Impact of a Tutored Theoretical-Practical Training to Develop Undergraduate Students' Skills for the Detection of Caries Lesions: Study Protocol for a Multicenter Controlled Randomized Study

BACKGROUND

Tutored laboratorial activities could be a manner of improving the competency development of students. However, its impact over conventional theoretical classes has not yet been tested. Additionally, different university contexts could influence this issue and should be explored.

OBJECTIVE

To assess the impact of a tutored theoretical-practical training for teaching undergraduate students to detect caries lesions as compared with theoretical teaching activities. The impact of these teaching/learning activities will be assessed in terms of efficacy, cost/benefit, retention of knowledge/acquired competences, and student acceptability.

METHODS

Sixteen centers (7 centers from Brazil and 9 centers from other countries throughout the world) are involved in the inclusion of subjects for this protocol. A randomized controlled study with parallel groups will be conducted. One group (control) will be exposed to a 60- to 90-minute conventional theoretical class and the other group (test) will be exposed to the same theoretical class and also a 90-minute laboratory class, including exercises and discussions based on the evaluation of a pool of images and extracted teeth. The mentioned outcomes will be evaluated immediately after the teaching activities and also in medium- and long-term analyses. To compare the long-term outcomes, students who enrolled in the university before the participating students will be interviewed for data collection and these data will be used as a control and compared with the trained group. This stage will be a nonrandomized phase of this study, nested in the main study. Appropriate statistical analysis will be performed according to the aims of this study. Variables related to the centers will also be analyzed and used to model adjustment as possible sources of variability among results.

RESULTS

This ongoing study is funded by a Brazilian national funding agency (CNPq- 400736/2014-4). We expect that the tutored theoretical-practical training will improve the undergraduate students' performance in the detection of caries lesions and subsequent treatment decisions, mainly in terms of long-term retention of knowledge. Our hypothesis is that tutored theoretical-practical training is a more cost-effective option for teaching undergraduate students to detect caries lesions.

CONCLUSIONS

If our hypothesis is confirmed, the use of laboratory training in conjunction with theoretical classes could be used as an educational strategy in Cariology to improve the development of undergraduate students' skills in the detection of caries lesions and clinical decision-making.

Assessment of Enamel Bond Strength of Hypoplastic Primary Teeth

PURPOSE

The purpose of this study was to compare the enamel bond strength of hypoplastic and healthy primary teeth.

METHODS

Twenty-five hypoplastic teeth (experimental group) and 25 healthy primary teeth (control group) were selected and conditioned with 35 percent orthophosphoric acid before a two-layer adhesive system (Single Bond) was applied. Composite resin (Filtek Z350) was inserted in a single application, two-mm high and one-mm in diameter, and then light-cured for 20 seconds. After being stored in distilled water for 24 hours, the specimens were submitted to a shear bond strength test. Fractures were analyzed under a stereomicroscope.

RESULTS

No significant differences in bond strength were observed between the experimental group (70.27±20.40 MPa) and control group (67.84±23.37 MPa; P>0.05). However, adhesive fractures were more frequently observed in healthy teeth (72 percent) while hypoplastic teeth presented mixed fractures (60 percent) and enamel cohesive fractures (36 percent).

CONCLUSIONS

The shear bond strength of the enamel of hypoplastic primary teeth was similar to that of healthy teeth. However, distinct characteristics were observed in the dental samples following fracture.

Effectiveness of Fluorescence-based Methods in Monitoring Progression of Noncavitated Caries-like Lesions on Smooth Surfaces

Although there has been a significant decrease in caries prevalence in developed countries, the slower progression of dental caries requires methods capable of detecting and quantifying lesions at an early stage. The aim of this study was to evaluate the effectiveness of fluorescence-based methods (DIAGNOdent 2095 laser fluorescence device [LF], DIAGNOdent 2190 pen [LFpen], and VistaProof fluorescence camera [FC]) in monitoring the progression of noncavitated caries-like lesions on smooth surfaces. Caries-like lesions were developed in 60 blocks of bovine enamel using a bacterial model of Streptococcus mutans and Lactobacillus acidophilus. Enamel blocks were evaluated by two independent examiners at baseline (phase I), after the first cariogenic challenge (eight days) (phase II), and after the second cariogenic challenge (a further eight days) (phase III) by two independent examiners using the LF, LFpen, and FC. Blocks were submitted to surface microhardness (SMH) and cross-sectional microhardness analyses. The intraclass correlation coefficient for intra- and interexaminer reproducibility ranged from 0.49 (FC) to 0.94 (LF/LFpen). SMH values decreased and fluorescence values increased significantly among the three phases. Higher values for sensitivity, specificity, and area under the receiver operating characteristic curve were observed for FC (phase II) and LFpen (phase III). A significant correlation was found between fluorescence values and SMH in all phases and integrated loss of surface hardness (ΔKHN) in phase III. In conclusion, fluorescence-based methods were effective in monitoring noncavitated caries-like lesions on smooth surfaces, with moderate correlation with SMH, allowing differentiation between sound and demineralized enamel.

Oral, physical, and behavioral aspects of patient with chromosome 47, XYY syndrome

Chromosome 47, XYY syndrome is usually diagnosed late. Some of the clinical characteristics of XYY syndrome may be perceptible in dental care. The slow development of cognitive and motor activities and tall stature is common in XYY patients. The aim of this article was to relate the oral, physical, and behavioral aspects of a 6-year-old patient with the chromosome 47, XYY syndrome, diagnosed by means of karyotyping. The patient presented motor difficulty, which led to a fall and traumatism in the anterior region. In the radiography, agenesia of the permanent maxillary lateral incisors, presence of taurodontism in the primary molars, and macrodontia of the maxillary central incisors and permanent molars could be observed. Once the diagnosis was made, it was possible to understand his difficulty at school, and make available appropriate monitoring by a suitable multidisciplinary team to stimulate, control, and minimize the day-to-day difficulties found by patients with this syndrome.

Oral Manifestations and Dental Management of Epidermolysis Bullosa Simplex

Epidermolysis bullosa (EB) is a group of hereditary chronic disorders, characterized by fragility of the skin and mucous membranes in response to minor mechanical trauma. The objective of this study was to report the case of a young girl diagnosed with epidermolysis bullosa simplex (EBS), transmitted by an autosomal dominant gene. Cutaneous findings included blisters and dystrophy following minimal friction. Recurrent blisters and vesicle formation on the hard palate were the main oral findings. In conclusion, publications concerning the oral and clinical manifestations of EBS are important for providing knowledge and an early multidisciplinary approach that prevents blister formation and improves these patients' quality of life, with the dentist playing an important role in oral health management. How to cite this article: Scheidt L, Sanabe ME, Diniz MB. Oral Manifestations and Dental Management of Epidermolysis Bullosa Simplex. Int J Clin Pediatr Dent 2015;8(3):239-241.

Exposed collagen in aged resin-dentin bonds produced on sound and caries-affected dentin in the presence of chlorhexidine

PURPOSE

To evaluate the effect of chlorhexidine on the presence of collagen in aged resin-dentin bonds produced on sound and caries-affected dentin.

MATERIALS AND METHODS

Flat dentin surfaces were obtained from 16 sound molars, from which 8 were microbiologically processed for induction of caries. Single Bond 2 was applied to both sound and caries-affected substrates. In half of the teeth assigned for 6-month storage in water, the phosphoric acid demineralized dentin was impregnated with 2% chlorhexidine before the application of the adhesive. Specimens (2 x 2 x 5 mm) were produced and stored in water for 24 h, or 6 months in either water or mineral oil. The specimens were subjected to histological processing and sections were stained with Goldner's Trichrome. The thickness of the zone of exposed collagen was measured by optical microscopy and the data were subjected to two-way ANOVA and Tukey's test (α = 0.05).

RESULTS

There was no statistically significant difference (p > 0.05) between sound and caries-affected dentin regardless of the storage condition. For both substrates, significantly greater collagen exposure was observed after 6 months in water. Chlorhexidine-treated groups resulted in similar collagen exposure to that of the control and 6 months in water groups (p > 0.05), while no increase of the exposed collagen zone was observed after mineral oil storage.

CONCLUSION

Aging in water resulted in degradation of the resin-dentin bond, as demonstrated by the increase of the zone of exposed collagen. However, the degradation of the exposed collagen was decelerated in the presence of chlorhexidine.

Effect of chlorhexidine on bond strength of two-step etch-and-rinse adhesive systems to dentin of primary and permanent teeth

PURPOSE

To evaluate the influence of chlorhexidine digluconate (CHX) application on the immediate microtensile bond strength (microTBS) of two-step etch-and-rinse adhesive systems to the dentin of primary and permanent teeth.

METHODS

Noncarious human teeth (24 primary molars and 24 premolars) were used. The primary and permanent teeth were randomly assigned to three groups (n = 8) according to the adhesive system: Adper Single Bond, Prime & Bond NT and Excite DSC. Each group was further divided in two subgroups (n = 4) in which the phosphoric acid-etched dentin was treated with 20 microL of either 2% CHX or deionized water for 60 seconds prior to adhesive system application. The adhesive systems were applied according to the manufacturers' instructions and resin composite blocks were built up on the treated surfaces. The teeth were vertically sectioned perpendicular to adhesive interface and beam-shaped specimens with a 0.81 mm2 cross-sectional area were obtained and subjected to microTBS testing at a crosshead speed of 0.05 mm/minute. MicroTBS data were analyzed statistically by ANOVA and Tukey's test (alpha = 0.05). The failure modes were verified with a stereomicroscope.

RESULTS

CHX application increased significantly (P < 0.05) the microTBS of Prime & Bond NT and Single Bond to the acid-etched primary and permanent dentin, while no positive or negative effect was observed for Excite DSC. There was a predominance of adhesive failures in all control and CHX-treated groups. No fracture distribution pattern was observed.

Urgências em traumatismos dentários: classificação, características e procedimentos

OBJETIVO: Discutir os aspectos das urgências odontológicas relacionadas aos traumatismos dentários, disponibilizando mais informações para médicos pediatras ou plantonistas de serviços de atendimento de urgências e emergências. FONTES DE DADOS: O levantamento dos dados foi realizado na base de dados Pubmed e Bireme, selecionando os artigos dos últimos 13 anos. As palavras-chave utilizadas foram: traumatismo dentário, dente decíduo e dente permanente. Os critérios de inclusão utilizados foram: artigos em inglês e português sobre incidência, prevalência e etiologia, guias de procedimentos e casos clínicos apenas de traumatismo dentário, sendo excluídos artigos de clareamento de dentes traumatizados, traumas faciais ósseos e casos clínicos de acompanhamento reduzido. SÍNTESE DOS DADOS: Os dados foram descritos de forma concisa para se tornar um guia de fácil leitura e rápido acesso em relação à conduta, necessidade de atendimento imediato e correta escolha de soluções para armazenagem dos dentes e fragmentos. CONCLUSÕES: O conhecimento sobre o assunto, a agilidade no tratamento de urgência e o correto encaminhamento do paciente proporcionam melhor prognóstico.

Effect of acid etching time on the degradation of resin-dentin bonds in primary teeth

PURPOSE

To investigate the influence of etching time on the degradation of resin-dentin bonds produced in primary teeth.

METHODS

40 primary molars were randomly divided into four groups according to the adhesive system, Single Bond (SB) and Clearfil SE Bond (CSEB), and acid etching time. SB was applied to dentin after phosphoric acid etching for 15 or 7 seconds, whereas CSEB was applied after the application of SE Primer for 20 or 10 seconds. Resin composite crowns were built-up followed by the production of specimens with a cross-sectional area of 0.49 mm2, which were further divided according to the storage condition, 24 hours, 6 and 12 months in water. Data were submitted to ANOVA and Tukey tests (alpha=0.05).

RESULTS

After 24 hours there was no significant difference between bond strengths produced by the adhesive systems, irrespective of the acid etching time. Water storage for 6 and 12 months significantly reduced bond strengths of SB, especially when the dentin was acid etched for 15 seconds. For CSEB, no significant alteration in bond strength was seen up to the storage period of 12 months for both etching times.

Shortening of primary dentin etching time and its implication on bond strength

OBJECTIVE

The aim of this study was to investigate the influence of shortening the etching time on the bond strength of a conventional and a self-etching primer adhesive system used in primary tooth dentin.

METHODS

Flat dentin surfaces were obtained from 24 primary molars, randomly assigned to 4 experimental groups. The adhesive systems Single Bond and Clearfil SE Bond were applied in two groups according to the manufacturers' recommendations. In the other two groups, the adhesives were applied after half-time of acid etching, 7 s for Single Bond and 10 s for Clearfil SE Primer. Resin crowns were built up and after 24 h storage in water at 37 degrees C, the teeth were sectioned to produce beams with cross-sectional area of approximately 0.49 mm2. Specimens were tested in tension at 0.5 mm/min until failure. Fractured specimens were analyzed to determine the failure mode.

RESULTS

Tensile bond strengths for Single Bond in primary dentin were higher than for Clearfil SE Bond. Shortening of acid etching time improved bond strength only for Single Bond, while no statistically significant difference was observed for Clearfil SE Bond when both etching times were compared.

SIGNIFICANCE

No detrimental effect on bond strength was observed when the time of acid etching was shortened in 50%. Shortening the time for a procedure in a small child without compromising the quality of the work is a very important finding for the practicing pediatric dentist.