Morbidity and mortality of oral cancer in Taiwan: Trends from 2000 to 2021.

Background/purpose: Oral cancer is a major cause of cancer morbidity and mortality worldwide, especially in Taiwan. This study investigated the morbidity and mortality of oral cancer in Taiwan from 2000 to 2021. Materials and methods: The population data and the records of cancer registry were obtained from the websites of the Ministry of the Interior and the Ministry of Health and Welfare, respectively. The numbers of oral cancer cases and deaths were analyzed from 2000 to 2021. Results: The numbers of oral cancer cases and deaths increased from 3378 to 1494 in 2000-8277 in 2020 and 3395 in 2021, respectively. The total increase of oral cancer cases was 4899 with a total increase rate of 145.03%, while the total increase of oral cancer deaths was 1901 with a total increase rate of 127.24%. The changes in the numbers of all cancer cases and deaths, as well as the morbidity and mortality of oral cancer or all cancers also showed similar trends. Furthermore, the death-to-case ratio of oral cancers decreased from 44.23% in 2000 to 40.84% in 2020. The total decrease was 3.39% with a total decrease rate of 7.66%. Conclusion: In Taiwan, people's awareness of oral mucosal health is still inadequate. Obviously, there is still much room for improvement in the oral mucosal health education for our people. With the expertise and responsibility for taking good care of oral health of our people, the dental personnel should take active roles in the prevention and screening for oral cancers.

Oral medicine education for medical students - A retrospective evaluation of the course in MacKay Medical College from 2016 to 2021.

Background/purpose: The oral medicine education for medical students is very important and a necessary part for the comprehensive medical education. The purpose of this study was to evaluate the oral medicine course for medical students by evaluating students' perspectives and the instructor's observation. Materials and methods: The medical students who took the compulsory course entitled "Introduction to Oral and Maxillofacial Medicine" in MacKay Medical College from 2016 to 2021 were invited to fill out the questionnaire for course satisfaction survey regarding their satisfied level with the course and their feelings about the instructors or suggestions, and the participatory observation was performed throughout the course activities and instructor-student interactions. Results: From 2016 to 2021, of a total of 268 medical students, 202 (75%) participated in the surveys. The results of the surveys and the instructor's observation showed that students satisfied with the course, and the course helped them to have a basic understanding of oral medicine. Moreover, all the mean scores and the rates of respondents who answered as agree for each item were 4.22-4.92 and 85%-100%, respectively. Conclusion: In this study, the oral medicine education for medical students contributed to an increase in students' awareness and understanding of oral health and dentistry. Considering the reported effectiveness of the course, students' satisfaction with the course content and teaching materials, and the instructor's teaching, this model of providing dental and oral health knowledge for the medical students may be a good one for further use in other medical institutions.

Prognostic Value of the Overexpression of Fatty Acid Metabolism-Related Enzymes in Squamous Cell Carcinoma of the Head and Neck.

Reprogramming of cellular energy metabolism, such as lipid metabolism, is a hallmark of squamous cell carcinoma of the head and neck (SCCHN). However, whether protein expression related to fatty acid oxidation (FAO) affects survival in SCCHN remains unclear. We aimed to investigate FAO-related enzyme expression and determine its correlation with clinicopathological variables in SCCHN patients. Immunohistochemical analysis (IHC) of FAO-related protein expression, including carnitine palmitoyltransferase 1 (CPT1), the acyl-CoA dehydrogenase family, and fatty acid synthase (FAS), was performed using tissue microarrays from 102 resected SCCHN tumors. Expressions were categorized according to IHC scores, and the statistical association with clinicopathological factors was determined. Moderate-to-high expression of long-chain acyl-CoA dehydrogenase (LCAD) had a protective role against cancer-related death (adjusted hazard ratio (HR), 0.2; 95% confidence interval (CI), 0.05-0.87) after covariate adjustment. Age and clinical stage remained independent predictors of survival (adjusted HR, 1.75; 95% CI, 1.22-2.49 for age; adjusted HR, 14.33; 95% CI, 1.89-108.60 for stage III/IV disease). Overexpression of medium-chain acyl-CoA dehydrogenase and FAS correlated with advanced tumor stage (T3/T4); however, none of these factors were independent predictors of survival. Several FAO-related enzymes were upregulated and LCAD overexpression had a protective effect on overall survival in advanced SCCHN patients. FAO-related-enzyme expression might have a prognostic impact on survival outcomes in SCCHN.

Gastric parietal cell and thyroid autoantibodies in patients with Behcet's disease.

BACKGROUND/PURPOSE: Gastric parietal cell antibody (GPCA), thyroglobulin antibody (TGA), and thyroid microsomal antibody (TMA) were rarely examined in Behcet's disease (BD) patients. This study mainly assessed the frequencies of serum GPCA, TGA, and TMA positivities in 63 BD patients. METHODS: The frequencies of serum GPCA, TGA, and TMA positivities in 63 BD patients, 19 major-typed recurrent aphthous stomatitis (RAS)/BD (major RAS/BD) patients, 44 minor-typed RAS/BD (minor RAS/BD) patients, 520 RAS patients, and 126 healthy control subjects were calculated and compared. RESULTS: We found that 14.3%, 20.6%, and 20.6% of 63 BD patients, 21.1%, 21.1%, and 26.3% of 19 major RAS/BD patients, 11.4%, 20.5%, and 18.2% of 44 minor RAS/BD patients, 11.5%, 18.5%, and 18.3% of 520 RAS patients, and 1.6%, 2.4%, and 2.4% of 126 healthy control subjects had serum GPCA, TGA, and TMA positivities, respectively. BD, major RAS/BD, minor RAS/BD, and RAS patients all had significantly higher frequencies of serum GPCA, TGA, and TMA positivities than healthy control subjects (all P-values < 0.05). However, there were no significant differences in different serum autoantibody frequencies between BD, major RAS/BD, or minor RAS/BD patients and RAS patients. Of 16 TGA/TMA-positive BD patients whose serum thyroid-stimulating hormone (TSH) levels were measured, 87.5%, 6.3%, and 6.3% of these TGA/TMA-positive BD patients had normal, lower, and higher serum TSH levels, respectively. CONCLUSION: Approximately 35% BD patients have serum GPCA/TGA/TMA positivity. However, BD patients do not have significantly higher frequencies of serum GPCA, TGA, and TMA positivities than RAS patients.

Controlled release of lovastatin from poly(lactic-co-glycolic acid) nanoparticles for direct pulp capping in rat teeth.

Statin at appropriate concentrations has been shown to induce odontoblastic differentiation, dentinogenesis, and angiogenesis. However, using a carrier to control statin release might reduce toxicity and enhance its therapeutic effects. The aim of this study was to prepare poly(d,l-lactide-co-glycolide acid) (PLGA) nanoparticles that contain lovastatin for application in direct pulp capping. The PLGA-lovastatin particle size was determined using dynamic light scattering measurements and transmission electron microscopy. In addition, the release of lovastatin was quantified using a UV-Vis spectrophotometer. The cytotoxicity and alkaline phosphatase (ALP) activity of PLGA-lovastatin nanoparticles on human dental pulp cells were investigated. Moreover, a real-time polymerase chain reaction (PCR) assay, Western blot analysis, and an enzyme-linked immunosorbent assay (ELISA) were used to examine the osteogenesis gene and protein expression of dentin sialophosphoprotein (DSPP), dentin matrix acidic phosphoprotein 1 (DMP1), and osteocalcin (OCN). Finally, PLGA-lovastatin nanoparticles and mineral trioxide aggregate (MTA) were compared as direct pulp capping materials in Wistar rat teeth. The results showed that the median diameter of PLGA-lovastatin nanoparticles was 174.8 nm and the cumulative lovastatin release was 92% at the 44th day. PLGA-lovastatin nanoparticles demonstrated considerably a lower cytotoxicity than free lovastatin at 5, 9, and 13 days of culture. For ALP activity, the ALP amount of PLGA-lovastatin (100 µg/mL) was significantly higher than that of the other groups for 9 and 13 days of culture. The real-time PCR assay, Western blot analysis, and ELISA assay showed that PLGA-lovastatin (100 µg/mL) induced the highest mRNA and protein expression of DSPP, DMP1, and OCN in pulp cells. Histological evaluation of the animal studies revealed that MTA was superior to the PLGA-lovastatin in stimulating the formation of tubular dentin in an observation period of 2 weeks. However, in an observation period of 4 weeks, it was evident that the PLGA-lovastatin and MTA were competitive in the formation of tubular reparative dentin and a complete dentinal bridge.

Anemia and hematinic deficiencies in gastric parietal cell antibody-positive and -negative oral mucosal disease patients with microcytosis.

BACKGROUND/PURPOSE: Microcytosis is defined as mean corpuscular volume (MCV) < 80 fL. This study assessed the anemia statuses and hematinic deficiencies in 30 patients with gastric parietal cell antibody-positive microcytosis (GPCA+/microcytosis) and 210 patients with GPCA-negative microcytosis (GPCA-/microcytosis). METHODS: We measured and compared the mean red blood cell (RBC) count, MCV, and RBC distribution width (RDW), as well as blood levels of hemoglobin, iron, vitamin B12, folic acid, and homocysteine among the aforementioned patient groups and 240 healthy controls. RESULTS: Compared with GPCA-/microcytosis, the positive counterparts presented with a lower mean serum vitamin B12 level (marginal significance), significantly higher mean RDW and serum homocysteine level, and significantly greater frequencies of vitamin B12 deficiency and high homocysteine level. GPCA-/microcytosis patients had significantly greater frequencies of hemoglobin, iron, vitamin B12, and folic acid deficiencies and of RBC count > 5 × 1012/L than healthy controls. Moreover, 19 of 30 GPCA+/microcytosis patients and 143 of 210 GPCA-/microcytosis patients had anemia, with iron deficiency anemia being the most common type, followed by thalassemia trait-induced anemia and microcytic anemia due to other causes. CONCLUSION: We conclude that GPCA in microcytosis patients' sera may have caused significantly lower mean vitamin B12 level as well as significantly higher mean RDW and serum homocysteine level in our GPCA+/microcytosis patients than in GPCA-/microcytosis patients. Herein, iron deficiency anemia was the most common type of anemia in anemic GPCA+/microcytosis and GPCA-/microcytosis patients.

Bacteria in the apical root canals of teeth with apical periodontitis.

BACKGROUND/PURPOSE: Bacteria in the tooth root canal may cause apical periodontitis. This study examined the bacterial species present in the apical root canal of teeth with apical periodontitis. Antibiotic sensitivity tests were performed to evaluate whether these identified bacterial species were susceptible to specific kinds of antibiotics. METHODS: Selective media plating and biochemical tests were used first to detect the bacterial species in samples taken from the apical portion of root canals of 62 teeth with apical periodontitis. The isolated bacterial species were further confirmed by matrix-assisted laser desorption ionization-time of flight mass spectrometry. RESULTS: We found concomitant presence of two (32 teeth) or three species (18 teeth) of bacteria in 50 (80.6%) out of 62 tested teeth. However, only 34 bacterial species were identified. Of a total of 118 bacterial isolates (83 anaerobes and 35 aerobes), Prophyromonas endodontalis was detected in 10; Bacteroides, Dialister invisus or Fusobacterium nucleatum in 9; Treponema denticola or Enterococcus faecalis in 8; Peptostreptococcus or Olsenella uli in 6; and Veillonella in 5 teeth. The other 25 bacterial species were detected in fewer than five teeth. Approximately 80-95% of bacterial isolates of anaerobes were sensitive to ampicillin/sulbactam (Unasyn), amoxicillin/clavulanate (Augmentin), cefoxitin, and clindamycin. For E. faecalis, 85-90% of bacterial isolates were sensitive to gentamicin and linezolid. CONCLUSION: Root canal infections are usually caused by a mixture of two or three species of bacteria. Specific kinds of antibiotic can be selected to control these bacterial infections after antibiotic sensitivity testing.

Anemia and hematinic deficiencies in anti-gastric parietal cell antibody-positive or all autoantibodies-negative recurrent aphthous stomatitis patients.

BACKGROUND/PURPOSE: Approximately 13% of recurrent aphthous stomatitis (RAS) patients have serum anti-gastric parietal cell antibody (GPCA) positivity. This study assessed whether serum GPCA or RAS itself was a significant factor causing hematinic deficiencies and anemia statuses in GPCA-positive RAS (GPCA+/RAS) and all autoantibodies-negative RAS (Abs-/RAS) patients. METHODS: The mean corpuscular volume (MCV) and mean blood hemoglobin (Hb), iron, vitamin B12, and folic acid levels were measured and compared between any two of three groups of 31 GPCA+/RAS patients, 240 Abs-/RAS patients, and 342 healthy control subjects. RESULTS: GPCA+/RAS patients had significantly lower mean Hb and serum iron level (for women only) as well as significantly greater frequencies of Hb, iron, and vitamin B12 deficiencies than healthy control subjects. Moreover, GPCA+/RAS patients had a significantly higher MCV and a significantly greater frequency of vitamin B12 deficiency than Abs-/RAS patients. Furthermore, Abs-/RAS patients did have significantly lower mean Hb, MCV, iron, and folic acid levels and significantly greater frequencies of Hb, iron, vitamin B12, and folic acid deficiencies than healthy control subjects. Of 31 GPCA+/RAS patients, 3 (9.7%) had PA, 6 (19.4%) had vitamin B12 deficiency, and 3 (9.7%) had macrocytosis. Moreover, normocytic anemia (54.0%) and iron deficiency anemia (26.4%) are the two more common types of anemia in our RAS patients. CONCLUSIONS: We conclude that serum GPCA plays a significant role in causing vitamin B12 deficiency and high MCV in GPCA+/RAS patients. RAS itself does play a significant role in causing anemia and hematinic deficiencies in both GPCA+/RAS and Abs-/RAS patients.

Langerhans cells in 60 odontogenic keratocysts.

BACKGROUND/PURPOSE: Langerhans cells (LCs) are antigen-presenting cells. This study mainly evaluated the LC counts in 60 odontogenic keratocysts (OKCs). MATERIALS AND METHODS: The CD1a-positive LC numbers in the lining epithelia and subepithelial connective tissues were counted at 60 OKC sites without inflammation, 39 OKC sites with mild/moderate inflammation, and 13 OKC sites with severe inflammation from 60 OKC specimens. RESULTS: The mean CD1a-positive LC counts in the lining epithelia and subepithelial connective tissues increased significantly from no inflammation (0.5 ± 0.4 and 0.2 ± 0.3 cell/high-power field or HPF, respectively) through mild/moderate inflammation (5.3 ± 2.5 and 2.5 ± 2.7 cells/HPF, respectively) to severe inflammation OKC sites (12.7 ± 5.6 and 9.3 ± 7.2 cells/HPF, respectively; all P-values < 0.001). OKC sites with inflammation had thicker lining epithelia than those without inflammation. Moreover, the mean CD1a-positive LC counts in the lining epithelia and subepithelial connective tissues of OKCs were significantly higher in the thicker lining epithelium (>100 µm) group (6.8 ± 5.1 and 3.7 ± 4.9 cells/HPF, respectively) than in the thinner lining epithelium (≦100 µm) group (1.0 ± 1.7 and 0.8 ± 2.5 cell/HPF, respectively; both P-values < 0.001). CONCLUSION: There is a significant association of inflammation grade with the number of LCs in OKCs. The scarce LCs in the lining epithelia of OKCs without inflammation suggests the loss of immunosurveillance ability against the OKC lining epithelial cells; this can explain why OKCs have aggressive clinical behavior, a great growth potential, and a high recurrence rate.

A functional chitosan membrane with grafted epigallocatechin-3-gallate and lovastatin enhances periodontal tissue regeneration in dogs.

Currently used guided tissue regeneration (GTR) membranes are mainly used as a barrier to prevent epithelial cells growth into defects before new bone formation. The aim of this study was to develop a tri-layer functional chitosan (CS) membrane with epigallocatechin-3-gallate (EGCG) grafted on the outer layer for bactericidal activity, and lovastatin was included in the middle layer for controlled release. Successful EGCG grafting was demonstrated using Fourier transform infrared spectroscopy and EGCG grafting significantly enhanced adhesion and proliferation of human gingival fibroblasts. The release duration of lovastatin reached 21days. CS-Lovastatin1 produced the highest alkaline phosphatase activity and EGCG14-CS exhibited the best bactericidal activity against periodontopathic bacteria. Finally, the EGCG14-CS-Lovastatin1 membrane showed a higher percentage of bone regeneration than BioMend(®) and control groups in one-walled defects of beagle dogs. These results suggest that the EGCG14-CS-Lovastatin1 membrane has the potential to be used as a novel GTR membrane.

Non-calcifying and Langerhans cell-rich variant of calcifying epithelial odontogenic tumor.

This study reported the clinicopathological features, treatment and prognosis of nine cases of noncalcifying and Langerhans cell (LC)-rich calcifying epithelial odontogenic tumor (CEOT) collected from the English literature. Of the nine cases, seven were intraosseous and two were extraosseous. All nine tumors were found in Asian patients. The age of the nine patients ranged from 20 years to 58 years with a mean age of 41 years. There were five female and four male patients. The seven intraosseous cases included six in the anterior and premolar region of the maxilla and one in the posterior region and ascending ramus of the mandible. The two extraosseous cases were located at the upper lateral incisor and premolar gingivae, respectively. Of the seven intraosseous cases, five showed unilocular and two multilocular radiolucency without foci of calcification. Six of the seven intraosseous cases showed resorption of the tooth roots in the tumor-involved region. Histologically, noncalcifying and LC-rich CEOTs were composed of small nests and thin strands of tumor epithelial cells with a relatively high number of LCs among them. This was the reason why we classed these nine cases as noncalcifying and LC-rich CEOTs. Two extraosseous cases received total excision of the gingival mass. For the seven intraosseous cases, four accepted partial maxillectomy or mandibulectomy, two received total excision or enucleation, and one underwent curettage. The six cases with the follow-up information available showed no tumor recurrence after a follow-up period of 6 months to 10 years.

Cryogun cryotherapy for oral leukoplakia and adjacent melanosis lesions.

BACKGROUND: Our previous study has shown that cryogun cryotherapy is a good and effective treatment modality for oral leukoplakia. METHODS: In this study, we used cryogun cryotherapy to treat 72 oral leukoplakia and adjacent smoking-induced melanosis (OLM) lesions on the buccal mucosae. RESULTS: Of 72 OLM lesions, 14 had epithelial hyperplasia with parakeratosis, 24 had epithelial hyperplasia with hyperkeratosis, 26 had mild dysplasia, seven had moderate dysplasia, and one had severe dysplasia. Complete regression was achieved in all 72 OLM lesions after a mean of 3.3 ± 1.3 cryogun cryotherapy treatments. We found that OLM lesions in patients without smoking habit, with the greatest diameter < 2.8 cm, with epithelial dysplasia, or with a surface keratin thickness ≤ 50 µm needed significantly fewer mean number of cryogun cryotherapy treatment to achieve complete regression than those OLM lesions in patients with smoking habit, with the greatest diameter ≥ 2.8 cm, without epithelial dysplasia, or with a surface keratin thickness > 50 µm (all P-values < 0.001), respectively. Univariate logistic regression analyses showed that the greatest diameter, epithelial dysplasia, smoking habit, and surface keratin thickness were the factors influencing the cryogun cryotherapy treatment number (all P-values < 0.001). However, only the greatest diameter < 2.8 cm (P < 0.001) was an independent factor influencing the number of cryogun cryotherapy treatment required to achieve complete regression of the OLM lesion by multivariate logistic regression analyses. CONCLUSION: Cryogun cryotherapy is an effective treatment modality for OLM lesions.