During development, tooth germs undergo various morphological changes resulting from interactions between the oral epithelium and ectomesenchyme. These processes are influenced by the extracellular matrix, the composition of which, along with cell adhesion and signaling, is regulated by metalloproteinases. Notably, these include matrix metalloproteinases (MMPs), a disintegrin and metalloproteinases (ADAMs), and a disintegrin and metalloproteinases with thrombospondin motifs (ADAMTSs). Our analysis of previously published scRNAseq datasets highlight that these metalloproteinases show dynamic expression patterns during tooth development, with expression in a wide range of cell types, suggesting multiple roles in tooth morphogenesis. To investigate this, Marimastat, a broad-spectrum inhibitor of MMPs, ADAMs, and ADAMTSs, was applied to ex vivo cultures of mouse molar tooth germs. The treated samples exhibited significant changes in tooth germ size and morphology, including an overall reduction in size and an inversion of the typical bell shape. The cervical loop failed to extend, and the central area of the inner enamel epithelium protruded. Marimastat treatment also disrupted proliferation, cell polarization, and organization compared with control tooth germs. In addition, a decrease in laminin expression was observed, leading to a disruption in continuity of the basement membrane at the epithelial-mesenchymal junction. Elevated hypoxia-inducible factor 1-alpha gene (Hif-1α) expression correlated with a disruption to blood vessel development around the tooth germs. These results reveal the crucial role of metalloproteinases in tooth growth, shape, cervical loop elongation, and the regulation of blood vessel formation during prenatal tooth development.NEW & NOTEWORTHY Inhibition of metalloproteinases during tooth development had a wide-ranging impact on molar growth affecting proliferation, cell migration, and vascularization, highlighting the diverse role of these proteins in controlling development.

• MeSH
• Hypoxia-Inducible Factor 1, alpha Subunit metabolism   genetics   MeSH
• Matrix Metalloproteinase Inhibitors pharmacology   MeSH
• Hydroxamic Acids pharmacology   MeSH
• Metalloproteases metabolism   genetics   MeSH
• Molar embryology   growth & development   metabolism   enzymology   MeSH
• Morphogenesis MeSH
• Mice, Inbred C57BL MeSH
• Mice MeSH
• Odontogenesis * MeSH
• Cell Proliferation * MeSH
• Gene Expression Regulation, Developmental MeSH
• Tooth Germ embryology   metabolism   enzymology   MeSH
• Animals MeSH
• Check Tag
• Mice MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH

OBJECTIVES: This case series evaluated the clinical efficacy of the novel "lateral approach" combined with an enamel matrix derivative (EMD) and bone grafting in the regenerative surgical treatment of intrabony defects associated with an edentulous ridge. MATERIAL AND METHODS: The innovative flap, called the "lateral approach," is explicitly designed for regeneration of unchallenged isolated intrabony defects associated with edentulous alveolar ridges. The flap is defined by a curved vertical incision on the buccal side opposite the treated defect and a sulcular incision on the buccal and defect-associated sides, promoting uneventful healing and regeneration while minimizing complications. Seven intrabony defects (one per patient) distal to the lower second molar were treated using the "lateral approach" combined with EMD and grafting with deproteinized bovine bone mineral. The primary outcome was clinical attachment level (CAL) change. As additional parameters, pocket probing depth (PPD) reduction and complication rate were analyzed. All the outcomes were assessed 6 months post-surgery and compared with the baseline values. RESULTS: Primary wound healing occurred in 100% of cases, and no complications were reported. At the 6-month re-evaluation, the initial median CAL of 6 mm (interquartile range 5-8 mm) was reduced to 3 mm (3-5 mm). The corresponding median PPD was reduced from 6 mm (IQR 6-8 mm) to 4 mm (IQR 3-5 mm). These differences were statistically significant (p < 0.05). CONCLUSIONS: The "lateral approach" is a technique for the surgical treatment of intrabony defects associated with the edentulous ridge. Within the limitations of the study, this method seems to be suitable for distal intrabony defects in the lower second molars, which frequently develop after third molar extraction.

• MeSH
• Alveolar Ridge Augmentation * methods   MeSH
• Jaw, Edentulous surgery   MeSH
• Surgical Flaps transplantation   MeSH
• Adult MeSH
• Wound Healing MeSH
• Bone Substitutes therapeutic use   MeSH
• Middle Aged MeSH
• Humans MeSH
• Prospective Studies MeSH
• Dental Enamel Proteins therapeutic use   MeSH
• Bone Regeneration MeSH
• Alveolar Bone Loss * surgery   MeSH
• Guided Tissue Regeneration, Periodontal methods   MeSH
• Aged MeSH
• Bone Transplantation methods   MeSH
• Treatment Outcome MeSH
• Check Tag
• Adult MeSH
• Middle Aged MeSH
• Humans MeSH
• Male MeSH
• Aged MeSH
• Female MeSH
• Publication type
• Journal Article MeSH

PURPOSE: Adhesive remnants removal is the last key step influencing orthodontic treatment outcomes. Four different clearance methods (CM) of orthodontic adhesive were evaluated to determine, which achieved the smoothest enamel surface in the shortest time. MATERIALS AND METHODS: 75 intact premolars extracted for orthodontic purposes were included, sixty had an orthodontic bracket bonded and subsequently removed, and fifteen served as the control group. Four CMs were used to clear the tooth surface of 15 premolars each: carbide bur (CB), carbide bur with titanium nitride surface treatment + fine carbide bur (CBCB), glass fiber-reinforced composite instrument (GFCB), zirconia bur + glass fiber-reinforced composite bur (ZBCB). The processing time was recorded. In ten premolars from each group, the enamel surface was evaluated by atomic force microscopy estimating mean roughness (Ra), roughness profile value (Rq), and roughness depth (Rt). Enamel Damage Index (EDI) was assessed with a scanning electron microscope on 5 remaining premolars. RESULTS: Significant differences were observed in all evaluated parameters - Ra (p<0.0001), Rq (p<0.0001), and Rt (p<0.0001). GFCB exhibited the smoothest surface in all parameters. The lowest EDI exhibited teeth treated by GFCB, however, the differences were not significant. Working with GFCB took the longest time (mean 116 s), and the shortest with CBCB (mean 49 s). CONCLUSION: Using CB is the fastest clearance method, but the enamel surface roughness was highest. Clearing with a set of instruments CBCB proved to be a fast method with satisfying remaining enamel roughness.

• Publication type
• Journal Article MeSH

KEY CLINICAL MESSAGE: In the anatomically complex terrain of the head and neck, the use of 3D intraoperative models serves as an effective verification tool, determining the size, shape, and number of foreign bodies. This allows the main operator to maximize their capacities for careful wound revision and receive real-time information about the remaining content of the sought-after bodies. ABSTRACT: Penetrating foreign bodies of various origins in the head and neck are uncommon, but potentially hazardous injuries. Complete removal of foreign bodies from soft tissues is essential for optimal healing, minimizing complications, and significantly reducing the risk of the need for reoperation. Despite various technological systems and safeguards available, unintentionally retained surgically placed foreign bodies remain difficult to eliminate completely. A 34-year-old female patient with a cut on the right side of her face who was initially treated with sutures at a general surgical clinic presented for a follow-up examination. A foreign body was verified subcutaneously on the anterior-posterior x-ray image on the right side. Computed tomography confirmed a total of 7 foreign bodies with a density corresponding to dental enamel, distributed subcutaneously, subfascially, and intramuscularly in the right temporal region. As part of the preoperative preparation and analysis, the bone segment of the right temporal fossa with the zygomatic bone and the glass fragments were segmented from the CT data and printed on an SLA printer. The physical 3D models were autoclave sterilized and present during surgery. The position, shape, and number of each individual glass fragment was compared with 3D-printed one. The benefits of producing 3D models of foreign bodies are undeniable, particularly in their perioperative comparison with the removed foreign bodies from wounds.

• Publication type
• Journal Article MeSH
• Case Reports MeSH

OBJECTIVES: This study presents biological affinities between the last hunter-fisher-gatherers and first food-producing societies from the Nile Valley. We investigate odontometric and dental tissue proportion changes between these populations from the Middle Nile Valley and acknowledge the biological processes behind them. MATERIALS AND METHODS: Dental remains of 329 individuals from Nubia and Central Sudan that date from the Late Pleistocene to the mid-Holocene are studied. Using 3D imaging techniques, we investigated outer and inner metric aspects of upper central incisors, and first and second upper molars. RESULTS: Late Paleolithic and Mesolithic foragers display homogeneous crown dimensions, dental tissue proportions, and enamel thickness distribution. This contrasts with Neolithic trends for significant differences from earlier samples on inner and outer aspects. Finally, within the Neolithic sample differences are found between Nubian and Central Sudanese sites. DISCUSSION: Substantial dental variation appears to have occurred around 6000 bce in the Nile Valley, coinciding with the emergence of food-producing societies in the region. Archeological and biological records suggest little differences in dietary habits and dental health during this transition. Furthermore, the substantial variations identified here would have happened in an extremely short time, a few centuries at most. This does not support in situ diet-related adaptation. Rather, we suggest these data are consistent with some level of population discontinuity between the Mesolithic and Neolithic samples considered here. Complex settlement processes could also explain the differences between Nubia and Central Sudan, and with previous results based on nonmetric traits.

• MeSH
• History, Ancient MeSH
• Diet history   MeSH
• Adult MeSH
• Humans MeSH
• Molar anatomy & histology   MeSH
• Paleodontology * MeSH
• Incisor anatomy & histology   MeSH
• Tooth anatomy & histology   chemistry   MeSH
• Check Tag
• History, Ancient MeSH
• Adult MeSH
• Humans MeSH
• Male MeSH
• Female MeSH
• Publication type
• Journal Article MeSH
• Historical Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Geographicals
• Sudan MeSH

OBJECTIVE: Dental hypersensitivity remains widespread, underscoring the need for materials that can effectively seal dental tubules. This study evaluated the potential of bioactive-glass-infused hydroxyethyl cellulose gels in this context. METHODS: Five gels were synthesized, each containing 20% bioactive glass (specifically, 45S5, S53P4, Biomin F, and Biomin C), with an additional blank gel serving as a control. Subjected to two months of accelerated aging at 37 ± 2 °C, these gels were assessed for key properties: viscosity, water disintegration time, pH level, consistency, adhesion to glass, and element release capability. RESULTS: Across the board, the gels facilitated the release of calcium, phosphate, and silicon ions, raising the pH from 9.00 ± 0.10 to 9.7 ± 0.0-a range conducive to remineralization. Dissolution in water occurred within 30-50 min post-application. Viscosity readings showed variability, with 45S5 reaching 6337 ± 24 mPa/s and Biomin F at 3269 ± 18 mPa/s after two months. Initial adhesion for the blank gel was measured at 0.27 ± 0.04 Pa, increasing to 0.73 ± 0.06 Pa for the others over time. Gels can release elements upon contact with water (Ca- Biomin C 104.8 ± 15.7 mg/L; Na- Biomin F 76.30 ± 11.44 mg/L; P- Biomin C 2.623 ± 0.393 mg/L; Si- 45S5-45.15 ± 6.77mg/L, F- Biomin F- 3.256 ± 0.651mg/L; Cl- Biomin C 135.5 ± 20.3 mg/L after 45 min). CONCLUSIONS: These findings highlight the gels' capacity to kickstart the remineralization process by delivering critical ions needed for enamel layer reconstruction. Further exploration in more dynamic, real-world conditions is recommended to fully ascertain their practical utility.

• Publication type
• Journal Article MeSH

PATIENTS: This case report presents a minimally invasive approach to replace a missing mandibular lateral incisor using a dual-injection molding technique with flowable composite resins. Integrated with a comprehensive digital workflow, this method achieves a structurally and esthetically biomimetic, bi-layered prosthetic solution. A 34-year-old woman with congenital absence of a mandibular lateral incisor was successfully rehabilitated using a direct composite resin-bonded fixed partial denture (RBFPD). DISCUSSION: Two specialized three-dimensional (3D)-printed flexible indices stabilized by a custom-designed 3D-printed rigid holder were employed to ensure the meticulous injection molding of flowable composite resins formulated to emulate the inherent chromatic gradations between dentin and enamel. The inherent flexibility of the indices, combined with the holder, facilitated accurate and seamless adaptation to the complex morphological features of the dental arch, thereby mitigating the challenges commonly associated with rigid 3D-printed resin indices. CONCLUSIONS: The bilayered direct composite RBFPD using 3D printed flexible indices prepared with a full digital workflow has several advantages over other dental prosthetic solutions, including noninvasiveness, cost-effectiveness, biomimetic esthetics, repairability, and shortened treatment times. Although the initial results are promising, further longitudinal studies with larger patient cohorts are required to confirm the long-term efficacy of this approach.

• MeSH
• Printing, Three-Dimensional * MeSH
• Anodontia rehabilitation   therapy   MeSH
• Biomimetics MeSH
• Adult MeSH
• Humans MeSH
• Mandible * MeSH
• Incisor * MeSH
• Composite Resins * MeSH
• Denture, Partial, Fixed, Resin-Bonded MeSH
• Check Tag
• Adult MeSH
• Humans MeSH
• Female MeSH
• Publication type
• Journal Article MeSH
• Case Reports MeSH

• MeSH
• Stomatognathic System Abnormalities diagnosis   therapy   MeSH
• Amelogenesis Imperfecta * diagnosis   therapy   MeSH
• Humans MeSH
• Rare Diseases diagnosis   therapy   MeSH
• Check Tag
• Humans MeSH
• Publication type
• Case Reports MeSH
• Review MeSH

AIM: Fas ligand (FasL) belongs to the tumour necrosis factor superfamily regulating bone turnover, inflammation, and apoptosis. The appendicular and axial skeleton phenotype of mature Faslgld mice has been reported. The impact of FasL on the alveolar bone providing support for the teeth at mature stages under healthy and induced inflammatory conditions remains unknown. MATERIALS AND METHODS: We performed a phenotypical analysis of mice carrying the homozygous Faslgld mutation and wild-type (WT) mice (C57BL/6) under healthy conditions and upon ligature-induced periodontitis. After 12 days, micro-computed tomography analysis revealed the distance between the cement enamel junction and the alveolar bone crest. Additional structural parameters, such as the bone volume fraction (BV/TV) and the periodontal ligament space volume, were measured. Histological analyses were performed to visualize the catabolic changes at the defect site. RESULTS: Healthy Faslgld mice were found to have more periodontal bone than their WT littermates. Faslgld had no significant effect on inflammatory osteolysis compared to WT controls with ligatures. Histology revealed eroded surfaces at the root and in the inter-proximal bone in both strains. CONCLUSIONS: Our findings suggest that FasL is a catabolic factor in alveolar bone homeostasis but it does not affect the inflammatory osteolysis.

• MeSH
• Homeostasis MeSH
• Fas Ligand Protein MeSH
• Mice, Inbred C57BL MeSH
• Mice MeSH
• Osteolysis * MeSH
• X-Ray Microtomography MeSH
• Animals MeSH
• Check Tag
• Mice MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH

Ameloblasts are specialized epithelial cells in the jaw that have an indispensable role in tooth enamel formation-amelogenesis1. Amelogenesis depends on multiple ameloblast-derived proteins that function as a scaffold for hydroxyapatite crystals. The loss of function of ameloblast-derived proteins results in a group of rare congenital disorders called amelogenesis imperfecta2. Defects in enamel formation are also found in patients with autoimmune polyglandular syndrome type-1 (APS-1), caused by AIRE deficiency3,4, and in patients diagnosed with coeliac disease5-7. However, the underlying mechanisms remain unclear. Here we show that the vast majority of patients with APS-1 and coeliac disease develop autoantibodies (mostly of the IgA isotype) against ameloblast-specific proteins, the expression of which is induced by AIRE in the thymus. This in turn results in a breakdown of central tolerance, and subsequent generation of corresponding autoantibodies that interfere with enamel formation. However, in coeliac disease, the generation of such autoantibodies seems to be driven by a breakdown of peripheral tolerance to intestinal antigens that are also expressed in enamel tissue. Both conditions are examples of a previously unidentified type of IgA-dependent autoimmune disorder that we collectively name autoimmune amelogenesis imperfecta.

• MeSH
• Ameloblasts metabolism   MeSH
• Amelogenesis Imperfecta * complications   immunology   MeSH
• Antigens immunology   metabolism   MeSH
• Polyendocrinopathies, Autoimmune * complications   immunology   MeSH
• Autoantibodies * immunology   MeSH
• Celiac Disease * complications   immunology   MeSH
• Immunoglobulin A immunology   MeSH
• Humans MeSH
• AIRE Protein deficiency   MeSH
• Proteins immunology   metabolism   MeSH
• Intestines immunology   metabolism   MeSH
• Dental Enamel immunology   metabolism   MeSH
• Check Tag
• Humans MeSH
• Publication type
• Journal Article MeSH