Oral events related to low-dose methotrexate in rheumatoid arthritis patients

Low-dose methotrexate (MTX) is frequently used for patients with rheumatoid arthritis (RA). High doses of MTX frequently produce side effects. The aim of this study was to explore oral complications of low-dose MTX therapy in a population of RA patients. This is a cross-sectional study in which oral examination was performed on a population of RA patients. Patients undergoing MTX therapy (5-20 mg weekly) for at least six months were included in the study group, and RA patients being treated under another regimen were used as controls. The frequency of oral lesions was compared between groups. The chi-square test was used to compare frequencies. Relative risk (RR) and its confidence interval (CI) were established. Significance level was set at 0.05. Twenty-eight RA patients on a low-dose MTX regimen and 21 controls were enrolled in the study. Oral lesions were found in 22 patients (78.6%) undergoing MTX therapy, and in 5 patients (23.8%) undergoing other therapies (p < 0.001). There were no significant differences regarding age, gender or dosage. The most common oral events observed in patients in the MTX group were ulcerative/erosive lesions (60.7%) and candidiasis (10.7%). Patients in the control group presented lower prevalence of the same lesions (p < 0.001). The RR for developing oral lesions was 11.73 (CI 2.57 - 58.98), with low-dose MTX therapy. In conclusion, the prevalence of oral mucosa lesions in RA patients receiving low doses of MTX therapy is higher than in RA patients not receiving the drug.     

Diclofenac in hyaluronic acid gel: an alternative treatment for actinic cheilitis

Objective

Actinic cheilitis (AC) is a precancerous lesion of the lip vermillion caused by prolonged exposure to ultraviolet light. The aim of this study was to evaluate the effect of 3% diclofenac in 2.5% hyaluronic acid gel in the treatment of AC.

Methods

Thirty-four patients with chronic AC were treated twice a day with topical diclofenac during a period of 30 to 180 days. The individuals were followed up every 15 days by means of clinical examination and digital photographic documentation.

Results

Of the 27 patients that completed the study, 12 (44%) showed complete remission of the whitish plaques and exfoliative areas, and 15 (56%) had partial remission of the clinical picture of cheilitis. The latter group was submitted to excision of the leukoplakic areas which diagnosis varied from mild to moderate epithelial dysplasia.

Conclusion

The results suggest a promising role for diclofenac in hyaluronic acid gel in the treatment of AC. This treatment has the advantages of not being invasive and showing few side effects.     

Synthesis and biocompatibility of an experimental glass ionomer cement prepared by a non-hydrolytic sol-gel method

The aims of this study were to demonstrate the synthesis of an experimental glass ionomer cement (GIC) by the non-hydrolytic sol-gel method and to evaluate its biocompatibility in comparison to a conventional glass ionomer cement (Vidrion R). Four polyethylene tubes containing the tested cements were implanted in the dorsal region of 15 rats, as follows: GI - experimental GIC and GII - conventional GIC. The external tube walls was considered the control group (CG). The rats were sacrificed 7, 21 and 42 days after implant placement for histopathological analysis. A four-point (I-IV) scoring system was used to graduate the inflammatory reaction. Regarding the experimental GIC sintherization, thermogravimetric and x-ray diffraction analysis demonstrated vitreous material formation at 110oC by the sol-gel method. For biocompatibility test, results showed a moderate chronic inflammatory reaction for GI (III), severe for GII (IV) and mild for CG (II) at 7 days. After 21 days, GI presented a mild reaction (II); GII, moderate (III) and CG, mild (II). At 42 days, GI showed a mild/absent inflammatory reaction (II to I), similar to GII (II to I). CG presented absence of chronic inflammatory reaction (I). It was concluded that the experimental GIC presented mild/absent tissue reaction after 42 days, being biocompatible when tested in the connective tissue of rats.     

Influence of the degree of dentine mineralization on pulp chamber temperature increase during resin-based composite (RBC) light-activation

Objectives

To analyse the influence of the degree of dentine mineralization on the pulp chamber temperature increase during composite light-activation.

Methods

Dentine discs (2 mm thick) obtained from recently extracted teeth or those with extensive dentine sclerosis were analysed by FT-IR spectrometry in order to choose the two discs with the greatest difference in the degree of mineralization. A model tooth was set up with the dentine discs between a molar with the pulp chamber exposed and a crown with a standardized class II cavity. A K-type thermocouple was introduced into the molar root until it came into contact with the dentine discs and the cavity was filled with P60 resin composite. The temperature rise was measured for 120 s after light-activation began: Standard (S) 600 mW/cm²/40 s; Ramp (R) 0 → 800 mW/cm²/10 s + 800 mW/cm²/10 s; Boost (B) 850 mW/cm²/10 s and LED (L) 1.300 mW/cm²/40 s (n = 10). The same protocol was repeated after grinding the dentine discs to 1.0 and 0.5 mm thickness.

Results

The temperature increase was significantly higher in dentine with high degree of mineralization (p < 0.05). With respect to the dentine thickness, the following result was found: 2 mm < 1 mm < 0.5 mm (p < 0.05). The light-activation mode also presented significant difference as follows: S > R = L > B (p < 0.05).

Conclusions

The higher the degree of dentine mineralization the greater the increase in pulp chamber temperature. The temperature increase was influenced by the light-polymerization mode and dentine thickness.     

Bonding properties of universal adhesives to root canals prepared with different rotary instruments

Statement of problem

Preparation of coronal dentin by using a diamond rotary instrument usually results in higher bond strength values than preparation with tungsten carbide burs, but information is lacking about the influence of rotary instruments on root canals before the bonding of fiber posts.

Protection of short-time enamel erosion by different tetrafluoride compounds

OBJECTIVE: This in vitro study aimed to analyse the protective effect of differently concentrated titanium (TiF(4)), zirconium (ZrF(4)) and hafnium (HfF(4)) tetrafluoride on enamel erosion. METHODS: Polished enamel surfaces of 36 bovine crowns were covered with tape leaving 4 enamel windows each 3mm in diameter exposed. The crowns were randomly assigned to six groups (each n=6) and pretreated with 4% TiF(4), 10% TiF(4), 4% ZrF(4), 10% ZrF(4), 4% HfF(4) or 10% HfF(4) for 4 min (first window), 10 min (second window) or 15 min (third window). The fourth window of each crown was not pretreated and served as control. Erosion was performed stepwise with 1% HCl (pH 2) in five consecutive intervals of each 15 s (total 75 s). Enamel dissolution was quantified by colorimetric determination of phosphate release into the acid. For each tooth, cumulative phosphate loss of enamel pretreated with one of the tetrafluoride compounds was calculated as percentage of the respective control and statistically analysed using two-way ANOVA. RESULTS: Enamel erosion was significantly reduced by TiF(4), ZrF(4) and HfF(4) application. Cumulative phosphate loss (mean % of control, 75s erosion) after 4-15 min application was significantly lower for 4% ZrF(4) (7-11%), 10% ZrF(4) (2-6%), 4% HfF(4) (11-9%) and 10% HfF(4) (12-16%) compared to 4% TiF(4) (42-27%) and 10% TiF(4) (54-33%). Only for 4% and 10% TiF(4), phosphate loss decreased with increasing duration of application, but also increased with increasing acid intervals. CONCLUSION: TiF(4), ZrF(4) and HfF(4) might protect enamel against short-time erosion, but protection was more enhanced by ZrF(4) and HfF(4) compared to TiF(4) application overtime.     

In vitro evaluation of frictional forces between archwires and ceramic brackets.

The aim of this study was to evaluate the frictional force between orthodontic brackets and archwires. The differences in magnitude of the frictional forces generated by ceramic brackets, ceramic brackets with metal reinforced slot, and stainless steel brackets in combination with stainless steel, nickel-titanium, and beta-titanium orthodontic archwires were investigated. Brackets and wire were tested with tip angulations of 0 degrees and 10 degrees. Friction testing was done with the Emic DL 10000 testing machine (S?o José do Rio Preto, PR, Brazil), and the wires were pulled from the slot brackets with a speed of 0.5 cm/min for 2 minutes. The ligation force between the bracket and the wire was 200 g. According to the data obtained, the brackets had frictional force values that were statistically significant in this progressive order: stainless steel bracket, ceramic bracket with a metal reinforced slot, and traditional ceramic bracket with a ceramic slot. The beta-titanium wire showed the highest statistically significant frictional force value, followed by the nickel-titanium and the stainless steel archwires, in decreasing order. The frictional force values were directly proportional to the angulation increase between the bracket and the wire.     

Esthetic alternative for fluorosis blemishes with the usage of a dual bleaching system based on hydrogen peroxide at 35%

Esthetic dental procedures in pediatric dentistry represent sources of satisfaction and realization, as much for the patient as for the professional. Lack of dental esthetics may develop psychological problems in infant as well as in adolescent patients. Blemishes produced by fluorosis appear as a challenge to the pediatric dentist and alternatives for treatment are desired. The scope of this present paper is to relate a clinical case with esthetic solution for blemishes in teeth enamel due to fluorosis. A dual system of bleaching was used (photo/chemically activated) based on hydrogen peroxide at 35% (Hi-Lite-Shofu) in a male eight-year-old patient with white fluorosis blemishes on teeth 11 and 21. The bleaching system used was efficient in bleaching teeth with white blemishes due to fluorosis, thus masking the blemishes and providing a more uniform appearance.     

Cervical impalement injury

Impacted injuries of the head and neck are uncommon. Associated injuries can be present and can be a serious problem. We present an unusual clinical case and discuss the management of this complex injury. Head and neck injuries deserve special attention because of their enormous functional and esthetic significance. Contusion, abrasion, retained foreign bodies, laceration, and avulsion are some of the most frequent injuries. Impalement injuries are not so common. These lesions combine aspects of blunt and penetrating trauma and usually result from penetration by a large, rigid, blunt-tipped object that traverses a certain body area in a through-and-through fashion and often remains in situ at the time of presentation. There have been many case reports describing these injuries in the trunk and extremities; however, cases of head and neck impalement are still lacking in number. A case of an unusual cervical impalement is presented, together with a discussion of the management of this complex injury.