Current Knowledge on the Healing of the Extraction Socket: A Narrative Review.

The concept of extraction socket healing has been severally researched and reported over the years, since tooth extraction remains one of the most common procedures performed in the dental clinic. Understanding this healing process is of utmost importance because the outcome has a direct bearing on future prosthetic rehabilitation and, by extension, on patients' esthetics and masticatory function, among others. This mini review, therefore, summarized the current knowledge on the different stages of socket healing, including the biologic and clinical events that occur following tooth extraction up until the complete closure of the socket. Additionally, the modeling of the alveolar bone/process post extraction, and the resultant dimensional changes that, altogether, shape the bone, were reviewed and documented. The effects of various socket preservation interventions to mitigate these dimensional changes, and therefore preserve the alveolar process in a condition suitable for future prosthetic rehabilitation, were highlighted. Finally, a review of some of the factors that influence the entire process was also carried out.

Modified micromarsupialization technique as an alternative primary treatment for ranulas: A case series in a resource-challenged economy.

OBJECTIVES: Ranula is one of the commonest salivary gland cysts that mostly occur due to mucus extravasation from the sublingual salivary gland. Treatment of this lesion is still somewhat shrouded in controversy and varies from conservative treatment to surgical excision of the causative gland. MATERIALS AND METHODS: This was a case series in quasi-experimental design that evaluated the outcome and complications of the modified micromarsupialization technique as a newly introduced treatment at our center for simple sublingual ranula over a 2-year period. RESULTS: Twenty patients were treated by the modified micromarsupialization technique and followed up for 1 year. There was complete resolution following this technique in 17 patients (85%) with no evidence of recurrence or complications, whereas 2 patients (10%) showed partial resolution and the remaining 1 patient (5%) showed a failure and recurrence. The age of the patient, the size of the ranula, and the retention of sutures throughout the study period did not significantly affect the treatment outcome. CONCLUSIONS: The modified micromarsupialization technique was a simple and effective treatment that should be used as a primary treatment option for simple ranulas and we recommend it to be the first-choice treatment before surgical excision of the sublingual gland, especially in a resource-challenged economy like ours.

Serum levels of 25-hydroxy-vitamin D in patients with oral squamous cell carcinoma: Making a case for chemoprevention.

OBJECTIVES: Serum level of vitamin D has been used as a predictor for cancer development. We intend to measure the baseline vitamin D level in patients with oral squamous cell carcinoma (OSCC) and to compare same with non-cancer controls to determine any association. MATERIALS AND METHODS: Patients with OSCC presenting to our clinics were included in this study. Their baseline serum vitamin D levels were measured prior to cancer treatment after obtaining their consents. These patients were then matched with at least 2 cancer-free subjects to serve as controls and whose serum vitamin D levels were also measured. The serum vitamin D levels obtained for the two groups were then categorized into normal (>35 ng/ml), mild deficiency (25-35 ng/ml), moderate deficiency (12.5-25 ng/ml), and severe deficiency (<12.5 ng/ml). The data were analyzed statistically and the two groups compared. RESULTS: A total of 51 patients with OSCC (Male 22 [43%] and female 29 [57%]) and 113 cancer-free controls (Male 36 [31.86%] and female 77 [68.14%]) were included in the study. The commonest site for OSCC was the tongue, accounting for 45% of the cancer cases. Mean age for cancer patients was 59.33 years ±12.54 and 49.24 years ±15.79 for the control. Among the OSCC patients, 74.51% had moderate to severe vitamin D deficiencies, whereas only 20.35% had a moderate deficiency in the control group with no severe deficiency. CONCLUSION: Logistic regression analysis shows a positive association between vitamin D deficiency and OSCC risk especially in levels below 25 ng/ml. This further corroborates the assertion that vitamin D deficiency may be a useful indicator of OSCC. It may, therefore, be necessary to routinely prescribe vitamin D supplements to subjects with moderate to severe deficiencies in order to decrease the chances of OSCC development.

Evaluation of Tumour Associated Macrophages and Angiogenesis in Ameloblastoma.

INTRODUCTION: Ameloblastoma is a locally invasive odontogenic neoplasm that has a high recurrence rate. The invasion of adjacent tissue is supported by angiogenesis stimulated by Tumour-Associated Macrophages (TAMs). TAMs are macrophages modified in the milieu of the tumour microenvironment and have very weak or no ability to present antigens. Thus, there is collaboration between the tumour and the tumour microenvironment to maintain tumour enlargement. TAMs exist as the classically activated M1 macrophages that possess antitumour activity and the otherwise activated M2 macrophages that support tumour invasion and metastasis. AIM: To investigate the relative expression and topography of TAMs and CD34 in ameloblastoma in order to assess their affiliation and effect on tumour growth. MATERIALS AND METHODS: Forty-six Formalin Fixed Paraffin Embedded (FFPE) blocks of ameloblastoma were processed for Abcam Mouse monoclonal Anti-CCR7 antibody, Abcam Rabbit polyclonal Anti-CD206 antibody and Dako Mouse monoclonal Anti-CD34 antibody QBEnd-10. Cytoplasmic/membrane brown staining was taken as positive for all antibodies. The relative percentage of TAMs was classified as: <5%, 5-25%, 25-50% and >50%. TAMs related Microvessel Density (MVD) was evaluated as the mean of the three-recorded values. Cases with no CD34+ vessels adjacent to the TAMs region had MVD score of 0. Simple descriptive statistics was applied. RESULTS: Macrophages adjacent to peri-tumour islands were marked by CD206 and CCR7 and we noted negligible intra-tumour presence of positive macrophages. The percentage of positive CCR7 immune cells was greater than that for CD206 in 38 (82.6%) cases, approximately equal to CD206 in 6 (13%) cases, and the CD206 expression was more than CCR7 in only 2 (4.3%) cases. In 34 (73.9%) cases, the area of MVD did not overlap with the region of TAMs but in 4 (8.7%) cases (where MVD overlapped TAM1), the average MVD score was 20. CONCLUSION: The relative percentage of TAM1 exceeds TAM2 in peri-tumoural areas of ameloblastoma, conferring anti-angiogenic and hence anti-tumour activity on the tumour.

Tumor-associated macrophages, angiogenesis, and tumor cell migration in oral squamous cell carcinoma.

OBJECTIVE: To investigate the relationship between tumor-associated macrophages (TAMs), neovascularization, and tumor cell migration in oral squamous cell carcinoma (OSCC) of an African subpopulation. MATERIALS AND METHODS: Twenty OSCC paraffin blocks underwent immunohistochemistry to TAM1 (CCR7), TAM2 (CD206), Twist, E-cadherin, N-cadherin, and CD34. The relative percentage of CCR7 + and CD206 + cells to overall immune cell population was calculated for three high power fields and an average was taken. TAM-related microvessel density (MVD) was determined as the mean of the three recorded values. Cases that had no CD34 + vessels adjacent to the TAMs region were regarded as having an MVD score of 0. RESULTS: Ten cases (50%) expressed greater CCR7 activity than CD206, seven cases (35%) expressed approximately equal activity of CCR7 and CD206, while three cases (15%) expressed greater activity of CD206 than CCR7. Twist expression was strong in some cases with strong N-cadherin and weak E-cadherin, but the expression of Twist was not consistently high in all cases that expressed strong N-cadherin and weak E-cadherin. CONCLUSIONS: TAMs distribution suggested antitumor activity and the potential for tumor metastasis was only partly due to Twist-mediated epithelial-mesenchymal transition.

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.

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 tumor's 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.

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.

BACKGROUND: Osteoinductive 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 METHODS: One gram each of either a porous beta-tricalcium phosphate (ß-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. RESULTS: Both 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. CONCLUSIONS: This 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.

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

BACKGROUND: Squamous 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. METHODS: This 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 DISCUSSION: A 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%. CONCLUSION: The 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.