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Fulltext Comparative Study On Microleakage Of Composite Inlays Using Various Resin Luting Cements

Annuar, W.A., Abdullah, H.

Ann Dent, 2003;10(1):-.
MyJurnal

This study is conducted to compare two resin luting cements (Rely XTMARC,3M and Compolute™ESPE) on their microleakage with one composite inlay system (Filtek™ Z250 Universal Restorative Materials, 3M). Thirty conventional inlays, Class II MOIDO cavity with gingival margin I mm above the cementoenamel junction, were prepared in premolar teeth. The composite inlays were fabricated directly on the prepared teeth using layering technique. Fifteen of the inlays were cemented with RelyTMX ARC and fifteen with Compolute™ (ESPE). The specimens were kept at 370 C for 10 days before thermocycling and immersed in methylene blue 2% solution for 24 hours. The teeth were sectioned mesio-distally. The site and degree of leakage of each section was scored using a visual scoring system under a stereomicroscope at a magnification of 1.5X. Results showed that there was no significant difference in'leakage extent (p>O.05), between Rely X™ARC and Compolute™. For both materials, leakage occurred most commonly within the enamel surface and between the cement-tooth interfaces. None of the leakage occurred between inlay - cement interface. There is no significant difference in the extent of leakage between Rely XTMARC compared to Compolute™.

Matched MeSH terms: Dental Enamel
Fulltext Comparative Evaluation of Erosive Potential of Various Frozen and Unfrozen Fruit Juices on Primary Teeth Enamel: An In Vitro Study

Philip ST, Abdulla AM, Ganapathy S, Vedam V, Rajeev V

J Pharm Bioallied Sci, 2019 May;11(Suppl 2):S463-S467.
PMID: 31198388 DOI: 10.4103/JPBS.JPBS_78_19

Background: Changing lifestyle pattern and food habits has a deteriorating effect on dental tissues. Dental erosion is a pathological wear of hard tissues of teeth with increased consumption of acidic and carbonated drinks. Susceptibility to erosion in primary dentition is more compared to permanent dentition due to softer and disordered crystal structure of enamel.
Objectives: The main aim of the study was to determine and compare the erosive potential of different fruit juices in frozen/unfrozen forms on primary teeth by studying the calcium dissolution.
Materials and methods: pH of four different juices (pure) - apple, orange, citrus limetta (musumbi) and grapes were determined using a digital pH meter. The titratable acidity of these in frozen and unfrozen forms were determined by adding 0.2 ml of 1M NaOH to these to raise to pH=5.5(critical pH) and pH =7(neutral pH). Forty eight caries free deciduous anterior teeth specimens were prepared to study the calcium dissolution by atomic absorption spectrophotometer. The results were analysed for statistical significance using One-way Repeated Measures ANOVA and pair wise multiple comparison with Bonferroni correction.
Results: Total titratable acidity and calcium dissolution were found to be significantly more in the initial thawed fruit juices.
Conclusion: Frozen fruit juices had more buffering capacity and erosive potential than unfrozen forms. The study concluded that sucking on frozen fruit juices is more damaging to teeth than unfrozen forms because more of erosion is expected to occur in a frozen state.

Matched MeSH terms: Dental Enamel
Fulltext Co-Blend Application Mode of Bulk Fill Composite Resin

Al-Nabulsi M, Daud A, Yiu C, Omar H, Sauro S, Fawzy A, et al.

Materials (Basel), 2019 Aug 07;12(16).
PMID: 31394743 DOI: 10.3390/ma12162504

Objective: To evaluate the effect of a new application method of bulk-fill flowable composite resin material on bond-strength, nanoleakage, and mechanical properties of dentine bonding agents.
MATERIALS AND METHODS: Sound extracted human molars were randomly divided into: manufacturer's instructions (MI), manual blend 2 mm (MB2), and manual blend 4 mm (MB4). Occlusal enamel was removed and flattened, dentin surfaces were bonded by Prime & Bond universal (Dentsply and Optibond FL, Kerr). For the MI group, adhesives were applied following the manufacturer's instructions then light-cured. For MB groups, SDR flow+ bulk-fill flowable composite resin was applied in 2- or 4-mm increment then manually rubbed by a micro brush for 15 s with uncured dentine bonding agents and the mixture was light-cured. Composite buildup was fabricated incrementally using Ceram.X One, Dentsply nanohybrid composite resin restorative material. After 24-h water storage, the teeth were sectioned to obtain beams of about 0.8 mm2 for 24-h and thermocycled micro-tensile bond strength at 0.5 mm/min crosshead speed. Degree of conversion was evaluated with micro-Raman spectroscopy. Contraction gaps at 24 h after polymerization were evaluated and atomic force microscopy (AFM) nano-indentation processes were undertaken for measuring the hardness across the interface. Depth of resin penetration was studied using a scanning electron microscope (SEM). Bond strength data was expressed using two-way ANOVA followed by Tukey's test. Nanoindentation hardness was separately analyzed using one-way ANOVA.
RESULTS: Factors "storage F = 6.3" and "application F = 30.11" significantly affected the bond strength to dentine. For Optibond FL, no significant difference in nanoleakage was found in MI/MB4 groups between baseline and aged specimens; significant difference in nanoleakage score was observed in MB2 groups. Confocal microscopy analysis showed MB2 Optibond FL and Prime & Bond universal specimens diffusing within the dentine. Contraction gap was significantly reduced in MB2 specimens in both adhesive systems. Degree of conversion (DC) of the MB2 specimens were numerically more compared to MS1 in both adhesive systems.
CONCLUSION: Present study suggests that the new co-blend technique might have a positive effect on bond strengths of etch-and-rinse adhesives to dentine.

Matched MeSH terms: Dental Enamel
Biofilm formation of periodontal pathogens on hydroxyapatite surfaces: Implications for periodontium damage

Jaffar N, Miyazaki T, Maeda T

J Biomed Mater Res A, 2016 11;104(11):2873-80.
PMID: 27390886 DOI: 10.1002/jbm.a.35827

Biofilm formation of periodontal pathogens on teeth surfaces promotes the progression of periodontal disease. Hence, understanding the mechanisms of bacterial attachment to the dental surfaces may inform strategies for the maintenance of oral health. Although hydroxyapatite (HA) is a major calcium phosphate component of teeth, effect of biofilm formation on HA surfaces remains poorly characterized. In this study, biofilm-forming abilities by the periodontal pathogens Aggregatibacter actinomycetemcomitans Y4 and Porphyromonas gingivalis 381 were investigated on dense and porous HAs that represent enamel and dentin surfaces, respectively. These experiments showed greater biofilm formation on porous HA, but differing attachment profiles and effects of the two pathogens. Specifically, while the detachment of A. actinomycetemcomitans Y4 biofilm was observed, P. gingivalis 381 biofilm increased with time. Moreover, observations of HA morphology following formation of A. actinomycetemcomitans Y4 biofilm revealed gaps between particles, whereas no significant changes were observed in the presence of P. gingivalis 381. Finally, comparisons of calcium leakage showed only slight differences between bacterial species and HA types and may be masked by bacterial calcium uptake. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 2873-2880, 2016.

Matched MeSH terms: Dental Enamel/chemistry
Anterior tooth trauma in eleven-year-old South African children

Hargreaves JA, Matejka JM, Cleaton-Jones PE, Williams S

ASDC J Dent Child, 1995 Sep-Oct;62(5):353-5.
PMID: 8550926

Little new evidence on the prevalence of injury to the anterior teeth of children has been reported in the past five years and, in South Africa, trauma to the teeth of children in different ethnic groups has not been compared respectively. The purpose of this investigation was to determine the prevalence of dental trauma using well-defined criteria and to sample a specific age-group. Five regions were chosen and 1035 children in the eleven-year age-group were examined. No statistical significance was found between the ethnic groups related to the amount of injury sustained. For all groups, boys received more injuries than girls. The most common injury was fracture of the enamel of the maxillary central incisor. With 15 percent of the children receiving some level of trauma by age eleven years, this is one of the main dental treatment needs for South African children.

Matched MeSH terms: Dental Enamel/injuries
Fulltext An exploratory study of human teeth enamel by using FT-Raman spectroscopy

Afishah Alias, Siti Rahayu Mohd Hashim, Wajir, Julynnie, Fauziah Abdul Aziz, Mihaly, Judith

Journal of Nuclear and Related Technologies, 2009;2009(1):141-146.
MyJurnal

Unaffected, affected and heavily affected teeth enamel were studied by using FT-Raman spectroscopy. The 14 permanent teeth’s enamel surface were measured randomly, resulting in total n=43 FT-Raman spectra. The results obtained from FT-Raman spectra of heavily affected, affected and unaffected tooth’s enamel surfaces did not show any significant difference. In this study, Kruskal-Wallis and Wilcoxon rank sum tests were used to compare the intensity between the categories of enamel as well as the surfaces of teeth samples.

Matched MeSH terms: Dental Enamel
Fulltext An alternative efficient technique for thin tooth sectioning

Babar, Muneer Gohar, Gonzalez, Ma Angela

International e-Journal of Science, Medicine & Education, 2011;5(1):27-30.
MyJurnal

Background: The importance of tooth sectioning is realized in disasters such as earthquake, airplane crash investigation, terror, micro leakage studies, age estimation etc. The objective of this study was to develop a simple method to make thin sections (approximately 100 mm) from freshly extracted teeth.

Methods: One hundred and twenty human premolars recently extracted for orthodontic purpose were used for this study. The teeth were stored in 0.5% chorlaramine for 2 weeks and were not allowed to dry at any stage of the experiment. The teeth were thoroughly washed in distilled water teeth and then were sectioned buccolingually from crown to the root portion.

Results: A detailed embedding-cutting-mounting procedure is described. The prepared thin ground sections were then examined under a Polarised light microscope for the enamel and the dentine, as well as the caries lesions can clearly be distinguished.

Conclusion: This is an effective and efficient method for preparation of ground sections in which the hard tissue details are preserved.

Matched MeSH terms: Dental Enamel
Amelogenesis imperfecta: enamel ultra structure and molecular studies

Gopinath VK, Al-Salihi KA, Yean CY, Ann MC, Ravichandran M

J Clin Pediatr Dent, 2004;28(4):319-22.
PMID: 15366620

Amelogenesis imperfecta (AI) is a hereditary disorder resulting in generalized defects in the enamel. The case reported here is of a seven-year-old male child with yellow color of all his teeth. Two of his primary molars were extracted due to dental abscess with advanced root resorption. Histologically hypoplastic enamel layer, positively birefringent, generalized pitting, roughness with irregular general cracked borders were observed. Scanning electron microscope, revealed extensive irregular, disorganized rough superficial enamel layer. The enamel was irregularly decussate with filamentous prisms accompanied by small rounded formations. The morphological and histological examination of the tooth revealed that this patient has the features of AI. For genetic study blood sample were collected from the patient and PCR analysis revealed that there is no mutation in exons 1-7 of AMELX gene on the X chromosome of the patient. Hence, it is probable that the AI of this patient is not X-linked. It is more likely to be an autosomal mutation.

Matched MeSH terms: Dental Enamel/ultrastructure*; Dental Enamel Hypoplasia/pathology
Age estimation from structural changes of teeth and buccal alveolar bone level

Koh KK, Tan JS, Nambiar P, Ibrahim N, Mutalik S, Khan Asif M

J Forensic Leg Med, 2017 May;48:15-21.
PMID: 28407514 DOI: 10.1016/j.jflm.2017.03.004

Forensic odontology plays a vital role in the identification and age estimation of unknown deceased individuals. The purpose of this study is to estimate the chronological age from Cone-Beam Computed Tomography (CBCT) images by measuring the buccal alveolar bone level (ABL) to the cemento-enamel junction and to investigate the possibility of employing the age-related structural changes of teeth as studied by Gustafson. In addition, this study will determine the forensic reliability of employing CBCT images as a technique for dental age estimation. A total of 284 CBCT images of Malays and Chinese patients (150 females and 134 males), aged from 20 years and above were selected, measured and stages of age-related changes were recorded using the i-CAT Vision software. Lower first premolars of both left and right side of the jaw were chosen and the characteristics described by Gustafson, namely attrition, secondary dentine formation and periodontal recession were evaluated. Linear regression analysis was performed for the buccal bone level and the R values obtained were 0.85 and 0.82 for left and right side respectively. Gustafson's characteristics were analysed using multiple regression analysis with chronological age as the dependent variable. The results of the analysis showed R values ranged from 0.44 to 0.62. Therefore it can be safely concluded that the buccal bone level highly correlated with the chronological age and is consequently the most suitable age-related characteristic for forensic age estimation.

Matched MeSH terms: Dental Enamel/growth & development
A PCR-based sex determination method for possible application in caprine gender selection by simultaneous amplification of the Sry and Aml-X genes

Phua AC, Abdullah RB, Mohamed Z

J. Reprod. Dev., 2003 Aug;49(4):307-11.
PMID: 14967923

Sex determination of livestock is performed to achieve the objectives of livestock breeding programmes. Techniques for sex determination have evolved from karyotyping to detecting Y-specific antigens and recently to the polymerase chain reaction (PCR), which appears to be the most sensitive, accurate, rapid and reliable method to date. In this study, a PCR-based sex determination method for potential application in goat breeding programmes was developed. Primers were designed to amplify a portion of the X amelogenin gene (Aml-X) on the X chromosome to give a 300 bp product and Sry gene on the Y chromosome to give a 116 bp product. PCR optimization was performed using DNA template extracted from a whole blood sample of Jermasia goats (German Fawn x Katjang) of both sexes. It was possible to identify the sex chromosomes by amplifying both male- and female-specific genes simultaneously in a duplex reaction with males yielding two bands and females yielding one band. The Aml-X primer set, which served as an internal control primer, did not interfere with amplification of the Y-specific sequence even when a low amount of DNA (1 ng) was used. The duplex reaction subjected to a blind test showed 100% (14/14) concordance, proving its accuracy and reliability. The primer sets used were found to be highly specific and were suitable for gender selection of goats.

Matched MeSH terms: Dental Enamel Proteins/genetics