Mineralization of Dentinal Lesions with Different Concentrations of Fluoride.

Objectives: The present study aimed to investigate the relationship between fluoride concentration and mineral distribution within the dentinal lesion body. Methods: Remineralization of artificial deep dentinal lesions with various levels of fluoride was studied using a scanning electron microscope, microhardness tests, and polarized light microscope. Human molars were exposed to demineralization at pH 5.0 for 2 weeks. Then, they were divided into different groups for remineralization with different fluoride concentrations (0.1-10.0 ppm) for 1, 2, 3, and 4 weeks. Results: The results indicated a proportional relationship between fluoride concentration and dentinal lesion remineralization from 0.1 to 10.0 ppm. In the present study, the formation of a well-remineralized surface layer inhibited remineralization at the lesion front. On the other hand, the lesion front remineralization was found to be independent of fluoride concentration. Conclusion: Our results stated that for effective remineralization of dentinal lesions to the innermost part, fluoride levels from 1.0 to 5.0 ppm have the highest efficiency.

Clinical evaluation of reasons for replacement of amalgam vs composite posterior restorations.

Background: The aim of the present study is to evaluate the most common reasons for replacing posterior amalgam and resin composite restorations in patients attending the university dental restorative clinics. Methods: A total of 318 restorations which needed to be replaced were clinically and radiographically evaluated in a period of nine months. The frequencies of reasons for replacing posterior amalgam and resin composite restorations were calculated; secondary caries, restoration/tooth fracture, marginal discoloration/ditching, proximal overhang/open margin, loss of anatomy, pain/sensitivity, and esthetics. Results: The sample population comprised of 191 females and 106 males. The majority of the sample population fell in the age group of 40-50 years (n = 110). 318 restorations (n = 318) were examined in this study. 82% of examined teeth were restored with amalgam (n = 261), while posterior composite restorations comprised 18% of the examined teeth (n = 57). Among all restorations demanded to be replaced by the patients (n = 318), aesthetic need was the most common reason (n = 98), followed by Ditching or discoloration (n = 64), secondary caries (n = 57), and fracture (n = 44). Loss of anatomy was the least common cause to replace both amalgam and resin composite restorations (n = 5). The different reasons of failure were all significant between amalgam and resin composite restorations as shown in (Fig. 1) (p < 0.005). The most common reason for amalgam replacement was aesthetic. The most common reason for composite replacement was secondary caries and marginal ditching. Conclusion: Both amalgam and composite had different reasons for replacement. Amalgam had lesser risk of developing secondary caries and higher longevity than composite.

Clinical implementation of comprehending dentin on a microscopic level

SUMMARY: The aim of the present in vitro study is to visualize dentin to get an in-depth knowledge of the nature of dentin that could provide useful information regarding conditioning dentinal substrate when treating dentinal lesions. Forty-nine extracted human third molars were obtained and prepared to produce artificial dentinal lesions through demineralizing with acetic acid for 7 and 14 days, or lactic acid for 7 days. The teeth were divided into groups and treated with either NaOCl, pepsin, trypsin, or phosphoric acid. To obtain information on the morphology of the treated dentinal surfaces, all samples were visualized under high resolution field emission scanning electron microscope. With high magnification reaching x50000 dentin was clearly visualized together with its constitutes. The effect of various demineralization approaches and various treatment protocols were demonstrated clearly. The relationship between the conditioning procedure steps and the subsequent bond strength was discussed. To our best knowledge, there is no previous clear highly magnified scanning electron microscope images for dentin, and dentinal components and constitutes with and without various treatments. The current in vitro study suggests the complexity nature of dentin as a substrate that should be treated carefully especially with technique sensitive procedures such as adhesive restorations.

El objetivo del presente estudio in vitro fue visualizar la dentina para obtener un conocimiento completo de la naturaleza de ella lo que podría proporcionar información útil sobre el acondicionamiento del sustrato dentinario en el tratamiento de lesiones dentinarias. Se obtuvieron 49 terceros molares humanos extraídos y se prepararon para producir lesiones dentinales artificiales mediante desmineralización con ácido acético por 7 y 14 días, o ácido láctico por 7 días. Los dientes se dividieron en grupos y se trataron con NaOCl, pepsina, tripsina o ácido fosfórico. Para obtener información sobre la morfología de las superficies dentinarias tratadas, todas las muestras se visualizaron bajo un microscopio electrónico de barrido de emisión de campo de alta resolución. Con un gran aumento que alcanzó x50000, la dentina se visualizó claramente junto con sus componentes. Se demostró el efecto de varios enfoques de desmineralización y varios protocolos de tratamiento. Se discutió la relación entre los pasos del procedimiento de acondicionamiento y la subsiguiente fuerza de unión. Hasta donde sabemos, no hay imágenes claras previas de microscopio electrónico de barrido altamente ampliadas para la dentina y los componentes y constituyentes de la dentina con y sin diferentes tratamientos. El estudio in vitro actual sugiere la naturaleza compleja de la dentina como sustrato que debe tratarse con cuidado, especialmente en los procedimientos sensibles a la técnica, tal como las restauraciones adhesivas.

Reframing perceptions in operative dentistry relating evidence-based dentistry and clinical decision making: a cross-sectional study among Jordanian dentists.

BACKGROUND: The aim of the current study was to investigate current dental practice in operative dentistry in Jordan, and the relationship between evidence-based dentistry in caries research and decision making in clinical practice in operative dentistry. MATERIALS AND METHODS: This cross-sectional study was conducted through a survey of dentists in Jordan. The survey aimed to explore the degree of knowledge and practice of evidence-based dentistry in caries research the dentists possess regarding clinical decision making in operative dentistry. The sample size was composed of (5811) dentists whom registered in Jordan Dental Association database. Descriptive statistics were generated and Chi-square test was used to examine associations between the different variables and the significance level was set at P < 0.05. RESULTS: 4000 responses were collected from the web-survey, response rate (68.83%). Nearly half of the surveyed dentists focus on the chief complaint of their patients (n = 2032, 50.8%) rather than doing full mouth assessment. Nearly two-thirds of dentists (n = 2608, 65.2%) treat lesions confined to enamel with operative treatment. Half of dentists use operative treatment when asked about the routine management of radiographically detected proximal caries confined to enamel. When treating incipient lesions, the majority (n = 3220, 80.5%) use preventive treatment. Three-quarters of dentists (n = 2992, 74.8%) treat deep dentinal caries by removing just the soft infected carious dentin, and treated old failed restorations with replacement. CONCLUSION: In operative dentistry, the evidence-based research is not implemented clinically. To optimize relationship between evidence-based dentistry and clinical decision-making, dental curriculum has to be updated and modified constantly.

The predictive value of high school grade point average to academic achievement and career satisfaction of dental graduates.

BACKGROUND: In a country where admission to dental schools is based solely on the cognitive abilities of students, the aim of the study was to investigate the correlation between high school grade point average and graduating academic achievement for dental students; moreover, determine whether a correlation exists between dental students' graduating academic achievement and their career choices and job satisfaction. METHODS: A five-year retrospective cohort study was conducted at the University of Jordan, involving (828) dental graduates first enrolled between 2010 and 2014. Correlations comparing high school grade point average and graduating academic achievement were done for the total sample composed of (736) students. A short survey was constructed to assess the career choices and job satisfaction for recently graduated dentists and correlate them with their graduating academic achievement. RESULTS: Statistically significant but weak positive correlation (0.3) was found between high school grade point average and graduating academic achievement for dental students (p ≤ 0.05). Statistically significant correlations were found between graduating academic achievement and career choices and job satisfaction. CONCLUSION: The significant positive correlation between the high school grade point average and graduating academic achievement of our dental students indicate that our school admission system depending on high school grade point average is a valid system. There was a significant negative correlation between the graduating academic achievement and both the career choices and job satisfaction among fresh graduate dentists in Jordan. This information is required to update the dental school admissions procedures in response to the changing dental educational landscape.

Reframing Perceptions in Restorative Dentistry: Evidence-Based Dentistry and Clinical Decision-Making.

OBJECTIVES: The worldwide interest of both dentists and patients in esthetic dentistry has affected decision-making in dental practice. The aim of this study was to investigate contemporary dental practice in restorative dentistry and the relationship between evidence-based dentistry in caries research and decision-making in clinical practice in restorative dentistry. METHODS: The study was conducted through a structured questionnaire distributed randomly at the Jordanian Dental Association registered dentists in Jordan. The questionnaire aimed to clarify the degree of knowledge and practice of evidence-based dentistry in caries research the dentists hold regarding clinical decision-making in restorative dentistry. RESULTS: The majority of the surveyed dentists (77%) treat teeth with irreversible pulpitis with root canal treatment rather than vital pulp therapy. 13.8% routinely insert a post and 23% routinely crown the tooth after root canal treatment regardless of the remaining tooth structure. Badly damaged teeth are treated with full crowns in 72% of the cases. Regarding Hollywood smile or smile makeover, the majority of dentists choose conservative approaches, and implants were the first choice to replace missing teeth for 93.8% of the surveyed dentists. CONCLUSION: A higher degree of implementation of evidence-based dentistry in clinical decision-making was found in Prosthetic Dentistry than in Endodontics. Yet, the gap between evidence-based data and clinical practice needs bridging. More emphasis on communicating these data to educators to integrate them into the dental curriculum is a must.

The discoloration effect of diluted minocycline containing triple antibiotic gel used in revascularization.

BACKGROUND/PURPOSE: Triple antibiotic paste (TAP) has been successfully used in revascularization procedure. However, one of the problems associated with TAP use is teeth discoloration, which is attributed to the presence of minocycline constituent. The aim of this study is to investigate the discoloration effect of different concentrations of triple (TAP) and double (DAP) antibiotics pastes on root dentine. MATERIALS AND METHODS: Sterilized dentine specimens (4 × 4 × 1) were prepared, and randomly assigned to 5 groups; 1000 mg/mL of Triple antibiotic paste (TAP), 1000 mg/mL of Double antibiotic paste (DAP), 1 mg/mL of TAP in Methylcellulose gel (MTAP), 1 mg/mL of DAP in Methylcellulose gel (MDAP), and distilled water control groups (n = 12). The assigned treatment was applied for 14 days. The CIE L*a*b calorimetric parameters were measured for all dentine specimens using a Chroma meter. One-way ANOVA and multiple comparisons were used for statistical analyses (p < 0.05). ΔE for the different treatments as compared to distilled water group was calculated. RESULTS: TAP and MTAP groups significantly affects the L* values of the root dentine (p < 0.05). ΔE change was noticeable between TAP and MTAP compared to the distilled water group. CONCLUSION: The incorporation of minocycline in TAP medicaments, even in low concentrations, can still provoke a noticeable tooth discoloration.

The mental foramen: A cone beam CT study of the horizontal location, size and sexual dimorphism amongst living Jordanians.

Accurate information regarding the horizontal location and size of mental foramen (MF) has a well-known clinical importance. In addition, these variables have been reported to exhibit inter-population variation. The aims of the present study were to study the horizontal position and size of MF, as seen on cone beam CT (CBCT) images, and to assess sexual dimorphism in these variables. Total of 139 CBCT images of a random Jordanian sample (50 males, 89 females, average age = 43.5, SD = 13.0, range = 23-69 years) were included. The most frequent horizontal locations of MF were found to be: between the two lower premolars (50%), and in line with lower second premolar (40%). The average long diameter of MF was 3.08 mm, SD = 0.65 mm in males (n = 50, range = 1.5-4.8 mm) and 2.46 mm, SD = 0.58 mm in females (n = 89, range = 1.2-4.0 mm), and the difference was statistically significant. Very weak positive correlation was found between age and MF diameter in females (r = 0.161) and the correlation was approaching statistical significance (p-value = 0.066), while a weak negative correlation was found between these two variables in males (r = -0.276) and the correlation was statistically significant (p-value = 0.038). It could be inferred from the results of the present study that about 95% success rate for mental nerve block anesthesia is expected when the anesthetic solution is administered between the two premolars; however this needs to be tested experimentally. It appears that there is a tendency for an increase in MF size with age in females as opposed to a tendency for size reduction with age in males; this might suggest a role for sexual hormones in influencing MF size.

Evaluating Various Preparation Protocols on the Shear Bond Strength of Repaired Composite.

INTRODUCTION: The aim of this study is to evaluate the effect of different combinations of various surface treatments on the shear bond strength (SBS) of repaired composite resin. MATERIALS AND METHODS: A total of 122 composite samples were prepared from Filtek Z350 XT. Samples were light cured and stored for 6 weeks. Surface treatment of old composite was done in five groups: Group I: bur roughening + phosphoric acid etching, group II: bur roughening + hydrofluoric acid etching + silane coupling agent, group II: air abrasion + phosphoric acid etching, group IV: air abrasion + phosphoric acid etching + silane coupling agent, group V: air abrasion + hydrofluoric acid etching + silane coupling agent. Bonding agent was applied to all surface-treated old composites and light cured. The fresh composite resin was bonded to treated surfaces and cured and stored in water at 37°C for 6 weeks. Shear bond strength was measured by a universal testing machine. RESULTS: Shear bond strength values of all groups were not statistically significant except for group V, which showed statistically significant higher SBS than group III. CONCLUSION: Techniques with readily available materials at the clinic can attain similar SBS to more elaborate technique involving potentially hazardous materials.