Permanent First Molars Research Articles

Root canal morphology of hypomineralised first permanent molars using micro-CT.

To investigate the root canal morphology of hypomineralised first permanent molars (FPMs) using micro-CT (μCT). Twenty-four hypomineralised FPMs and five clinically sound FPMs were scanned using μCT and assessed using the following parameters: (i) root canal configuration, (ii) connecting canal frequency, (iii) enamel, dentin, and pulp volumes, (iv) cusp tip to pulp horn distance, root canal length, root canal width, and dentin thickness, and (v) the influence of the root canal system landmarks on access cavity outline forms and canal curvature. A two-way repeated-measures analysis of variance was employed with the statistical significance set at p < 0.05. The frequency of accessory and connecting canals was higher in hypomineralised FPMs. Mesio-buccal cusp horn was found to be the closest to its corresponding cusp tip in both groups. There was no significant difference between the root lengths, dentine widths, and pulp space measurements of hypomineralised FPMs compared to clinically sound FPMs. The best angulation to access FPMs was straight-line radicular, along the pulp horn. This study illustrates some variations in the root canal morphology in hypomineralised FPMs compared to clinically sound FPMs. Future studies should focus on assessing these parameters in larger samples.

Factors Associated with Frequency of the First Permanent Molar Caries in Young Children of Multan District, Pakistan Caries in Young Children of Multan District, Paki

Caries is the result of the interaction between tooth surface, microorganisms, and food. The first permanent molar (FPM) is known as the key tooth in the oral cavity and erupts around the age of 6 years. Objective: To determine the frequency of caries in the FPMs in young children and analyze factors associated with FPM caries. Methods: We recruited 350 subjects from different public and private sector schools of Multan District, Punjab, Pakistan, for this cross-sectional study. A predesigned questionnaire was used to collect data from eligible respondents. Dental caries status was assessed visually using a dental mirror, dental explorer, and light. Results: Of the 350 students, 108 were found to be affected with caries, whereas the remaining 242 were caries-free. Among the 108 affected students, 36 were male and 72 were female, and 80 were aged 7–9 years; the remaining 28 students were 10–12 years. Conclusion: Caries frequency varied by parent’s educational level, parent’s socioeconomic status, and also by the age and gender of the child.

Interceptive extractions for first permanent molars: a clinical protocol.

Treatment planning for compromised first permanent molars (FPM) can be difficult. In this paper, we present a clinical protocol to support decision-making. Interceptive loss of an FPM should be considered: where the restoration required to repair the compromised FPM is likely to be large; if the FPM is compromised because of molar-incisor hypomineralisation (MIH); where orthodontics requiring loss of tooth units is planned; or if third permanent molars (TPM) are present. Planning requires careful assessment of the prognosis of the FPM and 8-10 years is the ideal age to do this. If the prognosis is uncertain, the decision of whether or not to extract can be influenced by the presence or absence of the TPM. If the decision to extract the FPM is made, timing is dependent on whether or not extractions will be required as part of orthodontic treatment.

The anticaries effects of pit and fissure sealant in the first permanent molars of school-age children from Guangzhou: a population-based cohort study

BackgroundAnalyses of the effects of pit and fissure sealant have been based on small samples and lack large-scale field evaluation data in China. The aim of this study was to understand the effect of pit and fissure sealant in preventing caries in the first permanent molars (FPMs) of children in Guangzhou.MethodsWe conducted a population-based cohort study using the database of the pit and fissure sealant program of Guangzhou. The carious status and sealant retention of the FPMs were assessed in 4,822 school children who received pit and fissure sealant 3 years prior to the study. The control group included 4,396 children who had indications for receiving pit and fissure sealant but were not treated and were matched according to sex, age and school.ResultsIn the sealant group, the rate of sealant retention in the FPMs was 72.2%. Children in the sealant group had a 37% decreased risk of dental caries compared with the control group (adjusted HR = 0.63 [95% confidence interval (CI), 0.57–0.69], P < 0.001). Compared to no sealant use, the use of pit and fissure sealants reduced the risk of developing dental caries by 44% after 3 years in the FPMs of children from rural areas, reflecting a greater reduction than that among urban children (35%) during the same period (urban: adjusted hazard ratio (HR) = 0.65 [95% CI, 0.58–0.72]; rural: adjusted HR = 0.56 [95% CI, 0.45–0.70], P < 0.001). The mean number of decayed, missing, or filled permanent teeth (DMFT) in the control group was higher than that in the sealant group, and the difference was statistically significant regardless of sex.ConclusionsPit and fissure sealant has a significant preventive effect against dental caries in the FPMs, especially for children in rural areas; thus, this sealant represents an effective technique for preventing and controlling dental caries.

Assessing the Impact of Early Childhood Caries on the Development of First Permanent Molar Decays

Aim: The aim of this study was to evaluate whether the treated and untreated severe early childhood caries (ECC) in children would make any impact on the Permanent First Molar (PFM) decays.Materials and Methods: Our descriptive epidemiological study was conducted in Ataturk University, Faculty of Dentistry, Department of Pediatric Dentistry/Erzurum-Turkey, between 2011 and 2017. We included a total of 90 children (44 girls, 46 boys), and divided them into 3 equal groups. They were 6–9 years old with a mean age of 7.38 ± 0.89. Group 1 consisted of the patients who had previously been treated under GA, Group 2 included the patients with untreated ECC and with no previous dental treatment, and Group 3 consisted of the patients who had been periodically treated in normal clinical settings. Each patient was processed through; dmft scoring and PFM caries evaluation process in accordance with International Caries Detection and Assessment System (ICDAS), respectively. The obtained data was analyzed with SPSS v20.0. And also, we used One-way ANOVA, Kruskal-Wallis and Mann Whitney U tests.Results: In accordance with ICDAS, we found that Group 3 had the highest mean number of PFMs (2 ± 1.43) and Group 2 had the lowest (1.43 ± 1.45). In Group 2, the number of ICDAS-determined carious PFMs were significantly lower than the other groups (p < 0.05). However, ICDAS score 6 was 0 in Group 1, while it was determined higher as 4.2% in Group 2.Conclusion: In respect to our research outcomes, which revealed that regardless of treated or not severe ECC had a significant impact on the PFMs, we strongly recommend that the parent of the children experiencing ECC should be informed about the risk of future caries in PFMs.

Dental root abnormalities in four children with PHACE syndrome

PHACE(S) syndrome is a condition characterized by posterior fossa malformations, hemangiomas, arterial anomalies, cardiac defects, eye abnormalities, sternal cleft, and supraumbilical raphe. We present four children with PHACE(S) syndrome who have absence of or severe malformation of the roots of their permanent first molars (PFMs). Root abnormalities in the children's molars were bilateral and not restricted to the segments affected by cutaneous hemangioma. The reason for root abnormalities is unknown, but given the rarity of these findings in healthy children, it is likely an additional dental manifestation of PHACE syndrome. The absence of functional roots in the PFMs can result in significant consequences. Therefore, we recommend a panoramic dental radiograph during transitional dentition for children with PHACE syndrome to screen for dental root abnormalities.

COMPARING THE EFFECTIVENESS OF HYFLEX ROTARY AND HAND – OPERATED&amp;NBSP; INSTRUMENTS IN PREPARING MESIO-BUCCAL ROOT CANALS OF MANDIBULAR PERMANENT FIRST MOLARS

Objectives: To compare the effectiveness of Hyflex rotary and NiTiflex hand-operated instruments in regard to 4 parameters of root canal preparation: the working time, the alteration of canal curvature and working length, obturating efficacy. Materials and methods: A total of 20 mesio-buccal root canals of mandibular first molars were randomly divided into two similar groups. Group 1 root canals were prepared with Hyflex rotary files according to the manufacter’s instructions. Group 2 with NiTi manual instruments in crown-down technique. Based on radiographs taken prior to instrumentation with the initial instruments inserted into the canals, the 2 groups were balanced with respect to the angle of canal curvature and working length. Canals were prepared using a crown - down preparation technique as instructed by the manufacturer. Group 1 was prepared by rotary Hyflex files and group 2 was prepared by NiTiflex hand-operated instruments. The assessment of changes of canal curvature and working length was based on radiographs taken prior and post instrumentation. The time required for canal preparation was recorded for each specimen. Postoperative teeth were examined clinically and radiographically after 1 week and 3 months. Research design was prospective clinical trials, group comparison. Data was statistically analysed using the SPSS 16.0 software. Results: Rotary Hyflex files prepared significantly faster and maintained the original canal curvature better than hand - operated Nitiflex files (p &lt; 0.05). There was no significant differences in maintaining initial working length of two groups (p &gt; 0.05) and both hand NiTiflex and rotary Hyflex instruments showed 1 case of ledge formation for each, 1 NiTiflex file separation and no perforation or apical transportion. Three-month clinical results were equal: in rotary Hyflex group, 90% teeth of successful result, 10% teeth in suspect; in NiTiflex hand-operated group, 80% ratio of successfully- treated teeth, 10% suspect and 10% failing result. Conclusions: Under the conditions of this clinical study, both instruments were safe to use, showed equally efficacy in preparing root canals and endodontic clinical results. However, rotary Hyflex significantly reduced working time and respected original canal curvature better than hand–operated NiTiflex files, with higher treatment cost from 9 to 10 times. Key words: cleaning, shaping, root canals, rotary, canal curvature

Molar Incisor Hypomineralization: prevalence and severity among children from Nothern Poland.

The aim of this study was to determine the prevalence and severity of molar incisor hypomineralisation in 6-12-year-old children living in Northern Poland. The study involved 1437 children aged 6 to 12 years. The dental examinations took place at the school and were performed in daytime classroom lighting conditions by a single paediatric dentist. The students were examined with headlamp, oral mirror and dental probe. Teeth were not cleaned or dried before examination. All surfaces of the index teeth were examined and diagnosed MIH according to Weerheijm et al. criteria. The severity was recorded as mild or severe according to EAPD criteria. Of all children, 6.43% exhibited signs of MIH on first permanent molars (FPMs) and in 50% of them permanent incisors (PIs) were also affected. There were differences in the MIH prevalence between genders (5.79% female vs. 6.47% male) and place of living (6.4% rural vs. 5.96% urban), without statistical significance. Girls were more likely to have severe lesions, which was statistically significant. The highest incidence of MIH was found in the group of six-year-olds (11.5%), and the lowest in the group of ten- (2.7%) and twelve-year-old (2,65%). Also MIH occurred statistically more often in children up to 8 years of age, compared with children over 8 years of age (8.24% and 4.24%, respectively). In North Poland the prevalence of MIH is 6.43%.

Does Applying Fluoride Varnish Every Three Months Better Prevent Caries Lesions in Erupting First Permanent Molars? A Randomised Clinical Trial.

To determine the effectiveness of fluoride varnish (FV) in preventing caries lesions on the erupting first permanent molars (FPM) of high-risk children. A randomised parallel-blinded clinical trial was conducted with a sample of 180 children between 6 and 7 years of age with at least one sound erupting FPM attending a public school in the Dominican Republic. Children were randomly assigned to three groups, one control and two experimental groups, which received FV application every 3 or 6 months. All the children received fluoride toothpaste (1450 ppm), toothbrush, diet counseling, and oral health recommendations every three months. The development of caries lesions was assessed at twelve months using ICDAS. A total of 157 children completed the study, of which 51.0% were female. At the end of the study, 53 participants comprised the control group, 54 were included in the every-3-months (3-month) FV group, and 50 belonged to the every-6-months (6-month) FV group. Adjusted ORs were calculated to compare lesion development between the groups. The results showed that the control group was more likely to develop caries lesions in comparison to the 3-month FV group, with an associated AOR of 1.46 (95% CI: 1.18 to 1.81, p = 0.001). Likewise, applying FV every six months as opposed to every three increased the odds of developing caries with a significant AOR of 1.29 (95% CI: 1.03 to 1.64, p = 0.029). FV application every three months can be recommended to prevent caries lesions on the erupting first permanent molars of high-risk populations.

Effects of first permanent molar extractıon on space changes observed in the dental arch using data mining method.

The high incidence of caries in first permanent molars (FPMs) makes premature extraction of these teeth common. The extraction of the permanent teeth results in various changes in the dental arch. The aim of this study was to evaluate space closure, the eruption of second permanent molars (SPMs), and changes in dental arch after extraction of the FPMs. Eruption of 83 SPMs was recorded and radiographically developmental stage of these SPMs in the pre-extraction panoramic radiograph was assessed. Space was measured between the distal surface of the second premolar and the mesial surface of SPM. Out of 55 patients, 28 (50.9%) were males and 27 (49.1%) were females. Thirty-seven (44.6%) of 83 teeth belonged to category 1, 17 (20.5%) teeth belonged to category 2, and 5 (6.02%) teeth belonged to category 3. Although category 4 was not found, 24 (28.9%) teeth were observed to be in category 5. Out of all SPMs, 10.8% represented the ''ideal'' stage of Demirjian's dental development, stage E. In patients who had the FPMs extracted before the eruption of the SPM, it is important with regards to the patients' comfort and health to review the patient regularly and to determine any need for orthodontic treatment.

X-RAY ANALYSIS OF THE MANDIBLE IN PATIENTS WITH CROSSBITE AND MANDIBULAR DISPLACEMENT

Introduction: Significant morphological and aesthetic disabilities of the face, observed during the formation of a cross bite in combination with the displacement of the mandible, prompt the doctors - orthodontists to study carefully the morphogenesis of this anomaly. The aim: Analysis of the mandible structure in patients with a cross bite and lower jaw displac ement based on the analysis of orthopantomograms. Materials and methods: For this study, the orthodontic examination of 20 patients, 18-22 years old, was made they complained about facial asymmetry, displacement of the lower jaw and a violation of the cosmetic centers. A diagnosis of the buccal cross bite form in combination with the displacement of the lower jaw was put according to the Uzhumeckiene classification. The methods used do not contradict the conclusions of the ethics commission. Results: The analysis of the obtained data indicates that the angle of the mandible has more variable (p ≤ 0,05). Go120,8º and 125,1º. Significant of the angles of the canines according to the basal arch of the lower jaw of 102,8º and 105,4º (p≤0.01) and the angle of inclination of the first permanent molars of 89,6º and 91,4º, respectively (p≤0.01). Conclusions: The obtained data indicate that there is no clear correlation between changes in the studied parameters and the localization of anomalies (left-sided, right-sided). Indicators of the angle of the lower jaw are significantly altered from the opposite direction of its displacement. The change in the angles of inclination of the canine and the first permanent molars, as occlusive compensation, is determined reliably. The more the angle of the mandible changes, the more the lower jaw moves in the transversal direction. Perhaps this is due to the asymmetric tone of masticatory muscles.

The Association between Molar-Incisor Hypomineralization and Dental Caries with Socioeconomic Status as an Explanatory Variable in a Group of Finnish Children.

The aim of this study was to investigate if a developmental enamel defect known as Molar-Incisor Hypomineralization (MIH) is associated with dental caries. Socioeconomic status (SES) was examined as a confounding factor between caries and MIH. In this cross-sectional study, 636 children, aged 8 to 13 years, from three towns (two rural areas and one urban area) in Finland were examined for MIH in line with the criteria of the European Academy of Paediatric Dentistry. Caries status for permanent teeth was recorded as decayed, missing and filled teeth (DMFT). Caries experience (DMFT > 0) in the first permanent molars (FPMs) was set as an outcome. SES was determined using a questionnaire completed by parents. The prevalence of MIH was 18.1%. The mean DMFT in FPMs for children with MIH was higher than for their peers, 1.03 ± 1.25 vs. 0.32 ± 0.80 (p = 0.000, Mann-Whitney U test). In a multivariate analysis using the generalized linear mixed model where locality, SES, age and MIH were taken into account as caries risk indicators, MIH was the strongest risk indicator of caries in FPMs (Odds Ratio: 6.60, 95% Confidence Interval: 3.83–11.39, p = 0.000). According to the study results, children with MIH have a higher risk for dental caries than children without MIH.

CONDITION OF FIRST PERMANENT MOLARS AND LEVEL OF CARIOGENIC BACTERIA IN CHILDREN.

06Apr 2018 CONDITION OF FIRST PERMANENT MOLARS AND LEVEL OF CARIOGENIC BACTERIA IN CHILDREN. Hazim Mohamed Rizk. Lecturer in Public health, Pediatric dentistry & Orthodontics department, Al Rass College of dentistry, Qassim University.

Consequences of early extraction of compromised first permanent molar: a systematic review

BackgroundThe aim of this study was to systematically review the literature to determine the sequelae of early extraction of compromised first permanent molars (FPMs) with regard to the skeletal and dental development of 5- to 15-year-old children. Meta-analysis was conducted when applicable.MethodsOur research protocol included a search strategy, inclusion/exclusion criteria, and a data extraction plan. The search engines used were PubMed, Scopus, and Science Direct. Study selection was performed independently by three reviewers. Articles published from 1960 to 2017 were reviewed based on inclusion and exclusion criteria. Meta-analysis was performed to compare space closure between upper and lower arches.ResultsEleven studies fulfilled the inclusion criteria. The consequences were decrease in post extraction space, accelerated development and eruption of second permanents molars (SPMs) and third molars, a decrease in caries and/or fillings on the proximal surfaces of adjacent teeth, lingual tipping and retrusion of incisors, and counter clockwise rotation of the occlusal plane.ConclusionThere were several consequences of early extraction of FPMs, which were related to skeletal and dental development. Our systematic review suggests that comprehensive evaluation of the compromised FPMs should be performed before planning an extraction. The ideal time for FPM extraction is when the SPM is at the early bifurcation stage in order to achieve complete closure of the extraction space by the SPM. Benefits should be weighed over the risks to decrease the risk of unfavorable outcomes as much as possible. However, due to the limited evidence on the outcomes and variables that influence them, high-quality prospective studies are needed.

Prevalence of Dental Caries and Fissure Sealants in the First Permanent Molars among Male Children in Riyadh, Kingdom of Saudi Arabia.

AimsTo evaluate the prevalence of dental caries and the presence of fissure sealants on the first permanent molars (FPMs) among 6 to 9 years old primary school boys in Riyadh, Kingdom of Saudi Arabia.Materials and methodsThe carious status and the presence of fissure sealants on the FPMs were examined in 1844 schoolboys, aged 6-9 years (the first three grades), from 17 randomly selected primary schools in Riyadh city, Kingdom of Saudi Arabia.Chi-square test was used to assess the significance of differences in prevalence and proportions.ResultsA total of 5394 FPMs were assessed in the 1844 children. Eighty-three point five percent of children were caries free. Only 0.8% of the children had at least one fissure sealant applied. At tooth level, the decayed FPMs counted for 10.6%. There was obvious underuse of fissure sealants on the FPMs; 0.5% (n = 25). The caries prevalence in the mandibular FPMs (14.4%), was significantly higher than in the maxillary FPMs, 7.7% (p < 0.01). The proportion of carious FPMs increased with age of the children significantly (p < 0.01). There was no significant difference in the proportion of the presence of fissure sealants among the three different grade/age groups (p > 0.05).ConclusionCaries prevalence in the FPMs was moderate but serious amongst this cohort of young students. This was opposed with very low use of fissure sealants.Clinical significanceCareful examination of the first permanent molars among children is mandatory because of their high caries susceptibility. It is important to increase public and dental professionals’ awareness of the effectiveness of fissure sealants and encouraging more placement.How to cite this article: Aldossary MS, Alamri AA, Alshiha SA, Hattan MA, Alfraih YK, Alwayli HM. Prevalence of Dental Caries and Fissure Sealants in the First Permanent Molars among Male Children in Riyadh, Kingdom Saudi Arabia. Int J Clin Pediatr Dent., 2018;11(5):365-370.

Prevalence of ectopic eruption of first permanent molars in a Turkish population.

PurposeThe aim of this study was to investigate the prevalence and characteristics of ectopically erupting first permanent molars (FPMs) in children attending the clinics of the Pediatric Dentistry Department at İstanbul University.Materials and methodsThis retrospective study was performed using panoramic radiographs of 7,649 patients (3,506 females and 4,143 males) aged from 5 to 11 years. The age and gender of the subjects, the number and location of the ectopic molars, bilateral versus unilateral occurrence, the degree of resorption of the roots of the primary molars, and other associated dental anomalies were assessed. Ectopic eruption was categorized according to a grading system based on the resorption rates of the primary molars.ResultsOf the 7,649 reviewed subjects, 203 (118 males and 85 females) were diagnosed with ectopic eruption of the FPMs, resulting in a frequency of 2.65%. The mean age of the subjects with ectopic FPMs was 6.82±1.25 (range: 5–11) years. Of the 273 ectopic FPMs, 157 (57.5%) were detected in the maxilla and 116 (42.5%) in the mandible. Severe and very severe degrees of ectopic eruption were found to be more common in the maxilla than in the mandible, whereas a moderate degree of ectopic eruption was more prevalent in the mandible (p=0.251).ConclusionTo our knowledge, this is the first study in a Turkish population reporting the prevalence of ectopic eruption of FPMs. Although the difference between the right and the left sides was not significant, the severity of ectopic eruption was different between the maxilla and the mandible.

Incidence of endodontically treated first permanent molar teeth among Saudi children subpopulation

Aim and Objectives: A study was carried out among children to assess the incidence of endodontically treated first permanent molar (FPM) teeth during 4 years in Abha, Saudi Arabia. Materials and Methods: A convenient sample of 65 children, willing to participate was included in the study. Sixty-five children were selected for the study of age 6 years old, having erupted FPM teeth in all quadrants. The panoramic radiographs of the subjects were evaluated for sound, decayed, missing, filled teeth (DMFT), or endodontically treated FPM teeth. The same subjects were followed for 4 years and their orthopantomograms (OPGs) were taken at the age of 10 years. Their OPGs were again examined for sound, DMFT, and endodontically treated teeth. The mothers of these children were asked one question about their awareness regarding the importance of FPM teeth of their children. Data were put to statistical analysis. Results: It was found that all subjects at 6 years of age were having sound FPM teeth in all the 4 quadrants of their oral cavity. The overall incidence of endodontically treated FPMs was found to be 1.2% at age 10 years of the subjects. Conclusion: It was concluded that the incidence of endodontically treated FPM teeth was 1.2%. The incidence of root canal treatment was found to be more in the children whose mothers were not aware about the importance of FPM teeth.

Efficacy of intraosseous local anesthesia for restorative procedures in molar incisor hypomineralization-affected teeth in children

Background:Treatment of teeth affected with molar incisor hypomineralization (MIH) in young patients is challenging due to chronic subclinical pulpal inflammation caused by porous enamel and exposed dentin. Hypersensitivity of the teeth and difficulty in achieving local anesthesia due to altered nerve potential affects the successful completion of the treatment.Aim:The aim of the study was to compare the anesthetic efficacy of the intraosseous (IO) anesthetic technique with conventional local infiltration technique in anesthetizing first permanent molars (FPMs) affected by MIH for restorative procedures in children.Materials and Methods:This randomized controlled clinical trial recruited 54 MIH-affected mandibular or maxillary FPMs requiring restorations or stainless steel crowns. The teeth were randomly allocated to two equal groups to receive either IO injection or buccal infiltration (control), both using 4% articaine. Onset, time required, and pain experienced for administration, need for repeat, efficacy of anesthetic technique, heart rate, and postoperative complications were recorded in both the groups. Collected data were subjected to statistical analysis.Results:Onset was significantly faster and pain experienced during administration was significantly lower with IO technique. Need for repeat of anesthesia was significantly more with infiltration (44.4% vs. 7.4% in IO, P = 0.004). Local infiltration failed to produce profound anesthesia in 74.1% MIH-affected teeth. IO anesthesia profoundly anesthetized 88.9% MIH-affected teeth. Anesthetic efficacy was significantly better with IO anesthesia (P < 0.001). Postoperative complications were significantly lower with IO anesthesia (P = 0.003).Conclusion:IO local anesthesia was found to be an effective and safe technique to achieve profound anesthesia in MIH-affected teeth in children in comparison to local infiltration.

Tooth mineral density of different types of hypomineralised molars: a micro-CT analysis.

This study sought to evaluate the tooth mineral density (TMD) for the different lesion types in hypomineralised first permanent molars (FPMs) and compare them to unaffected enamel in clinically sound FPMs. Eighteen FPMs with varying degrees of hypomineralised enamel were grouped into brown, yellow/creamy and white lesion types. Micro-CT was used to determine the TMD for each lesion type, and for unaffected enamel at different locations in the outer, middle, and inner-third of the enamel. The average TMD for brown, yellow/creamy, white and unaffected enamel was 1.79, 2.21, 2.43 and 2.46g/cm3, respectively. Brown and yellow/creamy lesions exhibited a statistically significant difference when compared to white lesions and unaffected enamel. However, no statistical difference was evident in TMD between white lesions and unaffected enamel. The TMD increased from the outer-third to inner-third for brown and yellow/creamy lesions (p<0.05), while in white lesions and unaffected enamel, the TMD decreased from the outer-third to inner-third (p<0.05). TMD was lowest for brown lesions followed by yellow/creamy lesions while the TMD for white lesions was similar to unaffected enamel.

Risk factors associated with new caries lesions in permanent first molars in children: a 5-year historical cohort follow-up study.

The objective of this study is to analyze the factors associated with the occurrence of caries in the permanent teeth (PT) and in the permanent first molar (PFM) 5years after their eruption. Children born in 2005 and enrolled in a community dental program were included. The inclusion criteria were: age 10years in 2015; the availability of clinical dental history (CDH) data from before eruption of the PT and a follow-up period of 5years after eruption of the PT. A total of 206 children were enrolled. Risk factors evaluated were: caries experience in the mother, educational level of the mother, frequent drug use, systemic diseases, eating habits, brushing frequency, presence of molar incisor hypomineralization (MIH) in PT, and caries in deciduous teeth (DT). Associations between explanatory factors and the DMF-T (decayed, missing, filled teeth in PT) and DMFT-M (DMF in PFM) indexes, independently considering cavitated or cavitated and non-cavitated caries as outcomes, were evaluated by poisson regression with robust variance analysis. In the multivariate analysis, a cariogenic diet, especially soft drinks, was associated to high DMF-T and DMFT-M scores when both cavitated and non-cavitated caries were considered. A brushing frequency <1 a day was significantly associated to high DMF-T scores. The presence of df-t (decayed and filled temporary teeth) score >0 and MIH conditioned high DMF-T or DMFT-M values, considering cavitated or cavitated and non-cavitated caries. The intake of sweets and soft drinks, brushing frequency, caries in DT, and MIH in PT were the best predictors of caries in PT. Control of risk factors in early childhood is important for preventing caries in PT.