Peri-implantitis is a pathologic condition associated with dental plaque that occurs in the implant tissue and is characterized by inflammation of the mucous membrane surrounding the implant, followed by the progressive loss of supporting bone. In this study, a case of guided bone regeneration therapy based on plaque control of peri-implant inflammation was reported. Four years after surgery for the left second premolar implant, the patient presented with "left lower posterior tooth swelling and discomfort for more than 2 years". The X-ray periapical film showed a decrease in distal bone mineral density of implant, and the clinical diagnosis was peri-implantitis of the left second premolar. Implants underwent guided bone regeneration and regular periodontal maintenance treatment. Re-examination at 3.5 months, 11 months, 18 months, and 7 years showed that the alveolar bone height and bone mineral density were stable, and the periodontal depth became shallow. However, the gingival recession was mild. In the present case, follow-up at 7 years demonstrated that the clinical periodontal indexes could be remarkably improved after complete periodontal treatment for peri-implantitis, and the alveolar bone could be well restored and regenerated.
Humans ; Peri-Implantitis/etiology* ; Follow-Up Studies ; Bone Regeneration ; Guided Tissue Regeneration, Periodontal/methods* ; Dental Plaque/prevention & control* ; Male ; Female ; Dental Implants/adverse effects*

Objective To explore the clinical efficacy and imaging changes of minimally invasive nonsurgical peri-odontal therapy(MINST)assisted by endoscopy for deep intrabony defects and to compare its effectiveness with that of traditional scaling and root planning(SRP)to therefore provide a reference for clinical periodontal treatment.Methods Patients with deep intrabony defects ≥ 4 mm in size were selected and divided into two groups:the MINST(MINST,20 cases,81 sites)group and the classic scaling and root planing(SRP,20 cases,80 sites)group.Before treatment and 12 and 24 months after treatment,probing depth(PD)and clinical attachment loss(CAL)were examined.Moreover,changes in the depth and angle of the intrabony defects were analyzed.Follow-up examination and maintenance treat-ment should be conducted every 3 months for 12 months after the initial treatment and every 6 months thereafter until 24 months.Results The PD and CAL of patients in both groups continued to decrease(P＜0.001),and imaging examinations revealed a decrease in defect depth and an increase in intrabony defect angle(P＜0.001).The changes in the first 12 months were significantly greater than those in the last 12 months in both groups(P＜0.001).The de-creases in PD,CAL,and depth of intrabony defects and increase in angle in the MINST group were significantly greater than those in the SRP group(P＜0.001).At 12 and 24 months after treatment,the PD and CAL in the MINST group were lower than those in the SRP group(P＜0.001).The defect height of the MINST group decreased more than that of the SRP group(P＜0.001),and the defect angle of the MINST group increased more than that of the SRP group(P＜0.001).Conclusion Minimally invasive nonsurgical periodontal therapy can significantly promote the healing of deep intrabony defects and the regeneration of alveolar bone.Imaging reflects that alveolar bone healing is rapid at first and then slows.Compared with traditional SRP,endoscopically assisted MINST can yield better clinical indicators and imag-ing changes in intrabony defects.

OBJECTIVES: To investigate the effect of oral microscope-assisted surface decontamination on implants in vitro. METHODS: Twelve implants that fell off because of severe peri-implantitis were collected, and decontamination was carried out on the surfaces of implants through curetting, ultrasound, titanium brushing, and sandblasting at 1×, 8×, or 12.8× magnifications. The number and sizes of residues on the implants' surfaces after decontamination were determined, and the decontamination effect was analyzed according to the thread spacing in the different parts of the thread. RESULTS: 1) The 8× and 12.8× groups scored lower for implant surface residues than the 1× group (P<0.000 1), and the 12.8× group scored lower than the 8× group (P<0.001); 2) no difference in residue score was found between the wide and narrow thread pitch (P>0.05), and the 8× and 12.8× groups had lower scores than the 1× group (P<0.001); 3) the lowest number of contaminants was observed at the tip of the thread, whereas the highest was observed below the thread, and the difference was significant (P<0.001). However, the thread pitch had no effect on the number of contaminants in different areas (P>0.05); 4) the residue scores of the 8× and 12.8× groups were lower than those of the 1× group at the thread tip and above, sag, and below the thread of the implants (P<0.05). CONCLUSIONS Residues on the surfaces of contaminated implants can be effectively removed by using an oral microscope. After decontamination, the residues of pollutants were mainly concentrated below the thread of the implants, and the thread pitch of the implants had no significant effect on the residues.
Humans ; Dental Implants ; Decontamination ; Surface Properties ; Peri-Implantitis ; Titanium

Objective : To investigate the clinical effect of periodontal endoscope-assisted scaling and root planing (SRP) in treating advanced periodontitis. Methods: Nineteen cases of grade Ⅲ and Ⅳ periodontitis selected from June 2017 to January 2019 in the Nanjing Stomatological Hospital, Medical School of Nanjing University were divided into the periodontal endoscope and control groups. In the periodontal endoscope group, SRP was performed under a periodontal microscope in one treatment after initial supragingival scaling; in the control group, SRP was performed under regular conditions, and additional SRP was conducted in positive bleeding on probing sites twice every other week as needed. Periodontal status, including probing depth (PD), bleeding on probing (BOP) and attachment loss (AL), was recorded by a Florida probe. Results: For sites of 40.05). There was no significant difference in the BOP positive rate or AL change between the two groups at 3 months and 6 months (P > 0.05). For sites with PD > 6 mm, at baseline, the positive rates of PD, BOP and AL in the endoscope group were more serious than those in the control group, and the differences were statistically significant. The PD- and BOP-positive rates and AL in the endoscope group and control group decreased significantly from baseline at 3 and 6 months. However, PD in the endoscope group became shallower than that in the control group (P < 0.05) after 3 and 6 months. There was no significant difference in the BOP positive rate or AL between the two groups (P>0.05). Conclusion When compared to regular SRP, periodontal microscope-assisted SRP achieves better improvement in PD and is more beneficial for reducing the BOP and AL of deeper sites.

Objective: To analyze the immune responses of bone-marrow derived macrophages and osteoclasts to lipopolysaccharide from Porphyromonas gingivalis (Pg-LPS) so as to provide reference for host immunomodulatory therapy of periodontitis. Methods: Bone marrow mononuclear cells from C57BL/6 mice were obtained and induced into bone marrow macrophages (BMM) and osteoclasts (OC) by conditioned medium. The BMMs and OCs were divided into blank control group and Pg-LPS treated experimental group. Pg-LPS (10 μg/ml) was used to stimulate BMM and OC. The mRNA and protein expression of TLR-2 and TLR-4 and secretion of inflammatory cytokines were detected, respectively. Furthermore, the effect of Pg-LPS on the differentiation of BMM into OC was evaluated. Results: Mouse bone marrow mononuclear cells were successfully induced into BMM and mature OC. In the presence of Pg-LPS, the gene level of TLR-2 in BMM was significantly up-regulated by (41.41±13.07) folds (P<0.01), while the level of TLR-4 mRNA was not significantly changed. TLR-2 mRNA and TLR-4 mRNA levels in OC increased by (2.24±0.23) times (P<0.05) and (4.83±1.07) times (P<0.01), respectively. Flow cytometry results showed that TLR-2 protein expression in BMM was robustly enhanced (P<0.01), as mean fluorescence intensities (MFI) were (39.85±5.27) in blank group and (221.57±13.13) in experimental group, respectively. The MFI of TLR-2 in OC also increased as (83.31±2.69) in blank group and (108.65±6.32) in experimental group, respectively (P<0.01). However, no significant TLR-4 expressions were observed in both BMM and OC (P>0.05). Moreover, the productions of tumor necrosis factor-α and interleukin-6 in response to LPS in BMM and OC remarkably increased (P<0.01). Lower cytokine expression was observed in OC than that in BMM (P<0.01). In addition, Pg-LPS obviously inhibited the number and size of OC formation, with a reduction in area percentage of approximately 47%. Conclusions Pg-LPS generated a robust immune inflammatory response to BMM, while OC had a relatively weaker immune response to the Pg-LPS. Pg-LPS might inhibite the differentiation of BMM into OC.