Showing papers in "The Chinese journal of dental research : the official journal of the Scientific Section of the Chinese Stomatological Association in 2017"

The New Definition of Oral Health and Relationship between Oral Health and Quality of Life.

Abstract: FDI World Dental Federation, which has 200 dental association members in some 130 countries, is the official representative body and voice of more than 1 million clinicians worldwide. It set itself the task of creating a new definition for oral health as a baseline to develop tools to measure oral health and related indicators. The definition allows FDI to position oral health within the global health agenda in areas such as quality of life and wellbeing and the challenge of an ageing population worldwide. Furthermore, it provides an impetus for FDI activities in favour of worldwide periodontal health.

Salivary IgA, Interleukin-1β and MMP-8 as Salivary Biomarkers in Chronic Periodontitis Patients.

Abstract: Objective To compare the clinical parameters and levels of salivary immunoglobulin A (IgA), Interleukin-1β (IL-1β) and matrix metalloproteinase-8 (MMP-8) in patients with moderate to severe chronic periodontitis and in individuals with healthy gingiva. Methods Levels of clinical parameters plaque index (PI), gingival index (GI), probing depth (PD), clinical attachment level (CAL) and bleeding on probing (BOP) along with salivary biomarkers salivary IgA, IL-1β and MMP-8 were recorded among 50 adults (30 test subjects with moderate to severe generalised chronic periodontitis, constituting group A, and 20 periodontally healthy controls - group B). Clinical evaluation was done before oral prophylaxis, and 6 weeks and 12 weeks after oral prophylaxis, and saliva samples were obtained before and 12 weeks after oral prophylaxis. Salivary IgA, IL-1β and MMP-8 levels in saliva were assessed using enzyme-linked immunosorbent assay. Results In group A, there were highly significant differences in terms of PI, GI, PD, CAL and BOP before oral prophylaxis, and 6 weeks and 12 weeks after oral prophylaxis when compared at these intervals. Differences in their levels in group B were non-significant at such intervals except PI. Mean levels of salivary IgA, IL-1β and MMP-8 in chronic periodontitis patients at baseline were significantly higher than in the periodontally healthy group. Their levels in group A decreased significantly 12 weeks after oral prophylaxis, but remained static in group B. Conclusion The levels of salivary IgA, IL-1β and MMP-8 showed significant reduction after oral prophylaxis, suggesting that these biomarkers could facilitate the screening, early diagnosis, and management of periodontal disease.

Risk Factors associated with Early Childhood Caries.

Abstract: Objective To analyse factors associated with the susceptibility of early childhood caries (ECC), populations with a high risk of ECC were screened and guidance for ECC prevention was proposed. Methods A total of 392 children aged 24 to 71 months were selected for oral examination in Qingdao. Parents or guardians of the participants completed the questionnaires and decayed missing filled surface (dmfs) were recorded. Differences in caries condition and oral health behaviour in different families were compared. Risk factors related to ECC were screened. The subjects were finally grouped based on the obtained dmfs into three groups: caries-free, ECC and S-ECC (severe ECC). Association of risk factors with the caries status was analysed using the Kruskal-Wallis test, the chi-square test and logistic regression analysis. Results There were significant differences among the caries-free, ECC and S-ECC groups in three parameters: eating too many sweets each day, brushing before and after sleeping, and whether parents helped to brush (P 0.05). Conclusion Eating a lot of sweets, an incorrect brushing method, starting brushing at a later stage and not brushing regularly are susceptible factors for ECC. Emphasising oral health knowledge to parents and guardians, conducting proper brushing methods, limiting the frequency of sweets being eaten and avoiding an inappropriate habit of eating sweets are very important factors in the prevention of ECC.

Trend Analysis of Betel Nut-associated Oral Cancer and Health Burden in China.

Abstract: Objective To forecast the future trend of betel nut-associated oral cancer and the resulting burden on health based on historical oral cancer patient data in Hunan province, China Methods Oral cancer patient data in five hospitals in Changsha (the capital city of Hunan province) were collected for the past 12 years Three methods were used to analyse the data; Microsoft Excel Forecast Sheet, Excel Trendline, and the Logistic growth model A combination of these three methods was used to forecast the future trend of betel nut-associated oral cancer and the resulting burden on health Results Betel nut-associated oral cancer cases have been increasing rapidly in the past 12 years in Changsha As of 2016, betel nuts had caused 8,222 cases of oral cancer in Changsha and close to 25,000 cases in Hunan, resulting in about ¥5 billion in accumulated financial loss The combined trend analysis predicts that by 2030, betel nuts will cause more than 100,000 cases of oral cancer in Changsha and more than 300,000 cases in Hunan, and more than ¥64 billion in accumulated financial loss in medical expenses Conclusion The trend analysis of oral cancer patient data predicts that the growing betel nut industry in Hunan province will cause a humanitarian catastrophe with massive loss of human life and national resources To prevent this catastrophe, China should ban betel nuts and provide early oral cancer screening for betel nut consumers as soon as possible

Mechanical Properties and Wear of Five Commercial Fibre-Reinforced Filling Materials.

Abstract: OBJECTIVE To evaluate and compare certain mechanical properties and wear of five commercial short-fibre reinforced composites (Alert, EasyCore, Build-It, TI-Core, and everX Posterior), in relation to their microstructural characteristics. METHODS Fracture toughness, work of fracture, and flexural strength were determined for each material following ISO standards. The specimens (n = 6) were dry stored (37 °C for 2 days) before they were tested. A wear test was conducted with 15,000 chewing cycles using a dual-axis chewing simulator. Wear pattern was analysed by a three-dimensional (3D) noncontact optical profilometer. Scanning electron microscopy (SEM) was used to evaluate the microstructure of each composite material. The results were statistically analysed using ANOVA followed by post hoc Tukey's test. RESULTS everX Posterior exhibited the highest fracture toughness (2.4 MPa m1/2) among the materials tested (P 0.05) from Alert (119 MPa) and everX Posterior (120 MPa). Lowest wear values were found for EasyCore and Build-It (19 and 22 µm). TI-Core showed significantly higher wear depth (45 µm) than all other materials (P < 0.05). CONCLUSION Significant differences between commercial short-fibre reinforced composites were found for fracture toughness and wear.

Quantity of Candida Colonies in Saliva: A Diagnostic Evaluation for Oral Candidiasis.

Abstract: OBJECTIVE To investigate the relationship between the quantity of Candida colonies in saliva and oral candidiasis (OC), as well as to identify the threshold for distinguishing oral candidiasis from healthy carriage. METHODS A diagnostic test was conducted in 197 patients with different oral problems. The diagnosis of OC was established based on clinical features. Whole saliva samples from the subjects were cultured for Candida species. Receiver operating characteristic (ROC) curve analysis was used in this study. RESULTS OC patients had significantly more Candida colony-forming units per millilitre saliva (795 cfu/ml) than asymptomatic carriers (40 cfu/ml; P < 0.05). Among different types of candidiasis, the quantity of Candida colonies differed. The number of Candida colonies in pseudomembranous type was significantly higher than that in the erythematous type (P < 0.05). Candida albicans was the predominant species of Candida. The cut-off point with the best fit for OC diagnosis was calculated to be 266 cfu/ml. The sensitivity and specificity were 0.720 and 0.825, respectively. Analysis of the ROC curve indicated that Candida colonies had a high diagnostic value for OC, as demonstrated by the area under the curve (AUC = 0.873). CONCLUSION Based on this study, the value of 270 cfu/ml was considered a threshold for distinguishing OC from carriage.

Teeth under High Occlusal Force may Reflect Occlusal Trauma-associated Periodontal Conditions in Subjects with Untreated Chronic Periodontitis.

Abstract: OBJECTIVE To determine the association of high occlusal force (HOF) with the signs of occlusal trauma and periodontal conditions in periodontitis patients, and elaborate the relevant clinical implications. METHODS Periodontal parameters and signs of occlusal trauma were recorded for 807 teeth in 30 subjects with untreated chronic periodontitis. The T-scan II occlusal analysis system determined the HOF during maximum intercuspation, lateral excursion and protrusive excursion. The correlation of HOF with periodontal parameters and signs of occlusal trauma was analysed. RESULTS Overall, the teeth with HOF existed mainly in molars and presented with deeper probing depth (PD) and higher frequency of bleeding on probing (BOP) than those without HOF. The fixed-effect analysis showed that HOF was positively correlated with PD and BOP (P < 0.05) in posterior teeth; widened periodontal ligament space on radiographs in upper (r = 0.179, P < 0.01) and lower posterior teeth (r = 0.205; P < 0.05); as well as functional mobility in upper posterior teeth (r = 0.168; P < 0.05). CONCLUSION This study suggests that the posterior teeth with HOF in subjects with chronic periodontitis may reflect occlusal trauma-associated periodontal conditions that could probably increase the risk of further periodontal destruction. These findings may improve the clinical assessment of occlusal trauma and related periodontal conditions for better patient management and treatment outcomes.

Minimally Invasive Crestal Sinus Lift Technique and Simultaneous Implant Placement.

Abstract: OBJECTIVE To evaluate the effectiveness and clinical results of a new crestal sinus lift technique used to elevate the sinus floor simultaneously with bone grafts and implant placement. METHODS Eleven patients underwent this crestal sinus lift technique performed using an SCA KIT. The mean residual bone height was 6.4 mm (range: 4.1 mm to 8.6 mm). Bio-Oss collagen was used as the graft material, and 12 implants were simultaneously placed after sinus augmentation. Radiographic and clinical examinations were conducted during follow-up. RESULTS All procedures were successfully performed with no obvious Schneiderian membrane perforation. The sinus floor was augmented with a mean height of 4.8 mm (range: 2.8 to 7.4 mm). Twelve implants healed uneventfully with healing abutments. Peri-implant marginal bone was stable, with a mean follow-up of 49.4 months (range: 33 to 71 months). No complications were observed during follow-up. CONCLUSION According to the limited data collected in this study, the novel crestal sinus lift approach could effectively lift the sinus floor and reduce the incidence of postoperative complications. Additional cases with long-term follow-up are needed to confirm and improve this crestal sinus lift technique.

Subgingival Microbiome of Gingivitis in Chinese Undergraduates.

Abstract: Objective To analyse the microbiome composition of health and gingivitis in Chinese undergraduates with high-throughput sequencing. Methods Sequencing of 16S rRNA gene amplicons was performed with the MiSeq system to compare subgingival bacterial communities from 54 subjects with gingivitis and 12 periodontally healthy controls. Results A total of 1,967,372 sequences representing 14 phyla, 104 genera, and 96 species were detected. Analysis of similarities (Anosim) test and Principal Component Analysis (PCA) showed significantly different community profiles between the health control and the subjects with gingivitis. Alpha-diversity metrics were significantly higher in the subgingival plaque of the subjects with gingivitis compared with that of the healthy control. Overall, the relative abundance of 35 genera and 46 species were significantly different between the two groups, among them 28 genera and 45 species showed higher relative abundance in the subjects with gingivitis, whereas seven genera and one species showed a higher relative abundance in the healthy control. The genera Porphyromonas, Treponema, and Tannerella showed higher relative abundance in the subjects with gingivitis, while the genera Capnocytophaga showed higher proportions in health controls. Porphyromonas gingivalis, Prevotella intermedia and Porphyromonas endodontalis had higher relative abundance in gingivitis. Among them, Porphyromonas gingivalis was most abundant. Conclusion Our results revealed significantly different microbial community composition and structures of subgingival plaque between subjects with gingivitis and healthy controls. Subjects with gingivitis showed greater taxonomic diversity compared with periodontally healthy subjects. The proportion of Porphyromonas, especially Porphyromonas gingivalis, may be associated with gingivitis subjects aged between 18 and 21 years old in China. Adults with gingivitis in this age group may have a higher risk of developing periodontitis.

Association between EDAR Polymorphisms and Non-Syndromic Tooth Agenesis in the Chinese Han Population.

Abstract: Objective To explore the relationship between single nuclear polymorphisms (SNPs) in ectodysplasin A receptor (EDAR) and EDAR-associated death domain (EDARADD) genes and non-syndromic tooth agenesis. Methods Ten putative SNPs in EDAR and EDARADD were selected, and a case-control study was conducted in 112 subjects with non-syndromic tooth agenesis and 112 normal control subjects. DNA was obtained from peripheral blood samples. Genotyping was performed by Sanger sequencing. Results Three SNPs (rs3749098, rs3749099, and rs10432616) in EDAR exhibited significant differences in the alleles and/or genotype frequencies between the case group (individuals with non-syndromic tooth agenesis) and control group (normal individuals). The T allele was identified in the SNP rs3749098 in 99.1% of the case group and in 96.0% of the control group (P = 0.0326). Regarding the SNP rs3749099, the C allele was identified in 99.1% of the case group and in 96.0% of the control group (P = 0.0326). Regarding the SNP rs10432616, the C allele was identified in 97.8% of the case group and in 100.0% of the control group (P = 0.0245). Conclusion Our results suggested that SNPs in EDAR could be a pathogenic factor for non-syndromic tooth agenesis. Furthermore, EDAR can be regarded as a marker gene for the risk of tooth agenesis.

A Review of Excessive Sugar Metabolism on Oral and General Health.

Abstract: Stomatologists and dental practitioners, as they are called in different parts of the world according to tradition and history, are basically physicians who specialise in the study and treatment of diseases of the mouth and surrounding structures. They have always been outstanding in advocating the reduction of sugar consumption, mainly due to its direct connection to the pathogenesis of dental caries. Increasingly, it has come to the attention of researchers, epidemiologists and many healthcare workers and professionals that excessive consumption of sugar is also closely tied to the increase in tandem of our current major health issues like obesity, diabetes, heart, liver and kidney disease, and a host of other associated ailments. This development of current health crises throughout the world wherever traditional diets are replaced with modern fast food diets, which are usually packed with hidden, added refined sugars, is extremely troubling. It becomes all the more urgent and incumbent upon clinicians and stomatologists throughout the world to redouble their efforts to reduce and even eliminate the excessive consumption of added or extrinsic or secondary or hidden sugars to food and drinks. It will not only be to reduce dental caries, but also to reduce the many systemic and organ diseases associated with added sugars and which also exacerbate many oral diseases. This review is to give a basic history of sugar, the current understanding of sugar metabolism and the developing literature and research on the impact of sugar consumption on oral and overall health, as the mouth cannot be divorced from the body and vice versa. The author hopes to kick-start more research into this area that will result in various positive developments in the food and drink industry and persuade stakeholders to comprehensively address this universal health crisis that is closely tied to excessive consumption of added sugar in all its forms.

Comparison of Real-Time Quantitative PCR with a Chairside Test for Streptococcus Mutans Assessment.

Abstract: Objective To compare two methods for Streptococcus mutans detection and quantification in the human oral cavity: a chairside commercial test and a molecular-based real-time quantitative polymerase chain reaction (qPCR) method. Methods A total of 688 whole saliva samples were collected from 344 children aged 3 and 5 and their biological mothers. Caries status was examined using a World Health Organisation survey method. S. mutans levels were measured using the Dentocult SM Strip mutans test and scored as colony forming units per millilitre of saliva. Meanwhile, bacterial genomic DNA was extracted from the saliva, qPCR was performed with S. mutans species-specific primers, and absolute S. mutans DNA concentrations were obtained and scored as micrograms of DNA per millilitre of saliva. The two methods were compared for sensitivity, specificity, agreement and correlation with caries status. Results Significantly more participants tested positive for S. mutans by qPCR than in the chairside SM Strip test (82.4% vs 71.4%). When only the highest and lowest test scores were considered, the agreement between the two methods assessing S. mutans colonisation was 0.956. Children with high levels of S. mutans in their saliva were six to eight times more likely to develop dental caries at 5 years old. Conclusion The study provides new evidence supporting the use of the chairside SM Strip test or the qPCR assay for the detection and quantification of S. mutans colonisation in saliva as the analytical approach of choice for caries risk assessment in clinical and epidemiological studies.

Effect of Chlorhexidine and Ethanol on Microleakage of Composite Resin Restoration to Dentine

Abstract: Objective To evaluate the effect of chlorhexidine and ethanol on microleakage of composite resin restoration to dentine. Methods Class II cavities with dentinal margin were prepared on 96 premolar teeth. All specimens were acid-etched, rinsed and dried. Then the samples were randomly divided into four groups according to pre-treatment of the dentine: no treatment (control group); treatment with 100% ethanol for 60 s (group 2); treatment with 2% chlorhexidine for 60 s (group 3); 100% ethanol for 60 s and then 2% chlorhexidine for 60 s (group 4). After dentine treatment, each group was bonded and restored with a universal micro hybrid composite resin, according to the manufacturers' recommendation. Microleakage was evaluated by dye extraction method in two subgroups, immediately (24 h) and after 6 months in storage. Scan electronic microscope analyses for two samples of each group were also conducted. Data were analysed by two-way analysis of variance and Tukey test. Results The lowest and the highest amount of microleakage were observed in the ethanol group and in the control group, respectively. There were significant differences in microleakage among the groups (P = 0.003) and between measurement times (P = 0.001). For each storage time, the control group showed significant differences from the other groups and there were no differences between the other groups. Conclusion Ethanol-wet bonding and chlorhexidine application may have potential benefits in lowering the occurrence of microleakage in the long term.

Proposing a Novel, Three-level Definition of Periodontitis using Probing Depth, Clinical Attachment Loss and Bleeding on Probing: Analysis of a Rural Chinese Population.

Abstract: Objective To propose a novel, three-level (severe, moderate, mild) case definition using probing depth (PD), clinical attachment loss (CAL) and bleeding on probing (BOP) for epidemiologic studies on periodontitis. Methods Case definitions (DEF) 1-30 with PD, CAL and BOP were made. Based on data from epidemiologic research in Chengde (Hebei Province, China) in 1992, prevalence of periodontitis by DEF1-30 was calculated and compared with a reference (definitions by Centers for Disease Control and Prevention/American Academy of Periodontology in 2012). Sensitivity, specificity, Youden Index, Cohen's kappa coefficient (CKC) and the area under the receiver operator characteristic curve (AUC) were calculated for the definitions selected. Results DEF1 and DEF18 for periodontitis, DEF2, DEF3, DEF19 for moderate and severe periodontitis, and DEF5, DEF13, DEF14, DEF21 and DEF25 for severe periodontitis, which were similar for estimation of periodontitis prevalence compared with the reference, were selected. DEF18 for periodontitis, DEF19 for moderate and severe periodontitis, and DEF5 for severe periodontitis were selected because they showed higher values for the Youden Index, CKC and AUC, and formed a three-level definition. Conclusion A novel three-level case classification of periodontitis using three parameters of PD, CAL and BOP was proposed. The estimated periodontitis prevalence according to the novel proposed definition is close to the prevalence according to the CDC/AAP definition.

Effects of Combining Insulin-like Growth Factor 1 and Platelet-derived Growth Factor on Osteogenesis around Dental Implants

Abstract: Objective To explore the effects of the combination of insulin-like growth factor 1 (IGF-1) and platelet-derived growth factor (PDGF) on bone formation around dental implants. Methods A total of 24 adult rabbits were included in this experiment. Titanium machine-polished dental implants were placed in the iliac bones to simulate dental implants in the alveolar bone. The rabbits were randomly divided into four groups; a saline treated control group (NS), an IGF-1 treated group, a PDGF-BB treated group, and a combination of IGF-1 and PDGF-BB treated group. The rabbits were sacrificed after 3, 7, and 10 days, and implants and soft tissues around implants were histologically evaluated. Results All of the rabbits began to recover their appetite, move freely and the operation area started detumescence until after the fourth day. HE while in combination, earlier collagen fibre hyperplasia appeared.

Virtual Simulation Teaching Centre in Dental Education: a Report from Fujian Medical University, China.

Abstract: This report gives a brief introduction to the Virtual Simulation Teaching Centre of Fujian Medical University School of Stomatology (VSFMUSS), China. As one of the best dental simulation laboratories in China, the VSFMUSS aims to train dental students and clinicians to be professionals who are able to provide optimal oral health care by giving them the best virtual patient care experience possible in a nonclinical setting. The features, achievements and future directions of the VSFMUSS are addressed. Moreover, the role of the VSFMUSS was evaluated and discussed based on the students' and faculties' perceptions, rate of employment after graduation, and so on.

Improvement of Implant Placement after Bone Augmentation of Severely Resorbed Maxillary Sinuses with 'Tent-Pole' Grafting Technique in Combination with rhBMP-2.

Abstract: Objective To study the clinical effect of short implant placement using osteotome sinus floor elevation technique and tent-pole grafting technique with recombinant human bone morphogenetic protein 2 (rhBMP-2) in severely resorbed maxillary area. Methods Eleven patients with insufficient bone height in the posterior maxillary area were included. According to the native bone height and crown height space (CHS), the patients were divided into two groups: immediate placement of short implants with simultaneous bone augmentation (group A, 5 patients) and delayed dental implant placement (4 to 6 months) after bone augmentation. The rhBMP-2 was added into a deproteinised bovine bone mineral (DBBM) bone grafting material to shorten the treatment procedure and enhance the final effect of bone augmentation in both groups. Tent-pole grafting technique was applied for vertical bone augmentation in group B (6 patients). Results The success rate of the implants placed was 100% in both groups. In group A, the short implants treatment was successful, with a vertical gain of 1.5 to 6.4 mm in bone height after 4 to 6 months. In group B, the tent-pole grafting procedure in combination with DBBM and rhBMP-2 increased vertical bone height between 3.1 and 8.1 mm, an optimistic and adequate increase for implant placement. This bone increase was maintained following implant placement and final crown placement in the maxillary region (3.5 to 7.3 mm). Conclusion The tent-pole grafting technique was a viable alternative choice to lateral sinus floor elevation in cases with excessive CHS. The application of rhBMP-2 with a shortened treatment time demonstrated positive outcomes in sinus floor augmentation procedures.

A Rare Case of Two Accessory Maxillae with Bilateral Tessier 7 clefts.

Abstract: A 10-year-old Chinese girl with two accessory maxillae and bilateral Tessier no. 7 clefts is presented. Radiographic examination showed two accessory maxillae, each containing 5 or 6 supernumerary permanent teeth. The two accessory maxillae extended from the inside of the zygomatic arch to the maxillary tuberosity symmetrically. Duplication of the maxilla is always associated with Amniotic Band Syndrome (ABS), but this case may be a distinct syndrome representing an under-recognised phenotype with bilateral maxillae duplication and Tessier no. 7 clefts.

Psychological Stress Alters Extracellular Matrix Metabolism in Mandibular Condylar Cartilage.

Abstract: Objective To explore the effect of long-term stress on the temporomandibular joint (TMJ) condyle and its possible underlying mechanism. Methods A 12-week, chronic unpredictable mild stress (CUMS) model was used to induce long-term psychological stress in rats. Rats were randomly divided into control group (CONT), chronic unpredictable mild stress group (CUMS) and chronic unpredictable mild stress with fluoxetine treatment group (CUMS + DT) (n = 30 per group). A 5 mg/kg dose of fluoxetine was intraperitoneally injected daily 0.5 h before stress. A sucrose preference test, plasma corticosterone test and open-field test were performed to verify the feasibility of the CUMS model. Histopathology was used to observe the pathological changes of condyle. The expression levels of inflammatory cytokines, matrix metalloproteases (MMPs) and extracellular matrix (ECM) were measured by real-time polymerase chain reaction, western blotting and immunohistochemistry. Results At 8 and 12 weeks after exposure to CUMS, the rats showed higher plasma corticosterone than the control rats. Additionally, for the open-field test, the rats exposed to CUMS spent more time in the centre zone and moved a shorter distance than the control and drug treatment rats. In addition, pathological changes in the condylar cartilage occurred in the 8-week CUMS subgroup and were more obvious in the 12-week CUMS subgroup. The CUMS caused an increase in the secretion of inflammatory cytokines, imbalanced expression of MMPs and tissue inhibitor of metalloproteinase-1 and accelerated degradation of ECM in condylar cartilage in a time-dependent manner. Conclusion Osteoarthritis-like lesions can be caused by long-term CUMS in the mandibular condyles, which suggests that the imbalance in chondrocyte-secreted regulatory factors within the cartilage of the TMJ may play an important role in cartilage injury induced by psychological stress.

Osteosarcoma of the Mandible: a Case Report with CT, MRI and Scintigraphy.

Abstract: Osteosarcomas are especially rare in the mandible and maxilla, representing 1.6% of all bony malignant tumours. In this article, we described a case of osteosarcoma of the mandible. Computed tomography (CT) image showed a well-circumscribed homogeneous mass, with nonhomogeneous contrast enhancement. T1-weighted magnetic resonance imaging (MR) image showed intermediate signal intensity on, and after administration the lesion showed signal intensity lower than muscle. T2-weighted MR image showed heterogeneous high signal intensity. Bone scintigraphy revealed monostatic involvement of the mandible with a homogenous intense uptake pattern. Ga-67 citrate scintigraphy revealed significantly increased uptake. Histopathological examination confirmed the diagnosis of osteosarcoma.

Gallium-67 Scintigraphy in Differential Diagnosis of Malignant Tumours from Non-Tumorous Lesions of the Maxilla.

Abstract: OBJECTIVE To assess the gallium-67 (67Ga) scintigraphy in differential diagnosis of malignant tumours from non-tumorous lesions of the maxilla. METHODS Nineteen patients with malignant tumours (six cases of squamous cell carcinoma and one case of malignant melanoma) and non-tumorous lesions (seven cases of maxillary sinusitis and five cases of postoperative maxillary changes) in the maxilla underwent 67Ga and bone scintigraphy with CT and MRI. The statistical analysis with respect to comparison between imaging features of 67Ga and bone scintigraphy and maxillary lesions was performed with the Pearson's chi-squared test. RESULTS 67Ga scintigraphy for six of the seven patients with malignant tumours in the maxilla was positive (85.7%), 0 of 12 patients with non-tumorous lesions were positive (0%) (P = 0.000). Bone scintigraphy for six out of seven patients with malignant tumours was positive (85.7%), 10 of 12 patients with non-tumorous lesions were positive (83.3%) (P = 0.891). CONCLUSION 67Ga scintigraphy was useful for detection of malignant tumours in the maxilla. However, bone scintigraphy was not an effective technique for interpretation of malignant tumours, maxillary sinusitis and postoperative change in the maxilla.

Comparison of Cephalometric Hard and Soft Tissues of Adolescents with Angle Class II Division 1 Malocclusion between Northern Chinese Population and Northern Indian Population.

Abstract: Objective To determine if there was a difference in hard and soft tissue between northern Chinese and northern Indian adolescents with Angle Class II division 1 malocclusion. Method A total of 40 Angle Class II division 1 patients, including 20 boys and 20 girls aged 10 to 13 years with no prior treatment, were selected from northern China and northern India, respectively. Overall, 80 cephalometric data were analysed based on two-sample t-test with SPSS software. Results The Chinese subjects had larger anterior facial height and mandibular plane angle. Analysis of dentoalveolar complex showed that the Chinese subjects had more proclined incisors, protruding upper lips and more upper posterior tooth height than that of the Indian subjects. The length of the maxilla and mandible was larger in the Indian subjects than that of the Chinese subjects, but the length of mandible was not significantly different between the two groups. Conclusion Compared with the Indian subjects, the Chinese subjects with Class II division 1 malocclusion had less prognathic maxillas, more protruding lips, steeper mandibular plane angles and more proclined maxillary incisors. Within the same gender, the Indian boys had more protruded faces and Indian girls had more protruded maxillas, steeper mandibular plane angles and fuller lips.

Development of Oral Health Impacts on Daily Living Questionnaire Items - a Qualitative Study.

Abstract: Objective To develop an instrument to measure Oral Health-related Quality of Life (OHQoL) and the changes after dental treatment among older adults in Hong Kong, in order to understand their views on the influences of oral health problems and generate relevant items to design the instrument. Methods A qualitative study was conducted among adults aged 55 and over. Information on their perceived oral health impacts was collected during semi-structured interviews. A framework approach was used to identify the oral health impacts and to understand the meaning of those impacts on the perception of life satisfaction. Results A total of 39 participants (average age 72 years) underwent the semi-structured interviews; 20 were seeking dental treatment and 19 had already received dental treatment for 1 to 3 months. In total, 308 statements on oral health impacts were drawn from the participants' descriptions. After four steps of item reduction and refinement, a list of 20 items was generated before being classified into eight domains: Cleansing, Eating, Speaking, Appearance, Social, Psychological, Awareness, and Health and Finance. Conclusion Older adults in Hong Kong perceive that oral health impacts on different aspects of life. The face validity and content validity of the developed Oral Health Impact on Daily Living (OHIDL) was proved through qualitative study.

A Rare Case of Malignant Melanoma of the Mandible: CT and MRI Findings.

Abstract: Malignant melanoma of the mandibular gingiva is extremely rare. It is a malignant tumour of melanocytes or their precursor cells, and often misinterpreted as a benign pigmented process. A few reports have described computed tomography (CT) and magnetic resonance imaging (MRI) findings of malignant melanoma in the oral cavity. We report a rare case of malignant melanoma of the mandible and the related CT and MRI findings. Soft tissue algorithm contrast-enhanced CT showed an expansile mass and irregular destruction of alveolar bone in the right side of the mandibular molar area. MR images showed an enhancing mass and the tumour had a low to intermediate signal intensity and a high-signal intensity. Soft tissue algorithm contrast-enhanced CT and MR images showed lymphadenopathy involving the submandibular lymph nodes. Histopathological examination confirmed the diagnosis of malignant melanoma.

Electrode Placing Sites affect Pulp Vitality Test of Human Incisors and Premolars.

Abstract: Objective To investigate electric pulp test thresholds at different sites on healthy incisors and premolars and determine appropriate test sites. Methods Overall, 47 volunteers aged 20 to 30 years were recruited, and 163 incisors and 140 premolars were tested at several sites with an Electric Pulp Tester. One-way analysis of variance and a Tukey test were used to analyse the threshold values among different tooth types and sites. Results The lowest threshold value for incisors was identified on the incisal edge. The difference of threshold on the incisal edge and other sites was statistically significant in mandibular incisors. For maxillary premolars and the mandibular second premolar, the lowest response was obtained with the tester tip on the lingual slope of the buccal cusp. For the mandibular first premolar, the response at the lingual slope of the buccal cusp, as the second lowest, was slightly higher than that at the buccal cusp. Conclusion The incisal edge for incisors and the lingual slope of the buccal cusp for premolars was favoured as the optimal sites for electric pulp test.

Platelet-Rich Fibrin with Bone Grafts for Regeneration of Bony Defect following Extraction of Supernumerary Teeth: A Case Report.

Abstract: Supernumerary teeth are hyperdontic variants due to abnormalities during tooth development. Here, we report a case on regeneration of bony defect, which ensued following extraction of two supernumerary teeth in the mandibular premolar region, using a combination of bone grafts and platelet-rich fibrin. To the best of our knowledge, it is the first time synergistic use of biomaterials with bone grafts have been used for this type of management.