Aim To evaluate sealing ability and quality of obturation when canal filled with gutta-percha and either mineral trioxide aggregate (MTA), or AH Plus sealer with detection of any possible correlation between microleakage and voids. Materials and methods Human freshly extracted 30 maxillary one-rooted teeth were prepared and assigned to experimental groups (n = 10), designated as group I: gutta-percha/AH Plus, group II: gutta-percha/MTA sealer, group III positive control group (n = 5) teeth unobturated, group IV: negative control group (n = 5) teeth obturated with gutta-percha, AH Plus sealer. After obturation, each tooth was prepared for fluid filtration assessment. Voids detection was performed through cross-sectional analysis at three root levels. Data were analyzed using one-way analysis of variance at a level of confidence of 95%. Results None of the tested obturation systems was able to provide leak proof filling. The sealing ability of MTA FillApex sealer showed higher parameters than AH Plus sealer even if it was not significant. The lowest percent of voids was recorded at the apical third for both tested sealers. The correlation between leakage and voids percentage was nonsignificant. Conclusion Calcium silicate root canal sealer (MTA FillApex) and AH Plus sealer can provide adequate seal with low voids percent. None of the root canal filled teeth were gap-free. Voids percentage cannot be used as an indicator for sealing ability.

Introduction The aim of this study is to compare the debridement efficacy of the EndoVac irrigation system versus needle irrigation with different irrigant solutions using scanning electron microscope. Materials and methods Eighty human freshly extracted single rooted teeth with fully developed, single root canals were collected. The teeth were divided randomly into two equal main groups according to the method of irrigation system used: group A, EndoVac system; and group B, needle irrigation. Each group was further subdivided into four equal subgroups according to the type of irrigant solution used: subgroup 1; sodium hypochlorite (NaOCl), subgroup 2; EDTA, subgroup 3; mixture of tetracycline, acid and detergent (MTAD), subgroup 4; saline. The canals were instrumented to a master apical file size #40/0.02 taper. Roots were split longitudinally in a buccolingual direction and examined under scanning electron microscope. Result At all tested root canal levels, group A recorded lower mean rank of score percentage compared to group B with statistical significant difference between them (P = 0.001 and 0.039 at the middle and the apical root level, respectively), while there was no statistical significant difference between both groups (P = 0.053) at the coronal root level. Conclusion The debridement efficacy of NaOCl only, NaOCl+EDTA, NaOCl+MTAD or even saline increased when using EndoVac system rather than conventional needles especially in the apical third.

Objectives The purpose of this study was to determine the effect of fluoride gel, Remin Pro, and GC tooth mousse plus in changing surface roughness of enamel after bleaching procedures. Materials and methods Dental enamel blocks measuring 2 × 3 × 4 mm were prepared from nonerupted human third molars. The 38% hydrogen peroxide in-office bleaching protocols were performed. The specimens were randomly divided into three groups (n = 10 samples per group) according to the remineralizing agent used: group 1: using fluoride gel, group 2: using Remin Pro, and group 3: using GC tooth mousse plus. Measurements of surface roughness were carried out using a contact stylus profilometer before bleaching, after bleaching, and after remineralization. Results Data were analyzed using analysis of variance and Tukey's test. There was a highly significant difference of enamel surface roughness measurements among initial, after bleaching, and final regarding the three tested groups (P < 0.001). There was no significant difference among the three tested groups in relation to enamel surface roughness before and after bleaching (P = 0.739 and 0.341, respectively). There was a highly significant difference in relation to final measurements (P < 0.001) among the three tested groups. The difference in Ra value of enamel between the group used fluoride gel and that used Remin Pro and GC tooth mousse plus was highly significant and that between groups 2 and 3 was not significant. Conclusion GC tooth mousse plus and Remin Pro are more effective in reducing enamel surface roughness after bleaching than fluoride product.

Objectives The purpose of the current study was to clinically and radiographically assess the regenerative potential of metformin in enhancement of bone healing in third molar extraction sites. Patients and methods The present study included 40 healthy volunteers (27 females and 13 males) aged 21-27 years who had been scheduled for surgical removal of their impacted mandibular third molars. Volunteers were randomly assigned to either groups A or B. Twenty patients of group A (test) underwent surgical removal of impacted mandibular third molar followed by application of metformin gel in the surgical site. Twenty patients of group B (control) underwent surgical removal of impacted mandibular third molar only. Clinical and radiographic evaluation (cone beam computed tomography) was performed immediately after operation and at 6 months postoperatively in terms of the probing pocket depth, the bone defect length at the distal side of second lower molars, and bone density. Data were collected and statistical analysis was performed. Results At 6 months postoperatively group A (test) showed significantly higher (P ≤ 0.001) mean bone density compared with group B (control). On the other hand, there was nonsignificant (P ≥ 0.001) difference in the periodontal pocket depth and defect length between the test and control groups after 6 months. Conclusion There was a significant improvement regarding bone density at the surgical site using metformin after impacted mandibular third molar removal. Thus bone-formative effects of the common oral antihyperglycemic agent MF can provide a new direction in the field of bone healing.

Objective To evaluate the effect of intermaxillary space variation induced by mandibular advancement splints (MAS) constructed with three different interocclusal distances on the efficacy of the treatment of the obstructive sleep apnea. Materials and Methods Ten patients were selected after polysomnography from the Sleep Laboratory in Tanta University. At the beginning of the study all patients were asked to complete the Epworth sleepiness scale and after the treatment period. Each patient received three MAS constructed with intermaxillary distance of 4, 8, and 10 mm and patients were recalled after 4-6 weeks for follow-up study using nasopharyngoscopy and polysomnogram after each appliance. The patients were instructed to withdraw and stop the use of their appliance for at least 1 week before using the next appliance. The recorded data for each patient with the three appliances were collected, tabulated and statistically analyzed using t-paired test and Friedman's test. Results There was statistically significant difference between the baseline records and the records obtained after the use of each MAS appliance (P < 0.05). Conclusion The use of MAS appliance with increased vertical dimension improved the velopharyngeal caliper and improvement in the polysomnographic variables especially Apnea/Hypopnea Index, sleep efficiency and Arousal Index was observed.

Aim/purpose Comparative evaluation of surface roughness of stainless steel (SS), nitinol (NiTi), titanium molybdenum alloy (TMA) and copper nitinol (Cu NiTi) orthodontic arch wires before and after clinical use to find the smoothest wire surface best used in orthodontic sliding mechanics. Materials and methods Surface roughness of 40 arch wires divided into four groups (group 1: 10 SS arch wires, group 2: 10 NiTi arch wires, group 3: 10 TMA arch wires and group 4: 10 Cu NiTi arch wires) were measured at five different points for each wire before and after its clinical use in oral cavity for 4 weeks using atomic force microscope and optical digital microscope. All obtained data was statistically tested. Results SS arch wires had the smoothest surface (average roughness: 17.38 μm for new wires and 104.1 μm for used wires) and Cu NiTi arch wires had the roughest surface (average roughness: 221.12 μm for new wires and 499 μm for used wires) with high significant differences between both groups either new or used arch wires (P < 0.001). High significant difference was found between new and used wires for all groups. NiTi wires had greater surface roughness (average roughness: 211.8 μm for new wires and 313.8 for used wires) than TMA wires (average roughness: 138.5 μm for new wires and 221.2 μm for used wires). Conclusion SS orthodontic arch wires exhibited the least amount of surface roughness and advocated to be used in sliding mechanics to minimize the friction during orthodontic tooth movements.

Objectives The aim of the study was to assess the cellular reaction of baby hamster kidney fibroblast cell line to mineral trioxide aggregate (MTA) and mineral trioxide aggregate mixed with propolis ethanolic extract (MTA-P) at different observation points using the crystal violet proliferation assay. Materials and methods Extracts of the materials were prepared at a surface area-to-volume ratio of 79 mm ² /ml and collected 24, 72 h and 7 days after mixing. Cells were seeded into 96-well plates at 2 × 10 ⁴ cell/well for 24 h and then incubated with 100 μl extracts from each group (n = 6). Cell proliferation was assessed using the crystal violet assay. Cells cultured in culture medium only without the extracts served as control. Statistical analysis was performed using one-way analysis of variance, two-way analysis of variance and independent t-test, P value less than 0.05. Results At 24 h, MTA-P showed higher cell number ratio than MTA (P < 0.05). At 72 h and 7 days, results showed no statistically significant difference among the groups. Conclusion The early biocompatibility of MTA-P seems better than MTA, yet remains constant. MTA biocompatibility, however, seems to improve by time.

Bone destruction due to periodontal disease is one of the factors responsible for loss of teeth. The ultimate goal of periodontal therapy is predictable regeneration of lost periodontal tissue including bone defects. Various bone graft materials have been used for periodontal regeneration, which include autogenous grafts, allografts, xenografts, and synthetically produced ones. Amongst allogenic bone grafts, demineralized freeze-dried bone allograft (DFDBA) is most commonly used. All the bone allografts are osteoconductive, but DFDBA also provide an osteoinductive effect. DFDBA has been successfully used to reconstruct intraosseous periodontal defects and furcation defects. This case report describes the management of an intrabony defect in a maxillary left canine where the osseous defect included loss of buccal wall extending up to the periapical region. This localized periodontitis was successfully treated with periodontal regenerative technique using DFDBAs. DFDBA was used because it contains BMP, which induces new bone formation during the healing process. After 1-year follow-up of treatment, the tooth was functional without any signs and symptoms. Clinical and radiographic changes revealed healthy periodontal support.