Objective:To evaluate the factors associated with the gingival papilla deficiencies of different degrees between maxillary anterior teeth showing alveolar ridge absorption.Methods:A total of 64 gingival papillae between maxillary anterior teeth of 14 patients with periodontitis, who received periodontal treatment and regular review in the Department of Periodontology, Peking University School and Hospital of Stomatology from June 2019 to December 2019, were observed in the present study. Indices were measured by using standardized clinical photographs and cone-beam CT images. The correlations between the gingival papilla deficiencies of different degrees and the distance from contact point to bone crest (CP-BC), the distance from proximal cemento-enamel junction to bone crest (pCEJ-BC), interproximal distance between roots (RD), the width of bone crest (BCW) and the height of gingival papilla (PH) were evaluated. Statistical analyses such as t-test, ANOVA, Pearson correlation coefficient and so on were conducted. Results:The rate of maxillary anterior gingival papilla completely filled the adjacent spaces between anterior teeth was 28% (18/64) and the rate of gingival papilla with deficiencies was 72% (46/64). The mild, moderate and severe deficiencies were 36% (23/64), 27% (17/64) and 9% (6/64) respectively. When CP-BC≥7.0 mm or pCEJ-BC≥4.5 mm, only moderate or severe deficiencies appeared. However, when CP-BC<5.0 mm or pCEJ-BC<1.5 mm, only completely filled adjacent tooth space or mild deficiency appeared. There was a strong positive correlation between CP-BC and pCEJ-BC. The Pearson correlation coefficient was 0.812 ( P<0.01), and the linear fitting coefficient was 0.93 ( R2=0.659) (64 gingival papillae). There was no significant difference of RD for gingival papilla deficiencies of different degrees between maxillary anterior teeth ( P>0.05). BCW at the crest level increased slightly with the increase of the degree of gingival papilla deficiency, and the difference was statistically significant between completely filled adjacent tooth space and moderate or severe deficiency ( P<0.05). However, PH at the crest level decreased slightly with the increase of the degree of gingival papilla deficiency, and the difference was statistically significant between completely filled adjacent tooth space and moderate or severe deficiency ( P<0.05). Conclusions:When the alveolar ridge is absorbed, the rate of deficiency is significantly higher than the completely filled adjacent tooth space. The gingival papilla deficiencies of different degrees between maxillary anterior teeth are mainly associated with the absorption of bone crest.

Gingival papilla deficiency may cause dental plaque stagnation and food impaction, and may also affect the appearance and pronunciation when occurs in the upper anterior teeth. It has become a common concern of patients and doctors. The aetiological factors of gingival papilla deficiency were complex. Various surgical or non-surgical treatments have been reported. This paper reviews and analyzes the current research progress on the factors and treatment methods of gingival papilla deficiency in domestic and foreign studies, summarizes the factors associated with the gingival papilla deficiency and summarizes the corresponding treatment strategy, so as to provide reference for clinical and research works.

Periodontitis is a widespread oral disease characterized by continuous inflammation of the periodontal tissue and an irreversible alveolar bone loss, which eventually leads to tooth loss. Four-octyl itaconate (4-OI) is a cell-permeable itaconate derivative and has been recognized as a promising therapeutic target for the treatment of inflammatory diseases. Here, we explored, for the first time, the protective effect of 4-OI on inhibiting periodontal destruction, ameliorating local inflammation, and the underlying mechanism in periodontitis. Here we showed that 4-OI treatment ameliorates inflammation induced by lipopolysaccharide in the periodontal microenvironment. 4-OI can also significantly alleviate inflammation and alveolar bone loss via Nrf2 activation as observed on samples from experimental periodontitis in the C57BL/6 mice. This was further confirmed as silencing Nrf2 blocked the antioxidant effect of 4-OI by downregulating the expression of downstream antioxidant enzymes. Additionally, molecular docking simulation indicated the possible mechanism under Nrf2 activation. Also, in Nrf2^-/- mice, 4-OI treatment did not protect against alveolar bone dysfunction due to induced periodontitis, which underlined the importance of the Nrf2 in 4-OI mediated periodontitis treatment. Our results indicated that 4-OI attenuates inflammation and oxidative stress via disassociation of KEAP1-Nrf2 and activation of Nrf2 signaling cascade. Taken together, local administration of 4-OI offers clinical potential to inhibit periodontal destruction, ameliorate local inflammation for more predictable periodontitis.
Alveolar Bone Loss/prevention & control* ; Animals ; Antioxidants/pharmacology* ; Inflammation ; Kelch-Like ECH-Associated Protein 1/metabolism* ; Mice ; Mice, Inbred C57BL ; Molecular Docking Simulation ; NF-E2-Related Factor 2/metabolism* ; Periodontitis/prevention & control* ; Succinates

Periodontitis is the most widespread oral disease and is closely related to the oral microbiota. The oral microbiota is adversely affected by some pharmacologic treatments. Systemic antibiotics are widely used for infectious diseases but can lead to gut dysbiosis, causing negative effects on the human body. Whether systemic antibiotic-induced gut dysbiosis can affect the oral microbiota or even periodontitis has not yet been addressed. In this research, mice were exposed to drinking water containing a cocktail of four antibiotics to explore how systemic antibiotics affect microbiota pathogenicity and oral bone loss. The results demonstrated, for the first time, that gut dysbiosis caused by long-term use of antibiotics can disturb the oral microbiota and aggravate periodontitis. Moreover, the expression of cytokines related to Th17 was increased while transcription factors and cytokines related to Treg were decreased in the periodontal tissue. Fecal microbiota transplantation with normal mice feces restored the gut microbiota and barrier, decreased the pathogenicity of the oral microbiota, reversed the Th17/Treg imbalance in periodontal tissue, and alleviated alveolar bone loss. This study highlights the potential adverse effects of long-term systemic antibiotics-induced gut dysbiosis on the oral microbiota and periodontitis. A Th17/Treg imbalance might be related to this relationship. Importantly, these results reveal that the periodontal condition of patients should be assessed regularly when using systemic antibiotics in clinical practice.
Humans ; Mice ; Animals ; Dysbiosis ; Anti-Bacterial Agents/pharmacology* ; Virulence ; Microbiota ; Periodontitis/chemically induced* ; Cytokines