Which characteristics can be expected from p16+-squamous cell carcinomas of the posterior oral cavity and oropharynx? - Distinctive results from Central Germany.

PURPOSE: Human papillomaviruses (HPV) link to a subset of head and neck squamous cell carcinomas (HNSCC). Our aim was to identify clinicopathological characteristics (CPC) of squamous cell carcinomas of the posterior oral cavity and oropharynx (SCCPOCO) associated with HPV p16+. METHODS: Using a retrospective cohort study design, we enrolled a sample of SCCPOCO patients treated in a Central German hospital over a 3-year period. The predictor variables: CPCs, were grouped into demographic, social, anatomic and prognostic. The main outcome variable was p16+. Appropriate statistics were computed, and P≤0.05 was considered statistically significant. RESULTS: Of 199 HNSCC patients, 23 had SCCPOCO and entered the analysis (mean age, 67±12 years; 4 females; 16 in stage I; 4 p16+; 22 underwent primary surgery). We found 8 cervical lymph node metastases (34.8%), 3 distant metastases (13%), 9 recurrences (30.1%) and 3 overall deaths (13%). With the exception of recurrence (P=0.006) and overall death (P=0.02), p16+ was not associated with predictor variables: young age, male gender, smoking, alcohol consumption, tumor location, TNM stages, time to recurrence, metastases, death from disease and survival of smokers (P>0.05). Primary brachytherapy failed to improve survival of p16+-SCCPOCO patients (P=0.04). CONCLUSIONS: The results of this study suggest that p16+- and p16--SCCPOCOs in Central Germany share similar CPCs, except recurrence and overall death. Upfront surgery with/without radio(chemo)therapy is recommended for all operable SCCPOCOs, regardless of HPV-status. Patients with p16+-SCCPOCOs require close follow-up. Future research should investigate the cause of these distinctive CPCs.

Oral lichenoid lesion related to dental amalgam: A case report.

Dental amalgam remains one of standard direct restorative materials for posterior teeth. However, direct contact of oral mucosa with this material can cause oral lichenoid lesion (OLL), albeit rare. It has been proposed that hypersensitivity reaction to mercury is responsible to the pathogenesis of OLL. In addition to clinical features and histopathological examination, allergic patch test and removing the suspected causal material are pivotal to the diagnosis. We reported a case of OLL associated with dental amalgam. The lesion subsided clinically after replacement of amalgam with resin composite material with no need of biopsy or pharmacological treatment. A concise review of clinico-pathological aspects and current recommendations on management of this disease was also presented.

New equations for age estimation using four permanent mandibular teeth in Thai children and adolescents.

The purposes of this study were to generate new age estimation equations using two four-teeth methods and to test the accuracy of the resulting equations in comparison with Demirjian and Goldstein four-teeth methods in a Thai population. A sample of 720 digital panoramic radiographs of Thai individuals (360 males and 360 females), aged between 7 and 15 years was randomly selected and assessed for age estimation. The new equations were developed using quadratic regression analysis. The results showed the Thai population-specific equations had a strong relationship between the dental maturity score and the chronological age in both sexes (r = 0.946-0.956). The new equations revealed no statistically significant differences between the estimated and the chronological ages in either sex. On the other hand, Demirjian and Goldstein four-teeth methods showed statistically significant differences between the estimated and the chronological ages in both sexes. Moreover, we found slight differences in the mean absolute error between Demirjian and Goldstein methods and our new equations (0.01 years for males and 0.03 years for females in method I and 0.04 years for males and 0.02 years for females in method II) and the root mean square error between Demirjian and Goldstein methods and our new equations (0.02 years for males and 0.04 years for females in method I and 0.00 years for males and 0.04 years for females in method II). In summary, although Thai population-specific equations provide a slightly increased accuracy in age estimation in Thai children and adolescents, Demirjian and Goldstein methods are still relevant.

New models for age estimation and assessment of their accuracy using developing mandibular third molar teeth in a Thai population.

Age estimation using developing third molar teeth is considered an important and accurate technique for both clinical and forensic practices. The aims of this study were to establish population-specific reference data, to develop age prediction models using mandibular third molar development, to test the accuracy of the resulting models, and to find the probability of persons being at the age thresholds of legal relevance in a Thai population. A total of 1867 digital panoramic radiographs of Thai individuals aged between 8 and 23 years was selected to assess dental age. The mandibular third molar development was divided into nine stages. The stages were evaluated and each stage was transformed into a development score. Quadratic regression was employed to develop age prediction models. Our results show that males reached mandibular third molar root formation stages earlier than females. The models revealed a high correlation coefficient for both left and right mandibular third molar teeth in both sexes (R = 0.945 and 0.944 in males, R = 0.922 and 0.923 in females, respectively). Furthermore, the accuracy of the resulting models was tested in randomly selected 374 cases and showed low error values between the predicted dental age and the chronological age for both left and right mandibular third molar teeth in both sexes (-0.13 and -0.17 years in males, 0.01 and 0.03 years in females, respectively). In Thai samples, when the mandibular third molar teeth reached stage H, the probability of the person being over 18 years was 100 % in both sexes.

Oral manifestations of HIV infection in relation to clinical and CD4 immunological status in northern and southern Thai patients.

OBJECTIVES: To assess prevalence and variations in the oral manifestations of HIV in HIV-infected subjects in southern Thailand (a new HIV epidemic) and northern Thailand (a mature epidemic), and the association with age, sex, risk behaviours, CD4 count and medication used. SUBJECTS AND METHODS: A total of 102 and 135 HIV-infected individuals were enrolled in northern and southern hospitals, respectively. Oral and haematological examination was performed after sociodemographic interview of the patients. Clinical history was retrieved from patients' medical records. RESULTS: Oral candidiasis (OC, 55%), oral hairy leucoplakia (OHL, 21%) and HIV-associated-periodontal disease (14%) were among the most common oral lesions in southern Thailand. OHL (38%), OC (25%), HIV-associated-periodontal disease (15%) were the three most common lesions in the north. A significant association was found between any oral lesion, OC, particularly the pseudomembranous type (PC), and CD4 < 200 cells mm(-3) at both sites. A negative relationship was found between systemic antifungal treatment and OC including PC and erythematous candidiasis (EC) in the southern data. OHL showed a positive relationship with male sex and a negative relationship with antiretroviral treatment in the northern site. Younger age and being a current smoker were positively associated with oral lesions in the southern group. CONCLUSION: OC, particularly PC, could be useful as a marker for immunosuppression, particularly where CD4 count cannot be determined routinely. Antifungal treatment is of benefit in the subjects who cannot afford highly active antiretroviral therapy (HAART).

A comparative study of epithelial cell proliferation between the odontogenic keratocyst, orthokeratinized odontogenic cyst, dentigerous cyst, and ameloblastoma.

OBJECTIVES: The aim of the present study was to compare the proliferation index of the epithelial cells between odontogenic keratocysts (OKC), orthokeratinized odontogenic cysts (OOC), dentigerous cysts (DC), and ameloblastomas. MATERIALS AND METHODS: The proliferation index, employing a novel cell proliferation marker IPO-38, was studied by the immunohistochemical technique in 10 OKC, seven OOC, eight DC and 10 ameloblastomas. RESULTS: The ameloblastoma had no higher labeling index (LI) of IPO-38 than the OKC (P = 0.910) but had higher LI than the OOC (P = 0.001) and DC (P = 0.000); the OKC had higher LI than the OOC (P = 0.002) and DC (P = 0.000); and the OOC had higher LI than the DC (P = 0.011). IPO-38-positive cells in the OKC and OOC were located principally in the suprabasal cell layers while the ameloblastoma were found in the peripheral portion in particularly, the follicular and plexiform types. CONCLUSION: These findings support previous studies that the proliferation indices are useful in predicting the different biological behavior of the odontogenic lesions and the OKC should be regarded as a benign tumor rather than simply an odontogenic cyst.

Analysis of 587 cases of oral squamous cell carcinoma in northern Thailand with a focus on young people.

The increasing incidence of oral squamous cell carcinoma (SCC) especially among younger people has been observed in many parts of the world. The objective of this study was to delineate the profile of patients with oral SCC with an emphasis on younger people in northern Thailand between 1991-2000. The medical records of 587 (median age 65, male-to-female ratio 1:3:1) patients presenting oral SCC were reviewed, with details of demographic data, staging, histological grading, treatment modality and risk factor profile being collated in detail. Seventy-five patients (12.8%) were 45 years of age or below (median age, 39 years). Most patients regardless of age had stage IV disease (56.2%). The most common histological gradings were well or moderately differentiated SCC (79.4%). The most common site regardless was tongue (42.8%). Most patients (79.4%) received treatments with either radiotherapy alone or a combination of surgery and radiotherapy. 64.4% of patients (87.2%) did not have a familial history of cancer. Collectively this data indicates that oral SCC remains a constant problem to the northern Thai population. In addition, the occurrence of oral SCC in young people is relatively high. Therefore, it is recommended that prevention of oral SCC with early detection, early treatment intervention, and withdrawal from risk habits are important factors for improving the wellbeing of these people.

Oral lesions and dental caries status in perinatally HIV-infected children in Northern Thailand.

UNLABELLED: To describe the prevalence of oral lesions and dental caries status in perinatally HIV-infected children. DESIGN: A cross-sectional study. SETTING: Paediatric HIV outpatient department at the Nakornping Provincial Hospital, Chiang Mai, Thailand. PATIENTS AND METHODS: Forty children with perinatal HIV infection, from early infancy to 12 years of age, were included in the study. These children were examined for oral lesions and dental caries. A number of children receiving antifungal and antiretroviral (ART) therapy were recorded. RESULTS: The mean DMFT and DMFS scores were both 2.1 (SD = 2.3). The dft and dfs scores were 4.1 (SD = 5.0) and 10.9 (SD = 14.8), respectively. A total of 57.5% of the children had one or more oral lesions. Oral candidiasis and hairy leukoplakia were the most common oral lesions. Only 12.5% of children had received ART. A total of 22.5% of the children had a history of receiving antifungal therapy. CONCLUSIONS: Oral lesions and dental caries were relatively high in this study. Consequently, treatment and prevention for oral lesions and dental caries are inevitably required for children with HIV infection in Northern Thailand. Furthermore, ART should be made available for all HIV-infected children to decrease the prevalence of HIV-associated oral lesions.

Oral non-Hodgkin lymphomas: studies of EBV and p53 expression.

OBJECTIVES: The aims of the study were to assess sociodemographic and clinicopathologic characteristics of patients with oral non-Hodgkin lymphomas (NHLs) and the expression of Epstein-Barr virus (EBV) and p53. MATERIALS AND METHODS: The clinical and pathologic features of 11 patients with oral NHLs were studied. The expression of EBV mRNA and p53 protein were studied by means of in situ hybridization and immunohistochemical methods in 11 formalin-fixed, paraffin-embedded specimens from these patients. RESULTS: The patients' age ranged from 13 to 70 years with the mean of 42 years. Human immuno-deficiency virus (HIV) status was documented in five of the 11 patients and three were known to be HIV-positive. The most common locations were gingiva and alveolar mucosa. Pain and tenderness were major symptoms of the patients. The most common histologic subtype was diffuse large-cell, intermediate-grade NHL. Eight of 11 cases (72.7%) showed positive expression of p53 protein. Four of 10 cases (40%) expressed EBV-encoded RNA (EBER) transcripts. All known HIV-positive cases were EBV-positive. CONCLUSIONS: The findings suggest that appropriately expressed p53 protein may play a role in tumorigenesis of oral NHLs. In addition, EBV may be involved with the pathogenesis of oral NHLs particularly in patients with HIV infection.

Endotracheal intubation with thiopental/succinylcholine or sevoflurane-nitrous oxide anesthesia in adults: a comparative study.

We performed a double-blinded, prospective, randomized controlled trial to compare intubating conditions facilitated by succinylcholine or sevoflurane. One hundred twenty patients were randomized to receive either succinylcholine or sevoflurane for tracheal intubation. For the Succinylcholine group, patients were induced with thiopental 5 mg. kg(-1) and tracheally intubated after administration of succinylcholine 1.5 mg. kg(-1) IV. Patients receiving sevoflurane took three vital capacity breaths of 8% sevoflurane and 66% N(2)O in O(2). At the loss of eyelash reflex, ventilation was assisted to establish end-tidal CO(2) between 25-30 mm Hg, and intubation was performed when end-tidal sevoflurane was approximately 6%. Criteria of jaw relaxation, vocal cords position, and intubating response were used to assess intubation condition. If the intubation score was < or = 6 of 12, it was described as acceptable, otherwise it was described as an unacceptable intubation condition. Tracheal intubation was successful in all patients. Intubator and observer blinded as to patient group judged that four patients (6.7%) in the Sevoflurane group and only one patient (1.7%) in the Succinylcholine group had an unacceptable intubation condition. However, there was no significant difference between groups (P > 0.05). Therefore, the three vital capacity breaths inhalation technique with sevoflurane may be an alternative for endotracheal intubation in adults.

A rare, radiographic 'sunray' appearance in fibrous dysplasia.

We report a case of a 19-year-old Thai woman who had fibrous dysplasia (FD) with a rare radiographic 'sunray' appearance. The sunray appearance could have been due to either an unusual pattern of calcification within the lesion or a periosteal reaction.

Amelioration of antigen-induced arthritis in rabbits by induction of apoptosis of inflammatory cells with local application of transdermal photodynamic therapy.

OBJECTIVE: To study the efficacy and mechanism of local transdermal photodynamic therapy (tPDT) in rabbits with antigen-induced arthritis (AIA). METHODS: AIA in rabbits on day 14 postinduction was treated with an intravenous injection of benzoporphyrin-derivative monoacid ring A (BPD; Verteporfin) and subsequent transdermal exposure of the knee joint to light. BPD uptake and PDT-induced apoptosis of the synovium was studied applying fluorescence confocal microscopy and immunohistochemistry. The (histo)pathology of the joints was assessed at day 28. RESULTS: Treatment with tPDT resulted in significant amelioration of synovial inflammation and an almost complete prevention of pannus formation and bone and cartilage destruction. BPD uptake was detectable in activated T cells and macrophages, and there was significant PDT-induced increase in the number of apoptotic cells in the synovium. CONCLUSION: Because photodynamic therapy is both specific and noninvasive, our findings suggest that it could be used for treating arthritic joints in humans.

Expression of 72-kDa gelatinase (matrix metalloproteinase-2) in the developing mouse craniofacial complex.

Tissue remodelling is an important feature during embryogenesis. Although the matrix metalloproteinases are believed to participate in these processes, the relation between matrix metalloproteinases and tissue remodelling during craniofacial morphogenesis remains unclear. The purpose of the study was to look for the presence of enzymes involved in extracellular matrix degradation during craniofacial morphogenesis. Protein expression of the matrix metalloproteinase, 72-kDa gelatinase (matrix metalloproteinase-2, gelatinase A, 72-kDa type IV collagenase) was studied by gelatine zymography and by indirect immunofluorescence with conventional and confocal microscopy. In the anterior region of the developing mouse face, 72-kDa gelatinase was labelled mainly in the tips and peripheral regions of the nasal and facial prominences. Upon contact and fusion of the prominences, the staining was intensely localized to the zone of the fusion and the tips and peripheral regions of the nasal prominences and the maxilla. The labelling of 72-kDa gelatinase was also present in the peripheral regions of the mandible, second branchial arch, and the face around the developing eye. However, during lens vesicle formation, the staining of 72-kDa gelatinase was absent in the invaginated lens ectoderm. After the lens had completely detached from the surface ectoderm, the staining was resumed in the corneal epithelium and mesenchyme. Gelatine zymography was used to confirm the presence of active and latent 72-kDa gelatinase in the developing mouse craniofacial complex. Collectively, these data indicate that 72-kDa gelatinase may play a significant part in localized tissue remodelling during craniofacial morphogenesis and the aberrant expression or function of the enzyme could be involved in causing facial abnormalities.

Cell proliferation and expression of EGF, TGF-alpha, and EGF receptor in the developing primary palate.

Growth factors such as epidermal growth factor (EGF) and transforming growth factor-alpha (TGF-alpha) play an important role in cell proliferation during embryogenesis. The purposes of the study were to characterize the expression patterns of EGF and TGF-alpha and their receptor, EGF receptor (EGF-R), and to analyze regional patterns of cell proliferation during primary palate morphogenesis when facial primordia outgrow and fuse to form the premaxillary and upper lip regions. The expression of all molecules was studied with indirect immunohistochemistry with conventional and/or confocal microscopes in normal days 10 and 11 CD1 mice. 5-Bromodeoxyuridine (BrdU) and proliferating cell nuclear antigen (PCNA) were used as markers of cell proliferation. EGF, TGF-alpha, and EGF-R were found to have similar distribution patterns at all stages examined. In the anterior region of the face, the molecules were intensely localized at the tips and peripheral regions of the medial and lateral nasal prominences. Upon fusion of the facial prominences, all three molecules were present mainly at the fusion area and the tips and peripheral areas of the maxillary and nasal prominences. BrdU and PCNA were found to have distribution patterns similar to those of EGF, TGF-alpha, and EGF-R, with intense staining at the tips and peripheral regions of the facial prominences. These results show that EGF, TGF-alpha, and their receptor were expressed more intensely in regions of the developing primary palate where cell proliferation was most pronounced, and suggest that EGF, TGF-alpha, and EGF-R may play a role in cell proliferation during morphogenesis of the primary palate.

Characterization of verruciform xanthoma by in situ hybridization and immunohistochemistry.

Verruciform xanthoma (VX) is a rare, benign lesion, mainly found in the oral mucosa. Histologically and ultrastructurally, the lesion is characteristic and well defined. However, the etiology of the lesion remains unclear. The purpose of the present study was to elaborate upon the pathogenesis of VX by evaluation of an additional series of oral examples for human papillomaviruses (HPV), using immunohistochemistry and in situ hybridization, and to further characterize the cellular components of VX immunohistochemically. Twelve specimens diagnosed as VX were retrospectively collected. One of the twelve specimens was positive for HPV types 6/11 by in situ hybridization. None of the twelve specimens demonstrated the presence of HPV antigen by immunohistochemistry. By immunohistochemical studies, the predominant cells in the inflammatory infiltrate were T cells. The foam cells were of monocyte/macrophage lineage. S-100-positive (Langerhans) cells were occasionally found in the suprabasal layer of the epithelium. HLA-DR-positive keratinocytes were noted at the intense inflammatory sites. Taken together, these findings suggest that an immune response may play a role, at least in part, in VX pathogenesis.

Distribution of basement membrane components in the mouse primary palate.

Laminin, type IV collagen, and fibronectin are major components of the basement membrane of epithelial tissues. The purpose of this study was to characterize their distributions as the epithelial seam of the primary palate is disrupted and the mesenchymal bridge forms and enlarges. The distributions of these molecules were studied with indirect immunofluorescence in day 11 (9-20 tail somites), noncleft CD1 mice. During epithelial seam formation at 9-11 tail somites (TS), all three molecules were intensely localized in the basement membrane of the seam and adjacent stomodeal and nasal epithelia. During epithelial seam replacement by mesenchymal tissues at 12-18 TS, basement membrane components were first fragmented along the seam, then absent at the site of the mesenchymal bridge. At 19-20 TS, basement membrane components were intact around the margins of the primary palate. These results show that disruption of basement membrane components occurs rapidly and simultaneously with mesenchymal bridge formation in the primary palate.