Potential effects of advanced platelet rich fibrin as a wound-healing accelerator in the management of alveolar osteitis: A randomized clinical trial.

AIM: The aim of the present study was to determine whether the use of advanced platelet rich fibrin based on the low speed+ centrifugation concept (A-PRF+) might improve the pain management and healing of delayed wound healing among cases of alveolar osteitis following mandibular third molar extraction. MATERIALS AND METHODS: The patients (N = 40) with a complaint of alveolar osteitis following third molar extractions were divided into two groups: Group I (control; saline only); and Group II (use of A-PRF+). Pain was evaluated using the visual analogue scale (VAS). Soft tissue healing was assessed by the modified Index of Landry, Turnbull and Howley and bone density was assessed with the i-Dixel 2.1.8.2 software. Inter-group comparisons were analyzed by means of a student t-test and the Mann Whitney U test to identify group samples. Analysis of variance and the Friedman test were applied for repeated measurements. The Wilcoxon test and Bonferroni's test for multiple comparisons were conducted at the time-factor level. Yates Correction was used to compare qualitative data. RESULTS: In regard to pain, A-PRF+ application demonstrated rapidly and continually reduced pain intensity at each respective time in comparison to the control. Statistically, the healing rates of epithelium and hard tissue were significantly faster in the A-PRF+ application group (p: 0.000, P < 0.05). CONCLUSIONS: The results show that A-PRF+ might represent an improved and accelerating therapeutic development for hard and soft tissue healing in management of alveolar osteitis that is also effective in reducing pain.

Comparison of efficiency of hyaluronic acid and/or bone grafts in healing of bone defects.

BACKGROUND: Reconstruction of bone defects in oral and maxillofacial surgery has widespread uses. In recent years, the capacity of various biomaterials alone or in combination with bone graft materials to increase bone healing has been an intensive research topic. The aim of this study is to evaluate the efficacy of hyaluronic acid and/or bone graft material on bone healing in defects created in the rat mandible. Methods: In our study, rats were divided into 4 groups. Group 1 is designated to be treated with no materials, Group 2 with graft material, Group 3 with only hyaluronic acid, and Group with hyaluronic acid and graft material. A critical-size defect of 5 mm in diameter was created bilaterally in the rat mandibles and the rats were divided into the indicated groups accordingly. At the end of the postoperative 6th week, the experiment was terminated. The right halves of the mandibles were evaluated immunohistochemically and histopathologically in terms of bone healing, and the left in terms of mineralization level via microcomputed tomography. RESULTS: Histopathological evaluation showed that healing in the empty group was significantly lower than the other groups that were treated with materials (P < 0.05); but the difference between the material-treated groups was not significant. Immunohistochemical evaluation revealed that the staining was moderately positive/strongly positive in all groups, but the difference between the groups was not significant. The highest mineralization values observed in the defected areas that belonged to 2 groups using hyaluronic acid, and the difference between them was found to be statistically significant (P < 0.05). The lowest mineralization values observed in the defected areas was most frequent in the group where only the hyaluronic acid was used, and there was a statistically significant difference between the other groups (P < 0.05). CONCLUSION: In conclusion, the use of hyaluronic acid alone or in combination with bone grafting has been shown to contribute positively to the improvement of bone defects in the jaw area.

Oral mucosa and lung cancer: Are genetic changes in the oral epithelium associated with lung cancer?

AIM: To compare genetic aberrations in the oral epithelium of lung cancer patients with those without cancer. SUBJECTS AND METHODS: Buccal smears were performed to collect oral epithelium from each of the participants (smoker cancer patients n = 50, smoker control subjects n = 40, and nonsmoker control subjects n = 25). Cytogenetic changes in the samples were detected by micronuclei assay, whereas p53 and murine double minute 2 (MDM2) polymorphisms were genotyped using polymerase chain reaction-restriction fragment length polymorphism. RESULTS: p53 codon 72 polymorphism was seen in 44% of cancer patients versus 12.5% in smokers and 12% in nonsmokers of the control group. Similarly, MDM2 single nucleotide polymorphism 309 polymorphism was seen in 34% of patients with lung cancer as opposed to 12.5% of smokers (P = 0.038) and 8% of nonsmokers (P = 0.019) of the control group. CONCLUSION: A higher proportion of individuals with lung cancer demonstrate genetic damage to oral mucosa compared to those without cancer.

Oral health in patients on inhaled corticosteroid treatment.

OBJECTIVE: The aim of this study was to investigate the effects of long-term inhaled corticosteroids on bone mineral density (BMD) of the mandible in relation with the tooth loss. DESIGN: Cross sectional analytic study. SUBJECTS AND METHODS: Patients (n = 30) with chronic obstructive pulmonary disease under inhaled corticosteroid therapy for at least 1 year were compared with sex- and age-matched healthy controls (n = 30). BMD of the mandible was measured by dual-energy X-ray absorptiometry. The clinical examination included recording the number of teeth present together with periodontal condition. Levels of serum osteocalcin, alkaline phosphatase, calcium, phosphorus and cortisol were also assessed. RESULTS: BMD of the mandible in patients on corticosteroid treatment was significantly lower than that in the control group (P = 0.001). Patients under treatment had more missing teeth than the control group but the difference did not reach statistical significance. The two groups exhibited similar clinical parameters of periodontal condition. Significantly lower levels of osteocalcin (P < 0.0001), calcium (P = 0.004) and cortisol (P = 0.03) were observed in the patients on corticosteroid treatment. CONCLUSION: Long-term use of inhaled corticosteroids may impair bone metabolism and lead to a marked decrease in the mandibular BMD.

In vivo killing of Porphyromonas gingivalis by toluidine blue-mediated photosensitization in an animal model.

Porphyromonas gingivalis is one of the major causative organisms of periodontitis and has been shown to be susceptible to toluidine blue-mediated photosensitization in vitro. The aims of the present study were to determine whether this technique could be used to kill the organism in the oral cavities of rats and whether this would result in a reduction in the alveolar bone loss characteristic of periodontitis. The maxillary molars of rats were inoculated with P. gingivalis and exposed to up to 48 J of 630-nm laser light in the presence of toluidine blue. The number of surviving bacteria was then determined, and the periodontal structures were examined for evidence of any damage. When toluidine blue was used together with laser light there was a significant reduction in the number of viable P. gingivalis organisms. No viable bacteria could be detected when 1 mg of toluidine blue per ml was used in conjunction with all light doses used. On histological examination, no adverse effect of photosensitization on the adjacent tissues was observed. In a further group of animals, after time was allowed for the disease to develop in controls, the rats were killed and the level of maxillary molar alveolar bone was assessed. The bone loss in the animals treated with light and toluidine blue was found to be significantly less than that in the control groups. The results of this study show that toluidine blue-mediated lethal photosensitization of P. gingivalis is possible in vivo and that this results in decreased bone loss. These findings suggest that photodynamic therapy may be useful as an alternative approach for the antimicrobial treatment of periodontitis.

Fluorescence biodistribution and photosensitising activity of toluidine blue o on rat buccal mucosa.

The antimicrobial activity of toluidine blue O (TBO) in the presence of red light has been demonstrated for a wide range of microorganisms. The response of tissues to TBO-induced photosensitisation is an important factor in assessing the clinical usefulness of this technique for the treatment of infectious diseases. The aims of this study were to determine the effect of TBO-mediated photosensitisation on rat buccal mucosa and the biodistribution of the photosensitiser in this tissue. An aqueous solution of TBO was applied to one side of the buccal mucosa of the animals. A 6 mm diameter area was then exposed to light (633 nm) from a copper vapour pumped-dye laser. The opposite, untreated, side of the buccal mucosa served as a control. TBO concentrations of 25, 50 and 200 microg/ml, laser light doses of 110, 170 and 340 J/cm(2) were assessed. Control groups of animals were subjected to 340 J/cm(2) laser light alone or to 200 microg/ml TBO alone. Serial sacrifices were performed after 72 h to obtain mucosal tissue samples for histological examination. For the determination of TBO biodistribution, additional groups received the same TBO doses and were sacrificed after 1 min or 10 min. Specimens were removed and frozen immediately for digital fluorescence imaging. No necrotic or inflammatory changes were found in the buccal mucosa of the animals with any of the treatments (using up to 200 microg/ml TBO and 340 J/cm(2) laser light). A high TBO fluorescence in the epithelium, particularly in the keratinised layer, with almost no fluorescence in the underlying connective tissue was demonstrated by the digital imaging. The results of this study suggest that TBO-mediated PDT (within the concentrations and light doses tested) could be a safe antimicrobial approach for the oral infections without damaging the adjacent normal tissue.

Factors influencing the susceptibility of Gram-negative bacteria to toluidine blue O-mediated lethal photosensitization.

AIMS: Bacteria can be killed by red light in the presence of a photosensitizer. The purpose of this study was to evaluate the effect of physiological and environmental factors on the susceptibility of some bacteria associated with oral infections in immunocompromised patients to killing by the photosensitizer toluidine blue O (TBO). METHODS AND RESULTS: Suspensions of Pseudomonas aeruginosa, Escherichia coli and Klebsiella pneumoniae in human saliva, horse serum or saline were exposed to light from a helium/ neon laser in the presence of TBO. Additional suspensions at various growth phases and pHs were treated in an identical manner. Survivors were enumerated by viable counting. All three species were susceptible to lethal photosensitization under all of the conditions tested. The presence of serum and, to a lesser extent, saliva decreased the level of kill attained. The bactericidal effect was reduced at acid pHs but was unaffected by the growth phase of the organism. CONCLUSIONS: The composition and pH of the fluid in which bacteria are suspended influenced the effectiveness of TBO-mediated lethal photosensitization, whereas killing was unaffected by the growth phase of the organism. SIGNIFICANCE AND IMPACT OF THE STUDY: Environmental factors operating in the mouths of patients with mucositis could reduce the effectiveness of TBO-mediated lethal photosensitization of bacteria associated with this condition.

The effect of photodynamic action on two virulence factors of gram-negative bacteria.

Photodynamic therapy could provide an alternative to antibiotics for the treatment of local infections since a wide range of microorganisms have been shown to be susceptible to killing by photodynamic action (PDA) in vitro. The purpose of this study was to determine whether PDA was also able to affect the potency of two key bacterial virulence factors--lipopolysaccharide (LPS) and proteases. Suspensions of LPS from Escherichia coli and culture supernatants containing proteases of Pseudomonas aeruginosa were exposed to red light in the presence of toluidine blue O (TBO). The activity of each virulence factor was determined before and after irradiation. The limulus amoebocyte lysate (LAL) assay and the induction of proinflammatory cytokine (interleukin-8 and -6) release from human peripheral blood mononuclear cells (PBMC) were used for assessing the biological activity of LPS. Protease activity was quantified by azocasein hydrolysis. The biological activities of the LPS (both the LAL activity and its ability to induce cytokine release from PBMC) and the proteases were reduced significantly by irradiation with red light in the presence of TBO in a dose-dependent manner with respect to both the light energy dose and the TBO concentration. The ability of TBO-mediated PDA to reduce the activities of key virulence factors may be an additional benefit of using light-activated antimicrobial agents in the treatment of infectious diseases.