Oral

Background/objectives: Zirconia dental implants are increasingly recognised as an alternative to titanium implants due to their biocompatibility and aesthetics. Initially developed as one-piece systems, zirconia implants have evolved into two-piece designs with different platform levels; however, comparative data on their primary and secondary stability– particularly as assessed by resonance frequency analysis (RFA)—and marginal bone dynamics remain limited. This case series aimed to evaluate the implant stability and marginal bone changes of two-piece zirconia implants with bone-level (BL) and tissue-level (TL) platforms in patients missing maxillary premolars. Methods: Thirteen zirconia implants (n = 13; 7 BL, 6 TL; Z5-TL/Z5-BL, Z-Systems, Switzerland) were placed in 11 patients with healed ridges. The implant stability quotient (ISQ) was measured immediately after insertion and before prosthetic loading. Lithium disilicate crowns were cemented after four months, and follow-ups were conducted for an average of 35 months (SD = 12). Results: Initial ISQ values ranged from 73 to 79, increasing to 76–84 at 3–4 months, indicating high implant stability for both BL and TL implants. The extent of marginal bone loss (MBL) after two years was greater around BL implants (mean 0.46 mm) compared to TL implants (mean 0.2 mm), although probing depths and bleeding on probing remained minimal in both groups, with only one TL implant showing gingival recession. Conclusions: Over a short observation period, two-piece zirconia implants with tissue-level platforms appeared to demonstrate superior marginal tissue stability. Further, larger-scale controlled studies are required to confirm these preliminary observations.

Molar incisor hypomineralisation (MIH) is a developmental defect affecting permanent first molars and often the incisors too. Hypomineralised second primary molars (HSPM) have been proposed as potential early indicators of MIH. Aim: The aim was to identify potential aetiological factors associated with MIH and assess their relationship with HSPM in a pilot study. Methods: A cross-sectional case–control study was conducted with 120 patients (60 cases and 60 controls), aged 7–15 years, from the Paediatric Dentistry Postgraduate Programme. MIH was diagnosed following European Academy of Paediatric Dentistry (EAPD) guidelines. Parents completed a structured questionnaire on potential aetiological factors. Results: MIH was significantly associated with maternal smoking during pregnancy (p = 0.013), birth hypoxia (p = 0.013) and the use of amoxicillin and inhalation therapy during infancy (p < 0.001). It was also associated with tonsillitis (p = 0.022), bronchiolitis (p = 0.005) and other respiratory disorders (p = 0.049). HSPM was associated with anaemia and hypotension during pregnancy (p = 0.001), bottle-feeding (p = 0.044) and urinary tract infections (p = 0.003). No statistically significant association was found between MIH and HSPM. Conclusions: This pilot study has identified specific prenatal, perinatal, and postnatal factors associated with MIH and HSPM. The findings emphasise the clinical relevance for early diagnosis and management and highlight the need for studies with larger sample sizes to validate these associations.

Introduction: Infantile Refsum disease (IRD) is considered one of the milder phenotypes within the Zellweger Spectrum Disorders (ZSDs), a group of peroxisomal biogenesis disorders characterized by a generalized impairment of peroxisomal function. Pathognomonic features of IRD are growth retardation, hearing and cognitive impairment, neuromuscular problems, and craniofacial anomalies. Due to the relatively short lifespan, severe dental anomalies have not been previously reported in association with this disorder. This case report describes a rare manifestation of multiple impacted teeth and near complete edentulism in an adult patient diagnosed with Infantile Refsum disease (IRD). Material and Methods: The patient, a 24-year-old female, presented with a skeletal Class III malocclusion, severe maxillary hypoplasia, and complete impaction of the permanent dentition. The diagnosis of Infantile Refsum disease (IRD) was genetically confirmed and was associated with both neurological and dermatological manifestations. Conclusions: This case underscores that severe disturbances in tooth eruption and impaction may represent underrecognized manifestations of metabolic and genetic disorders such as Infantile Refsum disease (IRD). Dental professionals should remain vigilant to the potential association between systemic conditions and delayed or failed tooth eruption, emphasizing the need for interdisciplinary management and further investigation.