Reliability of periodontal diagnostic tools for monitoring peri-implant health and disease

Biomarkers in Peri-Implant Crevicular Fluid of Healthy Implants and Those With Peri-Implant Diseases: A Systematic Review and Meta-Analysis

INTRODUCTION

Several biomarkers in peri-implant crevicular fluid have been studied to diagnose peri-implant diseases with inconclusive results. This systematic review and meta-analysis aimed to comprehensively compare data on the levels of biological components in peri-implant crevicular fluid collected from healthy and diseased implants to identify reliable biomarkers for diagnosing and monitoring peri-implant disease.

MATERIALS AND METHODS

The search strategy included studies comparing biomarker levels in peri-implant crevicular fluid between healthy and diseased implants through electronic databases (MEDLINE/PubMed, Embase, Cochrane Library), grey literature, and hand-searching relevant journals and reference lists of pertinent papers. A two-stage screening was performed in duplicate and independently. In the first stage, titles and abstracts that fulfilled eligibility criteria were screened. In the second stage, a full-text analysis was conducted to verify eligibility. All articles meeting the inclusion criteria underwent data extraction and quality assessment. Meta-analyses were conducted on studies with similar comparisons and outcome measures.

RESULTS

After screening the titles and abstracts, out of 100 potentially relevant papers identified for full-text evaluation, 49 were excluded, 51 were included in the qualitative analysis, and 18 were included in the quantitative synthesis. Among 96 biomarkers assessed, the most studied were pro-inflammatory cytokines (IL-1ß, IL-6, TNF-α, and IL-17), osteoclastogenic-related factors (RANK, RANKL, and OPG), anti-inflammatory cytokines (IL-10), chemokines (IL-8, MIP-1α/CCL3, and MIP-3α/CCL-20), and enzymes (MMP-8, Cat-K, AST, and ALT).

CONCLUSIONS

Meta-analyses comparing data from healthy patients and those with peri-implantitis or mucositis and between patients with mucositis and those with peri-implantitis showed a moderate predictive value of IL-1ß, VEGF, cortisol, and sRANKL/OPG for peri-implantitis.

Periodontal and peri-implant bleeding on probing in patients undergoing supportive maintenance: a cross-sectional study

OBJECTIVE

Assessment of periodontal and peri-implant inflammation, evidenced by bleeding on probing (BOP), among partially dentate patients receiving supportive periodontal care (SPC).

MATERIAL & METHODS

Patient charts from the Center for Dentistry and Oral Medicine of Goethe-University Frankfurt with at least one dental implant were reviewed. Measurements included probing pocket depth (PPD), BOP, and full-mouth bleeding and plaque scores for all teeth and implants.

RESULTS

100 patients (median; lower/upper quartile: age 68.9; 62.6/76.5 years; 51 females, 6 smokers, 16 with anticoagulative medication, 6 localized stage III, 57 generalized stage III, 37 stage IV, 70 grade B, 30 Grade C, 22; 20/25 teeth left, 2; 1/4 implants) were examined. Peri-implant BOP (24; 11.5/41.5%) was significantly higher than BOP at teeth (14; 8/21.5%) (p < 0.001). A median of 0 (0/1) implants exhibited no BOP and 0 (0/1) only one site with BOP. Shallow pockets (PPD 1-3 mm) were significantly more frequent in teeth (93; 87/97%) than in implants (72.5; 58/94.5%; p < 0.001). Moderately deep pockets (PPD 4 and 5 mm) were less frequent in teeth compared to implants (6; 2/11%; 22; 5.5/33%; p < 0.001).

CONCLUSIONS

Peri-implant sites exhibit a higher prevalence of BOP compared to periodontal sites in SPC patients.

CLINICAL RELEVANCE

Practitioners providing supportive periodontal care to patients with dental implants should anticipate a greater prevalence of BOP around implants compared to teeth.

Evaluation of the Peri-Implant Tissues of Patients with Severe Bone Atrophy Treated with a New Short and Extra-Short Implant System-A Pilot Study

This study aimed to assess clinical and radiographic outcomes, including implant survival, marginal bone loss, and patient satisfaction, in individuals with severe bone atrophy treated using a newly developed system of short and extra-short implants. A total of 44 implants (37 short and 7 extra-short) were placed with immediate loading in 11 patients. The patients were followed up at between 6 and 24 months. Bone changes, keratinized mucosa, bleeding on probing, probing depth, crown-to-implant ratio, and patient satisfaction were evaluated. An implant survival and success rate of 100% was observed. The peri-implant bone condition showed no significant associations between marginal bone loss (MBL) and gingival recession. In extra-short implants, the crown-to-implant ratio did not affect MBL in the evaluated times. However, short implants showed a statistically significant inverse correlation between mesial measurement and crown-to-implant ratio (p = 0.006) and between distal measurement and crown-to-implant ratio (p = 0.004) over six months. Plaque was present in the mesiobuccal regions in 38.64% of the implants, with extra-short implants having the highest relative frequency (71.4%). Bleeding was observed in 18.9% of the short implants in the mesiolingual region and 14.3% of the extra-short implants. There was a statistically significant association between bleeding on probing in the mesiobuccal region and the type of implant (p = 0.026). The analysis of probing depth showed no difference between the types of implants. Within the limits of this study, short and extra-short implants presented similar clinical and radiographic behavior of soft and hard tissues in the evaluated times.

Patient's experiences of dental implants, peri-implantitis and its treatment-A qualitative interview study

OBJECTIVES

The aim of the present study was to explore peri-implantitis patients' sensations, expectations, and experiences of dental implants, the disease, as well as undergoing treatment with laser or mucosal flap surgery.

METHODS

Interviews were conducted with 18 patients who had been referred for treatment of peri-implantitis at a specialist clinic. The participants underwent either laser treatment or mucosal flap surgery of affected implants. Qualitative content analysis was used for processing the transcribed interviews with coding in categories and subcategories.

RESULTS

The analysis of the interviews was presented in a narrative way to display the variety of experiences in this patient group. Losing teeth was perceived as frustrating and negatively impacted their quality of life; however, receiving dental implants improved some aspects of the patients' lives. While some have symptoms, others did not seem to notice the incidence and development of peri-implantitis. Local anaesthesia was the worst part of both treatments and both modalities yielded only minor discomforts.

CONCLUSION

There were a variety of positive and negative sensations and experiences perceived by patients with dental implants as a consequence of peri-implantitis, including a negative impact on quality of life. These findings emphasize the importance of thoroughly informing the potential and established dental implant patients of the risk of developing disease and its impact. The treatment of peri-implantitis created in general only slight discomfort for the patient.

Progressive bone loss and bleeding on probing: A cohort study

AIM

To investigate whether a progressive marginal bone loss (PMBL) occurring beyond the initial bone remodeling (IBR) is linked with bleeding on probing.

MATERIALS AND METHODS

A total of 70 partially edentulous patients exhibiting 112 two-piece bone-level implants were included in this retrospective study. Panoramic radiographs were obtained after implant insertion (T0), after delivery of a final prosthetic restoration (T1) and subsequently during the 1-(T2), 5-(T3), 10-(T4), and 15-years (T5) follow-up visits. At each time point, radiographic marginal bone levels were assessed from the implant shoulder to the first bone-to-implant contact at mesial and distal aspects. The IBR was defined as a bone loss occurring up to prosthesis delivery, that is, from T0 to T1. The PMBL was defined as bone loss occurring after T1. At T2, T3, T4, and T5, the presence or absence of bleeding on probing (BOP) was recorded at four sites. A median regression with mixed models was performed to assess the difference of PMBL in PMBL + BOP+ and PBML + BOP- groups.

RESULTS

Over the mean implant functioning time of 4.44 ± 4.91 years, 38 (34%) implants showed no PBML, whereas 74 (66%) implants featured PMBL. Of these, 35 (47%) and 39 (53%) implants were assigned to the PMBL + BOP- and PMBL + BOP+ groups, respectively. The mean PMBL after 1, 5, 10, and 15 years were comparable between implants featuring PMBL with or without BOP. At 1 year, BOP intensity significantly correlated PMBL, with each increase in one BOP-positive site being associated with increase in PMBL by 0.55 mm (p = 0.038), whereas this association was not found at 5, 10, and 15 years. The IBR values in the no PBML, PMBL + BOP+, and PBML + BOP- groups were -0.24 ± 0.31, -0.41 ± 0.59, and -0.24 ± 0.33 mm, respectively, with no significant differences found among the groups.

CONCLUSION

Progressive bone loss at implant sites is not always linked with bleeding on probing.

Influencing Factors Regarding the Severity of Peri-Implantitis and Peri-Implant Mucositis

The scientific literature is increasingly focused on peri-implant mucositis and peri-implantitis, which are biological outcomes of dental implant treatment.

BACKGROUND/OBJECTIVES

The present study aimed to evaluate the two most critical complications of dental implantation, peri-implant mucositis and peri-implantitis, through the prism of different influencing factors.

METHODS

We followed 40 patients, with a total number of 92 dental implants, divided into three age groups: under 35 years, between 35 and 55 years, and older than 55 years. Patients were also divided into groups according to the time since implant placement: 1-3 years, 4-7 years, and more than 7 years. The patients were examined, and periodontal pocket depth, peri-implant pocket depth, Löe-Silness gingival index, mucosal thickness, and keratinized mucosal width were recorded; bone resorption was measured on radiographs using a 2D image analysis method; and a questionnaire was also conducted.

RESULTS

Bone resorption was highest in the 35-55 age group (3.09 ± 0.04 mm) and for implants placed 4-7 years ago (3.39 ± 0.12 mm). Females had a mean bone resorption of 3.4 ± 0.15 mm and males of 2.45 ± 0.07 mm. Statistically, there was a significant difference only in the Löe-Silness index: the 35-55 age group had the highest values (p = 0.04).

CONCLUSIONS

There were no statistically significant differences between the time since implant placement and the degree of bone resorption, nor between sexes. Peri-implant inflammation may occur at any age, regardless of the lifetime of the implants.

Prevalence, risk indicators, and clinical characteristics of peri-implant mucositis and peri-implantitis for an internal conical connection implant system: A multicenter cross-sectional study

BACKGROUND

Peri-implant disease prevalence is associated with a multifactorial etiology and distinct clinical characteristics of inflammation.

METHODS

The present study aimed to assess the prevalence of peri-implant diseases, identify related risk indicators, and associate specific clinical characteristics to peri-implant biological complications in the medium term. Peri-implant diseases were classified according to established case criteria. Patients' data, implant and/or prosthetic features, and maintenance records were collected. Clinical characteristics such as bleeding on probing (BOP), suppuration (SUPP), keratinized mucosa (KM), probing depth (PD), marginal recession (MR), and modified plaque index (mPI) were recorded.

RESULTS

Ninety-nine patients with 266 implants with a mean functional duration of 30.26 months were evaluated. Peri-implant mucositis and peri-implantitis prevalence totaled to 49.5% and 15.15% (patient level), respectively. Peri-implant mucositis was associated with osteoporosis (odds ratio [OR] 6.09), age (OR 0.97), diabetes mellitus (OR 3.09), cemented-retained prosthesis (OR 3.81), and partial prosthesis (OR 2.21). Peri-implantitis was associated with osteoporosis (OR 7.74) and periodontitis (OR 2.74), cemented prosthesis (OR 10.12), partial and full arch prostheses (OR 12.35 and 19.86), implant diameter (OR 3.64), abutment transmucosal height (OR 3.39), and hygiene difficulty (OR 3.14). Furthermore, mPI score 3 (OR 3.27) and PD scores (OR 1.64) were associated with peri-implant mucositis, while mPI score 3 (OR 16.42), KM (OR 1.53), PD (OR 1.81), MR (OR 2.61), and the relationship between KM and PD (OR 0.63) were associated with peri-implantitis.

CONCLUSION

In the medium term, peri-implant diseases were correlated with factors inherent to the patient's conditions, presurgical treatment plan, and hygiene maintenance care. The knowledge of the mentioned factors and featured clinical characteristics can be crucial for disease prevention and establishment of a superior implant therapy prognosis.

Diagnostic measures for monitoring and follow-up in periodontology and implant dentistry

This review discusses the role of diagnostic measures in the lifelong management of periodontal disease and peri-implant complications. After active treatment, these conditions require regular monitoring of the supporting structures of teeth and dental implants to assess bone and soft tissue health over time. Several clinical measures have been developed for the routine assessment of periodontal and peri-implant tissues, including periodontal and peri-implant probing, bleeding on probing, intraoral radiography, biomarker analysis, and microbiological testing. This review highlights the evolution of diagnostic practices, integrating traditional methods with emerging technologies such as resonance frequency analysis and ultrasound imaging to provide a holistic view of peri-implant health assessment. In addition to objective measurements, patient risk factors are considered. The goals of periodontal and peri-implant maintenance are to control disease activity and stabilize tissues through supportive care, which includes diagnostic measures at follow-up visits. This enables clinicians to monitor treatment outcomes, assess health status, and detect recurrence or progression early through routine evaluation, allowing additional interventions, including adjustment of supportive therapy intervals, to further improve and maintain periodontal and peri-implant stability over time.

Influence of an allogenic collagen scaffold on implant sites with thin supracrestal tissue height: a randomized clinical trial

OBJECTIVES

This randomized clinical trial focused on patients with thin peri-implant soft-tissue height (STH) (≤ 2.5 mm) and investigated the impact of an allogenic collagen scaffold (aCS) on supracrestal tissue height and marginal bone loss (MBL).

MATERIAL & METHODS

Forty patients received bone level implants and were randomly assigned to the test group with simultaneous tissue thickening with aCS or the control group. After three months, prosthetic restoration occurred. STH measurements were taken at baseline (T0) and reopening surgery (TR), with MBL assessed at 12 months (T1). Descriptive statistics were calculated for continuous variables, and counts for categorical variables (significance level, p = 0.05).

RESULTS

At T1, 37 patients were available. At T0, control and test groups had mean STH values of 2.3 ± 0.3 mm and 2.1 ± 0.4 mm. TR revealed mean STH values of 2.3 ± 0.2 mm (control) and 2.6 ± 0.7 mm (test), with a significant tissue thickening of 0.5 ± 0.6 mm in the test group (p < 0.03). At T1, control and test groups showed MBL mean values of 1.1 ± 0.8 mm and 1.0 ± 0.6 mm, with a moderate but significant correlation with STH thickening (-0.34), implant position (0.43), history of periodontitis (0.39), and smoking status (0.27).

CONCLUSION

The use of an aCS protocol resulted in soft tissue thickening but did not reach a threshold to reliably reduce MBL compared to the control group within the study's limitations.

CLINICAL RELEVANCE

Peri-implant STH is crucial for maintaining peri-implant marginal bone stability. Marginal bone stability represents a crucial factor in prevention of peri-implantitis development. German register of clinical trial registration number DRKS00033290.

A Single Dose of Piperacillin Plus Tazobactam Gel as an Adjunct to Professional Mechanical Plaque Removal (PMPR) in Patients with Peri-Implant Mucositis: A 6-Month Double-Blind Randomized Clinical Trial

OBJECTIVES

This randomized, placebo-controlled, double-masked clinical trial aimed to evaluate the clinical and microbiological efficacy of professional mechanical plaque removal (PMPR) with or without adjunctive application of piperacillin plus tazobactam gel in the treatment of peri-implant mucositis (PiM) for up to 6 months.

MATERIALS AND METHODS

The study included 31 patients with peri-implant mucositis (bleeding on probing (BoP) > 1 at at least one site at baseline, absence of peri-implant bone loss compared with a previous radiograph). After randomized assignment to test and control groups, patients received full-mouth supragingival scaling with or without piperacillin plus tazobactam gel. Clinical examination was performed at baseline and after 3 and 6 months, and a microbiological examination was performed at baseline and after 3 months.

RESULTS

After six months, both treatment modalities resulted in significant reductions and improvements in clinical parameters at the implant sites. Neither study group achieved a complete resolution of PiM (i.e., BoP ≤ 1 per implant). The number of implants with BoP decreased statistically significantly between subsequent time points (p < 0.001) in both the test and the control group. Significant BoP differences (p = 0.039) were observed between groups at 6 months (difference to baseline) following therapy.

CONCLUSIONS

Within the limitations of the present study, the single use of a slow-release, locally applied antibiotic combination of piperacillin and tazobactam gel, adjunctive to PMPR, showed an improvement in clinical variable of implants diagnosed with PiM. The adjunctive treatment resulted in higher BoP reduction when compared to the control, but no significant differences were observed regarding the changes in other clinical and microbiological parameters.

Influences of standardized clinical probing on peri-implant soft tissue seal in a situation of peri-implant mucositis: A histomorphometric study in dogs

BACKGROUND

Clinical probing is commonly recommended to evaluate peri-implant conditions. In a situation of peri-implant mucositis or peri-implantitis, the peri-implant seal healing from the disruption of soft tissue caused by probing has not yet been studied. This study aimed to investigate soft tissue healing after standardized clinical probing around osseointegrated implants with peri-implant mucositis in a dog model.

METHODS

Three transmucosal implants in each hemi-mandible of six dogs randomly assigned to the peri-implant healthy group or peri-implant mucositis group were probed randomly in the mesial or distal site as probing groups (PH or PM), the cross-sectional opposite sites as unprobed control groups. Histomorphometric measurements of implant shoulder (IS)-most coronal level of alveolar bone contact to the implant surface (BCI), apical termination of the junctional epithelium (aJE)-BCI, mucosal margin (MM)-BCI, and MM-aJE were performed at 1 day, 1 week, and 2 weeks after probing. Apoptosis, proliferation, proinflammatory cytokines, and matrix metalloproteinases (MMPs) of peri-implant soft tissue were estimated by immunofluorescent analysis.

RESULTS

In the PM group, apical migration of junctional epithelium was revealed by significantly decreased aJE-BCI from 1 day to 2 weeks in comparison to unprobed sites (p < 0.05), while no significant differences were found in the PH group. Immunofluorescent analysis showed higher levels of interleukin-1β (IL-1β), IL-6, tumor necrosis factor-α (TNF-α), MMP-1, and MMP-8, together with exaggerated apoptosis and proliferation of peri-implant soft tissue in the PM group.

CONCLUSION

Within the limitations, standardized clinical probing might lead to apical migration of the junctional epithelium in a situation of peri-implant mucositis.

Long-Term Efficacy of Chlorhexidine Gel in Single-Crown Implant Rehabilitation: A Five-Year Follow-Up Study

Chlorhexidine digluconate (CHX) has shown the ability to significantly reduce inflammation and marginal bone loss (MBL) at the 1-year follow-up but limited data exist regarding its long-term efficacy in peri-implant stability. The objective was to compare the long-term effects (5 years of follow-up) of a placebo gel (16 patients in Group A) or a 0.20% CHX gel (15 patients in Group B) used at each previous surgical and prosthetic stage. Control visits were conducted in 2022, investigating the long-term effects by biological, radiological, and clinical evaluation. The data were statistically analyzed. The research achieved a 96.7% implant success rate over five years, but 41.9% of patients did not attend annual oral hygiene check-ups. The average MBL was 1.04 ± 0.39 mm, with no significant differences between the two groups. Notably, patients who attended regular periodontal check-ups experienced significantly less MBL than those who did not (p < 0.05). At five years, direct effects of CHX were absent, with both groups showing moderate bone loss. However, the results suggest that early disinfection could enhance both short- and long-term outcomes. In fact, patients with initial minor MBL due to use of CHX, preserve this advantage also after 5 years of follow-up. Additionally, the data underscore the importance of annual check-ups in early detection and management of biological complications.

Incidence of Peri-Implantitis, Technical and Biological Complications of Single Implants Placed with Flap or Flapless Surgery-A 10-12-Year Case-Series

BACKGROUND

Long-term follow-up of single implants and crowns is scarce, especially when inserted using flapless surgery.

AIM

Evaluate survival, peri-implantitis incidence, and technical/biologic complications of solitary implants/crowns after 10-12 years of function.

MATERIAL AND METHODS

49 patients with 53 single implants, initially operated with a one-stage flap (F) or flapless (FL) surgery and delayed loading, were recalled. Implant survival, radiographic bone-level changes compared to baseline, peri-implant health, and soft tissue aesthetics were registered. Differences in implant level between and within groups were statistically tested using the Mann-Whitney U-Test and Wilcoxon Signed Ranks Test, respectively.

RESULTS

36 patients with 40 implants were reassessed, yielding 100% implant and 97.5% crown survival. The bone loss in F (n = 19) was 0.56 mm (SD 0.89; range -0.9-2.02) and -0.85 mm (SD 0.98; range -2.84-0.53) in FL (n = 21), indicative of bone gain in FL (p = 0.003), the latter due to a difference at baseline but bone-level was comparable (p = 0.126). Groups were comparable for probing pocket depth (PPD); (3.32 vs. 3.19 mm), Bleeding Index (BI); (0.15 vs. 0.22), and gingival recession; (0.38 vs. 0.17 mm). According to international criteria, the peri-implantitis incidence was 0%, but 32.5% of the implants/crowns experienced biological or technical complications irrespective of surgical technique.

CONCLUSIONS

Solitary implants and crowns show good long-term clinical outcomes and peri-implant health. Flapless surgery is a good alternative to conventional in straightforward cases with sufficient bone volume and proper treatment planning.

Peri-implant diseases diagnosis, prognosis and dental implant monitoring: a narrative review of novel strategies and clinical impact

BACKGROUND

The diagnosis of peri-implantar and periodontal relies mainly on a set of clinical measures and the evaluation of radiographic images. However, these clinical settings alone are not sufficient to determine, much less predict, periimplant bone loss or future implant failure. Early diagnosis of periimplant diseases and its rate of progress may be possible through biomarkers assessment. Once identified, biomarkers of peri-implant and periodontal tissue destruction may alert the clinicians before clinical signs show up. Therefore, it is important to consider developing chair-side diagnostic tests with specificity for a particular biomarker, indicating the current activity of the disease.

METHODS

A search strategy was created at Pubmed and Web of Science to answer the question: "How the molecular point-of-care tests currently available can help in the early detection of peri-implant diseases and throws light on improvements in point of care diagnostics devices?"

RESULTS

The PerioSafe® PRO DRS (dentognostics GmbH, Jena) and ImplantSafe® DR (dentognostics GmbH, Jena ORALyzer® test kits, already used clinically, can be a helpful adjunct tool in enhancing the diagnosis and prognosis of periodontal/peri-implantar diseases. With the advances of sensor technology, the biosensors can perform daily monitoring of dental implants or periodontal diseases, making contributions to personal healthcare and improve the current status quo of health management and human health.

CONCLUSIONS

Based on the findings, more emphasis is given to the role of biomarkers in diagnosing and monitoring periodontal and peri-implant diseases. By combining these strategies with traditional protocols, professionals could increase the accuracy of early detection of peri-implant and periodontal diseases, predicting disease progression, and monitoring of treatment outcomes.

Tetracycline impregnated bone grafts in the management of peri-implantitis and guided bone regeneration around dental implants: A systematic review

Background

Rehabilitation of dental arches with the help of dental implants has been revolutionary and a significant part of research is devoted to increasing its success rate. One of the most common causes of failure of dental implants is peri-implantitis caused due to microbial invasion. Newer strategies are being adapted for the treatment of peri-implantits and recent surgical management with the help of antibiotic-impregnated bone grafts shows a promising future.

Aim and objectives

This study aimed to test the efficacy of bone grafts incorporating tetracycline and its derivatives in the treatment of peri-implantits and guided bone regeneration with the estimation of clinical and radiographic parameters.

Methods

A thorough search was made on eminent databases such as PubMed, Embase, Scopus, and Cochrane Library database for published literature on tetracycline impregnated bone grafts used either in the management of peri-implantitis or for guided bone regeneration around dental implants.The measures of outcome were clinical attachment loss or probing depth around dental implants and radiographic bone height.

Results

Nine potentially eligible full-text published articles including case reports, case series, observational studies, and randomized controlled trials were selected for review. Most of the studies reviewed; reported a reduction in probing depth and an increase in bone height and density after placement of tetracycline bone grafts around the dental implant.

Conclusion

The incorporation of tetracycline into the bone grafts shows promising results as an agent of local delivery around dental implants in the management of peri-implantitis and for guided bone regeneration. Future trials are required to produce a body of evidence and to facilitate the translation of this procedure into clinical practice.

Immediate flapless full-arch rehabilitation of edentulous jaws on 4 or 6 implants according to the prosthetic-driven planning and guided implant surgery: A retrospective study on clinical and radiographic outcomes up to 10 years of follow-up

OBJECTIVES

to retrospectively evaluate clinical and radiographic outcomes of immediate, flapless full-arch prostheses, supported by 4/6 implants according to prosthetic-driven planning and guided surgery.

MATERIALS AND METHODS

The study involved 28 edentulous patients (20 female/8 males; average age 67.75 ± 8.627 years), 32 prostheses (17 all-on-4/15 all-on-6) and 164 implants. The Implants survival, prostheses success/survival, peri-implant marginal bone loss, incidence of biological and prosthetic complications were evaluated. Multiple linear regression analysis was performed to analyze the influence of implant and patient characteristics on marginal bone loss.

RESULTS

Cumulative implant survival rate was 89.7% for all-on-four (seven failures) and 99.0% for all-on-six (one failure) after a mean follow-up of 6.46 ± 2.236 years (range 1-10 years). Cumulative prosthesis success rate was 51.5% (58.8% for all-on-four/ 43.8% for all-on-six). Prosthesis survival rate was 88.2% for all-on-four. No failure was registered in all-on-six. Mean value of marginal bone loss was 1.38 ± 0.1.28 mm at 5-year and 2.09 ± 0.56 mm at 10-year follow-up. No difference was found in the mean value of marginal bone resorption between all-on-four (1.56 ± 1.61 mm) and all-on-six (1.20 ± 0.85 mm) (p = 0.104) and between tilted (1.22 ± 1.29 mm) and axial implants (1.44 ± 1.27 mm) (p = 0.385) after 5-year follow-up. The incidence of biological complications was 1.0% in all-on-six (one mucositis) and 10.3% in all-on-four (two peri-implantitis). Prosthetic complications affected teeth of final rehabilitations with 3 detachments, 10 chippings or fractures, and 3 severe occlusal wears.

CONCLUSIONS

Based on the results and within the limitations of the present study, the implant-supported hybrid prosthesis according to prosthetic-driven planning and guided surgery showed to be an efficient, safe, and effective approach to rehabilitate edentulous jaws.

Comparison of the Biological Behavior and Topographical Surface Assessment of a Minimally Invasive Dental Implant and a Standard Implant: An In Vitro Study

The current study aimed to assess the topographical and physical properties of a minimally invasive implant (MagiCore®: MC®, InnosBioSurg, IBS) and to evaluate its biological behavior compared to a gold standard implant (NobelParallel™: NB™, Nobel Biocare™). After surface characterization, the biological behavior assessment was conducted regarding human gingival fibroblasts (hGF) and osteoblast-like cells (MG63). Roughness values for NBTM were Ra = 1.28 µm and for MC® they were Ra = 2.02 µm. Alamar BlueTM assay LIVE/DEADTM staining results indicated equivalent biological development regarding both cell types for the two implants. Significant enhancement was found for hGF ALP activity in the presence of the two tested implants in a time-dependent manner from day 7 to day 14 (** p < 0.01). Alizarin red staining demonstrated significant calcium deposition enhancement when cells were interfaced with the NB™ compared to the MC® implant (** p < 0.05). Moreover, SEM and confocal imaging revealed good cell adhesion with a denser cellular layer on the MC® than the NB™ surface. The MC® cytocompatibility was ranked as equivalent to the gold standard implant despite the surface properties differences. These findings provide new insights about the minimally invasive implant’s biological behavior and its potential clinical implication in different implantology situations.

Implications of considering peri-implant bone loss a disease, a narrative review

BACKGROUND

Peri-implantitis has been suggested to cause significant increasing proportions of implant failure with increasing time.

PURPOSE

To assess whether implant failure rates in long term studies are matching the supposed high prevalence of peri-implantitis.

MATERIAL AND METHODS

This paper is written as a narrative review of the long-term clinical investigations available in the literature.

RESULTS

Some implant systems have seen unacceptable marginal bone loss figures with time coupled to increased implant failure rates, resulting in the withdrawal of these systems. The reasons for such mishap are generally unknown, with the exception of one system failure that was found to be due to improper clinical handling. Modern, moderately rough implant systems have functioned excellently over 10-15 years of follow up with minor problems with marginal bone loss and implant failure rates within a few per cent. Machined implants have functioned adequately over 20-30 years of follow up. Implant failures occur predominantly during the first few years after implant placement. No significant increase of implant failures has been observed thereafter over 20-30 years of follow up. Over the years of our new millennium, scientific and technical advances have allowed the discovery of numerous molecular pathways and cellular interactions between the skeletal and immune system promoting the development of the interdisciplinary field called osteoimmunology. Nowadays, this knowledge has not only allowed the emergence of new etiologic paradigms for bone disease but also a new dynamic approach on the concept of osseointegration and MBL around oral implants, re-evaluating our older disease oriented outlook. This facilitates at the same time the emergence of translational applications with immunological perspectives, scientific approaches based on omics sciences, and the beginning of an era of personalized dental implant therapy to improve the prognosis of oral implant treatment.

CONCLUSIONS

Oral implant systems have been found to function with very good clinical outcome over follow-up times of 20-30 years. Registered implant failures have occurred predominantly during the first few years after implantation, and there has been no significant increase in late failures due to peri-implantitis.

Predicting the Risk of Dental Implant Loss Using Deep Learning

AIM

To investigate the feasibility of predicting dental implant loss risk with deep learning (DL) based on preoperative cone-beam computed tomography.

MATERIALS AND METHODS

Six hundred and three patients who underwent implant surgery (279 high-risk patients who did and 324 low-risk patients who did not experience implant loss within 5 years) from January 2012 to January 2020 were enrolled. Three models, a logistic regression clinical model (CM) based on clinical features, a DL model based on radiography features, and an integrated model (IM) developed by combining CM with DL, were developed to predict the 5-year implant loss risk. The area under the receiver operating characteristic curve (AUC) was used to evaluate the model performance. Time to implant loss was considered for both groups, and Kaplan-Meier curves were created and compared by the log-rank test.

RESULTS

The IM exhibited the best performance in predicting implant loss risk [AUC = 0.90, 95% confidence interval (CI) 0.84-0.95], followed by the DL model (AUC = 0.87, 95% CI 0.80-0.92) and the CM (AUC = 0.72, 95% CI 0.63-0.79).

CONCLUSION

Our study offers preliminary evidence that both the DL model and IM performed well in predicting implant fate within 5 years and thus may greatly facilitate implant practitioners in assessing preoperative risks.

Influence of Periodontitis, Implant, and Prosthesis Characteristics on the Peri-Implant Status: A Cross-Sectional Study

Background

The association between peri-implant diseases and the periodontal, implant, and prosthesis characteristics has been characterized in various ways.

Purpose

The aim of this study was to evaluate the link between the peri-implant and periodontal status and the influence of implant and prosthesis parameters during implant follow-up.

Materials and Methods

One hundred and seven patients with a total of 310 implants that had at least one year of function who were attending periodontal and implant maintenance at a university clinic setting were included in this cross-sectional study. The demographic, periodontal, peri-implant tissue, implant, and prosthesis parameters were recorded. A pocket depth > 4 mm with bleeding on probing defined periodontal/peri-implant soft tissue diseased sites. Analyses were performed at the patient and implant levels using univariable and multivariable mixed regression analysis.

Results

The mean implant follow-up was 7.22 years. At the patient level, the bleeding on probing and pocket depth measurements were more pronounced around the implant than around the teeth. The opposite was observed for plaque and the clinical attachment levels. At the implant level, multivariable analysis showed that the periodontal and corresponding peri-implant tissue parameters, such as diseased sites, were closely related. The implant location, bone level, and number were selectively associated with the implant bone level, while cemented retention and emergence restoration profile influenced the implant pocket depth.

Conclusions

The present study suggested that clinical peri-implant and periodontal soft tissue statuses were different, which could be a consequence of the initial implant and prosthesis healing process. However, during implant follow-up, the peri-implant parameters were predominantly associated with their corresponding periodontal parameters regardless of an association with the implant and prosthesis characteristics. This trial is registered with ClinicalTrials.gov ID: NCT03841656.

Clinical Evaluation of Pink Esthetic Score of Immediately Impressed Posterior Dental Implants

PURPOSE

While comparative outcome results for peri-implant crestal bone levels, mucosal margin position, and peri-implant indices have been reported, no studies are available that evaluate and compare the esthetic result of impressions performed immediately with that of impressions performed of healed implants. The purpose of this cross-sectional study was to evaluate the Pink Esthetic Score (PES) of posterior implants restored with an immediate impression workflow compared to implants restored with a delayed impression workflow.

MATERIAL AND METHODS

Twenty-eight eligible participants who had received a single implant crown either in the premolar or molar regions at least 4 months before the study, were identified by an electronic health record review and scheduled for a single-visit study appointment. Esthetic outcomes were measured using the Pink Esthetic Score (PES). Several local- and prosthesis-related factors were recorded and their association with the selected outcome was assessed. Two-sample t-test was used for comparisons between the groups.

RESULTS

PES ranged between 4 and 12 (mean: 8). No significant difference between immediate (8.36 ± 1.12) and delayed (7.76 ± 2.14) impression workflow groups were seen for the total PES (p = 0.25). In addition, individual comparisons between immediately and delayed impressed implants for mesial papilla (1.27 ± 0.47; 0.88 ± 0.78), distal papilla (0.73 ± 0.65; 0.76 ± 0.83), tissue margin (1.73 ± 0.47; 1.47 ± 0.51), tissue contour (1.27 ± 0.65; 0.82 ± 0.64), alveolar process (0.82 ± 0.60; 1.00 ± 0.87), color (1.27 ± 0.65; 1.29 ± 0.69), and texture (1.36 ± 0.50; 1.53 ± 0.62) did not show significant differences.

CONCLUSIONS

The current study suggests that the Pink Esthetic Score is not significantly different between single posterior implants impressed with the immediate and delayed implant workflows. This article is protected by copyright. All rights reserved.

The use of implant-level connection in screw-retained fixed partial dentures: A 3-year randomised clinical trial

OBJECTIVES

This randomised controlled trial compares the 3-year outcomes, that is, marginal bone-level (MBL) changes and clinical parameters, between an abutment-level (AL) and implant-level (IL) connection for implants with an internal conical connection (ICC) supporting a screw-retained fixed partial denture.

MATERIAL AND METHODS

Fifty patients with 119 implants were randomly allocated to either the AL or IL group. Radiographic and clinical examinations were performed after one, two, and 3 years. A linear mixed model was used to evaluate the differences between groups.

RESULTS

The MBL change was not significantly different between the groups at any point. The MBL was 0.12 ± 0.31 mm (AL) and 0.23 ± 0.26 mm (IL) after 1 year; 0.15 ± 0.34 mm (AL) and 0.17 ± 0.22 mm (IL) after 2 years; 0.18 ± 0.39 mm (AL) and 0.15 ± 0.21 mm (IL) after 3 years. The bleeding on probing was 43.44 ± 39.24% (AL) and 58.19 ± 41.20% (IL) after 1 year; 35.78 ± 39.22% (AL) and 50.43 ± 41.49% (IL) after 2 years; 51.27 ± 44.63% (AL) and 49.57 ± 37.31% (IL) after 3 years and was significantly different (p = .025) between 1 and 2 years. The probing depth showed a significant difference at each time point while the plaque was not significant between the groups. The overall technical, biological and prosthetic complication rates were 5.04%, 3.36%, and 16.00%, respectively.

CONCLUSIONS

The MBL change was similar in the groups. The slight differences in the soft tissue complications between the groups are likely not of clinical relevance. An IL connection is considered to be a valid alternative to an AL set-up in ICC implants.

Intra- and Inter-Examiner Repeatability of Diagnostic Peri-implant Clinical Measurement: A Pilot Study

Despite the crucial role of examiner reliability on quality research and practice, there is still limited literature analyzing factors affecting examiner variability of peri-implant clinical measurements. The present study investigated clinical peri-implant parameters to quantify their repeatability and investigate factors that may affect their accuracy. Thirty-three implants were examined by four operators. Peri-implant probing depth (PD), recession (REC) and gingival index (GI) were measured for agreement and included for analysis. Agreement was quantified using intraclass correlation coefficients (ICC; 95% CI); mixed linear and logistic regressions were used to assess additional variables. The overall inter-examiner agreement was comparable between PD (0.80) and REC (0.78), but significantly worse for GI (0.45) (p<0.001). Similarly, the intra-examiner agreement was similar for PD (0.81) and REC (0.80), but significantly worse for GI (0.57) (p<0.05). The magnitude of PD did not influence agreement. In contrast, increasing disagreement was noted for positive REC (OR: 3.0), negative REC (OR: 4.8) and lower GI (OR: 4.4). The incidence of bleeding on probing and severity of GI increased for deeper PD (0.113 unit increase per mm). Negative and positive values of recession and lower GI were associated with increasing disagreement. Radiographic bone loss, restoration contour and implant diameter did not impact PD accuracy within this study. In conclusion, within the limitations of the study, GI measurements presented higher variability than PD and REC. PD and GI were associated with one another and increased after multiple measurements.

Single implant-supported two-unit cantilever fixed partial dentures in the posterior region: a retrospective case series with a mean follow-up of 6.5 years

Background

The aim of this retrospective study was to evaluate the implant survival, clinical and radiographic outcomes, and patient satisfaction of single implant-supported two-unit cantilever fixed partial dentures in the posterior region.

Methods

Patients who received a single implant-supported fixed partial denture with a cantilever in the posterior region between January 2004 and February 2018 were included. Survival rate of the implants and the fixed partial dentures and data regarding the marginal bone level, presence of plaque, calculus, bleeding on probing, mucosa health, pocket probing depth, and patient satisfaction were collected during an evaluation visit. Complications were recorded from the medical records.

Results

Twenty-three patients (mean age 64 ± 13 years) with 28 implants could be included in the study. The mean follow-up period was 6.5 ± 4.8 years at the time of data collection. The survival rate of the implants and fixed partial dentures was 100%. Mean marginal bone loss for the mesial and distal side of the implants was 0.41 mm (SD 1.18 mm) and 0.63 mm (SD 0.98 mm) respectively. A high prevalence of peri-implant-mucositis (89.3%) and peri-implantitis (17.9%) was observed as well as a limited number of technical complications. Patients were quite satisfied, as reflected by a mean VAS score of 94.0 ± 7.2 points (range 0–100) and a OHIP-NL49 score of 10.8 (range 0–196).

Conclusions

Single implant-supported fixed partial dentures with a mesial or distal cantilever can be a predictable treatment option in the posterior region, with stable peri-implant bone levels, minor technical complications, and very content patients. However, the prevalence of peri-implant mucositis and peri-implantitis was high.

Trial registration

ISRCTN, ISRCTN79055740, Registered on March 14, 2021 – —Retrospectively registered.

The Manufacture and Characterization of Silver Diammine Fluoride and Silver Salt Crosslinked Nanocrystalline Cellulose Films as Novel Antibacterial Materials

There is an unmet need for biocompatible, anti-infective, and mechanically strong hydrogels. This study investigated the use of poly vinyl alcohol (PVA), polysaccharides, and nanocrystalline cellulose (CNC) to deliver silver in a controlled manner for possible use against oral or wound bacteria. Silver was included in solvent cast films as silver diammine fluoride (SDF) or as nitrate, sulphate, or acetate salts. Hydrogel formation was assessed by swelling determinations and silver release was measured using inductively coupled plasma methods. Antibacterial studies were performed using Gram-positive and negative bacteria turbidity assays. PVA formed homogenous, strong films with SDF and swelled gently (99% hydrolyzed) or vigorously with dissolution (88% hydrolyzed) and released silver slowly or quickly, respectively. CNC-SDF films swelled over a week and formed robust hydrogels whereas CNC alone (no silver) disintegrated after two days. SDF loaded CNC films released silver slowly over 9 days whereas films crosslinked with silver salts were less robust and swelled and released silver more quickly. All silver loaded films showed good antibacterial activity. CNC may be crosslinked with silver in the form of SDF (or any soluble silver salt) to form a robust hydrogel suitable for dental use such as for exposed periodontal debridement areas.

Association of Self-Rated Pain with Clinical Peri-Implant Parameters and Cytokine Profile in Smokers and Never Smokers with and without Peri-Implantitis

To examine the association between self-perceived pain (SPP), clinical and radiographic peri-implant parameters, and biomarker levels among smokers and never smokers with and without peri-implantitis. Sixty individuals (20 smokers with peri-implantitis [group-1], 20 never smokers with peri-implantitis [group-2] and 20 never smokers without peri-implantitis [control-group]) were included. SPP was evaluated using a numeric pain rating scale (NPRS). Peri-implant plaque index (PI), probing depth (PD), and bleeding on probing (BOP) were recorded. After obtaining the samples, the levels of TNF-α, MMP-1, and IL-8 were measured. The mean SPP score in group-1, group-2, and the control group was 1.3 ± 1, 3.4 ± 1, and zero, respectively. The peri-implant mean PD (p < 0.05), BOP (p < 0.05), PI (p < 0.05), and crestal bone loss (CBL) (p < 0.05) were significantly higher among test groups than the control group. The levels of TNF-α, MMP-1, and IL-8 were significantly raised among group-1 and group-2 than the control group. A significant correlation between increasing SPP and PICF TNF-α, MMP-1, and IL-8 levels was observed based on regression analysis. Proinflammatory biomarkers were higher in smokers with peri-implantitis than never smokers with and without peri-implantitis, with a significant association between the proinflammatory cytokines and SPP.

Cross-sectional evaluation of clinical and immunological parameters at partially microgrooved vs machined abutments in humans

OBJECTIVE

The objective of the present study was to examine the clinical and immunological parameters in samples collected from the peri-implant crevicular fluid (PICF) of machined titanium (M) abutments compared to titanium abutments with a laser-microtextured surface (LMS) on dental implants.

MATERIAL AND METHODS

A total of 40 patients with one titanium implant, half of them (n=20) provided with a M abutment (control group) and the other half (n=20) with LMS abutments (test group), were included in the study. Clinical parameters pocket probing depth (PD), full-mouth plaque score (FMPS), radiographic bone loss (RBL), clinical attachment level (CAL), mucosal recession (MR), bleeding on probing (BOP), and width of keratinized mucosa (KM) were evaluated. The peri-implant sulcus fluid was analyzed for cytokines IL-1α, IL-1β, IL-6, IL-8, and IL-10 via flow cytometry.

RESULTS

Clinical evaluation demonstrated no significant difference of PD (mean LMS = 3.50 mm/SD 0.95 mm vs mean M = 3.45 mm/SD 0.76 mm (p=0.855)), MR (mean LMS = 0.30 mm/SD 0.57 mm vs mean M = 0.35 mm/SD 0.67 mm (p=0.801)), CAL (mean LMS = 3.60 mm/SD 1.14 mm vs mean M = 3.55 mm/SD 0.89 mm (p=0.878)), and KM (mean LMS = 2.03 mm/SD 1.08 mm vs mean M = 2.13 mm/SD 0.92 mm (p=0.754)) between LMS and M abutments. LMS abutments showed less BOP than M abutments (26.7% vs 30.8%), but statistically not significant (p = 0.2235). Radiographic bone loss (mean LMS = 0.22 mm/SD 0.44 mm vs mean M = 0.59 mm/SD 0.49 mm) was reduced in the test group in comparison with the control group (p=0.016). In the collected PICF, the levels of pro-inflammatory cytokines IL-1α (median LMS = 180.8 pg/ml vs M = 200.9 pg/ml (p=0.968)) and IL-1β (median LMS = 60.43 pg/ml vs M = 83.11 pg/ml (p=0.4777)) were lower, and the levels of IL-6 (median LMS = 180.8 pg/ml vs M = 200.9 pg/ml (p<0.0001)) were significantly lower in the test group. In contrast, the levels of IL-8 (median LMS = 255.7 pg/ml vs M = 178.7 pg/ml (p=0.3306)) were higher in the test group, though not significantly. The levels of anti-inflammatory IL-10 were significantly increased in the test group (LMS median = 0.555 pg/ml vs M median = 0.465 pg/ml (p=0.0365)). IL-1β showed a significant correlation to radiologic bone loss (p=0.0024). The other variables IL-1α, IL-6, IL-8, and IL-10 had no significant correlation to radiological bone loss.

CONCLUSION

Within the limitations of this study, titanium implants provided with laser-microtextured surface abutments seem to demonstrate less pro-inflammatory and more anti-inflammatory activity and to show reduced radiographic bone loss compared to machined titanium abutments.

CLINICAL RELEVANCE

The use of laser-microtextured surface abutments might have the potential to support peri-implant tissue health.

Evaluation of clinical performance and survival rate of Straumann dental implants in Saudi Population based on cross-sectional study

Risk indicators of peri-implantitis is still contradictory and somehow unclear in present literature therefore efforts should be done for better understanding of the exact etiology of peri-implant disease progression. The present study aimed to assess risk indicators associated with peri-implantitis by observing the changes in several periodontal parameters after implant placement. This cross-sectional study included 213 female and 271 male patients aged 26–87 years, who received 484 titanium implants (Straumann, Switzerland) at King Saud University’s Dental College, Saudi Arabia. Patients were called for dental visits. During these visits; full clinical and radiographic assessment of implants were done. The periodontal pocket depth (PPD) was greater around implants placed at grafted sites than non-grafted sites and around bone-level implants than tissue-level implants. The plaque index (PI) was associated with poor oral hygiene. There was a strong association between graft (yes/no) and bleeding on probing (BOP). Patients with good oral hygiene showed high radiographic bone stability. Keratinized tissue width < 2 mm was associated with a higher PPD, higher PI, higher BOP, more edematous gingiva, and more exposed implant threads on radiography. In patients receiving implants, poor oral hygiene status and inadequate keratinized tissue level can be proposed as risk indicators for developing periimplantitis due to strong association found between them and developments of peri-implantitis.

Self-reported prevalence of periodontal disease among the Spanish population and immigrants: 2006, 2011/12 and 2017: a population-based study

BACKGROUND

Periodontal disease is one of the most common pathologies in the population. Self-reporting has been used as a diagnostic tool in large populations, among other reasons, to detect the needs of potentially vulnerable groups. This study evaluated the prevalence of periodontal disease in people of Spanish nationality and immigrants in Spain.

METHODS

This population-based, cross-sectional study was carried out using data obtained from National Health Interview Surveys (NHSs) carried out in 2006, 2011/2012 and 2017 in Spain. Subjects aged 16 years and older were included in the NHS-2006 and aged 15 years and older were included in the other NHSs. The following variables were self-reported by the participants: gum bleeding, tooth mobility, tooth extraction and missing teeth. Chi-square homogeneity tests were performed to assess the main associations between the independent variable (nationality) and the dependent variables (bleeding gums, tooth mobility, tooth extraction and missing teeth). Multinomial logistic regression models were constructed to evaluate the influences of the variables age and sex and their interactions on the main associations.

RESULTS

A total of 115,123 participants were included in the NHS-2006 (n = 37,327, 11.38% immigrants), NHS-2011/12 (n = 38,727, 14.39% immigrants) and NHS-2017 (n = 39,069, 13.71% immigrants). The variables directly related to periodontal disease were gum bleeding and tooth mobility. These were significantly associated with nationality in the NHS-2006 and NHS-2017 cohorts. In the NHS-2011/12 cohort, only tooth mobility was associated with nationality. After adjustments for sex, age, and their interactions, immigrant status was associated with increased odds of bleeding in only the NHS-2006 cohort (RR = 1.65, 95% CI 1.38-1.99, p = 0.000).

CONCLUSION

Immigrants in Spain have a lower probability of developing signs associated with periodontal disease than the Spanish population. Among the immigrant cohort, females and those in adult age groups had lower prevalence rates than their counterparts.

Clinical Evaluation of Crestal Bone Levels, Peri-Implant Indices, and Mucosal Margin Position of Immediately Impressed Posterior Dental Implants: A Cross-Sectional Study

PURPOSE

This is a cross-sectional clinical study to evaluate crestal bone levels, mucosal margin position, probing depths, bleeding on probing, and plaque and bleeding indices of implants restored with an immediate impression workflow compared to implants restored with a delayed impression workflow.

MATERIALS AND METHODS

Patients who had received a posterior single implant crown in the premolar and molar regions were identified and scheduled for a single-visit study appointment. Outcome measurements included soft tissues peri-implant indices, peri-implant mucosal margin position, and crestal bone levels. Several systemic-, local-, and prosthesis-related factors were recorded. Bitewing radiographs were used to assess crestal bone levels. Wilcoxon rank sum test was used to compare the medians of continuous measurements and Pearson chi-square test (or Fisher's exact test) was used to compare the distributions of categorical variables between the two groups.

RESULTS

Twenty eight patients were included. Crestal bone levels, peri-implant mucosal margin position and peri-implant soft tissue parameters for the immediately impressed group were not statistically different from the delayed impressed group, except for probing depth for the immediately impressed buccal site, which was less than that of the delayed group. Mesial bone level for cement-retained crowns was significantly more coronal than for screw-retained ones.

CONCLUSIONS

While an isolated statistical difference was found in probing depth, the current study suggests that there is no clinically significant difference between implants impressed with immediate and delayed implant workflows when considering crestal bone levels, peri-implant mucosal margin position, and most peri-implant indices.

Current Concepts on the Pathogenesis of Peri-implantitis: A Narrative Review

As implant treatment has been integrated in contemporary dental practice, complications with the forms of peri-implant mucositis and peri-implantitis have also increased in prevalence. Peri-implantitis is the more severe biological complication and is defined as an inflammatory disease affecting peri-implant tissues resulting in bone and eventually implant loss. In addition, the treatment of peri-implantitis has currently become a substantial global economic burden. In the current study, a search was conducted in several electronic databases using specific keywords relevant to the article's main topic. An increasing number of scientific reports have investigated the etiopathology of peri-implant diseases, focusing mainly on peri-implantitis. Microbial biofilm consists an important etiological factor of peri-implant pathology analogous to periodontal diseases. Although several data confirm that peri-implant infections are dominated by gram-negative bacteria, similar to periodontal infections, there is evidence that some cases may harbor a distinct microbiota, including opportunistic microorganisms and/or uncultivable species. Additionally, data support that several parameters, such as genetic predisposition of individual patients, occlusal overload, and local factors such as titanium particles and excess cement, may be implicated in peri-implantitis pathogenesis. Simultaneously, the release of titanium metal particles and their biological consequences or the presence of excess cement in the adjacent peri-implant tissues have also been suggested as factors that contribute to peri-implant pathology. A specific line of research also indicates the role of foreign body response to implant installation. This narrative review aims to discuss the current concepts of etiopathogenetic factors implicated in peri-implantitis.

Implant survival and biologic complications of implant fixed complete dental prostheses: An up to 5-year retrospective study

STATEMENT OF PROBLEM

Limited information is available on the association between prosthesis-associated risk factors and biologic complications for patients with implant fixed complete dental prostheses (IFCDPs).

PURPOSE

The purpose of this retrospective study was to assess the implant survival and biologic complications of IFCDPs up to 5 years of follow-up.

MATERIAL AND METHODS

Patients who had received IFCDPs between August 1, 2009 and August 1, 2014 were identified through an electronic health record review. Those who consented to participate in the study attended a single-visit study appointment. Clinical and radiographic examinations, intraoral photographs, and peri-implant hard and soft tissues parameters were assessed. Only prostheses which could be removed during the study visit were included. Associations between biologic complications and prosthetic factors, such as time with prosthesis in place, prosthesis material, number of implants, cantilever length, and type of prosthesis retention, were assessed.

RESULTS

A total of 37 participants (mean ±standard deviation age 62.35 ±10.39 years) with 43 IFCDPs were included. None of the implants had failed, leading to an implant survival of 100% at 5.1 ±2.21 years. Ten of the prostheses were metal-ceramic (Group MC) and 33 were metal-acrylic resin (Group MR). Minor complications were more frequent than major ones. Considering minor complications, peri-implant mucositis was found in 53% of the implant sites, more often in the maxilla (P=.001). The most common major biologic complication was peri-implantitis, which affected 4.0% of the implants, more often in the mandible (P=.025). Peri-implant soft tissue hypertrophy was present 2.79 times more often (95% CI: 1.35 - 5.76, P<.003) around implants supporting metal-acrylic resin prostheses than metal-ceramic ones, with the former type also showing significantly more plaque accumulation (P<.003).

CONCLUSIONS

Biologic complications such as soft tissue hypertrophy and plaque accumulation were more often associated with metal-acrylic resin prostheses. Peri-implant mucositis occurred more often under maxillary IFCDPs, while peri-implantitis appeared more common around mandibular implants.

On marginal bone level changes around dental implants

BACKGROUND

Peri-implant bone level values have been used as the clinical standard of reference to describe the status of a dental implant, despite the fact that their significance for the long-term survival of the implant has never been properly assessed.

PURPOSE

To challenge the assumption that the natural course of peri-implant bone loss is the loss of the implant.

MATERIALS AND METHODS

This article is a narrative review on reasons and interpretations of marginal bone level changes around dental implants.

RESULTS AND CONCLUSIONS

Different views regarding the pattern and progression of marginal bone loss depending on dental specialties have been identified. However, the present finding of a negative correlation between an increasing cumulative marginal bone loss and a decreasing risk of implant failures over time indicates that peri-implant marginal bone loss does not necessarily represent a condition of disease. Reduction of marginal bone levels may be observed in a majority of patients during follow-up time, with only a minority of those patients losing implants and implant-supported prostheses in the long term. Bone level changes seem often to occur as a consequence of physiological processes and/or as an adaptation to altered external as well as host response factors. Periodical radiological assessments of implant-restorations remain a valid diagnostic tool for the detection of potential implant fractures, loss of osseointegration, screws working loose and for the detection of the few cases with advanced, continuously progressing marginal bone loss during time. The detection of peri-implant marginal bone loss at one time point should not be immediately considered as a sign of ongoing pathology and of an increased risk of future loss of the implant in question.

Clinical findings and history of bone loss at implant sites

OBJECTIVES

The aim of the present study was to evaluate whether clinical findings at implant sites are relevant as screening tests for a history of marginal bone loss.

MATERIAL AND METHODS

427 patients provided with implant-supported reconstructions 9 years earlier were evaluated clinically (probing pocket depth (PPD), bleeding on probing (BoP)) and radiographically. A history of bone loss was confirmed through baseline documentation. Diagnostic accuracy was evaluated through receiver operating characteristic curves and multi-level regression analyses. Results were expressed as sensitivity/specificity, area under the curve, and odds ratios.

RESULTS

While the sensitivity of PPD in regard to bone loss was low, specificity was generally high. Multi-level modeling revealed that each additional millimeter of PPD corresponded to an additional bone loss of 0.30 mm (95% CI 0.27; 0.33). The sensitivity of BOP in regard to bone loss >2 mm was 80.9% (95% CI 73.9; 86.7), while the specificity was 42.2% (95% CI 39.6; 44.8).

CONCLUSIONS

Clinical parameters at implant sites obtained at a single time point were associated with a history of marginal bone loss. While BoP demonstrated a high level of sensitivity, the sensitivity of PPD was generally low. The present data suggest that BoP is a relevant screening test for history of bone loss.

Outcome of peri-implant maintenance care in patients with an implant-supported lower denture-A 3.5-year retrospective analysis

Background

Implant‐supported overdentures represent a successful treatment for edentulous patients. As early diagnosis, detection and supportive care are considered key factors for the prevention of peri‐implant diseases, consistent maintenance of these implants is becoming increasingly relevant.

Purpose

This retrospective analysis evaluated a cohort of edentulous patients with a mandibular implant‐supported overdenture over a period of 3.5 years during which the peri‐implant tissues were assessed.

Materials and Methods

A total of 108 patients that had consistently adhered to the annual maintenance appointments was selected. The clinical peri‐implant pocket probing depth (PiPPD) and peri‐implant bleeding on probing score (PiBOP) were investigated. Data from the 3.5‐year follow‐up were compared to data from the baseline assessment.

Results

A 100% implant survival was reported after 3.5 years. The mean PiBOP showed a significant decrease over time (P = .028). The mean PiPPD was found significantly deeper for male patients both at baseline (P = .004) and 3.5‐year follow‐up (P < .001). Besides, the PiPPD for locator anchorages was found significantly deeper compared to ball anchorages at the 3.5‐year follow‐up (P = .026).

Conclusion

In those patients that adhered to the annual maintenance visits during the 3.5 years after implant surgery a stable peri‐implant condition was observed. As future consideration, the comparison of the clinical outcomes of patients participating in the maintenance program with those that did not would make this observation even more meaningful.

Are marginal bone level changes around dental implants due to infection?

BACKGROUND

Peri-implant bone level values have been used as the clinical standard of reference to describe the status of a dental implant. Reduction of marginal bone levels in association with bleeding on probing have been claimed to be a sign of pathology and an indication of treatment needs.

PURPOSE

To assess the available evidence that peri-implant bone loss is caused by infection.

MATERIALS AND METHODS

This article is a narrative review on the interpretation of marginal bone level changes around dental implants as a consequence of infection.

RESULTS AND CONCLUSIONS

There is evidence that plaque accumulation induces an inflammatory reaction in the peri-implant soft tissues and that resumption of plaque control measures results in the reduction of the inflammation. Since plaque is always present in the oral cavity, a cause-effect relationship between plaque accumulation and peri-implantitis, defined as inflammation of the peri-implant soft tissues associated with marginal bone loss has been difficult to validate and has not been proven so far. There is no evidence of the mechanisms involved in the tissue reactions resulting in the conversion from a state of an inevitable inflammation contained in the soft tissues to a state of inflammation involving the loss of peri-implant marginal bone. There is today no consensus whether implants should be expected to be surrounded by tissues which are completely free from inflammation, or that an "immune-driven", chronic, subclinical inflammation should be expected at the foreign body implant. The infectious origin theory appears to be mainly supported by ligature-induced experimental peri-implantitis investigations in animal models that suffer of several methodological problems, and therefore, provide misleading information with regards to human clinical applications in large, routine populations.

Clinical and radiographic evaluation of implant-supported single-unit crowns with cantilever extension in posterior areas: A retrospective study with a follow-up of at least 10 years

BACKGROUND

Implant-supported restorations with cantilever extension may display high rates of biological and technical complications.

PURPOSE

To report the outcomes of single-unit crowns with cantilever extension (SCCs).

MATERIALS AND METHODS

Patients with SCCs were reevaluated after ≥10 years of loading. Radiographic marginal bone levels (mBLs) at baseline (ie, delivery of SCCs) and follow-up were calculated and compared between implant surfaces adjacent to and distant from the cantilever extension. Implant survival and success rates were calculated.

RESULTS

Twenty-one patients with 25 SCs supported by 25 implants were reevaluated after a mean of 13.6 ± 3.8 years (range: 10-19 years). No implants were lost. The mean overall mBLs changed from 0.99 mm ± 0.95 at baseline to 0.95 mm ± 0.99 at follow-up (p = 0.853). The mean pocket probing depths changed from 3.39 mm ± 0.62 at baseline to 3.34 mm ± 0.54 at follow-up (p = 0.635). Loss of retention occurred 3× in 2 patients (14.3%). At follow-up, peri-implant health was diagnosed in 10 (48%) and peri-implant mucositis in 11 (52%) patients, respectively.

CONCLUSIONS

Within the limitations of the present study, the use of implant-supported SCs with cantilever extension in posterior areas represents a reliable long-term treatment option with a 100% implant survival rate and minimal marginal bone level changes.

Hyaluronic acid reduces inflammation and crevicular fluid IL-1β concentrations in peri-implantitis: a randomized controlled clinical trial

Purpose

This study investigated the effects of hyaluronic acid (HA) on peri-implant clinical variables and crevicular concentrations of the proinflammatory biomarkers interleukin (IL)-1β and tumor necrosis factor (TNF)-α in patients with peri-implantitis.

Methods

A randomized controlled trial was conducted in peri-implantitis patients. Patients were randomized to receive a 0.8% HA gel (test group), an excipient-based gel (control group 1), or no gel (control group 2). Clinical periodontal variables and marginal bone loss after 0, 45, and 90 days of treatment were assessed. IL-1β and TNF-α levels in crevicular fluid were measured by enzyme-linked immunosorbent assays at baseline and after 45 days of treatment. Clustering analysis was performed, considering the possibility of multiple implants in a single patient.

Results

Sixty-one patients with 100 dental implants were assigned to the test group, control group 1, or control group 2. Probing pocket depth (PPD) was significantly lower in the test group than in both control groups at 45 days (control 1: 95% CI, −1.66, −0.40 mm; control 2: 95% CI, −1.07, −0.01 mm) and 90 days (control 1: 95% CI, −1.72, −0.54 mm; control 2: 95% CI, −1.13, −0.15 mm). There was a trend towards less bleeding on probing in the test group than in control group 2 at 90 days (P=0.07). Implants with a PPD ≥5 mm showed higher levels of IL-1β in the control group 2 at 45 days than in the test group (P=0.04).

Conclusions

This study demonstrates for the first time that the topical application of a HA gel in the peri-implant pocket and around implants with peri-implantitis may reduce inflammation and crevicular fluid IL-1β levels.

Trial Registration

ClinicalTrials.gov Identifier: NCT03157193

Assessment of Peri-Implant Soft Tissues Conditions around Short and Ultra-Short Implant-Supported Single Crowns: A 3-Year Retrospective Study on Periodontally Healthy Patients and Patients with a History of Periodontal Disease

The aim of this retrospective study was to evaluate implant survival, marginal bone loss and peri-implant complications in 326 short and ultra-short implants. Implants were placed in the maxillary and mandibular posterior regions of 140 patients with (PP) and without (NPP) a history of periodontal disease. Clinical and radiographic examinations were performed at 3-year recall appointments. The 8.0, 6.0 and 5.0 mm-length implants placed in PP and NPP were respectively 43.75% and 38.46%, 35.10% and 34.19%, 21.15% and 27.35%; 325 implants (one early failure) were rehabilitated with single crowns in 139 patients. Overall implant survival after 3 years of follow-up was 97.55%, 98.08% and 96.61% for PP and NPP (p = 0.46). Crestal bone level variations were not statistically different among PP and NPP; 15.41% of implants presented signs of mucositis, 14.71% and 16.67% in PP and NPP (p = 0.64). Setting the threshold for bone loss at 2 mm after 36 months, peri-implantitis prevalence was 2.2%, 1.96% and 2.63% in PP and NPP (p = 0.7). Overall implant success was 82.39%, 83.33% and 80.7% for PP and NPP (p = 0.55). Short-term outcomes suggest that short and ultra-short locking-taper implants can successfully be restored with single crowns in the posterior jaws both in PP and NPP.

Fixed full-arch maxillary prostheses supported by four versus six implants with a titanium CAD/CAM milled framework: 3-year multicentre RCT

OBJECTIVES

This RCT compares marginal bone level (MBL) change and the clinical parameters after a 3-year function in maxillary implant-supported fixed complete dentures (FCDs) treated with four-implants (4-I) or six-implants (6-I).

MATERIAL AND METHOD

Three centres treated 56 patients with 280 implants allocated to the 4-I or 6-I group. Radiographic and clinical examinations were performed. The primary outcome was to investigate MBL change between the groups.

RESULTS

Implant survival rates were 100% and 99% in the 4-I and 6-I groups, respectively. Considering the clustering effects, the MBL change was not significantly different between the groups over the 3-year follow-up. The MBL in the 4-I group was 0.30 ± 0.50 mm at baseline, 0.24 ± 0.31 mm at 1 year and 0.24 ± 0.38 mm at 3 years. In the 6-I group, MBL was 0.14 ± 0.32 mm at baseline, 0.16 ± 0.35 mm at 1 year and 0.12 ± 0.26 mm at 3 years. There was a statistically significant difference between the groups at BL and 3Y. No significant differences between the groups were reported for clinical parameters at each time point as well as in between the visits. The technical and biological complications rates were 1.6% and 6.0%, respectively. Prosthetic complications affected 25 FCDs (47.2%).

CONCLUSION

Marginal bone level change revealed a stable condition in the 3-year period in the two groups. Few technical and biological complications occurred apart from the chipping/fracture of the prosthetic teeth. Four-implant is a feasible solution if the rehabilitation is oriented towards the most cost-effective treatment and towards avoiding bone augmentation procedures. Clinicians have to consider the potential required visits for prosthetic maintenance.

Multivariate analysis of the influence of prosthodontic factors on peri-implant bleeding index and marginal bone level in a molar site: A cross-sectional study

BACKGROUND

Peri-implant tissue condition can result from prosthodontic, surgical and bacteriological factors.

PURPOSE

This study investigated the effects of prosthodontic factors on peri-implant tissue.

MATERIALS AND METHODS

Subjects were 140 patients with 310 implants from Osaka University Dental Hospital. Prosthodontic factors examined were the connection type, the suprastructure retention type, the material of the abutment and the mesiodistal and buccolingual prosthetic form of the superstructure as emergence angle. The objective variables were the modified bleeding index (mBI) and marginal bone level (MBL). Statistical analysis was used as a generalized estimation equation.

RESULTS

The taper joint had a significantly smaller MBL than the butt joint (P < .001). There was no significant difference in mBI and MBL between cement and screw retaining. Zirconium and titanium resulted in a significantly smaller mBI than gold alloy (zirconium/gold alloy: P = .037, titanium / gold alloy: P = .021), but there was no significant difference in the MBL. Both mBI and MBL tended to be smaller when the emergence angle was around 20° to 40°, although this difference was not significant.

CONCLUSION

As a result of multivariate analysis, our findings suggest that to reduce MBL from the perspective of prosthodontic factors it is preferable to use an implant with a taper joint connection positioned with an emergence angle of 20° to 40°.

Surface functionalization of titanium substrates with Deoxyribonuclease I inhibit peri-implant bacterial infection

This study aimed to investigate the effect of Deoxyribonuclease I (DNase I) coating on initial adhesion and biofilm formation of peri-implant bacteria. Titanium (Ti), Ti-polydopamine (Ti-PDOP), Ti-PDOP-DNase I and Ti-PDOP-inactivated DNase I samples were studied. The FE-SEM, EDS and XPS were used to confirm that DNase I was coated onto Ti. The initial adhesion and biofilm formation of Aggregatibacter actinomycetemcomitans (A.a) and Fusobacterium nucleatum (F.n) were observed by CLSM. The osteogenic induction of Ti-PDOP-DNase I on MC3T3-E1 cells was investigated by ALP activity and RT-PCR. The adhesion clearance rate of viable bacteria on the surfaces of Ti-PDOP-DNase I was 91.95% for A.a, and 96.37% for F.n, and the 24 h biofilm formation of the bacteria was significantly inhibited. In addition, on DNase I coating, the mRNA level of osteogenic marker genes (alp, opn, bsp, sp7) and the activity of ALP were both up-regulated. Therefore, DNase I coating could be an alternative approach for preventing implant-related infection.

Diagnostic Accuracy of Oral Fluids Biomarker Profile to Determine the Current and Future Status of Periodontal and Peri-Implant Diseases

Severe periodontitis is ranked as the sixth most prevalent disease affecting humankind, with an estimated 740 million people affected worldwide. The diagnosis of periodontal diseases mainly relies upon assessment of conventional clinical parameters. However, these parameters reflect past, rather than current, clinical status or future disease progression and, likely, outcome of periodontal treatment. Specific and sensitive biomarkers for periodontal diseases have been examined widely to address these issues and some biomarkers have been translated as point-of-care (PoC) tests. The aim of this review was to provide an update on PoC tests for use in the diagnosis and management of periodontal diseases. Among the PoC tests developed so far, active matrix metalloproteinase-8 has shown promising results in terms of diagnostic and prognostic values. However, further studies are required to increase the sensitivity and specificity via combining more than one biomarker and merging these test kits with periodontal risk assessment tools. Furthermore, the validity of these test kits needs to be investigated by applying the results in further independent studies and the impact on these test kits', together with the results of risk factors for periodontal diseases, such as diabetes and smoking, also needs to be examined.

Obesity/Metabolic Syndrome and Diabetes Mellitus on Peri-implantitis

Literature has reported that up to 50% of dental implants may be affected by peri-implantitis, a bacteria-induced chronic inflammatory process, which promotes osteoclast-mediated bone resorption and inhibits bone formation, leading to progressive bone loss around implants. Current evidence points toward an increased risk for the development of peri-implantitis in both obesity/metabolic syndrome (MetS) and diabetes mellitus (DM) conditions relative to the healthy population. Currently, there is no effective treatment for peri-implantitis and the 50% prevalence in MetS and DM, along with its predicted increase in the worldwide population, presents a major concern in implant dentistry as hyperglycemic conditions are associated with bone-healing impairment; this may be through dysfunction of osteocalcin-induced glucose metabolism. The MetS/DM proinflammatory systemic condition and altered immune/microbiome response affect both catabolic and anabolic events of bone-healing that include increased osteoclastogenesis and compromised osteoblast activity, which could be explained by the dysfunction of insulin receptor that led to activation of signals related with osteoblast differentiation. Furthermore, chronic hyperglycemia along with associated micro- and macro-vascular ailments leads to delayed/impaired wound healing due to activation of pathways that are particularly important in initiating events linked to inflammation, oxidative stress, and cell apoptosis; this may be through deactivation of AKT/PKB protein, which possesses a pivotal role in drive survival and eNOS signaling. This review presents an overview of the local and systemic mechanisms synergistically affecting bone-healing impairment in MetS/DM individuals, as well as a rationale for hierarchical animal model selection, in an effort to characterize peri-implantitis disease and treatment.

Efficacy of a 0.03% chlorhexidine and 0.05% cetylpyridinium chloride mouth rinse in reducing inflammation around the teeth and implants: a randomized clinical trial

OBJECTIVES

To evaluate the efficacy of a 0.03% chlorhexidine (CHX) and 0.05% cetylpyridinium chloride (CPC) mouth rinse, as an adjunct to professional plaque removal (PPR) and mechanical hygiene, in the treatment of peri-implant mucositis (PiM) and gingivitis.

MATERIAL AND METHODS

Patients displaying PiM in, at least, one implant were included in this randomized, double-blinded, clinical trial. Subjects received PPR (at baseline and 6-month visits) and were instructed to rinse, twice daily, during 1 year with the tested mouth rinse or a placebo. Clinical and patient-reported outcomes were recorded at baseline and 6 and 12 months.

RESULTS

Fifty-four patients were included in the study and 46 attended the final visit. In the teeth and implants with inflammation, a higher reduction in BOP was observed in the test group. Statistically significant differences between groups were only observed in the lingual sites of the teeth with gingivitis (mean difference = 11.96%; 95% confidence interval [1.09; 22.83]; p = 0.03). Overall, compliance and satisfaction were good, even though staining were higher for the test group (p < 0.05).

CONCLUSIONS

The combined use of mechanical debridement with a 0.03% CHX and 0.05% CPC mouth rinse may have adjunctive benefits in the management of gingivitis, and it is associated with a higher degree of staining.

CLINICAL RELEVANCE

The control of gingivitis can be improved, after professional mechanical debridement, with toothbrushing and the supplementary use of a 0.03% CHX and 0.05% CPC mouth rinse at home.

CLINICAL TRIAL REGISTRATION NUMBER

NCT03533166.

Ultrastructural changes of smooth and rough titanium implant surfaces induced by metal and plastic periodontal probes

Objectives

To determine the ultrastructural changes of titanium surfaces of dental implants induced by the tip of periodontal probes.

Materials and methods

A total of 40 samples of smooth and rough surfaces of titanium implants were randomly assigned for the treatment with metal or plastic periodontal probes under application angles of 20° and 60°. Titanium surfaces have been evaluated with CLSM prior and following to experimental probing determining various standardized 2D and 3D roughness parameters.

Results

The average profile and surface roughness (Ra and Sa) showed no significant difference between treated and untreated samples on smooth and rough surface areas irrespective of the probe material. On smooth surfaces several amplitude roughness parameters were increased with metal probes but reached significance only for Rp (p = 0.007). Rough surface parts showed a slight but not significant reduction of roughness following to the contact with metal probes. The surface roughness remained almost unchanged on smooth and rough implant surfaces using plastic probes. The surface roughness on implant surfaces was not dependent on the application angle irrespective of the probe material.

Conclusion

Probing of titanium implants with metal probes and even less with plastic probes causes only minor changes of the surface roughness. The clinical significance of these changes remains to be elucidated.

Clinical relevance

Using plastic probes for the clinical evaluation of the peri-implant sulcus might avoid ultrastructural changes to titanium implant surfaces.

Clinical effects of the adjunctive use of a 0.03% chlorhexidine and 0.05% cetylpyridinium chloride mouth rinse in the management of peri-implant diseases: A randomized clinical trial

AIM

To evaluate the efficacy of a 0.03% chlorhexidine and 0.05% cetylpyridinium chloride mouth rinse, as an adjunct to professionally and patient-administered mechanical plaque removal, in the treatment of peri-implant mucositis (PiM).

MATERIAL AND METHODS

Patients displaying PiM in, at least, one implant were included in this randomized, double-blinded, clinical trial. Subjects received professional prophylaxis (baseline and 6 months) and were instructed to regular oral hygiene practices and to rinse, twice daily, with the test or placebo mouth rinses, during one year. Clinical, radiographic and microbiological outcomes were evaluated at baseline, 6 and 12 months. Disease resolution was defined as absence of bleeding on probing (BOP). Data were analysed by repeated measures ANOVA, Student's t and chi-square tests.

RESULTS

Fifty-four patients were included and 46 attended the final visit (22 in control and 24 in test group). In the test group, there was a 24.49% greater reduction in BOP at the buccal sites (95% confidence interval [3.65-45.34%]; p = 0.002) than in controls. About 58.3% of test implants and 50% controls showed healthy peri-implant tissues at final visit (p > 0.05).

CONCLUSIONS

The use of the test mouth rinse demonstrated some adjunctive benefits in the treatment of PiM. Complete disease resolution could not be achieved in every case.