Evaluating the precision and accuracy of digital dental models with a low-cost structured light device.

OBJECTIVE: This study evaluated the accuracy and precision of digital models acquisition using a home-built, low-cost scanning system based on the structured light method. METHODS: a plaster model (PM) was scanned using the experimental device (SL) and a dental desktop scanner (DS). The teeth dimensions of PM and SL models were measured in triplicate, with a caliper and digitally, respectively. The agreement of the measurements of each model was evaluated using the intraclass correlation coefficient, and the validity between the different measurement techniques was assessed using the Bland-Altman analysis. The accuracy and precision of the models were qualitatively investigated using the mesh superposition of the SL and DS models. RESULTS: A high intraclass correlation coefficient was observed in all models (PM=0.964; SL1=0.998; SL2=0.995; SL3=0.998), and there was no statistical difference between the measurements of the SL models (p>0.05). PM and SL model measurements were found to be in good agreement, with only 3.57% of the observed differences between the same measurement being located outside 95% limits of agreement according to Bland and Altman (0.43 and -0.40 mm). In the superimpositions of SL-SL and SL-DS models, areas of discrepancy greater than 0.5 mm were observed mainly in interproximal, occlusal, and cervical sites. CONCLUSION: These results indicate that the home-built SL scanning system did not possess sufficient accuracy and precision for many clinical applications. However, the consistency in preserving the dental proportions suggests that the equipment can be used for planning, storage, and simple clinical purposes.

Retrospective Follow-up Assessment of Risk Variables Influencing the Outcome of Autologous Tooth Transplantation.

INTRODUCTION: This retrospective study aimed to identify which patient-, donor tooth-, recipient site-, and surgical procedure-related variables may influence the outcome of tooth autotransplantation. METHODS: The sample included 128 autotransplants performed in 122 patients. Single-visit clinical/imaging examinations were used to define the outcome as successful, survival, or failure. The association of potential indicators with the survival or failure categories was analyzed individually and adjusted for confounders through multivariate logistic regression models. RESULTS: After a follow-up period of 1 to 30.11 years, success was achieved in 71.8% of autotransplants, whereas the survival and failure groups had rates of 14.1% each, and the grouped success/survival rate reached 85.9%. An extraoral time >15 minutes and difficult handling/placement were strong/independent risk covariates for survival and failure categories (odds ratio >1, P < .05). Additionally, unerupted/partially erupted status of the donor tooth was a significant indicator for survival, whereas deficient bone level at the recipient site, surgical extraction, poor initial stability, and lack of prophylactic antibiotics were independently linked to failure (odds ratio > 1, P < .05). The root morphology and socket status acted as modifiers of the effect of the recipient site location on the survival group (P > .05). CONCLUSION: Based on the results of this study, unerupted/partially erupted status of the donor tooth, surgical extraction, total extraoral time >15 minutes, deficient recipient's bone level, difficult handling/placement of the autotransplant, poor initial stability, and lack of prophylactic antibiotics during the surgical procedure must be considered with caution when performing autotransplantation because of their deleterious influence on the outcome.

Trueness of Crown Preparation Dies in Dental Models: An In Vitro Assessment of Digital and Analog Workflows.

PURPOSE: To assess crown die trueness using additive manufacturing (AM) based on intraoral scanning (IOS) data and compare it with stone models. MATERIALS AND METHODS: Crown dies with four finish line types- equigingival shoulder (SAE), subgingival shoulder (SAS), equigingival chamfer (CAE), and subgingival chamfer (CAS)-were incorporated into a reference model and scanned with a coordinate measurement machine (CMM; n = 1 scan). Trios4 (3Shape) scans generated a second reference dataset (IOS; n = 10 scans). Using scans, crown dies were produced with two different 3D printers (MAX UV385 [Asiga] and NextDent 5100 [3DSystems]; n = 10 per system). Stone dies were created from conventional impressions (n = 10). Specimens were digitized with a laboratory scanner (E4, 3Shape). Trueness was evaluated with Geomagic Control X (3DSystems). Data analysis was done using Shapiro-Wilk, Levene, ANOVA, and t tests (α < .05). RESULTS: All crown dies fell within the clinically acceptable trueness range (150 µm). IOS exhibited significantly lower (P < .05; Δ ≤ 21.7 µm) or similar trueness compared to stone models. Asiga dies demonstrated similar and NextDent significantly lower marginal trueness than IOS (P < .05; Δ ≤ 57.3 µm). Most AM margin areas had significantly lower trueness than stone (P < .001; Δ ≤ 57.2 µm). Asiga outperformed NextDent (P < .001). Shoulder trueness surpassed chamfer in optical scans (P = .01). Finish line design and gingiva location did not have a significant impact on AM and stone models (P > .05). CONCLUSIONS: Combining IOS and AM achieves clinically acceptable crown die trueness for single molar teeth. The choice of AM device is critical, with Asiga outperforming NextDent. Finish-line design has an impact on optical scans. Finish-line design and marginal gingiva location have little effect on AM trueness.

Combining public datasets for automated tooth assessment in panoramic radiographs.

OBJECTIVE: Panoramic radiographs (PRs) provide a comprehensive view of the oral and maxillofacial region and are used routinely to assess dental and osseous pathologies. Artificial intelligence (AI) can be used to improve the diagnostic accuracy of PRs compared to bitewings and periapical radiographs. This study aimed to evaluate the advantages and challenges of using publicly available datasets in dental AI research, focusing on solving the novel task of predicting tooth segmentations, FDI numbers, and tooth diagnoses, simultaneously. MATERIALS AND METHODS: Datasets from the OdontoAI platform (tooth instance segmentations) and the DENTEX challenge (tooth bounding boxes with associated diagnoses) were combined to develop a two-stage AI model. The first stage implemented tooth instance segmentation with FDI numbering and extracted regions of interest around each tooth segmentation, whereafter the second stage implemented multi-label classification to detect dental caries, impacted teeth, and periapical lesions in PRs. The performance of the automated tooth segmentation algorithm was evaluated using a free-response receiver-operating-characteristics (FROC) curve and mean average precision (mAP) metrics. The diagnostic accuracy of detection and classification of dental pathology was evaluated with ROC curves and F1 and AUC metrics. RESULTS: The two-stage AI model achieved high accuracy in tooth segmentations with a FROC score of 0.988 and a mAP of 0.848. High accuracy was also achieved in the diagnostic classification of impacted teeth (F1 = 0.901, AUC = 0.996), whereas moderate accuracy was achieved in the diagnostic classification of deep caries (F1 = 0.683, AUC = 0.960), early caries (F1 = 0.662, AUC = 0.881), and periapical lesions (F1 = 0.603, AUC = 0.974). The model's performance correlated positively with the quality of annotations in the used public datasets. Selected samples from the DENTEX dataset revealed cases of missing (false-negative) and incorrect (false-positive) diagnoses, which negatively influenced the performance of the AI model. CONCLUSIONS: The use and pooling of public datasets in dental AI research can significantly accelerate the development of new AI models and enable fast exploration of novel tasks. However, standardized quality assurance is essential before using the datasets to ensure reliable outcomes and limit potential biases.

[The assessment of the endodontic foundation]. / De beoordeling van het endodontische fundament.

The diagnosis of an endodontic disease requires thorough research, collecting both clinical and radiographic information. The clinical examination includes history taking, visual inspection of the tooth and surrounding tissues, palpation of the soft and hard tissues, periodontal examination and percussion. The radiographic examination provides valuable information, but can never stand alone in arriving at a diagnosis. It is important to link the findings of the radiographic examination to other information. Sometimes, invasive examination is necessary, during which the coronal restoration is removed to allow better assessment of the tooth. This can provide additional information about the presence of caries, fractures, leakage of the restoration or other reasons for failure of the initial root canal treatment. A good diagnosis is essential for planning successful follow-up treatment.

Assessment of the efficiency of DNA isolation and profiling applying a temperature-driven method in human remains.

The identification of human remains is of utmost importance in a variety of scenarios. One of the primary identification methods is DNA. DNA extraction from human remains could be difficult, particularly in situations where the remains have been exposed to environmental conditions and other insults. Several studies tried to improve extraction by applying different approaches. ForensicGEM Universal (MicroGem) is a single-tube approach to DNA extraction and a temperature-driven method that could have some advantages with respect to previous techniques, among them, reducing the risk of contamination, not requiring specialized equipment, or several steps to perform. The aim of this study was to assess, for the first time, the efficiency of DNA extraction and quality of STR profiles applying the MicroGem protocol and modifications of this protocol from tooth samples in comparison with automatic extraction (AE). Our results indicated that AE and MicroGem performed similar, though with variability depending on the MicroGem modifications, increasing the DNA yield and STR profile quality when DNA is concentrated with Microcon. These findings demonstrated the efficiency of this methodology for DNA extraction from human remains while also providing a simple and quick technique suitable to apply in a variety of forensic scenarios.

Assessment of an online tooth morphology course and 3D examination tool during the COVID-19 pandemic.

INTRODUCTION: The COVID-19 pandemic brought major disruptions to dental teaching and has impacted the delivery of tooth morphology courses where students are introduced to the three-dimensional features of the dentition. The aim of this study was to assess the implementation of newly developed online teaching modalities for tooth morphology, evaluate their usefulness and identify elements that are beneficial for learners. MATERIALS AND METHODS: Following the delivery of an online course that included online 3D models, 2D cue cards, live discussion sessions and Socrative™ quizzes, the participants were asked to rate the usability and usefulness of each tool. The participants' knowledge of tooth morphology was assessed through an online examination using 3D-digitised tooth models. RESULTS: The participants identified lecture handouts and online 3D models as their preferred learning tools, while lecture video recordings and 2D cue cards were viewed as less useful. Data analysis from Socrative™ quizzes demonstrated improvement in tooth identification skills throughout the course delivery. Finally, results from the final assessment are in line with previous in-person deliveries of this course. CONCLUSIONS: The study provides valuable information on the usefulness of teaching modalities that were implemented in response to the COVID-19 pandemic and their merit to be retained in future deliveries of the course. The 3D models have been identified as particularly useful in this context, but the participants still value the opportunity to learn with extracted teeth. Furthermore, it remains to be confirmed whether tooth identification skills acquired using 3D models can be transferred to the clinical setting.

Reconstruction of dental roots for implant planning purposes: a retrospective computational and radiographic assessment of single-implant cases.

PURPOSE: The aim of the study was to assess the deviation between clinical implant axes (CIA) determined by a surgeon during preoperative planning and reconstructed tooth axes (RTA) of missing teeth which were automatically computed by a previously introduced anatomical SSM. METHODS: For this purpose all available planning datasets of single-implant cases of our clinic, which were planned with coDiagnostix Version 9.9 between 2018 and 2021, were collected for retrospective investigation. Informed consent was obtained. First, the intraoral scans of implant patients were annotated and subsequently analyzed using the SSM. The RTA, computed by the SSM, was then projected into the preoperative planning dataset. The amount and direction of spatial deviation between RTA and CIA were then measured. RESULTS: Thirty-five patients were implemented. The mean distance between the occlusal entry point of anterior and posterior implants and the RTA was 0.99 mm ± 0.78 mm and 1.19 mm ± 0.55, respectively. The mean angular deviation between the CIA of anterior and posterior implants and the RTA was 12.4° ± 3.85° and 5.27° ± 2.97° respectively. The deviations in anterior implant cases were systematic and could be corrected by computing a modified RTA (mRTA) with decreased deviations (0.99 mm ± 0.84 and 4.62° ± 1.95°). The safety distances of implants set along the (m)RTA to neighboring teeth were maintained in 30 of 35 cases. CONCLUSION: The RTA estimated by the SSM revealed to be a viable implant axis for most of the posterior implant cases. As there are natural differences between the anatomical tooth axis and a desirable implant axis, modifications were necessary to correct the deviations which occurred in anterior implant cases. However, the presented approach is not applicable for clinical use and always requires manual optimization by the planning surgeon.

Asymmetry in Class II subdivision malocclusion: Assessment based on 3D surface models.

INTRODUCTION: There is currently no consensus in the literature whether the aetiology of a Class II subdivision is dental, skeletal or both. The aim of this study was to identify and quantify skeletal and dental asymmetries in Class II subdivision malocclusions. METHODS: CBCTs from 33 Class II subdivision malocclusion patients were used to construct 3D volumetric label maps. Eighteen landmarks were identified. The original scan and associated 3D volumetric label map were mirrored. Registration of the original and mirrored images relative to the anterior cranial base, maxilla and mandible were performed. Surface models were generated, and 3D differences were quantified. Statistical analysis was performed. RESULTS: Anterior cranial base registration showed significant differences for fossa vertical difference, fossa roll, mandibular yaw, mandibular lateral displacement and lower midline displacement. Regional registrations showed significant differences for antero-posterior (A-P) mandibular length, maxillary roll, A-P maxillary first molar position, maxillary first molar yaw and maxillary first molar roll. Class II subdivision patients also show an asymmetric mandibular length as well as an asymmetric gonial angle. Moderate correlations were found between the A-P molar relationship and fossa A-P difference, mandibular first molar A-P difference, maxillary first molar A-P difference and maxillary first molar yaw. CONCLUSIONS: This study suggests that Class II subdivisions can result from both significant skeletal and dental factors. Skeletal factors include a shorter mandible as well as posterior and higher displacement of the fossa on the Class II side, resulting in mandibular yaw. Dental factors include maxillary and mandibular first molar antero-posterior asymmetry.

Effect of argon plasma abutment activation on soft tissue healing: RCT with histological assessment.

OBJECTIVE: To assess the peri-implant soft tissue profiles between argon plasma treatment (PT) and non-treated (NPT) healing abutments by comparing clinical and histological parameters 2 months following abutment placement. MATERIALS AND METHODS: Thirty participants were randomly assigned to argon-plasma treatment abutments group (PT) or non-treated abutments (NPT) group. Two months after healing abutment placement, soft peri-implant tissues and abutment were harvested, and histological and clinical parameters including plaque index, bleeding on probing, and keratinized mucosa diameter (KM) were assessed. Specialized stainings (hematoxylin-eosin and picrocirious red) coupled with immunohistochemistry (vimentin, collagen, and CK10) were performed to assess soft tissue inflammation and healing, and the collagen content keratinization. In addition to standard statistical methods, machine learning algorithms were applied for advanced soft tissue profiling between the test and control groups. RESULTS: PT group showed lower plaque accumulation and inflammation grade (6.71% vs. 13.25%, respectively; p-value 0.02), and more advanced connective tissue healing and integration compared to NPT (31.77% vs. 23.3%, respectively; p = 0.009). In the control group, more expressed keratinization was found compared to the PT group, showing significantly higher CK10 (>47.5%). No differences in KM were found between the groups. SIGNIFICANCE: PT seems to be a promising protocol for guided peri-implant soft tissue morphogenesis reducing plaque accumulation and inflammation, and stimulating collagen and soft tissue but without effects on epithelial tissues and keratinization.

Optical impressions assessment for overlay restorations with rubber dam: A clinical trial.

OBJECTIVE: The possibility of making impressions of teeth prepared with a rubber dam in place has been proposed; however, this requires trimming and rescanning the mesh, which has been described as a cause of accuracy loss. This study aims to clinically determine whether overlay restorations obtained from a scan with a rubber dam in place have equivalent marginal fit, contact points, and occlusal fit to the same type of restorations obtained from a scan without a rubber dam. MATERIAL AND METHODS: Thirty patients who underwent overlay restoration of a molar with at least one neighbouring tooth were selected. After tooth preparation, two scans were performed: one without a rubber dam and the other with a rubber dam. Restorations were randomly created from one scan or another. The marginal fit, interproximal contact points, and occlusal fit were evaluated clinically. Two meshes, with and without rubber dams, were also compared. RESULTS: No significant differences were observed in the clinical evaluation of the overlays made of the two meshes. The trueness of the mesh from the impression made with a rubber dam with respect to the mesh without a rubber dam was about 40 µm in the critical areas of the preparation (margins, intaglio, and interproximal contact points). CONCLUSIONS: The results of this study show that under the conditions performed and with the equipment used, there are no significant clinical differences between overlay restorations made from a scan with a rubber dam and those made from a scan without a rubber dam. CLINICAL SIGNIFICANCE: Scanning with a rubber dam in place may be a valid option for certain types of restorations under certain clinical conditions.

Comparative Assessment of Three Different Alveolar Ridge Dimension Measurement Methods before Implant Placement: An In Vivo Study.

AIM: The purpose of this study was to compare the three various techniques for measuring the alveolar ridge's dimensions prior to implant insertion. MATERIALS AND METHODS: For this study, a total of 36 participants were chosen. To prepare a surgical stent, a study model was created from an alginate impression. A first point (reference point) was marked on the crest of the ridge in relation to the adjacent teeth. Then, one point (point 1) and another point (point 2) were marked at distances of 3 and 6 mm, respectively, from the reference point. Based on the procedure for measuring the size of the alveolar ridge, the study was divided into the following groups. Group I: Cone-beam computed tomography (CBCT) measurement method; Group II: Ridge mapping measurement method; Group III: Direct caliper measurements method. Descriptive statistics were used to estimate the mean and standard deviation (SD). The Student's unpaired t-test was utilized for the statistical analysis. The 5% level of significance was used. RESULTS: There was no significant difference found between CBCT with ridge mapping and direct caliper measurements. However, on comparison of ridge mapping and direct caliper measurements technique, at point 1, the ridge mapping was 3.88 ± 0.12 and the direct caliper measurement was 3.62 ± 0.08. At point 2, the ridge mapping was 6.58 ± 0.06 and the direct caliper measurement was 6.32 ± 0.04. There was a statistically significant difference found between these two measurement methods. CONCLUSION: Within the limitation, the current study came to the conclusion that when CBCT and ridge mapping measurements were individually compared with the gold standard-the surgical open method, CBCT-demonstrated to be a highly specific and sensitive method for detecting the residual alveolar ridge width in the treatment planning of dental implants. CLINICAL SIGNIFICANCE: Evaluation of alveolar bone is necessary during treatment planning for dental implant placement. Using simply panoramic and/or periapical radiographs to evaluate the bone may not be sufficient because it only provides two-dimensional information regarding the implant locations. Therefore, for better implant placement, three-dimensional information of the implant site, such as CBCT and ridge mapping technique, should be assessed.

Assessment of early childhood caries using ICDAS and Snyder caries activity test among preschool children: a cross-sectional study.

The aim of the present study was to elucidate the correlation between the International Caries Detection and Assessment System (ICDAS) and the Snyder caries activity test (SCAT) for the assessment of early dental caries in preschool children. Dental health status of 153 children aged 3-5 years was evaluated by oral examination. The ICDAS stage (enamel opacity stage to cavitated dentine caries stage (stages 1-6)) was assigned based on the evaluation of each tooth surface by a trained dentist based on the number of decayed (d) and filled teeth (ft). In this study, scores of d3-6t (t, teeth), d3-6s (s, tooth surface), d3-6ft and d3-6fs were the cut-off points for enamel caries, set to ICDAS code 3 (d3). SCAT score was assigned based on the acid production level of lactic acid bacteria in plaque (scores: 1-4). Linear correlation analysis was used to determine the correlation between ICDAS and SCAT scores. The proportion of children for each of the dental caries status were as follows: d0, 46.4%; d1-2, 28.1%; d3-4, 9.8%; d5-6, 15.7%. Regarding SCAT scores, 30%, 30.1%, 26.8% and 12.4% children had no, mild, moderate and severe caries activity, respectively. The d3-6t, d3-6s, d3-6ft and d3-6fs indices increased with age and were 0.56, 0.82, 2.03 and 5.05, respectively. Children with a higher SCAT score had higher ICDAS scores (p < 0.05). Our findings suggest that a combination of ICDAS and SCAT scores is beneficial for diagnosing caries progression and highly active caries. Early childhood caries should be managed early to prevent the enamel opacity stage to progress to cavitation.

Assessment of early dental arch growth modification with removable maxillary expansion by cone-beam computed tomography and lateral cephalometric radiographs: a retrospective study.

BACKGROUND: This study evaluated the skeletal and dental changes of patients brought by early removable maxillary expansion (ERME) treatment to explore the clinical treatment effect of ERME on early dental arch growth modification. METHODS: Subject children aged 6-10 years with a maxillary transverse deficiency received ERME treatment, cone-beam computed tomography (CBCT) and lateral cephalometric radiographs were measured before and after treatment, and statistical differences in the measured items were evaluated with corresponding statistical methods to explore the skeletal and dental changes. RESULTS: After ERME treatment, there was a statistical increase in the maxillary basal bone arch width, nasal cavity width, maxillary alveolar bone arch width, and maxillary dental arch width. A buccal inclination of the maxillary alveolar bone and a buccal inclination and buccal movement in the alveolar bone of maxillary first molars were found. The maxillary skeletal expansion was statistically greater than the dental expansion. Increases in the mandibular alveolar bone arch width and dental arch width happened after treatment. A decrease in angle ANB and an increase in Ptm-A, U1-SN, U1-PP, L1-MP, and L6-MP were found after treatment. No statistical changes in the growth pattern-related measured items were observed. CONCLUSIONS: ERME could expand the maxillary basal bone arch width, nasal cavity width, maxillary alveolar bone arch width, and maxillary dental arch width. The maxillary skeletal expansion was greater than the dental expansion. Secondary increases in the mandibular alveolar bone and dental arch widths would happen after ERME. ERME would result in a mandibular advancement, a labial inclination of maxillary anterior teeth, and an increase of maxillary sagittal length, and would not change the patient's growth pattern. TRIAL REGISTRATION: This study was approved by the Institutional Review Board of the West China Hospital of Stomatology, Sichuan University. (WCHSIRB-D-2020-446).

Isotopic and proteomic evidence for communal stability at Pre-Pottery Neolithic Jericho in the Southern Levant.

As one of the key, long-term occupied sites in the Southern Levant, Jericho was one of the most important early Neolithic centres to witness social and economic changes associated with the domestication of plants and animals. This study applies strontium (87Sr/86Sr), oxygen (δ18O) and carbon (δ13C) isotope analyses to the enamel of 52 human teeth from Pre-Pottery Neolithic (PPN) layers of Jericho to directly study human diet and mobility and investigate the degree of consolidation and the flexibility of social organization of Jericho society in the PPN period. The results indicate only two non-local individuals out of the 44 sampled inhabitants identified by strontium isotope analysis and are consistent with the presence of a largely sedentary community at PPN Jericho with no evidence for large-scale migration. We also construct strontium spatial baselines (87Sr/86Sr map) with local 87Sr/86Sr signatures for the sites across the Southern Levant based on systematic compilation and analysis of available data. In addition, we apply proteomic analysis of sex-specific amelogenin peptides in tooth enamel for sex estimation of the sampled individuals (n = 44), the results of which showed a sex-biased ratio (more male than female detected in this sample pool) in Jericho society during the PPN period, which may be due to the limited sample size or selective ritual practices like particular burial zones used for specific groups. We also pretreated a batch of human bone samples recovered from PPNB Jericho for stable carbon and nitrogen isotope analyses for dietary investigations. However, the extracted collagen showed poor preservation and no valid δ13C or δ15N data were obtained.

Investigating mobility and pastoralism in Kerma-period communities upstream of the fourth cataract, Sudan.

OBJECTIVES: The Kingdom of Kush in today's northern Sudan and southern Egypt (ancient Nubia) is often depicted as a secondary state relative to ancient Egypt. More recent investigations have set aside Egyptocentric and western, colonialist perspectives of state development focused on control of land and agricultural surplus, examining Kushites through the lens of African-based models of mobile pastoralism in which power and authority were achieved through control of herds and alliance-building. Here, analyses of radiogenic strontium isotopes in human dental enamel are used to investigate diachronic shifts in mobility patterns linked to pastoralism and state development during the Kerma period (ca. 2500-1100 BCE). MATERIALS AND METHODS: From five cemetery sites around al Qinifab, Sudan, upstream of the capital at Kerma, we analyzed the strontium isotope ratios of 50 teeth from 27 individuals dating from the Early through Late Kerma phases. RESULTS: Individuals from the Early and Middle Kerma phases demonstrated considerable 87 Sr/86 Sr ratio variability (mean = 0.70835 ± 0.00109), with 50% falling outside the locally bioavailable strontium range. Conversely, most Classic (0.70756 ± 0.00043) and Late Kerma (0.70755 ± 0.00036) individuals exhibited ratios consistent with the local region. DISCUSSION: These changes indicate a potential transformation in subsistence strategies and social organization as early communities engaged in a more mobile lifestyle than later groups, suggesting a greater degree of pastoralism followed by declining mobility with Kushite state coalescence and a shift to agropastoralism. Because 87 Sr/86 Sr ratios from enamel reflect childhood geographic residence, these findings indicate that mobility likely involved extended family groups, and not just transhumant adults.

Microcomputed Tomography Mineral Density Profile as Reference Standard for Early Carious Lesion Activity Assessment.

Early caries diagnosis is crucial to treatment decisions in dentistry and requires identification of lesion activity: whether a carious lesion is active (progressively demineralizing) or arrested (progressively remineralizing). This study aimed to identify microtomographic (micro-CT) differences between active and arrested smooth surface enamel lesions, to quantify those micro-CT differences by creating thresholds for ex vivo caries activity assessment to serve as a future reference standard, and to validate those thresholds against the remaining sample. Extracted human permanent teeth (n = 59) were selected for sound surfaces and non-cavitated smooth surface carious lesions. Each surface was then examined for caries activity by calibrated individuals via visual-tactile examination using the International Caries Classification and Management System (ICCMS) activity criteria. Each tooth was scanned via micro-CT and the mineral density was plotted against lesion depth. The area under the curve (AUC) was calculated and represented the loss of density for the outermost 96 µm of enamel. AUC thresholds obtained from micro-CT were established to classify sound, remineralized, and demineralized surfaces against the gold standard examiner's lesion assessment of sound, inactive, and active lesions, respectively. The established AUC thresholds demonstrated moderate agreement with the assessment in identifying demineralized lesions (k = 0.45), with high sensitivity (0.73) and specificity (0.77). This study demonstrated quantifiable differences among demineralized lesions, remineralized lesions, and sound surfaces, which contributes to the establishment of micro-CT as a reference standard for caries activity that may be used to improve clinical and laboratorial dental caries evaluations.

Oral health-related quality of life in patients with oligodontia: A FACE-Q assessment.

OBJECTIVES: The present study aimed to investigate the impact of oligodontia on appearance and on the functional and psychosocial aspects of oral health-related quality of life (OHrQoL) in patients aged 8-29 years. METHODS: 62 patients with oligodontia that were registered at Radboud University Medical Center, Nijmegen, The Netherlands were included. A control group included 127 patients that were referred for a first orthodontic consultation. Participants completed the FACE-Q Dental questionnaire. Regression analyses were performed to explore relationships between OHrQoL and patient-identified gender, age, the number of congenitally missing teeth, active orthodontic treatment, and previous orthodontic treatment. RESULTS: The only clear significant difference between the oligodontia and control groups was that patients with oligodontia scored lower in the domain, 'eating and drinking' (p < 0.001). It was found that, in oligodontia, the greater the number of agenetic teeth, the more difficulties eating and drinking. In fact, the Rasch score was reduced by 1.00 (95% CI: 0.23-1.77; p = 0.012) for each extra agenetic tooth. Older children scored significantly lower than younger ones on five out of nine scales: appearance of the face, smile, and jaws; social function; and psychological function. Females scored significantly lower than males on four scales: appearance of the face, appearance distress, social function, and psychological function. CONCLUSION: These findings suggested that, when treating patients with oligodontia, the number of agenetic teeth, age, and gender should be taken into account. These factors could have negative effects on their self-assessment of appearance, their facial function, and their quality of life. CLINICAL SIGNIFICANCE: The increased difficulty with eating and drinking associated with more agenetic teeth highlighted the importance of functional (re)habilitation.

People's Willingness to Pay for Dental Checkups and the Associated Individual Characteristics: A Nationwide Web-Based Survey among Japanese Adults.

This study aimed to determine the willingness-to-pay (WTP) values for dental checkups and analyze the association between the values and individual characteristics. This cross-sectional study was conducted using a nationwide web-based survey, and 3336 participants were allocated into groups that received regular dental checkups (RDC; n = 1785) and those who did not (non-RDC; n = 1551). There was a statistically significant difference in the WTP value for dental checkups between the RDC (median: 3000 yen [22.51 USD]) and non-RDC groups (2000 yen [15.01 USD]). In the RDC group, age 50-59 years, household income <2 million yen, homemaker and part-time worker employment status, and having children were significantly associated with decreased WTP values; male sex, household incomes ≥8 million yen, and tooth brushing ≥3 times daily were associated with increased WTP values. In the non-RDC group, age ≥30 years, household incomes <4 million yen, and having ≥28 teeth were significantly associated with decreased WTP values; household income ≥8 million yen was associated with increased WTP values. Conclusively, WTP values for dental checkups were lower in the non-RDC group than in the RDC group; in the non-RDC group, those with lower household income aged ≥30 years were more likely to propose lower WTP values, suggesting the need for policy intervention to improve access to RDC.

Assessment of permanent teeth development in children with multiple persistent primary teeth.

BACKGROUND: Persistent primary teeth (PPT) may occur due to various local factors, or it may develop due to general factors such as systemic diseases and syndromes. Since eruption and dental development are two different processes, it is important to investigate both processes to determine the actual cause of delayed tooth eruption. The study aimed to evaluate the dental development of a group of Turkish children with multiple PPT using the Willems dental age estimation method. STUDY DESIGN: Digital panoramic radiographs of children and adolescents aged between 9 and 15 years were retrieved, assessed and categorized. A total of 80 radiographs of patients with more than one PPT were selected and matched with children without PPT. Dental age was calculated using the method of Willems et al. All analyses were conducted using the SPSS statistical software. The statistical significance was set at 0.05. RESULTS: The permanent tooth development of children with multiple PPT could be delayed by 0.5-4 years compared to healthy ones. A strong positive correlation was found between the number of PPT and deviation for both females and males (p < 0.001). CONCLUSION: In conclusion, we found that permanent tooth development of children with multiple PPT could be delayed compared to healthy ones. In addition, as the number of PPT increased, the difference between chronological age and dental age also increased, especially in males.