Developmental Defects of Enamel.

Amelogenesis, the intricate process governing enamel formation, is susceptible to a range of genetic, systemic, and environmental influences, resulting in distinct developmental defects of enamel (DDE), such as molar incisor hypomineralisation (MIH), enamel hypoplasia, dental fluorosis, and amelogenesis imperfecta (AI). This chapter aims to provide a comprehensive overview of amelogenesis and DDE, establishing correlations between histopathological findings and clinical manifestations. MIH, a qualitative enamel defect, occurs during the mineralisation and maturation phases, affecting first permanent molars and eventually incisors. Diagnostic challenges in MIH arise from the disorder's unique features, including variable tooth involvement and severity, influenced by a complex interplay of genetic, systemic, and environmental factors. Enamel hypoplasia, a quantitative defect, manifests in any tooth during enamel matrix secretion. Etiological factors include local, systemic, environmental, and genetic influences, with variable enamel matrix abnormalities depending on the stage of amelogenesis when aggression occurred. Dental fluorosis, a toxicological concern from chronic and excessive fluoride exposure, affects ameloblasts and compromises crystal growth of the homologous teeth during enamel development. Lastly, AI, an inherited condition, encompasses diverse phenotypes in enamel development. AI phenotypes, whether hypoplastic or hypomineralised, entail mutations in genes, such as AMELX, ENAM, MMP20, KLK4, WDR72, FAM83H, C4ORF26, amelotin, GPR68, and ACPT. Diagnosing AI involves considering family history and clinical observation. In conclusion, navigating the intricacies of amelogenesis, from MIH to AI, underscores the critical importance of accurate diagnosis for proper clinical management of DDE.

MIH-Affected Substrate: An Overview of Adhesive Challenges to the Dental Structures.

Based on the current state of the art regarding molar incisor hypomineralisation (MIH)-affected enamel, bonding systems are expected to play a relevant role on the restorative procedures when required. MIH-affected enamel is often subjected to posteruptive breakdown combined or not with carious lesions, predominantly on molars, and may also affect the aesthetics of anterior teeth. As unbalanced mineral and protein contents occur, understanding these alterations is essential before selecting the most appropriate adhesive systems, while bearing in mind their limitations. In particular, when dentin is involved due to enamel breakdown, the use of functional monomer-based bonding systems present in self-etching and universal systems produce a chemical interaction that enhance the bonding. So far, the overall recommendation relies on placing the margin of the restoration on clinically sound enamel, regardless of the category of the adhesive system.

Implications of Histological and Ultrastructural Characteristics on the Chemical and Mechanical Properties of Hypomineralised Enamel and Clinical Consequences.

Molar incisor hypomineralisation (MIH) is a qualitative type of enamel defect, which occurs due to a failure in the biomineralisation process of the enamel organic matrix during amelogenesis. The tooth enamel affected by MIH shows changes in its chemical, structural, and mechanical properties, leading to different clinical repercussions. The color of MIH opacities varies from opaque white to yellow/brown, and elemental analyses of these lesions show a lower calcium and phosphate content, minerals that are more abundant in sound enamel. Furthermore, the incorporation of other molecules occurs, such as carbonate, a component that provides a greater degree of solubility, thus making hypomineralised enamel more susceptible to posteruptive fractures. At a structural level, the layer of hydroxyapatite crystals appears to be disorganized, with morphological changes, implying a greater degree of porosity in the structure. The increase in porosity of the structure may be associated with dental hypersensitivity, a common clinical repercussion among patients with MIH. Among the mechanical properties, a decrease in hardness and modulus of elasticity occurs, and this also makes the enamel more fragile. Deficiency in biomineralisation can be caused by changes in the function of ameloblasts or by failures at the intercellular junction that result in lower activity of proteases such as MMP-20 and KLK4. The increase in proteins in the organic matrix of enamel impairs the growth and incorporation of minerals into the hydroxyapatite crystals, so that the enamel becomes hypomineralised and has larger organic content, thus having an impact on its properties. These changes present in the enamel with MIH help to explain the clinical repercussions caused by this condition.

Understanding the Enamel Disintegration and Posteruptive Breakdown of Demarcated Opacities on Molar Incisor Hypomineralisation.

This review aims to present scientific knowledge regarding the demarcated opacities of molar incisor hypomineralisation (MIH) and factors that clarify the occurrence of posteruptive enamel breakdown. The demarcated opacities have distinct boundaries with the adjacent nonaffected enamel and may vary in color among white, creamy, yellow, and brownish. The hypomineralised enamel is more porous and less organized than the nonaffected enamel. As a result of the reduced mineral content and higher protein content, the hypomineralised enamel shows a progressive reduction in its mechanical properties according to the opacity feature. Chemically, the protein content of MIH opacities is abnormally high, mainly composed by albumin, which is a serum protein usually not found in mature enamel. The highest protein content is seen in brown opacities, followed by yellow and white opacities, both with higher protein content than nonaffected enamel. The fact that the hypomineralised enamel is more fragile than the nonaffected enamel is supported not only by laboratorial findings but also by clinical prospective studies that observed an aggravation of MIH over time, as well as the correlation between the color of the demarcated opacities and the risk of posteruptive enamel breakdown. A better understanding about the microstructure of the hypomineralised enamel has relevant implications for the clinical approach of the condition. In the clinic, besides a comprehensive assessment of anamnesis and clinical data, it is advisable to record the color and the location of the opacities by tooth surface in order to support the treatment decisions and estimate a prognosis for MIH patients.

Is It Possible to Remineralise Hypomineralised Enamel Lesions in Patients with Molar Incisor Hypomineralisation?

Molar incisor hypomineralisation (MIH) is characterized with reduced enamel mineral quantity, especially in the calcium and phosphate content, with increases in the carbonate and protein contents. Albumin is the main protein that accumulates pre-eruptively, leading to defective initiation of mineralisation. Other oral-fluid proteins are found in cases of posteruptive enamel surface breakdown. Most of the lesions extend through the full thickness of enamel. Due to the lower mineral quantity and increased carbon and protein content, MIH teeth are more prone to fractures once exposed to mastication. In addition, susceptibility to dental caries is increased and hypersensitivity is common in MIH patients. For these reasons, MIH-affected teeth might benefit from exposure to remineralising agents that will decrease caries susceptibility and reduce sensitivity. Several in vitro, in situ, and in vivo studies have shown that improving the mineralisation of MIH teeth after eruption is possible, especially at the surface. However, complete resolution is difficult due to the depth/thickness of these lesions. In fact, the process is similar to posteruptive maturation. Thus, this nomenclature should be used instead of remineralisation. The evidence available so far indicates that among the several available remineralising agents, casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) cream and fluoride (F) varnish show the best results and are equally effective in remineralising MIH-affected teeth. Fluoride varnish demands no patient adherence, while CPP-ACP cream can be applied at home. However, it is important to consider that fluoride varnish is generally more economical than CPP-ACP cream. Consequently, the choice between these agents can be tailored to the patient's specific requirements.

Dual-species biofilm of Streptococcus mutans and Candida albicans produces subsurface caries lesions on bovine enamel.

OBJECTIVES: To develop a protocol for forming subsurface caries lesions on bovine enamel by dual-species biofilms of Streptococcus mutans and Candida albicans in vitro. DESIGN: Biofilms were grown on bovine enamel specimens in artificial saliva (AS) for seven days. After 24 h of formation, the AS was supplemented or not with fluoride (F) using sodium fluoride (0.005 or 0.008 ppm F), and the biofilms were exposed or not to a 20 % sucrose solution (reproducing a cariogenic challenge) once/day. On the seventh day, the biofilms were harvested and had their extracellular polysaccharides (EPS) and inorganic components analyzed. The specimens were subjected to computed X-ray microtomography analysis to determine their mineral concentration. Data were compared using two-way analyses of variance, followed by Fisher's LSD or Student-Newman-Keuls tests (p < 0.05). RESULTS: Biofilms exposed to the cariogenic challenge had significantly higher EPS concentrations than those not exposed, regardless of the presence of F. For biofilms grown with 0.008 ppm F, those exposed to the cariogenic challenge had lower F levels than those not exposed. For biofilms exposed to the cariogenic challenge, those grown with 0.008 ppm F had lower lesion depths and integrated mineral loss, and higher outer layers than those grown without F. CONCLUSIONS: The dual biofilm model assessed was able to create subsurface caries lesions in bovine enamel in vitro, which was influenced by the presence of F in the culture medium and exposure to sucrose.

Clinical, Radiographic, and Histological Changes in Enamel and Dentin, According to Caries Care International™ Evaluation, In Permanent Posterior Teeth: An Observational Study / Cambios Clínicos, Radiográficos e Histológicos en Esmalte y Dentina, Según Evaluación de Caries Care International™, en Dientes Posteriores Permanentes: Un Estudio Observacional

SUMMARY: CariesCare International ™ practical guide is a tool for the comprehensive assessment and treatment of caries that synthesizes clinical and radiographic diagnosis and risk factors, classifying the severity, progression, and activity of lesions. The objective of this study was to analyze the validity and prediction characteristics of the proposed dental caries classification in the CariesCare International ™ practical guide as a reference through clinical and radiographic evaluation versus histological evaluation. Ninety-seven permanent posterior teeth were evaluated, and clinical and radiographic diagnoses were determined according to parameters defined in the CariesCare International™ guide as a reference. Subsequently, histological evaluation was performed to compare each stage of dental caries progression, and statistical analysis was applied. When comparing the validity and prediction values between radiographic and clinical diagnoses in relation to histological evaluation, a low sensitivity and high specificity relationship was found. The sensitivity and specificity percentages between the clinical and radiographic methods show that the clinical method has a lower number of false negatives. Histological changes in dental tissue were evident from the earliest stages of lesions, even in those not related to the caries process, indicating that the dentist should be careful when deciding on a treatment plan and take into account all variables involved in the caries process, as proposed by the CariesCare International ™ guide.

La guía práctica CariesCare International™ es una herramienta para la evaluación y tratamiento integral de la caries que sintetiza el diagnóstico clínico y radiográfico y los factores de riesgo, clasificando la gravedad, progresión y actividad de las lesiones. El objetivo de este estudio fue analizar la validez y características de predicción de la clasificación de caries dental propuesta en la guía práctica CariesCare International™ como referencia a través de la evaluación clínica y radiográfica versus la evaluación histológica. Se evaluaron noventa y siete dientes posteriores permanentes y se determinaron diagnósticos clínicos y radiográficos según parámetros definidos en la guía CariesCare International™ como referencia. Posteriormente se realizó una evaluación histológica para comparar cada etapa de progresión de la caries dental y se aplicó análisis estadístico. Al comparar los valores de validez y predicción entre los diagnósticos radiológicos y clínicos en relación con la evaluación histológica, se encontró una relación de baja sensibilidad y alta especificidad. Los porcentajes de sensibilidad y especificidad entre el método clínico y radiográfico muestran que el método clínico tiene un menor número de falsos negativos. Los cambios histológicos en el tejido dental fueron evidentes desde las primeras etapas de las lesiones, incluso en aquellas no relacionadas con el proceso de caries, lo que indica que el odontólogo debe tener cuidado al decidir un plan de tratamiento y tener en cuenta todas las variables involucradas en el proceso de caries, tal como propone la guía CariesCare International™.

Enamel Caries Lesion Depth Obtained by Optical Coherence Tomography and Transverse Microradiography: A Comparative Study.

INTRODUCTION: Visual imaging of subsurface caries lesions is of vital interest in dentistry, which can be obtained by invasive radiography technique as well as by available non-destructive imaging approaches. Thus, as a first step toward the development of a new innovative approach, Spectral-domain optical coherence tomography (SD-OCT) was applied to detect the lesion depth in comparison to the established reference technique (transverse microradiography [TMR]). METHODS: Bovine enamel specimens were demineralized for 5 days, following previous studies. For OCT, the resulting artificial lesions were scanned three-dimensionally (SD-OCT) and semi-automated measured (CarLQuant). For TMR, specimens were sectioned and the lesion depth was manually determined (Inspektor Research System). RESULTS: The range of lesion depth detected with OCT was 24.0-174.0 µm (mouth rinse study), 18.0-178.0 µm (toothpastes study) and with TMR 59.2-198.0 µm (mouth rinse study), 33.2-133.4 µm (toothpastes study). We found a strong correlation between both methods in terms of lesion depth (Spearman rankwith outlierp < 0.001, Rho = 0.75, Spearman rankwithout outlierp = 0.001, Rho = 0.79). The two methods produce similar results (Passing-Bablok regression, 1.16). As deeper is the lesion, the smallest is the difference between both methods as indicated by Bland-Altman-plots. CONCLUSION: Especially in the case of deep lesions, the values obtained by both methods are in agreement, and OCT can potentially substitute TMR to detect and assess lesion depth with the benefit of being non-destructive.

Optical coherence tomography and gray scale digital analysis as noninvasive techniques for evaluating molar-incisor hypomineralization severity: A comparative study with microcomputed tomography.

Molar-incisor hypomineralization (MIH) is a qualitative defect of dental enamel characterized by demarcated opacities present in permanent first molars and other teeth. It is considered a major clinical challenge in dentistry because it makes affected teeth more susceptible to fractures and dental caries. Its diagnosis is mainly clinical and there are few technological resources that allow for a more accurate diagnosis, especially with respect to the depth of the defect in the dental enamel. In this context, optical coherence tomography (OCT), which is routinely used in ophthalmology, can produce images of the depth of the dental enamel, making it a promising method. In this study, 33 teeth with different MIH severities were evaluated using OCT and microcomputed tomography (microCT). Semi-quantitative methods of grayscale pattern analysis were used to compare images obtained from different severities of MIH with the mineral density obtained through microCT. MicroCT evaluation revealed that hypomineralized enamel had a significantly lower mineral density than intact enamel. However, this difference was not observed between the mild and severe MIH lesions. In the OCT evaluation, significant differences were observed between the intact and hypomineralized enamel, and the gray value comparison provided a method for quantitative differentiation between the two. This study suggests that OCT could be a useful adjunct to traditional diagnostic methods for MIH, offering a noninvasive approach to evaluate enamel defects. RESEARCH HIGHLIGHTS: Combining optical coherence tomography with grayscale digital analysis shows potential as a promising method for diagnosing molar-incisor hypomineralization and assessing its level of severity.

Susceptibility of fluorotic enamel to dental erosion-abrasion.

Dental hard tissue conditions can be of pre- or post-eruptive nature, such as enamel fluorosis and erosive tooth wear (ETW), respectively. Dental enamel fluorosis is caused by the chronic and excessive intake of fluoride during enamel development, leading to increased fluoride concentration and increased porosity. ETW has become a common clinical condition and often impairs dental function and aesthetics. This in vitro study tested the hypothesis that fluorotic enamel presents different susceptibility to dental erosion-abrasion. It consisted of a 3×3×2 factorial design, considering a) fluorosis severity: sound (TF0), mild (TF1-2), moderate (TF3-4); b) abrasive challenge: low, medium, and high; and c) erosive challenge: yes or no. A total of 144 human teeth were selected according to the three fluorosis severity levels (n=48), and subdivided into six groups (n = 8) generated by the association of the different erosive and abrasive challenges. Enamel blocks (4×4 mm) were prepared from each tooth and their natural enamel surfaces subjected to an erosion-abrasion cycling model. After cycling, the depth of the lesions in enamel was assessed by profilometry. ANOVA showed that the three-way and two-way interactions among the factors were not significant (p > 0.20). Enamel fluorosis level (p=0.638) and abrasion level (p = 0.390) had no significant effect on lesion depth. Acid exposure caused significantly more enamel surface loss than water (p < 0.001). Considering the limitations of this in vitro study, fluorosis did not affect the susceptibility of enamel to dental erosion-abrasion.

Effectiveness of non-operative approaches in active enamel carious lesions: a retrospective longitudinal study.

The aim of the study was to investigate the effectiveness of non-invasive and micro-invasive treatments in active enamel carious lesions in high-caries-risk children. Clinical records of children treated in a dental school setting were retrospectively screened for active enamel carious lesions treated non-invasively (topical fluoride applications, oral hygiene instruction, or dietary guidance) or micro-invasively (sealant). The control of active carious lesions was set as the main outcome established by the combination of inactivation and non-progression of the lesions based on Nyvad and ICDAS criteria, respectively. Individual and clinical factors associated with the outcome were analyzed by Poisson regression. The sample consisted of 105 high-caries-risk children with a mean age of 8.3 (± 2.4) years. From a total of 365 active enamel carious lesions, most lesions (84.1%) were active non-cavitated carious lesions (ICDAS scores 1 and 2) and only 15.9% presented localized enamel breakdown (ICDAS score 3). Of these, 72.6% were inactivated and 92.1% did not progress (mean time of 6.5 ± 4.1 months). The prevalence of controlled carious lesions was higher among children older than 6 years (PR:1.43; 95%CI:1.00-2.03; p = 0.04) and in those with better biofilm control (PR:0.99; 95%CI: 0.98-0.99; p = 0.03). Non-operative approaches are effective for controlling active enamel carious lesions. The majority of active enamel carious lesions became inactive and did not progress after treatment. Caries control was associated with older children and better biofilm control.

Organic volume and permeability variations in the surface layer of artificial and natural enamel carious lesions.

OBJECTIVES: Test the hypothesis the type of enamel caries (natural, artificial induced by gel, and artificial induced by acid solutions) affect the organic volume and the permeability of the surface layer in enamel caries lesions. DESIGN: Artificial enamel caries, induced by either acidic solution (organic-poor; Group 1) or acidic gel (organic-rich; Group 2), and natural non-cavitated inactive approximal enamel caries lesions (NEC; Group 3) were obtained, from which longitudinal ground sections were prepared. Measurements of the mineral (Vmin) (by microradiography), and water (α) and organic (ß) volumes (by optical birefringence) were obtained at three points in the surface layer (n = 30/group). RESULTS: The main outcomes were the ratio between experimental ß by predicted ß (ß Ratio) and the ratio between experimental and predicted permeabilities (αd Ratio). ß Ratio in Group 1 was lower than in Groups 2 (Cohen's d: -1.81; 95% CI:-1.45,-2.32; p < 0.001) and 3 (Cohen's d: -0.71; 95% CI:-0.27,-1.18; p = 0.004), and Group 2 surpassed Group 3 (Cohen's d: 0.49; 95% CI:0.07,0.94; p = 0.03). αd Ratio in Group 1 was higher than in Groups 2 (Cohen's d: 1.86; 95% CI:1.49,2.33; p < 0.001) and 3 (Cohen's d: 0.60; 95% CI:0.18,1.14; p = 0.01), and Group 3 surpassed Group 2 (Cohen's d: 0.61; 95% CI:0.23,1.07; p = 0.01). CONCLUSIONS: The highest organic volume and the lowest permeability occurred at the surface layer of gel-induced artificial enamel caries lesions, which should be preferred in in vitro studies on de- and remineralization and resin infiltration.

New Theory Illustrates the Formation of Enamel CUP-Shaped Lesions on Occlusal Surfaces.

We propose a new theory for enamel cupping lesions formation. At early stages, naturally formed cupping lesions showed increased porosity at two structural prismatic traits: the central cone extending into the enamel-dentine junction and the type-I Hunther-Schreger bands (HSB), suggesting them to be the main drivers for cupping lesion formation and development. In addition, these lesions were circumscribed by type-II HSBs, which present lower surface porosity and higher resistance to wear. This theory was verified in in vitro observations, where both the central cone and the type-I HSB of cuspal enamel showed higher susceptibility to wear, potentially elucidating the mechanisms involved on cupping lesion formation.

Effectiveness of fluoride-containing toothpastes associated with different technologies to remineralize enamel after pH cycling: an in vitro study.

BACKGROUND: To evaluate the efficacy of fluoride-containing toothpastes with different technologies to remineralize artificial caries lesions in enamel. METHODS: Bovine enamel blocks were divided into three thirds: intact (untreated), demineralized (artificial caries lesion), and treated (caries lesion, pH cycling with dentifrices). Enamel blocks were randomly distributed into five groups (n = 12): Fluoride-free toothpaste, Colgate Oral Care (NC); Arginine-containing toothpaste, Colgate Total Daily Repair (PC); Silicate-based fluoride toothpaste: REFIX technology, regenerador + sensitive (RDC), NR-5 technology, Regenerate Enamel Science (RES), and NOVAMIN technology, Sensodyne Repair and Protect (SRP). The specimens were submitted to a pH cycling model for 6 days. The efficacy of the toothpastes was estimated by calculating the surface microhardness recovery (%SMHR) and the fluorescence recovery (ΔFRE) with quantitative light-induced fluorescence. The cross-sectional micromorphology of the enamel surface was also assessed using scanning electron microscopy. Elemental analyses (weight%) were determined with an energy-dispersive X-ray spectrometer (EDS). The results were compared to that of the control (NC). Data were statistically analyzed (5%). RESULTS: %SMHR could be ranked as follows: RDC = PC = RES = SRP > NC. Significantly higher %SMHR and ΔFRE means were observed after enamel treatment with RDC (22.7 and 46.9, respectively). PC (%SMHR = 18.8) was as efficacious as RDC to recover the surface microhardness with a significantly lower mean of ΔFRE (19.5). Only RDC was able to promote the formation of a mineralized layer on the surface of enamel enriched with silicon on the surface. CONCLUSIONS: The silicate-based fluoride toothpaste containing REFIX technology demonstrated greater efficacy in the remineralizing artificial caries than the other products.

Effect of a Toothpaste Containing Surface Pre-Reacted Glass-Ionomer Filler on the Remineralization of Artificial Carious Enamel Lesions in situ.

This study evaluated the remineralizing effect of a toothpaste containing surface pre-reacted glass-ionomer (S-PRG) filler on demineralized enamel in situ. For this, 180 bovine enamel samples were demineralized by using a microcosm biofilm model for 3 days. Thereafter, the samples were randomly signed to 15 healthy volunteers and to 3 cross-over in situ phases corresponding to the following treatments: (1) toothpaste containing 1,500 ppm F as NaMFP (positive control, Colgate®Cavity Protection), (2) toothpaste containing 5% S-PRG filler (Shofu®), and (3) placebo toothpaste (negative control prepared by Shofu®). Four demineralized enamel blocks were fixed into each palatal appliance per phase. The volunteers wore the appliances for 5 days and were trained to brush their teeth 2 times for 2 min a day, while one drop of the toothpaste's slurry (1:3) was dripped on each sample for the same period. The surface hardness and TMR analyses were done and analyzed by ANOVA/Tukey and t test (p < 0.05). S-PRG filler and Colgate® toothpastes were equally able to improve 2-2.5× enamel remineralization by the analysis of % surface hardness recovery. However, S-PRG toothpaste was the only one able to significantly improve ΔΔZ (the integrated mineral loss recovery: 1,489 ± 503 %vol.µm) compared to placebo (1,050 ± 467 %vol.µm), while Colgate® did not differ from placebo. No differences were seen between the groups with respect to ΔLD. S-PRG filler and Colgate® toothpastes show similar potential to remineralize the lesion surface. However, S-PRG toothpaste is better to recover mineral loss at the subsurface area.

Enamel Developmental Defect Masking on Central Incisor with Infiltrant Resin.

The aim of this paper is to present a case of masking of a hypoplastic lesion using the infiltrating resin technique, without use of drilling or any loss of tooth structure. A 22-year-old female patient complained of a noncarious white spot on the buccal surface of the upper right central incisor which affected the esthetics of her smile. Despite the tooth discoloration, the tooth structure was intact, with no depressions, cracks, or grooves. During the anamnesis, she reported that the white spot had been present since childhood. On the basis of the information provided by the patient and collected during intraoral clinical examination, it was determined that the stain was suggestive of enamel hypoplasia. The treatment proposed to the patient was the application of infiltrating resin to mask the hypoplasia on the surface of the tooth enamel without any loss of tooth structure. In this case, Icon infiltrating resin proved to be efficient in masking the hypoplastic lesion. The final appearance of the treated tooth was satisfactory, with homogeneity and gloss on the surface, which minimized the characteristics of an unpleasant smile.

Augmented Vision for Dental Students' Education in Detecting Proximal Carious Lesions on Bitewing Radiographs: A Randomized Controlled Trial.

This two-arm, parallel, randomized controlled trial aimed to assess the effect of augmented vision (AV, using interactive color overlays) on the education of dental students in detecting proximal carious lesions on bitewing radiographs compared to black-and-white textbook-like illustrations. Forty-eight preclinical third-year dental students were randomized using a random number generator into two learning groups: test (AV, allowing interaction with color-highlighted carious lesions, n = 24) and control (showing the native radiograph and a black-and-white illustration displaying the carious lesion, n = 24). First, students had 2 weeks to assess 50 bitewings (lesion prevalence on the tooth level: 54.5%) in the test or control. Due to the nature of the intervention, participants could not be blinded toward the intervention. After that, they were asked to detect lesions on 10 independent bitewings and to assess lesion extent (outer/inner enamel; outer/middle/inner dentin). The reference test was constituted by two experienced dentists. No significant differences in accuracy (test 0.84 [95% CI: 0.79, 0.88]; control 0.83 [0.78, 0.87]), AUC (test 0.82 [0.81, 0.84]; control 0.81 [0.80, 0.83]) and F1 score (test 0.79 [0.75, 0.82]; control 0.77 [0.72, 0.81]) were observed between groups. Students of both groups showed difficulties in differentiating enamel from dentin carious lesions. While AV was reported to be motivating by students, it did not increase their accuracy.

Detection of Cavitated Proximal Carious Lesions in Permanent Teeth: A Visual and Radiographic Assessment.

Detection of proximal carious lesions involves the combination of clinical and radiographic methods, both with inherent difficulties. The present cross-sectional study is aimed at estimating the prevalence of cavitation in proximal carious lesions, based on a direct clinical assessment of previously detected radiographic lesions, in permanent molars and premolars. Proximal dental surfaces were radiographically evaluated using the ADA coding system and cavitation was determined through clinical visual examination of the surfaces after separation with elastomeric bands. One-hundred and twenty-six patients attending the dental clinics at the University of Talca were examined, comprising 508 proximal surfaces with radiographic codes ranging from E1 to D3. Two examiners were trained and calibrated for radiographic and clinical detection of proximal lesions. Most participants were females (61.9%). The age mean of participants was 28.7 (0.8) years old. A total of 22.2% of the examined surfaces were cavitated. Only few lesions coded as E1 (n = 4; 2.1%) and E2 (n = 9; 9.8%) were cavitated. Fifty D1 (35.5%) and 22 D2 (41.5%) lesions were cavitated after separation. Most lesions coded as D3 (n = 28; 84.8%) were cavitated. The multilevel binary regression model (p = 0.003) demonstrated that sex, age, jaw, tooth type, surface, and side were not associated with the likelihood of having proximal cavitation. Challenging conventional wisdom, most D1 and D2 lesions were not cavitated. Combining detection methods seems desirable to increase the accuracy in assessing approximal posterior lesions. The low proportion of cavitated lesions reinforces the idea of cautiously indicating invasive approaches for managing proximal carious lesions.

Occlusal problems, mental health issues and non-carious cervical lesions.

Non-carious cervical lesions (NCCLs) are characterized by a loss of hard dental tissue near the cement-enamel junction with multifactorial etiology. The aim of this study was to demonstrate that occlusal factors as attrition, malocclusion, and bruxism, and mental disorders as depression, stress, and anxiety are involved in the etiology of NCCLs. Salivary samples and clinical data of 340 individuals selected from 6,112 participants were obtained from the University of Pittsburgh School of Dental Medicine Dental Registry and DNA Repository project. The affected group was formed by individuals with NCCL (34 females, 34 males, mean age 55.34 years). In addition, the comparison group was formed by individuals without NCCL (136 females, 136 males, mean age 55.14 years). Eleven single-nucleotide polymorphisms (SNPs) previously associated with mental disorders were genotyped and tested for association with NCCLs. When all occlusal factors were combined there was found a significant association with NCCL (p = 0.000001/adjusted OR 4.38, 95% CI 2.50-7.69). Attrition (OR 3.56, 95% CI 2.00-6.32) and malocclusion (OR 5.09, 95% CI 1.65-15.68) as separate variables showed statistically significant associations with NCCL. There was a significant difference in stress history between the two groups (OR 2.17, 95% CI 1.08-4.39). No associations between NCCLs and the SNPs selected were found. However, when the occlusal factors were analyzed as covariates, associations were found between bruxism and seven of the selected SNPs. Our results suggest that occlusal factors might be associated with NCCLs.

Enfoque de Tratamiento de una Adolescente con Amelogénesis Imperfecta / Treatment Approach for an Adolescent with Amelogenesis Imperfecta

La amelogénesis imperfecta (AI) es un grupo de tras-tornos hereditarios, clínica y etiológicamente hete-rogéneos, derivados de mutaciones genéticas, que se caracterizan por anomalías cualitativas y cuanti-tativas del desarrollo del esmalte, pudiendo afectar la dentición primaria y/o permanente. El tratamiento del paciente con AI es complejo y multidiscliplinario; supone un desafío para el odontólogo, ya que por lo general están involucradas todas las piezas dentarias y afecta no solo la salud buco dental sino el aspecto emocional y psicológico de los pacientes. Con el obje-tivo de describir el tratamiento integral y rehabilita-dor realizado en una paciente con diagnóstico de AI tipo III, se reporta el caso de un adolescente de sexo femenino de 13 años, que concurrió en demanda de atención a la Cátedra de Odontología Integral Niños de la Facultad de Odontología de la Universidad de Buenos Aires (FOUBA), cuyo motivo de consulta fue la apariencia estética y la hipersensibilidad de sus pie-zas dentarias. Durante el examen clínico intraoral, se observó que todas las piezas dentarias presentaban un esmalte rugoso, blando, con irregularidades y una coloración amarronada, compatible con diagnóstico de Amelogénesis Imperfecta tipo III hipomineralizada. Conclusión: El tratamiento rehabilitador de la AI en los pacientes en crecimiento y desarrollo estará diri-gido a intervenir de manera integral y temprana para resolver la apariencia estética y funcional, evitar las repercusiones sociales y emocionales, y acompañar a los pacientes y sus familias (AU)

Amelogenesis imperfecta (AI) is a group of clinically and etiologically heterogeneous hereditary disorders, derived from genetic mutations, characterized by qualitative and quantitative anomalies of enamel development, which can affect primary and/or permanent dentition. The treatment of patients with AI is complex and multidisciplinary, it is a challenge for the dentist, since in general all the teeth are involved and it affects not only oral health but also the emotional and psychological aspect of the patients. Objective: To describe the comprehensive and rehabilitative treatment carried out in an adolescent patient with a diagnosis of type III AI. Case report: The case of a 13-year-old female patient, who required dental attention at the Department of Dentistry for Children of the School of Dentistry of the University of Buenos Aires, whose reason for consultation was esthetic appearance and hypersensitivity of her teeth. In the intraoral clinical examination, it was observed that all the teeth had rough, soft enamel, with irregularities and a brownish color, compatible with the diagnosis of type III hypomineralized Amelogenesis Imperfecta. Conclusion: Rehabilitative treatment of AI in growing and developing patients will be aimed at early and comprehensive intervention to resolve esthetic and functional appearance, avoid social and emotional repercussions and accompany patients and their families (AU)