods of at least one year. The definition of treatment success and outcomes of disease resolution differed considerably among the included studies. Treatment of peri-implant mucositis was most commonly reported to be successful in arresting disease progression for ≤60% of the cases, whereas most studies on peri-implantitis treatment reported disease resolution occurring in <50% of the fixtures. In conclusion, disease resolution is generally unpredictable and infrequently achieved after the treatment of peri-implant diseases. A great variety of definitions have been used to define treatment success. Notably, percentages of treatment success and disease resolution were generally underreported. The use of standardized parameters to evaluate disease resolution should be considered an integral component in future clinical studies.

Influence of keratinized mucosa on the surgical therapeutical outcomes of peri-implantitis.

AIM: To assess the impact of keratinized mucosa (KM) width around dental implants on surgical therapeutic outcomes when treating peri-implantitis. MATERIAL AND METHODS: Surgically treated peri-implantitis implants were divided into two groups (KM width < 2 mm and ≥2 mm). Retrospective data were obtained after implant placement (T0) and the day of peri-implantitis surgical treatment (T1). Patients were later recruited (≥1 year after T1) for clinical and radiographic examination (T2). Outcomes were analysed using generalized estimating equation (GEE) models. RESULTS: A total of 40 patients (68 implants) (average follow-up: 52.4 ± 30.5 months) were included in this study. From T0 to T1, no differences were found between KM groups in terms of peri-implant probing depths (PPD) and bleeding on probing (BOP). However, sites with <2 mm KM exhibited significantly higher suppuration (SUP) and lower marginal bone level (MBL) (p > .01). Between T1 and T2, no major differences were noted on PPD reduction, BOP and MBL changes between the two groups. GEE modelling demonstrated that MBL severity prior to surgical therapy was a better predictor for implant survival than KM width. CONCLUSION: Surgical outcome in treating peri-implantitis was influenced by the severity of bone loss present at the time of treatment and not by the presence of KM at the time of treatment.

Outcomes of root resection therapy up to 16.8 years: A retrospective study in an academic setting.

BACKGROUND: Root resection has been considered a viable treatment option for molars with furcation defects. However, need of a multidisciplinary approach could potentially deem this procedure less successful. The aim of the present article was to determine survival rates of root resection procedure and reasons for failure in an academic setting. METHODS: Patient-related demographic data, medical history information, and relevant data pertaining to the root-resected teeth performed from January 1990 to September 2017 were reviewed through electronic and paper chart. Survival rates were analyzed using Kaplan-Meier estimate. Association between the reasons for failure and independent variables was established by a Pearson Chi-squared and Kruskal-Wallis test. RESULTS: A total of 85 patients with an average follow-up of 5 ± 4.3 years (range: 1 to 16.8 years) were included in the present article. A total of 47 molar teeth treated with root resection remained as part of the dentition (55.3%) and 38 (44.7%) failed. The mean survival time with the Kaplan-Mayer analysis was 109.9 months (9.1 years). Fracture (39.5%), caries (26.3%), and periodontal disease (23.7%) were the most common causes for failure. Interestingly, the majority of failures occurred in the first 4 years after therapy (n = 31; 81.5% of all failures). CONCLUSIONS: Root resection therapy remains a treatment solution for molars with furcation defects. In an academic setting, >50% of teeth remained functional after 9 years of root resection therapy.

Characterization of macrophages infiltrating peri-implantitis lesions.

OBJECTIVES: The mechanisms involved in the initiation and progression of peri-implantitis lesions are poorly understood. It was the aim to determine the content and activation status of macrophages present in human peri-implantitis lesions and compare the current findings with the macrophage polarization associated with periodontitis lesions. MATERIAL AND METHODS: A total of 14 patients were studied in this investigation. Seven were soft tissue biopsies from dental implants affected by peri-implantitis that required explantation. Seven biopsies were from chronic periodontal disease. Immunofluorescence stains were performed using biomarkers to identify macrophages (CD68+ ) undergoing M1 polarization (iNOS+ ) and M2 polarization (CD206+ ), along with Hoechst 33,342 to identify DNA content. All samples were stained and photographed, and double-positive cells for CD68 and iNOS or CD68 and CD206 were quantified. RESULTS: All peri-implantitis biopsies examined revealed a mixed population of macrophages undergoing M1 polarization and M2 polarization. Further analysis demonstrated the co-expression of iNOS and CD206, which indicates the presence of a heterogenic immune response on peri-implantitis lesions. Macrophage polarization in peri-implantitis lesions presents a distinct pattern than in periodontitis. We observed a significant increase in the population of M1 macrophages on peri-implantitis samples compared to periodontal disease samples. CONCLUSION: Our results demonstrate that peri-implantitis has higher numbers of macrophages displaying a distinct macrophage M1 polarization signature compared to periodontitis lesions. This pattern may explain, in part, the distinct nature of peri-implantitis progression vs. periodontitis in humans.

Characterization of macrophage polarization in periodontal disease.

AIM: To explore the M1/M2 status of macrophage polarization from healthy, gingivitis, and periodontitis patient samples. MATERIALS AND METHODS: Gingival biopsies were collected from 42 individuals (14 gingivitis, 18 periodontitis, and 10 healthy samples) receiving periodontal therapy. Histomorphology analysis was performed with haematoxylin and eosin staining. Immunofluorescence was performed using a combination of CD68 (macrophages), iNOS (M1), and CD206 (M2) in order to acquire changes in macrophage polarization at a single-cell resolution. Macrophages were quantified under microscopy using narrow wavelength filters to detect Alexa 488, Alexa 568, Alexa 633 fluorophores, and Hoechst 33342 to identify cellular DNA content. RESULTS: Gingivitis and periodontitis samples showed higher levels of macrophages compared with healthy samples. Unexpectedly, periodontitis samples displayed lower levels of macrophages dispersed in the stromal tissues compared with gingivitis samples; however, it remained higher than healthy tissues. The polarization of macrophages appears to be reduced in periodontitis and showed similar levels to those observed in healthy tissues. CONCLUSIONS: Our study found that gingivitis and periodontitis differ from each other by the levels of macrophage infiltrate, but not by changes in macrophage polarization.

Decision Making for Management of Periimplant Diseases.

INTRODUCTION: Nonsurgical and surgical management of periimplant mucositis and periimplantitis have shown promising results in arresting periimplant marginal bone loss (MBL) and preventing implant loss. However, management of periimplant diseases still remains unpredictable for full reconstruction of lost tissues and completely arrests disease progression. The present study proposes a decision tree that compiles both clinical and radiographic presentation of failing implants to aid in the decision making for their management. MATERIALS AND METHODS: An extensive literature review was performed using 3 electronic databases (PubMed, Ovid MEDLINE, and Cochrane Central) on the most recent treatment modalities for the management of periimplant diseases. DISCUSSION: Evidence-based treatment suggestions were primarily derived from periimplant defect morphology, presence, and severity of periimplant MBL. More evidence is required supporting soft-tissue augmentation for the treatment of periimplant diseases. CONCLUSION: Management of periimplant diseases can include lasers, mechanical instrumentation, chemical detoxification, and antimicrobial agents for nonsurgical approaches. On the other hand, removal of failing implants, resective surgery, guided bone regeneration, and soft-tissue grafting are presented as valid options for the surgical treatment of periimplantitis.

Assessment of Marginal Bone Loss around Platform-Matched and Platform-Switched Implants - A Prospective Study

Abstract The aim of the present study was to perform a software-assisted radiographic assessment of the effect of platform-switching on marginal bone loss (MBL) around dental implants. Forty patients requiring a dental implant in non-grafted partially edentulous mandibles were enrolled and categorized into implants receiving a platform-matched abutment (control group) or implants with a platform-switched abutment (test group). Standardized digital periapical radiographs were taken at the time of implant placement (T0), at implant loading (T1) and 1-year after functional loading (T2). Software-assisted radiographic assessment of the MBL horizontal, vertical and area changes was performed and compared between time intervals (T1-T0, T2-T1 and T2-T0). Mean radiographic horizontal MBL (hMBL) and vertical MBL (vMBL) from implant placement to 1-year after implant loading (T2-T0) were significantly increased around platform-matched when compared to platform-switched abutments (1.04 mm vs 0.84 mm, p<0.05) and (0.99 mm vs 0.82 mm, p<0.05), respectively. Additionally, bone loss area (BLa) was greater (0.77 mm2 vs 0.63 mm2; p<0.05) for platform-matched compared to platform-switched abutments. Platform-switching has a positive impact upon the amount of bone modeling after loading implants with internal hexagon connection.

Resumo O objetivo do presente estudo foi realizar uma avaliação radiográfica assistida por computador do efeito da plataforma reduzida sobre a perda óssea marginal (MBL) ao redor de implantes. Quarenta pacientes que necessitavam um implante em mandíbulas parcialmente edêntulas não enxertadas foram selecionados e divididos em implantes que receberam pilares de plataforma igualada (grupo controle) ou implantes com pilares de plataforma reduzida (grupo teste). Radiografias periapicais digitais padronizadas foram realizadas no momento da instalação do implante (T0), carregamento do implante (T1) e 1 ano após carregamento funcional (T2). Avaliação radiográfica assistida por computador da MBL horizontal, vertical e mudanças de área foi realizada e comparada entre os intervalos de tempo (T1-T0, T2-T1 e T2-T0). A média radiográfica da MBL horizontal (hMBL) e da MBL vertical (vMBL) do momento da instalação do implante até 1 ano após carregamento (T2-T0) foram significativamente aumentadas ao redor dos pilares de plataforma igualada quando comparado com os pilares de plataforma reduzida (1,04 mm vs 0,84 mm, p<0,05) e (0,99 mm vs 0,82,mm, p<0,05), respectivamente. Além disso, a área de perda óssea (BLa) foi maior (0,77 mm2 vs 0,63 mm2; p<0,05) para plataforma igualada comparada com pilares de plataforma reduzida. Plataforma reduzida tem um impacto positivo na remodelação óssea após carregamento de implantes com conexão interna hexagonal.

Protein biomarkers and microbial profiles in peri-implantitis.

OBJECTIVES: The aim of the present investigation was to determine the profile of peri-implant crevicular fluid (PICF) biomarkers combined with microbial profiles from implants with healthy peri-implant tissues and peri-implantitis to assess real-time disease activity. MATERIAL AND METHODS: Sixty-eight patients were included in this cross-sectional study. They were divided into two groups: 34 patients with at least one healthy implant (control) and 34 with at least one peri-implantitis affected implant (test). Total DNA content and qPCR analysis for periodontal bacteria obtained from subgingival plaque samples (Aggregatibacter actinomycetemcomitans, Prevotella intermedia, Porphyromonas gingivalis, Tannerella forsythia, and Treponema denticola) and a PICF analysis for IL-1ß, VEGF, MMP-8, TIMP-2, and OPG were performed. The individual and combined diagnostic ability of each biomarker for peri-implantitis and target bacterial species were analyzed. RESULTS: The mean concentration of IL-1ß (44.6 vs. 135.8 pg/ml; P < 0.001), TIMP-2 (5488.3 vs. 9771.8 pg/ml; P = 0.001), VEGF (59.1 vs. 129.0 pg/ml; P = 0.012), and OPG (66.5 vs. 111.7 pg/ml; P = 0.050) was increased in the peri-implantitis patients. The mean expression of MMP-8 (6029.2 vs. 5943.1 pg/ml; P = 0.454) and did not reveal a meaningful difference among groups. Total bacterial DNA of selected microorganisms was associated with a threefold or greater increase in peri-implantitis although no statistical significant difference. The ability to diagnose diseased sites was enhanced by T. denticola combined with IL-1ß, VEGF, and TIMP-2 PICF levels. CONCLUSION: The present data suggest that the increased levels of the selected PICF-derived biomarkers of periodontal tissue inflammation, matrix degradation/regulation, and alveolar bone turnover/resorption combined with site-specific microbial profiles may be associated with peri-implantitis and could have potential as predictors of peri-implant diseases.

Implant success remains high despite grafting voids in the maxillary sinus.

OBJECTIVES: Given that the nature and presence of voids present within grafted sinuses following maxillary sinus elevation procedures were not known, nor was the contribution of these factors to implant success, the purpose of this study was to investigate these parameters and their relationship to implant success. MATERIALS AND METHODS: This study evaluated data from 25 subjects who had a lateral window maxillary sinus augmentation procedure. Cone-beam computed tomography (CBCT) was performed at baseline and 4 months after surgery. CBCT images were used to evaluate grafted sites prior to implant placement. Using CBCT images, three examiners independently measured bone-grafted areas (BG), void areas (V), and percentage of void areas (V%) from six different sections within grafted sites. The six sections were defined as a cross-sectional (CS) midpoint, CS mesial point, CS distal point, horizontal section (HS) low point, HS midpoint, and HS high point. Implant success was also determined. RESULTS: The calculated V% (V/BG) for the CS midpoint, CS mesial point, CS distal point, HS low point, HS midpoint, and HS high point were 5.30 ± 6.67%, 5.79 ± 8.51%, 6.67 ± 7.12%, 2.07 ± 2.56%, 5.30 ± 6.62%, and 4.92 ± 5.17% respectively. Implant success after 6 months of follow-up approximated 100%. CONCLUSIONS: Although voids within grafts varied in terms of distribution and size, the V% within the HS low point were significantly smaller compared to those within the CS midpoint and CS distal point, which had the most intra-subject V%. Thus, more attention should be given to the distal aspect of the sinus when compacting graft materials in the lateral wall sinus augmentation procedure. Implant success was not influenced by the existence of voids as implant success remained high.