ABSTRACT
OBJECTIVE: The purpose of this study was to examine the effect of commercially available fluoride-containing oral rinses on the corrosion behavior of titanium alloys, which are the main components of orthodontic miniscrews. METHODS: Four commercially available oral rinses (solution A, pH 4.46/260 ppm fluoride; solution B, pH 4.41/178 ppm fluoride; solution C, pH 6.30/117 ppm fluoride; and solution D, pH 4.17/3.92 ppm fluoride) were tested on titanium alloy (Ti-6Al-4V) circular plates, and saline was used as the control. The open-circuit potential and potentiodynamic polarization of these materials were measured. Thereafter, all samples were evaluated under a field-emission scanning electron microscope. RESULTS: Among the tested oral rinses, except solution D, the more the fluoride content was, the greater was the corrosion potential downtrend; the corrosion resistance of the titanium alloy sample was also lowered significantly (p < 0.05). Field-emission scanning electron microscopic analysis of the surface morphology of the titanium alloy samples revealed that all samples had some defects, crevices, or pitting after exposure to the oral rinses than before treatment. In particular, the samples in solution A showed the most changes. CONCLUSIONS: Commercially available oral rinses having a high fluoride concentration and a low pH may reduce the corrosion resistance of titanium alloys used in dental appliances such as orthodontic titanium miniscrews and brackets.
Subject(s)
Alloys , Corrosion , Fluorides , Hydrogen-Ion Concentration , TitaniumABSTRACT
CONTEXT: Early detection of oral premalignancy and malignancy using simple screening aids play a promising role in curbing the disease. AIM: The primary aim of this study is to evaluate and the secondary aim of this study is to compare the cytomorphometry and cellular atypia in keratinocytes obtained from oral rinse and conventional exfoliative cytology in normal oral mucosa and clinically diagnosed oral leukoplakia. MATERIALS AND METHODS: The study comprised of 55 clinically diagnosed cases of leukoplakia and 55 age and sex matched normal controls. Smears were prepared using oral rinse technique followed by the conventional exfoliative cytology. Papanicoloau stained smears were evaluated for atypia and subjected to image analysis. Based on the presence of atypia they were further divided into three groups (Group 1‑cases with atypia, Group 2‑without atypia and Group 3‑normal controls) and analyzed. Statistical analysis used one‑way analysis of variance followed by Tukey Honestly Significant Difference test for intergroup analysis and unpaired students t‑test to compare the two methods. RESULTS: Smears prepared with both methods demonstrated atypia in 18 cases. The cellular diameter and cellular area (CA) were progressively increased from Group 1 through Groups 2 and 3 in both the smears. Nuclear diameter and nuclear area and nuclear cytoplasmic ratio progressively decreased from Group 1 through Groups 2 and 3. Both the methods showed no significant differences among the cellular parameters except in normal controls. CONCLUSION: Cytomorphometric analysis of keratinocytes obtained with oral rinse method and wooden spatula can serve as a useful screening aid to detect oral leukoplakia. Oral rinse method being more convenient results in smears of better quality.
ABSTRACT
Background: The Human Papilloma Virus (HPV) has evolved as a new culprit of malignant and pre malignant oral lesions. The objective of this study was to find out the frequency of HPV and its high risk genotypes in different lesions of oral cavity of tobacco chewers. Methods: From 492 subjects (421 males and 71 females), 20 ml of oral rinse sample was collected after obtaining an informed consent. Normal subjects with no chewing habits (250) including 135 males and 115 females were also taken from same setting. Gentle brushings over the lesions with the help of dental floss brush was done which was left in the oral rinse and stored at 4°C until DNA extraction. DNA was extracted and PCR was performed using HPV consensus primers Gp5+/Gp6+ and HPV 16, 18 specific primers for genotyping. Categorical data was calculated as frequencies and percentages. Results: Oral pre-malignant lesions were present in 421 (86%) males and 71(14%) females having leukoplakia (173, 35%), erythroplakia (60, 12%), submucous fibrosis (192, 39%) and L/E (67, 14%). Total number of HPV positives were 128 (26%), having HPV 16 (13%) and HPV 18 (11%) whereas, 76% had other genotypes. Among Submucous fibrosis 82(46%) were HPV positive. Out of total 128 HPV patients 92% were males and 8% were females. All controls were found to be HPV negative. Conclusion: Frequency of HPV was found high (26%) in oral lesions with HPV16/18 as 13% and 11% respectively. The patients with submucous fibrosis are at greater risk of having HPV. Other HPV genotypes causing premalignant lesions require further investigation.
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<b>Objective: </b>Oral mucositis is one of the serious and frequent acute side effects due to chemoradiotherapy (CRT) for head and neck cancer. In this study, we prepared an oral rinse as a hospital preparation for the treatment of oral mucositis, which was a suspension of polaprezinc (PZ), a zinc-containing therapeutic agent for gastric ulcer, in carboxyvinyl polymer (CP), a water-soluble large molecule.<br><b>Methods: </b>We carried out stability tests of the PZ-CP oral rinse, and investigated its effects on the radiation-induced oral mucositis in patients who received CRT for head and neck cancer.<br><b>Results: </b>In the stability test, the pH, viscosity, adhesion and PZ content in the preparations did not change throughout 28 days after preparation. In the clinical evaluation on the basis of the distribution of the Grade of oral mucositis, the Grade of oral mucositis in the PZ group was significantly lower than in the control group at 6 and 7 weeks (<i>p</i>=0.016, <i>p</i>=0.018). The incidence of severe oral mucositis of Grade 3 was 15.0% (3 cases) in the PZ group and 41.7% (10 cases) in the control group at 6 weeks, and was 15.0% (3 cases) in the PZ group and 33.3% (8 cases) in the control group at 7 weeks.<br><b>Conclusion: </b>These results suggest that PZ-CP oral rinse inhibits the aggravation of oral mucositis induced by CRT or promotes its healing.
ABSTRACT
<b>Objective: </b>In The Hospital of Hyogo College of Medicine, a oral rinse containing polaprezinc (PZ), a zinc-containing drug for gastric ulcers, was used as a hospital preparation to treat radiotherapy-related oral mucositis, and its efficacy was reported. However, the dispersibility of PZ for carboxymethylcellulose sodium (CMC), which was used as the base of the oral rinse, was unfavorable, raising an issue. In this study, we newly prepared a PZ oral rinse containing carboxyvinyl polymer (CP) as a base, and examined its usefulness.<br><b>Methods: </b>A questionnaire survey regarding the usefulness involving 10 healthy volunteers and a pharmaceutical test were conducted.<br><b>Results: </b>The results of the questionnaire survey showed that the optimal concentration of CP was 0.5%. There were no serial changes in the pH, adhesiveness, or PZ content for 7 days after preparation. Furthermore, there were no differences between CMC and CP. The dispersibility of PZ in the oral rinse containing CP as a base was more favorable than that in the oral rinse containing CMC.<br><b>Conclusion: </b>The results of this study suggest that the PZ oral rinse containing 0.5% CP as a base is useful, and that its stability is similar to that of the oral rinse containing CMC as a base.