Current Emerging Concepts on the Pathogenesis of Peri-implant Diseases: A Narrative Review.

OBJECTIVES: The aim of this narrative review is to describe the emerging evidence concerning etiological factors and pathophysiological mechanisms involved in peri-implant inflammatory diseases. MATERIAL AND METHODS: An electronic search for articles published until November 2022 was conducted in MEDLINE by three independent reviewers to identify manuscripts reporting data on etiological factors and pathophysiological mechanisms associated with peri-implant diseases. RESULTS: Current evidence suggests that peri-implant mucositis and peri-implantitis are inflammatory conditions linked to a microbial challenge. However, in recent years, there has been increasing evidence indicating that certain peri-implant inflammatory conditions may not be primarily related to biofilm-mediated infectious processes but rather to other biological mechanisms, such as a foreign body response. CONCLUSION: The current evidence, not only in the dental literature, opens new avenues for a more complex interpretation of the etiopathogenetic factors involved in peri-implant diseases. A better understanding of various factors related to the host response, including dysbiosis mechanisms associated with changes in microbiota composition, is necessary for a more precise physiopathological characterization of these diseases.

Prevalence of Peri-Implant Mucositis, Peri-Implantitis and Associated Risk Indicators of Implants with and without Laser-Microgrooved Collar Surface: A Long-Term (≥20 Years) Retrospective Study.

The aim of the current study was to retrospectively investigate the prevalence of peri-implant mucositis (PIM) and peri-implantitis (P) in a long-term follow-up (≥20 years) of implants with the same body design and body surface but different collar surfaces with laser-microtextured grooves (LMGSs) vs. no laser-microtextured grooves (no-LMGSs) in private practice patients. Furthermore, several patient-related, implant-related, site-, surgical-, and prosthesis-related potential disease risk factors were analyzed. A chart review of patients receiving at least one pair of implants (one with an LMGS and the other without LMGS) in the period 1993-2002 was used. Chi-square analysis was used to determine if a statistically significant difference between the investigated variables and PIM/P was present. Possible risk factors were statistically evaluated by a binary logistic regression analysis. A total of 362 patients with 901 implant-supported restorations (438 with LMGS and 463 no-LMGS) were included in the study. The cumulative survival rates of implants at 5, 10, 15, and 20 years were 98.1%, 97.4%, 95.4%, and 89.8%, respectively, for the LMGS group, and 93.2%, 91.6%, 89.5%, and 78.3% for the no-LMGS group. The difference was statistically significant at all timepoints (p < 0.05). In total, at the end of the follow-up period, 45.7% of patients and 39.8% of implants presented PIM, and 15.6% of patients and 14% of implants presented P. A total of 164 LMGS implants (37.4%) and 195 no-LMGS implants (42.1%) presented peri-implant mucositis, while 28 (6.3%) of LMGS implants and 98 (21.1%) no-LMGS implants demonstrated peri-implantitis. Differences between LMGS implants and no-LMGS implants were statistically significant (p < 0.05). The binary logistic regression identified collar surface, cigarette smoking, histories of treated periodontitis, and lack of peri-implant maintenance as risk factors for P. After at least 20 years of function in patients followed privately, LMGS implants compared to no-LMGS implants presented a statistically and significantly lower incidence of P. Implant collar surface, cigarette smoking, previously treated periodontitis, and lack of peri-implant maintenance are factors with significant association to P.

Effects of maintenance implant therapy with and without periodic removal and decontamination of prosthetic components on inflammatory peri-implant parameters.

This retrospective clinical study compared two different professional maintenance therapy (MT) approaches (with and without periodic removal and decontamination of prosthetic components) on peri-implant inflammatory clinical and biochemical parameters after 5 years of implant function. A retrospective analysis based on patient records was used to assess inflammatory clinical and biochemical parameters around dental implants placed by the same clinician in a private practice. The Plaque Index (PI), peri-implant probing depth (PPD), mucosal recession (REC), bleeding on probing (BOP), and radiographic marginal bone level were determined at baseline and at each follow-up year. Moreover, at the last follow-up visit, the peri-implant intrasulcular levels of active metalloproteinasis 8 (aMMP-8) were also assessed. All participants were under MT with a 6-month recall interval. A total of 92 patients with 132 implants were selected. At the end of the study period, 12 patients with 12 implants were classified as dropouts. The remaining 80 patients and 120 implants were classified into two groups: Group 1 (42 patients, 62 implants) received MT with periodic removal and decontamination of prosthetic components; Group 2 (38 patients, 58 implants) received MT without periodic removal and decontamination of prosthetic components. No statistical differences were found between the groups regarding PI, PPD, and REC. Group 1 presented a statistically significant higher number of sites with BOP (12.4% vs 6.2%). Marginal bone loss was statistically higher in Group 2 than in Group 1 (0.23 ± 0.6 mm vs 0.78 ± 0.3 mm). Intrasulcular levels of aMMP-8 were statistically higher in Group 1 than in Group 2. The supplemental application of periodic removal and decontamination of prosthetic components during MT had a significantly positive effect on the inflammatory status of peri-implant tissues.

Can Peri-Implant Marginal Bone Loss Progression and a-MMP-8 Be Considered Indicators of the Subsequent Onset of Peri-Implantitis? A 5-Year Study.

The aim of this retrospective study was to investigate the relationship between the amount of early bone remodeling, the marginal bone loss (MBL) progression, and the peri-implant sulcular fluid concentration of active metalloproteinase-8 (a-MMP-8) and the incidence of peri-implantitis (P) over 5 years of implant function. It has been documented that dental implants with a high degree of early marginal bone loss (MBL) are likely to achieve additional increased MBL during function. Moreover, it has been speculated that early increased MBL might be a predictive factor for the subsequent onset of peri-implant inflammatory diseases. Clinical and radiographic data at implant placement (T0) and restoration delivery (TR) at 6 months (T1), 2 years (T2), and 5 years (T5) post-loading were retrospectively collected. MBL levels/rates (MBLr) and peri-implant sulcular fluid levels/rates of a-MMP-8 were assessed at TR, T1, T2, and T5. Implants were divided into two groups: group 1 with peri-implantitis (P+) and group 2 without peri-implantitis (P−). A multi-level simple binary logistic regression, using generalized estimation equations (GEEs), was implemented to assess the association between each independent variable and P+. A receiver operating characteristics (ROC) curve was used to evaluate an optimal cutoff point for T1 MBL degree and a-MMP-8 level to discriminate between P+ and P− implants. A total of 80 patients who had received 80 implants between them (39 implants with a laser-microtextured collar surface (LMS) and 41 implants with a machined collar surface (MS)) were included. Periapical radiographs and a software package were used to measure MBL rates. Peri-implant sulcular implant fluid samples were analyzed by a chairside mouth-rinse test (ImplantSafe®) in combination with a digital reader (ORALyzer®). Twenty-four implants (six with an LMS and eighteen with an MS) were classified as P+. No statistically significant association was found between the amount of early bone remodeling, MBL progression, and MBLr and the incidence of peri-implantitis. Implants with a-MMP-8 levels >15.3 ng/mL at T1 presented a significantly higher probability of P+. The amount of early marginal bone remodeling cannot be considered as an indicator of the subsequent onset of P, whereas high a-MMP-8 levels 6 months after loading could have a distinct ability to predict P.

Use of Xenogenic Collagen Matrices in Peri-Implant Soft Tissue Volume Augmentation: A Critical Review on the Current Evidence and New Technique Presentation.

Plastic peri-implant surgical procedures aiming to increase soft tissue volume around dental implants have long been well-described. These are represented by: pedicle soft tissue grafts (rotational flap procedures and advanced flap procedures) and free soft tissue grafts (epithelialized, also called free gingival graft (FGG), and non-epithelialized, also called, connective tissue graft (CTG) or a combination of both. To bypass the drawback connected with autologous grafts harvesting, xenogenic collagen matrices (XCM)s and collagen-based matrices derived from porcine dermis (PDXCM)s have been introduced, as an alternative, in plastic peri-implant procedures. AIM: This review is aimed to evaluate and to critically analyze the available evidence on the effectiveness of XCMs and PDXCMs in soft tissue volume augmentation around dental implants. Moreover, a clinical case with a new soft tissue grafting procedure technique (Guided Soft Tissue Regeneration, GSTR) is presented. MATERIAL AND METHODS: An electronic search was performed on the MEDLINE database, SCOPUS, Cochrane Library and Web of Science. The electronic search provided a total of 133 articles. One hundred and twenty-eight not meeting the inclusion criteria were excluded. Seven articles of human randomized clinical trials were selected. A total number of 108 patients were treated with CTG, and 110 patients with XCM. RESULTS: in peri-implant soft tissue augmentation procedures, XCMs seem an effective alternative to CTGs, associated with lower patient morbidity and lower operative times.

Clinical, radiographic, and biochemical evaluation of two-piece versus one-piece single implants with a laser-microgrooved collar surface after 5 years of functional loading.

AIM: To compare the clinical and radiographic conditions and the expression of pro-inflammatory cytokines in peri-implant crevicular fluid (PICF) at two-piece/bone level (TP/BL) versus one-piece/tissue level (OP/TL) single implants with a laser-microgrooved collar after at least 5 years of loading. MATERIALS AND METHODS: In total, 20 single TP/BL implants and 20 contralateral OP/TL implants, both with a laser-microgrooved collar surface, in 20 systemically and periodontally healthy subjects (12 males and 8 females, between the age of 36 and 64 [mean age of 49.7 ± 12.3 years]), were examined. Levels of IL-1ß, IL-1RA, IL-6, IL-8, IL-17, b-FGF, G-CSF, GM-CSF, IFN, MIP-1ß, TNF-α, and VEGF were assessed in PICF using the Bio-Plex 200 Suspension Array System. Plaque index (PI), probing depth (PD), bleeding on probing (BOP), and gingival recession (REC) were recorded. Radiographic crestal bone levels (CBL) were assessed at the mesial and distal aspects of the implant sites. RESULTS: The mean PI, PD, BOP, and REC values had no significant differences in either group. A higher mean value of CBL with statistical difference was detected for TP/BL compared with OP/TL implants. The levels of IL-1ß, IL-6, IL-8, GM-CSF, and MIP-1ß and TNF-α were higher at TP/BL implants than at OP/TL implants. However, only IL-1ß, IL-6, and TNF-α values presented significant differences between the groups. CONCLUSIONS: Although after 5 years of loading single TP/BL and OP/TL implants with a laser-microgrooved collar surface presented similar good clinical conditions, a higher proinflammatory state and higher crestal bone loss were detected for TP/BL implants.

In Vitro Direct and Indirect Cytotoxicity Comparative Analysis of One Pre-Hydrated versus One Dried Acellular Porcine Dermal Matrix.

Aim: The aim of the present study was to compare the direct and indirect cytotoxicity of a porcine dried acellular dermal matrix (PDADM) versus a porcine hydrated acellular dermal matrix (PHADM) in vitro. Both are used for periodontal and peri-implant soft tissue regeneration. Materials and methods: Two standard direct cytotoxicity tests­namely, the Trypan exclusion method (TEM) and the reagent WST-1 test (4-3-[4-iodophenyl]-2-[4-nitrophenyl]-2H-[5-tetrazolio]-1,3-benzol-desulphonated)­were performed using human primary mesenchymal stem cells (HPMSCs) seeded directly onto a PDADM and PHADM after seven days. Two standard indirect cytotoxicity tests­namely, lactate dehydrogenase (LTT) and MTT (3-[4,5-dimethyl-2-thiazolyl]-2,5-diphenyl-2H-tetrazoliumbromide)­were performed using HPMSCs cultivated in eluates from the matrices incubated for 0.16 h (10 min), 1 h, and 24 h in a serum-free cell culture medium. Results: The WST and the TEM tests revealed significantly lower direct cytotoxicity values of HPMSCs on the PHADM compared with the PDADM. The indirect cytotoxicity levels were low for both the PHADM and PDADM, peaking in short-term eluates and decreasing with longer incubation times. However, they were lower for the PHADM with a statistically significant difference (p < 0.005). Conclusions: The results of the current study demonstrated a different biologic behavior between the PHADM and the PDADM, with the hydrated form showing a lower direct and indirect cytotoxicity.

Correlation between Peri-Implant Marginal Bone Loss Progression and Peri-Implant Sulcular Fluid Levels of Metalloproteinase-8.

OBJECTIVES: The aim of this retrospective study was to analyze peri-implant marginal bone loss levels/rates and peri-implant sulcular fluid levels/rates of metalloproteinase-8 in three timeframes (6 months post-surgery-restoration delivery (T0)-and 6 (T6) and 24 (T24)-months post-loading) and to evaluate if there is a correlation between peri-implant sulcular fluid levels of metalloproteinase-8 and peri-implant marginal bone loss progression. MATERIALS AND METHODS: Two cohorts of patients undergoing implant surgery between January 2017 and January 2019 were selected in this retrospective study. A total of 39 patients received 39 implants with a laser-microtextured collar surface, and 41 subjects received 41 implants with a machined/smooth surface. For each patient, periapical radiographs and a software package were used to measure marginal bone loss rates. Implant fluid samples were analyzed by an enzyme-linked immunosorbent assay (ELISA) test. The modified plaque index, probing depth, and bleeding on probing were also recorded. RESULTS: High marginal bone rates at T24 were strongly associated with elevated rates between T0 and T6. The levels of metalloproteinase-8 were significantly more elevated around implants with marginal bone loss, in relation to implants without marginal bone loss. Marginal bone loss (MBL) rates at 24 months were associated with initial bone loss rates and initial levels of metalloproteinase-8. CONCLUSIONS: Peri-implant marginal bone loss progression is statistically correlated to peri-implant sulcular fluid levels of metalloproteinase-8. Moreover, the initial high levels of marginal bone loss and metalloproteinase-8 can be considered as indicators of the subsequent progression of peri-implant MBL: implants with increased marginal bone loss rates and metalloproteinase-8 levels at 6 months after loading are likely to achieve additional marginal bone loss values.

A Systematic Review of Cementation Techniques to Minimize Cement Excess in Cement-Retained Implant Restorations.

BACKGROUND: The most used types of retention of implant-supported prostheses are screw-retained or cement-retained restorations. The advantages and disadvantages of both have been identified by various authors over the years. However, cement-retained implant crowns and fixed partial dentures are among the most used types of restorations in implant prostheses, due to their aesthetic and clinical advantages. When cemented prostheses are made on implants, the problem of cement residues is important and often associated with biological implant pathologies. The objective of this research was to establish to what extent the techniques to reduce excess cement really affect the volume of cement residues. MATERIALS AND METHODS: This review was written following the PRISMA statement; a detailed search was carried out in three different electronic databases-PubMed, Scopus, and Cochrane Library. The inclusion criteria were prospective clinical studies, with at least 10 participants per group, and with at least 6 months of the follow-up period. RESULTS: There have been many proposals for techniques supposed to reduce the amount of excess cement in the peri-implant sulcus and on the prosthetic components, but of these, which are exceptional in their in vitro capabilities, very few have been clinically validated, and this represents the real limitation and a great lack of knowledge regarding this topic. Three articles met the inclusion criteria, which were analyzed and compared, to obtain the information necessary for the purposes of the systematic review. DISCUSSION: Extraoral cementation can reduce the excess cement, which, after a normal excess removal procedure, is, nevertheless, of such size that it does not affect the possibility of peri-implant pathologies developing. All these studies concluded that a small amount of cement residue is found in the gingival sulcus, and using eugenol-free oxide cements, the residues were only deposited on the metal surfaces, with a better peri-implant tissues health. CONCLUSION: Despite the limitations of this study, it was possible to carefully analyze these characteristics and obtain valuable suggestions for daily clinical practice. Resinous cements are considered, due to the free monomers present in them, toxic for the soft tissues. The provisional zinc-oxide cements, also eugenol-free, represent the ideal choice. The different grades of retentive forces provided by these cements do not seem to have clinical effects on the decementation of restorations.

Sulcus fluid volume, IL-6, and Il-1b concentrations in periodontal and peri-implant tissues comparing machined and laser-microtextured collar/abutment surfaces during 12 weeks of healing: A split-mouth RCT.

OBJECTIVES: To compare gingival tissue healing at surgically manipulated periodontal sites and at sites receiving implants and healing abutments with machined (MS) vs laser-microtextured (LMS) surface placed with one-stage protocol. MATERIAL AND METHODS: Twenty-four non-smoking patients each received two implants with one-stage protocol in a split-mouth design on the same jaw. In each patient, one implant with a MS collar and one immediate healing abutment with a MS, and one implant with a LMS collar and one immediate healing abutment with a LMS were used. Soft tissues healing at surgically manipulated periodontal tissues (T+) and at non-surgically manipulated periodontal tissues (T-) at MS implant sites and at LMS implant sites were compared by means of clinical and biochemical parameters at baseline and at 1-2-3-4-6-8 and 12 weeks. RESULTS: PD and BoP mean values were statistically higher in MS than LMS implant sites (p<0.05). During early healing phase (1-4 weeks), MS and LMS peri-implant tissues and periodontal tissues at T(+) showed no statistically significant difference in crevicular fluid volume changes (p>0.05). Between 6 and 12 weeks, compared with T(+), no statistically significant difference in crevicular fluid volume and IL-6 and IL-1ß concentrations was noted in LMS implant sites (p>0.05), while statistically significantly higher mean values were noted in MS implant sites (p<0.05). CONCLUSIONS: Compared with T(+) and T(-), both MS and LMS implant sites presented a higher pro-inflammatory state in the early phase after surgery (1-4 weeks). At 12 weeks, only MS implant sites kept a higher pro-inflammatory state, while at LMS implant sites, it becomes similar to T(+) and T(-).

Long-Term (> 15 Years) Postrestorative Outcomes of Surgical Crown Lengthening Associated with Early Postsurgical Physiologically Oriented Crevicular Repreparation (POCR) Technique in Esthetic Areas.

Surgical crown lengthening (SCL) is indicated to reestablish the biologic width and to increase the extent of supragingival tooth structure for restorative or esthetic purposes. The present study aimed to evaluate the postrestorative conditions and positional changes of the periodontal tissues following SCL 15 years or more after surgery. Moreover, an early postsurgical physiologically oriented crevicular tooth repreparation (POCR) approach for surgical and restorative phases of the SCL procedure is described. Eighteen patients who needed SCL to gain retention necessary for prosthetic treatment, or previous prosthetic margins, were included. During surgery, the bone level was reduced based on the future prosthetic margin and predetermined biologic width; flaps were placed at the bony crest. Relined temporary acrylic resin crowns were delivered 7 to 10 days postsurgery, and definitive crowns were delivered 9 months postsurgery. Patients were examined at baseline (BSL); at 3, 6, and 9 months postoperatively; and at each yearly recall visit. The following parameters were evaluated: Plaque and Gingival Indices, free gingival margin, width and thickness of the keratinized gingiva, probing depth, attachment level, bone level, direct bone level, and biologic width. Sixteen patients completed the study. No significant change in the position of the free gingival margin and periodontal parameters were seen from 9 months to > 15 years. Biologic width at 9 months was smaller compared to BSL (-0.06 ± 0.02 mm) and gradually increased during the follow-up period, almost reaching the initial levels at the examinations > 15 years later. The described SCL technique obtained a consistent 3-mm gain of coronal tooth structure and was successful in maintaining stable periodontal tissue conditions, reestablishing the biologic width to its original vertical dimension after 15 years.

Nuclear Magnetic Resonance Microimaging for the Qualitative Assessment of Root Canal Treatment: An Ex Vivo Preliminary Study.

AIM: To assess the potential ability of nuclear magnetic resonance micro-imaging (mMRI) to visualize and identify soft tissue debris and unfilled spaces inside radicular canals in endodontic treated extracted teeth, for understanding the causes of treatment failure. Toward this goal, multi-parametric mMRI and cone beam computed tomography (CBCT) were compared. METHODOLOGY: A non-recoverable root treated human tooth was extracted due to endodontic failure and excessive mobility. It was examined with both CBCT and mMRI: CBCT was performed with 0.125 mm voxel size (GXCB-500, Kavo-Gendex, Brea, CA, USA) and mMRI was performed with a spectrometer operating at 9.4T magnetic field (Bruker Avance-400, Bruker, Billerica, MA, USA). The mMRI images were obtained with a microimaging probe. Relaxation times (T1 and T2) and diffusion-weighted acquisition sequences were used to obtain multi-parametric maps of the extracted tooth (slice thickness of 200 µm and in plane resolution of 30 × 30 µm2). RESULTS: T1 and T2 maps identified unfilled spaces around and close to Gutta-percha cones instead of CBCT images that were not able to highlight this aspect. T1, T2 and apparent diffusion coefficient (ADC) assumed different values in dentine and in voids, characterized by different dimensions. Moreover, they were able to discriminate between infiltrations of water only and deposits of biological material. Because Gutta-percha cones are constituted of hard, non-porous material, they do not provide a signal and in mMRI images appear as zones of noise. CONCLUSIONS: Unlike the CBCT exam, mMRI can detect soft tissue debris and unfilled spaces inside radicular canals. Therefore, this in vitro study showed the potential of mMRI to evaluate the quality of the root canal treatment, suggesting its potential benefit in determining the causes of endodontic failure, without the use of ionizing radiation.

Laser microgrooved vs. machined healing abutment disconnection/reconnection: a comparative clinical, radiographical and biochemical study with split-mouth design.

BACKGROUND: Repeated removal and replacement of healing abutments result in frequent injuries to the soft tissues. PURPOSE: The purpose of this study was to evaluate the effect of disconnection/reconnection of laser microgrooved vs. machined healing and prosthetic abutments on clinical periodontal parameters, marginal bone levels, and proinflammatory cytokine levels around dental implants. MATERIAL AND METHODS: Twenty-four patients each received 2 implants with one-stage protocol in a split-mouth design on the same jaw. In each patient, one healing and prosthetic abutments with a laser microgrooved surface (LMS group) and one healing and prosthetic abutments with machined surface (MS group) were used. Four months following implant placement (T0), the healing abutments were disconnnected and reconnected three times to carry out the impression procedures and metal framework try-in. Four weeks later (T1), definitive prosthetic abutments were installated with screw-retained crowns. Modified plaque index (mPI), modified gingival index (mGI) bleeding on probing (BOP), and probing depth (PD) were recorded at T0 and T1. At the same time points, samples for immunological analyses were taken from the sulcus around each implant. Peri-implant crevicular fluid (PICF) samples were analyzed for interleukin-1beta (IL-1ß), interleukin-6 (IL-6), and tumor necrosis factor (TNF)-α levels using the ELISA kit. RESULTS: At T0 and T1, mPI and mGI showed no statistical difference between the two groups, while higher PD and BoP values were noted for the MS group (P < 0.05). The mean PICF volume and mean concentrations of IL-1ß, IL-6, and (TNF)-α in the LMS group were statistically less than those in the MS group (P < 0.05). In addition, comparison of IL-6 and IL-1ß mean concentrations at T0 and T1 in the MS group showed a statistically significant increase (p < 0.05) over time, which was not noted for the LMS. CONCLUSION: Disconnection/reconnection of healing and prosthetic abutments with a laser-microgrooved surface resulted in less inflammatory molecular response compared with conventional machined ones. TRIAL REGISTRATION: ClinicalTrials.gov NCT04415801 , registered 03/06/2020.

Longevity of Teeth and Dental Implants in Patients Treated for Chronic Periodontitis Following Periodontal Maintenance Therapy in a Private Specialist Practice: A Retrospective Study with a 10-Year Follow-up.

The aim of the present study was to retrospectively evaluate the longevity of teeth and implants during a long-term period in a cohort of periodontally compromised patients, treated and maintained in a private specialist periodontal practice, and to analyze the associated risk factors. Fifty-eight patients (30 men, 28 women) who had received active periodontal therapy (APT) and regular periodontal maintenance (PM) ≥ 10 years were included and evaluated. The following were evaluated: (1) statistically significant differences of clinical parameters assessed at six tooth or implant sites (plaque scores, bleeding score, periodontal probing depth, bleeding on probing, and gingival recession) and radiographic parameters (mesial and distal bone crest loss) between patients with and without tooth/implant loss during PM; and (2) associations between the number of teeth and implants lost and potential risk factors. During PM, the overall average tooth loss was 0.07 teeth/patient/year (0.04 teeth/patient/year for periodontal reasons), while the overall average implant loss was 0.4 implants/patient/year. The overall implant failure was 10.08%, and the rate of implant failure due to biologic reasons was 9.8%. Incidence of implant failures in patients with vs without recurrent periodontal disease was 83.3% vs 16.7% (P < .05). Results showed that in chronic periodontitis patients, ATP followed by long-term PM is successful in keeping the majority of periodontally compromised teeth. In the same patients, a higher tendency for implant loss than tooth loss was found.

Evaluation of peri-implant tissues condition after 10-15 years of loading in treated chronic periodontitis patients attending a private practice setting: A retrospective study.

OBJECTIVES: To retrospectively evaluate the conditions of the peri-implant tissues in treated patients with chronic periodontitis (CP) and in patients without chronic periodontitis (noCP). MATERIALS AND METHODS: A chart review was used to evaluate 267 implants, 134 placed in 42 CP treated patients and 133 placed in 46 noCP patients. The primary outcome was to evaluate the condition of the peri-implant tissues (health, peri-mucositis, and peri-implantitis). The secondary outcome was to evaluate the possible association of some variables, such as, Plaque Index (PI), Bleeding Index (BI), probing pocket depth (PD), bleeding on probing (BoP), bone level (BL), loading time, type of implant placement and loading protocol, type of prosthesis, type of bone, implant manufacturer, and implant diameter and length, with the implant health condition. RESULTS: The analysis of patient files revealed that after 10-15 years of loading (mean loading time 13.4 ± 2.07 years), six noCP patients (13%) experienced implant loss with a total of nine implants (6.7%) lost. The remaining 124 implants were classified: 54 (43.5%) as healthy, 45 (36.3%) with peri-implant mucositis, and 25 (20.2%) with peri-implantitis. Twelve CP subjects (28.5%) experienced implant loss with a total of 19 implants (14.1%) lost. The remaining 115 implants were classified: 34 (29.5%) as healthy, 40 (34.7%) with peri-implant mucositis and 41 (35.6%) with peri-implantitis. Compared with noCP subjects, only treated CP subjects with recurrent periodontal disease (RPD) showed differences statistically significant (p < .05). CONCLUSIONS: After 10-15 years of loading, in CP patients treated in a private practice setting, most implants (70.1%) were classified with some type of peri-implant inflammation. In patients with RPD, a higher tendency for implant loss and peri-implant biologic complications was found.

Comparative Results of Single Implants With and Without Laser-Microgrooved Collar Placed and Loaded with Different Protocols: A Long-Term (7 to 10 years) Retrospective Multicenter Study.

PURPOSE: This nonrandomized, retrospective multicenter study aimed to evaluate success rates, peri-implant marginal bone loss, and clinical parameters around single implants with and without laser-microgrooved collars placed and loaded using different protocols after 7 to 10 years of function. MATERIALS AND METHODS: A chart review was used to select patients treated at five private dental clinics with single dental implants with and without laser-microgrooved collars. Cumulative success rates, peri-implant marginal bone loss, probing depth, Plaque Index, bleeding on probing, and gingival recession were recorded at baseline examinations (ie, definitive restoration delivery) and at each year during the follow-up period. RESULTS: Three hundred single implants (140 without laser-microgrooved collars and 160 with 1.7-mm laser-microgrooved collars) in 300 patients were selected. At the completion of the study period, 26 patients and 26 implants (17 with and 9 without a laser-microgrooved collar) were classified as "dropouts." Implants and restorations were categorized into two subgroups each for a total of four study groups: group 1, immediate implant placement; group 2, delayed implant placement; group 3, immediate nonocclusal loading of prostheses; and group 4, delayed loading of prostheses. Nineteen implants (6.9%) failed clinically (4 [2.7%] with and 15 [11.4%] without a laser-microgrooved collar). The difference in cumulative success rates was statistically significant (P < .05). Radiographically, at the end of the follow-up period, the laser-microgrooved group showed a mean peri-implant marginal bone loss of 0.64 mm compared with 1.82 mm for the non-laser-microgrooved group. At the same time point, a mean probing depth of 0.76 mm was observed for the laser-microgrooved group compared with 2.75 mm for the non-laser-microgrooved group. A statistically significant difference in peri-implant marginal bone loss and probing depth between the two types of implant collars was evident (P < .05). No statistically significant correlation was noted between the types of implant placement/prosthetic restoration and clinical parameters. CONCLUSION: Implants with a laser-microgrooved collar appear to influence the peri-implant soft and hard tissue stability, reducing the probing depth levels and the peri-implant marginal bone loss by more than 50% after 10 years of function, regardless of the type of implant placement and loading protocol.

Immediate non-submerged implants with laser-microtextured collar placed in the inter-radicular septum of mandibular molar extraction sockets associated to GBR: Results at 3-year.

BACKGROUND: The aim of the present study was to radiographically evaluate the vertical socket walls changes, and the peri-implant marginal bone remodelling, and clinicallly the soft tissues conditions around the non-submerged single implants placed into the inter radicular septum of mandibular molar sockets, associated with a collagen membrane, after 3 years of loading. MATERIAL AND METHODS: Thirty patients underwent to placement of a non-submerged implants with a laser-microtextured collar into the inter radicular septum of mandibular molar fresh extraction sockets. A collagen membrane and the mucoperiosteal flap were adapted around the neck of the implants, leaving the laser-microtextured collar to heal in a transmucosal fashion. RESULTS: At the end of the follow-up period, no statistical differences were found for each radiographic measurements used for the examination of extraction sockets vertical bone changes. Compared to implants placement, at the end of the 3-year follow-up, the vertical radiographic mesial and distal peri-implant marginal bone levels showed a statistically significant gain of 0.9 (SD 0.5), and 1.0 mm (SD 0.6), respectively (P=0.037). CONCLUSIONS: In mandibular fresh extraction sockets, the method of GBR around transmucosal implants with laser-microtextured surface placed into the interadicular septum may be used successfully to counteract the ridge remodelling. Key words:Non-submerged implants, GBR, laser-microtextured collar.

Features of peri-implantitis associated with luting cement extrusion: a histopathologic report in humans.

OBJECTIVE: To describe and illustrate the histologic characteristics of luting cement-induced peri-implantitis in the posterior maxilla of a 56-year-old man. CASE PRESENTATION: A dental implant inserted 6 years previously in the maxillary left first premolar region revealed pus and swelling. A periapical radiograph showed severe bone loss around the dental implant, and the presence of surrounding residual particles of luting cement. The implant was removed with its adjacent tissues. The harvested implant was fixed in formaldehyde solution (formalin). A 4-mm fragment of soft tissue and a 6-mm fragment of bone were cut from the implant specimen and submitted for routine processing of hematoxylin-eosin (h&e) slides for histologic analysis. The implant specimen was processed and embedded in glycol methacrylate resin and ground to a thickness of 50 µm for histologic examination. RESULTS: The microscopic examination of the h&e slides showed connective tissue with an inflammatory infiltrate composed of histiocytes, lymphocytes, and plasma cells. There was a fragment of viable bone integrated with the bone graft material. The bone showed evidence of active resorption by osteoclasts in Howship lacunae. The implant sections showed trabecular bone with lamellar structure in the apical portion. Foreign body, compatible with luting cement, was present in the coronal portion, adjacent to the threads of the implant, as well as osteoclasts in Howship lacunae. CONCLUSION: This report, documenting a case of peri-implantitis associated with excess cement extrusion, revealed that that the bone loss was associated with an inflammatory infiltrate. Additional studies focusing on the histopathologic characteristics of peri-implantitis could help to increase the knowledge of peri-implant disease to shed light on prevention and treatment.

Implants with a Laser-microgrooved Collar Placed in Grafted Posterior Maxillary Extraction Sockets and in Crestally Grafted Sinuses: a 5-Year Multicentre Retrospective Study.

OBJECTIVES: The aim of this retrospective multicentre cohort study was to compare clinical outcomes, soft tissues conditions and differences in marginal bone loss between implants with a laser-microgrooved collar placed in posterior maxillary extraction sockets grafted by 4 to 5 months, and in posterior maxillary pristine bone (spontaneously healed posterior maxillary extraction sockets) by means of osteotome-mediated sinus floor elevation, over a period of 5 years after functional loading. MATERIAL AND METHODS: Patients of Group 1 underwent extractions with sockets preservation using porcine-derived bone, covered with collagen membrane. Group 2 underwent extractions without socket preservation. Patients of Group 1 received implants in grafted sites, and Group 2 received implants in spontaneously healed bone using a maxillary sinus lift with crestal approach. RESULTS: Over the observation period, the overall clinical success rate in Group 1 and Group 2 was 98% and 100%, respectively, with no differences between the procedures and implants used. Cumulative radiographic marginal bone loss ranged from 0.03 to 0.39 mm after 60 months of functional loading. There were no statistically significant differences in marginal bone loss between short and standard-length implants placed in grafted extraction sockets and in pristine bone. CONCLUSIONS: Short and standard implants with a laser-microgrooved collar, placed in posterior maxillary extraction sockets grafted by 4 to 5 months, and in posterior maxillary pristine bone (spontaneously healed posterior maxillary extraction sockets) by means of osteotome-mediated sinus floor elevation, exhibited no statistical difference in success rate, clinical parameters and marginal bone loss.

A Retrospective Multicenter Study on Short Implants With a Laser-Microgrooved Collar (≤7.5 mm) in Posterior Edentulous Areas: Radiographic and Clinical Results up to 3 to 5 Years.

PURPOSE: We aimed to retrospectively evaluate the radiographic and clinical results and the success rate of short implants with a laser-microgrooved collar (≤7.5 mm) placed in the posterior areas after up to 3 to 5 years of function and the possible influence of several variables-such as gender, periodontitis, smoking habit, location, implant stability at placement, and prosthetic fixation design-on implant marginal bone loss (MBL). MATERIALS AND METHODS: A chart review was used for this multicenter study, which involved 5 private dental clinics. All patients had been treated with short dental implants with a laser-microgrooved collar from January 2012 to December 2015. RESULTS: A total of 174 patients (99 male and 75 female patients; mean age, 51.6 ± 2.8 years) with 254 implants were evaluated. Seven short implants failed. The cumulative success rate was 97.2%, without a statistically significant difference between implants placed in the posterior maxilla and mandible. The mean MBL was 0.18 ± 0.7 mm at the mesial aspect and 0.19 ± 0.6 mm at the distal aspect. No statistical relationships were found between MBL and gender, periodontitis, smoking habit, location, implant stability at placement, and prosthetic fixation design. CONCLUSIONS: At the end of the 3- to 5-year follow-up period, short implants with a laser-microgrooved collar (≤7.5 mm) in the posterior areas yielded a relatively high cumulative success rate. The laser-microgrooved collar implant maintained stable marginal bone levels. No investigated variable was statistically associated with MBL.