Platelet preparations in dentistry: How? Why? Where? When?

The aim of this article is to review the outcomes of platelet preparations in dentistry. A structured electronic search discovered 348 articles, which described the use of autologous platelet concentrates with a relevance to clinical dentistry. Among these articles, 220 articles investigated platelet rich plasma, 99 investigated platelet rich fibrin, 22 investigated plasma rich in growth factors and 7 investigated the use of concentrated growth factors. Several studies reported beneficial treament outcomes in terms of enhanced bone and soft tissue regeneration.

Scar formation and revision after the removal of orthodontic miniscrews

Many clinicians expect complete healing after the removal of temporary anchorage devices, but clinical examination may reveal scar-like tissue. This report presents the typical features of scarring detected after the removal of miniscrews, and the clinical outcome of scar revision along with its pathologic features.

Transdisciplinary treatment of Class III malocclusion using conventional implant-supported anchorage: 10-year posttreatment follow-up

INTRODUCTION:

Combined treatment offers advantages for partially edentulous patients. Conventional implants, used as orthodontic anchorage, enable previous orthodontic movement, which provides appropriate space gain for crown insertion.

OBJECTIVE:

This case report describes the treatment of a 61-year and 10-month-old patient with negative overjet which made ideal prosthetic rehabilitation impossible, thereby hindering dental and facial esthetics.

CASE REPORT:

After a diagnostic setup, conventional implants were placed in the upper arch to anchor intrusion and retract anterior teeth. Space gain for lateral incisors was achieved in the lower arch by means of an orthodontic appliance.

CONCLUSIONS:

Integrated planning combining Orthodontics and Implantology provided successful treatment by means of conventional implant-supported anchorage. The resulting occlusal relationship proved stable after 10 years.

Cytotoxicity and genotoxicity of triethyleneglycol-dimethacrylate in macrophages involved in DNA damage and caspases activation

Triethyleneglycol-dimethacrylate (TEGDMA) is a monomer and widely used in dental composite resins. TEGDMA has been found to exhibit cytotoxicity and genotoxicity on many cells. However, little is known about the potential toxicological implications of TEGDMA on murine macrophage cell line RAW264.7. In this study, TEGDMA demonstrated a cytotoxic effect to RAW264.7 cells in a concentration- and time-dependent manner (p < 0.05). TEGDMA was found to induce two modes of cell death in a concentration-dependent manner (p < 0.05). TEGDMA-induced cell apoptosis was demonstrated by the increase in the portion of sub-G0/G1 phase and DNA ladder formation. In addition, TEGDMA exhibited genotoxicity via a dose-related increase in the numbers of micronucleus and DNA strand breaks (p < 0.05). Furthermore, the activation of caspase-3, -8, and -9 were generated by TEGDMA in a dose-dependent manner (p < 0.05). These results indicated that cytotoxicity and genotoxicity induced by TEGDMA in macrophages may be via DNA damage and caspase activation.

Areca catechu L. (Arecaceae): a review of its traditional uses, botany, phytochemistry, pharmacology and toxicology

ETHNOPHARMACOLOGICAL RELEVANCE

Areca catechu L. (Arecaceae), widely distributed in South and Southeast Asia, is a popular traditional herbal medicine that can be chewed for the purpose of dispersing accumulated fluid in the abdominal cavity and killing worms. The present paper aims to provide an up-to-date review on the traditional uses and advances in the botany, phytochemistry, pharmacology and toxicology of this plant. Furthermore, the possible trends and a perspective for future research of this plant are also discussed.

MATERIALS AND METHODS

A literature search was performed on A. catechu based on classic books of herbal medicine, PhD. and MSc. dissertations, government reports, the state and local drug standards, scientific databases including Pubmed, SciFinder, Scopus, the Web of Science, Google Scholar, and others. Various types of information regarding this plant are discussed in corresponding parts of this paper. In addition, perspectives for possible future studies of A. catechu are discussed.

RESULTS

The seeds of A. catechu (areca nut) have been widely used in clinical practice in China, India and other South and Southeast Asian Countries. Currently, over 59 compounds have been isolated and identified from A. catechu, including alkaloids, tannins, flavones, triterpenes, steroids, and fatty acids. The extracts and compounds isolated from A. catechu have many pharmacological activities. These include antiparasitic effects, anti-depressive effects, anti-fatigue effects, antioxidant effects, antibacterial and antifungal effects, antihypertensive effects, anti-inflammatory and analgesic effects, anti-allergic effects, the promotion of digestive functions, suppression of platelet aggregation, regulatory effects on blood glucose and lipids, etc. Although arecoline is the primary active constituent of A. catechu, it is also the primary toxic compound. The main toxicities of arecoline are the promotion of oral submucosal fibrosis (OSF) and cytotoxic effects on normal human cells, which involve inducing apoptosis.

CONCLUSION

As an important herbal medicine, A. catechu has potential for the treatment of many diseases, especially parasitic diseases, digestive function disorders, and depression. Many traditional uses of A. catechu have now been validated by current investigations. However, further research should be undertaken to investigate the clinical effects, toxic constituents, target organs, and pharmacokinetics and to establish criteria for quality control for A. catechu-derived medications. In addition, it will be interesting to investigate the active macromolecular compounds and active constituents other than alkaloids in both raw and processed products of A. catechu.

Tissue engineered periodontal products

Attainment of periodontal regeneration is a significant clinical goal in the management of advanced periodontal defects arising from periodontitis. Over the past 30 years numerous techniques and materials have been introduced and evaluated clinically and have included guided tissue regeneration, bone grafting materials, growth and other biological factors and gene therapy. With the exception of gene therapy, all have undergone evaluation in humans. All of the products have shown efficacy in promoting periodontal regeneration in animal models but the results in humans remain variable and equivocal concerning attaining complete biological regeneration of damaged periodontal structures. In the early 2000s, the concept of tissue engineering was proposed as a new paradigm for periodontal regeneration based on molecular and cell biology. At this time, tissue engineering was a new and emerging field. Now, 14 years later we revisit the concept of tissue engineering for the periodontium and assess how far we have come, where we are currently situated and what needs to be done in the future to make this concept a reality. In this review, we cover some of the precursor products, which led to our current position in periodontal tissue engineering. The basic concepts of tissue engineering with special emphasis on periodontal tissue engineering products is discussed including the use of mesenchymal stem cells in bioscaffolds and the emerging field of cell sheet technology. Finally, we look into the future to consider what CAD/CAM technology and nanotechnology will have to offer.

Morphologic and Demographic Predictors of Third Molar Agenesis: A Systematic Review and Meta-analysis

We aimed to consolidate all available data on worldwide third molar agenesis frequencies, with a particular emphasis on exploring the factors leading authors to find contradictory results for the demographic and morphologic predictors of this anomaly. A total of 12,376 studies were originally identified, then narrowed down to 1,312 for title/abstract screening. On the basis of our inclusion and exclusion criteria, we selected 92 studies, containing 100 effect sizes and 63,314 subjects, for systematic review and metaregression. The worldwide rate of agenesis was found to be 22.63% (95% confidence interval = 20.64% to 24.76%), although the estimates ranged from 5.32% to 56.0%. Our subgroup analyses revealed that women are 14% more likely than men to have agenesis of ≥1 third molars and that maxillary agenesis was 36% more likely than mandibular agenesis in both sexes. Furthermore, we found that having agenesis of 1 or 2 molars was most common, while agenesis of 3 or 4 molars was least common. Finally, we found large differences among agenesis frequency depending on geographic region. This information is expected to be of use not only to clinicians and patients but also to policy makers, given the implications for third molar extraction protocols.

Association between P16INK4a promoter methylation and HNSCC: a meta-analysis of 21 published studies

Background

The p16^INK4a is an important tumor suppressor gene (TSG) and aberrant methylation of promoter is known to be a major inactivation mechanism of the tumor suppressor and tumor-related genes. Aberrant TSG methylation was considered an important epigenetic silencing mechanism in the progression of head and neck squamous cell carcinoma (HNSCC). However, some studies have reported differences in the methylation frequencies of P^16INK4a promoter between cancer and the corresponding control group. Therefore, we conducted a meta-analysis to better identify the association.

Methods

PubMed, Ovid, ISI Web of Science, and EMBASE were searched to identify eligible studies to evaluate the association of p16^INK4a promoter methylation and HNSCC. Odds ratio (ORs) and 95% confidence intervals (95%CI) were calculated to evaluate the strength of association between p16^INK4a promoter methylation and HNSCC.

Results

A total of twenty-one studies with 1155 cases and 1017 controls were included in the meta-analysis. The frequencies of p16^INK4a promoter methylation in the cancer group were significantly higher than those in the control group (cancer group: median: 46.67%, range = 7.84%-95.12%; control group: median: 18.37%, range = 0–83.33%; respectively). The pooled odds ratio was 3.37 (95%CI = 2.32–4.90) in the cancer group versus the corresponding control group under the random-effects model.

Conclusion

This meta-analysis of 21 published studies identified that aberrant methylation of p16^INK4a promoter was found to be significantly associated with HNSCC.

The synergistic effects of Chinese herb and injectable calcium silicate/β-tricalcium phosphate composite on an osteogenic accelerator in vitro

This study investigates the physicochemical and biological effects of traditional Chinese medicines on the β-tricalcium phosphate (β-TCP)/calcium silicate (CS) composites of bone cells using human dental pulp cell. CS is an osteoconductive and bioactive material. For this research we have combined β-TCP and CS and check its effectiveness, a series of β-TCP/CS composites with different ratios of Xu Duan (XD) were prepared to make new bioactive and biodegradable biocomposites for bone repair. XD has been used in Traditional Chinese Medicine for hundreds of years as an antiosteoporosis, tonic and antiaging agent for the therapy of low back pain, traumatic hematoma, threatened abortion and bone fractures. Formation of bone-like apatite, the diametral tensile strength, and weight loss of composites were considered before and after immersion in simulated body fluid (SBF). In addition, we also examined the effects of XD released from β-TCP/CS composites and in vitro human dental pulp cell (hDPCs) and studied its behavior. The results show the XD-contained paste did not give any demixing when the weight ratio of XD increased to 5-10 % due to the filter-pressing effect during extrusion through the syringe. After immersion in SBF, the microstructure image showed a dense bone-like apatite layer covered on the β-TCP/CS/XD composites. In vitro cell experiments shows that the XD-rich composites promote human dental pulp cells (hDPCs) proliferation and differentiation. However, when the XD quantity in the composite is more than 5 %, the amount of cells and osteogenesis protein of hDPCs were stimulated by XD released from β-TCP/CS composites. The combination of XD in degradation of β-TCP and osteogenesis of CS gives strong reason to believe that these calcium-based composite cements may prove to be promising bone repair materials.

Can periodontal infection induce genotoxic effects?

OBJECTIVE

This study aimed to evaluate the occurrence of chromosomal abnormalities, through micronuclei, and apoptosis by the sum of karyorrhexis, pyknosis and condensed chromatin in individuals with chronic periodontitis, gingivitis associated with biofilm and no periodontal disease.

MATERIALS AND METHODS

This study included 72 individuals divided into three groups: gingivitis (n = 21), periodontitis (n = 24) and control (n = 27). Information on sociodemographic characteristics, health and lifestyle was obtained. Full mouth clinical examination was performed to define the periodontal condition. Exfoliated cells from gingival mucosa were collected for computation of micronuclei and nuclear changes indicative of apoptosis. The differences in the occurrence of endpoints (micronucleus, karyorrhexis, pyknosis and condensed chromatin) were evaluated using the conditional test to compare proportions in a rare events situation.

RESULTS

There was no statistically significant difference in the occurrence of micronucleus (p > 0.1) between gingivitis, periodontitis and control groups. The occurrence of apoptosis was significantly higher among individuals with periodontitis compared to individuals with gingivitis (p < 0.05) and controls (p < 0.025).

CONCLUSIONS

The findings showed that the inflammatory process generated by gingivitis and periodontitis is not related to a higher occurrence of chromosomal damage. However, the higher occurrence of apoptosis in individuals with periodontitis points to genotoxic effects induced by periodontal infection.

Oral tori in chronic hemodialysis patients

BACKGROUND

This study investigated the epidemiology of torus palatinus (TP) and torus mandibularis (TM) in hemodialysis patients and analyzed the influences of hyperparathyroidism on the formation of oral tori.

METHOD

During 2013, 119 hemodialysis patients were recruited for dental examinations for this study.

RESULTS

The prevalence of oral tori in our sample group was high at 33.6% (40 of 119). The most common location of tori was TP (70.0%), followed by TM (20.0%), and then both TP and TM (10.0%). Of the 40 tori cases, most (67.5%) were <2 cm in size; moreover, the majority (52.5%) were flat in shape. In symmetry, most (70.0%) occurred in the midline, followed by bilateral sides (20.0%). Notably, the levels of intact parathyroid hormone did not differ in patients with or without tori (P = 0.611). Furthermore, patients with tori did not differ from patients without tori in inflammatory variables such as log high-sensitivity C-reactive protein (P = 1.000) or nutritional variables such as albumin (P = 0.247). Finally, there were no differences between patients with and without tori in adequacy of dialysis (P = 0.577).

CONCLUSIONS

Neither hyperparathyroidism nor inflammation malnutrition syndrome was found to contribute to the formation of oral tori in chronic hemodialysis patients. Further studies are warranted.

Abnormal pregnancy outcomes in mice using an induced periodontitis model and the haematogenous migration of Fusobacterium nucleatum sub-species to the murine placenta

Objectives

To investigate if there is subspecies specific migration to the placenta by Fusobacterium nucleatum (Fn) and to determine whether experimentally induced periodontitis results in adverse pregnancy outcomes (APO) in mice.

Methods

Periodontitis was induced in pregnant mice using an inoculum of Fn and Porphyromonas gingivalis. In parallel, four sub-species of Fn were individually injected into the circulatory system. At day 18 of gestation, the placenta, liver, spleen and blood were harvested and litter size, number of viable fetuses and resorptions, maternal, fetal and placenta weights were recorded. For the direct inoculation group, some mice were allowed to deliver for assessment of length of gestation, litter size, maternal, placental and pup weight. The presence of Fn was assessed by PCR and inflammatory mediators were measured by ELISA or multiplex analysis.

Results

Mice with alveolar bone loss, a marker of periodontitis, demonstrated significantly higher fetal weights (p = 0.015) and fetal/placental weight ratios (p = 0.030). PCR analysis of maternal organs did not identify Fn in any extracted tissues. In mice that received direct injection of Fn subspecies, varying degrees of APO were observed including preterm birth, intrauterine growth restriction, and fetal loss. Haematogenous spread of only Fn subsp. nucleatum to the placenta was confirmed. Litter size was significantly smaller (p = 0.023) and the number of resorptions was higher in inoculated versus control groups. Mice injected with subsp. nucleatum had significantly increased circulating CRP levels (p = 0.020) compared to controls while the mice with induced periodontitis had increased levels of IL-6 (p = 0.047) and IL-8 (p = 0.105).

Conclusions

Periodontitis in mice elevated fetal weight and the fetal weight/placental weight ratio. This study found that subsp. nucleatum migrated haematogenously to the placenta, leading to APO in mice. The study supports the potential role of Fn in the association between periodontitis and APO.

UV-emitting upconversion-based TiO2 photosensitizing nanoplatform: near-infrared light mediated in vivo photodynamic therapy via mitochondria-involved apoptosis pathway

Photodynamic therapy (PDT) is a promising antitumor treatment that is based on the photosensitizers that inhibit cancer cells by yielding reactive oxygen species (ROS) after irradiation of light with specific wavelengths. As a potential photosensitizer, titanium dioxide (TiO2) exhibits minimal dark cytotoxicity and excellent ultraviolet (UV) light triggered cytotoxicity, but is challenged by the limited tissue penetration of UV light. Herein, a novel near-infrared (NIR) light activated photosensitizer for PDT based on TiO2-coated upconversion nanoparticle (UCNP) core/shell nanocomposites (UCNPs@TiO2 NCs) is designed. NaYF4:Yb(3+),Tm(3+)@NaGdF4:Yb(3+) core/shell UCNPs can efficiently convert NIR light to UV emission that matches well with the absorption of TiO2 shells. The UCNPs@TiO2 NCs endocytosed by cancer cells are able to generate intracellular ROS under NIR irradiation, decreasing the mitochondrial membrane potential to release cytochrome c into the cytosol and then activating caspase 3 to induce cancer cell apoptosis. NIR light triggered PDT of tumor-bearing mice with UCNPs@TiO2 as photosensitizers can suppress tumor growth efficiently due to the better tissue penetration than UV irradiation. On the basis of the evidence of in vitro and in vivo results, UCNPs@TiO2 NCs could serve as an effective photosensitizer for NIR light mediated PDT in antitumor therapy.

Usefulness of an app in improving oral hygiene compliance in adolescent orthodontic patients

OBJECTIVE

To evaluate the influence of an app-based approach in a protocol for domestic oral hygiene maintenance in a group of adolescent patients wearing fixed multibracket appliances.

MATERIALS AND METHODS

Eighty adolescent patients scheduled to start an orthodontic multibracket treatment were randomly divided into two groups of 40. Plaque index (PI), gingival index (GI), white spots (WS), and caries presence were recorded in all patients, and they were instructed regarding domestic oral hygiene maintenance on the day of braces application (t0) and every 3 months (t1, t2, t3, t4) during the first year of treatment. Study group (SG) patients were enrolled in a WhatsApp chat room-based competition and instructed to share monthly with the other participants two self-photographs (selfies) showing their oral hygiene status.

RESULTS

SG patient participation in the chat room was regular and active throughout the observation period. At t2, t3, and t4, SG patients had significantly lower values of both PI and GI and a lower incidence of new WS and caries, compared with the control group.

CONCLUSION

Integration of new "social" technologies in a standard oral hygiene motivation protocol is effective in improving compliance of adolescent patients and in improving their oral health status during orthodontic multibracket treatment.

Antibacterial coatings on titanium surfaces: a comparison study between in vitro single-species and multispecies biofilm

Dental plaque is a biofilm that causes dental caries, gingivitis, and periodontitis. Most of the studies in antibacterial coatings have been conducted by in vitro single-species biofilm formation, but oral biofilm involves more than 700 different bacterial species that are able to interact. Therefore, new studies are focused on in vitro multispecies biofilm models that mimic in vivo biofilms. The aim of the present work was to study different antibacterial coatings onto titanium surfaces and evaluate the in vitro antimicrobial properties of the surfaces on two different bacterial species and an oral biofilm. The lactate dehydrogenase assay determined that treated samples did not affect fibroblast viability. In addition, the viability of microorganisms on modified samples was evaluated by a LIVE/DEAD BacLight bacterial viability kit. Although a decrease in viable bacteria onto treated samples was obtained, the results showed differences in effectiveness when single-biofilm and oral plaque were tested. It confirms, as we expected, the distinct sensitivities that bacterial strains have. Thus, this multispecies biofilms model holds a great potential to assess antibacterial properties onto samples for dental purposes.

Fracture resistance and microleakage of endocrowns utilizing three CAD-CAM blocks

This study assessed marginal leakage and fracture resistance of computer-aided design/computer-aided manufacturing (CAD/CAM) fabricated ceramic crowns with intracoronal extensions into the pulp chambers of endodontically treated teeth (endocrowns) using either feldspathic porcelain (CEREC Blocks [CB], Sirona Dental Systems GmbH, Bensheim, Germany), lithium disilicate (e.max [EX], Ivoclar Vivadent, Schaan, Liechtenstein), or resin nanoceramic (Lava Ultimate [LU], 3M ESPE, St Paul, MN, USA).). Thirty extracted human permanent maxillary molars were endodontically treated. Standardized preparations were done with 2-mm intracoronal extensions of the endocrowns into the pulp chamber. Teeth were divided into three groups (n=10); each group was restored with standardized CAD/CAM fabricated endocrowns using one of the three tested materials. After cementation with resin cement, specimens were stored in distilled water at 37°C for one week, subjected to thermocycling, and immersed in a 5% methylene-blue dye solution for 24 hours. A compressive load was applied at 35 degrees to long axis of the teeth using a universal testing machine until failure. Failure load was recorded, and specimens were examined under a stereomicroscope for modes of failure and microleakage. Results were analyzed using one-way analysis of variance and Bonferroni post hoc multiple comparison tests (α=0.05). LU showed significantly (p<0.05) higher fracture resistance and more favorable fracture mode (ie, fracture of the endocrown without fracture of tooth) as well as higher dye penetration than CB and EX. In conclusion, although using resin nanoceramic blocks for fabrication of endocrowns may result in better fracture resistance and a more favorable fracture mode than other investigated ceramic blocks, more microleakage may be expected with this material.

The relationship between physical load and musculoskeletal complaints among Brazilian dentists

The aim of the present study was to assess the relationship between physical load and musculoskeletal complaints in dentistry and to analyze the prevalence and severity of such complaints in nine anatomical regions using a cross-sectional study of 387 dentists from Natal, Brazil. The highest prevalence of complaints was related to the lower back (58.4%) and the lowest prevalence was found in the elbow (10.3%). In general, symptoms were classified as mild because they did not cause absence due to illness. Pain complaints were associated with the following characteristics: awkward posture at work; prolonged standing or sitting; strenuous position of the upper limbs; excessive tightening of the hands during clinical treatment; and the use of vibrating tools. The results of the present study suggest a high prevalence of musculoskeletal complaints in dentists that are significantly associated with variables related to their physical workload.

Effect of toothbrushing on color changes of esthetic restorative materials

PURPOSE

The aim of this study was to evaluate the effects of various drinks and toothbrushing on the color changes of esthetic restorative materials used in pediatric dentistry.

MATERIALS AND METHODS

Forty specimens were prepared from each of three restorative materials (compomer [Dyract AP], glass ionomer cement [Ionofil Molar AC, Voco], composite resin [Filtek Z 250]). Specimens were divided into four groups for immersion in three different staining solutions (cherry juice, cola, chocolate milk) and distilled water. Each group was subdivided into brushing and non-brushing groups. The specimens in the brushing subgroups were brushed with toothpaste once a day using an electric toothbrush. Color was measured using a colorimeter, and color changes were calculated between baseline and 1, 7, 30, 60 days. Data was analyzed using Kruskal-Wallis, Mann-Whitney U, Wilcoxon, and Wilcoxon Signed Rank tests.

RESULTS

All the solutions evaluated yielded color changes, and these changes were significantly greater for composite resin than for glass ionomer cement or compomer (p < 0.006). Brushing significantly decreased the color changes of restorative materials (p < 0.004).

CONCLUSION

Brushing significantly influenced the color stability of esthetic restorative materials. The results of this study also showed that glass ionomer cements and compomers had higher color stability than composite resins.

CLINICAL SIGNIFICANCE

The color stability values after brushing may better reflect the discoloration of the esthetic restorative materials. Any color stability study model should consider the effects of toothbrushing that can remove the adsorbed colorants. The results of this study also showed that glass ionomer cements and compomers can be used in anterior restorations of children with their higher color stability than composite resins.

In vitro study of fracture strength of provisional crown materials

PURPOSE

The purpose of this report was to evaluate the effect of the fabrication method and material type on the fracture strength of provisional crowns.

MATERIALS AND METHODS

A master model with one crown (maxillary left second premolar) was manufactured from Cr-Co alloy. The master model was scanned, and the data set was transferred to a CAD/CAM unit (Yenamak D50, Yenadent Ltd, Istanbul, Turkey) for the Cercon Base group. For the other groups, temporary crowns were produced by direct fabrication methods (Imident, Temdent, Structur Premium, Takilon, Systemp c&b II, and Acrytemp). The specimens were subjected to water storage at 37℃ for 24 hours, and then they were thermocycled (TC, 5000×, 5-55℃) (n=10). The maximum force at fracture (Fmax) was measured in a universal test machine at 1 mm/min. Data was analyzed by non-parametric statistics (α=.05).

RESULTS

Fmax values varied between 711.09-1392.1 N. In the PMMA groups, Takilon showed the lowest values (711.09 N), and Cercon Base showed the highest values (959.59 N). In the composite groups, Structur Premium showed the highest values (1392.1 N), and Acrytemp showed the lowest values (910.05 N). The composite groups showed significantly higher values than the PMMA groups (P=.01).

CONCLUSION

Composite-based materials showed significantly higher fracture strengths than PMMA-based materials. The CAD-CAM technique offers more advantages than the direct technique.

Electronic apex locators may be better at determining endodontic working length than radiographs and could reduce patient radiation exposure

ARTICLE TITLE AND BIBLIOGRAPHIC INFORMATION

Clinical efficacy of electronic apex locators: Systematic review. Martins JNR, Marques M, Mata A, Carames J.J Endod 2014;40(6):759-77.

REVIEWER

Nicholas Chandler, BDS, MSc, PhD, LDSRCS, MRACDS (Endo), FDSRCPS, FDSRCSEd, FFDRCSI PURPOSE/QUESTION: The authors conducted a systematic review to compare radiographic and electronic methods of determining endodontic working length.

SOURCE OF FUNDING

The authors reported no external funding sources.

TYPE OF STUDY/DESIGN

Systematic review

LEVEL OF EVIDENCE

Level 2: Limited-quality patient-oriented evidence STRENGTH OF THE RECOMMENDATION GRADE: Grade B: Limited-quality patient-oriented evidence.

Development and validation of an instrument to assess oral health literacy in Norwegian adult dental patients

OBJECTIVE

To develop and validate an interview instrument to assess oral health literacy in Norwegian adult dental patients.

MATERIALS AND METHODS

The instrument, Adult Health Literacy Instrument for Dentistry (AHLID), was based on an OECD instrument used to assess general literacy in adults. One hundred and thirty Norwegian adults (mean age = 48 years; 57% women) participated. AHLID included a selection of oral health-related printed texts that ranged from 1-5 with respect to difficulty. A questionnaire regarding socio-demographic variables and knowledge of risk factors for oral disease was used. DMFT, stimulated salivary flow rate and streptococcus mutans and lactobacillus in saliva was also examined.

RESULTS

The Cronbach's alpha values of AHLID were 0.98 for internal consistency reliability (p < 0.01) and 0.81 for test-re-test reliability (p < 0.05). AHLID score 3 was most frequent while very few fulfilled the criteria for score 1 and 5. Linear multiple regression analysis showed that lactobacillus in saliva and knowledge of risk factors for periodontitis and caries were predictor variables of AHLID score.

CONCLUSIONS

AHLID appears to be reliable and valid to assess oral health literacy in Norwegian adults and suggests a method for country-specific health literacy instruments.

Neoformação óssea e osteointegração de biomateriais micro e nanoestruturados em ovinos

A substituição de parte do tecido ósseo se faz necessária muitas vezes na rotina cirúrgica, seja em função de fraturas, neoplasias ósseas ou enfermidades ortopédicas que acarretem em perda óssea. Neste sentido, têm se buscado biomateriais capazes de promover esta substituição, evitando o uso de enxertos ou transplantes ósseos. O objetivo deste trabalho foi avaliar a capacidade osteoregenerativa de biomateriais em diferentes composições, em tíbias de ovinos. Foram utilizadas oito ovelhas mestiças texel, com 12 meses de idade e peso médio de 28,5±7,4kg. Após adequada preparação anestésica e cirúrgica, foram produzidos três defeitos ósseos na diáfise das tíbias em sua face medial, totalizando seis defeitos de 6mm cada, sendo que quatro foram preenchidos por biomateriais, e dois por fragmentos ósseos retirados do próprio animal (autocontrole). Os materiais implantados foram: hidroxiapatita (HA), tricálcio fosfato-β (TCP-β), hidroxiapatita/tricálcio fosfato-b 60/40 (HA/TCP-b 60/40) e o nanocompósito hidroxiapatita/alumina a 5% (HA/Al2O3 a 5%). Os animais foram alocados em dois grupos: Grupo 60 (n=04), em que os animais foram eutanasiados após 60 dias da colocação dos implantes e Grupo 90 (n=04), em que a eutanásia ocorreu 90 dias após a colocação dos implantes. Foram realizadas radiografias nos períodos pré-operatório, imediatamente após o procedimento e aos 30, 60 e 90 dias de pós-operatório, a fim de excluir qualquer alteração prévia ou complicação pós-operatória, capaz de comprometer o estudo. Após a eutanásia, foram coletadas as tíbias para avaliação macro e microscópica, por meio de microscopia eletrônica de varredura (MEV) e microscopia óptica. Os resultados encontrados mostraram uma boa capacidade de neoformação óssea e uma lenta absorção da HA. O TCP-β foi rapidamente absorvido e apresentou boa capacidade osteoindutiva e osteocondutiva, sendo observada neoformação óssea no interior dos grânulos deste biomaterial. O composto bifásico HA/TCP-β (60/40) apresentou o melhor resultado a longo prazo, devido ao melhor controle na solubilização e liberação dos íons cálcio e fosfatos para o meio biológico durante o processo de neoformação óssea. O biomaterial nanocompósito HA/Al2O3 a 5% não apresentou resultados promissores neste estudo, e sugerem-se novas pesquisas a fim de investigar melhor o potencial e aplicabilidade deste novo biomaterial. Conclui-se que a hidroxiapatita, o tricálcio fosfato-β e a associação HA/TCP-β (60/40) apresentam excelente capacidade de reparação óssea, podendo ser utilizados como substitutos ósseos; a associação HA/TCP-β (60/40) é o melhor dentre os biomateriais estudados, pois apresenta velocidade de absorção intermediária em relação à HA e ao TCP-β isolados, fornecendo ainda uma sustentação adequada ao tecido neoformado; o biomaterial HA/Al2O3 5% se mostrou incompatível, provocando reação de rejeição por parte do hospedeiro e com insignificante formação de tecido ósseo, sugerindo novas pesquisas acerca deste material.

The evaluation of developmental enamel defects and dental treatment conditions in a group of Turkish children with congenital heart disease

OBJECTIVE

The aim of this study was to determine developmental enamel defects and dental treatment conditions in children with congenital heart disease by comparing them with a control group of healthy children.

METHODS

Children included in the study were referred to a paediatric dentistry for dental examination and treatment after undergoing routine examination in a paediatric clinic.

RESULTS

The congenital heart disease group included 72 children and the control group included 56 healthy children. Children in the age group of 3-14 years were included in this study. The mean age of the congenital heart disease group and control group was 6.24±2.85 and 6.73±3.01, respectively. The mean values of the decayed, missing, and filled indices for primary and permanent teeth in the congenital heart disease group were 2.80±3.77 and 0.81±1.63, respectively. In the control group, the values were 1.87±3.31 and 0.72±1.46, respectively. The care score for primary teeth was 3.6% in the congenital heart disease group and 13.3% in the control group. The enamel defect was detected in at least one permanent tooth in seven out of 72 children (9.7%) in the congenital heart disease group and in three out of 56 children (5.3%) in the control group.

CONCLUSION

Although there was no significant difference in the development of dental caries or the prevalence of enamel defects between children with congenital heart disease and healthy children, the care score was low in children with congenital heart disease. In addition, children with congenital heart disease had a higher rate of pulled primary teeth and delayed treatment of decayed teeth.

An in vivo swine study for xeno-grafts of calcium sulfate-based bone grafts with human dental pulp stem cells (hDPSCs)

The purpose of this in vivo study was to evaluate the effect of human dental pulp stem cells (hDPSCs) on various resorbable calcium sulfate/calcium phosphate bone grafts in bone regeneration. Granular particles of calcium sulfate dehydrate (CSD), α-calcium sulfate hemihydrate/amorphous calcium phosphate (α-CSH/ACP), and CSD/β-tricalcium phosphates (β-TCP) were prepared for in vitro dissolution and implantation test. The chemical compositions of specimen residues after dissolution test were characterized by XRD. The ratios of new bone formation for implanted grafts/hDPSCs were evaluated using mandible bony defect model of Lanyu pig. All the graft systems exhibited a similar two-stage dissolution behavior and phase transformation of poor crystalline HAp. Eight weeks post-operation, the addition of hDPSCs to various graft systems showed statistically significant increasing in the ratio of new bone formation (p<0.05). Null hypothesis of hDPSCs showing no scaffold dependence in bone regeneration was rejected. The results suggest that the addition of hDPSCs to calcium sulfate based xenografts could enhance the bone regeneration in the bony defect.

Effects of atmospheric pressure plasmas on isolated and cellular DNA-a review

Atmospheric Pressure Plasma (APP) is being used widely in a variety of biomedical applications. Extensive research in the field of plasma medicine has shown the induction of DNA damage by APP in a dose-dependent manner in both prokaryotic and eukaryotic systems. Recent evidence suggests that APP-induced DNA damage shows potential benefits in many applications, such as sterilization and cancer therapy. However, in several other applications, such as wound healing and dentistry, DNA damage can be detrimental. This review reports on the extensive investigations devoted to APP interactions with DNA, with an emphasis on the critical role of reactive species in plasma-induced damage to DNA. The review consists of three main sections dedicated to fundamental knowledge of the interactions of reactive oxygen species (ROS)/reactive nitrogen species (RNS) with DNA and its components, as well as the effects of APP on isolated and cellular DNA in prokaryotes and eukaryotes.

The Mechanical Properties of a Poly(methyl methacrylate) Denture Base Material Modified with Dimethyl Itaconate and Di-n-butyl Itaconate

This study investigates a wide range of clinically relevant mechanical properties of poly(methyl methacrylate) (PMMA) denture base materials modified with di-methyl itaconate (DMI) and di-n-butyl itaconate (DBI) in order to compare them to a commercial PMMA denture base material. The commercial denture base formulation was modified with DMI and DBI by replacing up to 10 wt% of methyl methacrylate (MMA) monomer. The specimens were prepared by standard bath curing process. The influence of the itaconate content on hardness, impact strength, tensile, and thermal and dynamic mechanical properties was investigated. It is found that the addition of di-n-alkyl itaconates gives homogenous blends that show decreased glass transition temperature, as well as decrease in storage modulus, ultimate tensile strength, and impact fracture resistance with increase in the itaconate content. The mean values of surface hardness show no significant change with the addition of itaconates. The magnitude of the measured values indicates that the poly(methyl methacrylate) (PMMA) denture base material modified with itaconates could be developed into a less toxic, more environmentally and patient friendly product than commercial pure PMMA denture base material.

Erosive Effect of Different Soft Drinks on Enamel Surface in vitro: Application of Stylus Profilometry

OBJECTIVE

To assess the erosive potential of various soft drinks by measuring initial pH and titratable acidity (TA) and to evaluate enamel surface roughness using different exposure times.

MATERIALS AND METHODS

The initial pH of the soft drinks (group 1: Coca-Cola; group 2: orange juice; group 3: Cedevita; group 4: Guarana, and group 5: strawberry yoghurt) was measured using a pH meter, and TA was measured by titration with NaOH. Enamel samples (n = 96), cut from unerupted human third molars, were randomly assigned to 6 groups: experimental (groups 1-5) and control (filtered saliva). The samples were exposed to 50 ml of soft drinks for 15, 30 and 60 min, 3 times daily, during 10 days. Between immersions, the samples were kept in filtered saliva. Enamel surface roughness was measured by diamond stylus profilometer using the following roughness parameters: Ra, Rq, Rz, and Ry. Data were analyzed by one-way ANOVA, Tukey's post hoc and Student-Newman-Keuls post hoc tests.

RESULTS

The pH values of the soft drinks ranged from 2.52 (Guarana) to 4.21 (strawberry yoghurt). Orange juice had the highest TA, requiring 5.70 ml of NaOH to reach pH 7.0, whereas Coca-Cola required only 1.87 ml. Roughness parameters indicated that Coca-Cola had the strongest erosion potential during the 15 min of exposure, while Coca-Cola and orange juice were similar during 30- and 60-min exposures. There were no significant differences related to all exposure times between Guarana and Cedevita. Strawberry yoghurt did not erode the enamel surface regardless of the exposure time.

CONCLUSION

All of the tested soft drinks except yoghurt were erosive. Erosion of the enamel surfaces exposed to Coca-Cola, orange juice, Cedevita, and Guarana was directly proportional to the exposure time.

An ICT based ultraselective and sensitive fluorescent probe for detection of HClO in living cells

An ICT based ultraselective and sensitive probe for colorimetric and fluorescent detection of HClOviaoxidative cleavage of an alkene linker to epoxide and then to aldehydes was developed through the conjugation of pyridinium with vanilline.

Stimulatory effects of the fast setting and suitable degrading Ca–Si–Mg cement on both cementogenesis and angiogenesis differentiation of human periodontal ligament cells

The purpose of this study is to develop a fast setting and suitable degrading Mg–calcium silicate cement (Mg–CS) and a mechanism using Mg ions to stimulate human periodontal ligament cells (hPDLCs).

Impact of basic life support training on the knowledge of basic life support in a group of Nigerian Dental Students

Aim and Objetive: The burden of cardiac arrest remains enormous globally. Early recognition and prompt and effective cardiopulmonary resuscitation are crucial to successful outcome following a cardiac arrest. This study assessed the impact of basic life support (BLS) training on the knowledge of a group of dental students.

MATERIALS AND METHODS

Sixty-eight dental students participated in this interventional study. Using convenience sampling, pre- and post-BLS training assessment were conducted with a questionnaire.

RESULTS

The mean score (standard deviation) for pretest was 4.7 (±1.47) with a range of 2-8 out a total of 10, while the mean posttest score was 8.04 ± 1.47 with a range of 3-10. The differences were statistically significant (P < 0.01). There was a marked improvement in the knowledge of the respondents with 88.2% of them having a posttest score of ≥7.

CONCLUSION

The results of this study suggest that the group of dental students' knowledge of BLS was very poor prior to the BLS training. The study also showed that the BLS training had a positive influence on the BLS knowledge of the participants.

Endodontic management of C-shaped root canal system of mandibular first molar by using a modified technique of self-adjusting file system

AIM

C-shaped canal system is a seldom-found root canal anatomy which displays a challenge in all stages of endodontic treatment. According to the literature, this type of canal morphology is not a common finding in the mandibular first molar teeth.

BACKGROUND

This case report presents endodontic management of a mandibular first molar with a C-shaped canal system.

CASE REPORT

Root canal system was cleaned and shaped by nickel-titanium (NiTi) rotary instruments combined with self-adjusting file (SAF). Obturation was performed using warm, vertical condensation combined with the injection of warm gutta-percha. Follow-up examination 12 months later showed that the tooth was asymptomatic. The radiological findings presented no signs of periapical pathology.

CLINICAL SIGNIFICANCE

The clinician must be aware of the occurence and complexity of C-shaped canals in mandibular first molar teeth to perform a successful root canal treatment. The supplementary use of SAF after application of rotary instruments in C-shaped root canals might be a promising approach in endodontic treatment of this type of canal morphology.

Periodontal health during clear aligners treatment: a systematic review

BACKGROUND

Clear aligner treatment (CAT) has been cited as a safe and comfortable orthodontic procedure for adult patients. However, the available evidence is scarce.

OBJECTIVE

To perform a systematic review of the existing literature in order to assess periodontal health during CAT.

SEARCH METHODS AND SELECTION CRITERIA

Pubmed, Pubmed Central, National Library of Medicine's Medline, Embase, Cochrane Central Register of Controlled Clinical trials, Web of Knowledge, Scopus, Google Scholar, and LILACS were searched from January 1945 to September 2014 to identify all peer-reviewed papers potentially relevant to the review.

DATA COLLECTION AND ANALYSIS

After duplicate selection and extraction procedures, the risk of bias was assessed according to the Centre for Reviews and Dissemination criteria, and a 3-point grading system, as described by the Swedish Council on Technology Assessment in Health Care (SBU), was used to rate the methodological quality of the selected papers. A PICOS table was used for data extraction.

RESULTS

Five relevant articles were selected from the 1247 identified articles. The level of evidence was moderate for all the studies. A significant improvement of the periodontal health indexes was revealed, in particular when CAT was compared to fixed appliances. No periodontal CAT adverse effects were observed in the selected studies.

CONCLUSIONS

Periodontal health indexes were significantly improved during CAT. The results of this review should be interpreted with some caution because of the number, quality, and heterogeneity of the included studies.

p-Cresol affects reactive oxygen species generation, cell cycle arrest, cytotoxicity and inflammation/atherosclerosis-related modulators production in endothelial cells and mononuclear cells

AIMS

Cresols are present in antiseptics, coal tar, some resins, pesticides, and industrial solvents. Cresol intoxication leads to hepatic injury due to coagulopathy as well as disturbance of hepatic circulation in fatal cases. Patients with uremia suffer from cardiovascular complications, such as atherosclerosis, thrombosis, hemolysis, and bleeding, which may be partly due to p-cresol toxicity and its effects on vascular endothelial and mononuclear cells. Given the role of reactive oxygen species (ROS) and inflammation in vascular thrombosis, the objective of this study was to evaluate the effect of p-cresol on endothelial and mononuclear cells.

METHODS

EA.hy926 (EAHY) endothelial cells and U937 cells were exposed to different concentrations of p-cresol. Cytotoxicity was evaluated by 3-(4,5-Dimethylthiazol-2-yl)-2,5 -diphenyltetrazolium bromide (MTT) assay and trypan blue dye exclusion technique, respectively. Cell cycle distribution was analyzed by propidium iodide flow cytometry. Endothelial cell migration was studied by wound closure assay. ROS level was measured by 2',7'-dichlorofluorescein diacetate (DCF) fluorescence flow cytometry. Prostaglandin F2α (PGF2α), plasminogen activator inhibitor-1 (PAI-1), soluble urokinase plasminogen activator receptor (suPAR), and uPA production were determined by Enzyme-linked immunosorbant assay (ELISA).

RESULTS

Exposure to 100-500 µM p-cresol decreased EAHY cell number by 30-61%. P-cresol also decreased the viability of U937 mononuclear cells. The inhibition of EAHY and U937 cell growth by p-cresol was related to induction of S-phase cell cycle arrest. Closure of endothelial wounds was inhibited by p-cresol (>100 µM). P-cresol (>50 µM) also stimulated ROS production in U937 cells and EAHY cells but to a lesser extent. Moreover, p-cresol markedly stimulated PAI-1 and suPAR, but not PGF2α, and uPA production in EAHY cells.

CONCLUSIONS

p-Cresol may contribute to atherosclerosis and thrombosis in patients with uremia and cresol intoxication possibly due to induction of ROS, endothelial/mononuclear cell damage and production of inflammation/atherosclerosis-related molecules.

Osseous choristoma of the tongue: a review of etiopathogenesis

Osseous choristoma is a normal bone tissue in an ectopic position. In the oral region lingual localization occurs more frequently and the mass is generally localized on the dorsum of the tongue. Definitive diagnosis is obtained only after histopathologic examination. The etiology remains already debatable. The treatment of choice is surgical excision. In this paper we present a case of tongue osseous choristoma and a review of the literature.

Measuring oral health literacy: a scoping review of existing tools

BACKGROUND

This article presents findings from a scoping review of tools used to measure oral health literacy. Internationally, interest in oral health literacy is driven by oral health disparities, particularly for disadvantaged groups, with conditions such as dental caries and periodontal disease contributing substantially to the global burden of disease. The increasing focus on measuring oral health literacy aligns with reasons for measuring broader health literacy, that is, by assessing oral health literacy, decisions can be made about instigating interventions at policy and practice level to improve individual and population level oral health. There are numerous tools available that measure oral health literacy using a range of indicators.

METHODS

A scoping review was designed to map the existing tools designed to measure oral health literacy (OHL). Key search terms were developed and mapped. Selected databases were used that identified 32 relevant studies reporting a range of OHL tools.

RESULTS

We identified 32 articles that reported a range of oral health literacy tools. Many of the studies used the Rapid Estimate of Adult Literacy in Dentistry (REALD) and/or the Test of Functional Health Literacy in Dentistry (ToFHLiD) that were developed from earlier tools designed to measure broader health literacy. These tools have been widely criticised for providing only an approximate measure of OHL based mainly on word recognition. A number of newer tools have included new measures of oral health literacy including numeracy and oral health conceptual knowledge however tools that measure important indicators of oral health literacy such as service navigation are rare.

CONCLUSIONS

Findings from this scoping exercise confirm our findings from preliminary scans that the majority of tools are heavily biased towards word recognition, numeracy and reading skills, rather than what this means in terms of health behaviours and service utilisation. More recent developments have attempted to incorporate other aspects considered important, including decision making and service navigation. The incorporation of these aspects into newer tools will provide oral health researchers and policy makers with further evidence of the importance of oral health literacy when designing interventions to improve oral health.

Novel tea polyphenol-modified calcium phosphate nanoparticle and its remineralization potential

Tea polyphenols (TP) are not only potent antimicrobial and antioxidant agents but also effective modifiers in the formation of nanosized crystals. Since nano-hydroxyapatite (n-HA) is known to enhance remineralization of dental hard tissue, our aims were to synthesize nanosized calcium phosphate particles incorporating TP and to test their potential as caries preventive agent. An ammonia water diffusion method was used to synthesize nanosized calcium phosphate particles (TP-CaP) in the presence of various amounts of TP. The resultant products were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD). The remineralization potential of the nano TP-CaP was then investigated in a 12-day pH-cycling model. Nano TP-CaP slurries, at pH 7.0 and pH 5.5, were applied onto preformed enamel lesions 4 × 3 min per day. n-HA slurries at pH 7.0 and pH 5.5 were used as positive controls, and deionized water was served as a negative control. SEM showed nanosized particles were only formed at 27 mg/mL of TP. Further characterization of the nanosized particles revealed the components were amorphous calcium phosphate, HA, and TP. Both surface microhardness and transverse microradiography analyses showed that nano TP-CaP at pH 5.5, but not at pH 7.0, significantly enhanced remineralization, to the same extent as the n-HA controls. Furthermore, significantly higher amount of TP was found in the supernatant of TP-CaP at pH 5.5 than those at pH 7.0. Since TP can inhibit bacterial growth and enzyme activities, the novel nanosized TP-CaP particle, at low pH, is a potential dual-functional-remineralization and antibacteria-product.

Evaluation of a Russian version of the oral health literacy instrument (OHLI)

Background

Oral health literacy has become a popular research area in the last decade; however, to date no health literacy instruments in the Russian language exist. The objectives of this study were to develop a Russian version of the Oral Health Literacy Instrument (OHLI) and to examine its reliability and validity.

Methods

A convenience sample of patients who visited the dental division of the district hospital in Belarus was used in the study. The OHLI, created originally in English, was modified to adapt it to characteristics of routine dental services in Belarus and then translated into Russian, followed by back-translation. Participants completed a self-administered socio-demographic questionnaire, an oral health knowledge test and the Russian version of the OHLI (R-OHLI). Bivariate and multivariate statistical analyses, including multiple regression modeling, were performed to examine reliability and validity of the R-OHLI.

Results

Participants were 281 adult patients aged from 18 to 60 years, with a mean age of 33.1 ± 12.2; 64.1% of them were women. Cronbach’s alpha values for the two sections (reading comprehension and numeracy) and the total R-OHLI were 0.853, 0.815 and 0.895, respectively. The mean total R-OHLI score was 77.2 ± 14.5; the mean reading comprehension and numeracy scores were 39.5 ± 7.5 and 37.8 ± 8.8, respectively. The R-OHLI was significantly correlated to the oral health knowledge test. Pearson’s correlation coefficients between the oral health knowledge test and the reading comprehension, numeracy and total R-OHLI were 0.401, 0.258, and 0.363, respectively (p < 0.001). Women, participants with a university degree, and those who visited a dentist at least once a year had significantly (p < 0.05) higher mean scores for each section (reading comprehension, numeracy) and for total R-OHLI compared to their counterparts.

Conclusions

The R-OHLI showed good internal consistency and test-retest reliability. It was significantly associated with the oral health knowledge test, socio-demographic and behavioral factors. Therefore, the R-OHLI was proved to be a reliable and valid oral health literacy instrument for Russian-speaking people.