Onset of oral lichen planus following dental treatments: A nested case-control study.

INTRODUCTION: The exposure to amalgam restorations has been reported to bring about altered immunity followed by inflammation and infection. AIMS: This study aimed at identifying whether patients who received restorative or endodontic treatments, or tooth extraction, would have altered odds of developing oral lichen planus (OLP). MATERIAL AND METHODS: In this population-based nested case-control study, 421 cases of OLP and 1,684 controls were included after propensity score matching. Logistic regression was used to estimate the adjusted odds ratio (aOR) of OLP in individuals who had received amalgam and composite resin restorations, root canal therapy, and tooth extraction over a follow-up duration of five years. RESULTS: There were no significantly different odds of OLP for those who underwent either amalgam (aOR = 0.948, 95% CI = 0.853-1.053, p = 0.3170) or resin restorations (aOR = 1.007, 95% CI = 0.978-1.037, p = 0.6557) in both anterior and posterior teeth in an observational period of five  years after restorations. Root canal therapy was associated with significantly lower odds of OLP, with each additional root canal therapy attenuating the risk of OLP at an aOR of 0.771 (95% CI = 0.680-0.874, p = 0.0001) for both anterior (aOR = 0.786, 95% CI = 0.626-0.986, p = 0.0372) and posterior teeth (aOR = 0.762, 95% CI = 0.650-0.893, p = 0.0008). Likewise, each tooth extraction reduced the risk of OLP, with an aOR of 0.846 (95% CI = 0.772-0.927, p = 0.0003), especially for anterior teeth (aOR = 0.733, 95% CI = 0.595-0.904, p = 0.0037). CONCLUSIONS: We reported no significant association between dental restorations and consequent OLP, and significantly lower odds of OLP following both root canal therapy and tooth extraction.

Periodontitis is associated with incidental valvular heart disease: A nationwide population-based cohort study.

AIM: Periodontitis and valvular heart disease (VHD) are common diseases. Both diseases are related to chronic inflammation and share many common risk factors. Previous periodontal studies had focused mainly on atherosclerotic cardiovascular disease. This study aimed to determine whether periodontitis is associated with the development of VHD. MATERIALS AND METHODS: This was a retrospective nationwide cohort study using Taiwan's Longitudinal Health Insurance Database. Using ICD-9-CM coding, both the periodontitis and non-periodontitis groups were matched. RESULTS: There were 8483 cases and 4919 cases of VHD diagnosed in the periodontitis group and non-periodontitis group, respectively. The cumulative incidence of VHD was significantly higher in the periodontitis group (log-rank test, p < .001), with the incidence density of 6.44 (95% CI, 6.31-6.58) per 1000 person-years in the periodontitis group compared to 4.65 (95% CI, 4.52-4.78) in the non-periodontitis group. The relative risk for VHD was 1.39 (95% CI, 1.34-1.44). After multivariate analysis, periodontitis was independently associated with a risk for VHD (HR, 1.38; 95% CI, 1.33-1.42, p < .001). Intensive treatment of periodontitis significantly lowered the risk for VHD (HR, 0.68; 95% CI, 0.60-0.77, p < .001). CONCLUSIONS: Periodontitis was significantly associated with the development of VHD. Treatment of periodontitis reduced the risk for VHD.

Hinokitiol ablates myofibroblast activation in precancerous oral submucous fibrosis by targeting Snail.

Oral submucous fibrosis (OSF) is a precancerous condition with symptoms of limited mouth opening and areca nut chewing habit has been implicated in its pathogenesis. Hinokitiol, a natural tropolone derived from Chamacyparis taiwanensis, has been reported to improve oral lichen planus and inhibit various cancer cells. Here, we showed that hinokitiol reduced the myofibroblast activities in fBMFs and prevented the arecoline-induced transdifferentiation. Treatment of hinokitiol dose-dependently downregulated the myofibroblast markers as well as various EMT transcriptional factors. In particular, we identified that Snail was able to bind to the E-box in the α-SMA promoter. Our data suggested that exposure of fBMFs to hinokitiol mitigated the hallmarks of myofibroblasts, while overexpression of Snail eliminated the effect of hinokitiol. These findings revealed that the inhibitory effect of hinokitiol on myofibroblasts was mediated by repression of α-SMA via regulation of Snail and showed the anti-fibrotic potential of hinokitiol in the treatment of OSF.

Intraosseous verrucous carcinoma arising from an infected dentigerous cyst-A case report.

Intraosseous verrucous carcinoma (IOVC) arising from an odontogenic cyst is extremely rare. We report a case of intraosseous verrucous carcinoma in a 74-year-old male who presented with a left mandibular swelling with recurrent pus discharge from gingiva of tooth #35. Panoramic radiography revealed an impacted tooth #34 and a large well-defined, radiolucent lesion surrounding the crown of tooth #34. The clinical diagnosis was an infected dentigerous cyst. Surgical excision of the cyst together with extraction of tooth #34 was performed. Histopathological examination showed proliferation of hyperparakeratotic stratified squamous cyst lining epithelium and down-growth of broad and bulbous epithelial ridges with pushing border invasion into the fibrous cystic wall. A verrucous carcinoma arising from an infected dentigerous cyst was diagnosed. There was no recurrence of the tumor 5 months after surgery.

Synergistic antibacterial effects of 5-fluorouracil or thioridazine in combination with phytopolyphenols on cultured Porphyromonas gingivalis.

Background/purpose: 5-Fluorouracil (5FU) is a commonly used anticancer drug. However, the severe oral mucositis induced by 5FU in about 60-70% of patients was a major cause of discontinuous therapy. Since oral dysbiosis induced by 5FU was well correlated with severity of oral mucositis and Porphyromonas gingivalis (P.g.) was a keystone pathogen of dysbiosis. Thus, in this study, we aimed to explore the novel regimens of 5FU combined with phytopolyphenols (curcumin, green tea polyphenols) as well as ZnSO4 on antibacterial effects of cultured P.g. growth. In addition, similar regimens containing thioridazine (TRZ) were also tested for their antibacterial efficacy. Materials and methods: The synergistic (Combination Index (CI) < 1) antiproliferation and anti-protease efficacies (IC50) of novel regimens on cultured P.g. were evaluated by OD600 and colorimetric method respectively. Results: The results obtained indicated that both novel regimens of 5FU and TRZ exhibited potent synergistic antibacterial effects against growth and protease of P.g. Conclusion: These novel regimens of 5-FU and TRZ were potent antibacterial agents which merit for further preclinical and clinical trials in management of oral mucositis, cancers and infectious diseases.

Novel regimens of phytopolyphenols with cisplatin or memantine and ZnSO4 for synergistic inhibition of growth and gingipains of the cultured Porphyromonas gingivalis.

Background/purpose: Porphyromonas gingivalis (P.g.) played a keystone pathogen not only in initiation and progression of periodontitis but also as a risk factor involved in systemic diseases (Alzheimer's disease, cancers, diabetes, osteoporosis etc.). Developments of effective and safe drugs to inhibit P.g. growth are urgent. In this study, we aimed at approaching novel regimens so called (PTM) by combination of repurposing drugs including phytopolyphenols (P) (curcumin, tea polyphenols), targeting drugs (T) such as cisplatin or memantine and metal ions(M) (ZnSO4). Materials and methods: The synergistic (combination Index (CI) < 1) antiproliferation and anti-protease efficacies (IC50) of novel regimens on cultured P.g. were evaluated by OD600 and colorimetric method respectively. Results: The results obtained revealed that these novel regimens (PTM) synergistically (combination index, CI < 1) exerted not only antiproliferative but also anti-gingipain protease effects of P.g. The concentrations for 50% inhibition (IC50) of novel regimens on P.g. growth and gingipains were greatly decreased as compared with those of cisplatin and memantine alone. Conclusion: Since these novel regimens exerted potent anti-bacterial effects on both planktonic and biofilm P.g., it is encouraged for further preclinical and clinical trials.

Oral microbiota in xerostomia patients - A preliminary study.

BACKGROUND/PURPOSE: The estimated prevalence of xerostomia (lack of saliva) ranges from 10% to 50% of the general population. The oral cavity provides a multivariant environmental habitat to over 700 species of bacteria and fungi. We hypothesized that xerostomia will alter the composition of oral microbiota. MATERIAL AND METHODS: Nineteen xerostomia patients and 10 healthy normal volunteers were studied for the oral microbiota. Gingival plaques were collected and microbiota were detected using bacterial 16S ribosomal RNA and analyzed based on the levels of phylum and class. RESULTS: In all cases, phyla of Actinobacteria, Bacteroidetes, Firmicutes, Fusobacteria, and Proteobacteria make up to 100% of oral microbiota at phylum level. Analyzing individual phylum, presence of Bacteroidetes in xerostomia patients and normal subjects were 23.12 ± 2.56% and 23.23 ± 2.58%, respectively. Mean percentage presence of Firmicutes phylum in xerostomia patients and normal subjects were 18.94 ± 1.83% and 14.06 ± 0.98%, respectively. Statistically significant difference was not observed between xerostomia patients and normal subjects in this study. CONCLUSION: These observations revealed obvious but not statistically significant changes in oral major microorganism phylum between xerostomia patients and normal subjects in this study. More samples are needed to verify the current results and to use oral microbiota as a tool in the diagnosis of xerostomia.

Improving the Diagnostic Performance by Adding Methylation Marker to Conventional Visual Examination in Identifying Oral Cancer.

BACKGROUND: Visual oral examination (VOE) is a conventional oral cancer screening method. This study aimed to evaluate the value of methylation marker to assist VOE in identifying oral epithelial dysplasia and oral squamous cell carcinoma (OED/OSCC) from non-cancerous lesions in a real-world situation. METHODS: 201 patients with high-risk personal habits who self-perceived oral anomaly were VOE examined, ZNF582 methylation (ZNF582m) tested, and histologically diagnosed. RESULTS: Among them, 132 patients (65.7%) were histologically diagnosed OED/OSCC. Using VOE, 56.1% OED/OSCC patients had possible oral cancer, whereas 37.7% non-OED/OSCC patients had leukoplakia. ZNF582m-positive was detected in 90.2% OED/OSCC patients and 44.9% non-OED/OSCC patients. Various logistic regression models were postulated to evaluate the diagnostic performance of conventional VOE and new strategies using ZNF582m. ROC analysis and its corresponding C-index demonstrated that either triage or co-testing models of VOE and ZNF582m could improve diagnostic performance and discriminative abilities compared with the VOE only approach. CONCLUSIONS: In conclusion, methylation marker test shows equivalent performance to an experienced judgment by oral maxillofacial surgeons and plays a significantly supplementary role in increasing the efficacy in identifying oral malignant lesions. ZNF582m may be an especially important tool for family physicians or general dentists to properly diagnose suspicious oral lesions.

Component effects of bioactive glass on corrosion resistance and in vitro biological properties of apatite-matrix coatings.

BACKGROUND: Surface modification of metallic implants is critical for improving the clinical performance of the dental and orthopedic devices. Bioactive glasses exhibit different levels of cellular function and physicochemical behavior; however, there have been few previous studies on the effect of constituents of the bioactive glasses on the in vitro osteogenic activity and corrosion resistance of apatite-based coatings. OBJECTIVE: The objective of this work was to investigate the effect of SiO2, CaO, Na2O, and P2O5 on plasma-sprayed apatite coatings on Ti alloy substrates for tailoring the properties of implants making them suitable for clinical applications. METHODS: The corrosion potential and corrosion current of various coatings in simulated body fluid (SBF) were examined. MG63 cell proliferation, differentiation, and mineralization of plasma-sprayed apatite-matrix coatings were evaluated. RESULTS: The SiO2 and CaO-containing HA (HSC) coating had a higher corrosion potential than the other three coatings, while SiO2-containing HA (HS) coating displayed the highest corrosion current among all coatings. The effect of the oxides on cell functions followed the order SiO2 > CaO > P2O5 > Na2O in terms of cell attachment, proliferation, differentiation, and mineralization. CONCLUSIONS: The flexibility in oxide doping may allow for the tunable biological properties and corrosion-resistant ability of the apatite coatings.

A novel RNA-splicing mutation in COL1A1 gene causing osteogenesis imperfecta type I in a Chinese family.

BACKGROUND: Osteogenesis imperfecta (OI), also known as brittle bone disease, is a rare heterogeneous group of inherited disorders characterized by low bone mass and increased bone fragility. The four major clinical criteria for diagnosis of OI are osteoporosis with abnormal fragility of the skeleton, blue sclera, dentinogenesis imperfecta, and premature otosclerosis. The presence of two of these abnormalities confirms the diagnosis. More than 90% patients have autosomal dominant mutations in one of the two genes, COL1A1 and COL1A2, that encode the alpha chains of type I collagen. While the diagnosis of OI is still based on clinical and radiological grounds, there is a growing demand for the molecular characterization of causative mutations. Although there have been several studies on the mutational spectra of COL1A1 and/or COL1A2 in Western populations, very few cases have been reported from Asia. The purpose of this study is to report two patients with OI type I in a Chinese family, who had a novel RNA-splicing mutation in COL1A1 gene and describe the molecular, radiological and clinical findings. METHODS: The proband, (case II-5), a 32-y-old Chinese male, and his 7-y-old daughter were diagnosed as OI type I according to their clinical and radiological features. Genomic DNA was extracted from their blood samples and all promoters, exons and exon/intron boundaries of COL1A1 and COL1A2 genes were sequenced. Polymerase chain reaction sequence-specific primers (PCR-SSP) was used to confirm patients' heterozygous state. RESULTS: Direct DNA sequencing analysis of COL1A1 gene revealed a splicing mutation (c.1875+1G>A, also as IVS 27+1G>A) that converted the 5' end of intron 27 from GT to AT. This mutation was found in both 2 affected individuals but 9 unaffected relatives and the 50 controls were not observed, which was consistent with the clinical diagnosis. This mutation (c.1875+1G>A) appeared to be novel, which is neither reported in literature nor registered in the Database of Collagen Mutations. The heterozygous states of patients' intron 27 were confirmed by PCR-SSP. CONCLUSION: We identify a novel RNA-splicing mutation (c.1875+1G>A) in COL1A1 gene resulting in OI type I in a Chinese family. The detailed molecular and clinical features will be useful for extending the evidence for genetic and phenotypic heterogeneity in OI and exploring the phenotype-genotype correlations in OI.

Occurrence of Porphyromonas gingivalis and Tannerella forsythensis in periodontally diseased and healthy subjects.

BACKGROUND: The purpose of this study was to compare the prevalence and level of Porphyromonas gingivalis (P. gingivalis) and Tannerella forsythensis (T. forsythensis) in subgingival plaque samples from both healthy individuals and periodontal patients in different age groups. METHODS: A total of 498 subgingival plaque samples were studied. These samples were collected from 407 individuals diagnosed with periodontal disease (210 adult periodontitis [AP], 78 rapidly progressive periodontitis [RPP], and 119 refractory periodontitis [Ref-P] cases) and 91 healthy (H) subjects. P. gingivalis and T. forsythensis were detected by indirect immunofluorescent assay using species-specific polyclonal antisera to P. gingivalis strain (FDC 381) and T. forsythensis strain (FDC 335). The prevalence of P. gingivalis and T. forsythensis was compared by chi-square analysis. Differences in P. gingivalis and T. forsythensis levels among various periodontal status and age groups was determined by one-way analysis of variance and Fisher's multiple comparison tests. The association between the presence of P. gingivalis or T. forsythensis in different periodontal status and age groups was measured using odds ratios. RESULTS: P. gingivalis was found in 85.7% (P < 0.0001) and T. forsythensis in 60.7% (P = 0.0002) of diseased subjects compared to 23.1% and 39.6%, respectively, in healthy subjects. P. gingivalis, but not T. forsythensis, was detected more frequently in any diseased group than in the H group in every age group (P<0.0001). No significant difference was found in the prevalence of P. gingivalis and T. forsythensis among age groups, except T. forsythensis was more prevalent in the age group of 40 to 59 years than in the age group < 20 years (chi2 = 3.93, P = 0.047) in the H group. The mean level of P. gingivalis and T. forsythensis was significantly higher in diseased groups than in the H group (P < 0.0001). The odds ratio for P. gingivalis in the AP group (25.0) was greater than any other group for P. gingivalis or T. forsythensis compared to the H group. CONCLUSIONS: These data suggested that P. gingivalis is closely associated with the pathogenesis of periodontitis and that it may not be a normal inhabitant of periodontally healthy subjects. T. forsythensis is also important in the pathogenesis of periodontal disease; however, whether it causes periodontal disease or is a secondary invader of periodontal lesions remains to be determined.

Item response analysis on an examination in anesthesiology for medical students in Taiwan: a comparison of one- and two-parameter logistic models.

BACKGROUND: Student examinations are an essential component of medical education and item analyses are important to assess test quality. Among miscellaneous psychometric theories used for test analyses, item response theory is more flexible and versatile than other theories. This study aimed to apply item response models to analyze an anesthesiology examination for medical and dental students. METHODS: This examination included 50 items that were administered to 170 5(th)- and 6(th)-year medical and dental students. One- and two-parameter logistic (1-PL and 2-PL) item response models were used to conduct item analyses of the examination. Fit statistics were examined to exclude misfit items and evaluate test reliability. Goodness-of-fit analyses were used to select the model having the better fit to data. Examinee's ability and item difficulty were estimated and then expressed on the common scale. Potentially differential items were detected using logistic regression. RESULTS: The goodness-of-fit analysis revealed that, in our case, the 1-PL model was more suitable for item response analyses. No misfit item was noted and the test reliability was 0.81 (1-PL model). The mean examinee's ability was set at 0 by definition [standard deviation (SD) = 0.61] and the mean item difficulty was -2.08 (SD = 1.93). There were 24 items with a difficulty level lower than the least able examinee, and three items had a difficulty level higher than the most able examinee. Four potentially differential items were identified. CONCLUSION: Item response models are useful for medical test analyses and provide valuable information about model comparisons and identification of differential items other than test reliability, item difficulty, and examinee's ability.

Treatment of burning mouth syndrome with a low-level energy diode laser.

OBJECTIVE: To test the therapeutic efficacy of low-level energy diode laser on burning mouth syndrome. BACKGROUND: Burning mouth syndrome is characterized by burning and painful sensations in the mouth, especially the tongue, in the absence of significant mucosal abnormalities. Although burning mouth syndrome is relatively common, little is known regarding its etiology and pathophysiology. As a result, no treatment is effective in all patients. Low-level energy diode laser therapy has been used in a variety of chronic and acute pain conditions, including neck, back and myofascial pain, degenerative osteoarthritis, and headache. METHODS: A total of 17 patients who had been diagnosed with burning mouth syndrome were treated with an 800-nm wavelength diode laser. A straight handpiece was used with an end of 1-cm diameter with the fiber end standing 4 cm away from the end of handpiece. When the laser was applied, the handpiece directly contacted or was immediately above the symptomatic lingual surface. The output used was 3 W, 50 msec intermittent pulsing, and a frequency of 10 Hz, which was equivalent to an average power of 1.5 W/cm(2) (3 W × 0.05 msec × 10 Hz = 1.5 W/cm(2)). Depending on the involved area, laser was applied to a 1-cm(2) area for 70 sec until all involved area was covered. Overall pain and discomfort were analyzed with a 10-cm visual analogue scale. RESULTS: All patients received diode laser therapy between one and seven times. The average pain score before the treatment was 6.7 (ranging from 2.9 to 9.8). The results showed an average reduction in pain of 47.6% (ranging from 9.3% to 91.8%). The burning sensation remained unchanged for up to 12 months. CONCLUSION: Low-level energy diode laser may be an effective treatment for burning mouth syndrome.

Treatment of persistent idiopathic facial pain (PIFP) with a low-level energy diode laser.

OBJECTIVE: The purpose of this study was to test the therapeutic efficacy of low- level energy diode laser on persistent idiopathic facial pain (PIFP). BACKGROUND DATA: PIFP has presented a diagnosis and management challenge to clinicians. Many patients were misdiagnosed, which resulted in unnecessary dental procedures. Low-level energy diode laser therapy has been applied to different chronic and acute pain disorders, including neck, back, and myofacial pain; degenerative osteoarthritis; and headache, and it may be an effective alternative treatment for PIFP. METHODS: A total of 16 patients, who were diagnosed with PIFP, were treated with an 800-nm wavelength diode laser. A straight handpiece having an end size of 0.8 cm in diameter, or an angled handpiece with an end size of 0.5 cm in diameter was used. When laser was applied, the handpiece directly contacted the involved symptomatic region with an energy density of 105 J/cm(2). Overall pain and discomfort was analyzed with a 10-cm visual analogue scale (VAS) before and after treatment. RESULTS: All patients received diode laser therapy between 1 and 10 times. The average pain score was 7.4 before the treatment (ranging from 2.9 to 9.8), and 4.1 after the treatment. An average pain reduction of 43.87% (ranging from 9.3% to 91.8%) was achieved. The pain remained unchanged at a lower level for up to 12 months. CONCLUSIONS: Low-level energy diode laser may be an effective treatment for PIFP.

Prevention of dental damage and improvement of difficult intubation using a paraglossal technique with a straight Miller blade.

Patients with diseased teeth, or those who are difficult to intubate, have a higher risk of dental injury during laryngoscopy. We report 3 cases of smooth endotracheal intubation using a paraglossal technique with a straight Miller blade in patients with poor dentition. Three patients with poor dentition were scheduled to undergo surgery under general anesthesia. All patients presented with extremely loose upper central incisors and had lost the other right upper teeth, while micrognathia and prominent, loose upper incisors were noted in 1 case. We elected to use a straight Miller blade using a paraglossal approach. A nasopharyngeal airway was inserted after induction of general anesthesia to facilitate mask ventilation and prevent air leakage from the mask. The Miller blade was then inserted from the right corner of the mouth, avoiding contact with the vulnerable incisors, and advanced along the groove between the tongue and tonsil. The endotracheal tube was subsequently smoothly inserted after obtaining a grade 1 Cormack and Lehane view without dental trauma in all 3 cases. Direct laryngoscopy using the paraglossal straight blade technique avoids dental damage in patients with mobile upper incisors and no right maxillary molars. It is a practical alternative method that differs from the traditional Macintosh laryngoscope in patients with a high risk of dental injury during the procedure. This technique, which provides an improved view of the larynx, might also be helpful with patients in whom intubation is difficult.

Relationship of Actinobacillus actinomycetemcomitans serotypes to periodontal condition: prevalence and proportions in subgingival plaque.

No study available has utilized the new classification scheme (the consensus report of the American Academy of Periodontology 1999) to determine the prevalence of Actinobacillus actinomycetemcomitans in different periodontal conditions. The purpose of this study was to investigate prevalence and proportions of A. actinomycetemcomitans serotypes in subgingival plaque samples from a young Taiwanese population with aggressive periodontitis, chronic periodontitis and no periodontal disease. A total of 221 subgingival plaque samples from 171 diseased subjects (70 had aggressive periodontitis, and 101 had chronic periodontitis) (mean age 25.0 +/- 8.2 yr) and 50 periodontally healthy subjects (mean age 18.4 +/- 9.5 yr) were screened for A. actinomycetemcomitans. Serotypes of A. actinomycetemcomitans were determined by an indirect immunofluorescence assay using serotype-specific polyclonal antisera to A. actinomycetemcomitans strains ATCC 29523 (serotype a), ATCC 43728 (serotype b) and ATCC 33384 (serotype c). Prevalence (% of positive samples) of A. actinomycetemcomitans was 84.3% in aggressive periodontitis, 60.4% in chronic periodontitis, and 64.0% in periodontally healthy subjects. Proportions of A. actinomycetemcomitans (mean percentage per total bacteria) in periodontally healthy subjects were significantly lower than in aggressive periodontitis subjects. The proportion of serotype b in subjects with aggressive periodontitis and subjects with chronic periodontitis were significantly greater than that in periodontally healthy subjects. The proportion of serotype c in periodontally healthy subjects was much higher than that in chronic periodontitis subjects. The results of this study suggest that prevalence and proportions of A. actinomycetemcomitans are significantly greater in patients with aggressive periodontitis than in those with chronic periodontitis. Serotype b is the predominant serotype of A. actinomycetemcomitans in patients with diseased periodontal conditions. Serotype c is a more common serotype detected in periodontally healthy subjects.