Caries-affected Teeth Research Articles

Flavonoids modulate regenerative-related cellular events in LPS-challenged dental pulp cells

ObjectiveTo investigate the effects of quercetin (QU), hesperetin (HT), and taxifolin (TX) on human dental pulp cells (hDPCs) chronically exposed to lipopolysaccharide (LPS). MethodsFirst, the cytotoxicity (alamarBlue) and bioactivity (biomineralization, Alizarin Red) of QU, HT, and TX concentrations were evaluated on healthy hDPCs. Then, the effects of non-cytotoxic and bioactive concentrations were investigated on hDPCs after previous stimulation with E. coli LPS (10 µg/mL) for 7 days. Cell culture media with and without LPS were used as positive and negative controls, respectively. Cell viability (alamarBlue), NF-κB activation (immunofluorescence), reactive oxygen species production (ROS, H2DCFDA probe), cell migration (Transwell), inflammatory gene expression (RT-qPCR), and odontogenic differentiation (RT-qPCR and alizarin red) were evaluated (n=8). Data were analyzed using confidence intervals and ANOVA (α=5%). ResultsThe concentrations of 20 µM QU, 20 µM HT, and 200 µM TX reduced cell viability by more than 30%. The 5 µM QU, 10 µM HT, and 100 µM TX concentrations were cytocompatible and stimulated biomineralization by healthy hDPCs. These concentrations were tested under the LPS challenge, and cell viability and odontogenic differentiation were significantly increased, while ROS production and inflammatory response were significantly decreased. In addition, the flavonoids significantly stimulated cell migration, reduced NF-κB activation, and increased biomineralization by LPS-challenged hDPCs compared to cells exposed to LPS alone and without any other treatment. ConclusionFlavonoids can modulate the metabolism of hDPCs chronically exposed to LPS in vitro, stimulating cellular events compatible with stem cell-based regenerative processes. Clinical SignificanceFlavonoids may be explored as adjuvant therapeutic agents during pulp capping to counteract chronic inflammatory conditions and stimulate regeneration of the dentin-pulp complex in caries-affected teeth, thereby preserving tooth vitality.

Differential analysis of the dentin soluble proteomic

ObjectivesTo perform a differential analysis of the dentin soluble proteomic and assess the effects of tissue health state and protocol for protein extraction. We hypothesized the dentin soluble proteomic varies according to the tissue physiopathological state (intact vs. caries-affected) and protocol used to extract its proteins. MethodsDentin from freshly extracted non-carious and carious teeth were randomly assigned for protein extraction using either guanidine-HCl/ethylenediaminetetraacetic acid (EDTA) or acetic acid. Protein extracts from intact and caries-affected dentin were processed and digested with trypsin for shotgun label-free proteomic analysis (nLC-ESI-MS/MS). Peptides identification was performed on a nanoACQUITY UPLC-Xevo Q-Tof MS system. Peptides identified with scores of confidence greater than 95% were included in the quantitative statistical analysis embedded in the PLGS software. Differences between experimental conditions were calculated using Student test-t with significance pre-set at α=0.05. ResultsA total of 158 human proteins were identified. Approximately one-sixth of proteins (24/158) were present in at least two different extracts. Conversely, the greatest number of proteins (134/158) was identified uniquely in only one of the extracts. Overall, a larger number of soluble proteins was retrieved from caries-affected than intact dentin (86/158). Likewise, a greater number of proteins was extracted by the guanidine-HCl/EDTA (106/158) in comparison to acetic acid protocol. Several proteins detected in dentin extracts, mainly those from caries-affected teeth, are biological and/or metabolically involved with tissue turnover/remodeling. ConclusionThe identity/abundance of soluble proteins retrieved from and remained in dentin noticeably depend on this tissue physiopathological state and protocol used to remove its minerals. Clinical significanceThe present findings brought new insight into the proteomic phenotype of human dentin and may provide targets for the development of novel caries disease-prevention therapies.

AFFECTION ON CARIES AND ITS COMPLICATIONS OF TEMPORARY TEETH OF CHILDREN IN A REGION WITH EXCESS FLUORINE CONTENT IN DRINKING WATER.

Aim: The aim of the study was to determine the indicators of caries and its complications in the temporary teeth of children who permanently live in a region with a high fluoride content in drinking water. Materials and Methods: It was examined with the definition of caries and its complications 277 children in the age range from 2 to 13 years, who were born and permanently live in the urban-type settlement of Mashivka. The fluoride content in the drinking water of the settlement was 1.7-2.5 mg/l. Results: During the analysis of data from the survey of children who were born and permanently lived in the urban-type settlement of Mashivka, it was determined that the prevalence of caries of temporary teeth probably increases with age. Half of the 3-5-year-old children had caries-affected teeth, and temporary tooth caries reached the highest rates in 10-year-old children. It should be noted that a fifth of children in the youngest age group (3-5 years old) suffer from pulpitis and periodontitis of temporary teeth. Conclusions: The conducted examination of children urban-type settlement of Mashivka confirms the opinion that the excessive content of fluorine in drinking water does not have a caries-protective effect, and the intensity of the process reaches the indicators characteristic of regions with its optimal content. Such a situation requires strengthening measures for both primary and secondary prevention of dental diseases.

INDICATORS OF CARIES OF PERMANENT TEETH TAKING INTO ACCOUNT THE DEGREE OF ITS ACTIVITY IN ADOLESCENTS STUDYING IN DIFFERENT EDUCATIONAL INSTITUTIONS

In recent years, there has been noted a tendency to deterioration of dental health in children and teenagers. Therefore, it is important to study the dental status of children who attend different educational establishments to identify risk factors for dental diseases and develop means of their elimination.
 The survey of adolescents studying in various educational institutions (school, college, university) in Chernivtsi was conducted according to the generally accepted method. The study of the prevalence (%) and intensity of caries (CPV of teeth) was taking into account the degree of caries activity in each age period: compensated (1st), subcompensated (2nd), decompensated (3rd). A total of 107 schoolchildren, 317 college students, and 116 university students were surveyed. Adolescents are 15 to 18 years old. To conduct the study, the average rates of caries in each age group were calculated to determine the degree of caries activity in each age period, taking into account the area where adolescents live. The following indicators were obtained for the Chernivtsi region:
 – 15 years: compensated form – up to 4 caries-affected teeth, subcompensated – 5-7, decompensated – 8 or over;
 – 16 years: compensated – up to 5, subcompensated – 6-8, decompensated – 9 or over;
 – 17 years: compensated – up to 7, subcompensated – 8-10, decompensated – 11 or over;
 – 18 years: compensated – up to 8, subcompensated – 9-11, decompensated 12, or over.
 Our research showed that college students in all studied age periods (15, 16, 17, and 18 years) had worse results than teenagers in the comparison groups (schoolchildren of 15-16 years, university students of 17-18 years). About 62% of all examined teenagers had the first degree of caries activity, 19.5% had the 2nd, and 18.5% had the 3rd degree of caries. Teenagers enrolled in college were divided according to the degree of caries activity: in the 1st degree – 36.3%, 2nd – 32.2%, 3rd – 31.5%, at school: 1st degree – 100%, at university: 1st degree – 97.4%, 2nd – 2.6%. At the age of 18, the number of college students who have a decompensated degree of caries activity increases to 36.6% due to a decrease in the number in the group with a subcompensated degree. University students in 100% of cases had a compensated degree of caries activity.
 Caries intensity rates in each age group are lower in schoolchildren than in college students and are the lowest in university students. In teenagers with the first degree of caries activity, the highest rate of caries intensity was observed in college (15-18 year adolescents), and the lowest – at school (15-16 years). University students, despite being 17-18 years old, had lower rates than college teens. All students had the first degree of caries activity. When comparing the rate of caries intensity in the studied 15 year-olds with the compensated degree of caries activity, it was found that in schoolchildren it is 1.7 times lower than in college students, in 16 year-olds – 1.5 times. At the age of 17 and 18 – 1.7 times, compared to university students.
 Thus, our research showed that college students of all studied age groups had worse indices than teenagers in the comparison groups. They have a more severe course of caries. The results suggest that further studies into the causes of caries in college students need to be conducted.

Selected salivary parameters in children with idiopathic nephrotic syndrome: a preliminary study

BackgroundDisturbances in the levels of serum constituents occurring in chronic renal diseases can be reflected in the saliva composition. The aim of this study was to assess some selected salivary components in children suffering from idiopathic steroid-sensitive nephrotic syndrome (iNS).MethodsA case–control study was performed on iNS and healthy participants. In unstimulated mixed saliva, pH, buffer capacity, total protein, α-amylase, peroxidase, calcium, magnesium, inorganic phosphate, fluoride, urea, uric acid and salivary flow rate were measured. Oral condition was assessed using dmft, DMFT, API and GI indices, usage of fluoride specimens and frequency of tooth brushing. Statistical analysis was performed by Shapiro–Wilk, Brown-Forsythe, Student’s t, ANOVA, Tukey’s and Pearson’s chi-square tests, Pearson’s and Spearman’s correlations, logistic regression and receiver operating characteristic (ROC) curve analysis.ResultsThe study involved 94 participants of both genders aged 4–17 (47 cases in relapse or remission phase of iNS and 47 controls) who were treated in the clinic of pediatric nephrology or outpatient dental clinic. Neither group differed in the number of caries-affected primary and permanent teeth, gingival condition or use of fluoride specimens. The iNS group presented lower levels of magnesium (0.41 ± 0.34 vs. 0.60 ± 0.38 mg/dL, P < 0.05) and fluoride (0.15 ± 0.10 vs. 0.21 ± 0.10 ppm, P < 0.01) and higher contents of urea (35.19 ± 15.55 vs. 25.21 ± 10.78 mg/dL, P < 0.01) and uric acid (2.90 ± 1.23 vs. 2.34 ± 1.04 mg/dL, P < 0.05) than the controls. In the iNS participants with relapse, a higher peroxidase activity and lower magnesium content than in the remission phase were found. ROC analysis showed a weak discriminatory power of these salivary constituents for the differentiation of participants with and without disease (accuracy from 66.0 to 67.0%, area under the ROC curve (AUC) from 0.638 to 0.682) and the relapse and remission phases (accuracy 70.2% and 68.1% and AUC 0.717 and 0.675, respectively).ConclusionsLevels of urea, uric acid, magnesium and fluoride in saliva can be associated with the course of iNS. Salivary levels of peroxidase and magnesium can be related to the phase of the disease. However, the measurements of these parameters cannot be useful as a noninvasive tool in diagnosing iNS and the phase of the disease.

ASSESSMENT OF CARIES IN DECIDUOUS TEETH IN CHILDREN WITH SOMATIC PATHOLOGY (LITERATURE REVIEW)

The purpose of the research is to analyze the data of scientific literature on the correlation of caries in deciduous teeth with various somatic diseases in children.&#x0D; Research materials and methods. The bibliosemantic method was used to analyze the results of previous research based on literature sources and electronic resources.&#x0D; Results of the research. Worldwide rates of general and dental morbidity, namely the incidence of caries, are constantly growing among the pediatric population, Ukraine being no exception. According to the results of research by leading domestic scientists, caries in children is 5 times more common than asthma, 4 times more common than obesity, and 20 times more common than diabetes. The caries of deciduous teeth deserves particular attention as its incidence increases with age. It is established that at the age of 1 caries is diagnosed in 12-15% of infants; after a year this figure doubles, in 3-year-olds it is diagnosed in every second child and increases to 85-95% in 6-7-year-old patients. The high incidence of dental caries is facilitated by the fact that caries is a multifactorial disease and one of the main causes of caries is the presence of somatic pathology in a child. According to the state statistics, the age dynamics in relation to disease accumulation index is as follows: among children 0-6 years, the index is 1,15; among children aged 7–14 - 1,46 and among adolescents - 1,7.&#x0D; Numerous scientific studies of domestic and foreign scientists reveal the relationship between the development of dental caries and somatic pathology. Since the body is a holistic system, this problem needs to be considered using a comprehensive approach of pediatricians and dentists.&#x0D; Kuzmina DA and co-authors identified four groups at risk of developing carious disease. The first group included children with diseases associated with impaired bone metabolism, the second – with dysbiotic disorders, the third – with trophic and the fourth group included children with chemical injuries of the oral cavity.&#x0D; At the same time, Murlanova TP found that the highest prevalence of caries of deciduous teeth is observed in children with diseases of the respiratory system (97.60%) and gastrointestinal tract (86.70%), the highest intensity (6.52 teeth) being observed in children with musculoskeletal system disorders.&#x0D; The dental status of children with type 1 diabetes was studied by Wang Y, Xing L, Yu H, Zhao L. The researchers analyzed 358 world publications and found that the prevalence of caries is on average 67%, with the highest rates (84%) in South America.&#x0D; Significantly more caries-affected teeth compared with somatically healthy children were found in the hepatobiliary system pathology. Systemic enamel hypoplasia is often diagnosed in children with hereditary and congenital diseases along with multiple caries lesions. The negative impact on children’s dental system has been established in adenoid hypertrophy. There have been conducted many studies on the dental status of children with disabilities associated with CNS diseases and different levels of anxiety, as well as children with mental retardation and severe speech disorders. The mass incidence of caries of deciduous teeth among 5-6 year old children according to WHO criteria was recorded in children with autism.&#x0D; The results of our research suggest a significantly higher incidence of caries of temporary teeth in children with pathology of the musculoskeletal system (MSS) than in somatically healthy children. The analysis of dental caries considering the nature of MSS disorders showed more caries-affected teeth in children with combined pathology than in children with flat feet and posture disorders.&#x0D; The results of the study confirm the correlation between dental caries and somatic pathology and will be aimed at addressing the development of a differentiated program for the prevention of dental caries in children with somatic status in the future.

Oral health conditions in children with idiopathic nephrotic syndrome: a cross-sectional study

BackgroundNephrotic syndrome is one of the chronic illnesses in the pediatric age group. The aim of this study was to assess the oral health of patients with steroid-sensitive idiopathic nephrotic syndrome (iNS).MethodsA case-control study was performed on iNS patients and healthy from May 2018 to April 2019. Dental caries was assessed by the World Health Organization criteria, developmental defects of enamel by the mDDE index, oral hygiene by the OHI-S and API, and gingival condition by the GI. Oral health behavior was recorded using a standardized questionnaire including tooth brushing, fluoride prevention, dietary habits and utilization of dental care. Additionally, Streptococcus mutans (SM) and Lactobacillus spp. (LB) bacteria in saliva were assessed using the CRT bacteria test. Statistical analysis comparing oral health parameters was carried by Pearson’s chi-squared, Fisher’s exact, Shapiro-Wilk verified by Student’s t or Mann-Whitney U tests.ResultsThe study included 94 participants of both sexes at the age of 4 to 17 years (47 cases and 47 controls) who were treated in Clinic of Pediatric Nephrology or outpatients’ dental clinic in Wroclaw, Poland. The iNS patients compared to the controls revealed some lower caries experience (83.0% vs 95.7%) and number of caries affected primary and/or permanent teeth (4.6 ± 3.5 vs 6.0 ± 4.1), a significantly lower number of filled primary and/or permanent teeth (1.1 ± 1.6 vs 3.5 ± 3.0, P < 0.001) and higher incidence of enamel hypoplasia (31.9% vs 4.3%, P < 0.001). The numbers of the iNS patients with high level of SM and LB were similar to the controls. The iNS patients had a higher OHI-S score (1.89 ± 1.59 vs 1.05 ± 1.02, P < 0.010) and a higher GI score (0.7 ± 1.0 vs 0.3 ± 0.6, P = 0.050). Moreover, they less frequently brushed their teeth twice a day (78.8% vs 93.6%, P = 0.026) and more frequently consumed three or more snacks daily (53.2% vs 23.4%, P = 0.002).ConclusionsThe iNS patients despite the poor oral hygiene revealed lower caries experience but smaller number of restored caries-affected teeth, more severe gingivitis and more frequently teeth affected by enamel hypoplasia.

Dentists clinical decision-making for erosive tooth wear: An online pilot study

ObjectiveErosive tooth wear (ETW) is an irreversible loss of dental hard tissue. This pilot study examined dentists’ ability to diagnose and manage ETW relative to sound and caries-affected teeth. MethodsDentists recruited through the Indiana Dental Association (N = 36) participated in an internet-based survey, containing twenty-two standardized images of buccal and occlusal surfaces of teeth (sound, ETW, or caries). For each image, they provided diagnosis (presence and differentiation) of dental condition, confidence in their judgment, management need, and likelihood to recommend specific management strategies. Dentists made these judgments for teeth with no, initial, moderate, or severe ETW/caries. ResultsDentists demonstrated poor detection of ETW compared to sound teeth and caries at each level of severity. The dentists were less confident, less able to correctly diagnose and manage ETW, and less likely to recommend most management strategies for ETW than caries at each level of severity. ConclusionsDentists had difficulty correctly diagnosing (both detection and differentiation) and managing ETW, across all severity levels and particularly in early stages. These difficulties were particularly apparent when compared to caries. The current results are clinically relevant given the importance of early diagnosis for ETW management.

Prevalence of traumatic dental injuries in Polish 15-year-olds.

Traumatic dental injuries (TDIs) can occur at any age. They may cause health, functional, esthetic, and psychological problems, negatively affecting quality of life. The objective of this study was to assess the prevalence, causes, treatment, and risk factors of TDIs among Polish adolescents. As part of a cross-sectional national monitoring survey concerning the oral health condition and its determinants in the Polish population, 992 15-year-olds of both sexes were examined. The subjects were the residents of the urban and rural areas of 10 from a total of 16 provinces of the country. Caries-affected teeth were assessed according to the World Health Organization (WHO) criteria, and caries prevalence and the decayed, missing or filled teeth (DMFT) index values were calculated. Traumatic dental injuries were assessed with the use of the WHO criteria, modified for retrospective evaluation. The details of clinically diagnosed TDI were supplemented by a questionnaire and an interview. Overall, TDIs occurred in 22.0% of the subjects, similarly often in urban and rural areas (23.0% and 20.9%, respectively; p = 0.439), and more frequently in males than in females (26.2% and 18.2%, respectively; p = 0.002). The most common damage was crown fracture (46.2%), followed by luxation (43.9%) and avulsion (9.9%). Among the traumatized teeth, 73.8% received crown fracture restorations, 29.6% root canal treatment, and 17.5% were splinted due to luxation or avulsion. The most common cause of TDIs were accidental falls - 96.3%, including playing sports (27.1%), the other referred to violence/fight (3.7%). Nearly 14% of the accidents took place at school. The likelihood of TDI experience in males was 1.59-fold higher than in females. Males revealed a 2.76-fold higher probability of TDI incidence during participation in sports activities. Other predictors of TDIs were a low level of education of the mother, a poor socioeconomic status and a high DMFT score. A relatively high prevalence of TDIs in Polish 15-year-olds calls for effective planning and intervention to prevent the occurrence of the injuries and their aftereffects.

Are dental patients able to perceive erosive tooth wear on anterior teeth?: An internet-based survey assessing awareness and related action

BackgroundErosive tooth wear (ETW) is irreversible loss of dental hard tissue. The authors examined patients’ ability to recognize ETW relative to sound teeth and teeth with caries. MethodsUsing Amazon’s crowdsourcing service, the authors recruited participants (N = 623) to view standardized images of buccal surfaces of teeth (sound, ETW, or caries). Participants reported whether a dental condition existed (yes or no), likelihood to seek care, and esthetic attractiveness for teeth with no, initial, moderate, or severe signs of ETW or caries. ResultsDental patients showed poor recognition of cases of ETW, especially compared with sound and caries-affected teeth at each level of severity. Patients were less likely to schedule a dental appointment for care or treatment of teeth with ETW than for teeth with caries at each level of severity. Patients also found ETW more esthetically attractive than caries at each level of severity and found initial ETW more attractive than sound teeth. ConclusionsDental patients struggle to recognize ETW, in general and compared with caries, at each level of severity and particularly for early stages of ETW. These recognition difficulties likely arise, in part, from tooth esthetic attractiveness standards (smooth and shiny teeth look more esthetic), possibly leading to lack of appropriate care-seeking behavior. Practical ImplicationsThis internet-based tool may be used to assess dental patients’ awareness and ability to recognize cases of ETW. Improved patient awareness might lead to seeking professional care to prevent or delay ETW progression.

Age estimation based on aspartic acid racemization in dentine: what about caries-affected teeth?

Age estimation based on aspartic acid racemization (AAR) in dentine is one of the most precise methods in adult age. Caries induces protein degradation and may have an impact on the kinetics of AAR in dentine. We systematically examined standardized prepared dentine samples from caries-affected teeth to clarify the question, if caries-affected teeth should not be used for age estimation based on AAR at all, or if the analysis of dentine samples from such teeth may be useful after removal of the caries-affected tissue according to clinical standards. Our results suggest that caries may lead to an extensive protein degradation even in macroscopically healthy-appearing dentine samples from caries-affected teeth and may significantly affect the precision of age estimation. To ensure the quality of age estimation based on AAR in forensic practice, we recommend using dentine samples from healthy teeth. If only caries-affected teeth are available, dentine samples from at least two teeth from the same individual should be analyzed as it seems unlikely that caries-induced protein degradation occurred with identical kinetics in two different teeth. In any case, results of the analysis of caries-affected teeth must be interpreted with caution.

Effect of 2% chlorhexidine gluconate cavity disinfectant on microtensile bond strength of tooth-coloured restorative materials to sound and caries-affected dentin

This study evaluated the effect of 2% chlorhexidine gluconate-based cavity disinfectant (CHX) on the microtensile bond strength (μTBS) of glass ionomer, resin-modified glass ionomer and packable resin composite to sound and caries-affected dentin. Sound and occlusal caries-affected human third molars (N = 36, n = 3 per group) were randomly divided into three experimental groups to receive one of the following restorative materials. (a) Glass ionomer (Ketac Molar, 3 M ESPE; GI), (b) resin-modified glass ionomer (Vitremer, 3 M ESPE; RMGI) and (c) packable resin composite (Surefil, Dentsply; PRC) with a bonding agent (Prime Bond NT, Dentsply De Trey). Caries was removed using a caries-detecting dye (Caries Detector, Kuraray Medical Ltd.) and flat dentin surfaces were achieved by finishing up to 1200-grit silicon carbide abrasive. Half of the teeth in each group received 2% CHX (Consepsis, Ultradent). Dentin surfaces were built-up with the respective materials incrementally and were sectioned with a slow-speed saw into multiple beams. The beams were subjected to μTBS test (0.5 mm/min) in a Universal Testing Machine. The data were analysed using two-way analysis of variance and Tukey’s tests. For each restorative material, μTBS results were not affected by the application of CHX (p > 0.05) on both sound and caries-affected dentin (p > 0.05). PRC in combination with the corresponding bonding agent showed significantly higher results (p < 0.05) than those of GI and RMGI, on sound and caries-affected teeth, respectively. Cohesive failure in dentin was not observed in any of the groups. The use of 2% chlorhexidine-based cavity disinfectant did not impair the adhesion of the restorative materials tested to either sound or caries-affected dentin.

The Simultaneous Effect of Extended Etching Time and Casein Phosphopeptide-Amorphous Calcium Phosphate containing Paste Application on Shear Bond Strength of Etch-and-rinse Adhesive to Caries-affected Dentin.

This study evaluated the simultaneous effect of extended etching time and casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) containing paste application on shear bond strength (SBS) of etch-and-rinse adhesive to caries-affected-dentin (CAD). Fifty human third molars were used; 10 normal in group 1 and 40 caries-affected teeth in groups 2 to 5. In the CAD groups, teeth were randomly assigned into four groups (n = 10). In groups 2 and 4, phosphoric acid etching for 15 and 45 seconds was used and in groups 3 and 5, after 15 or 45 seconds etching respectively, CPP-ACP containing paste (MI paste) was applied for 3 minutes. After rinsing, single bond adhesive system and Z250 composite were used for resin composite build-up in all groups. After storage, SBS test was measured at cross head speed of 0.5 mm/min. Data were analyzed using one/two-way ANOVA and Tukey HSD test (α = 0.05). Normal dentin groups showed the highest SBS among different groups. There was a statistically significant difference between different etching times in CAD groups (p < 0.05), but there were no significant differences between SBS of SB adhesive to CAD with or without CPP-ACP pretreated in both etching times. Most of the failure modes were adhesive except in groups 1 and 5 which cohesive failure in composite was also observed. The results of our study indicated that extended etching time up to 45 seconds could enhance the SBS of CAD and approach nearly to SBS of normal dentin. Moreover, MI paste pretreatment had not significant effect on SBS of etch-and-rinse adhesive in CAD. Simultaneous application of extended etching time and CPP-ACP containing paste may be a suggested method in increasing the SBS of adhesive to CAD.

Abundance of MMPs and Cysteine Cathepsins in Caries-affected Dentin

Degradation of dentin matrix components within caries dentin has been correlated with the activity of host-derived proteases, such as matrix metalloproteases (MMPs) and cysteine cathepsins (CTs). Since this relationship has not been fully established, we hypothesized that the abundance of MMPs and CTs in caries-affected dentin must be higher than in intact dentin. To test this premise, we obtained 5 slices (200 µm) from 5 intact teeth and from 5 caries-affected teeth (1 slice/tooth) and individually incubated them with primary antibodies for CT-B, CT-K, MMP-2, or MMP-9. Negative controls were incubated with pre-immune serum. Specimens were washed and re-incubated with the respective fluorescent secondary antibody. Collagen identification, attained by the autofluorescence capture technique, and protease localization were evaluated by multi-photon confocal microscopy. The images were analyzed with ZEN software, which also quantitatively measured the percentages of collagen and protease distribution in dentin compartments. The abundance of the test enzymes was markedly higher in caries-affected than in intact dentin. CT-B exhibited the highest percentage of co-localization with collagen, followed by MMP-9, MMP-2, and CT-K. The high expression of CTs and MMPs in caries-affected teeth indicates that those host-derived enzymes are intensely involved with caries progression.

Effect of two different chemomechanical caries removal agents on dentin microhardness: An in vitro study

Aim:The aim of this in vitro study was to evaluate the effect of two different chemomechanical caries removal (CMCR) agents on dentin microhardness.Materials and Methods:In this study, the crown portion of ten carious-free and ten caries-affected teeth were selected. In carious-free samples, the teeth were decoronated at the level of cemento – enamel junction. Only the crown portion of the teeth was selected. Occlusal one-third of the crowns were cross-sectioned and discarded to expose the dentin, and it was divided into two groups, five teeth in each group. Then, they were further sectioned longitudinally through the centre. In one group, no agent was applied on one half and Carisolv was applied on other half. In another group, no agent was applied on one-half and Carie-Care was applied on the other half for 1 min. In carious samples, the crowns were sectioned through the centre of carious lesion. Carisolv was applied on one-half and Carie-Care was applied on the other half. After using CMCR agents, surface hardness of dentin was examined using Vickers hardness number (VHN).Statistical Analysis and Results:The data were analyzed using t-test and one-way analysis of variance (ANOVA). There were no significant difference among normal dentin (62.91 ± 2.76), Carisolv-treated normal dentin (61.72 ± 2.89), and Carie-Care-treated normal dentin (61.90 ± 3.19). In carious samples, the results of Carisolv-treated dentin (58.57 ± 2.62) was not statistically significantly different from those of the Carie-Care-treated dentin (56.77 ± 4.41).Conclusion:In conclusion, neither of the CMCR methods caused a significant change in the microhardness of normal dentin and the treated carious dentin.

Effect of nicotine on growth and metabolism of Streptococcus mutans

Streptococcus mutans is a key contributor to dental caries. Smokers have a higher number of caries-affected teeth than do nonsmokers, but the association among tobacco, nicotine, caries, and S. mutans growth has not been investigated in detail. Seven S. mutans strains--UA159, UA130, 10449, A32-2, NG8, LM7, and OMZ175--were used in the present study. The minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), minimum biofilm inhibitory concentration (MBIC), planktonic cell growth, biofilm formation, metabolism, and structure (determined using scanning electron microscopy) of the seven strains treated with different concentrations of nicotine (0-32 mg ml(-1)) were investigated. The MIC, MBC, and MBIC were 16 mg ml(-1) (0.1 M), 32 mg ml(-1) (0.2 M), and 16 mg ml(-1) (0.1 M), respectively, for most of the S. mutans strains. Growth of planktonic S. mutans cells was significantly repressed by 2.0-8.0 mg ml(-1) of nicotine. Biofilm formation and metabolic activity of S. mutans was increased in a nicotine-dependent manner up to 16.0 mg ml(-1) of nicotine. Scanning electron microscopy revealed that S. mutans treated with a high concentration of nicotine a had thicker biofilm and more spherical bacterial cells. In summary, nicotine enhances S. mutans biofilm formation and biofilm metabolic activity. These results suggest that smoking can increase the development of caries by fostering increased formation of S. mutans biofilm on tooth surfaces.

An Analysis of Etiological Factors for Traumatic Mandibular Osteomyelitis

The aim of this study was to analyze the factors that were associated with the development of osteomyelitis during the treatment of mandibular fractures. The data of 3188 patients with mandibular fractures treated during 2002-2009 were analyzed. Traumatic osteomyelitis of the mandible was diagnosed in 207 patients. The background factors of complications were studied and compared with the control group (100 patients) not having complications after treatment of mandibular fractures. The data of clinical, roentgenologic, microbiological, and immunological investigations were analyzed. A logistic regression model was developed to identify the factors for osteomyelitis development. The treatment in 6.5% of patients was complicated with osteomyelitis; 88.5% of these patients were men, and more than 80% of patients were younger than 50 years. In 86.8% of cases, Staphylococcus species were isolated, with Staphylococcus aureus accounting for 69.1% of cases. The following factors were found to be associated with osteomyelitis development: immunity dysfunction, caries-affected teeth at the fracture line, mobile fractured bones, bone fixation after more than 7 days following trauma, healthy teeth at the fracture line, insufficient bone reposition, and bone fixation after 3-7 days following trauma. Comparative analysis of factors influencing the treatment results revealed a great importance of immunological and dental status and microflora at the affected site. Insufficient or late reposition and fixation of fractured bone fragments play a significant role in the healing process.

Nanoleakage related to bond strength in RM-GIC and adhesive restorations

This was to investigate the nanoleakage of Resin Modified Glass Ionomer Cement (RMGIC) and composite resin (CR) restorations in sound and caries-affected primary dentine, submitted to load cycling and cariogenic challenge in vitro. Occlusal cavities were prepared in 60 sound exfoliated primary second molars and 30 specimens were subjected to chemical induction of artificial caries lesions and the others were restored without caries induction. All prepared teeth were divided into 2 groups according to restorative materials. From each dentine condition 5 restored teeth and restorative material were subjected to microtensile bond strength and nanoleakage tests immediately or after load-cycling or submitted to the pH-cycling procedure before testing. The adhesive presented bigger areas of silver leakage at the interfaces on caries-affected dentine (2.46±0.47)mm2 than sound dentine (0.90±0.19)mm2. RMGIC nanoleakage was not influenced by the sound (1.75±0.11)mm2 or caries-affected (2.08±0.39) condition of the substrate. A significant moderate inverse correlation was revealed between the bond strength and silver leakage area at the interface, (r= -0.55, p<0.001). Nanoleakage is greater in caries-affected primary teeth dentine than sound dentine in adhesive restorations although at the interfaces of RMGIC does not differ. As nanoleakage increases, bond strength decreases significantly.

Ozone therapy in dentistry: A literature review

This review of literature is an attempt to summarize different modalities of ozone application in dentistry. Ozone gas has a high oxidation potential and is effective against bacteria, viruses, fungi, and protozoa. It also has the capacity to stimulate blood circulation, platelets, and immune response. Ozone is used in dentistry in gaseous, ozonated water and as ozonated oils. Ozone was shown to be biocompatible and is used in all aspects of dentistry. It has been shown to stimulate remineralization of recent caries-affected teeth and is used as a preventive therapy in caries, root caries, and intracanal irrigants in endodontic treatment. It has been used in treatment of alveolitis, avascular osteonecrosis of the jaw, and herpes virus infection. It also inhibits plaque formation and can be used as an adjuvant in periodontal surgical and maintenance phase. Ozone has also been used in dental unit water line to disinfect water. Advantage of ozone therapy is it is an atraumatic, biologically based treatment. While laboratory studies suggest a promising potential of ozone in dentistry, less number of clinical studies were documented. More number of randomized, controlled trials need to be conducted to determine the precise indications and guidelines to treat various dental pathologies with this promising medical agent.

Effect of carisolv and papacárie on the resin-dentin bond strength in sound and caries-affected primary molars

Aim: This study evaluated the influence of different chemomechanical caries removal techniques on the bond strength of an adhesive system to caries-affected and healthy dentin. Methods: Thirty healthy teeth were randomly divided into three groups: Group 1 (control): no caries removal technique was applied; Group 2: chemomechanical technique using Carisolv ® ; and Group 3: chemomechanical technique using Papacarie ® . Twenty caries-affected teeth were divided into two groups: Group 4: chemomechanical technique using Carisolv; and Group 5: chemomechanical technique using Papacarie. The teeth received the application of an etch-andrinse adhesive system, were restored with composite resin, and then sectioned to obtain 4 hourglassshaped slabs from each specimen, which were subjected to a microtensile bond strength test. Data were analyzed statistically by ANOVA and Tukey’s test (a=0.05). Results: G1 (13.387 ± 6.1074), G2 (18.123 ± 3.2611) and G3 (12.781 ± 4.5652) presented statistically significant higher mean bond strength values than the other groups (p 0.05). G4 (6.228 ± 5.3435) and G5 (6.482 ± 3.2076) presented the lowest mean bond strength values and were statistically similar to each other (p>0.05). Conclusions: Neither of the chemomechanical caries removal methods interfered in the resin-dentin bond strength. However, lower tensile bond strength was found to caries-affected dentin.