Molar hypomineralization: What is the US experience?

Dietary and metabolic effects on the oral status of patients with phenylketonuria: a nation-based cross-sectional study

OBJECTIVES

The aim of this study was to compare the prevalence of oral diseases (caries, periodontal disease, enamel defects) between patients with phenylketonuria (PKU), their siblings, and a matched control group.

MATERIALS AND METHODS

A total of 109 patients with PKU, 14 siblings of PKU patients, and 100 healthy individuals aged 6 to 68 years were recruited. All participants completed a questionnaire based on their health status. The patients' decayed/missing/filled teeth index (dmft/DMFT), gingival bleeding index (GBI), plaque control record (PCR), periodontal screening and recording index (PSR), and developmental enamel defects index (DDE) were recorded. Descriptive statistics and regression modeling were used to examine potential associations between the exposure and the outcomes of interest.

RESULTS

Patients with PKU had 1.6 times more caries (95% confidence interval (CI) 1.22 to 2.20; p = 0.001), seven times more enamel defects (95% CI 3.94 to 14.21; p < 0.001), and four times higher PSR values (95% CI 2.26 to 7.15; p < 0.001) than the control group. The siblings had significantly fewer enamel defects but no significant differences in caries and periodontal parameters compared to the PKU patients.

CONCLUSIONS

The results showed a higher risk for the development of caries, periodontitis, and enamel defects in PKU patients.

CLINICAL RELEVANCE

Implementation of preventive measures and regular dental care is necessary for patients with PKU.

Fracture resistance of prefabricated versus custom-made zirconia crowns after thermo-mechanical aging: an in-vitro study

BACKGROUND

Prefabricated zirconia crowns for a young permanent molar is a child-friendly solution for restoring a permanent molar at a young age. This in-vitro study aimed to compare the fracture resistance of prefabricated versus custom-made permanent molar crowns.

METHODS

16 identical resin dies were fabricated to receive permanent molar zirconia crowns, dies were divided into 2 groups, 1) received perfricated crowns, 2) custom-made crowns. Thermo-dynamic cycling was performed to simulate 6 months in the oral cavity, Fracture resistance of each group was assessed by applying increasing load till fracture. Data were tested for normality using Shapiro-Wilk and Levene's tests. Data were analyzed using independent t test.

RESULTS

No statistically significant difference was found between fracture resistance of prefabricated and custom-made crowns (1793.54 ± 423.82) and (1987.38 ± 414.88) respectively. 3 crowns of the custom-made group fractured with the underlying die, versus zero dies fractured in the prefabricated group.

CONCLUSIONS

Prefabricated permanent molars zirconia crowns can perform as well as custom-made crowns for an adult in terms of fracture resistance, it is suitable for children and can withstand the occlusal forces of an adult.

Management of compromised first permanent molars in a cohort of UK paediatric patients referred to hospital-based services

BACKGROUND

There are diverse opinions among dentists about managing compromised first permanent molars (cFPMs) in children and a perceived lack of guidance to help them evaluate prognosis.

AIM

To evaluate the current management of cFPM in children referred to a UK hospital centre and to report the severity of the affected teeth.

DESIGN

A service evaluation was undertaken, based on case records of medically fit children (6-11 years) referred to for the management of cFPMs. The presence of hypomineralisation, post-eruptive breakdown and the proposed care plans were recorded. Radiographic signs of severity were scored using the ICDAS index (intra/inter-rater kappa 0.96/0.82).

RESULTS

From 349 records screened over a 4-month period, 249 met the selection criteria. Almost 81% were planned to have extraction of at least one cFPM, whereas 19.3% were managed without extraction. More than half of the extraction cases (n = 105) had radiographic radiolucencies not exceeding the middle third of dentine in the worst-affected FPM. At the time of extraction, the mean age of the patients was 9.8 years (±0.9). GA was used in 196 (97.5%) cases, and 40.8% had not received previous treatment in any of their cFPMs.

CONCLUSION

Potentially restorable cFPMs in children is, most of the time, in a cohort of UK patients referred for tier 3 services, being managed by timed extractions under general anasethesia.

The quality and readability of online molar incisor hypomineralisation patient education materials: a systematic analysis

Background

Molar incisor hypomineralization (MIH) is estimated to affect 14% of children worldwide. It is crucial that patients and their families have access to easily comprehensible and reliable MIH‐relevant information. This study aims to determine the quality, reliability and readability of online patient education materials about MIH.

Methods

A systematic search strategy was adopted. Five validated tools were used to assess the content of the 21 websites that satisfied inclusion/exclusion criteria. Data analyses were applied via GraphPad Prism software version 9 (GraphPad Software, San Diego, CA, USA).

Results

Five (23.8%) websites only satisfied the criteria for understandability and two (9.5%) websites satisfied the criteria for actionability using the Patient Education Materials Assessment Tool (PEMAT). No website contained the Health on the Net (HON)Code Seal and the mean (SD) Journal of theAmerican Medical Association number of benchmarks per website was 1.33/4 (1.02). All websites failed to reach recommended minimum readability levels. Higher PEMAT scores were associated with ‘easier’ readability.

Conclusions

Online patient education materials related to MIH are lacking in quality and reliability, and are too difficult for most to read easily. The authors of MIH‐related online content should consider reference to quality of information tools when developing patient education materials.

A Breakthrough in Understanding the Pathogenesis of Molar Hypomineralisation: The Mineralisation-Poisoning Model

Popularly known as "chalky teeth", molar hypomineralisation (MH) affects over 1-in-5 children worldwide, triggering massive amounts of suffering from toothache and rapid decay. MH stems from childhood illness and so offers a medical-prevention avenue for improving oral and paediatric health. With a cross-sector translational research and education network (The D3 Group; thed3group.org) now highlighting this global health opportunity, aetiological understanding is urgently needed to enable better awareness, management and eventual prevention of MH. Causation and pathogenesis of "chalky enamel spots" (i.e., demarcated opacities, the defining pathology of MH) remain unclear despite 100 years of investigation. However, recent biochemical studies provided a pathomechanistic breakthrough by explaining several hallmarks of chalky opacities for the first time. This article outlines these findings in context of previous understanding and provides a working model for future investigations. The proposed pathomechanism, termed "mineralisation poisoning", involves localised exposure of immature enamel to serum albumin. Albumin binds to enamel-mineral crystals and blocks their growth, leading to chalky opacities with distinct borders. Being centred on extracellular fluid rather than enamel-forming cells as held by dogma, this localising pathomechanism invokes a new type of connection with childhood illness. These advances open a novel direction for research into pathogenesis and causation of MH, and offer prospects for better clinical management. Future research will require wide-ranging inputs that ideally should be coordinated through a worldwide translational network. We hope this breakthrough will ultimately lead to medical prevention of MH, prompting global health benefits including major reductions in childhood tooth decay.

Management of Patients with Poor Prognosis First Permanent Molars Beyond 'Ideal' Timing

The management of compromised first permanent molars is a common clinical conundrum in paediatric dentistry. Extensive guidance exists which supports the timed extraction of severely affected molars presenting at 8-10 years to allow favourable eruption of unaffected second permanent molars. However, treatment planning becomes more of a challenge when this window of opportunity is missed. In these situations, we are left with a tooth of guarded long-term prognosis in a patient where access and cooperation can be challenging. Delays to routine care as a result of the COVID-19 pandemic are likely to make this a more common clinical presentation so this article aims to discuss management options for these patients.

Cross-sectional analysis of dental treatment under general anaesthesia in hospitalised Western Australian children in 2018-19

Objective To date, there has been little research that has comprehensively analysed dental treatment under general anaesthesia (DGA) at Perth Children's Hospital (PCH) for dental emergencies (dental pain and sepsis). This cross-sectional descriptive analysis of the PCH dental department analysed the demographic of children admitted and the type of treatment used, and assessed the cost. Methods This was a retrospective descriptive study analysing the dental records of patients ranging from 2 to 16 years of age at PCH in Western Australia. Of the 310 cases randomly selected from the 2018-19 study period, 202 were admitted for DGA. Two outcome measures were derived: cumulative count of treatment mix and cost analysis. Results The mean (±s.d.) age at the time of admission was 6.2±2.6 years and the mean (±s.d.) decayed (d/D), missing, (m/M) and filled (f/F) teeth (dmft/DMFT) was 2.1±0.8. Of the 429 teeth affected, 282 were molars. Treatments were grouped therapeutically; of the 856 treatments performed, 465 were extractions (54%). The total cost, consisting of direct and indirect costs, was A$313823, and equated to an approximate mean (±s.d.) of A$1554±109 per case. Conclusion Untreated dental caries was the most common cause for hospital admission. Most cases presenting at the emergency department were young children (<7 years old) who underwent extractions under DGA. What is known about the topic? The Child Dental Benefits Schedule (CDBS) was introduced to improve access and affordability to oral health care for children without private dental insurance. However, a significant number of children are still being admitted to hospital for emergency dental treatment. What does this paper add? Despite the availability of the CDBS, untreated dental caries remains one of the most common reasons for dental emergency in the PCH. What are the implications for practitioners? Not only are direct costs a burden on the health budget, but indirect and intangible costs also affect children and their families.

Molar and Incisor Hypomineralization

Molar and incisor hypomineralization is a developmental defect that is systemic in origin that affects one or more than one permanent first molars, and is often associated with permanent incisors. It is usually characterized by well demarcated opacities and qualitative enamel defects caused by decreased inorganic enamel components, and reduced mineralization. It can cause esthetic, functional, psychological, and behavioral problems in children. Its reported prevalence varies widely, from 2.5% to 40.2%. Multiple aspects of dental treatment for it are challenging, such as behavior management, difficulty in achieving adequate local anesthesia, tooth hypersensitivity, and retention of restorations. This review discusses the most important considerations pertaining to its prevalence, severity, etiology, differential diagnosis, and some of the challenges and treatment modalities applicable in young patients. Data is collected from PubMed, Medline, and Embase databases.

100 Years of Chalky Teeth Research: From Pioneering Histopathology to Social Good

One hundred years ago, histopathology pioneer Bernhard Gottlieb described developmentally disrupted teeth as having “chalky enamel” and “chalky spots” that “crumble” easily. He also asked pivotal questions about the pathogenesis of “enamel hypoplasia” that remained enigmatic for almost a century. Today, breakthrough pathomechanistic investigations of chalky enamel are revealing surprising answers, and an allied translational initiative—The D3 Group for developmental dental defects (“D3s”) —is converting such scientific knowledge into social good surrounding prevention of tooth decay. Molar hypomineralisation (MH) affects 1-in-5 children worldwide and is well-evidenced, but poorly recognised, as a principal risk factor for childhood tooth decay. Given MH is causally linked to infantile illness, an exciting corollary is that medical prevention would lead to substantial reductions in decay. Here we reflect on the past century of chalky teeth research and retrace the path leading to recognition of MH as a global health concern. Five research eras, today's four major D3s, and diverse experimental attacks are outlined alongside translational wins that have benefitted global health. Addressing hopes for medical prevention of MH, this centennial year's pathomechanistic discovery is contextualised against past accomplishments and new opportunities. Finally, we note the translational value of accessible infographics for guiding future work, and forecast exciting prospects for the next century.

Pathogenesis of Molar Hypomineralisation: Aged Albumin Demarcates Chalky Regions of Hypomineralised Enamel

Molar hypomineralisation (MH) is becoming globally recognised as a significant public health problem linked to childhood tooth decay. However, with causation and pathogenesis unclear after 100 years of investigation, better pathological understanding is needed if MH is to become preventable. Our studies have implicated serum albumin in an extracellular pathomechanism for chalky enamel, opposing longheld dogma about systemic injury to enamel-forming cells. Hypothesising that chalky enamel arises through developmental exposure to serum albumin, this study used biochemical approaches to characterise demarcated opacities from 6-year molars. Addressing contradictory literature, normal enamel was found to completely lack albumin subject to removal of surface contamination. Querying surface permeability, intact opacities were found to lack salivary amylase, indicating that “enamel albumin” had become entrapped before tooth eruption. Thirdly, comparative profiling of chalky and hard-white enamel supported a dose-response relationship between albumin and clinical hardness of opacities. Moreover, albumin abundance delineated chalky enamel from white transitional enamel at opacity borders. Finally, addressing the corollary that enamel albumin had been entrapped for several years, clear signs of molecular ageing (oxidative aggregation and fragmentation) were identified. By establishing aged albumin as a biomarker for chalky enamel, these findings hold methodological, clinical, and aetiological significance. Foremost, direct inhibition of enamel-crystal growth by albumin (here termed “mineralisation poisoning”) at last provides a cogent explanation for the clinical presentation of demarcated opacities. Together, these findings justify pursuit of an extracellular paradigm for the pathogenesis of MH and offer exciting new prospects for alleviating childhood tooth decay through medical prevention of MH.

Tooth Enamel and its Dynamic Protein Matrix

Tooth enamel is the outer covering of tooth crowns, the hardest material in the mammalian body, yet fracture resistant. The extremely high content of 95 wt% calcium phosphate in healthy adult teeth is achieved through mineralization of a proteinaceous matrix that changes in abundance and composition. Enamel-specific proteins and proteases are known to be critical for proper enamel formation. Recent proteomics analyses revealed many other proteins with their roles in enamel formation yet to be unraveled. Although the exact protein composition of healthy tooth enamel is still unknown, it is apparent that compromised enamel deviates in amount and composition of its organic material. Why these differences affect both the mineralization process before tooth eruption and the properties of erupted teeth will become apparent as proteomics protocols are adjusted to the variability between species, tooth size, sample size and ephemeral organic content of forming teeth. This review summarizes the current knowledge and published proteomics data of healthy and diseased tooth enamel, including advancements in forensic applications and disease models in animals. A summary and discussion of the status quo highlights how recent proteomics findings advance our understating of the complexity and temporal changes of extracellular matrix composition during tooth enamel formation.

Pathogenesis of Molar Hypomineralisation: Hypomineralised 6-Year Molars Contain Traces of Fetal Serum Albumin

Molar Hypomineralisation (MH) is gaining cross-sector attention as a global health problem, making deeper enquiry into its prevention a research priority. However, causation and pathogenesis of MH remain unclear despite 100 years of investigation into “chalky” dental enamel. Contradicting aetiological dogma involving disrupted enamel-forming cells (ameloblasts), our earlier biochemical analysis of chalky enamel opacities implicated extracellular serum albumin in enamel hypomineralisation. This study sought evidence that the albumin found in chalky enamel reflected causal events during enamel development rather than later association with pre-existing enamel porosity. Hypothesising that blood-derived albumin infiltrates immature enamel and directly blocks its hardening, we developed a “molecular timestamping” method that quantifies the adult and fetal isoforms of serum albumin ratiometrically. Applying this novel approach to 6-year molars, both isoforms of albumin were detectable in 6 of 8 chalky opacities examined (corresponding to 4 of 5 cases), indicating developmental acquisition during early infancy. Addressing protein survival, in vitro analysis showed that, like adult albumin, the fetal isoform (alpha-fetoprotein) bound hydroxyapatite avidly and was resistant to kallikrein-4, the pivotal protease involved in enamel hardening. These results shift primary attention from ameloblast injury and indicate instead that an extracellular mechanism involving localised exposure of immature enamel to serum albumin constitutes the crux of MH pathogenesis. Together, our pathomechanistic findings plus the biomarker approach for onset timing open a new direction for aetiological investigations into the medical prevention of MH.

Are the Internet users concerned about molar incisor hypomineralization? An infoveillance study

BACKGROUND

Molar incisor hypomineralization (MIH) is a developmental enamel defect characterized by well-demarcated discolorations frequently detected in molars, causing pain and esthetic alterations.

AIM

To assess the interests of Google users on MIH-related information.

DESIGN

Digital data were collected in Google Trends through two search strategies, 'molar incisor hypomineralization' (topic) and 'MIH' (search term), between January 2004 and November 2018. ARIMA models were applied to analyze trends of curves and to predict the activity of Google users during 12 months. Autocorrelation and partial autocorrelation (ACF/PACF) plots were used to detect trends in the variation of relative search volume (RSV) related to search strategies over time. The most popular queries were analyzed qualitatively, whereas geographical heat maps were retrieved to determine search volumes according to countries (P < .05).

RESULTS

Gradual increasing trends were detected, with forecasts indicating similar levels of RSVs to the period between December 2017 and November 2018. Most popular queries and topics were associated with MIH diagnosis, being retrieved predominantly in European countries.

CONCLUSIONS

The activity of Google users related to this condition is maintained low, with a reduced intensification over time, suggesting that the awareness on MIH is probably confined to dentists and affected people worldwide.

Molar incisor hypomineralisation (MIH) - an overview

Recent data indicates that molar-incisor hypomineralisation (MIH) is a frequently - encountered dental condition worldwide. The condition could be associated with dental complications that might affect patients' quality of life as well as create treatment challenges to dentists. The affected teeth are more prone to caries and post-eruptive enamel breakdown, therefore, it is believed that this condition might be responsible for a substantial proportion of childhood caries since the condition has high prevalence. MIH is common, and as such it should be diagnosed and managed in primary care wherever possible. Early diagnosis can lead to more effective and conservative management. This article aims to highlight different aspects related to MIH, from its prevalence to treatment options in young patients.