Patient-, implant- and prosthetic-related factors on peri-implant mucositis and bone loss.

Peri-implant diseases, including peri-implant mucositis (PIM) and peri-implantitis, are a chronic inflammatory disorder triggered by bacterial biofilm in susceptible hosts. Potential risk factors for peri-implant diseases include smoking, dental plaque accumulation, poor oral hygiene, genetics, and absence of peri-implant keratinized mucosa. This cohort study aimed to evaluate the influence of patient-, implant-, and prosthetic-related factors on PIM and peri-implant bone loss (PBL) around dental implants after 1 year of loading. A total of 54 subjects (22 males and 32 females) were included in the study. Peri-implant clinical parameters were assessed and standardized periapical radiographs of each dental implant were obtained 15 days after the definitive prosthesis installation (baseline) and at 3, 6, and 12 months of follow-up. A total of 173 implants were evaluated. PIM affected 44.8% of the implants and no significant association was found between the investigated parameters and PIM incidence, except for type of implant connection. A significantly higher incidence of PIM (80.0%) was observed for implants with internal hexagon connection type after 1 year of follow-up (p = 0.015). Moreover, a mean PBL of 0.35 ± 1.89 mm was observed and no dental implant was affected by peri-implantitis after 1 year of function. No specific influence of patient, implant, or prosthetic factors on PBL was observed. No association was found between the occurrence of PIM/PBL and the patient-, implant-, and prosthetic-related factors investigated in this cohort study, except for the type of dental-implant connection.

Ultrastructural and immunohistochemical evaluation of hyperplastic soft tissues surrounding dental implants in fibular jaws.

In reconstructive surgery, complications post-fibula free flap (FFF) reconstruction, notably peri-implant hyperplasia, are significant yet understudied. This study analyzed peri-implant hyperplastic tissue surrounding FFF, alongside peri-implantitis and foreign body granulation (FBG) tissues from patients treated at the Department of Oral and Maxillofacial Surgery, Seoul National University Dental Hospital. Using light microscopy, pseudoepitheliomatous hyperplasia, anucleate and pyknotic prickle cells, and excessive collagen deposition were observed in FFF hyperplastic tissue. Ultrastructural analyses revealed abnormal structures, including hemidesmosome dilation, bacterial invasion, and endoplasmic reticulum (ER) swelling. In immunohistochemical analysis, unfolded protein-response markers ATF6, PERK, XBP1, inflammatory marker NFκB, necroptosis marker MLKL, apoptosis marker GADD153, autophagy marker LC3, epithelial-mesenchymal transition, and angiogenesis markers were expressed variably in hyperplastic tissue surrounding FFF implants, peri-implantitis, and FBG tissues. NFκB expression was higher in peri-implantitis and FBG tissues compared to hyperplastic tissue surrounding FFF implants. PERK expression exceeded XBP1 significantly in FFF hyperplastic tissue, while expression levels of PERK, XBP1, and ATF6 were not significantly different in peri-implantitis and FBG tissues. These findings provide valuable insights into the interconnected roles of ER stress, necroptosis, apoptosis, and angiogenesis in the pathogenesis of oral pathologies, offering a foundation for innovative strategies in dental implant rehabilitation management and prevention.

Peri-implant Tissue Health and Bone Resorption in Implant- Supported Fixed Partial Rehabilitations.

PURPOSE: To evaluate peri-implant tissue health and bone resorption in patients with implant-supported fixed partial rehabilitations. In particular, possible correlations between plaque accumulation and bone loss, as well as other periimplant health parameters, were investigated. MATERIALS AND METHODS: A total of 44 patients rehabilitated with fixed implant-supported partial rehabilitations were included. The following parameters were recorded: spontaneous bleeding (SB), suppuration, bleeding on probing (BOP), plaque index (PI), and probing depth (PD). Periapical radiographs were taken to measure crestal bone loss (BL). A nonparametric test (Spearman rank coefficient; rs) was used to identify possible correlations between the clinical parameters recorded. RESULTS: A total of 121 implants were analyzed. Global PI and BOP were 49.58% and 20.25%, respectively. There were no cases of suppuration, and only 2 implants showed spontaneous bleeding. Mean BL was 1.53 mm (SD: 0.98). No implants showed peri-implantitis. There was a weak, statistically significant correlation between PI and BL (rs = 0.27, P [2-tailed] = .99) and between PI and the other peri-implant parameters (BOP: rs = 0.14, P = .14; PD: rs = 0.04, P = .65; SB: rs = -0.08, P = .34). A very weak correlation was also found between BL and BOP (rs = 0.1, P = .2) and between BL and PD (rs = 0.02, P = .7). Correlation was found between BL and age (rs = 0.13, P = .81) and between the other peri-implant parameters and age using dichotomization (> or < 65 years; PI: rs = -0.14, P = .11; PD: rs = -0.21, P = .01; BOP: rs = -0.21, P = .01; SB: rs = 0.05, P = .53). No statistically significant correlations were found between the clinical parameters evaluated and the sex or the dental arch treated (maxilla vs mandible). In contrast, the correlation between periodontal parameters and years elapsed since surgery (follow-up) was significant. CONCLUSIONS: The present research suggests that in implant-supported fixed partial rehabilitations, dental implants with greater plaque accumulation are more likely to present augmented probing depth, peri-implant inflammation, and bone loss, although the correlation is statistically very weak. Patient age and time of follow-up also significantly affected peri-implant health parameters.

Peri-implantitis in patients without regular supportive therapy: Prevalence and risk indicators.

OBJECTIVES: To determine the prevalence of peri-implant diseases in patients treated in a university setting without a regular peri-implant supportive therapy schedule, and to identify the risk indicators associated with peri-implantitis. MATERIAL AND METHODS: A retrospective cohort study was made of patients with dental implants with at least 12 months of functional loading who did not receive regular peri-implant supportive therapy. Patient- and implant-related variables were retrieved, and clinical and radiological examinations were performed. Descriptive and bivariate analyses and multilevel logistic regression analyses were performed to identify factors associated with peri-implantitis. RESULTS: A total of 213 implants in 88 patients were analyzed. The patient-level prevalence of peri-implantitis and peri-implant mucositis was 26.1% (95%CI: 16.7%-35.5%) and 44.3% (95%CI: 34.0%-54.6%), respectively. Peri-implant diseases were significantly more frequent when the width of the keratinized mucosa was < 2 mm (OR = 5.26; 95%CI: 1.24-22.26; p = 0.024), and when there was 12 month post-loading bone loss (OR = 2.96; 95%CI: 1.35-6.52; p = 0.007). CONCLUSIONS: Peri-implantitis is a common finding in patients without regular peri-implant supportive therapy (prevalence 16.7-35.5%). A thin peri-implant keratinized mucosa (< 2 mm) and a higher degree of bone remodeling after loading seem to be the main risk factors for peri-implantitis in this patient profile. CLINICAL RELEVANCE: Patients who do not engage in supportive peri-implant maintenance have a higher risk of peri-implantitis. A thin keratinized mucosa and bone loss during the first year of loading are predisposing factors for peri-implantitis.

Comparative Assessment of Catalase Levels in Peri-Implant Health and Disease.

Peri-implant disease pathogenesis is similar to periodontal disease pathogenesis resulting in production of pro-inflammatory mediators. These mediators alter the redox balance leading to decrease in antioxidants, among which catalase is one of the enzymatic antioxidants. The aim of the study was to compare the levels of catalase in peri-implant health and disease. The present observational study was carried out from June 2022 to December 2022 in the Department of Implantology, Saveetha Dental College and Hospitals, Chennai, India. A total of 60 patients with peri-implant health (Group 1; n = 20), peri-implant mucositis (Group 2; n = 20) and peri-implantitis (Group 3; n = 20) were enrolled. Unstimulated salivary samples were collected and subjected to ELISA for catalase analysis. Catalase levels were then compared between the groups using ANOVA. The mean catalase level in peri-implant health, peri-implant mucositis, peri-implanti-tis were 25.07 ± 0.44 U/mL, 18.5 6 ± 0.65 U/mL, and 11.25 ± 0.76 U/mL respectively. The difference between the three groups were statistically significant (P < 0.05). Catalase level decreases with severity of peri-implant diseases. Therefore, catalase can be used as a diagnostic marker for peri-implant diseases.

Comparative Evaluation of C-Reactive Protein Levels among Peri-Implant Health and Disease Conditions.

Peri-implant disease pathogenesis results in production of pro-inflammatory mediators, among which C-reactive protein (CRP) is one of the acute phase reactants. The aim of the study was to comparative CRP levels among peri-implant health and disease conditions. The present study was carried out in the Department of Implantology, Saveetha Dental College and Hospitals, Chennai, India. A total of 40 patients with peri-implant health (n = 10), peri-mucositis (n = 10), early peri-implantitis (n = 10) and advanced peri-implantitis (n = 10) were enrolled. Unstimulated salivary samples were collected and subjected to latex agglutination assay for CRP analysis. CRP levels were then correlated with peri-implant health and diseases. CRP level in peri-implant health, peri-implant mucositis, early peri-implantitis and advanced peri-implantitis were 0.18 ± 0.04 mg/dL, 2.05 ± 0.61 mg/dL, 4.14 ± 1.82 mg/dL and 6.21 ± 1.35 mg/dL respectively. There was a statistically significant difference in CRP levels between all the tested groups (ANOVA, P = 0.03). Pearson correlation coefficient analysis revealed a strong positive correlation between CRP and peri-implant health status. CRP level was high among patients with peri-implantitis followed by peri-implant mucositis and peri-implant health. Also, CRP level increases with severity of peri-implant diseases and there exists a positive correlation between CRP level and peri-implant health status.

The Impact of Implant Abutment Angle and Height on Peri-implant Tissue Health: Retrospective Analyses from a Randomized Controlled Clinical Trial.

PURPOSE: To examine the influence of abutment emergence angle and abutment height on marginal peri-implant bone stability in patients not considered susceptible to peri-implantitis. Furthermore, it was analyzed whether titanium-base (Ti-base) abutments lead to wider abutment emergence angles compared to one-piece abutments. MATERIALS AND METHODS: A total of 48 abutments (ie, 24 Ti-base and 24 one-piece abutments in 24 patients) were evaluated at abutment installation, after 1 year, and thereafter on a yearly basis for up to 5 years. Clinical and radiographic outcome variables were assessed. RESULTS: With regard to peri-implant marginal bone stability, only moderately negative, albeit significant, correlations were found on the mesial sides of the one-piece abutments after 4 and 5 years for an abutment emergence angle > 30 degrees. No statistically significant negative correlations were found for distances of ≤ 1.5 mm between the restoration margin and the crestal peri-implant bone level for either Ti-base or for one-piece abutments. Furthermore, abutments bonded to Ti-bases were not associated with larger emergence angles than one-piece abutments. CONCLUSIONS: For patients at low risk of developing peri-implantitis, it can be concluded that neither a larger abutment emergence angle (> 30 degrees) nor a distance of ≤ 1.5 mm between the restoration margin and the crestal peri-implant bone level are associated with marginal peri-implant bone loss. Furthermore, abutments bonded to Ti-bases are not associated with wider emergence angles than one-piece abutments.

The impact of electronic cigarettes on peri-implant health: A systematic review and meta-analysis.

OBJECTIVES: Recent literature suggests that the use of electronic cigarette (e-cigarette) is a substantial contributing factor to the unsuccessful outcomes of dental implant procedures. Our aim was to systematically review the effect of e-cigarette use on clinical (PI, PD, BOP), radiographic (bone loss), and immunologic (IL-1ß) peri­implant parameters. DATA: Main search terms used in combination: electronic cigarette, peri­implantitis, vaping. SOURCES: An electronic search was undertaken for MEDLINE, EMBASE, COCHRANE, and SCOPUS databases between 2017 and 2023. STUDY SELECTION: The study protocol was developed according to PRISMA guidelines, and the focus question was formulated according to the PICO strategy. No restriction was accepted regarding language or year to avoid selection bias; the initial database search yielded 49 publications. Following the selection process, only seven studies met the inclusion criteria. Seven studies were statistically analyzed via MedCalc program. A pooled effect was deemed statistically significant if the p-value was less than 0.05. CONCLUSION: Electronic cigarettes cause an increase in probing depth, bone loss, and the level of IL-1ß, one of the bone destruction mediators in the tissues around the implant, and a decrease in bleeding on probing. CLINICAL SIGNIFICANCE: E-cigarette is a potential risk factor for the healing process and the results of implant treatment, similar to cigarettes. Performing clinical research to evaluate the e-cigarette effect on peri­implantitis in an age and gender-match population is needed.

Rat Peri-implantitis Models: A Systematic Review and Meta-analysis.

PURPOSE: To review experimental peri-implantitis studies using rat models and summarize different peri-implantitis induction techniques and evaluate their effectiveness. MATERIALS AND METHODS: Electronic searches were conducted by two independent examiners to address the following issues. Meta-analyses explored the marginal bone loss (MBL) of four types of peri-implantitis induction methods in rats. The detailed induction tactics-such as the implant design, implant size, surgical process, time cost, induction methods, and endpoint measurements-were summarized. RESULTS: Of the 18 included studies, 38.9% of the studies placed implants at the maxillary first molar, and 44.4% placed them at the alveolar ridge region anterior to the maxillary first molar. As for the induction method, the numbers of published studies on ligature methods, bacterial inoculation, and bacterial lipopolysaccharide inoculation were equally high among all selected studies. The total implant survival rate at the end was 160 out of 213 implants (75.11%). Eight studies with high pooled heterogeneity (I2 = 98, P < .01) in the meta-analysis reported an overall MBL (µ-CT) of 0.47 mm (95% CI = 0.14 to 0.81). A subgroup analysis estimated an MBL of 0.31 mm (95% CI = 0.12 to 0.50) for bacterial inoculation and 0.66 mm (95% CI = 0.07 to 1.26) for the ligature method. Histopathologic analysis revealed that peri-implantitis in rats was similar to peri-implantitis lesions in humans. CONCLUSIONS: Implant placement at the maxillary first molar with bacterial inoculation and the silk ligature method to build peri-implantitis rat models is reliable to use for research on peri-implantitis.

Delayed Implant Fixture Displacement into the Maxillary Sinus Five Years Post-Loading: Unraveling the Causes - A Case Report.

Reports of implant fixtures dislocating into the maxillary sinus during sinus graft procedures are well-documented. However, cases of fixtures migrating into the sinus long after placement have yet to be reported. This case report details the surgical extraction of a displaced screw and cement-retained prosthesis, including a fixture and its abutment, from the maxillary sinus after a minimum of 5 years under functional load. The extracted implant was subsequently examined using scanning electron microscopy and energy-dispersive x-ray spectroscopy. We found that the migration commenced with peri-implantitis surrounding the implant, replacing the second molar. This was accompanied by a loss of cement from the crown on this implant and concurrent loosening of the abutment screw on the implant, replacing the first molar. We hypothesize that the inability of the bony tissue surrounding the second molar implant to withstand occlusal forces resulted in forming a bony sequestrum. This process ultimately precipitated the migration of the fixture, along with its abutment and adjacent necrotic bone, into the sinus cavity.

Correlation of C-Reactive Protein and Severity of Peri-Implant Diseases.

Peri-implant disease pathogenesis is similar to periodontal disease pathogenesis resulting in production of pro-inflammatory mediators. These mediators are released during the inflammation phase, among which C-reactive protein (CRP) is one of the acute phase reactants. The aim of the study was to correlate the levels of CRP with the severity of peri-implant diseases. The present observational study was carried out from June 2022 to December 2022 in the Department of Implantology, Saveetha Dental College and Hospitals, Chennai, India. A total of 60 patients with peri-implant health (n = 20), peri-mucositis (n = 20) and peri-implantitis (n = 20) were enrolled. Unstimulated salivary samples were collected and subjected to latex agglutination assay for CRP analysis. CRP levels were then correlated with severity of peri-implant diseases. The mean CRP level in peri-implant health, peri-implant mucositis, peri-implantitis were 0.25 ± 0.36 mg/dl, 3.56 ± 0.85 mg/dl and 5.07 ± 0.74 mg/dl, respectively. Pearson correlation coefficient analysis revealed a strong positive correlation between CRP and peri-implant parameters suggesting that the CRP level increased as the severity of peri-implant disease increased. CRP level increases with severity of peri-implant diseases and there exists a positive correlation between CRP level and peri-implant parameters. Therefore, CRP can be used as a diagnostic marker for peri-implant diseases.

Peri-implantitis increases the risk of medication-related osteonecrosis of the jaws associated with osseointegrated implants in rats treated with zoledronate.

This study evaluated the peri-implant tissues under normal conditions and under the influence of experimental peri-implantitis (EPI) in osseointegrated implants installed in the maxillae of rats treated with oncologic dosage of zoledronate. Twenty-eight senescent female rats underwent the extraction of the upper incisor and placement of a titanium dental implant (DI). After eight weeks was installated a transmucosal healing screw on DI. After nine weeks, the following groups were formed: VEH, ZOL, VEH-EPI and ZOL-EPI. From the 9th until the 19th, VEH and VEH-EPI groups received vehicle and ZOL and ZOL-EPI groups received zoledronate. At the 14th week, a cotton ligature was installed around the DI in VEH-EPI and ZOL-EPI groups to induce the EPI. At the 19th week, euthanasia was performed, and the maxillae were processed so that at the implanted sites were analyzed: histological aspects and the percentage of total bone tissue (PTBT) and non-vital bone tissue (PNVBT), along with TNFα, IL-1ß, VEGF, OCN and TRAP immunolabeling. ZOL group presented mild persistent peri-implant inflammation, higher PNVBT and TNFα and IL-1ß immunolabeling, but lower for VEGF, OCN and TRAP in comparison with VEH group. ZOL-EPI group exhibited exuberant peri-implant inflammation, higher PNVBT and TNFα and IL-1ß immunolabeling when compared with ZOL and VEH-EPI groups. Zoledronate disrupted peri-implant environment, causing mild persistent inflammation and increasing the quantity of non-vital bone tissue. Besides, associated with the EPI there were an exacerbated inflammation and even greater increase in the quantity of non-vital bone around the DI, which makes this condition a risk factor for medication-related osteonecrosis of the jaws.

Predictive factors for the treatment success of peri-implantitis: a protocol for a prospective cohort study.

INTRODUCTION: Peri-implantitis, a common biological complication of dental implant, has attracted considerable attention due to its increasing prevalence and limited treatment efficacy. Previous studies have reported several risk factors associated with the onset of peri-implantitis (eg, history of periodontitis, poor plaque control and smoking). However, inadequate data are available on the association between these risk factors and successful outcome after peri-implantitis therapy. This prospective cohort study aims to identify the local and systemic predictive factors for the treatment success of peri-implantitis. METHODS AND ANALYSIS: A single-centre cohort study will be conducted by recruiting 275 patients diagnosed with peri-implantitis. Sociodemographic variables, healthy lifestyles and systemic disorders will be obtained using questionnaires. In addition, clinical and radiographic examinations will be conducted at baseline and follow-up visits. Treatment success is defined as no bleeding on probing on more than one point, no suppuration, no further marginal bone loss (≥0.5 mm) and probing pocket depth ≤5 mm at the 12-month follow-up interval. After adjustment for age, sex and socioeconomic status, potential prognostic factors related to treatment success will be identified using multivariable logistic regression models. ETHICS AND DISSEMINATION: This cohort study in its current version (2.0, 15 July 2022) is in accordance with the Declaration of Helsinki and was approved by the Ethics Committee of Stomatological Hospital, Southern Medical University (EC-CT-(2022)34). The publication will be on behalf of the study site. TRIAL REGISTRATION NUMBER: ChiCTR2200066262.

Influence of keratinized mucosa on peri-implant diseases: a retrospective cohort study in humans.

OBJECTIVE: The present study aimed to assess the relationship between keratinized mucosa width and peri-implant diseases, namely peri-implant mucositis and peri-implantitis. MATERIALS AND METHODS: Ninety-one dental implants in function for ≥ 6 months from 40 partially or completely edentulous non-smoker subjects (24 females and 16 males) were evaluated clinically and radiographically. The width of keratinized mucosa, probing depth, plaque index, bleeding on probing, and marginal bone levels were assessed. Keratinized mucosa width was categorized as ≥ 2 mm or < 2 mm. RESULTS: There was no statistically significant association between keratinized buccal mucosa width and peri-implant mucositis or peri-implantitis (p ≥ 0.37). In the regression analysis, peri-implantitis was associated with longer implant function time (RR: 2.55, 95% CI: 1.25-11.81, p = 0.02) and implants in the maxilla (RR: 3.15, 95% CI: 1.61-14.93, p = 0.003). Mucositis was not associated with any of the factors analyzed. CONCLUSION: In conclusion, in the present sample, keratinized buccal mucosa width was not associated with peri-implant diseases, suggesting that a band of keratinized mucosa may not be necessary to maintain peri-implant health. Prospective studies are required to better understand its role in the maintenance of peri-implant health.

The relationship of peri-implant soft tissue wound healing with implant cover screw design: Cross-sectional study.

INTRODUCTION: Dental implants are frequently preferred method for oral rehabilitation all over the world. The incidence of various complications such as incorrect prosthesis, peri-implant mucositis, and peri-implantitis is high; premature loss of implants is encountered due to osteointegration process not being completed for some unexplained reasons. However, there is no study in the literature examining the nonfunctional period of implants. Closure screws of different implant companies have different designs like surface properties, and areas, where closure screws sit, are important reservoirs for microorganism colonization. Our study aims to evaluate the inflammatory response, epithelial maturation, and epithelial-connective tissue interaction around closure screws. METHODS: For this purpose, 52 implants belonging to five different implant companies were included in the study. Tissues removed over the cover screw during fitting of healing caps were used as biopsy material and for epithelial proliferation Ki-67, for epithelium-connective tissue interaction Syndecan-1, and for macrophage activation CD-68 expressions were evaluated by immunohistochemical analysis. Scanning electron microscopy (SEM) analyzes were performed to evaluate the presence of gap between the implant and the cover screw. RESULTS: As a result of our study, intensity of subepithelial inflammation between groups wasn't statistically different. Differences in CD-68 and Syndecan-1 levels were obtained at the lamina propria level. H score of CD-68 was statistically significantly different in epithelium (p = 0.032), and H score of Syndecan-1 was different in lamina propria (p = 0.022). There wasn't a statistically significant difference between the groups for Ki-67 (p = 0.151). CONCLUSION: Our study results indicate that in addition to the implant surface morphology, the design of the closure screws is important in the inflammatory response and epithelial maturation that develops during wound healing. Although the inflammatory response is required for healing, osteointegration, and implant survival, further investigation is needed to investigate the relationship between initial neck resorption and closure screws with radiographic and microbiological examinations.

Knowledge and attitude of dental students regarding etiology, diagnosis, and treatment of peri-implantitis.

OBJECTIVE: The objective of this study was to assess the level of knowledge and attitude of dental students about the etiology, diagnosis, and management of peri-implantitis. METHODS: An online cross-sectional study that targeted senior undergraduate dental students at the College of Dentistry was conducted. A closed-ended survey consisting of 28 questions was designed. Three sections were created: 1) participants' characteristics; 2) Knowledge of peri-implantitis etiology, risk factors, diagnosis, and complications; 3) The use of antibiotics in peri-implantitis, diagnosis, and treatment methods. SPSS version 22 (IBM Corp.) was used for data analysis. Counts and percentages were calculated for correct answers in each section. RESULTS: A total of 267 dental students responded to the questionnaire. The majority of the participants (81.6%) were knowledgeable about peri-implantitis being an inflammatory reaction, and a lesser percentage (77.9%) knew that bacterial plaque is an etiologic factor for peri-implant diseases. 82.0% of the participants identified smoking as a risk factor, followed by periodontitis (80.5%). Regarding implant complications, 57.3% of the participants considered implant mobility as a definitive indication for implant removal. More than half of the participants reported using crater-like bone defects surrounding implants to diagnose peri-implantitis. The most commonly used antibiotic was amoxicillin (34.1%), followed by amoxicillin combined with metronidazole (26.9%). CONCLUSION: Most participants had a basic understanding of the etiology and risk factors of peri-implantitis. On the other hand, more courses addressing peri-implantitis diagnosis are needed.

Dose- and time-dependent association of smoking and its cessation with risk of peri-implant diseases.

DESIGN: A retrospective cohort study involved patients who received at least one implant-supported restoration at a university dental clinic between 2001 and 2013. Patients were randomly selected from an electronic database, and their recruitment via telephone contact spanned from February 2021 until July 2021. MAIN OBJECTIVE: To investigate the association of smoking and its cessation with the risk of peri-implant mucositis and peri-implantitis in a cohort of implant-treated patients. METHODS: The study adhered to the principles outlined in the Declaration of Helsinki and followed the STROBE guidelines for reporting observational research. Included were adult patients who were rehabilitated with dental implants, irrespective of the type of edentulism, superstructure, and prosthetic retention, provided that they had adequate access for peri-implant probing. Patients with incomplete records were excluded. Clinical measurements included plaque and bleeding indices, periodontal pocket depth, suppuration on probing, mucosal recession, and width of keratinized mucosa. Periapical radiographs were taken and marginal bone level (MBL) was measured using ImageJ software. The primary outcome variable was peri-implant status which was classified into: health (H), peri-implant mucositis (PM), and peri-implantitis (PI). Smoking status was categorized into: never-smokers, former smokers, and current smokers. Smoking information included: daily cigarette consumption, duration of smoking (in years), and age at initiation, and for former smokers, the duration of smoking cessation. RESULTS: The cohort included 117 patients (55 females and 62 males) with a mean age of 64.2 years at examination. They were rehabilitated by 450 implants, with an average of 4.6 implants per patient and a mean duration of 8 years in function. Out of the total, 39 patients were H, while 41 and 37 showed PM and PI, respectively. Periodontal and MBL measures were significantly higher in PM and PI groups compared to H group (p < 0.001). Considering tobacco use, 56 patients were never-smokers, 42 former smokers, and 19 current smokers. The average daily consumption of cigarettes was 15.7. Ever-smokers >23 pack-years had a significantly higher risk for PI (OR = 3.40; 95% CI 0.91-17.30; p = 0.002) compared to nonsmokers. Regression analysis showed that subjects with a span since smoking cessation of more than 21 years exhibited a significantly lower risk of peri-implant diseases (PIDs) than those who had ceased smoking within 21 years (p = 0.028). CONCLUSION: A smoking intensity exceeding 23 pack-years was significantly associated with PI risk, while the risk of PIDs was comparable between never-smokers and those who had quit smoking more than 21 years ago.

Clinical outcomes of implant- versus abutment-level connection in screw-retained fixed dental prostheses: A 5-year randomized controlled trial.

AIM: The aim of the study was to evaluate the 5 years clinical outcomes associated with implant-level connection (IL) versus abutment-level connection (AL) for implants with an internal conical connection (ICC) supporting a screw-retained fixed partial denture. MATERIALS AND METHODS: Fifty patients with 119 implants were randomly allocated to either the AL or IL group. Radiographic (Marginal bone loss) and clinical outcomes (Bleeding on Probing, probing pocket depth, plaque accumulation, incidence of peri-implantitis and peri-implant mucositis as well as prosthetic complications) were collected and compared at 1, 2, 3, and 5 years. A linear mixed model was used to evaluate the differences between groups. RESULTS: Five years after treatment, the MBL change was not significantly different between the groups at any point. The MBL was 0.23 ± 0.64 mm (AL) and 0.23 ± 0.29 mm (IL). The bleeding on Probing was 44% (AL) and 45% (IL) (p = .89). The mean probing depth was 2.91 ± 1.01 mm (AL) and 3.51 ± 0.67 mm (IL). This difference between the groups was statistically significant but clinical insignificant. Presence of plaque was slightly higher (p = .06) in the IL group (34.4%) compared with the AL group (26.3%). The overall technical, biological, and prosthetic complication rates were similar between groups. None of the implants developed peri-implantitis during the entire follow-up period. CONCLUSION: The results of this clinical trial indicated that all clinical and radiographical parameters were clinically comparable between the study groups.

Clinical Performance of Two-Piece Zirconia Dental Implants After 5 and Up to 12 Years.

PURPOSE: To assess the clinical performance of a two-piece zirconia implant system, with a focus on biologic complications. MATERIALS AND METHODS: A total of 39 patients received 91 two-piece zirconia implants. The patients were recruited from two private clinics and were monitored for 5 to 12 years (median: 5.6 years). The primary outcomes were biologic complications, such as peri-implant infections (peri-implant mucositis and peri-implantitis), and the secondary outcome was radiographically evident marginal bone loss (MBL). RESULTS: Three patients (7.7%) with 9 total implants (9.9%) presented with peri-implant mucositis. MBL that did not exceed the first thread was evident at 32 mesial sites (35%) and 25 distal sites (27.4%). MBL exceeding the first thread but not the third thread was evident at 6 mesial and 5 distal sites (thread pitch: 0.7 mm). Only one peri-implant pocket deepened (4 mm) and showed bleeding; however, the estimated MBL did not exceed 1.65 mm. No peri-implantitis occurred, and no implant was lost. CONCLUSIONS: This prospective study shows high survival rates and a seemingly low prevalence of biologic and prosthetic complications for this two-piece zirconia implant system over an observation period of up to 12 years.