Variation of OXIS contact areas in primary molars among 3-6-year-old children with intraoral digital scanning.

PURPOSE: To determine the variation of OXIS contact areas in primary molars using digital impressions generated from an intraoral scanner (IOS). METHODS: A cross-sectional study was carried out on 214 caries-free posterior quadrants of 80 children (38 males and 42 females) aged 3-6 years. Calibration of taking digital impressions with the IOS procedure was performed initially through scanning of ten quadrants of children to provide a learning environment to the examiner. The digital impressions were then exported, and the type of interproximal contact areas present between the distal surface of the primary first molar and the mesial surface of the primary second molar were identified according to the OXIS classification. The prevalence of the types of OXIS contact areas was expressed in the form of numbers and percentages. The chi-square test was applied to investigate the variability among the arches and to understand the association of OXIS contact areas across age, gender, and arches. RESULTS: The most common contact area type observed was I-type (59.8%), followed by S-type (15.4%), X-type (12.6%), and O-type (12.2%). The I-type contact area was most frequently seen in both males (51.6%) and females (65.5%), while the S-type contact area in males (14.7%) and X-type contact area in females (8.4% each) were the least frequent with no statistical significance between genders (p > 0.05). All three age groups studied showed the highest prevalence of the I-type contact area, which increased with an increase in age (p < 0.05). The inter-arch comparison showed a significant result in terms of the X-type contact area on the right side, and O-type, X-type, and I-type contact areas on the left side, while no statistical difference was seen in the intra-arch comparison for all contact types. CONCLUSION: I-type contact areas were the most prevalent across the arches, age groups and genders.

Evaluation of RURS elbow guard in the management of thumb-sucking habit in children with and without intellectual disability.

BACKGROUND: Digit sucking is a common oral habit among many children, which involves placing the thumb/finger into the mouth, which can cause malocclusion in mixed and permanent dentition. AIM: To evaluate the efficacy of the RURS elbow guard in the management of thumb-sucking habits in children with intellectual disabilities and those without in terms of the mean duration of appliance therapy. The secondary objective was to compare the RURS elbow guard with an intraoral crib in healthy children (without intellectual disabilities) to manage the habit of thumb-sucking. DESIGN: Children with intellectual disabilities and those without between the age of 4 and 16 years were included in the study and categorised into three groups, namely group I (50 normal children; intraoral crib appliance), group II (50 normal children; RURS elbow guard) and group III (50 children with intellectual disabilities; RURS elbow guard). RESULTS: The mean duration of appliance therapy for groups I, II and III were 200.20 ± 20.43 days, 204.34 ± 20.56 days, and 218.43 ± 15.66 days, respectively (p < 0.001). The differences in the mean duration between group I and group II were statistically non-significant, with statistically significant differences between group I and group III (p < 0.001) and between group II and group III (p < 0.05). CONCLUSION: The RURS elbow guard was found to be an efficient appliance in treating thumb-sucking among children who had mild to moderate intellectual disabilities. RURS elbow guard was equally efficient as an intraoral crib appliance in managing thumb-sucking habits in children without intellectual disabilities.

Tooth-surface distribution of caries in Greek schoolchildren, using ICDAS-II index. A national pathfinder survey.

AIM: The objective of this cross-sectional nationwide study was to assess the caries status of Greek children, in regard to the severity and the distribution pattern of the lesions in the primary and permanent dentition at a tooth-surface level, based on ICDAS-II criteria. METHODS: Study Design: A national survey was conducted in 15 urban and 9 rural sites and about 50 subjects were examined at each location across the country. Caries data, based on ICDAS-II index, were recorded on 4,410 children aged 5, 12, and 15-years by 10 calibrated dentists. The rankings of the most affected tooth-surfaces, the most vulnerable teeth found cavitated, the right-left symmetry of caries stages and its pattern of distribution shown per jaw or dentition were determined by using descriptive statistics (SPSS v.20). CONCLUSION: Caries lesions were quite frequent in this school aged child population and the most common code of ICDAS-II observed was that of incipient enamel caries, mainly on the occlusal surfaces, indicative of the need for fissure sealant application. For those surfaces with ICDAS-II=3-6, dental care and intensive prevention programmes, both at home and office based, are needed.

Effectiveness of fissure sealants on initial caries lesions (ICDAS 1-3) of permanent molars: A 4-year follow-up.

AIM: The aim of the present prospective study was to evaluate the retention and effectiveness of two types of sealants (clear vs. opaque) on early pit and fissure occlusal non-cavitated ICDAS II #1-3, caries lesions of permanent posterior teeth of children. MATERIALS AND METHODS: Study Design: 6986 pit and fissure occlusal surfaces were randomly sealed with clear or opaque sealants out of which, 5828 sealants were placed on sound and 1158 on questionable surfaces, while 3508 were clear and 3478 opaque sealants. The mean age of the sample at initial sealant placement was 9.5 (±2.9) years and the follow-up time was 12-48 months. The median (IQR, range) follow-up time was 17.9 (8.7-28.6) months. Study inclusion and exclusion criteria applied to the combined database in order to select the study sample. Teethmate™ F-1 natural and opaque sealants (Kuraray, Hattersheim am Main, Germany) were applied following the standard procedure of preparation with moisture control kept by cotton rolls handled Dri-Angles" and a 30 seconds acid-etch with 37% ortho-phosphoric acid gel was used followed by 10 sec air-water spraying washing and polymerization for 20x2 sec. Sealants were applied on sound tooth surfaces (ICDAS #0) with no visible defects or on surfaces with early caries lesions (ICDAS #1-3), randomly and interchangeably on the upper or lower Jaw. Total retention was considered when all pits and fissures were completely sealed, while partial or complete loss was scored as one code, although was registered separately. STATISTICS: Separate analyses were performed for each type of failure (loss of sealant or restoration). Cumulative probabilities of failure over time after sealant placement, overall or by specific characteristics, were calculated using the Kaplan-Meier method. Association between these characteristics and the hazard of failure were investigated using appropriate Cox proportional hazard models. RESULTS: Sealed surfaces with ICDAS II # 1-3, showed 100% higher probability of having a restoration and 60% higher probability of sealant loss, with both differences being statistically significant (aHR=2.03, p=0.046), adjusted for age, sex, type of sealant and location of surface. Opaque sealants presented statistically significant (p 0.009) higher re-application rate, while fissures had 70% statistically significant (p<0.001) higher probability for resealing with time compared to pits, with gender not affecting sealant retention while the earlier a sealant was placed on children's teeth, the more probable it was to need resealing or restoration (p <0.012). CONCLUSIONS: The therapeutic use of sealants on occlusal surfaces of posterior permanent molars with early carious lesions (ICDAS II 1-3) is inferior compared to sound surfaces, showing higher sealant failures and restorations.

Oral hygiene and periodontal condition of 12- and 15-year-old Greek adolescents. Socio-behavioural risk indicators, self- rated oral health and changes in 10 years.

AIM: To investigate oral hygiene and periodontal status of 12- and 15-year-old Greek adolescents in relation to socio- demographic and behavioural indicators and identify national trends. MATERIALS AND METHODS: In a stratified cluster sample of 2,478 participants, the Simplified Debris Index (DI-S) and the Community Periodontal Index (CPI) were calculated. Socio- demographic/behavioural data were collected through structured questionnaires. Multivariate ordinary regression examined the effect of socio-behavioural indicators on oral hygiene and periodontal conditions. RESULTS: 51.7% of the 12-year-olds and 56.9% of the 15- year-olds had fair and good oral hygiene, respectively. Approximately 30% of the adolescents had healthy periodontium. Bleeding on probing was detected in 23.6% and 21.6% of the 12- and the 15-year-olds, accordingly. Calculus was found in 46.2% and 44.3% of the 12- and the 15-year-old groups, correspondingly. The prevalence of periodontal pockets ?4mm was 3.2%. Significantly higher DI-S scores were found among 12-year-olds who were males, had lower educated mothers or did not use dental floss and among adolescents who brushed their teeth

Regenerative endodontic therapy (RET) for managing immature non-vital teeth: experiences and opinions of paediatric dental practitioners in the European and Arabian regions.

PURPOSE: MTA apical plug approach is considered the gold standard in managing immature teeth with necrotic pulp tissues but does not increase root dimensions. Regenerative Endodontic Therapy (RET) has been advocated as an alternative technique for management of these teeth. This study aimed to assess the knowledge, experience and the opinions of dentists treating paediatric patients in the European and Arabian regions on RET. METHODS: A cross-sectional, pre-piloted 23-item self-administered questionnaire survey was distributed electronically using the Bristol Online Survey tool through the mailing list of the European Academy of Paediatric Dentistry, the Arabian Academy of Paediatric Dentistry's and the Egyptian Society of Paediatric Dentistry. RESULTS: 308 respondents completed the survey. Approximately half practised RET (N = 158; 51.3%), which was most frequently used to manage non-vital traumatized teeth. Majority of RET practitioners worked in university or dental institute practices. Protocol differences with deviation from the current published RET guidelines were observed. Half of the respondents reported discolouration as an undesirable outcome. Lack of training, materials, evidence and suitable cases were reasons for not using RET. CONCLUSIONS: Although RET is being practised by European and Arabian paediatric dentists, different protocols are being used with clear deviations from the current evidence-based guidelines.

Histological validation of the automated caries detection system (ACDS) in classifying occlusal caries with the ICDAS II system in vitro.

AIM: To compare the diagnostic performance of the automated caries detection system (ACDS) for the detection and diagnosis of occlusal caries with the histological appearance of the lesions. METHODS: Eighteen posterior permanent teeth were used, out of which 40 sections were made and 53 areas were evaluated. Teeth with hypoplastic and/or hypomineralised areas or sealants on the occlusal surfaces were excluded from the study. The teeth that were used for this study were a subgroup of the teeth used in the study that introduced ACDS system. This subgroup consisted of teeth having in their occlusal surfaces early carious lesions classified as international caries detection and scoring system (ICDAS) 0, 1, 2 and 3 after clinical examination by the examiners. Histological preparations were classified by experienced examiners based on the Ekstrand, Ricketts and Kidd (ERK) system and for the respective occlusal surfaces by the ACDS system based on ICDAS II system. There were two threshold limits considered as carious in either system ICDAS ≥ 2 or ≥ 3 and ERK index ≥ 2 or ≥ 3 and all possible combinations were analysed. Statistical methods of weighted version of kappa coefficient, Kendall's tau-b correlation coefficient and p-values using the Fisher's exact method were used at the confidence level of 0.05. RESULTS: Intra-examiner kappa coefficient agreement was 0.87 and 0.89 while the inter-examiner for the two trials were 0.87 and 0.92. The ICDAS3-ERK3 combination between the ACDS and histological sections presented the best agreement with kappa coefficient 0.76, agreement 92.5%, sensitivity 100% and specificity 91.1%. ICDAS3-ERK3 combination between the optical examination of the examiners compared to the histological preparations showed kappa coefficient 0.87, agreement 96.2%, sensitivity 100%, Specificity 95.6%. CONCLUSION: The evidence supports the view that ACDS classification of occlusal surfaces based on the ICDAS system are comparable with classification to that of an examiner and with the histology of the lesion. The use of ACDS has the distinct advantage though of removing the subjectivity of the examiner since it performs the classification without any intervention by him.

Recognizing Occlusal Caries in Dental Intraoral Images Using Deep Learning.

Based on an image dataset of 88 in-vivo dental images taken with an intra-oral camera, we show that a Deep Learning model (Mask R-CNN) can detect and classify dental caries on occlusal surfaces across the whole 7-class ICDAS (International Caries Detection and Assessment System) scale. This is accomplished without any image pre-processing method and by utilizing superpixels segmentation for the experts' annotations and the evaluation of the classifier. In the proposed methodology, transfer learning and data augmentation are employed during the training of the model. The paper discusses technical details, provides initial results and denotes points for further improvement by fine-tuning the classifier along with an extended dataset.

Fissure sealant retention and caries development after resealing on first permanent molars of children with low, moderate and high caries risk.

AIM: This was to evaluate the retention of fissure sealants (FS) and their effectiveness after resealing on caries reduction applied to first permanent molars, in a sample of children stratified according to their caries risk status in a private practice setting. METHODS: The sample was 1,274 FS applied on first permanent molars (FPM) of 380 children (6 to 8 years old). Follow-up and monitoring for resealing was 3 years after FS placement, having at least one recall visit per year. Caries risk was based on baseline dmft index: low (dmft=0), moderate (dmft=1-4), high (dmft >4), with almost half of the teeth belonging to the high-risk group. All sealed teeth were evaluated and recorded for FS failure and resealing in case of partial/total loss, as well as caries development. Survival analysis using the Cox Proportional Hazards regression model was used for data evaluation. RESULTS: Of the 1,274 sealed surfaces, 927 (72.8%) needed no intervention 185 (14.5%) needed only resealing and 162 (12.7%) developed caries during the study. Of 162 carious surfaces, 107/ 675 (15.9%) were from the high caries risk children, compared with 17/144 (11.8%) and 38/455 (8.3%) from the moderate and low caries risk group respectively. The highest number of failures, 4.9% and resealing were found at first recall, declining to 1.4% at the end of the study. Development of caries followed a steady rate of 6-8% per year. Cox proportional hazards model indicated, regardless if resealing or caries development was considered a failure or resealing was a success and caries development a failure, only the high dmft index appeared in both cases to significantly increase the chance (158% and 173% respectively) of FS failure and caries development compared with moderate and low dmft index. Other variables when inserted into the hazard model, such as age, sex and number of visits, either did not show a significant effect or only marginally affected FS retention, without modifying the association between caries risk and sealant failure. CONCLUSIONS: Children of a high baseline caries risk status showed lower FS retention rates and higher occlusal caries prevalence following FS loss compared with those of moderate and low risk status. Resealing does not seem to dramatically change the final outcome of the higher risk group to develop more caries, necessitating other more effective measures to increase the retention of FS on these highly vulnerable areas.

Feeding practices of Greek children with and without nursing caries.

PURPOSE: This study was performed to examine the feeding practices and demographic and nursing characteristics of Greek children with and without nursing caries. It was also intended to evaluate what dentists and pediatricians tell parents when they examine children with nursing caries. METHODS: 260 children, ages 3-5 (130 with nursing caries, NC group, and 130 without, NNC group) participated in the study. RESULTS: 95% of the NC group used the bottle at night. In the control, although 85% of the group used the bottle, none of the children developed nursing caries. CONCLUSIONS: 1) The nursing habit of bottle feeding is not the only factor determining the development of nursing caries. 2) Falling asleep with the bottle seems to be the most determinant factor associated with the development of nursing caries. 3) Breastfeeding of the child for more than 40 days may act preventively and inhibit the development of nursing caries in children.

Profile of non-nutritive sucking habits in relation to nursing behavior in pre-school children.

Although a number of investigators have studied the prevalence and etiology of non-nutritive sucking habits in children, no consensus exists among dental and medical experts in respect to the contributing factors and preventing behaviors. Furthermore, changes in the rearing practices of children make management of such habits even more complicated. The purpose of the present study was to investigate finger and pacifier sucking habits among pre-school children, and its possible relationship to nursing behavior. Parental attitudes towards sucking habits were also registered. Questionnaires were sent to parents of 600 children, three to five years old, following an oral examination in a private office. Children attended kindergartens that were randomly selected from the area of Athens, Greece. Questions regarding the nursing patterns-breast or bottle feeding-characteristics of finger and pacifier sucking habits, parental attitudes towards sucking habits, as well as recommendations of the pediatricians were included. Three hundred and sixteen questionnaires were returned by parents. Results indicated that pre-school children discontinued a pacifier sucking habit earlier compared to a finger habit. Pacifiers showed a preventive effect against finger sucking, since only 2% of the sample examined practiced both habits. Breast feeding was not clearly associated with sucking habits; however, long bottle feeding periods were related with decreased finger sucking and high figures of pacifier sucking. The majority of pediatricians were not in favor of an intervention in breaking a finger sucking habit of the child.

Dental injuries of permanent teeth treated in private practice in Athens.

Although there are several epidemiological studies on dental trauma internationally, there are not many studies that record, analyse and follow different kinds of dental trauma treated in a private office, and that evaluate how parameters such as type of dental trauma, as well as time lapse until treatment might influence the final outcome and the prognosis of the teeth. The sample consisted of 242 patients, 6-17 years of age, with 369 injured teeth treated within a period of 5 years. All the case were treated by the first author and were followed for at least 3 years. The treatment modalities used were based upon the clinical examination and the history of the case and included direct and indirect pulp capping, partial pulpotomy, pulpotomy, pulpectomy and splinting. The type of trauma was classified based on WHO classification partially modified. Seventy six percent of the teeth suffered only hard tissue injuries and 22% had only periodontal ligament PDL) trauma. Of the total number of teeth class I represented 3%, class II 59%, class III 20% and class IV 2%. Of the PDL injuries 14% of the teeth suffered concussion, 69% luxation and 17% exarticulation. The highest incidence of dental trauma was observed at the age of 10. Sixty eight percent of the patients sought treatment 3 days or more after the trauma had occurred delayed treatment), while only 32% within the first 3 days (immediate treatment). The main reasons for delayed treatment were neglect (50%) and unawareness 37%). Of the teeth with delayed treatment 43% became necrotic, while only 28% of the teeth that were treated on time needed pulpectomy. Luxations caused more pulp necrosis (46%) than Class I (0%) Class II (7%) or Class III (34%) type of trauma. The data from this study suggested that a most of the dental injuries on permanent teeth were class II or III type, b) a high percentage (68%) of the patients sought treatment more than 3 days after the injury (delayed treatment), c) delayed treatment caused more necrotic teeth, d) the public should be informed of the importance of immediate treatment in an effort to improve the prognosis of the pulp, e) dentists should be informed of the appropriate treatment of dental injuries since 10.3% of the cases were mistreated.

Mercury release from dental amalgams: an in vitro study under controlled chewing and brushing in an artificial mouth.

The release of mercury vapor from class I amalgam restorations prepared in human molar teeth was studied during chewing simulations in an artificial mouth of a bi-axial servo-hydraulic mechanical test system. So that the total mercury released from the restoration over a fixed time could be determined, a closed chamber surrounded the envelope of chewing motion. In addition, the influence of sampling frequency on mercury release was corrected by the use of different sampling frequencies over a fixed time interval of mercury release measurement and extrapolation to zero sampling time. Thus, a combination of a closed environment and an extrapolation method to determine the mercury release under continuous sampling was used to determine the mercury released under normal breathing conditions. The measured mercury release rate data were used to calculate the potential daily mercury dose in a patient due to a single amalgam restoration, following the method previously outlined by Berglund. The mercury release from both a conventional and a high-copper amalgam was evaluated at different age intervals after the restoration was placed in the teeth. The results show that while the age of the amalgam and the amalgam type influence the extent of mercury release during the initial non-steady-state conditions, the steady-state value of mercury daily dose due to a single amalgam filling is 0.03 micrograms/day, which is well below the calculated threshold-limiting value (TLV) of 82.29 micrograms/day considered dangerous for occupational exposure in the United States.