Se Udeabor

Squamous cell carcinoma of the oral cavity and the oropharynx in patients less than 40 years of age: a 20-year analysis

BackgroundSquamous cell carcinoma mainly afflicts patients older than 40 years of age however, few cases are seen in younger patients. The aim of this study therefore was to determine the incidence of squamous cell carcinoma of the oral cavity and oropharynx in patients less than 40 years of age with a view to assessing the prognosis over a period of time.MethodsThis was a 20 years retrospective review of patients who were histologically diagnosed with squamous cell carcinoma of the oral cavity and the oropharynx at the Department of Cranio-Maxillo-Facial Surgery of the Hannover Medical School, Germany and had not received treatment anywhere else. Records of these patients were analysed for age and sex distribution, tumour staging and differentiation, location, treatment given, recurrences and metastasis, time between diagnosis and death or last contact with patient, and possible cause of death. Comparisons were also made with patients older than 40 years of age.Results and discussionA total of 977 patients treated for squamous cell carcinoma of the oral cavity and the oropharynx in the 20-year period of this study were included. Thirty eight (3.9 %) of the overall patient population were under 40 years of age. Among these, 30 (78.9%) were males and 8 (21.1%) were females. The incidence was highest in the 30–39 year age group accounting for 31 (81.6%) of the 38 patients. The moderately differentiated carcinoma was commonest (24; 63.2%). The floor of the mouth had the highest number of tumours (15; 39.5%), but none was seen in the oropharynx. Surgery alone was the main stay of treatment given to 26 (68.4%) patients. At the end of the study period, 13 (34.2%) patients had died of the tumour and the 5-year survival rate was 66.2%. In the older patient group (>40 years), 42.7% died from the tumour and the 5-year survival rate was 57.6%.ConclusionThe results from the present study showed that young adults may have a better prognosis especially in terms of long term overall survival from oral and oropharyngeal carcinoma.

Implantation of silicon dioxide-based nanocrystalline hydroxyapatite and pure phase beta-tricalciumphosphate bone substitute granules in caprine muscle tissue does not induce new bone formation

BackgroundOsteoinductive bone substitutes are defined by their ability to induce new bone formation even at heterotopic implantation sites. The present study was designed to analyze the potential osteoinductivity of two different bone substitute materials in caprine muscle tissue.Materials and methodsOne gram each of either a porous beta-tricalcium phosphate (β-TCP) or an hydroxyapatite/silicon dioxide (HA/SiO2)-based nanocrystalline bone substitute material was implanted in several muscle pouches of goats. The biomaterials were explanted at 29, 91 and 181 days after implantation. Conventional histology and special histochemical stains were performed to detect osteoblast precursor cells as well as mineralized and unmineralized bone matrix.ResultsBoth materials underwent cellular degradation in which tartrate-resistant acid phosphatase (TRAP)-positive osteoclast-like cells and TRAP-negative multinucleated giant cells were involved. The ß-TCP was completely resorbed within the observation period, whereas some granules of the HA-groups were still detectable after 180 days. Neither osteoblasts, osteoblast precursor cells nor extracellular bone matrix were found within the implantation bed of any of the analyzed biomaterials at any of the observed time points.ConclusionsThis study showed that ß-TCP underwent a faster degradation than the HA-based material. The lack of osteoinductivity for both materials might be due to their granular shape, as osteoinductivity in goat muscle has been mainly attributed to cylindrical or disc-shaped bone substitute materials. This hypothesis however requires further investigation to systematically analyze various materials with comparable characteristics in the same experimental setting.

Induction of multinucleated giant cells in response to small sized bovine bone substitute (Bio-Oss TM ) results in an enhanced early implantation bed vascularization

Purpose: The host tissue reaction to the xenogeneic bone substitute Bio-Oss™ (Geistlich Biomaterials, Wolhousen, Switzerland) was investigated focusing on the participating inflammatory cells and implantation bed vascularization. Materials and Methods: Bio-Oss™ was implanted subcutaneously into CD1 mice for up to 60 days and analyzed by means of specialized histological and histomorphometrical techniques after explantation. Results: Bio-Oss™ induced within the first 15 days an early high vascularization combined with a marked presence of multinucleated giant cells. The latter cells were associated mainly with the smaller sized granules within the implantation bed. Toward the end of the study the number of multinucleated giant cells decreased while the tissue reaction to the larger granules was mainly mononuclear. Conclusion: The results of the present study showed that smaller xenogeneic bone substitute granules induce multinucleated giant cells, whereas the larger-sized ones became integrated within the implantation bed by means of a mononuclear cell-triggered granulation tissue. Obviously, the presence of multinucleated giant cells within biomaterial implantation beds is not only related to the type of synthetic bone substitute material, but also to the granule size of the natural-based xenogeneic bone substitute material.

High-Temperature Sintering of Xenogeneic Bone Substitutes Leads to Increased Multinucleated Giant Cell Formation: In Vivo and Preliminary Clinical Results

The present preclinical and clinical study assessed the inflammatory response to a high-temperature-treated xenogeneic material (Bego-Oss) and the effects of this material on the occurrence of multinucleated giant cells, implantation bed vascularization, and regenerative potential. After evaluation of the material characteristics via scanning electron microscopy, subcutaneous implantation in CD-1 mice was used to assess the inflammatory response to the material for up to 60 days. The clinical aspects of this study involved the use of human bone specimens 6 months after sinus augmentation. Established histologic and histomorphometric analysis methods were applied. After implantation, the material was well integrated into both species without any adverse reactions. Material-induced multinucleated giant cells were observed in both species and were associated with enhanced vascularization. These results revealed the high heat treatment led to an increase in the inflammatory tissue response to the biomaterial, and a combined increase in multinucleated giant cell formation. Further clarification of the differentiation of the multinucleated giant cells toward so-called osteoclast-like cells or foreign-body giant cells is needed to relate these cells to the physicochemical composition of the material.

Pattern of midface trauma with associated concomitant injuries in a Nigerian referral centre

Aim: The aim of this study was to determine the pattern of midface trauma with associated concomitant injuries seen in our environment. Methodology: This was a prospective analysis of trauma patients with midfacial injuries presenting at a referral center in South West Nigeria. In addition to socio-demographic data, the following information was also obtained: Mechanism of injuries, type of midfacial injuries, concomitant/associated injuries and treatment. Results: A total of 101 patients with midfacial injuries were involved. They were made up of 85 males and 16 females. The 20-29 year age group was mostly affected (44.6%) and the most common cause of midface injuries was road traffic accident (91.1%). The zygoma was fractured more than any other midfacial bone (46.0%). A total of 144 associated injuries were recorded among these patients, head and ocular injuries accounted for 49 (34%) and 35 (24.3%) respectively. The patients were mostly treated conservatively or by closed reduction. Conclusion: The rate of head and ocular injuries among patients with midfacial injury was high. Knowledge of these associated injuries provides useful strategies for patient care and prevention of further complications. A multidisciplinary approach is important for optimum management of these patients.

Maxillofacial Fractures: Etiology, Pattern of Presentation, and Treatment in University of Port Harcourt Teaching Hospital, Port Harcourt, Nigeria

Objective. To retrospectively analyze the pattern of presentation and modalities of management of maxillofacial fractures in our center. Methods. The medical records of all the patients who sustained maxillofacial fractures presenting to a major referral hospital in Niger Delta region of Nigeria were retrieved and reviewed. The data collected was analyzed using SPSS statistical package. Results. Eighty-six patients presented with 135 maxillofacial fractures during the period under review. A male to female ration of 3 : 1 was recorded and patients in their third decade of life were mostly affected (46.5%). Road traffic accident (RTA) was the commonest etiology accounting for 46.5% whereas assault was second (19.8%). The mandible was the most frequently fractured bone (59.3%) followed by the zygoma (18.5%). The main stay of treatment was closed reduction with IMF (40.4%). Conclusion. Treatment modalities for maxillofacial fractures in our center have not witnessed any significant changes. Effort should be made to ensure the availability of miniplates to ensure adequate treatment for all categories of our patients.

Osteocalcin, Azan and Toluidine blue staining in fibrous dysplasia and ossifying fibroma of the jaws

Abstract Background Fibrous dysplasia (FD) and ossifying fibroma (OF) are fibro-osseous lesions (FOLs) having several overlaps that may make final diagnosis difficult by hematoxylin and eosin (H/E) alone. Aim This study seeks to detect any association between Azan and Toluidine blue staining as compared with osteocalcin in FD and OF diagnosis. Methods Forty formalin fixed paraffin embedded (FFPE) blocks of FD and OF were prepared for Azan, Toluidine blue and osteocalcin staining. Brown staining of calcified structures was considered as positive for osteocalcin. Scoring for Azan and Toluidine blue was evaluated based on intensity and localization. Level of agreement of original and revised diagnosis was determined. Results Six (40%) of 15 FD were corroborated by osteocalcin. Eight cases initially diagnosed as OF were revised to FD. There were 25 OF according to H/E, and 17 (68%) were validated by osteocalcin. Measure of agreement between histology and immunohistochemistry was 0.081; p = .608. Eleven (42.3%) OF expressed strong toluidine blue staining of the intervening fibrous connective tissue stroma while only 2 (14.2%) FD showed similar staining, this difference was statistically significant [p = .001]. Conclusions Histomorphometric analysis with Toluidine blue may reduce diagnostic errors of OF and FD.

The utility of azan trichrome staining in Ameloblastoma

Background: It is occasionally difficult to distinguish the stellate reticulum-like region of ameloblastoma from the fibrous connective tissue stroma. This difficulty is further pronounced in the plexiform variant of ameloblastoma that has very sparse fibrous connective tissue. Aim: To test the utility of Azan trichrome stain in marking tumour regions and the peri-tumour environment of ameloblastoma. Materials and Methods: Sections were prepared for 18 formalin fixed paraffin-embedded blocks of ameloblastoma cases and stained with Azan trichrome stain according to the manufacturer′s specification. Results and Conclusions: The tumour areas were stained mostly brown, with the ameloblasts mainly marked as deep brown while the stellate reticulum-like region was light brown. The structures in the peri-tumour region were marked with different shades of blue. Azan trichrome staining was able to distinguish between the fibrous connective tissue and the stellate reticulum-like areas in 100% of the cases.

PTCH-1 and MDM2 expression in ameloblastoma from a West African sub-population: implication for chemotherapeutics

Introduction Ameloblastoma is a slow growing, painless odontogenic swelling which can attain sizes that result in severe deformities of the craniofacial complex. It is the most commonly encountered odontogenic tumor in Nigeria. Surgical intervention is currently the method of treatment; however identification of altered molecular pathways may inform chemotherapeutic potential. The Protein Patched homolog 1 (PTCH-1) is overexpressed in ameloblastoma. Also, mutation in the MDM2 gene can reduce the tumor suppressor function of p53 and promote ameloblastoma growth. No study however has characterized the molecular profile of African cases of ameloblastoma with a view to developing chemotherapeutic alternatives. The objective was to characterize the PTCH-1 genetic profile of Ameloblastoma in Nigerian patients as a first step in investigating its potential for chemotherapeutic intervention. Methods Twenty-eight FFPE blocks of ameloblastoma cases from Nigerian patients were prepared for antibody processing to PTCH-1 (Polyclonal Anti-PTCH antibody ab39266) and MDM2 (Monoclonal Anti-MDM2 antibody (2A10) ab16895). Cytoplasmic brown staining was considered as positive for PTCH while nuclear staining was positive for MDM2. Results Moderate and strong expressions for PTCH in ameloblast and stellate reticulum were 78.6% and 60.7% respectively. Only 3 (10.7%) cases expressed MDM2. Conclusion The importance of our study is that it supports, in theory, anti-PTCH/SHH chemotherapeutics for Nigerian ameloblastoma cases and also infers the possible additional use of anti-p53 agents.

Relative expression of α-smooth muscle actin and matrix metalloproteinases-2 in ameloblastoma of a black African sub-population.

BACKGROUND Ameloblastoma although a benign odontogenic tumor, is locally invasive. The abundant presence of myofibroblasts (marked by α-smooth muscle actin [α-SMA]) in the stroma and expression of matrix metalloproteinase-2 (MMP-2) in the neoplastic or stromal cells have been linked with the tumors ability for both local and distant spread. We aim to estimate the relative expression of α-SMA and MMP-2 in ameloblastoma from a black African subgroup to gauge their relative potential for enhancing local invasiveness and hence, their prospects as possible chemotherapeutic targets. MATERIALS AND METHODS Twenty-five formalin-fixed paraffin-embedded blocks of ameloblastoma cases from Nigeria were prepared for antibody processing to α-SMA (Dako Monoclonal Mouse Anti-Human α-SMA antibody clone 1A4) and MMP-2 (Abcam Mouse Monoclonal Anti-MMP-2 antibody [CA-4001/CA719E3C] ab3158). The score for percentage positivity of the tumor cells and the score for staining intensities were then multiplied in order to generate an immunoreactive score. RESULTS α-smooth muscle actin was only expressed in the fibrous connective tissues adjacent to the tumor islands while MMP-2 was expressed in the ameloblasts, stellate reticulum, and the connective tissues in varying proportions. All the variants analyzed expressed α-SMA mildly or moderately, except for the follicular variant that either did not express α-SMA or expressed it mildly. The highest number of strong immunoreactivity to MMP-2 in the ameloblast region was found in the plexiform variant. CONCLUSION Chemotherapeutic targeting of both molecules may, therefore, be a vital step in the control of local ameloblastoma invasiveness.