Association study for the role of Matrix metalloproteinases 2 and 3 gene polymorphisms in dental caries susceptibility

ObjectiveVarious exogenous and endogenous risk factors have been described as contributing to dental caries susceptibility. In the last decade it has been established that both pro and active forms of host derived Matrix metalloproteinases (MMPs) are present in the oral cavity. MMPs role in caries development has been hypothesized. The aim of this study was to analyse MMP2 (rs2287074) and MMP3 (rs679620) single nucleotide polymorphisms (SNPs) and their role in caries susceptibility.DesignThe two SNPs were analysed by PCR- restriction fragment length polymorphism (RFLP) in a sample of 102 ethnic Bulgarian volunteers (42 males and 60 females), all students in Sofia Medical University.ResultsStatistical analysis of the MMP2 SNP showed significant differences for the genotype frequencies between the caries free (CF, DMFT = 0) and low caries experience (LCE, DMFT ≤ 5) groups. Analysis for the non-synonymous MMP3 SNP found significant differences between both CF vs caries experience groups (LCE+ high caries experience (HCE, DMFT ≥ 5)) and LCE vs HCE groups. The presence of allele G decreased the risk of HCE about 4 times.ConclusionsMMP2 and MMP3 genes are likely to be involved in caries susceptibility in our population. However, as dental caries is a multifactorial disorder and several genes are likely to have influence on it, it is reasonable to expect that SNPs, even those proven to be functional like rs679620, potentially play a significant, but not major role in the disease outcome.     

The association of Enamelin,Lactoferrin, and Tumour necrosis factor alpha gene polymorphisms with high caries susceptibility in Chinese children under 4 years old

ObjectiveThe aim of this study was to assess the role of ENAM rs3796703, LTF rs1126478, and TNF-α rs1800629 in high caries susceptibility.DesignThe present case–control study included 1005 unrelated children under 4 years old: 505 with severe caries (dmft index ≥4) and 500 who were caries-free (dmft index = 0 and without white-spot lesions). Questionnaires were obtained from parents and gardians about the children’s diet and oral behavioural habits. All the children received dental examinations and oral swabbing for human genomic DNA collection. ENAM rs3796703, LTF rs1126478, and TNF-α rs1800629 were genotyped by Sanger sequencing.ResultsThe frequency of the ENAM rs3796703 T allele (6.7% in the caries group and 4.2% in the caries-free group), CT genotype (12.7% in the caries group and 8.4% in the caries-free group), TNF-α rs1800629 A allele (4.8% in the caries group and 6.8% in the caries-free group), and AG genotype (8.7% in the caries group and 13.2% in the caries-free group) were significantly different between the caries and caries-free groups (p < 0.05). No significant difference was found in the LTF rs1126478 allele frequency and genotype distribution between the two groups. The ENAM rs3796703 CT genotype increased caries susceptibility by 60.9% compared to the CC genotype (β = 0.746, OR = 1.609), and the TNF-α rs1800629 AG genotype reduced caries susceptibility by 47.4% compared to the GG genotype (β = −0.642, OR = 0.526). In terms of habits covariates, prolongation of night feeding time by 1 month increased caries susceptibility by 3.3% (β = 0.033, OR = 1.033); additionally, sweets and acidic drinks consumption 1–2 times per day increased caries susceptibility by 218.2% (β = 1.158, OR = 3.182), and consumption 3 or more times pe/r day increased susceptibility by 883.5% (β = 2.286, OR = 9.835) compared to non-consumption. Topical fluoride application decreased caries susceptibility by 43.0% (β = −0.562, OR = 0.570).ConclusionsThe ENAM and TNF-α genes are likely associated with caries experience in Chinese children. The ENAM rs3796703 CT genotype might be involved in caries susceptibility, while TNF-α rs1800629 AG genotype might be involved in caries protection.     

Randomized clinical trial on effectiveness of silver diamine fluoride and glass ionomer in arresting dentine caries in preschool children

ObjectiveTo compare the effectiveness of annual topical application of silver diamine fluoride (SDF) solution, semi-annual topical application of SDF solution, and annual application of a flowable high fluoride-releasing glass ionomer in arresting active dentine caries in primary teeth.MethodsA total of 212 children, aged 3–4 years, were randomly allocated to one of three groups for treatment of carious dentine cavities in their primary teeth: Gp1-annual application of SDF, Gp2-semi-annual application of SDF, and Gp3-annual application of glass ionomer. Follow-up examinations were carried out every six months to assess whether the treated caries lesions had become arrested.ResultsAfter 24 months, 181 (85%) children remained in the study. The caries arrest rates were 79%, 91% and 82% for Gp1, Gp2 and Gp3, respectively (p = 0.007). In the logistic regression model using GEE to adjust for clustering effect, higher caries arrest rates were found in lesions treated in Gp2 (OR = 2.98, p = 0.007), those in anterior teeth (OR = 5.55, p < 0.001), and those in buccal/lingual smooth surfaces (OR = 15.6, p = 0.004).ConclusionAnnual application of either SDF solution or high fluoride-releasing glass ionomer can arrest active dentine caries. Increasing the frequency of application to every 6 months can increase the caries arrest rate of SDF application.Clinical significanceArrest of active dentine caries in primary teeth by topical application of SDF solution can be enhanced by increasing the frequency of application from annually to every 6 months, whereas annual paint-on of a flowable glass ionomer can also arrest active dentine caries and may provide a more aesthetic outcome.     

The effect of dietary intervention on paraffin-stimulated saliva and dental health of children participating in a randomized controlled trial

ObjectivesThe aim was to study the impact of dietary intervention on the properties of paraffin-stimulated saliva, and on dental caries.Study designAt 7 months of age 1062 infants (540 intervention; 522 controls) started in the prospective, randomized Special Turku Intervention Project (STRIP) aimed at restricting the child's saturated fat and cholesterol intake to prevent atherosclerosis of adult age (www.clinicaltrials.gov NCT 00223600). At 3 years of age, every fifth child was invited to an oral sub-study, and 148 (78 boys) children attended. At 6, 9, 12 and 16 years of age 135, 127, 114 and 88 children were restudied, respectively. Dietary intakes of carbohydrates, protein, saturated fat, calcium, phosphate, and fibre were regularly recorded using 4-day food records. Height and weight were regularly monitored. Paraffin-stimulated saliva samples were collected at 6, 9, 12 and 16 years of age, and analyzed for flow rate, buffer capacity, calcium, phosphate and proteins. Dental health was recorded and expressed as d₃mft/D₃MFT, and as time of caries onset.ResultsDietary intakes of calcium, phosphate and fibre, and salivary flow rate increased with time in both groups (p < 0.001, GLM for repeated measures). Fibre intake and salivary flow rate were higher in the intervention than in the control group (p = 0.042 and p = 0.0394, respectively, GLM for repeated measures). There were no correlations between dietary intakes and salivary concentrations of calcium or phosphate. Children who did not have caries experience (d₃mft/D₃MFT = 0) during the entire follow-up had higher salivary calcium than those who had caries already at 3 years of age. The association between salivary calcium and caries onset was significant up to 12 years of age. Toothbrushing frequency was statistically significantly associated with caries-onset at ages 6 (gamma statistic 0.457, p = 0.046) and 12 years (gamma statistic 0.473, p = 0.019).ConclusionsThe current long-term dietary intervention increased children's paraffin-stimulated salivary flow rate. The concentration of salivary calcium was directly correlated to dental health. Higher salivary flow rate in the intervention group is believed to be due to higher fibre intake in the intervention group.     

Risk behaviors and its association with caries activity and dental caries in Japanese children

The aim of this study was to assess risk behaviors and its association with caries activity and dental caries in Japanese children. The subjects were 392 young Japanese children who underwent dental health check-up at 18, 30 and 42 months of age. Oral examinations, Cariostat tests and dental health questionnaires were carried out at each time. The caries prevalence of children was 1.5% at 18 months, 9.9% at 30 months and 28.1% at 42 months. Caries activity based on the Cariostat scores of children was correlated with caries status (caries-free/carious) at 42 months. In children with caries during each examination period at 42 months, eating snacks while playing was ranked as the most important behavioral risk (P < 0.001), followed by breast-feeding (P < 0.01), non setting of time for snacks (P < 0.05) and frequency of snacks (P < 0.05) at 18 months old; non brushing by mother (P < 0.05) and eating snacks while playing (P < 0.05) were ranked highest at 30 months old. In addition, eating snacks while playing (P < 0.001) at 42 months old was the only a significant factor for children with caries. Caries activity and risk behaviors were associated with caries experience at different age periods of childhood.     

Effectiveness of three age estimation methods based on dental and skeletal development in a sample of young Brazilians

ObjectiveThis study compared three methods designed for age estimation.MethodsA sample of 468 radiographs (234 panoramic and 234 carpal radiographs) collected from patients ranging from 5 to 14 years old (mean age: 11.27 years old ± 2.27 years) was used. Three age estimation methods: were applied: one founded on dental development, one founded on hand and wrist development, and a method combining both measurements. For each method, the mean error (ME), mean absolute error (MAE), root mean square error (RMSE), and mean percentage of absolute error (MPAE) were quantified. The methods: were compared based on their effectiveness for estimating age in relation to sex and age range.ResultsThe data show that the method exclusively using the development of the hand and wrist had the highest error rates (ME: 1.28 M, 1.85F; MAE: 1.64 M, 1.96F; RMSE: 1.94 M, 2.32F) for both males (M) and females (F). In males, the method combining dental and skeletal development obtained outcomes that were slightly better than the method founded on only dental development (MPAE: 6.99% and 7.47%, respectively). In females, the opposite result was observed (MPAE: 8.48% and 6.59%, respectively). The method founded exclusively on skeletal development significantly overestimated (p = 0.001) the age (mean chronological and estimated ages: 11.27 and 12.88, respectively).ConclusionThe methods involving dental development provided more accurate age estimates of chronological age. The method exclusively based on hand and wrist development resulted in outcomes that were highly discrepant from the chronological age.     

A radiographic study of third molar crown development in a group of Nigerian children

The present study assessed developmental stages of third molar crowns in a group of Nigerian children and compared development across arches in relation to chronological age and sex.MethodologyPanoramic radiographs of 560 healthy Nigerian children aged 5 to 15 years were reviewed. The stages of development of third molar crowns across arches were assessed and determined using the criteria defined in Gravely's classification of crown formation. A score was recorded in each quadrant for each child. Data was analyzed using Epi-info 6 version for windows. Statistical significance was inferred at P < 0.05.ResultsMales 267 (47.7%), females 293 (52.3%). Mean age 10.4 years (SD52.5). Earliest evidence of crypt formation was observed at age 5.0. Mean age for stage 1 of crown calcification was 7.55, 7.75, 8.24 and 8.88 for the lower right, lower left, upper right and upper left quadrant of the jaws respectively. Differences observed between males and females were significant for stage 1 upper right molar crown development, (P = 0.03). In children 12 years and above, approximately 75% of the crowns visible on radiographs were at least half formed. Mean age for stage 5 of crown formation and initiation of root formation was between 13.10 and 13.43 years. The proportion of agenesis among children aged 12 years and above was 0.7.ConclusionsThe first sign of third molar crown development was observed as early as age 5. A positive correlation was observed between third molar development and chronological age. Proportion of agenesis in children aged 12 years and above was 0.7.     

Meta-analysis of teeth from European populations before and after the 18th century reveals a shift towards increased prevalence of caries and tooth loss

Based on single studies, it has been hypothesised that Europeans have suffered less frequently from caries before the 18th century than after the 18th century and that females have higher caries prevalence, but systematic European-wide overviews are sparse.We collected published data on dental diseases (publication between 1981 and 2015 with reports on 29 cohorts with 4998 individuals and a total of 85817 teeth).Meta-analyses revealed that, over several hundred years, including the post-18th century era, Europeans had relatively constant frequencies of caries and ante-mortem tooth loss, but since the 18th century, the mean frequencies of these dental diseases increased (each p < 0.05). Tooth loss correlated with caries and odontogenic abscesses (each p < 0.05). Although the mean caries and ante-mortem tooth loss frequencies increased since the 18th century, there are overlaps with many pre-18th century cohorts. In addition, in contrast to previous hypotheses, no general increase of caries prevalence in females could in fact be verified.It is likely that changes in nutrition (more sugar) and dental health (possibly higher frequency of tooth extraction) could be the underlying factors which led to this minor to moderate shift of dental disease frequencies in Europe.     

Promotion of enamel caries remineralization by an amelogenin-derived peptide in a rat model

ObjectiveAn amelogenin-derived peptide has been shown to promote remineralization of demineralized enamel in an in vitro model of initial caries induced by pH cycling. The present study examines whether the peptide exerts similar effects within the complex oral environment in vivo.DesignSpecific pathogen-free Sprague-Dawley rats (n = 36) were infected with Streptococcus mutans, given ad libitum access to Diet 2000 and drinking water supplemented with sucrose (10%, w/v), and then randomly divided into three groups treated with 25 μM peptide solution, 1 g/L NaF or deionized water. Molar teeth were swabbed twice daily with the respective solutions for 24 days. Then animals were killed, their jaws were removed and caries lesions were analyzed using the quantitative light-induced fluorescence-digital (QLF-D) technique to measure changes in mineral content. To verify QLF-D results, caries were scored for lesion depth and size using the Keyes method, and analyzed using polarized light microscopy (PLM).ResultsMineral gain was significantly higher in teeth treated with peptide or NaF than in teeth treated with water (p < 0.05), based on the QLF-D results (ΔF and ΔQ). Incidence of smooth-surface and sulcal caries based on Keyes scores was similar in rats treated with peptide or NaF, and significantly lower in these groups than in rats treated with water (p < 0.05). Lesions on teeth treated with peptide or NaF were shallower, based on PLM. No significant differences were observed between molar enamel caries treated with peptide or NaF.ConclusionsThis amelogenin-derived peptide can promote remineralization in a rat caries model, indicating strong potential for clinical use.     

Frequency of periodontal pathogens in equivalent peri-implant and periodontal clinical statuses

ObjectivesThis study tested the hypotheses that there is: (1) higher bacterial frequency in peri-implantitis/periodontitis, followed by mucositis/gingivitis and peri-implant/periodontal health; (2) similar bacterial frequency between comparable peri-implant and periodontal clinical statuses.Design of studyThe presence of Porphyromonas gingivalis, Tannerella forsythia, Campylobacter rectus, Prevotella intermedia, Treponema denticola and Aggregatibacter actinomycetemcomitans was evaluated in peri-implant (n = 53) and periodontal (n = 53) health; mucositis (n = 50), gingivitis (n = 50), peri-implantitis (n = 50) and periodontitis (n = 50).ResultsThe pattern of peri-implant bacterial frequency was not as expected (peri-implantitis > mucositis > health). Except for P. intermedia (p > 0.05), bacterial frequency was higher in peri-implantitis than health (p < 0.05). The frequency of P.gingivalis and red complex species were higher in peri-implantitis than mucositis (p < 0.05). In periodontal samples, T. forsythia and T. denticola showed the expected pattern of frequency (periodontitis > gingivitis > health). The frequencies of C. rectus and T. forsythia were higher in healthy teeth/gingivitis than healthy implants/mucositis, respectively (p < 0.05). The frequency of P. gingivalis and A. actinomycetemcomitans were similar between periodontitis and peri-implantitis (p > 0.05) while all other species occurrences were higher in periodontitis than peri-implantitis (p < 0.05).ConclusionsBacterial frequency increased from peri-implant/periodontal health to peri-implantitis/periodontitis but not from mucositis/gingivitis to peri-implantitis/periodontitis. There was a trend towards higher bacterial frequency in teeth than implants.     

Influence of loading frequency on implant failure under cyclic fatigue conditions

ObjectivesPreliminary studies on implant fatigue testing suggested that fractures were more likely to occur at 2 Hz than at 30 Hz (χ², p < 0.05). This investigation explores frequency and base elastic modulus effects on strain, strain rate and failure.MethodsA total of 66 implants were mounted in different base materials (acrylic, glass-filled epoxy, aluminum) and loaded up to 10⁶ cycles per ISO 14801 (20 N to 420–500 N) at frequencies of 2 Hz and 30 Hz (chosen to accelerate frequency as the stressor). Absolute strain magnitudes and strain rates under varying loading conditions and with different base materials were measured using one strain-gauged implant. Failure probability distributions were analyzed by both Weibull and life data analysis. Measured strain was used to validate an FEA model. Fracture surfaces were examined by SEM.ResultsNumber of failures and failure-rates-per-cycle differed significantly between implants tested at 2 Hz versus 30 Hz (p < 0.05). Strain magnitude was independent of frequency. Strain rates were highly correlated with frequency (linear r² > 0.99) and differed significantly under failure conditions (420 N): 2 Hz = 8292 μstrain/s; (500 N): 30 Hz = 80,840 μstrain/s. Measured and FEA-calculated strains were similar. Fracture surfaces were indistinguishable (2 Hz versus 30 Hz).SignificanceFatigue failure was significantly more likely at 2 Hz than 30 Hz whereas base material and loading magnitude seemed to have only minor influence. Absolute strain was identical at these frequencies suggesting strain rate sensitivity for this commercially pure titanium implant. Both the Weibull and SEM analyses support an identical failure mechanism with damage accumulation more severe at lower frequencies, an interpretation consistent with strain rate sensitivity.     

Nano-calcium phosphate and dimethylaminohexadecyl methacrylate adhesive for dentin remineralization in a biofilm-challenged environment

ObjectiveDentin remineralization at the bonded interface would protect it from external risk factors, therefore, would enhance the longevity of restoration and combat secondary caries. Dental biofilm, as one of the critical biological factors in caries formation, should not be neglected in the assessment of caries preventive agents. In this work, the remineralization effectiveness of demineralized human dentin in a multi-species dental biofilm environment via an adhesive containing nanoparticles of amorphous calcium phosphate (NACP) and dimethylaminohexadecyl methacrylate (DMAHDM) was investigated.MethodsDentin demineralization was promoted by subjecting samples to a three-species acidic biofilm containing Streptococcus mutans, Streptococcus sanguinis, Streptococcus gordonii for 24 h. Samples were divided into a control group, a DMAHDM adhesive group, an NACP group, and an NACP + DMAHDM adhesive group. A bonded model containing a control-bonded group, a DMAHDM-bonded group, an NACP-bonded group, and an NACP + DMAHDM-bonded group was also included in this study. All samples were subjected to a remineralization protocol consisting of 4-h exposure per 24-h period in brain heart infusion broth plus 1% sucrose (BHIS) followed by immersion in artificial saliva for the remaining period. The pH of BHIS after 4-h immersion was measured every other day. After 14 days, the biofilm was assessed for colony-forming unit (CFU) count, lactic acid production, live/dead staining, and calcium and phosphate content. The mineral changes in the demineralized dentin samples were analyzed by transverse microradiography.ResultsThe in vitro experiment results showed that the NACP + DMAHDM adhesive effectively achieved acid neutralization, decreased biofilm colony-forming unit (CFU) count, decreased biofilm lactic acid production, and increased biofilm calcium and phosphate content. The NACP + DMAHDM adhesive group had higher remineralization value than the NACP or DMAHDM alone adhesive group.SignificanceThe NACP + DMAHDM adhesive was effective in remineralizing dentin lesion in a biofilm model. It is promising to use NACP + DMAHDM adhesive to protect bonded interface, inhibit secondary caries, and prolong the longevity of restoration.     

Nickel and chromium levels in the saliva of a Saudi sample treated with fixed orthodontic appliances

AimThe aim of this study was to measure the amount of nickel (Ni) and chromium (Cr) released into the saliva of Saudi patients treated with fixed orthodontic appliances.Materials and methodsNinety salivary samples were collected in a cross-sectional manner. Forty samples were collected from patients (17 males, 23 females) with fixed orthodontic appliances after different periods of orthodontic treatment ranging from the first month and up to 32 months into treatment. The fixed orthodontic appliance consisted of 4 bands, 20 stainless steel brackets, and upper and lower nickel titanium or stainless-steel arch wires. The other 50 samples were collected from people without appliances (24 males, 26 females). Samples were analyzed using Inductive Coupled Plasma/Mass Spectrometry and Inductively Coupled Plasma Optical Emission Spectroscopy to measure Ni and Cr levels, respectively. Student’s t-test was used to compare Ni and Cr levels in the treated and untreated control groups.ResultsThe mean Ni level was 4.197 μg/L in the experimental group and 2.3 μg/L in the control group (p < 0.05). The mean Cr level was 2.9 μg/L in the experimental group and 3.3 μg/L in the control group (p < 0.05).ConclusionFixed orthodontic appliances resulted in a non-toxic increase in salivary levels of Ni, but no change in Cr levels. Duration of orthodontic treatment did not affect Ni and Cr levels in the saliva.     

Effects of heat-inactivated Bifidobacterium BB12 on cariogenicity of Streptococcus mutans in vitro

ObjectiveSince some probiotic bacteria are cariogenic themselves, their suitability for caries management is questionable. Inactivated bacteria or their supernatants have been found to exert probiotic effects, whilst having several advantages compared with living bacteria. We hypothesized that viable and heat-inactivated Bifidobacterium animalis BB12 reduces the cariogenicity of Streptococcus mutans (SM) in vitro.DesignWe assessed mono- and mixed species biofilms of SM and viable or heat-inactivated BB12. Biofilms were grown in a continuous-culture-system under cariogenic conditions on smooth proximal enamel or cavitated dentine. For each of eight experimental subsets (4 biofilms × 2 hard-tissue conditions), a total of 32 specimens was used. After 10 days, bacterial numbers of 12 biofilms per group were analysed, and all specimens submitted to transversal microradiography.ResultsMineral loss was higher in cavitated dentine than smooth enamel for all biofilms (p < 0.001, t-test). BB12-monospecies biofilms induced significantly less mineral loss than SM in both enamel (p < 0.05) and dentine (p < 0.001). Viable BB12 did not significantly reduce cariogenicity of SM (p > 0.05), whilst heat-inactivated BB12 decreased cariogenicity of SM in dentinal cavities (p < 0.01). Bacterial numbers were higher on dentine than enamel (p < 0.05), but not significantly influenced by biofilm species (p > 0.05).ConclusionsHeat-inactivated BB12 reduced the cariogenicity of SM in dentinal cavities in vitro. Inactivated probiotics might be suitable for caries control.     

Prevalence of apical periodontitis and quality of root canal treatment in an adult Palestinian sub-population

PurposeThe aim of this study was to determine the prevalence of apical periodontitis and the technical quality of root canal fillings in a Palestinian sub-population.MethodsThe panoramic radiographs of 258 patients (142 females, 116 males) attending dental clinics in 2010 were examined to identify the presence of apical lesions associated with any remaining teeth, excluding third molars. The technical quality of root canal fillings was also evaluated by assessing apical extension from the radiographic apex. The panoramic radiographs were taken by a well-trained radiology assistant and evaluated by a radiologist and an endodontist. Statistical analysis was performed with the chi-square test with a significant level set at P < 0.05%.ResultsOf 6482 teeth examined radiographically, 978 (15.1%) had radiographic signs of apical periodontitis (AP). The prevalence of AP was 8.3% in teeth without filled roots and 59.5% (509/855) in root canal-treated teeth. The prevalence of AP and endodontic treatment increased with age and differed significantly (p < 0.05) between males and females. The majority (74.5%) of root canal fillings was performed inadequately, and most (77.2%) inadequate fillings were >2 mm short of the radiographic apex. The presence of AP was correlated significantly with poorly executed root canal fillings (p < 0.05).ConclusionsThe present study found a high prevalence and incidence of AP in association with root-filled teeth. The technical quality of many root canal treatments was unacceptable.     

The effects of Face mask and Tongue Appliance on Maxillary Deficiency in growing patients: A randomized clinical trial

ObjectivesThe purpose of this randomized trial study was to compare the effects of facemask and Tongue appliance in treatment of Class III malocclusion with maxillary deficiency in growing patients.Materials & methods45 patients (22 males, 23 females) with maxillary deficiency were selected and randomly assigned to 2 groups. 22 patients (10 boys, 12 girls) with the mean age of 9.3 years ± 1.2 years were treated with facemask. 23 patients (12 boys, 11 girls) with the mean age of 10.1 years ± 0.7 years were treated by Tongue appliance. Lateral cephalograms obtained at the beginning and end of the study were analyzed.ResultsPaired t-tests and Wilcoxon test showed that SNA and ANB significantly increased in both groups. Mann-Whitney test showed that there were no statistically significant differences between the two groups except for Jarabak ratio and Upper 1 to SN. U1 to SN increased by 11.1 ± 6.9° in fixed facemask group and 2.5 ± 6.1° in Tongue appliance group (P < 0.001).Both treatment modalities were successful in moving the maxilla forward. However, the upper incisors had more labial inclination in the facemask group.     

Sinonasal melanoma: a systematic review of the prognostic factors

The objective was to evaluate the available published data on sinonasal melanoma and analyse its clinical features, treatment modalities, and prognostic factors. An electronic search was undertaken in March 2018 in multiple databases. Eligibility criteria included publications with sufficient clinical, histological, and immunohistochemical information to confirm the diagnosis. Seventy-three publications (439 cases) were included. The lesion was more prevalent in females than in males. There was a higher prevalence in the seventh and eighth decades of life. The lesions mainly presented as epistaxis and commonly involved the nasal cavity. Age (>67.6 years; P = 0.0012), primary location (middle turbinate; P = 0.0112), disease stage (advanced disease stage; P = 0.0026), treatment (radiotherapy; P = 0.0111), recurrence (recurrence presented; P = 0.0137), and distant metastasis (distant metastasis presented; P = 0.0011) were independently associated with a lower survival rate. Recurrence was significantly correlated with age (>67.6 years; P = 0.0021), sex (males tended to present a higher recurrence rate than females; P = 0.0051), disease stage (stages III and IV presented a higher recurrence rate than stages I and II; P = 0.0331), and histological type (amelanotic lesions presented a higher index of recurrence than melanotic lesions; P = 0.0095). In conclusion, sinonasal melanoma is a neoplasm with a poor prognosis, presenting a 30.69% possibility of survival after 5 years.     

The effect of surface defects in early caries assessment using quantitative light-induced fluorescence (QLF) and micro-digital-photography (MDP)

ObjectivesThe purpose of this study was to consider the impact of surface defects on quantitative light-induced fluorescence (QLF) and micro-digital-photography (MDP) measures, in relationship to lesion depth.MethodsSimulated enamel carious lesions were developed on 45 extracted human teeth. Images of each tooth were captured with both QLF and MDP. The teeth were sectioned and lesion depth was measured with polarized light microscopy (PLM). Pearson correlations were computed using data from the 27 lesions which did not have surface loss, and then separately based upon the 18 lesions which did display surface loss. MDP variables ΔR and ΔX measure reflected light, whereas QLF variables ΔF and ΔQ measure fluorescence.ResultsA strong correlation was identified between lesion depth and ΔF (r = ?0.765, p < 0.0001), and ΔQ (r = ?0.827, p < 0.0001) on intact lesions while a weak but suggestive, although non-significant, correlation was identified between average lesion depth and ΔR (r = 0.369, p = 0.059) and ΔX (r = 0.595, p = 0.0011). However, the corresponding correlation was not statistically significant, when lesions with surface loss were considered for QLF and MDP measures.ConclusionsQLF measures ΔF and ΔQ were strongly correlated with lesion depth in lab-simulated lesions with no surface loss, but not among lesions with surface defects. The two MDP-associated measures, ΔR and ΔX, could not be said to differ significantly when lesions with and without surface defects were compared with lesion depth. Because intact lesions can be remineralized, accurate assessment of their status is imperative for caries treatment.Clinical significanceDental caries is still widely prevalent today. We now know that with early stage detection, remineralization can be accomplished. Being able to identify dental caries in its reversible stage (before physical surface loss) is paramount for the clinician to be able to treat the disease non-invasively.     

Smoking among dental students at King Saud University: Consumption patterns and risk factors

ObjectiveTo assess smoking prevalence among dental students at King Saud University (KSU) and to determine possible risk factors of tobacco use.MethodsA self-addressed invitation letter was sent to all dental students (males and females) at KSU requesting participation in this study. Data on smoking habits, associated risk factors, and demographic factors, such as age, marital status, residency status, the student’s year of study, and grade point average, were collected by an electronic self-administered questionnaire sent via email. Data were analyzed using SPSS. Significant differences between different groups were assessed with a Pearson Chi-Square test at α = 0.05. Logistic regression analysis was used to calculate the odds ratio (OR) and 95% confidence interval (95% CI) and to determine the effect of different risk factors on students’ smoking habits.ResultsOf the 600 registered dental students, 400 students responded (230 males, 170 females), representing a response rate of 67%. More male than female students were current smokers (27.6% vs. 2.4%, p < 0.001). Most smokers used shisha tobacco only (N = 35, 51.5%), followed by both shisha tobacco and cigarettes (N = 17, 25%), or cigarettes only (N = 16, 23.5%). Male students were about 4 times more likely to be smokers if all or most of their friends were smokers compared to students who had some friends who smoked (OR = 3.9, 95% CI = 1.9–7.7). A high proportion of current smokers (47.8%) reported stress as the main reason for smoking. Twenty-six percent of dental students (N = 87) who are currently nonsmokers reported that they have used tobacco at some point in their lives. Over two thirds of sampled students (63%) believed that public tobacco usage is not well addressed in the current college curriculum.ConclusionApproximately one in every four male dental students at KSU is a smoker. Having friends who are smokers was the most important risk factor associated with smoking. There is a general belief among dental students that public tobacco use is not well addressed in the dental college curriculum.     

Effect of honey in preventing gingivitis and dental caries in patients undergoing orthodontic treatment

ObjectivesThis study was conducted to investigate the following: (1) the effects of chewing honey on plaque formation in orthodontic patients, (2) the effect of chewing honey on dental plaque bacterial counts, (3) determine if honey possesses antibacterial effects on bacteria recovered from plaques.MethodsFemale orthodontic patients (n = 20, 12–18 years of age) participated in this randomized controlled study. The effects of honey were compared to treatment with either 10% sucrose or 10% sorbitol that served as positive and negative controls, respectively. The pH of plaque was measured using a digital pH meter prior to baseline and at 2, 5, 10, 20, and 30 min after chewing honey or rinsing with control solutions and the numbers of Streptococcus mutans, Lactobacilli, and Prophymonas gingivalis in respective plaques were determined. The antibacterial activity of honey was tested against commonly used antibiotics using the disk diffusion method.ResultsSignificant differences in pH were observed in the honey and sucrose groups compared to the pH observed in the sorbitol group (p ? 0.001). The maximum pH drop occurred at 5 min in both the honey and sucrose groups; however the pH in the honey group rapidly recovered 10–20 min after exposure and did not drop below the critical decalcification pH of 5.5. On the other hand, the pH following sucrose exposure fell <5.5 and was associated with a 30 min recovery time. The pH observed for the sorbitol group did not change over time. Bacterial counts were significantly reduced in the honey group compared to the other treatment groups (p ? 0.001) and honey significantly inhibited the growth of all studied strains compared to inhibition observed with antibiotics (p ? 0.001).ConclusionsHoney can be used as an alternative to traditional remedies for the prevention of dental caries and gingivitis following orthodontic treatment.