Dental erosions in subjects living on a raw food diet

The aim of the study was to investigate the frequency and severity of dental erosions and its association with nutritional and oral hygiene factors in subjects living on a raw food diet. As part of a larger dietary study 130 subjects whose ingestion of raw food was more than 95% of the total food intake were examined. The median duration of the diet was 39 (minimum 17, maximum 418) months. Before the clinical examination, the participants answered questionnaires and recorded their food intake during a 7-day period. Dental erosions were registered using study models. As a control 76 sex- and age-matched patients from our clinic were randomly selected. The raw food diet records showed the median daily frequency of ingesting citrus fruit to be 4.8 (minimum 0.5, maximum 16.1). The median intake of fruit was 62% (minimum 25%, maximum 96%) of the total, corresponding to an average consumption of 9.5 kg of fruit (minimum 1.5, maximum 23.7) per week. Compared to the control group subjects living on a raw food diet had significantly (p</=0.001) more dental erosions. Only 2.3% of the raw food group (13.2% of the controls) had no erosive defects, whereas 37.2% had at least one tooth with a moderate erosion (55.2% of the controls) and 60.5% had at least one tooth with a severe erosion (31.6% of the controls). Within the raw food group no significant correlation was found between nutrition or oral health data and the prevalence of erosions. Nevertheless, the results showed that a raw food diet bears an increased risk of dental erosion compared to conventional nutrition.

One year clinical evaluation of the retention and quality of two fluoride releasing sealants

In this prospective, double-blind, split-mouth-designed study, sealant retention rate and quality of two light-cured, fluoride-releasing sealants (Helioseal F, Fissurit F) were compared. Additionally the influence of the isolation method was evaluated. Fifty-eight subjects participated; 1 year later 54 of these (mean age 13.7 +/- 3.6 years) were reexamined. Sealants were applied to 203 tooth pairs (168 conventional and 25 invasive sealants). After 1 year, 193 tooth pairs were available for study; 82 were applied using rubber dam and 111 using cotton roll isolation. Retention rate and sealant quality were judged clinically and with photographs. The initial sealant quality was comparable for both materials. After 1 year, 53.4% of the Helioseal F sealants (44.6% of the Fissurit F sealants) were fully intact, 43.1% (51.8%) partially intact and 3.6% (3.6%) completely lost (P < 0.001). Placement under rubber dam resulted in significantly higher retention rates for both sealants (P < 0.001) as well as in an improved sealant quality. Cases of complete loss only occurred in teeth isolated with cotton rolls. The findings suggest that placement under rubber dam increases retention rate and sealant quality and may reduce material dependent factors that are considered a cause of sealant failures.

Effect of eugenol-containing temporary cements on bond strength of composite to enamel

The purpose of this study was to find out the degree to which eugenol-containing temporary cements or temporary filling materials affected shear bond strength of a dual-cure resin luting cement to acid-etched enamel. For this purpose 56 human caries-free third molars were embedded in acrylic resin and cross sectioned mesiodistally. One of the corresponding halves was covered with Temp-Bond (eugenol-containing, Group 1), Provicol (eugenol-free, Group 2), ZOE (Group 3), and eugenol (Group 4). The other half of each sectioned tooth was kept clean and served as a control. After 1 week the cements were removed; the pure eugenol group (Group 4) was terminated after 24 hours. Plastic cylinders were filled with Dual Cement and placed on the etched enamel and light cured. Shear bond strength data were recorded using a Zwick Universal Testing Machine, and the mode of failure was diagnosed using a light microscope. Significant differences in shear bond strength could neither be found between the treated halves and the controls nor among the four groups pretreated with eugenol-containing or eugenol-free temporary cements. Based on the results of this study, no adverse effects of eugenol on shear bond strength of a resin luting cement to enamel could be found.

Effect of eugenol-containing temporary cements on bond strength of composite to dentin

The effect of temporary materials on shear bond strength of composite to dentin was investigated. Sixty previously impacted (caries-free) human third molars were embedded and sectioned horizontally at the pulp chamber and at the half of the crown. The samples were covered with ZOE, Temp Bond (eugenol-containing), Fermit, (temporary resin material, used without cementing) and Provicol, (eugenol-free, calcium hydroxide-containing). All specimens were stored in saline for 10 days. After mechanical cleaning the dentin was pretreated with a dentin bonding agent (Syntac), and the composite columns were applied. Debonding was performed using a Zwick Universal Testing Machine (cross-head speed 1.5 mm/min). The mode of failure was noted using a light microscope, and the thickness of the dentin at the composite/dentin interface was measured. The median shear bond strength values for the treated and control samples were: ZOE 7.46 MPa, Temp Bond 10.22 MPa, Fermit 6.49 MPa, Provicol 8.43 MPa, and control 10.06 MPa. No two groups were significantly different at the 0.05 level (one-way ANOVA and Scheffé test). In all groups the predominant mode of failure was adhesive and there was a slight tendency towards lower shear bond strength values at lower values for the thickness of the dentin. Under the conditions described the use of eugenol-containing temporary cements had no adverse effect on shear bond strength of a dual-curing composite luting cement to dentin.

Prognosis of third molar eruption

This study was designed to find a threshold value for an increased probability of upper and lower third molar eruption measured on rotational tomograms compared with lateral cephalometric radiographs. Twenty-seven patients had been followed over a 7-year period. Space available in the retromolar region had been measured at mean ages of 13, 16, and 20 years. At early ages, patients with erupted third molars had significantly more space available in the retromolar region. More wisdom teeth had erupted with a space/width ratio > or = 1 measured on rational tomograms and a distance of 25 mm or more on lateral cephalometric radiographs. There was a strong correlation between rotational tomograms and lateral cephalometric radiograph measurements as well as good reliability and reproducibility compared with study casts.

Long-term results after maxillary advancement in patients with clefts

In order to evaluate relapse tendencies after maxillary advancement, 31 patients were examined preoperatively, postoperatively, and 1 year postoperatively; 14 of whom had clefts of the lip, alveolus, and palate. Patients with maxillary deficiency were selected in a method that mere sagittal displacement was planned. Any patients with major vertical or transverse changes or additional mandibular surgery were excluded. Treatment consisted of maxillary advancement by Le Fort I osteotomy and miniplate fixation. Besides clinical examination, skeletal and dental changes were assessed cephalometrically. Results revealed a certain relapse tendency of the displacement in the noncleft group that compared favorably to the cleft group. This relapse is dependent on the amount of advancement. Despite minor differences, the two groups did not differ significantly based on maxillary advancement, so besides advancement surgery there must be another factor, cleft, to explain the different relapse tendencies between patients with and without clefts.