Bond strength and micro-computed tomographic evaluation of pre-coated brackets.

OBJECTIVES: The aim of the present study was to assess and compare the shear bond strength (SBS) of metal pre-coated orthodontic brackets bonded to fluorotic and non-fluorotic teeth treated with three different etching techniques. A second aim was to determine the volume of adhesive remaining on the tooth at debond using micro-computed tomography (µCT). METHODS: Ninety extracted premolars were selected to include 45 fluorotic (test group) and 45 non-fluorotic (control group) teeth. Each group was divided into three subgroups of 15 each, which were treated as follows: 1) micro-etched; 2) acid-etched; and 3) both micro-etched and acid-etched. A bonding agent was applied to the prepared surfaces; pre-coated and light-cured brackets were attached to all teeth. An Instron universal testing machine was used to record the debonding force. Specimens were then scanned using a microCT to evaluate the amount of adhesive remaining on the teeth. The significance of the statistical tests was pre-determined at p < 0.05. RESULTS: Two-way ANOVA showed that fluorosis of teeth had no influence on the SBS (p = 0.165) whereas the volume of adhesive remnants was significantly higher in the control group compared with the test group (p < 0.001). CONCLUSIONS: Fluorosis had no influence on the SBS of brackets, whereas it had a negative influence on retaining adhesives onto the tooth surfaces.

The influence of radiation therapy on dental implantology.

Patients with a history of head and neck cancer resection require extensive prosthodontic rehabilitation following cancer treatment. The oral anatomy drastically changes from ablative therapy, and the oral tissue response becomes altered as a consequence of radiation and chemotherapy. Successful restoration of oral function in this specific patient population was increasingly difficult before the widespread use of dental implants. Implant-borne prosthetics are now often used. However, surgical guidelines remain unclear with regard to oncology-related parameters. In this article, guidelines are introduced for implant therapy in the cancer patients according to radiation dosage and timing. Indications for hyperbaric oxygen treatment are highlighted along with risk assessment associated with implant placement. These guidelines are intended to augment knowledge obtained through oncology consultation; moreover, provide a rationale for implant therapy within the course of cancer treatment.

Severity of periodontal disease in individuals chewing betel quid with and without tobacco.

BACKGROUND: The deleterious effects of chewing betel quid (BQ) with or without tobacco on periodontal health are poorly addressed. The aim of this study was to investigate the severity and extent of periodontal disease among individuals chewing BQ with and without tobacco. METHODS: One hundred twenty individuals (70 BQ chewers: 35 with tobacco and 35 without tobacco) and 50 control individuals (non-chewers) were included in this study. Sociodemographic data and information regarding BQ chewing habit were collected using a questionnaire. Plaque index, bleeding on probing and probing pocket depth were measured. Numbers of missing teeth were recorded and marginal bone loss was measured on panoramic radiographs. Statistical analyses were performed using 1-way analysis of variance and Bonferroni post hoc test. RESULTS: The socioeconomic status of subjects in the control group was significantly higher as compared with those chewing BQ either with or without tobacco. Plaque index, bleeding on probing and probing pocket depth were greater in subjects chewing BQ with tobacco than in those chewing BQ without tobacco and the controls. Subjects chewing BQ with tobacco had fewer teeth than those chewing BQ without tobacco and the controls. Marginal bone loss was higher in subjects chewing BQ with tobacco than in those chewing BQ without tobacco and the controls. CONCLUSIONS: The severity of periodontal disease is enhanced in subjects chewing BQ with tobacco as compared with those chewing BQ without tobacco. Subjects with a low socioeconomic status and poor education are significantly more likely than others to develop periodontal disease.

Role of dentifrices with essential oil formulations in periodontal healing.

INTRODUCTION: Essential oil (EO)-formulated dentifrices have significant effectiveness in reducing periodontal inflammation. This study aimed to review the role of dentifrices with EO formulations in periodontal healing. METHODS: Databases were explored from 1968 until March 2010. The focused question was what is the impact of dentifrices with EO formulations on periodontal wound healing? Databases were searched using the following terms in various combinations: "essential oil," "periodontal healing," "mouthrinse," "mouth-wash" and "periodontitis." RESULTS: Twenty studies were included. The numbers of participants ranged from 20 to 316 individuals (aged 18-70 years) and were rinsing with the EO-formulated dentifrices at least twice daily for 1 week to 48 weeks. Fourteen clinical studies showed reduced periodontal inflammatory conditions in the test group (individuals using EO dentifrices) compared with the placebo group. Three studies showed a reduction in periodontal pathogens in the test group compared with the placebo group. In 1 study, the microbiological findings remained inconclusive between the 2 groups. CONCLUSION: EO-formulated dentifrices have beneficial effects on the clinical and microbiological parameters of periodontal inflammation.

Effect of white-colored mineral trioxide aggregate in different concentrations on Candida albicans in vitro.

The antifungal action of different concentrations of white-colored mineral trioxide aggregate (MTA) against Candida albicans was assessed in vitro. Fresh mix of MTA was prepared at concentrations varying from 0.78 mg/ml to 50 mg/ml by dilution with 10 ml molten agar at 45 degrees C. The MTA-agar compound was thoroughly mixed and the uniform mix was then poured into sterile Petri dishes and allowed to set. A total of 348 agar plates were prepared and divided into experimental groups of 11 plates each and control groups of 5 plates each. Plates of agar without MTA served as positive control and plates without C. albicans served as negative control. Fresh inoculate of C. albicans was prepared by growing an overnight culture from a stock culture. Aliquots of C. albicans were then taken from the stock culture and plated on the agar compound of the experimental and positive control groups. All plates were incubated at 37 degrees C for 1, 24, 48, and 72-h periods. At each time period, the presence of C. albicans colonies was assessed and recorded. A direct correlation was found between MTA concentration and its inhibition effect on C. albicans growth. Plates containing MTA in concentration of 50 mg/ml showed significantly better killing action against C. albicans in all of the time periods tested (p < 0.001). Plates containing MTA in concentration of 25 mg/ml showed antifungal activity only at 1 and 24-h time periods. Plates containing lower concentrations of MTA did not show any antifungal activity. It appears that under the conditions of this study, white-colored MTA in concentration of 50 mg/ml is effective in killing C. albicans for periods of up to 3 days. Lower MTA concentrations may not be effective.