Alveolar Bone Research Articles

PECULIARITIES OF ORTHODONTIC TREATMENT FOR PATIENTS WITH GENERALIZED PERIODONTITIS AND PREDOMINANCE OF PARASYMPATHETIC NERVOUS SYSTEM ACTIVITY

The use of orthodontic treatment for patients with generalized periodontitis enhances the effectiveness of comprehensive care. However, it is important to consider the reduced capacity for alveolar bone regeneration in these patients. Therefore, as part of the complex treatment of generalized periodontitis, the inclusion of medications to support alveolar bone regeneration is essential. The course of various diseases can be influenced by the state of the patient’s autonomic nervous system. In this study, medications were administered to normalize parasympathetic nervous system activity in patients with generalized periodontitis undergoing orthodontic treatment. The objective of the study was to evaluate the effectiveness of orthodontic treatment in patients with generalized periodontitis, particularly those with a predominance of parasympathetic autonomic nervous system activity. This was assessed by the supplementary use of a combination of drugs designed to stimulate alveolar bone formation and regulate parasympathetic nervous system function. Materials and methods. This study involved 35 young patients (aged 18-35) with generalized periodontitis and a predominance of parasympathetic autonomic nervous system activity, all of whom presented with displacement of the maxillary frontal teeth. These patients underwent orthodontic treatment. To correct the state of the autonomic nervous system over the treatment of generalized periodontitis, patients were prescribed to take a complex of medicines including the preparation “Calcinova” for stimulating osteogenesis. A comprehensive periodontal examination, including the assessment of hygienic indices, was conducted to evaluate periodontal status throughout the treatment. Results. The periodontal examination revealed that almost all patients demonstated an improvement in oral health. Noticeable dynamics in the pathological process were observed as a result of the complex treatment. The analysis of these findings underscores the importance of orthodontic treatment for patients with generalized periodontitis, particularly when combined with methods to correct parasympathetic nervous system activity and promote osteogenesis. This approach was shown to positively affect periodontal tissues and enhance the effectiveness of generalized periodontitis treatment. Conclusions. Correction of parasympathetic autonomic nervous system function enhances the effectiveness of therapy. In this study, a complex of medications was used to improve parasympathetic nervous system activity. The addition of “Calcinova” to stimulate osteogenesis further contributed to achieving more stable treatment outcomes in patients with generalized periodontitis.

G protein-coupled receptor 91 activations suppressed mineralization in Porphyromonas gingivalis-infected osteoblasts.

Succinate receptor GPR91 is one of the G protein-coupled receptors (GPCRs) that interacts with various proteins to regulate diverse cellular functions such as cell morphology, apoptosis, and differentiation. In this study, we investigated whether the GPR91-mediated signaling pathway regulates mineralization in Porphyromonas gingivalis (P. gingivalis)-treated osteoblasts and to determine its potential role in osteoclast differentiation. Primary mouse osteoblasts from wild-type (WT) and GPR91 knockout (GPR91-/-) mice infected with P. gingivalis were used for in vitro experiments. The results showed that inhibition by 4C, a specific inhibitor, and GPR91 knockout promoted mineralization in P. gingivalis-infected osteoblasts. Surprisingly, GPR91 knockdown decreased the migration ability of osteoblasts. Moreover, compared with P. gingivalis-infected WT osteoblasts, GPR91-/- osteoblasts exhibited decreased RANKL production, and conditioned media (CM) from bacteria-infected GPR91-/- osteoblasts suppressed the formation of osteoclast precursors. Moreover, P. gingivalis mediated the role of GPR91 in osteoblast mineralization by activating the NF-κB pathway. These findings suggest that GPR91 activation reduces mineralization of P. gingivalis-infected osteoblasts and promotes osteoclastogenesis in macrophages. Therefore, targeting GPR91 may mitigate the loss of alveolar bone during bacterial infection.

Histomorphometric and Micro-CT Evaluation of Cerabone and Bio-Oss in Maxillary Sinus Lifting: A Randomized Clinical Trial

Background and Objectives: The loss of teeth in the posterior maxillary region often leads to significant alveolar bone resorption and maxillary sinus pneumatization, complicating dental implant placement. Maxillary sinus grafting, typically using autogenous bone, is a common solution. However, autogenous bone grafts require additional surgical procedures, leading to increased morbidity. This study aims to compare the efficacy of two xenografts, Bio-Oss and Cerabone, in promoting new bone formation in maxillary sinus grafting through histomorphometric analysis and micro-computed tomography (micro-CT). Materials and Methods: A total of 22 maxillary sinuses (12 right and 10 left) were grafted, with 12 using Cerabone and 10 using Bio-Oss. Six months post-grafting, biopsies were collected for histomorphometric analysis to measure new bone formation, connective tissue, and residual biomaterial. Additionally, micro-CT analysis was performed to assess bone volume fraction, trabecular thickness, number, and separation. Results: Histomorphometric analysis showed that the Cerabone group had a higher average new bone formation (25.94% ± 10.55) compared to the Bio-Oss group (17.29% ± 4.61), with a statistically significant difference (p = 0.02). Micro-CT analysis revealed that the bone volume fraction in the Cerabone group was significantly higher compared to the Bio-Oss group, with significant differences in trabecular thickness (p = 0.02) but not in trabecular number or separation. Conclusions: The study demonstrates that both xenografts are effective in promoting new bone formation in maxillary sinus grafting. However, Cerabone showed superior performance in terms of new bone formation and bone volume fraction, suggesting it may be a more effective option for maxillary sinus augmentation procedures.

Craniofacial Growth in Children With Unilateral Cleft Lip and Palate: Adopted From China Versus Born in Sweden.

In 2005, the number of internationally adopted children (IAC) with cleft lip and palate (CLP) from China increased globally, followed by an increase in the number of surgical complications. The aim was therefore to evaluate the craniofacial growth of children with unilateral CLP adopted from China and compare with non-adopted peers (NA). Cephalograms taken at 10 and 13 were analysed for the SNA, SNB, ANB, NAPg and NSBa angles. Surgical data were extracted from the medical records. The rate of secondary cleft-related surgery including secondary alveolar bone grafting (SABG) was higher in the IAC group than in the native groups. At age 10, the IAC exhibited higher SNB and NAPg and lower ANB values than the NA-Mod group and a similar pattern was observed at age 13. The IAC group demonstrated significantly lower SNA and ANB and higher NAPg values than the NA-Orig group at age 10. At age 13, lower SNA and ANB and higher SNB, NAPg, and NSBa values were observed in the IAC group compared with the NA-Orig group. Craniofacial growth is not finalized at age 13 years, why additional studies are needed to determine long-term outcomes. Results from this novel study present unfavorable craniofacial growth at age 10 and 13 years of age among IAC with UCLP and indicate an increased need for future orthognathic surgery compared with NA peers.

Hormone Replacement Therapy Relieves Periodontitis by Inhibiting Alveolar Bone Loss and Inflammation.

Hormone replacement therapy (HRT) is a commonly used strategy for treating menopausal symptoms, while its relation with periodontitis remains unclear. This study aimed to explore the potential effects of HRT on periodontitis, mainly in aspects of bone loss and inflammation. The alveolar bone height (ABH), alveolar bone thickness (ABT), and bone mineral density (BMD) were measured in menopausal women with periodontitis who had received HRT or had not received HRT by cone beam computed tomography. Based on a rat model of periodontitis, the alveolar bone loss was evaluated by micro-computed tomography and bone-related biochemical markers. The expression/levels of inflammatory markers were measured to reflect periodontal inflammation. Although the differences were not all significant in each premolars/molars, the mesial/distal ABH and buccal/lingual ABT were lower, and the mesial/distal BMD was higher in patients in the HRT group than those in the control group. In a rat model of periodontitis, the alveolar bone loss was relieved by HRT. Additionally, HRT significantly weakened the elevation of inflammatory markers, including TNF-α, IL-1β, and IL-6 in periodontitis rats. HRT contributes to the remission of periodontitis by inhibiting alveolar bone loss and inflammation.

Three-dimensional finite element analysis of occlusal stress on maxillary first molars with different marginal morphologies restored with occlusal veneers

BackgroundThere are differences in the research results regarding which edge design of occlusal veneers can achieve the best long-term success rate as a relatively new fixed prosthesis restoration method. Further research is needed. The three-dimensional finite element method was used to conduct stress analysis on occlusal veneers of maxillary first permanent molars with different thicknesses and margin preparation designs. The aim of this study was to provide mechanical research evidence and a reference for exploring standardized clinical protocols for the design of occlusal veneer restorations of maxillary first molars.MethodA 3Shape (Intraoral Scanner) was used to scan the maxillary first molar teeth in vitro, after which 3D printing was carried out. Three different edge designs were applied to identical teeth: straight-beveled finishing line(SFL), chamfer finishing line(CFL), and standard cuspal inclination(SCI). Preparation was carried out with a thickness of 0.5 mm. Using the surface deformation feature, the occlusal veneer was thickened to 0.5 mm and 1.0 mm, and periodontal ligaments were added. They were then placed into the upper and lower jaws and dental arches. Finite element analysis was performed after applying bite force dispersion to the loading area on the mandible following dynamic contact.Results(1) As the thickness increased, the maximum Von Mises stress in the occlusal veneers SFL and CFL also increased, while the SCI exhibited the opposite trend. (2). The trend of the maximum Von Mises stress in the adhesive layer decrease gradually with increasing thickness of the occlusal veneer. The stresses of the SFL and CFL is concentrated primarily at the edge position below the functional cusp, resulting in relatively low adhesive stress. However, in the SCI group, the maximum stress at the edge of the adhesive layer exceeds the maximum shear strength of commonly used adhesives.ConclusionsUnder the experimental conditions, the mechanical properties of the maximum Von Mises stress in the SFL, CFL, and SCI occlusal veneers meet clinical needs. Incorporating the minimally invasive concept of tooth preservation, a thickness of 1.0 mm are optimal for glass ceramic occlusal veneers on maxillary first molars.

Unintentionally Retained Elevator Blade Left for 8 Years Causes Mild Chronic Pain.

Fracture of surgical instruments in dental practice is not usually reported in the literature. Management involves searching for and retrieving the fragment to avoid issues such as infection, swallowing, or aspiration. Although foreign bodies may not cause symptoms for years, some can cause chronic pain. The authors describe herein the unusual case of an unintentionally retained broken elevator blade left for 8 years before being found during an orthodontic evaluation. Panoramic radiography revealed a foreign body in the alveolar bone of the right mandibular third molar that was causing mild chronic pain. The patient was unaware whether routine radiographic examination had revealed its presence. Cone-beam computer tomography was performed to identify the position of the blade fragment, and surgery was performed to retrieve it. The mild chronic pain disappeared after removal. It is advisable to use high-quality surgical instruments and to perform routine checkups before and after surgery.

A Two-Stage Approach to Alveolar Clefts Repair with Combined Cortical and Cancellous Bone Grafting

Background: Achieving optimal efficacy in secondary alveolar bone grafting (SABG) poses a considerable challenge for patients with alveolar clefts post-canine eruption. This study introduces a novel technique called the "two-stage SABG" to improve the treatment outcomes for patients who have missed the optimal timing for bone grafting. Methods: Patients aged 12 and above, presenting with unilateral, complete alveolar clefts after canine eruption, were divided into two cohorts: conventional and two-stage groups. The two-stage group underwent oronasal fistula closure and mucoperiosteal sealing during the initial stage, followed by particulate cancellous bone marrow (PCBM) and mandibular cortical bone grafting in the second stage after a three-month interval. Six months after surgery, the SABG was evaluated quantitatively and qualitatively using computed tomography (CT). Results: A total of 81 patients (median age: 14 years; male/female: 49/32) were included in the conventional group, while the two-stage group consisted of 33 patients (19 years; 20/13). The two-stage group exhibited significantly superior outcomes (P < 0.01) in terms of radiographic healing rate (> 4 points) (96.97% vs. 55.56%), bone bridge height (12.17mm, IQRs=4.26mm), bone bridge width (9.09mm, IQRs=2.74mm), bone formation rate (69.73%, IQRs=22.73%), and bone resorption rate (48.85%, IQRs=22.57%). Additionally, the average three-dimensional deviations greater than 3.5mm at the affected piriform aperture margin. Conclusions: The novel two-stage SABG approach demonstrates significant benefits in the repair of alveolar clefts and pyriform foramen deformities through combined cortical and cancellous bone grafting.

Establishment of Periodontal Ligament Stem Cell-like Cells Derived from Feeder-Free Cultured Induced Pluripotent Stem Cells.

The periodontal ligament (PDL) is a fibrous connective tissue that connects the cementum of the root to the alveolar bone. PDL stem cells (PDLSCs) contained in the PDL can differentiate into cementoblasts, osteoblasts, and PDL fibroblasts, with essential roles in periodontal tissue regeneration. Therefore, PDLSCs are expected to be useful in periodontal tissue regeneration therapy. In a previous study, we differentiated induced pluripotent stem cells (iPSCs) into PDLSC-like cells (iPDLSCs), which expressed PDL-related markers and mesenchymal stem cell (MSC) markers; they also exhibited high proliferation and multipotency. However, the iPSCs used in this differentiation method were cultured on mouse embryonic fibroblasts; thus, they constituted on-feeder iPSCs (OF-iPSCs). Considering the risk of contamination with feeder cell-derived components, iPDLSCs differentiated from OF-iPSCs (ie, OF-iPDLSCs) are unsuitable for clinical applications. In this study, we aimed to obtain PDLSC-like cells from feeder-free iPSCs (FF-iPSCs) using OF-iPDLSC differentiation method. First, we differentiated FF-iPSCs into neural crest cell-like cells (FF-iNCCs) and confirmed that FF-iNCCs expressed NCC markers (eg, Nestin and p75NTR). Then, we cultured FF-iNCCs on human primary PDL cell-derived extracellular matrix for 2 weeks; the resulting cells were named FF-iPDLSCs. FF-iPDLSCs exhibited higher expression of PDL-related and MSC markers compared with OF-iPDLSCs. FF-iPDLSCs also demonstrated proliferation and multipotency in vitro. Finally, we analyzed the ability of FF-iPDLSCs to form periodontal tissue invivo upon subcutaneous transplantation with β-tricalcium phosphate scaffolds into dorsal tissues of immunodeficient mice. Eight weeks after transplantation, FF-iPDLSCs had formed osteocalcin-positive bone/cementum-like tissues and collagen 1-positive PDL-like fibers. These results suggested that we successfully obtained PDLSC-like cells from FF-iPSCs. Our findings will contribute to the development of novel periodontal regeneration therapies.

The role of aryl hydrocarbon receptor in the occurrence and development of periodontitis

Periodontitis is a condition characterized by dysbiosis of microbiota and compromised host immunological responses, resulting in the degradation of periodontal tissues. The aryl hydrocarbon receptor (AHR), a ligand-activated transcription factor, plays a crucial role in the pathogenesis of periodontitis. AHR serves as a pivotal mediator for the adverse impacts of exogenous pollutants on oral health. Research indicates elevated expression of AHR in individuals with periodontitis compared to those without the condition. However, subsequent to the identification of endogenous AHR ligands, researches have elucidated numerous significant advantageous roles associated with AHR activation in bone, immune, and epithelial cells. This review concentrates on the modulation of the AHR pathway and the intricate functions that AHR plays in periodontitis. It discusses the characteristics of AHR ligands, detailing the established physiological functions in maintaining alveolar bone equilibrium, regulating immunity, facilitating interactions between the oral microbiome and host, and providing protection to epithelial tissues, while also exploring its potential roles in systemic disorders related to periodontitis.

Does Ovariectomy Affect the Mechanics of the Mandibular Alveolar Bone Structure of Wistar Rats Subjected to Tooth Loss and Modified Diet?—A FEA Study

The aim of this study was to evaluate the mechanical effect of ovariectomy, diet, and tooth extraction on the bone structure of the mandible of Wistar rats. Mandibles from 40 female Wistar rats were used, divided into rats with ovariectomy surgery or surgical simulation. Half of the rats had the right upper incisor extracted and a soft diet was introduced for half of the animals for 30 days. After euthanasia, microtomography of the mandibles was performed for bone segmentation to construct three-dimensional models. Each mandible was subjected to a three-point bending test. The simulation by finite element method was configured according to the protocol for positioning the part on the support and force action by the load cell defined in the mechanical tests. Stress dissipation was described qualitatively on a color scale distributed in ranges of stress values. All models showed a higher concentration of stresses in the regions of force action and in the support regions, with differences in stress values and locations. Diet and dental condition interfered in the distribution of stresses, with the lateral surface of the mandible being more influenced by diet and the medial surface of the mandible by diet and dental condition.

Assessing the Accuracy of Linear Alveolar Bone Measurements for Implant Planning Using Cone-Beam Computed Tomography by Comparing Three Competent Three-Dimensional Imaging Software: An In Vitro Study

Assessing the Accuracy of Linear Alveolar Bone Measurements for Implant Planning Using Cone-Beam Computed Tomography by Comparing Three Competent Three-Dimensional Imaging Software: An In Vitro Study

Finite element analysis of maxillary orthodontic therapies with variable alveolar bone grafts under occlusal forces in patient with unilateral cleft lip and palate

ObjectiveTo investigate the biomechanical effects of maxillary orthodontic treatment on different alveolar bone grafting positions loaded with occlusal forces in an unilateral cleft lip and palate (UCLP) patient.MethodsFinite element analysis was employed to simulate clinical scenarios more accurately by loading with occlusal forces on 8 bone-grafted models during maxillary orthodontic treatment. Displacement and von Mises stress pattern during maxillary protraction, expansion, and combined protraction and expansion were analyzed.ResultsThe seven bone-grafted models exhibited significantly smaller horizontal displacements at the non-cleft side landmarks during maxillary protraction and expansion compared to non-bone grafted models. Additionally, alveolar cleft bone grafted in the upper 1/3 and middle 1/3 exhibited greater asymmetry displacement and stress under maxillary protraction and expansion.ConclusionThe study highlights the necessity of considering occlusal forces in finite element study on orthodontic therapies for UCLP patients. The upper 1/3 and middle 1/3 bone graft conditions may require secondary bone graft supplementation to ensure the effectiveness of maxillary orthodontic treatment.

Low-Dose Cone-Beam Computed Tomography in Swedish Pediatric Patients With Alveolar Clefts Following Alveolar Bone Grafting-A Clinical Study.

The aim of this study was to investigate whether a low-dose cone-beam computed tomography (CBCT) protocol provides diagnostically acceptable image quality for assessing bone healing after alveolar bone grafting. The study cohort comprised 11 patients (aged 7-14 years) with orofacial clefts who had undergone alveolar bone grafting at Skåne University Hospital in Malmö, Sweden. During the postsurgical follow-up at 6 months, each patient was assessed twice: once with a standard-dose CBCT protocol and once with a low-dose CBCT protocol, which in total corresponds to one CBCT examination made with the exposure settings recommended by the manufacturer. Among others, the assessed parameters included subjective image quality, as well as bone graft height, thickness, and integration. No significant differences were found between the standard- and low-dose protocols for most parameters (p > 0.05). Exceptions included subjective image quality (one observer, p = 0.05) and confidence levels during the assessment (three observers, p = 0.01, 0.01, 0.02). The low-dose protocol yielded adequate image quality for postoperative CBCT healing assessment in patients who have undergone alveolar bone grafting. However, the confidence level of observers during the assessment with the low-dose protocol was reduced. This study is registered on ClinicalTrials.gov (NCT06395077). This study is registered on ClinicalTrials.gov (NCT06395077).

Experimental Periodontitis Increases Anxious Behavior and Worsens Cognitive Aspects and Systemic Oxidative Stress in Wistar Rats.

Periodontitis (PD) has the potential to induce systemic changes that affect both physical and behavioral aspects. These alterations may be associated with changes in both the inflammatory profile and the oxidative stress status of individuals with PD. Therefore, we aimed to evaluate the effects of PD on oxidative stress, as well as on behavioral parameters and cognitive impairment, in a preclinical model. Twenty-four male Wistar rats were randomly assigned to PD and sham groups. PD was induced by the ligature protocol for 14 days. Behavioral tests were initiated on the 9th day of the experiment to evaluate anxious behavior and cognition (learning and memory). After euthanasia, oxidative stress was evaluated in the gums, blood, hippocampus, and amygdala. Alveolar bone loss, bone microstructure, and elemental compositions of the mandibular bone were also assessed. PD increased alveolar bone loss, reduced the calcium and phosphorus content in the mandibular bone, and increased anxiety-like behavior and cognitive decline (p < 0.05). Furthermore, PD significantly affected the redox balance, as evidenced by increased total antioxidant capacity (TAC) in the gingiva and hippocampus (p < 0.05). It also led to increased lipid peroxidation in the gingiva and erythrocytes (p < 0.05), decreased antioxidant defenses in erythrocytes (superoxide dismutase) and the hippocampus (catalase), and increased antioxidant activity (catalase) in the amygdala (p < 0.05). PD resulted in cognitive alterations, including impairments in spatial learning and memory, as well as increased anxious behavior, likely due to redox imbalance in rats.

Regenerating Alveolar Bone for Implant Placement: The Efficacy of Autogenous Mineralized Dentin Matrix—A Systematic Review and Meta-Analysis

The preservation of the alveolar ridge has gained increasing importance for various types of rehabilitation, including dental implant placement. Consequently, researchers have explored different bone grafts, such as mineralized dentin matrix grafts. However, a comprehensive review of the efficacy of autogenous mineralized dentin (AMD) for alveolar ridge preservation remains lacking. In this review, we evaluated the efficacy of AMD as a method for alveolar ridge preservation in cases of delayed implant placement. A comprehensive search through PubMed, Google Scholar, Cochrane Library, and B-on repositories was conducted without time constraints up to July 2024 to identify peer-reviewed human studies. These studies assessed the percentage of newly formed bone and residual graft following bone regeneration with AMD grafts after tooth extraction, specifically in the context of delayed implant placement. Our analysis included four selected studies involving 55 patients and 67 sockets. The findings suggest that AMD grafts resulted in an average (and 95% confidence interval) of 43.8% [36.6%, 50.8%] newly formed bone, and delayed implant placement was a feasible surgical option for all patients. Although the available literature is scarce, AMD grafting has yielded promising outcomes as a method for bone reconstruction. Nevertheless, additional randomized controlled trials with larger sample sizes and longer follow-ups are required to substantiate these findings.

Zoledronate interrupts pre-osteoclast-induced angiogenesis via SDF-1/CXCR4 pathway

IntroductionIn this study, we tested the hypothesis that pre-osteoclast signaling is key in triggering post-traumatic angiogenesis in alveolar bone via the SDF-1/CXCR4 pathway. Interruption of osteoclast differentiation through zoledronate (Zol) disrupts the crosstalk between pre-osteoclasts and endothelial cells, hindering the initial angiogenic reaction following dental trauma. This disruption could therefore play a role in the pathogenesis of medication-related osteonecrosis of the jaw (MRONJ). MethodsThe effect of zoledronate on the expression of SDF1 was tested in pre-osteoclasts (POC) in vitro. Then, we tested the effect of pre-osteoclast conditioned medium on HUVEC cell differentiation, migration, tube-formation, and CXCR4 expression and activity in-vitro. Lastly, we quantified the effect of zoledronate treatment on post-traumatic vascular perfusion of alveolar bone, using microCT-angiography and immunohistochemistry. ResultsSDF-1 mRNA expression decreased in Zol-treated POCs (p = 0.02). Flow-Cytometry analysis showed a decrease in CXCL-12+ (SDF-1α) expressing POCs with Zol treatment (p = 0.0058). On the other hand, CXCR4 mRNA expression was significantly inhibited in Zol-treated HUVECs (p = 0.0063). CXCR4 protein expression and activity showed a corresponding dose-dependent downregulation HUVEC surface treated with conditioned media from POC treated with Zol (p = 0.008 and 0.03, respectively). Similar inhibition was observed of HUVEC migration (p = 0.0012), and tube formation (p < 0.0001), effects that were reversed with SDF-1. Finally, there was a significant reduction of CD31+ HUVECs in Alveolar bone of Zol-treated rats (p = 0.0071), confirmed by significantly lower percentage of blood vessel volume (p = 0.026), and marginally lower vessel number (p = 0.062) in the alveolar bone. ConclusionPre-osteoclasts play a crucial role in the initial angiogenic response in alveolar bone following dental extraction. Disruption of this process may be a predisposing factor to osteonecrosis.

CHILDREN WITH THIS DISEASE AND THEIR EPIDEMIOLOGY, ETIOLOGY, PREVENTION, TREATMENT

Congenital cleft lip, alveolar process and cleft palate are among the most difficult deformities of the maxillofacial region, the number of children with such deformities is 1 per 1000 newborns and continues to grow [3, 4, 13, 18]. Treatment and rehabilitation of such patients is an urgent problem due to abnormal facial development and secondary deformities, speech and chewing disorders, a long recovery period and the need for social adaptation of the child [8]. Modern literature describes the treatment of children with complications of cleft lip and palate, and there is an opinion about the need for an integrated approach [11, 19]. Children with this disease can receive full-fledged rehabilitation and social adaptation in specialized medical centers [7, 14]. The aim of the work is to demonstrate the effectiveness of interaction between orthodontists and maxillofacial surgeons on the example of a clinical case of complex rehabilitation of a patient with congenital cleft of the left upper lip, alveolar process and cleft palate.

Clinical management of mandibular permanent premolars with periapical lesion and bilateral supernumerary teeth: A 7-years follow-up case report

Objectifs: This 7-years follow-up case report describes two diversified strategies for the management of bilateral mandibular permanent premolars associated with periapical lesion and unerupted supernumerary teeth. Case Report: A non-syndromic 9 years-old Asian female patient presented pain and swelling of the 35 in anatomical contiguity with an immature and unerupted supernumerary tooth. Clinical examination revealed an intraoral vestibular sinus tract related to the necrotic 35. Periapical radiography and CBCT showed that the 35 had an immature apex associated with a periapical lesion, and a supernumerary tooth in a lingual direction. Endodontic treatment of the 35 was performed by creating an apical plug with ProRoot MTA, while the supernumerary tooth was monitored radiographically with no intervention. Four years later, the 45 developed the same clinical condition of the left arch. Radiographic examination revealed a periapical lesion with massive periapical bone resorption, and a supernumerary tooth in normal alignment. The second premolar was herein extracted to allow for eruption of the supernumerary tooth. Outcomes: 3-years follow-up revealed continued root maturation and its spontaneous eruption in the dental arch. Proper healing of both mandibular lesions was monitored after 10 months, 3-years and 7-years revealing no recurrence on both sides.

Biomechanical evaluation of implant options for unilateral maxillary defects: a finite element analysis

ObjectiveThis study aimed to evaluate stress distribution in unilateral maxillary defects using finite element analysis (FEA) to compare subperiosteal (SI) and zygomatic implants (ZI).Materials and methodsA 3D model of a unilaterally atrophied maxilla was reconstructed from CT scans. Five scenarios were simulated: (1) quad zygoma implants (SC1), (2) zygoma and conventional implants (SC2), (3) two-piece SI and conventional implants (SC3), (4) one-piece SI and conventional implants (SC4) and (5) one-piece SI implant (SC5). Mechanical properties were assigned based on data in the literature; a 450 N force for occlusal loading and a 93 N force for oblique loads were applied.ResultsUnder vertical loading, SC2 exhibited the highest tensile stress (Pmax) in the atrophic region (R-AM), while SC4 showed the lowest Pmax across the entire maxilla, indicating better stress distribution. Under oblique forces, SC2 also showed the highest Pmax in R-AM, while SC5 had the lowest Pmax overall. Minimum principal stress (Pmin) followed similar patterns, with SC4 and SC5 demonstrating lower stress levels than the other scenarios. Abutment stresses were highest in SC2 and lowest in SC4. Overall, the SI scenarios (SC3–SC5) exhibited lower stress transmission to the alveolar bone than the ZI scenarios (SC1 and SC2), with SC4 providing the most balanced stress distribution across all regions.ConclusionsSI implants, mainly the one-piece SI (SC4), offered a more favourable stress distribution than ZI implants in unilateral maxillary defects, reducing the risk of excessive bone stress. This finding suggests that SI implants may be superior for such cases, although individual patient anatomy should guide implant selection. Further clinical studies are necessary to confirm these biomechanical findings in vivo.Clinical relevanceThis study underscores the crucial role of implant selection in minimising stress on the alveolar bone in unilateral maxillary defects. Based on these findings, we recommend personalised implant strategies based on biomechanical insights to enhance outcomes in maxillofacial reconstruction.