Life satisfaction and peace of mind among dentists: a cross-sectional study.

OBJECTIVES: This study sought to identify the factors associated with the life satisfaction and peace of mind (PoM) of dentists not in full-time clinical training. MATERIALS AND METHODS: Cross-sectional questionnaires were distributed to dentists in Taiwan to collect their life satisfaction, PoM, sociodemographic data, and dental career-related characteristics. Life satisfaction was measured using a 5-item Satisfaction with Life Scale. PoM was measured using a 7-item Peace of Mind Scale. Descriptive statistics and multiple linear regression models were estimated to explore potential associations between the two scales and the examined factors. RESULTS: A total of 1196 dentists (45.6% female; mean age = 44.12) completed the questionnaires. The response rate of completed questionnaires from email invitations was 32.9%. On multivariable analysis, life satisfaction and PoM were associated with age (b = 0.008 in both), better perceived health (b = 0.262 and 0.308, respectively), family interaction (b = 0.264 and 0.207, respectively), and friend relationships (b = 0.076 and 0.091, respectively). Being married (b = 0.191), being specialized (b = 0.127), working in private practice, and spending 10 to 39 h per week with patients (b = 0.101 to 0.162) were associated with a higher level of life satisfaction but not PoM. CONCLUSIONS: Specialists working in private practice without working overtime were associated with better life satisfaction. However, the dentists' health and relationships with family were more related to their subjective well-being than their professional achievements. CLINICAL RELEVANCE: Our findings can help policymakers increase awareness of the well-being of general dentists and those in academia or hospitals to promote their mental health.

Life Satisfaction of US-trained Dental Specialists in Taiwan.

OBJECTIVE: A large number of residents in US advanced specialty education programmes are foreign-trained dentists. When faced with the career dilemma of applying for US residency training, foreign-trained dentists may wonder whether it is worth proceeding along that path. In addiditon, studies capturing benefits from receiving US residency training are rare. Therefore, this study compared the life satisfaction amongst 3 dentist groups in Taiwan (ie, US-trained specialists, Taiwan-trained specialists, and general dentists). METHODS: Cross-sectional surveys were distributed to dentists currently residing in Taiwan. Participants were surveyed about demographic information, career-related information, and life satisfaction. Life satisfaction was measured with a structured Satisfaction With Life Scale (SWLS). Nonparametric bivariate analyses and multivariable adjusted generalised linear model (GLM) were used to examine the differences between mean SWLS scores and examined variables. We included 134 US-trained specialists, 134 Taiwan-trained specialists, and 134 general dentists matched for age, sex, and marital status. RESULTS: With the mean age of 51.4 ± 10.8 years old, specialists had significantly higher mean life satisfaction scores than general dentists. US-trained specialists had significantly higher mean life satisfaction scores than Taiwan-trained specialists when health and family relationships were not considered. Career-rated factors (eg, spending more clinical hours with patients, having more expenses related to continuing education, publishing more peer-reviewed articles, and being a frequent speaker) were not associated with better life satisfaction. CONCLUSIONS: US-trained specialists were more likely to be satisfied with their lives than Taiwan-trained specialists and general dentists. However, health and social relationships contribute more to dentists' life satisfaction than do career-rated factors.

Is periodontitis a risk factor of benign or malignant colorectal tumor? A population-based cohort study.

OBJECTIVE: To examine the risk of developing benign or malignant colorectal tumors in patients with periodontitis within 15 years using Taiwan's National Health Insurance Database. BACKGROUND: Studies have shown that colorectal carcinoma often develops under inflammatory conditions and changes of microbiota in the gut. Recently, a link between Fusobacterium nucleatum, a periodontal pathogen, and colorectal carcinoma has been proposed. However, whether periodontitis is a risk of developing colorectal tumor remains uncertain. METHODS: In total, 35 124 participants were enrolled from 2000 to 2015 to examine the development risk of benign colorectal tumors, including 11 708 patients with periodontitis who received therapy (group 1), 11 708 patients with periodontitis not receiving periodontal treatment (group 2), and 11 708 non-periodontitis controls after matching for gender, age, and index year. To examine the risk of developing colorectal malignancy, 11 720 participants were assigned to each of the three groups. Cox proportional hazards model and Kaplan-Meier methods were used to compare the risks. Sensitivity analysis was performed, excluding the diagnoses during the first 1 or 5 years. RESULTS: After the follow-up, 177, 154, and 63 participants in group 1, group 2, and control group had benign colorectal tumors. Patients with periodontitis tended to be associated with a greater rate of having a benign colorectal tumor. The adjusted hazard ratios (aHRs) were 3.77 (95% confidence interval [CI] 2.01-4.82, p < .001) and 2.85 (95% CI 1.62-3.74, p < .001) for groups 1 and 2, respectively. Regarding the risk of malignant colorectal tumor, 20, 18, and 14 participants who developed malignant tumors were included in group 1, group 2, and control group; however, no significant increase in malignancy was observed in periodontitis groups (aHR1.92, 95% CI 0.74-2.36, p = .482; aHR 1.50, 95% CI 0.68-1.97, p = .529, for the two periodontitis groups, respectively). CONCLUSIONS: The results of this study suggest that patients with periodontitis may have an increased risk of developing benign, but not malignant, colorectal tumors.

Bone formation with functionalized 3D printed poly-ε-caprolactone scaffold with plasma-rich-fibrin implanted in critical-sized calvaria defect of rat.

BACKGROUND/PURPOSE: Space-making is one of the essential factors for bone regeneration in severe bony defect. To test the hypothesis that an appropriately designed scaffold may be beneficial for the bone formation in defect, the new bone formed in the critical-size calvarial defect of rat was examined after implanted with a 3D-printed poly-ɛ-caprolactone (PCL) scaffold, retaining with and without plasma rich fibrin (PRF). MATERIALS AND METHODS: Thirty-two rats were divided into four groups (control, PCL, PRF, and PCL-plus-PRF). A custom-made 3D-printed PCL scaffold, 900 µm in pore size, retaining with and without PRF, was implanted into a critical-sized calvarial defect, 6 mm in diameter. Animals were sacrificed at week-4 or 8 after implantation for assessing the new bone formation by dental radiography, micro-computed tomography (µ-CT), and histology. RESULTS: By radiography and µ-CT, significantly greater mineralization areas/volumes were observed in defects with 3D-printed scaffold groups compared to that without the scaffold in both two-time points. However, no advantage was found by adding PRF. Histology showed that bone tissues grew into the central zone of the critical defect when 3D-printed PCL scaffold was present. In contrast, for the groups without the scaffolds, new bones were formed mostly along defect borders, and the central zones of the defects were collapsed and healed with thin connective tissue. CONCLUSION: Our results suggest that the use of a 900 µm pore size 3D-printed PCL scaffold may have the potential in facilitating the new bone formation.

Life satisfaction of Taiwanese dental graduates received residencies in the U.S.: a cross-sectional study.

BACKGROUND: Each year, more than 200 international dental graduates start U.S. specialty trainings to become specialists. It is unknown if their life satisfaction is associated with any dental career-related factor before residencies (e.g. dental school class rank, research experience, or private practice experience) and after residencies (e.g. staying in the U.S., teaching status, workplace, or board certification). This cross-sectional study aimed to identify these potential factors by surveying Taiwanese dental graduates who pursued U.S. residencies. METHODS: Life satisfaction was measured with a structured questionnaire, Satisfaction With Life Scale (SWLS), which includes five statements on a 5-point Likert scale. Online surveys were sent out to 290 Taiwanese dental graduates who were known to pursue U.S. residencies. T-test, one way analysis of variance, and multivariable adjusted generalized linear model (GLM) were used to assess the differences of mean SWLS scores from different variables. RESULTS: Surveys were completed by 158 dentists. Mean SWLS score of 125 specialists was higher (p = 0.0007) than the score of 33 residents. For the 125 specialists, multivariable adjusted GLM demonstrated better life satisfaction was positively associated with multiple independent factors, such as having research experience, being ranked in the top 26 ~ 50% of the class in dental school, starting U.S. residency within 4 years after dental school, starting residency before year 1996, and specializing in endodontics (vs. periodontics). Life satisfaction was not associated with any factors after residency (e.g. staying in the U.S. afterwards, teaching status, or workplace), but better mean life satisfaction score was significantly associated with being American specialty board certified (p < 0.001) for the specialists in the 26 ~ 75% of their class in dental school. For the 33 residents, better mean life satisfaction score was associated with better dental school class rank in both bivariate (p = 0.020) and multivariable adjusted GLM (p = 0.004) analyses. CONCLUSIONS: The life satisfaction of Taiwanese dental graduates pursuing U.S. residencies might be associated with some professional factors, such as research experience, dental school class rank, residency timing, specialty type, and specialty board certification. We hope our results may provide some objective information on making career decisions for international dental graduates/students who are preparing for U.S. residency.

CD147 self-regulates matrix metalloproteinase-2 release in gingival fibroblasts after coculturing with U937 monocytic cells.

BACKGROUND: Cluster of differentiation 147 (CD147) is a multifunctional glycoprotein that functions as an inducer of matrix metalloproteinase (MMP) expression in fibroblasts. Synergistically enhanced MMP-2 expression was recently observed in the coculture of human gingival fibroblasts (HGFs) and U937 human monocytic cells; however, the responsible mechanisms have not yet been fully established. The aim of this study was to evaluate the release of soluble CD147 in HGFs after coculturing with U937 cells and its functional effect on the enhancement of MMP-2 expression in HGFs. METHODS: Enzyme-linked immunosorbent assay was used to determine the amount of CD147 protein in media, whereas real-time polymerase chain reaction was performed to evaluate the mRNA levels of CD147 and MMP-2 in HGFs and U937 cells. The enzyme activities of MMP-2 released from cells were examined by zymography. Transwell coculturing and conditioned media treatments were selected to rule out the effect of direct contact of HGFs and U937 cells. RESULTS: The protein and mRNA expression of CD147 in HGFs were enhanced after transwell coculturing with U937 cells and exposure to U937-conditioned medium. MMP-2 enzyme activities in HGFs were also significantly increased by the coculturing methods. Administration of exogenous CD147 enhanced MMP-2 expression in HGFs, whereas treatment with cyclosporine-A, which inhibited CD147 expression, reduced U937-enhanced MMP-2 expression in HGFs. CONCLUSIONS: CD147 can interact with fibroblasts to stimulate the expression of MMPs associated with periodontal extracellular matrix degradation. This study has demonstrated that CD147 released from fibroblasts might play a role in monocyte-enhanced MMP-2 expression in HGFs.

Zfp423 Regulates Skeletal Muscle Regeneration and Proliferation.

Satellite cells (SCs) are skeletal muscle stem cells that proliferate in response to injury and provide myogenic precursors for growth and repair. Zfp423 is a transcriptional cofactor expressed in multiple immature cell populations, such as neuronal precursors, mesenchymal stem cells, and preadipocytes, where it regulates lineage allocation, proliferation, and differentiation. Here, we show that Zfp423 regulates myogenic progression during muscle regeneration. Zfp423 is undetectable in quiescent SCs but becomes expressed during SC activation. After expansion, Zfp423 is gradually downregulated as committed SCs terminally differentiate. Mice with satellite-cell-specific Zfp423 deletion exhibit severely impaired muscle regeneration following injury, with aberrant SC expansion, defective cell cycle exit, and failure to transition efficiently from the proliferative stage toward commitment. Consistent with a cell-autonomous role of Zfp423, shRNA-mediated knockdown of Zfp423 in myoblasts inhibits differentiation. Surprisingly, forced expression of Zfp423 in myoblasts induces differentiation into adipocytes and arrests myogenesis. Affinity purification of Zfp423 in myoblasts identified Satb2 as a nuclear partner of Zfp423 that cooperatively enhances Zfp423 transcriptional activity, which in turn affects myoblast differentiation. In conclusion, by controlling SC expansion and proliferation, Zfp423 is essential for muscle regeneration. Tight regulation of Zfp423 expression is essential for normal progression of muscle progenitors from proliferation to differentiation.

Role of transforming growth factor-beta1 in cyclosporine-induced epithelial-to-mesenchymal transition in gingival epithelium.

BACKGROUND: It has been proposed that cyclosporin A (CsA) may induce epithelial-to-mesenchymal transition (EMT) in gingiva. The aims of the present study are to confirm the notion that EMT occurs in human gingival epithelial (hGE) cells after CsA treatment and to investigate the role of transforming growth factor beta1 (TGF-ß1) on this CsA-induced EMT. METHODS: The effects of CsA, with and without TGF-ß1 inhibitor, on the morphologic changes of primary culture of hGE cells were examined in vitro. The changes of protein and messenger RNA (mRNA) expressions of two EMT markers (E-cadherin and alpha-smooth muscle actin) in the hGE cells after CsA treatment with and without TGF-ß1 inhibitor were evaluated with immunocytochemistry and real-time polymerase chain reaction. RESULTS: The epithelial cells became spindle-like, elongated, and disassociated from neighboring cells and lost their original cobblestone monolayer pattern when CsA was added. However, the epithelial cells stayed in their original cobblestone morphology with treatment of TGF-ß1 inhibitor on top of the CsA treatment. When CsA was given, the protein and mRNA expressions of E-cadherin and α-SMA were significantly altered, and these alterations were significantly reversed with pretreatment of TGF-ß1 inhibitor. CONCLUSIONS: CsA could induce Type 2 EMT in gingiva by changing the morphology of epithelial cells and altering the EMT markers/effectors. The CsA-induced gingival EMT is dependent or at least partially dependent on TGF-ß1.

Administrative trends in U.S. dental schools.

The aims of this study were to analyze the administrative trends in U.S. dental schools at the beginning and end of a thirteen-year period and to identify the predictive factors for those changes. Administrative trends were measured by the difference in the number of major administrative positions for 1997 and 2010 reported in American Dental Education Association (ADEA) and American Dental Association (ADA) publications. Secondary measures (program length, student enrollment, and tuition) were also gathered. The mean numbers of administrative positions per school significantly increased over the study period, while the mean number of clinical science departments per school significantly decreased. The change in the number of directors was positively correlated with the change in student enrollment, but inversely correlated with the change in number of vice/associate/assistant deans. The change in the number of clinical science departments was positively correlated with changes in student enrollment and out-of-state tuition, but inversely correlated with the change in in-state tuition. The number of all departments per U.S. dental school significantly decreased in this period. The schools that had consolidation of clinical science departments were less likely to have increases in student enrollment and out-of-state tuition, but more likely to have increases in in-state tuition.

Systematic review and meta-analysis of randomized controlled trials for the management of limited vertical height in the posterior region: short implants (5 to 8 mm) vs longer implants (> 8 mm) in vertically augmented sites.

PURPOSE: The aim of this study was to undertake a systematic review with meta-analysis on randomized controlled trials (RCTs) to compare the rates of survival, success, and complications of short implants to those of longer implants in the posterior regions. MATERIALS AND METHODS: Electronic literature searches were conducted through the MEDLINE (PubMed) and EMBASE databases to locate all relevant articles published between January 1, 1990, and April 30, 2013. Eligible studies were selected based on inclusion criteria, and quality assessments were conducted. After data extraction, meta-analyses were performed. RESULTS: In total, 539 dental implants (265 short implants [length 5 to 8 mm] and 274 control implants [length > 8 mm]) from four RCTs were included. The fixed prostheses of multiple short and control implants were all splinted. The mean follow-up period was 2.1 years. The 1-year and 5-year cumulative survival rates (CSR) were 98.7% (95% confidence interval [CI], 97.8% to 99.5%) and 93.6% (95% CI, 89.8% to 97.5%), respectively, for the short implant group and 98.0% (95% CI, 96.9% to 99.1%) and 90.3% (95% CI, 85.2% to 95.4%), respectively, for the control implant group. The CSRs of the two groups did not demonstrate a statistically significant difference. There were also no statistically significant differences in success rates, failure rates, or complications between the two groups. CONCLUSION: Placement of short dental implants could be a predictable alternative to longer implants to reduce surgical complications and patient morbidity in situations where vertical augmentation procedures are needed. However, only four studies with potential risk of bias were selected in this meta-analysis. Within the limitations of this meta-analysis, these results should be confirmed with robust methodology and RCTs with longer follow-up duration.

Association of CCL5 and CCR5 gene polymorphisms with periodontitis in Taiwanese.

BACKGROUND: It has been suggested that genetic factors may predispose individuals to periodontal diseases. The present case-control study aims to test whether the -403 single nucleotide polymorphism of chemokine ligand 5 (CCL5-403) and the 32-bp deletion of CCR5 (CCR5Δ32) polymorphisms are associated with susceptibility to chronic and aggressive periodontitis. METHODS: Taiwanese participants (N = 213) were grouped into control group (CG), generalized aggressive periodontitis (GAgP), or chronic periodontitis (CP) groups. DNA samples were obtained from peripheral blood. CCL5-403, evaluated by polymerase chain reaction-restriction fragment length polymorphism, and CCR5Δ32, evaluated by polymerase chain reaction, were compared among the three groups. RESULTS: There was a significant association between type of periodontitis and having allele A or G in the CCL5-403 polymorphism. GAgP patients were 3.7 times more likely than CP patients and 2.0 times more likely than CG patients to have allele A, instead of allele G, in CCL5-403. GAgP patients were 3.1 times more likely than CG patients to have AG versus GG genotype. GAgP patients were also 5.0 and 19.8 times more likely than CP patients to have AG and AA genotypes, respectively, compared to GG. For the CCR5Δ32 polymorphism, no association was found between the type of periodontitis and having different genotype or allele distributions among GAgP, CP, or CG patients. CONCLUSION: The single nucleotide polymorphism of CCL5-403 G substitution by A may play a role in AgP; however, the CCR5Δ32 polymorphism may not.

Direct transcriptional repression of Zfp423 by Zfp521 mediates a bone morphogenic protein-dependent osteoblast versus adipocyte lineage commitment switch.

Osteoblasts and adipocytes arise from a common mesenchymal precursor cell. The cell fate decision of a mesenchymal precursor cell is under the influence of molecular cues and signaling pathways that lead to the activation or repression of lineage-specific transcription factors. The molecular mechanisms determining osteoblast versus adipocyte lineage specificity in response to bone morphogenic protein (BMP) remain unclear. In this study, we describe the mechanism through which Zfp521 (ZNF521), a regulator of lineage progression in multiple immature cell populations, regulates lineage specification of mesenchymal progenitor cells during BMP-induced differentiation events. In vivo deletion or in vitro knockdown of Zfp521 in mesenchymal precursors resulted in increased expression of the adipocyte determinant factor Zfp423 (ZNF423). This was concurrent with the loss of histone H3K9 methylation and an increase in histone H3K9 acetylation at the Zfp423 promoter, which together are indicative of decreased gene repression. Indeed, we found that Zfp521 occupies and represses the promoter and intronic enhancer regions of Zfp423. Accordingly, conditional deletion of Zfp521 inhibited heterotopic bone formation in response to local injection of BMP2. In contrast, marrow adiposity within BMP2-induced bone was markedly enhanced in Zfp521-deficient mice, suggesting that precursor cells lacking Zfp521 differentiate preferentially into adipocytes instead of osteoblasts in response to BMP2. Consistent with a cell-autonomous role of Zfp521 in mesenchymal precursors, knockdown of Zfp521 in stromal cells prevented BMP2-induced osteoblast marker expression and simultaneously enhanced lipid accumulation and expression of adipocyte-related genes. Taken together, the data suggest that Zfp521 is a cell fate switch critical for BMP-induced osteoblast commitment and identify Zfp521 as the intrinsic repressor of Zfp423 and hence of adipocyte commitment during BMP-induced mesenchymal precursor differentiation.

Effects of enamel matrix derivative on the proliferation and osteogenic differentiation of human gingival mesenchymal stem cells.

INTRODUCTION: Gingiva-derived mesenchymal stem cells (GMSCs) have recently been harvested and applied for rebuilding lost periodontal tissue. Enamel matrix derivative (EMD) has been used for periodontal regeneration and the formation of new cementum with inserting collagen fibers; however, alveolar bone formation is minimal. Recently, EMD has been shown to enhance the proliferation and mineralization of human bone marrow mesenchymal stem cells. Because the gingival flap is the major component to cover the surgical wound, the effects of EMD on the proliferation and mineralization of GMSCs were evaluated in the present study. METHODS: After single cell suspension, the GMSCs were isolated from the connective tissues of human gingiva. The colony forming unit assay of the isolated GMSCs was measured. The expression of stem cell markers was examined by flow cytometry. The cellular telomerase activity was identified by polymerase chain reaction (PCR). The osteogenic, adipogenic and neural differentiations of the GMSCs were further examined. The cell proliferation was determined by MTS assay, while the expression of mRNA and protein for mineralization (including core binding factor alpha, cbfα-1; alkaline phosphatase, ALP; and osteocalcin, OC; ameloblastin, AMBN) were analyzed by real time-PCR, enzyme activity and confocal laser scanning microscopy. RESULTS: The cell colonies could be easily identified and the colony forming rates and the telomerase activities increased after passaging. The GMSCs expressed high levels of surface markers for CD73, CD90, and CD105, but showed low expression of STRO-1. Osteogenic, adipogenic and neural differentiations were successfully induced. The proliferation of GMSCs was increased after EMD treatment. ALP mRNA was significantly augmented by treating with EMD for 3 hours, whereas AMBN mRNA was significantly increased at 6 hours after EMD treatment. The gene expression of OC was enhanced at the dose of 100 µg/ml EMD at day 3. Increased protein expression for cbfα-1 at day 3, for ALP at day 5 and 7, and for OC at week 4 after the EMD treatments were observed. CONCLUSIONS: Human GMSCs could be successfully isolated and identified. EMD treatments not only induced the proliferation of GMSCs but also enhanced their osteogenic differentiation after induction.

Epigallocatechin-3-gallate attenuates Porphyromonas gingivalis lipopolysaccharide-enhanced matrix metalloproteinase-1 production through inhibition of interleukin-6 in gingival fibroblasts.

BACKGROUND: Recent studies have shown that epigallocatechin-3-gallate (EGCG), a major constituent of green tea extract, exhibits effects of anti-inflammation and antioxidation on periodontal inflammation. The present in vitro study examines the effect of EGCG on Porphyromonas gingivalis (Pg) lipopolysaccharide (LPS)-enhanced expression of interleukin (IL)-6 and matrix metalloproteinase (MMP)-1, as well as the activation of nuclear factor-kappa B (NF-κB). Furthermore, the role of IL-6 on LPS-enhanced MMP-1 production is evaluated using human gingival fibroblasts (HGFs). METHODS: HGFs were primary cultured from human gingiva specimens. The cytotoxicities of EGCG and LPS were tested by cell viability tests. The cellular mRNA expression of IL-6 was determined by reverse-transcription polymerase chain reaction, and the protein expression of MMP-1 and IL-6 was examined by enzyme-linked immunosorbent assay. The cytosol expression and nuclear translocation of NF-κB was evaluated by immunocytochemistry followed by confocal laser scanning microscopy. RESULTS: Pg LPS significantly increased MMP-1 production in HGFs, whereas adding EGCG significantly attenuated this enhanced production of MMP-1. LPS treatment also increased the mRNA and protein expression of IL-6 and stimulated NF-κB activation in HGFs. However, the addition of EGCG significantly attenuated the IL-6 expression and NF-κB activation. Supplemental addition of IL-6 significantly enhanced cellular MMP-1 production, whereas anti-IL-6 antibody inhibited LPS-enhanced MMP-1 production. CONCLUSION: EGCG could attenuate Pg LPS-enhanced production of MMP-1 in HGFs, whereas this attenuation might be due to the inhibition of IL-6 by EGCG.

Berberine's effect on periodontal tissue degradation by matrix metalloproteinases: an in vitro and in vivo experiment.

Periodontal disease involves tissue destruction caused by interactions among bacterial antigens and inflammatory mediators including matrix metalloproteinases (MMPs). Berberine, an isoquinoline alkaloid isolated from medicinal herbs, can inhibit the degradative action of extracellular MMPs. The effect of berberine on the periodontal expression of MMPs was examined in vitro and in vivo. Gelatinolytic activity of pro-MMP-2, MMP-2, and MMP-9 in the human gingival fibroblast and/or U-937 was compared after treatment with Porphyromonas gingivalis lipopolysaccharide (P.g. LPS) in four medias containing 0, 1, 10 and 100µM of berberine each. Twelve animals were divided into three groups for the study: (A) non-ligation, (B) ligation, and (C) ligation-plus-berberine (75mg/kg berberine by gastric lavage daily); and the effect of berberine on periodontal destruction was evaluated in the ligature-induced periodontitis in rats for 8 days by micro computerized tomography (micro-CT), histology and immunohistochemistry (IHC). An enhancing effect of P.g. LPS on MMP activities was identified, with a greater effect on fibroblasts/U937 co-culture than on either culture alone. When berberine was added to the LPS-treated cultures, the activities of MMPs were significantly reduced in dose-dependent manner. In the animals, the trends of the following parameters were compared. 1. Micro-CT distances between cemento-enamel junction (CEJ) and dental alveolar bone crest: B>C>A. 2. Histometrically measured crest bone levels: B>C>A. 3. Amount of collagen deposited in tissue areas: A>C>B. 4. Attachment loss: B>C≈A. 5. Connective tissue (CT) attachment: B>either A or C. 6. Expression of cells stained positive for MMP-2 and -9 by IHC: B>C>A. In conclusion, berberine demonstrated in vitro an inhibitory effect on P.g. LPS-enhanced MMP activities of HGF and U937 macrophages, reducing in vivo gingival tissue degradation in periodontitic rats. We thus propose that berberine may slow periodontal degradation through the regulation of MMPs in periodontitis induced by bacterial plaque.