The success rates of a glass ionomer cement and a resin-based fissure sealant placed by fifth-year undergraduate dental students.

AIM: To evaluate retention and caries prevention of a glass-ionomer cement (GIC) and a resin-based fissure sealant placed by fifth-year undergraduate dental students. METHODS: The study was conducted according to a split-mouth, randomised clinical trial. Children with at least one pair of caries-free permanent first molars with deep pits and fissures were included in the study. The children were selected from a population that had a high risk for dental caries. Sealant materials were applied by fifth-year undergraduate dental students on 346 fissures of the first permanent molars in 173 children. The ages of the children ranged from 7-15 years (mean 9.4). Two researchers at the clinics supervised all of the procedures. Intra-examiner reproducibility and inter-examiner reproducibility were 0.90 and 0.86, respectively, for the clinical assessment of sealant retention and caries evaluation. RESULTS: GIC sealants were completely lost in 31.9% and resin-based sealants in 16.6% (p<0.05). The total retention rates of GIC sealants and resin-based sealants were 13.8% and 20.8%, respectively. After 24 months, the caries increment was 3.4% for GIC sealants and 4.8% for resin-based sealants (p>0.05). CONCLUSIONS: The retention of GIC sealants was markedly inferior to the retention of resin-based sealants; however, GIC when used as a pit and fissure sealant was slightly more effective in preventing occlusal caries.

In vitro comparison of digital and conventional bitewing radiographs for the detection of approximal caries in primary teeth exposed and viewed by a new wireless handheld unit.

OBJECTIVES: The aim of this study was to compare the diagnostic quality of a new wireless handheld unit (ADX4000; Dexcowin Co. Ltd, Korea) on conventional bitewings and its LCD screen for the detection of approximal caries in primary teeth. METHODS: In total, 108 approximal surfaces of primary teeth were examined in vitro by 3 observers. Conventional films were viewed under subdued lighting conditions on a conventional view box. Digital 3.5 inch images were displayed on the built-in monitor of the ADX4000 and digital 17 inch images were viewed on a 17 inch monitor. The true caries diagnosis was based on histological assessment of the approximal surfaces after sectioning the primary teeth. Receiver operating characteristic (ROC) curve (A(z)) analysis was used to assess the diagnostic quality of imaging modalities. RESULTS: The areas under the ROC curves ranged from 0.786 (digital 17 inch) to 0.813 (digital 3.5 inch). No statistically significant differences were found between the three modalities for detecting approximal caries. CONCLUSIONS: It was concluded that the diagnostic quality of conventional film and digital images, which were exposed and viewed by a new wireless handheld unit, was comparable.

Penetration of radiocalcium at the margins of resin and glass ionomer dentine bonding agents in primary and permanent teeth.

OBJECTIVES: The purpose of this study was to compare the leakage of three resin dentine bonding agents (Prime and Bond, Scotchbond Multi-Purpose, Probond) and a glass ionomer dentine bonding agent (GC Fujibond LC), in cervical cavities prepared in primary and permanent molar teeth restored with a hybrid composite resin (Tetric). METHODS: Cervical cavities without a bevel at the cavo-surface margins were prepared in the buccal and lingual surfaces of extracted primary and permanent molar teeth. After being restored, the teeth were stored for 1 week in a saline solution at 37 degrees C and then thermally cycled between 5 and 55 degrees C. Marginal leakage was determined subsequently using a radioactive isotope containing 45Ca and an autoradiographic technique. RESULTS: The results revealed that there were no statistically significant differences in microleakage of the bond between permanent and primary teeth dentine and Fuji Bond LC and Probond dentine bonding agents. The difference between permanent and primary teeth groups for gingival values of the Prime and Bond 2.1 group U=22.5, p=0.0355 and the Scotchbond Multipurpose group U=24.0, p=0.0406 were statistically significant. There were no significant differences between the occlusal and gingival microleakage values in either primary or permanent teeth with Prime and Bond 2.1, Fuji Bond LC and Probond except the difference at Scotchbond Multipurpose in primary teeth. For primary teeth gingival margins, none of the bonding systems were significantly different from the control group. CONCLUSIONS: These results indicate that although no statistically significant differences were found between test and control group values, the use of Fuji II LC in cervical cavities with cementum margins in primary teeth would provide the best resistance to microleakage among the test materials while the use of Scotchbond Multi-Purpose would provide the best resistance to microleakage in cervical cavities with cementum margins in permanent teeth.

Clinical evaluation and marginal leakage of Amalgambond Plus: three-year results.

Amalgambond Plus with a high-performance additive was evaluated for its ability to bond a resin composite or an amalgam alloy to deep dentin in primary teeth with nonretentive cavity preparations. The clinical performance of amalgam and resin composite mesio-occlusodistal restorations bonded with Amalgambond Plus was evaluated at 15 months and 2 and 3 years. There was no statistically significant difference in the retention, marginal adaptation, secondary caries, and post-operative sensitivity over the times of the evaluation or between amalgam and resin composite restorations. After 3 years, most of the teeth were extracted because it was their exfoliation time, and 29 restorations limited within buccal and lingual cusps were evaluated for marginal leakage. There were no significant differences in microleakage between amalgam and resin composite restorations lined with Amalgambond Plus. Amalgambond Plus has the potential for serving successfully as a cavity liner with either amalgam or resin composite restorations.

Salivary and urinary fluoride levels after 1-month use of fluoride-releasing removable appliances.

Forty children aged 8-10 years participated in this study. Half (n =20) of them used orthodontic appliances which contained fluoride-releasing devices embedded in the lingual surface of the appliance and the other half used orthodontic appliances prepared from a fluoride-releasing acrylic polymer. Prior to the adjustment of appliances and after 1, 7, 14, 21 and 30 days salivary and urinary samples were collected and the fluoride concentrations were determined. The mean fluoride release was highest during the first week. However, the values decreased considerably after that and the curves for the two groups became parallel. The results indicate that fluoride-releasing removable appliances could be useful for a prolonged release of low concentrations of fluoride without any systemic effect.

Comparison of the effect of insertion techniques of a resin composite on dentinal adaptation of two visible light-cured bases: direct evaluation versus a replica technique.

This scanning electron microscopic study evaluated the adaptation of two visible light-cured bases, Calcimol LC and Ionoseal, to the dentinal surface after the use of various techniques to insert the resin composite material. Twenty-eight Class I cavities were prepared and restored in four groups: seven Calcimol LC and resin composite placed with a bulk or an incremental technique; and Ionoseal and resin composite placed with a bulk or an incremental technique. The specimens were sectioned longitudinally through the center of the restoration and an impression was made with a poly(vinyl siloxane) impression material. When the tooth surfaces and the impressions made from these surfaces were compared in the scanning electron microscope, extra gaps on tooth surfaces were observed that were not apparent in the impressions. These extra gaps probably resulted from desiccation of tissues; thus, the observation of replicas was useful to eliminate the inclusion of "false" gaps in the analysis. The results indicated that there was no substantial difference between Calcimol LC and Ionoseal base materials placed under resin composite inserted with an incremental technique.

Bond strength and clinical evaluation of a new dentinal bonding agent to amalgam and resin composite.

Amalgambond Plus with HPA (high-performance additive) was evaluated for its ability to bond a resin composite and an amalgam to deep primary dentin. Tensile bond strengths for resin and amalgam were 6.40 +/- 2.17 MPa and 2.95 +/- 0.92 MPa, respectively. There was a statistically significant difference between the groups. The modes of failure of the specimens were 100% adhesive for amalgam and 76% adhesive-cohesive and 24% adhesive for resin composite. The clinical performance of amalgam and resin composite mesio-occlusodistal restorations bonded with Amalgambond Plus was also evaluated over 15 months. Periapical radiographs were taken to support the clinical examination. The following parameters were assessed: marginal adaptation, secondary caries, postoperative hypersensitivity, and retention. Both types of restoration exhibited excellent marginal adaptation and retention and no secondary caries or hypersensitivity.

In vitro evaluation of fluoride uptake with application of acidulated phosphate fluoride to interproximal enamel of primary teeth using dental floss.

As a result of application of acidulated phosphate gel with a dental floss on adjoining surfaces of primary molars it has been established that there has been significant fluoride intake as compared with the control group. It has been concluded that it is an efficient method of increasing fluoride content of the primary teeth.

Comparison of electrosurgery and formocresol as pulpotomy techniques in dog primary teeth.

The primary teeth of four dogs were treated using either a conventional formocresol or electrosurgical technique following pulpotomy. Pulps of the treated teeth were evaluated histologically for the presence of inflammation, fibrosis, necrosis, resorption, and reparative dentin formation. Results indicated that conventional formocresol pulpotomy technique is histopathologically superior to electrosurgery pulpotomy technique.

Relation of ectodermal dysplasia and hypodontia.

Ectodermal dysplasia and hypodontia were diagnosed in three families who referred to Gazi University Pedodontic Department in 1989. From the view point of dentistry, it is intended to point out the genetic transitive character of ectodermal dysplasia and its possible relation with hypodontia. Also; some approaches to satisfy the patients in social and psychological aspects besides replacing the functional and cosmetic demands were carried out.