OBJECTIVE: In addition to molar incisor hypomineralisation, the occurrence of enamel hypomineralisation in the primary dentition has become increasingly important in recent years. Hypomineralised second primary molar (HSPM) is defined as hypomineralisation of systemic origin affecting from one to all four second primary molars. Some years ago, the \"Würzburg concept\" was introduced, which proposed a grading of MIH findings (MIH treatment need index) in combination with an appropriate treatment plan depending on the severity of the affected tooth. Recently, this concept was updated and new treatment approaches have been added. However, currently, the concept solely addresses the treatment plan for permanent teeth. As there is a need to expand its scope to encompass primary teeth and, consequently, HSPM, this paper seeks to develop the second component of the Würzburg concept, the treatment plan, for the primary dentition in response to the increased focus on the disease in recent years. Although the evidence base for the different treatment options is still weak, there is a need for guidance for clinicians in their day-to-day practice.
METHODS: The authors conducted a comprehensive review of the literature, encompassing clinical and laboratory studies along with published guidelines.
RESULTS: The treatment plan of the HSPM Würzburg concept contains prophylactic and regenerative aspects, non-invasive interventions, temporary and permanent restorative techniques, and extraction.
CONCLUSIONS: The intention is to provide practical guidance to practitioners, acknowledging the necessity for further validation through clinical trials.

OBJECTIVE: To evaluate clinical and radiographic outcomes of vital pulp therapy (VPT) in deeply carious young permanent first molars (PFM) affected with MIH over 24 months.
METHODS: In this prospective randomized clinical trial, n = 50 children with deeply carious young PFM affected with MIH, and diagnosed with reversible or irreversible pulpitis were randomized into 2 groups: indirect pulp treatment (IPT) and pulpotomy (partial or complete). Teeth were followed up clinically and radiographically for 24 months. Statistical analysis was done using Chi-square test; P ≤ 0.05 was considered significant.
RESULTS: A total of  n = 50 teeth/patients (n = 26 females (52%), n = 24 males (48%)) were included, and 14 upper and 36 lower PFM were treated. Mean age was 11 ± 3.2 years. Clinical and radiographic success rates were: 96% for IPT, 90% for PP and 82% for CP (and 86% for both types of pulpotomy combined) over 24 months. There were no significant differences in outcomes between treatment groups. Age, gender and tooth location/jaw were found to have no statistically significant difference in outcomes among treatment groups, nor did pulpal status or root maturity, regardless of type of VPT and follow up period.
CONCLUSIONS: VPT is a valid treatment option in deeply carious young permanent first molars affected with MIH over 24 months. IPT had a higher clinical and radiographic success rate (96%) than partial or cervical pulpotomy (total 86%), but the difference was not statistically significant. Future randomized clinical trials on VPT for teeth affected with MIH are recommended with larger sample size and longer follow-up.

OBJECTIVE: Hypersensitivity is a frequent complaint in children with molar incisor hypomineralisation (MIH). This double-blind randomised controlled trial aimed to evaluate non-inferiority in hypersensitivity relief of a toothpaste containing microcrystalline hydroxyapatite compared to amine fluoride in children with MIH.
METHODS: Children were randomised into 2 groups: either hydroxyapatite (intervention) or amine fluoride toothpaste (control). The primary endpoint was pain sensation in response to tactile stimulus (Wong-Baker FACES Pain Rating Scale) 56 days after randomisation and analysed by mixed effects linear regression analysis. Non-inferiority was inferred if the upper limit of the one-sided 95% confidence interval (CI) of the difference between intervention and control group was below the non-inferiority margin of 1 in the ITT (intention-to-treat) and PP (per protocol) population.
RESULTS: Twenty-one children were randomised and 14 children finished the study per protocol. In the ITT population, hydroxyapatite was non-inferior to amine fluoride (mean difference: -0.75 95%CI [-∞;0.49]). In the PP population, non-inferiority could not be shown (-0.62 [-∞;1.08]).
CONCLUSIONS: Overall non-inferiority in hypersensitivity relief of a toothpaste containing hydroxyapatite compared to amine fluoride could not be shown. However, the hydroxyapatite group tended to be less hypersensitive in both populations. Attrition of the PP population due to the COVID-19 pandemic led to loss of statistical power.

OBJECTIVE: This study aimed to assess the prevalence and clinical status of molar incisor hypomineralisation (MIH) and other enamel defects and associated factors in Libyan children.
METHODS: A cross-sectional survey of a randomly selected sample of 8- to 10-year-old Libyan school children was conducted in the city of Benghazi, Libya in 2019. The children were assessed for the presence of MIH and enamel defects according to EAPD evaluation criteria. The survey was supplemented by a questionnaire, completed by parents, about potential associated factors occurring before, around and after birth. Association with risk indicators was assessed using chi-square and Mann-Whitney U tests.
RESULTS: One thousand forty-seven children returned complete questionnaires and attended the clinical examination, with 87% response rate. MIH was the most common form of enamel defects, affecting 162 (15.5%) children. The average number of MIH affected teeth was 3.54 (SD = 1.82). There were no statistically significant associations between the prevalence of MIH and health or demographic characteristics except for the history of early childhood health problems (P = 0.047).
CONCLUSIONS: In Libyan children, MIH appeared to be the most prevalent type of enamel defects affecting 15.5% of the participants. Although not statistically significant, MIH appeared to be associated with prenatal, perinatal and post-natal challenges.

The management of compromised first permanent molars (FPMs) in children presents a clinical challenge to the dental team. Hypomineralised FPMs in molar incisor hypomineralisation (MIH) conditions could undergo post-eruptive breakdown, making them susceptible to caries, leading to their subsequent loss. The planned extraction of compromised FPMs is a valid alternative to complex restorative treatment. However, establishing the presence or absence of third permanent molars, amongst other considerations, is crucial to reaching a successful outcome. Clinicians should understand the importance of an orthodontic examination around the age of 8 years old with regard to establishing a differential therapeutic decision about the ideal timing of MIH-affected FPMs\' extraction in children. The aim of this article is to highlight that, with an interdisciplinary approach, a good outcome can be achieved following the extraction of poorly prognosed FPMs. The most cost-effective way of addressing MIH-affected FPMs is extraction, followed by orthodontic space closure when indicated. This obviates the need for the repeated restorative replacement and saves perfectly healthy premolars from being extracted for space creation in orthodontic treatment in several clinical scenarios.

OBJECTIVE: Molar incisor hypomineralisation (MIH) is a significant global health problem frequently encountered by dentists. The aim of this questionnaire-based study was to gain a better understanding of how dentists in the Republic of Ireland perceive and manage MIH. In addition, to compare these findings with results of existing international studies.
METHODS: Following ethical approval, an online survey was created consisting of 16 questions based on previous surveys regarding perception and treatment of MIH. Photographs and information regarding three specific cases were also included. The questionnaire was distributed by email and the data were analysed using SPSS statistical software.
RESULTS: The total number of respondents was 230, of which 204 were general dentists. The majority of dentists (58%) reported that they observe MIH on a weekly basis. Those dentists exclusively in private practice and respondents aged 36 and older were less likely to note frequent MIH (p = 0.042). The vast majority of respondents felt either confident or very confident in diagnosing MIH (91%). Overall, 71% reported to feel comfortable managing MIH; however, those in private practice only (p = 0.023) and those aged 36 and older (p = 0.011) were less likely to report being comfortable managing MIH. The most commonly cited barrier to care was the child\'s behaviour, followed by difficulty in achieving local anaesthesia. Composite resin was the most commonly selected material used to restore teeth affected by MIH (84%). In the scenario on cavity design, the results showed a similar number of dentists selected the most conservative and the most aggressive preparation indicating a disparity among choices.
CONCLUSIONS: MIH is frequently encountered by Irish general dentists. The overall wide disparity of responses is in line with other studies, and further highlights the need for the development of strong treatment guidelines and continuing dental education to assist dentists in treatment planning for MIH.