Management of Medication-Related Osteonecrosis of the Jaw with Photobiomodulation and Minimal Surgical Intervention.

Medication-related osteonecrosis of the jaw (MRONJ) is a relatively common pathology occurring in around 5% of patients taking bisphosphate and other antiresorptive or anti-angiogenic medications. Despite the efforts, as of today there is still no consensus on its management. In this case report, the successful management of stage II MRONJ was performed for an eighty-three-year-old female patient suffering from pain and alteration in her normal oral functions (swallowing and phonation). The treatment consisted of three sessions of photobiomodulation therapy (PBM), followed by minimal surgical intervention and three other sessions of PBM. PBM was applied on the sites of osteonecrosis with the follow parameters: 4 J/cm2; a power of 50 mW; 8 mm applicator diameter; a continuous contact mode. Irradiation was performed on three points, including the vestibular, occlusal and lingual parts of each of the bone exposure areas. Each point was irradiated for 40 s, and, in total, nine points were made per session, and nine sessions were conducted. To assess the pain, a visual analogue scale was used in which zero represented no pain at all and ten represented the greatest pain. At the first session and before any intervention, the patient stated that her pain was 8 out of 10. At the end of the treatment, a significant reduction in VAS was noted (2/10) and, clinically, a healing of the soft tissue in the previously exposed bone was observed. This case report suggests that the combination of PBM with surgical intervention is promising in the management of MRONJ.

Evaluation of the Papillary Gingival Vasculature in Smokers and Nonsmokers with Chronic Periodontitis: A Clinical In Vivo Study.

AIM: Cigarette smoking has been recognized as an important risk factor in periodontal diseases. One of the suggested mechanisms behind this association is that nicotine alters the microcirculation and causes vasoconstriction and reduced blood flow through the periodontal tissues. Scarce information is currently available relative to the microvascular alterations associated with smoking and the distribution of capillaries through the various areas of the gingival tissues. The aims of this study were to assess, in human interproximal gingival biopsies, the number and diameter of gingival capillaries in periodontally affected smokers and nonsmokers using the CD34 immunohistochemical staining method. The pattern of distribution of vessels in the different areas of the gingival tissues was also assessed. MATERIALS AND METHODS: Systemically healthy patients with moderate chronic periodontitis and ranging in age between 30 and 60 years were recruited for the study from the patient population attending the Periodontology Department of the Faculty of Dental Medicine at the Lebanese University of Beirut. The patients were selected to have a group of 10 patients (Group SP) of smokers (>10 cigarettes/day for the last 10 years) and a second group (Group NP) consisting of nonsmoking periodontally affected patients. Three to four weeks following initial preparation, one interproximal gingival biopsy was obtained from each patient. Immunohistochemical staining with CD34 mouse monoclonal antibody was used to identify the endothelial cells of the blood vessels within each sample. Twelve biopsy samples (five in Group NP and seven in Group SP) were chosen for the measurement of the number and diameter of vessels in three regions of the connective tissue of the biopsy under a blinded protocol. RESULTS: In the two groups, the quantitative distribution of small, medium, and large vessels followed a similar trend with the number of small vessels being significantly greater than both medium and large vessels. Small vessels prevailed in the peripheral regions, whereas large vessels were more abundant in the deeper connective tissue areas. The total number of vessels seemed unaffected by chronic cigarette smoking in both groups in the entire biopsy area and in the separate connective tissue regions. Quantitative alteration in the total number of gingival capillaries was not observed in chronic smokers. A redistribution of small and large vessels in the superficial and deeper connective tissue areas of the gingival papilla was noted as a result of smoking in periodontal patients. CONCLUSION: The quantitative distribution of small, medium, and large vessels follows a similar trend with the content in small vessels being significantly more important than both medium and large vessels. Smoking and periodontitis result in a redistribution of small and large vessels in the superficial and deeper connective tissue areas of the gingival papilla compared to nonsmoking periodontal patients. The significance and clinical implications of such rearrangement of vasculature within the gingival tissue need to be further investigated.

Surface Characterization and Cell Adhesion of Different Zirconia Treatments: An in vitro Study.

AIM: The aim of this study was to characterize the surface of zirconia subjected to different treatments and evaluate its effect on cell adhesion and proliferation. MATERIALS AND METHODS: A total of 80 zirconia disks were divided into four groups (n = 20) according to the surface treatments used: group I: as-sintered (AS), no surface treatment applied; group II: abrasion treatment applied using Rocatec (ROC; 3M ESPE) system with silica-coated alumina powder of grit size 110 µm; group III: erbium, chromium:yttrium, scandium, gallium, garnet (Er, Cr:YSGG) laser (LAS; BIOLASE) was used at a frequency of 20 Hz and output power of 3 W; and group IV: specimens were subjected to the selective infiltration etching (SIE) technique. Surface characterization was evaluated for the different groups (roughness, hardness, and morphology), and cell behavior (adhesion and proliferation) was tested (a = 0.05). RESULTS: The ROC group reported a significant increase in surface roughness (2.201 ± 0.352) and Vickers hardness (1758 ± 16.6) compared with the other surface treatments. The SIE surface-treated group reported a significantly higher number of cells (64.5 ± 2.6 and 53.5 ± 2.2 respectively) compared with the other surface-treated groups. CONCLUSION: The SIE is a promising surface treatment for zirconia that significantly enhances cell adhesion and osseointegration. CLINICAL SIGNIFICANCE: The SIE treatment of zirconia implants may help in a faster and better osseointegration.

Lingual Foramina and Canals of the Mandible: Anatomic Variations in a Lebanese Population.

OBJECTIVE: The aim of this study was to evaluate the mandibular lingual foramina (LF) and canals and their anatomic variations using cone-beam computed tomography (CBCT) technology in a Lebanese population. MATERIALS AND METHODS: In this study, we analyzed CBCT images of 90 adult Lebanese patients (41 males and 49 females). We assessed the number and location of the LF. In additional, we measured: (a) The distance from both the alveolar crest and the inferior border of the mandible to the LF and (b) the length of the lingual canals (LCs). The data obtained was analyzed statistically using Shapiro-Wilk normality test, t-test, Chi-square, and Fisher's exact tests. Statistical significance was set at 0.05. RESULTS: In our sample, the LF and canals were present in 93.33% of the CBCT analyzed, and the majority (76.64%) was located above the genial tubercles. The distance from the foramen of the superior and the inferior LCs to the alveolar crest was 16.24 ± 2.82 mm and 25.49 ± 2.43 mm, respectively. The distance from the foramen of the superior canal to the inferior border of the mandible was 14 ± 2.32 mm. The mean length of the superior canal was 5.81 ± 1.6 mm and 4.25 ± 1.2 mm for the inferior one. There were no gender-related differences in the anatomic characteristics of the LF and canals except for the distance measured from the superior canal foramina to the alveolar crest where the measurement was significantly greater in males compared to females. Neither the number of canals nor the positions of the foramina were different between males and females. CONCLUSION: Within the limits of this study, we concluded that in our sample of Lebanese adults, there was substantial variability in the LF and canals anatomy and location.

Mandibular canine dimorphism in establishing sex identity in the lebanese population.

Background and Objective. In forensic investigations, mandibular canines provide excellent materials to identify gender since they are more likely to survive disasters. The objective of this study was to investigate gender dimorphism by comparing the mesiodistal width of mandibular permanent canines and intercanine distance in a group of Lebanese population. Methods. Participants consisted of undergraduate students from the School of Dentistry, Lebanese University, for two academic years who fulfilled the inclusion criteria. Canine widths and intercanine distance were measured by one operator directly on dental casts using a digital caliper. Results. One hundred thirty-three Lebanese dental students (54 males and 69 females) aged 18-25 were included in the study. The intercanine distance was significantly greater in males (P value < 0.0001). The right and the left canine widths were significantly greater in males than in females (P value < 0.0001). However, no significant difference was found between left and right canines for males (P value > 0.05) and females (P value > 0.05). The mean width of canine was greater than 7.188 mm for males. Conclusion. The parameters measured in the present study are of great help in sex identification in forensic investigations in the Lebanese adult population.

Human natural Treg microRNA signature: role of microRNA-31 and microRNA-21 in FOXP3 expression.

Treg are the main mediators of dominant tolerance. Their mechanisms of action and applications are subjects of considerable debate currently. However, a human microRNA (miR) Treg signature has not been described yet. We investigated human natural Treg and identified a signature composed of five miR (21, 31, 125a, 181c and 374). Among those, two were considerably under-expressed (miR-31 and miR-125a). We identified a functional target sequence for miR-31 in the 3' untranslated region (3' UTR) of FOXP3 mRNA. Using lentiviral transduction of fresh cord blood T cells, we demonstrated that miR-31 and miR-21 had an effect on FOXP3 expression levels. We showed that miR-31 negatively regulates FOXP3 expression by binding directly to its potential target site in the 3' UTR of FOXP3 mRNA. We next demonstrated that miR-21 acted as a positive, though indirect, regulator of FOXP3 expression. Transduction of the remaining three miR had no direct effect on FOXP3 expression or on the phenotype and will remain the subject of future investigations. In conclusion, not only have we identified and validated a miR signature for human natural Treg, but also unveiled some of the mechanisms by which this signature was related to the control of FOXP3 expression in these cells.