Giant lipoma of the tongue: A case report and review of the literature

This report presents the case of a 49-year-old man who presented with giant masses that had recently grown on the bilateral sides of the tongue. A clinical examination revealed rubbery yellowish lesions protruding from the tongue.A panoramic radiograph showed an enlarged soft tissue shadow of the tongue. Computed tomography showed well-defined circumscribed mass exhibiting a homogeneous low density on the bilateral sides of the tongue. On magnetic resonance images, the masses showed a high signal intensity on T1-weighted images and iso-signal intensity with partially hyperintense margin on fat-suppressed T2-weighted images. Surgical excision was performed, and a histopathologic examination confirmed the diagnosis of lipoma. The patient recovered well with no sign ofrecurrence. A giant lipoma is defined as a lipoma larger than 5 cm in diameter. A literature review of giant lipomas of the tongue is also presented herein.

Perceptions and attitudes of dental hygienists toward radiation safety and protection in the Republic of Korea

To investigate the perceptions and attitudes of dental hygienists toward radiation safety management in Korea. A total of 800 dental hygienists were randomly selected for an anonymous survey, and 203 of them participated. The questionnaire items included the following: sex, career period, type of installed radiographic equipment, recognition of the diagnostic reference level (DRL), participation in radiation safety education, and attitudes toward radiation protection for both patients and dental hygienists. The participants were divided into two groups according to their years of experience (< 10 years versus ≥ 10 years). The difference between the groups was investigated according to frequency distribution. Fisher’s exact test or Pearson’s chi-square (χ2 ) test was used as appropriate. A regression analysis was performed to investigate the impact of wearing a thyroid collar for personnel protection during patient radiation exposure. The types of installed radiographic equipment included panoramic radiography (96.1%), cephalometric radiography (76.9%), intraoral radiography (72.9%), and cone-beam computed tomography (69.5%). Significant differences were observed in the learning pathway for the DRL (Fisher’s exact test, p < 0.05), satisfaction with radiation safety education (Pearson’s χ2 test = 5.3975, Pr = 0.02), and use of personnel radiation monitoring systems (Pearson’s χ 2 test = 18.1233, Pr = 0.000) between the groups. Significant differences were also observed in personnel protection using a thyroid collar and patient protection during panoramic radiography (odds ratio = 14.2). Dental hygienists with more than 10 years of experience were more satisfied with radiation safety education and more interested in radiation monitoring. Considering career experience, customized, continuous, and effective radiation safety management education should be provided.

Implications of specific gene expression patterns in enamel knot in tooth development

Enamel knot (EK)—a signaling center—refers to a transient morphological structure comprising epithelial tissue. EK is believed to regulate tooth development in early organogenesis without its own cellular alterations, including proliferation and differentiation. EKs show a very simple but conserved structure and share functions with teeth of recently evolved vertebrates, suggesting conserved signaling in certain organs, such as functional teeth, through the course of evolution. In this study, we examined the expression patterns of key EK-specific genes including Dusp26 , Fat4, Meis2, Sln , and Zpld1 during mice embryogenesis. Expression patterns of these genes may reveal putative differentiation mechanisms underlying tooth morphogenesis.

Radiographic study of dermal fillers in the facial area: A series of 3 cases

In recent years, as interest in maintaining beauty and a youthful appearance has grown, filler procedures such as soft tissue augmentation have become more popular. These fillers are sometimes seen as radiopaque shadows on radiographic images, either due to the fillers themselves or because of secondary reactions; such findings may present a diagnostic challenge to dentists. The present report describes 3 cases of dermal fillers observed in panoramic and cone-beam computed tomographic (CBCT) images. All 3 elderly female patients had filler injected into their cheeks and chin area for cosmetic purposes decades ago. On panoramic images, multiple symmetric radiopacities were observed in the facial area; on CBCT, these calcifications were seen in the subcutaneous tissue in various shapes and with varying density. In conclusion, dentists should be aware of the imaging characteristics of dermal filler, and should be able to differentiate dermal filler from other pathological findings.

Radiopacity of contemporary luting cements using conventional and digital radiography

PURPOSE: This study evaluated the radiopacity of contemporary luting cements using conventional and digital radiography. MATERIALS AND METHODS: Disc specimens (N=24, n=6 per group, ø7 mm×1 mm) were prepared using 4 resin-based luting cements (Duolink, Multilink N, Panavia F 2.0, and U-cem). The specimens were radiographed using films, a complementary metal oxide semiconductor (CMOS) sensor, and a photostimulable phosphor plate (PSP) with a 10-step aluminum step wedge (1 mm incremental steps) and a 1-mm-thick tooth cut. The settings were 70 kVp, 4 mA, and 30 cm, with an exposure time of 0.2 s for the films and 0.1 s for the CMOS sensor and PSP. The films were scanned using a scanner. The radiopacity of the luting cements and tooth was measured using a densitometer for the film and NIH ImageJ software for the images obtained from the CMOS sensor, PSP, and scanned films. The data were analyzed using the Kruskal-Wallis and Mann-Whitney U tests. RESULTS: Multilink (3.44–4.33) showed the highest radiopacity, followed by U-cem (1.81–2.88), Panavia F 2.0 (1.51–2.69), and Duolink (1.48–2.59). The R² values of the optical density of the aluminum step wedge were 0.9923 for the films, 0.9989 for the PSP, 0.9986 for the scanned films, and 0.9266 for the CMOS sensor in the linear regression models. CONCLUSION: The radiopacities of the luting materials were greater than those of aluminum or dentin at the same thickness. PSP is recommended as a detector for radiopacity measurements because of its accuracy and convenience.

Verification of a computer-aided replica technique for evaluating prosthesis adaptation using statistical agreement analysis

PURPOSE: The purpose of this study was to evaluate the reliability of computer-aided replica technique (CART) by calculating its agreement with the replica technique (RT), using statistical agreement analysis. MATERIALS AND METHODS: A prepared metal die and a metal crown were fabricated. The gap between the restoration and abutment was replicated using silicone indicator paste (n = 25). Gap measurements differed in the control (RT) and experimental (CART) groups. In the RT group, the silicone replica was manually sectioned, and the marginal and occlusal gaps were measured using a microscope. In the CART group, the gap was digitized using optical scanning and image superimposition, and the gaps were measured using a software program. The agreement between the measurement techniques was evaluated by using the 95% Bland-Altman limits of agreement and concordance correlation coefficients (CCC). The least acceptable CCC was 0.90. RESULTS: The RT and CART groups showed linear association, with a strong positive correlation in gap measurements, but without significant differences. The 95% limits of agreement between the paired gap measurements were 3.84% and 7.08% of the mean. The lower 95% confidence limits of CCC were 0.9676 and 0.9188 for the marginal and occlusal gap measurements, respectively, and the values were greater than the allowed limit. CONCLUSION: The CART is a reliable digital approach for evaluating the fit accuracy of fixed dental prostheses.

Recurrent osteochondroma of the mandibular condyle: A case report

A 21-year-old woman presented with facial asymmetry. Crepitus and clicking of the temporomandibular joint were noted. The midline deviated 5.5 mm to the left, and secondary malocclusion was observed. Panoramic and cone-beam computed tomographic images showed an irregular and exophytic bony mass on the anteromedial surface of the right mandibular condyle. A 3-phase bone scan revealed increased tracer uptake on the affected side. The lesion was treated with excision and reshaping under the diagnosis of osteochondroma confirmed by a histopathological examination. The lesion recurred after 3 years, and the patient underwent condylectomy. Mandibular condylar osteochondroma is often resected because it causes functional and aesthetic problems, but it rarely recurs. To the best of our knowledge, only 2 cases of recurrent osteochondromas of the mandibular condyle have been reported previously. Surgical treatment of the osteochondroma should be performed considering the possibility of recurrence, and long-term follow-up is recommended.

Accuracy of a direct drill-guiding system with minimal tolerance of surgical instruments used for implant surgery: a prospective clinical study

PURPOSE: A recently introduced direct drill-guiding implant surgery system features minimal tolerance of surgical instruments in the metal sleeve by using shank-modified drills and a sleeve-incorporated stereolithographic guide template. The purpose of this study was to evaluate the accuracy of this new guided surgery system in partially edentulous patients using geometric analyses. MATERIALS AND METHODS: For the study, 21 implants were placed in 11 consecutive patients using the direct drill-guiding implant surgery system. The stereolithographic surgical guide was fabricated using cone-beam computed tomography, digital scanning, computer-aided design and computer-assisted manufacturing, and additive manufacturing processes. After surgery, the positional and angular deviations between planned and placed implants were measured at the abutment level using implant-planning software. The Kruskal-Wallis test and Mann-Whitney U test were used to compare the deviations (α=.05). RESULTS: The mean horizontal deviations were 0.593 mm (SD 0.238) mesiodistally and 0.691 mm (SD 0.344) buccolingually. The mean vertical deviation was 0.925 mm (SD 0.376) occlusogingivally. The vertical deviation was significantly larger than the horizontal deviation (P=.018). The mean angular deviation was 2.024 degrees (SD 0.942) mesiodistally and 2.390 degrees (SD 1.142) buccolingually. CONCLUSION: The direct drill-guiding implant surgery system demonstrates high accuracy in placing implants. Use of the drill shank as the guiding component is an effective way for reducing tolerance.

Relationship between periodontal status and chronic obstructive pulmonary disease / 대한구강보건학회지

OBJECTIVES: The aim of this study was to examine the relationship between periodontal health and chronic obstructive pulmonary disease (COPD) in a Korean population. METHODS: The Community Periodontal Index (CPI) data of 7,264 subjects, aged over 25 years, who participated in the Fourth Korea National Health and Nutrition Examination Survey was used to assess the periodontal status of the population. Severity of COPD in the subjects was classified according to the Global Initiative for Chronic Obstructive Lung Disease (GOLD) definition. RESULTS: Subjects with more severe COPD were more likely to have severe periodontal disease. After adjustment for gender, age, monthly income, education, economic activity, and occupation, the odds ratio of COPD was 1.18 (95% Confidence interval [CI], 0.63-2.21) for severe periodontal disease in the study sample. When stratified by smoking status, the odds ratio of current smokers was 0.92 (95% CI, 0.41-2.05) and that of non-smokers was 1.29 (95% CI, 0.64-2.59). CONCLUSIONS: Periodontal health was not significantly related to the severity of the COPD, even though smoking was a common risk factor. This is the first study examining the relationship between periodontal health and COPD in a Korean population. Studies that further investigate the causal relationship between the two are recommended.

Aneurysmal bone cyst of the mandible managed by conservative surgical therapy with preoperative embolization

A 9-year-old girl visited our hospital, complaining of a rapid-growing and rigid swelling on the left posterior mandibular area. Panoramic radiograph showed a moderately defined multilocular honeycomb appearance involving the left mandibular body. CT scan revealed an expansile, multilocular osteolytic lesion and multiple fluid levels within cystic spaces. Bone scan demonstrated increased radiotracer uptake and angiography showed a highly vascularized lesion. The lesion was suspected as aneurysmal bone cyst (ABC) and preoperative embolization was performed, which minimize the extent of operation and the surgical complication. The lesion was treated by surgical curettage and lateral decortication with repositioning. No additional treatment such as a surgical reconstruction or bone graft was needed. Early diagnosis of ABC is very important and appropriate treatment should be performed considering several factors such as age, surgical complication, and possibility of recurrence.

Improved periodontal health aspects according to the tooth position through the non-surgical professional oral hygiene care in the diabetic youth / 대한구강보건학회지

OBJECTIVES: The aim of this study was to compare short-term and medium-term effects of gingival index (GI) and dental plaque index (PI), according to the tooth position through the oral hygiene education in the diabetic youth. METHODS: The total number of participants were 31 diabetics and 87 controls in the city of Daegu. Oral examination and professional oral hygiene care were performed among the 31 diabetic youth who consented to the study at the first visit. The professional oral hygiene care consisted of the tooth brushing method, oral prophylaxis, scaling, fluoride application, sealant and dental auxiliary education. We collected the data from all participants for the identification of oral condition at 2 weeks and 3 months. The #11, #14, #16, #31, #34, #36 teeth were selected for the measurement of the oral hygiene conditions. GI and PI were used for oral hygiene scores. The data was analyzed with SPSS 18.0 program. RESULTS: Both GI and PI were significantly decreased in the treatment group of the 31 diabetic youth in comparison to the controls, by tooth position compared to the baseline (P<0.001). In particular, GI measurements constantly decreased upto 3 months and the PI measurements decreased upto 2 weeks and increased slightly from 2 weeks to 3 months. In the GI measurements, the decrement of #14 was the highest (48.4%) and #36 was the lowest (25.2%) among all teeth. In the PI measurements, the decrement of #14 was the highest (45.5%) and #16 was the lowest (19.8%) among all teeth. In the control group, PI increased on all tooth positions, and GI increased on some tooth positions. CONCLUSIONS: The program of professional oral hygiene care in the diabetic youth has improved the oral health care when compared to the controls. We suggest that the sites where oral hygiene is more difficult to control have more oral hygiene education than the other sites.

Odontoma: a retrospective study of 73 cases

PURPOSE: The purpose of the present study was to retrospectively evaluate the clinical findings and treatment results for impacted permanent teeth associated with odontomas. MATERIALS AND METHODS: We retrospectively investigated 73 odontomas in 72 patients who visited Kyungpook National University Dental Hospital from April 2004 through November 2011. The study was performed using medical records, panoramic radiographs, and pathological reports. Data gathered included age, gender, location, chief complaints, effects on dentition, and treatment of odontoma and the impacted tooth associated with odontoma. RESULTS: Most compound odontomas (46.7%) were found in the second decade and complex odontomas were not related to age. Odontomas showed no gender predilection. Fifty-five cases (75.3%) of odontomas were detected on routine dental radiographs. Sixty percent of compound odontomas occurred in the canine area and 57.1% of complex odontomas in the molar areas. Impaction of permanent teeth (61.6%) was the most common complication on the adjacent teeth. Most odontomas (84.9%) were removed surgically and impacted permanent teeth were managed by surgical removal (53.2%), orthodontic treatment (25.5%), or surgical repositioning (6.4%). There was a statistically significant relation between age and preservation of the impacted permanent teeth associated with odontomas (p<0.01). CONCLUSION: Early detection and treatment of odontomas increase the possibility of preservation of the impacted tooth. Therefore, it would be suggested that periodic panoramic examination during the first and second decade of life might be beneficial for the early detection and better prognosis of odontomas.

Comparison of mRNA expression of gtf genes and adhesive ability of xylitol-sensitive and -resistant Streptococcus mutans by xylitol-treated concentrations / 대한구강보건학회지

OBJECTIVES: Xylitol is an effective anticarious natural sugar substitute, by inhibiting the virulence of Streptococcus mutans (S. mutans). However, long-term xylitol consumption leads to an emergence of the xylitol-resistant (XR) strains. This study aimed to confirm the general characteristics, mRNA expression of gtf genes, and adhesive ability of the xylitol-sensitive (XS) and XR S. mutans , by xylitol-treated concentrations. METHODS: S. mutans KCTC3065 was maintained in TYE medium, containing 0.4% glucose with 1% xylitol for 30 days at 37degrees C, 10% CO2 to form XR strain and the same procedures, without xylitol, were repeated for the formation of XS S. mutans. Both XS and XR were cultured by xylitol-treated concentrations (0%, 0.1% and 1%), then, general characteristics, such as growth and acid production, mRNA expression of gtf genes and adhesive ability were analyzed. RESULTS: Xylitol reduced the cell growth of XS S. mutans in a dose-dependent manner, but did not reduce the XR. Xylitol inhibited acid production of XS in a dose-dependent manner. However, it did not inhibit that of XR. Xylitol reduced the gtfB and gtfD mRNA expression of the XS S. mutans, which the genes synthesized soluble and insoluble extracellular polysaccharides, but not reduced that of the XR. By a microtiter plate assay, biofilm formation was more reduced in the XR strains, which means biofilm's adhesive ability of XR S. mutans was lower than that of the XS. CONCLUSIONS: These results indicate that a lower level of adhesive ability for XR S. mutans is related with mRNA expression level of gtf genes, which suggested that the XR strains may be less cariogenic than that of the XS.

Simple bone cysts of two brothers / 대한구강악안면방사선학회지

17-year-old and 14-year-old brothers were referred for evaluation of the cystic lesions on the mandibular anterior area with no symptoms. Neither their mother nor the brothers could recall any past trauma to those areas. Panoramic and intraoral radiographs revealed moderately defined cystic lesions on their mandibular anterior areas. Biopsies on both lesions revealed simple bone cysts. Hereditary cause or familial history of simple bone cysts could not be found in literature review. This case may have been a coincidence. However, further investigation is needed to find the cause of simple bone cysts occurring in patients those are closely related.

Efficacy of panoramic radiography as a screening procedure in dental examination compared with clinical evaluation / 대한구강악안면방사선학회지

PURPOSE: To evaluate the efficacy of panoramic radiography by comparing the results of clinical examination with radiographic findings. MATERIALS AND METHODS: We studied 190 patients (20 men and 170 women; mean age, 40 years; range, 22 to 68 years) who visited the health promotion center of Korea Medical Science Institute and were examined both clinically and by panoramic radiography. We compared results from both examinations. Treatment options by clinical examination were described as "no treatment indicated", "treatment of dental caries", "removal of calculus", "treatment of periodontal disease", "prothodontic treatment" and "extraction of the third molar". Findings taken from the panoramic radiography were: dental caries, periapical lesion, alveolar bone loss, calculus deposition, retained root, impaction of the third molar, disease of maxillary sinus, bony change of mandibular condyle, etc. RESULTS: The prevalence of panoramic findings were: 37.9% of dental caries, 17.4% of periapical lesions, 44.7% of alveolar bone losses, 62.6% of calculi deposition, 7.9% of retained roots, 26.8% of third molar impactions, 6.3% of diseases of maxillary sinus, 2.1% of bony changes of mandibular condlye and 35.8% of miscellaneous lesions. Abnormal conditions revealed by panoramic radiography which had not been discovered on clinical examination were: 24.2% of the patients had dental caries, 17.4% had periapical lesions, 7.4% had calculi deposition, 5.3% had retained roots, 15.3% had third molar impactions. The opposite cases were: 5.2% had dental caries, 12.6% had calculi deposition, and 9.5% had third molar impactions. CONCLUSION: The use of panoramic radiography as a supplement to the clinical examination might be a valuable screening technique.

Efficacy of panoramic radiography as a screening procedure in dental examination compared with clinical evaluation / 대한구강악안면방사선학회지

PURPOSE: To evaluate the efficacy of panoramic radiography by comparing the results of clinical examination with radiographic findings. MATERIALS AND METHODS: We studied 190 patients (20 men and 170 women; mean age, 40 years; range, 22 to 68 years) who visited the health promotion center of Korea Medical Science Institute and were examined both clinically and by panoramic radiography. We compared results from both examinations. Treatment options by clinical examination were described as "no treatment indicated", "treatment of dental caries", "removal of calculus", "treatment of periodontal disease", "prothodontic treatment" and "extraction of the third molar". Findings taken from the panoramic radiography were: dental caries, periapical lesion, alveolar bone loss, calculus deposition, retained root, impaction of the third molar, disease of maxillary sinus, bony change of mandibular condyle, etc. RESULTS: The prevalence of panoramic findings were: 37.9% of dental caries, 17.4% of periapical lesions, 44.7% of alveolar bone losses, 62.6% of calculi deposition, 7.9% of retained roots, 26.8% of third molar impactions, 6.3% of diseases of maxillary sinus, 2.1% of bony changes of mandibular condlye and 35.8% of miscellaneous lesions. Abnormal conditions revealed by panoramic radiography which had not been discovered on clinical examination were: 24.2% of the patients had dental caries, 17.4% had periapical lesions, 7.4% had calculi deposition, 5.3% had retained roots, 15.3% had third molar impactions. The opposite cases were: 5.2% had dental caries, 12.6% had calculi deposition, and 9.5% had third molar impactions. CONCLUSION: The use of panoramic radiography as a supplement to the clinical examination might be a valuable screening technique.

Giant osteoma of the mandible causing breathing problem / 대한구강악안면방사선학회지

The review of the literature determines that large osteomas of the mandible are relatively rare. We present a case of a 60-year-old man with painless swelling of the left submandibular area and mild difficulty in breathing. The patient complained that the mass have been progressing slowly for at least 20 years. Radiographic studies showed a giant osteoma that attached to the lingual surface of the left mandibular angle and extended from submandibular space to infratemporal space. After the excision of the tumor the patient made a full recovery.