[Healing effect of photodynamic therapy on extraction sockets of periodontally compromised teeth: a randomized, controlled, superiority clinical trial].

Objective: To evaluate the effects of photodynamic therapy (PDT) in extraction sockets of periodontally compromised molars on soft tissue healing, postoperative pain, bone density and bone height changes. Methods: This study is a single-center, single-blind, randomized controlled superiority clinical trial. Thirty-eight periodontally compromised molars requiring extraction in patients attending the Department of Periodontology, Stomatology Hospital, School of Stomatology, Zhejiang University School of Medicine, from December 2022 to September 2023 were included, and randomly assigned to PDT group and control group. The control group received routine debridement after extraction, while PDT group received routine debridement followed by PDT. The bucco-lingual and mesio-distal wound distances at 7 and 14 d after extraction were measured, and then the wound closure rates were calculated. Evaluating the soft tissue healing indexes at 7 and 14 d after extraction. The visual analogue scale was used to assess the pain level at 6 h, 1 d, 2 d, and 3 d after tooth extraction. Apical radiographs were taken immediately and 2 months after extraction in order to compare the changes of the bone density and height. Results: The wound closure rate at 1 week was (78.08±5.45)% in PDT group and (71.03±6.82)% in control group, with significant differences (P<0.01). The wound closure rate at 2 weeks in PDT group [(85.88±3.84) %] was significantly higher than that in the control group [(81.66±3.79) %] (P<0.01), but did not reach the superiority value of the superiority test (superiority value=10%, 95%CI at 1 week: 3.00%-11.12%, 95%CI at 2 weeks: 1.71%-6.73%). The soft tissue healing index of PDT group at 1 week was significantly better than the control group (P<0.05), but there was no significant difference between the two groups at 2 weeks (P>0.05). There was no significant difference between the two groups in terms of postoperative pain at 6 h, 1 d, 2 d and 3 d as well as in bone density and height changes at 2 months after tooth extraction (P>0.05). Conclusions: PDT could promote soft tissues healing to some extent, but did not provide additional assistance in the healing of extraction sockets of periodontally compromised teeth. PDT did not show benefits on postoperative pain, changes of the bone density and bone height after tooth extraction.

Casp11 Deficiency Alters Subgingival Microbiota and Attenuates Periodontitis.

Periodontitis (PD) is the primary cause of tooth loss in adults. Porphyromonas gingivalis (P.g), a keystone pathogen, has been identified as a crucial contributor to this process. Pyroptosis activation in PD is acknowledged, with accumulating evidence underscoring the crucial role of Caspase-11 (described as Caspase-4/5 in humans)-mediated noncanonical pyroptosis. However, the mechanism behind its impact on PD remains unclear. In this study, we delved into the interplay between the Caspase-11-mediated noncanonical pyroptosis, subgingival microbiota alteration, and macrophage polarization. Clinical samples from PD patients revealed heightened expression of Caspase-4, gasdermin-D, and their active fragments, pointing to the activation of the noncanonical pyroptosis. Single-cell sequencing analysis linked Caspase-4 with gingival macrophages, emphasizing their involvement in PD. In vitro cell experiments confirmed that P.g-induced pyroptosis was activated in macrophages, with Casp11 deficiency attenuating these effects. In an experimental PD mouse model, Casp11 deficiency led to an alteration in subgingival microbiota composition and reduced alveolar bone resorption. Casp11-/- mice cohousing with wild-type mice confirmed the alteration of the subgingival microbiota and aggravated the alveolar bone resorption. Notably, Casp11 deficiency led to decreased M1-polarized macrophages, corresponding with reduced alveolar bone resorption, uncovering a connection between subgingival microbiota alteration, macrophage M1 polarization, and alveolar bone resorption. Taken together, we showed that Caspase-11 fulfilled a crucial role in the noncanonical pyroptosis in PD, potentially influencing the subgingival microbiota and linking to M1 polarization, which was associated with alveolar bone resorption. These findings underscored the pivotal role of the Caspase-11-mediated noncanonical pyroptosis in PD pathogenesis and may provide critical insights into potential therapeutic avenues for mitigating PD.

[Standardized nomenclature of oral microorganisms in Chinese: the 2023 update].

Oral microbial community, as an important part of human microbial community, is closely related to oral and general health. Oral microbiological research has become the forefront of international microbiological research. Standardized and unified nomenclature for oral microorganisms in Chinese is of great significance to support the development of oral medicine research. Standardized translation of microbial names is the basis for writing canonical and authoritative professional textbooks and reference books, which helps students to accurately acquire the characteristics and classifications of oral microbes. Unified translation of oral microorganisms is also conducive to academic communication and cooperation, and plays an important role in oral health education and science popularization, which enables oral microbiology knowledge to be accurately disseminated to the public. Therefore, in order to standardize the words in scientific research, funding application, publications, academic exchanges and science popularization within the field of oral medicine, we have fully discussed and revised the Chinese names of oral microorganisms in 2017 edition and ones of newly discovered oral microbes, finally reaching a consensus to form the 2023 edition of Chinese names of oral microorganisms.

[Advances in research of pyroptosis in the mechanism of periodontal disease].

Pyroptosis is a pro-inflammatory form of programmed cell death that has been gradually recognized in recent years. It plays an important role in recognizing the invasion of exogenous pathogens and sensing endogenous danger signals. The initiation of pyroptosis depends on the activation of intracellular inflammasome and its downstream caspases, as well as the active fragment of the key protein Gasdermin. The invasion of periodontal pathogens induces an inflammatory response of the host, involving the activation of inflammasome and triggering pyroptosis as well. Meanwhile, it leads to the release of a large number of inflammatory cytokines such as interleukin (IL)-1ß and IL-18 to amplify the inflammatory response and mediate periodontal tissue destruction eventually. This article reviews the research progress of the signaling pathways of pyroptosis, as well as its mechanism induced by periodontal pathogens and the mechanism of periodontal tissue damage in periodontitis in order to provide new targets and ideas for the prevention and treatment of periodontitis.

[Keratinized tissue augmentation techniques around dental implants].

Research have indicated that inadequate keratinized tissue has a negative effect on patient oral hygiene, resulting in peri-implant inflammation. It has been recommended that an apically repositioned flap alone or in combination with autogenous soft tissue grafts can increase the width of keratinized mucosa around dental implants, which promotes long term peri-implant health. This review summarized research progress on augmentation techniques of keratinized tissue arround implants in recent years, so as to provide reference for clinical practice and research design in the future.

[Long-term stability of periodontal root coverage procedures for gingival recession].

Gingival recession could result in root exposure, dental hypersensitivity and poor aesthetics. It has been demonstrated that varieties of root coverage procedures can significantly improve gingival recession in short-term (≤6 months), of which coronally advanced flap combined with connective tissue graft is the gold standard technique for treatment of gingival recession. It could obtain the optimally complete root coverage and maintain long-term stability (≥2 years). However, clinical knowledge about the long-term effectiveness of the other alternative graft materials remain very limited. Based on the existing clinical evidence, this article reviews coronally advanced flap, coronally advanced flap combined with connective tissue graft or alternative graft materials, with particular attention to the long-term stability of them, in order to provide reference for the design of further clinical trials and the plan of clinical treatments.

The role of lipopolysaccharide-binding protein in innate immunity: a revisit and its relevance to oral/periodontal health.

Lipopolysaccharide (LPS)-binding protein (LBP) functions as an acute phase protein and plays a key role in the innate immune response to bacterial challenge. It is a potential acute-phase biomarker in monitoring the progress of severe sepsis, infectious endocarditis and cardiovascular disease. LBP is mainly synthesized in hepatocytes and generates binding of bacteria and/or their products such as LPS to cell surface receptors, thereby initiating an innate host response. Interestingly, LBP has a dual role depending on its relatively low or high concentrations, and augments or downregulates the innate host defense accordingly. Emerging evidence indicates that LBP can be produced by non-hepatocytes, including respiratory type II epithelial cells, intestinal epithelial cells and human gingival epithelia. These findings suggest that LBP formation at extrahepatic cells may be crucial in containing microbial in situ challenge constantly, critically contributing to tissue homeostasis. This review provides an update on the characteristics and novel functions of LBP as well as its gene polymorphisms and potential use as a biomarker in assessing common infectious and inflammatory diseases such as periodontal disease. This paper highlights the expression profiles of LBP in human oral/gingival cells, how its expression could be modulated by periodontopathogens such as Porphyromonas gingivalis, as well as the relevant regulation mechanisms and signaling pathways involved. The critical roles of LBP in periodontal homeostasis and perspectives for its clinical application are discussed.

Nuclear factor-κB and p38 mitogen-activated protein kinase signaling pathways are critically involved in Porphyromonas gingivalis lipopolysaccharide induction of lipopolysaccharide-binding protein expression in human oral keratinocytes.

Lipopolysaccharide (LPS) -binding protein (LBP) plays a crucial role in innate host response to bacterial challenge. Porphyromonas gingivalis is a keystone pathogen in periodontal disease and the shift of P. gingivalis LPS lipid A structure from penta-acylated (LPS(1690)) to tetra-acylated (LPS(1435/1449)) isoform may significantly contribute to periodontal pathogenesis. We recently demonstrated that LBP is expressed in human gingiva and contributes to periodontal homeostasis. Furthermore, different isoforms of P. gingivalis LPS differently modulate the immuno-inflammatory response, and P. gingivalis LPS(1690) induces LBP expression in human oral keratinocytes (HOKs). This study further examined the signaling mechanisms of P. gingivalis LPS(1690) -induced and Escherichia coli LPS-induced LBP expression in HOKs. Both P. gingivalis LPS(1690) and E. coli LPS were potent inducers of LBP expression in HOKs. The former activated phosphorylation of IκBα, p65, p38 mitogen-activated protein kinase (MAPK) and stress-activated protein kinase/c-Jun N-terminal kinase (SAPK/JNK), whereas the latter phosphorylated IκBα, p38 MAPK and SAPK/JNK. A nuclear translocation of NF-κB transcription factor was confirmed upon stimulation by both forms of LPS. Further blocking assay showed that P. gingivalis LPS(1690) induction of LBP was through NF-κB and p38 MPAK pathways, whereas E. coli LPS-induced LBP expression was mediated by NF-κB, p38 MPAK and JNK pathways. This study demonstrates that NF-κB and p38 MAPK signaling pathways are involved in P. gingivalis LPS(1690) induction of LBP expression in HOKs. The current findings could enhance the understanding of the molecular mechanisms of innate defense in maintenance of periodontal homeostasis.

Pegylated interferon alfa-2b (peg-intron) plus ribavirin (rebetol) in the treatment of chronic hepatitis C: a local experience.

This was an open-label, uncontrolled study with the aim of assessing the efficacy and safety of pegylated interferon alfa-2b plus ribavirin in the treatment of chronic hepatitis C. The study was conducted in Island Hospital, Penang beween January 2002 and December 2003. Thirty-three patients were enrolled in this study with ten defaulters. The overall sustained virological response (SVR) (Intention-To-Treat analysis) in naïve patients was 39.10%. However, when the study was adjusted to only include those who completed treatment and follow-up, overall SVR as 52.9%. Side-effects were tolerable in most patients with anaemia occurring in 22 patients (66.7%), leukopenia 23 patients (69.7%) and thrombocytopenia in 15 patients (45.5%). This study showed that pegylated interferon alfa-2b 1.5 mcg/kg/week plus ribavirin > 10.6 mg/kg/day is efficacious and safe to be used in the treatment of: chronic hepatitis C.

Endoscopic pneumatic balloon dilatation for achalasia of the cardia.

This study evaluated the efficacy and safety of endoscopic pneumatic balloon dilatation as the initial treatment for achalasia of the cardia. 15 patients with achalasia underwent a total of 19 dilatations using the new polyethylene dilator (Microvasive Rigiflex Balloon Dilator) over the last 6 years. An overall treatment success rate of 93% was achieved. 11 patients (73.3%) have not required a further dilatation and 3 patients (20%) required between 1 and 2 further dilatations. Elective surgery was necessary in 1 patient. The mean follow-up period was 31.5 months. There was no complication or death attributable to the procedure. Endoscopic pneumatic balloon dilation is a safe and effective treatment for achalasia and should be considered as the initial treatment of choice in most patients with achalasia.

The role of abdominal angiography in difficult gastrointestinal bleeding.

Two cases of leiomyomas of the jejunum presenting with gastrointestinal bleeding of uncertain origin are described. Diagnosis was finally established by selective angiography. Laparotomy and resection of the tumour were successfully performed. The approach and management of this rare tumour are outlined.