Peri-implant disease, an important group of diseases that cause implant failure, are associated with metabolic abnormality. Metabolic syndrome (MetS) is a common metabolic disorder comprising abdominal obesity, hyperglycemia, systemic hypertension and atherogenic dyslipidemia. Previous studies had reported that MetS and its diversified clinical manifestations might be associated with peri-implant diseases, but the relationship and underlying mechanisms were unclear. This review aims to explore the relationship between MetS and peri-implant disease, in order to provide beneficial reference for the prevention and treatment of peri-implant disease in patients with MetS.
Humans ; Metabolic Syndrome/complications* ; Peri-Implantitis ; Dental Implants/adverse effects* ; Hypertension/complications* ; Risk Factors

OBJECTIVE: To compare the efficiency and effect of establishing rat peri-implantitis model by traditional cotton thread ligation and local injection of Porphyromonas gingivalis lipopolysaccharide (LPS) around the implant, as well as the combination of the two methods. METHODS: Left side maxillary first molars of 39 male SD rats were extracted, and titanium implants were implanted after four weeks of healing. After 4 weeks of implant osseointegration, 39 rats were randomly divided into 4 groups. Cotton thread ligation (n=12), local injection of LPS around the implant (n=12), and the two methods combined (n=12) were used to induce peri-implantitis, the rest 3 rats were untreated as control group. All procedures were conducted under 5% isoflurane inhalation anesthesia. The rats were sacrificed 2 weeks and 4 weeks after induction through carbon dioxide asphyxiation method. The maxilla of the rats in the test groups were collected and marginal bone loss was observed by micro-CT. The gingival tissues around the implants were collected for further real time quantitative PCR (RT-qPCR) analysis, specifically the expression of tumor necrosis factor-alpha (TNF-α) as well as interleukin-1β (IL-1β). The probing depth (PD), bleeding on probing (BOP) and gingival index (GI) of each rat in the experimental group were recorded before induction of inflammation and before death. RESULTS: After 4 weeks of implantation, the osseointegration of implants were confirmed. All the three test groups showed red and swollen gums, obvious marginal bone loss around implants. After 2 weeks and 4 weeks of inflammation induction, PD, GI and BOP of the three test groups increased compared with those before induction, but only BOP was statistically significant among the three test groups (P < 0.05). At the end of 2 weeks of inflammation induction, marginal bone loss was observed at each site in the cotton thread ligation group and the combined group. At each site, the bone resorption in the combined group was greater than that in the cotton thread ligation group, but the difference was not statistically significant (P > 0.05), bone resorption was observed at some sites of some implants in LPS local injection group. At the end of 4 weeks of inflammation induction, marginal bone loss was observed at all sites in each group. The marginal bone loss in the cotton thread ligation group and the combined group was greater than that in the LPS local injection group, and the difference was statistically significant (P < 0.05). At the end of 2 weeks and 4 weeks of induction, the expression of TNF-α and IL-1β in the test groups were higher than those in the control group (P < 0.05). CONCLUSION Compared with local injection of LPS around the implant, cotton thread ligature and the two methods combined can induce peri-implantitis in rats better and faster.
Animals ; Male ; Rats ; Alveolar Bone Loss/etiology* ; Dental Implants/adverse effects* ; Inflammation ; Lipopolysaccharides ; Peri-Implantitis/pathology* ; Rats, Sprague-Dawley ; Tumor Necrosis Factor-alpha

Peri-implantitis is one of the most important biological complications in the field of oral implantology. Identifying the causative factors of peri-implant inflammation and osteolysis is crucial for the disease's prevention and treatment. The underlying risk factors and detailed pathogenesis of peri-implantitis remain to be elucidated. Titanium-based implants as the most widely used implant inevitably release titanium particles into the surrounding tissue. Notably, the concentration of titanium particles increases significantly at peri-implantitis sites, suggesting titanium particles as a potential risk factor for the condition. Previous studies have indicated that titanium particles can induce peripheral osteolysis and foster the development of aseptic osteoarthritis in orthopedic joint replacement. However, it remains unconfirmed whether this phenomenon also triggers inflammation and bone resorption in peri-implant tissues. This review summarizes the distribution of titanium particles around the implant, the potential roles in peri-implantitis and the prevalent prevention strategies, which expects to provide new directions for the study of the pathogenesis and treatment of peri-implantitis.
Humans ; Peri-Implantitis/pathology* ; Titanium/pharmacology* ; Dental Implants/adverse effects* ; Osteolysis/pathology* ; Inflammation/chemically induced*

The failure rate of dental implantation in patients with well-controlled type 2 diabetes mellitus (T2DM) is higher than that in non-diabetic patients. This due, in part, to the impaired function of bone marrow mesenchymal stem cells (BMSCs) from the jawbone marrow of T2DM patients (DM-BMSCs), limiting implant osseointegration. RNA N6-methyladenine (m6A) is important for BMSC function and diabetes regulation. However, it remains unclear how to best regulate m6A modifications in DM-BMSCs to enhance function. Based on the "m6A site methylation stoichiometry" of m6A single nucleotide arrays, we identified 834 differential m6A-methylated genes in DM-BMSCs compared with normal-BMSCs (N-BMSCs), including 43 and 790 m6A hypermethylated and hypomethylated genes, respectively, and 1 gene containing hyper- and hypomethylated m6A sites. Differential m6A hypermethylated sites were primarily distributed in the coding sequence, while hypomethylated sites were mainly in the 3'-untranslated region. The largest and smallest proportions of m6A-methylated genes were on chromosome 1 and 21, respectively. MazF-PCR and real-time RT-PCR results for the validation of erythrocyte membrane protein band 4.1 like 3, activity-dependent neuroprotector homeobox (ADNP), growth differentiation factor 11 (GDF11), and regulator of G protein signalling 2 agree with m6A single nucleotide array results; ADNP and GDF11 mRNA expression decreased in DM-BMSCs. Furthermore, gene ontology and Kyoto Encyclopedia of Genes and Genomes analyses suggested that most of these genes were enriched in metabolic processes. This study reveals the differential m6A sites of DM-BMSCs compared with N-BMSCs and identifies candidate target genes to enhance BMSC function and improve implantation success in T2DM patients.
Humans ; Bone Marrow/metabolism* ; Bone Morphogenetic Proteins/metabolism* ; Dental Implants/adverse effects* ; Diabetes Mellitus, Type 2/metabolism* ; Growth Differentiation Factors/metabolism* ; Mesenchymal Stem Cells/metabolism* ; RNA/metabolism* ; RNA Processing, Post-Transcriptional

ABSTRACT Implant periapical lesion (IPL) is also known as retrograde peri-implantitis and as the name suggests, it involves inflammation surrounding the apical part of the dental implants. Previously, many studies have reported the event of IPL that further delays osseointegration, and some reported failure of implant placement due to this disease. In this article, we described two cases of early dental implant failure that was associated with active IPL and correlated the clinical and radiographical findings with the histopathological findings.
Dental Restoration Failure ; Dental Implants--adverse effects ; Periapical Tissue

The ideal axial orientation of implant is the key to the success of implant denture restoration. According to the restoration-oriented concept of implant, the implant axis direction should be consistent with the long axis direction of the suprastructure. In clinical practice, implant axial deviation leads to related complications, such as implant fracture, periimplant inflammation, and poor esthetic outcome of implant restoration, resulting in implant treatment failure. In this paper, complications related to improper implant axial orientation, their causes and treatment strategies are reviewed.
Dental Implants/adverse effects* ; Dental Prosthesis, Implant-Supported/adverse effects* ; Esthetics, Dental

Retrograde peri-implantitis (RPI), a kind of rare biological complication in implant-supported prosthetic rehabilitation, has been reported more frequently in recent years. RPI is defined as the periapical lesion that occurs following implant placement while the coronal part of the implant achieves normal osseointegration. Due to the possibilities of asymptomatic clinical scenarios, RPI can easily be ignored if routine radiographic examination is absent postoperatively, which may postpone treatment and affect long-term outcome. The common cause is infection originating from the periapical lesion of the neighboring teeth, the residual bacteria at the implant site, the contaminated implant apex and etc. Treatment methods rely on the infection source and severity of defect. This article discusses the diagnosis, classification, etiology, and pathology as well as prevention and treatment of RPI in order to provide evidence for clinical decisions in the future.
Dental Implantation, Endosseous ; Dental Implants/adverse effects* ; Humans ; Osseointegration ; Peri-Implantitis/prevention & control*

OBJECTIVETo compare the incidence of technical complications of implant-supported fixed dental prostheses in Chinese patients with a history of moderate or severe periodontitis and periodontally healthy patients(PHP) and analyze the effects of interproximal papillae patterns on food impaction and efficacy of plaque control.

METHODSA total of 103 partially edentulous patients treated with implant-supported fixed dental prostheses between December 2009 and December 2012 for a minimum 1-year follow-up period were recruited from Department of Periodontology, Peking University, School and Hospital of Stomatology. Based on the initial periodontal examination, the participants were divided into three groups: 30 PHP, 36 moderate periodontally compromised patients(mPCP) and 37 severe periodontally compromised patients(sPCP). Implant survival/loss, technical complications, plaque index, papilla index, food impaction and degree of proximal contact tightness of each patient were assessed around the implants at follow-up. According to the implant papilla index, the implants were divided into two groups: the "filling" group with the mesial and distal aspects with papilla index=3 and the "no filling" group with at least one aspect with papilla index<3. Data on implant survival, technical complications were analyzed. Comparisons of the incidence of technical complications were performed between the patients with different periodontal conditions with chi-square or Fisher's exact test. The influences of the interproximal papillae loss on food impaction and efficacy of plaque control were estimated with chi-square and Mann-Whitney U tests.

RESULTSThe total implant survival rate was 100%(162/162) for all three groups. Technical complications were as following: veneer fractures(1.9%, 3/162), abutment screw loosening(1.9%, 3/162), prosthetic screw loosening(3.1%, 5/162) and decementation(3.1%, 5/162) in all subjects. No implant/screw fracture was noted. The incidence of technical complications in sPCP, mPCP and PHP did not yield statistically significant differences(P>0.05). The proportion of the implant with the mesial and distal papilla index=3 in the sPCP was less than that in the PHP and mPCP. The interproximal papillae loss did not appear to affect the food impaction and the plaque index in all three groups(P>0.05). However, for the PHP, the accumulation of plaque at buccal aspect was more in the "no filling" group compared with the "filling" group (implant plaque index[M(Q)]: 1[1] vs 0[0]), and for the sPCP, the accumulation of plaque at lingual aspect was more in the "filling" group compared with the "no filling" group(implant plaque index[M(Q)]: 1[1] vs 0[1], (P<0.05).

CONCLUSIONSThe patients with a history of severe periodontitis did not exhibit more technical problems compared with the periodontally healthy patients. The interproximal papillae loss did not show a negative impact on the plaque control and food impaction. However, for the sPCP, changing the morphology and the position of the interproximal contact point to reduce the interdental black triangle may lead to accumulation of plaque at lingual aspect. More attention should be placed on the morphology design of prosthesis, but not the papillae filling up the interproximal space.

Beijing ; Dental Abutments ; Dental Implants ; Dental Plaque ; diagnosis ; etiology ; prevention & control ; Dental Plaque Index ; Dental Prosthesis, Implant-Supported ; adverse effects ; classification ; statistics & numerical data ; Dental Restoration Failure ; statistics & numerical data ; Follow-Up Studies ; Food ; Gingiva ; Humans ; Jaw, Edentulous, Partially ; rehabilitation ; Periodontal Diseases ; classification ; therapy

OBJECTIVETo clarify the related factors of marginal bone loss (MBL) around tissue level implants in the posterior part of the mandible.

METHODSA total of 116 tissue level implants were implanted in the mandibular posterior region of 76 patients. Patients' information, including general characteristics, implant characteristics, implant site characteristics, and prosthesis characteristics, was recorded. Their cone beam computed tomography data were measured immediately after implant placement, 3 months later, and 3 and 12 months after prosthesis loading. The measurement of MBL was conducted by One Volume Viewer software. SPSS 20.0 was used for statistic analysis.

RESULTSSmoking, cortical bone thickness (CBT), collum angle (CA), and implant local sanitation showed significant differences with body mass loss (P<0.05). No significant differences were found among sex, age, length of implant, diameter of implants, implant systems, bone height, prosthesis type, and MBL (P>0.05).

CONCLUSIONThe risk factors that caused MBL were smoking, thicker CBT, larger CA, and poor implant local sanitation. Among them, poor implant local sanitation had the highest correlation with MBL.

Alveolar Bone Loss ; epidemiology ; etiology ; Cone-Beam Computed Tomography ; Dental Implants ; adverse effects ; Dental Prosthesis Design ; Dental Prosthesis, Implant-Supported ; Follow-Up Studies ; Humans ; Mandible ; Mandibular Prosthesis ; statistics & numerical data ; Oral Hygiene ; Postoperative Complications ; Smoking ; adverse effects ; Treatment Outcome

Animals ; Dental Implantation, Endosseous ; adverse effects ; Dental Implants ; adverse effects ; Dental Prosthesis, Implant-Supported ; adverse effects ; Dentition ; Humans ; Malocclusion ; etiology ; Maxillofacial Development