-
Cureus May 2024Temporomandibular joint (TMJ) ankylosis results in malocclusion, poor feeding, difficulty in maintaining oral hygiene, and facial esthetic deformity. The basic surgical...
Temporomandibular joint (TMJ) ankylosis results in malocclusion, poor feeding, difficulty in maintaining oral hygiene, and facial esthetic deformity. The basic surgical objectives in the treatment of TMJ ankylosis are to establish joint movement, prevent relapse, and achieve normal growth and development. Here, we present an operated case ofsurgical correction of mandibular hypoplasia; however, the patient came back after three years due to unsatisfactory results and underwent bilateral coronoidectomy and gap arthroplasty. Bones were osteotomized at the LeFort I level and the maxillary segment was down-fractured and mobilized to bring into occlusion with the mandible. In the present case, the lower pharyngeal airway changed from 5 mm pre-treatment to 10 mm post-treatment, and the facial angle was changed from 73 to 84 post-treatment. Assessment of the pharyngeal airway is done with a high suspicion of obstructive sleep apnea and facial deformity is mandatory in the management of TMJ ankylosis.
PubMed: 38910750
DOI: 10.7759/cureus.60857 -
Korean Journal of Orthodontics Jun 2024Understanding the orofacial characteristics and growth patterns in children is essential for both orthodontics and research on children with orofacial abnormalities....
OBJECTIVE
Understanding the orofacial characteristics and growth patterns in children is essential for both orthodontics and research on children with orofacial abnormalities. However, a concise resource of normative data on the size and relative position of these structures in different populations is not available. Our objective was to aggregate normative data to assess the growth of the orofacial skeletal structures in children with a well-balanced face and normal occlusion.
METHODS
The MEDLINE, Embase, and Scopus databases were searched. Inclusion criteria included longitudinal and cross-sectional studies on cephalometric measurement of skeletal tissues and a study population ≤ 18 years with a well-balanced face and normal occlusion. Key study parameters were extracted, and knowledge was synthesized. A quality appraisal was performed using a 10-point scale.
RESULTS
The final selection comprised of 12 longitudinal and 33 cross-sectional studies, the quality of which ranged from good to excellent. Our results showed that from childhood to adulthood, the length of the cranial base increased significantly while the cranial base angle remained constant; both the maxilla and mandible moved forward and downward. The profile becomes straighter with age.
CONCLUSIONS
Growth patterns in children with a well-balanced face and normal occlusion follow accepted theories of growth.
PubMed: 38898629
DOI: 10.4041/kjod23.224 -
Journal of Applied Oral Science :... 2024To evaluate the effect of the labiolingual diameter and construction of an endodontically treated (ET) anterior tooth with crown restoration on stress distribution and...
OBJECTIVE
To evaluate the effect of the labiolingual diameter and construction of an endodontically treated (ET) anterior tooth with crown restoration on stress distribution and biomechanical safety under occlusal loading.
METHODOLOGY
Three-dimensional finite element models were generated for maxillary central incisors with all-ceramic crown restorations. The labiolingual diameters of the tooth, defined as the horizontal distance between the protrusion of the labial and lingual surfaces, were changed as follows: (D1) 6.85 mm, (D2) 6.35 mm, and (D3) 5.85 mm. The model was constructed as follows: (S0) vital pulp tooth; (S1) ET tooth; (S2) ET tooth with a 2 mm ferrule, restored with a fiber post and composite resin core; (S3) ET tooth without a ferrule, restored with a fiber post and composite resin core. A total of 12 models were developed. In total, two force loads (100 N) were applied to the crown's incisal edge and palatal surface at a 45° oblique angle to the longitudinal axis of the teeth. The Von Mises stress distribution and maximum stress of the models were analyzed.
RESULTS
Regardless of the loading location, stress concentration and maximum stress (34.07~66.78MPa) in all models occurred in the labial cervical 1/3 of each root. Both labiolingual diameter and construction influenced the maximum stress of the residual tooth tissue, with the impact of the labiolingual diameter being greater. A reduction in labiolingual diameter led to increased maximum stress throughout the tooth. The ferrule reduced the maximum stress of the core of S2 models (7.15~10.69 MPa), which is lower compared with that of S3 models (19.45~43.67 MPa).
CONCLUSION
The labiolingual diameter exerts a greater impact on the biomechanical characteristics of ET anterior teeth with crown restoration, surpassing the influence of the construction. The ferrule can reduce the maximum stress of the core and maintain the uniformity of stress distribution.
Topics: Finite Element Analysis; Crowns; Tooth, Nonvital; Humans; Biomechanical Phenomena; Incisor; Composite Resins; Dental Stress Analysis; Post and Core Technique; Reproducibility of Results; Stress, Mechanical; Reference Values; Bite Force; Imaging, Three-Dimensional; Dental Prosthesis Design; Materials Testing; Tooth Crown
PubMed: 38896638
DOI: 10.1590/1678-7757-2023-0439 -
Proceedings. Biological Sciences Jun 2024The morphology and biomechanics of infant crania undergo significant changes between the pre- and post-weaning phases due to increasing loading of the masticatory...
The morphology and biomechanics of infant crania undergo significant changes between the pre- and post-weaning phases due to increasing loading of the masticatory system. The aims of this study were to characterize the changes in muscle forces, bite forces and the pattern of mechanical strain and stress arising from the aforementioned forces across crania in the first 48 months of life using imaging and finite element methods. A total of 51 head computed tomography scans of normal individuals were collected and analysed from a larger database of 217 individuals. The estimated mean muscle forces of temporalis, masseter and medial pterygoid increase from 30.9 to 87.0 N, 25.6 to 69.6 N and 23.1 to 58.9 N, respectively (0-48 months). Maximum bite force increases from 90.5 to 184.2 N (3-48 months). There is a change in the pattern of strain and stress from the calvaria to the face during postnatal development. Overall, this study highlights the changes in the mechanics of the craniofacial system during normal development. It further raises questions as to how and what level of changes in the mechanical forces during the development can alter the morphology of the craniofacial system.
Topics: Infant; Humans; Bite Force; Biomechanical Phenomena; Skull; Child, Preschool; Tomography, X-Ray Computed; Finite Element Analysis; Female; Male; Mastication; Adaptation, Physiological; Infant, Newborn; Stress, Mechanical; Masticatory Muscles
PubMed: 38889789
DOI: 10.1098/rspb.2024.0654 -
Journal of Pharmacy & Bioallied Sciences Apr 2024This study aimed to conduct a human study to determine the incidence of postobturation pain using different parameters. In this cross-sectional study, 240 patients were...
Incidence of Postoperative Pain After Single- and Multiple-Visit Root Canal Treatment in Patients Reporting in the Conservative Dentistry and Endodontics Outpatient Department of a Tertiary Care Hospital: A Cross-Sectional Study.
This study aimed to conduct a human study to determine the incidence of postobturation pain using different parameters. In this cross-sectional study, 240 patients were included, which were equally allocated into two groups: single visit and multiple visit, 120 in each. Patients in both the single and multiple visits were further categorized into two subgroups, subgroup 1-no occlusal reduction and subgroup 2-occlusion reduction each having 60 patients. Corresponding to the type of visit, patients were followed by the role of medication into two groups, subgroup 1-both analgesics and antibiotics, subgroup 2-only analgesics, and subgroup 3-no medication. Following this approach and the criteria of the study, patients' performa was made, and based on this performa, the intensity of subjective symptoms, particularly postobturation pain, was determined using the visual analog scale (VAS). The data were then analyzed using the Chi-square test. Results were such that a single visit, no occlusal reduction, and only analgesics will be better for patients with irreversible pulpitis as chosen in the present study. Within the limitations of the present study, it can be concluded that single-sitting root canal treatment should be preferred over multiple sitting where there is no periapical inflammation; also, the occlusal reduction could be exempted from the same. To relieve the patient from postoperative pain where complete debridement is possible, antibiotics can be excluded from the regimen and only analgesics could be prescribed.
PubMed: 38882820
DOI: 10.4103/jpbs.jpbs_524_23 -
Journal of Pharmacy & Bioallied Sciences Apr 2024Class II malocclusions are a common orthodontic problem, often requiring comprehensive treatment to achieve proper occlusion and facial harmony. Early orthodontic...
BACKGROUND
Class II malocclusions are a common orthodontic problem, often requiring comprehensive treatment to achieve proper occlusion and facial harmony. Early orthodontic intervention in the mixed dentition phase has been advocated to address these issues.
MATERIALS AND METHODS
A retrospective analysis was conducted on a cohort of 150 patients with class II malocclusions who underwent early orthodontic treatment between the ages of 7 and 10 years. The treatment included fixed or removable appliances, headgear, and functional appliances, depending on individual needs. Records of their initial malocclusion severity, treatment modalities, and long-term follow-up data (mean follow-up duration of 10 years) were collected and analyzed. Stability was assessed by evaluating overjet and overbite changes from post-treatment to the long-term follow-up.
RESULTS
The initial mean overjet and overbite values were 8.5 mm and 4.0 mm, respectively. Following early orthodontic intervention, these values were significantly reduced to 3.0 mm and 1.5 mm, respectively ( < 0.001). At the long-term follow-up, the mean overjet and overbite remained stable at 3.2 mm and 1.6 mm, respectively. Analysis revealed that 85% of patients maintained their corrected class II occlusion within clinically acceptable limits, while 15% experienced minor relapse requiring minimal additional treatment.
CONCLUSION
Early orthodontic treatment in class II malocclusions can lead to significant improvements in overjet and overbite, and these corrections tend to remain stable over the long term.
PubMed: 38882812
DOI: 10.4103/jpbs.jpbs_1171_23 -
BMC Oral Health Jun 2024Tooth avulsion represents the most severe form of dental trauma, necessitating tooth replantation as the primary treatment. However, the risk of replacement root...
BACKGROUND
Tooth avulsion represents the most severe form of dental trauma, necessitating tooth replantation as the primary treatment. However, the risk of replacement root resorption (RRR) poses a significant threat to tooth retention following replantation. This study preliminarily aimed to investigate the effect of physiological occlusal force on RRR after the replantation of avulsed teeth and to explore the potential underlying mechanisms.
METHODS
Thirty-six 4-week-old male Sprague-Dawley rats underwent extraction and immediate replantation of their left maxillary molars. The rats were randomly divided into two major groups: the occluded (n = 18) group, where the opposite mandibular teeth were preserved; non-occluded (n = 18) group, where the opposite mandibular teeth were extracted. Within each major group, there were three subgroups corresponding to 7 days, 14 days, and 2 months, resulting in a total of six subgroups, (n = 6 per subgroup). The right maxillary first molars served as the normal control. Various periodontal characteristics were assessed using haematoxylin-eosin (H&E), tartrate-resistant acid phosphatase (TRAP) staining, and micro-computed tomography (micro-CT).
RESULTS
Histological staining revealed that under occlusal force, the early stage (day 7) after tooth replantation mainly manifested as root surface resorption, especially in the non-occluded group, which gradually diminished over time. Cementum and periodontal ligament (PDL) repair was observed on day 14. Micro-CT analysis indicated a significant decrease in PDL width in the non-occluded group two months after replantation, consistent with the histological findings, signifying severe RRR in the non-occluded group.
CONCLUSIONS
This study provides preliminary evidence that physiological occlusal force may attenuate osteoclastogenesis during the early stage of tooth replantation, thereby reducing the occurrence of RRR and promoting periodontal healing.
Topics: Animals; Root Resorption; Tooth Replantation; Male; Rats, Sprague-Dawley; Tooth Avulsion; Rats; Bite Force; X-Ray Microtomography; Molar
PubMed: 38840089
DOI: 10.1186/s12903-024-04394-4 -
BDJ Open Jun 2024Dental implantation has emerged as an efficient substitute for missing teeth, which is essential for restoring oral function and aesthetics. Compared to traditional...
INTRODUCTION
Dental implantation has emerged as an efficient substitute for missing teeth, which is essential for restoring oral function and aesthetics. Compared to traditional denture repair approaches, dental implants offer better stability and sustainability. The position, angle, and depth of dental implants are crucial factors for their long-term success and necessitate high-precision operation and technical support.
METHOD
We propose an integrated dual-arm high-precision oral implant surgery navigation positioning system and a corresponding control strategy. Compared with traditional implant robots, the integrated dual-arm design greatly shortens the preparation time before surgery and simplifies the operation process. We propose a novel control flow and module for the proposed structure, including an Occluded Target Tracking Module (OTTM) for occlusion tracking, a Planting Plan Development Module (PPDM) for generating implant plans, and a Path Formulation Module (PFM) for controlling the movement path of the two robot arms.
RESULT
Under the coordinated control of the aforementioned modules, the robot achieved excellent accuracy in clinical trials. The average angular error and entry point error for five patients who underwent implant surgery using the proposed robot were 2.1° and 0.39 mm, respectively.
CONCLUSION
In essence, our study introduces an integrated dual-arm high-precision navigation system for oral implant surgery, resolving issues like lengthy preoperative preparation and static surgical planning. Clinical results confirm its efficacy, emphasizing its accuracy and precision in guiding oral implant procedures.
PubMed: 38830840
DOI: 10.1038/s41405-024-00231-6 -
BMC Oral Health Jun 2024Immature teeth with necrotic pulps present multiple challenges to clinicians. In such cases, regenerative endodontic procedures (REPs) may be a favorable strategy....
BACKGROUND
Immature teeth with necrotic pulps present multiple challenges to clinicians. In such cases, regenerative endodontic procedures (REPs) may be a favorable strategy. Cells, biomaterial scaffolds, and signaling molecules are three key elements of REPs. Autologous human dental pulp cells (hDPCs) play an important role in pulp regeneration. In addition, autologous platelet concentrates (APCs) have recently been demonstrated as effective biomaterial scaffolds in regenerative dentistry, whereas the latest generation of APCs-concentrated growth factor (CGF), especially liquid phase CGF (LPCGF)-has rarely been reported in REPs.
CASE PRESENTATION
A 31-year-old woman presented to our clinic with the chief complaint of occlusion discomfort in the left mandibular posterior region for the past 5 years. Tooth #35 showed no pulp vitality and had a periodontal lesion, and radiographic examination revealed that the tooth exhibited extensive periapical radiolucency with an immature apex and thin dentin walls. REP was implemented via transplantation of autologous hDPCs with the aid of LPCGF. The periodontal lesion was managed with simultaneous periodontal surgery. After the treatment, the tooth was free of any clinical symptoms and showed positive results in thermal and electric pulp tests at 6- and 12-month follow-ups. At 12-month follow-up, radiographic evidence and three-dimensional models, which were reconstructed using Mimics software based on cone-beam computed tomography, synergistically confirmed bone augmentation and continued root development, indicating complete disappearance of the periapical radiolucency, slight lengthening of the root, evident thickening of the canal walls, and closure of the apex.
CONCLUSION
hDPCs combined with LPCGF represents an innovative and effective strategy for cell-based regenerative endodontics.
Topics: Humans; Female; Adult; Dental Pulp; Regenerative Endodontics; Dental Pulp Necrosis; Cell Transplantation; Transplantation, Autologous
PubMed: 38824565
DOI: 10.1186/s12903-024-04410-7 -
World Journal of Emergency Surgery :... May 2024Resuscitative endovascular balloon occlusion of the aorta (REBOA) has been used to control massive hemorrhages. Although there is no consensus on the efficacy of REBOA,... (Observational Study)
Observational Study
BACKGROUND
Resuscitative endovascular balloon occlusion of the aorta (REBOA) has been used to control massive hemorrhages. Although there is no consensus on the efficacy of REBOA, it remains an option as a bridging therapy in non-trauma centers where trauma surgeons are not available. To better understand the current landscape of REBOA application, we examined changes in its usage, target population, and treatment outcomes in Japan, where immediate hemostasis procedures sometimes cannot be performed.
METHODS
This retrospective observational study used the Japan Trauma Data Bank data. All cases in which REBOA was performed between January 2004 and December 2021 were included. The primary outcome was the in-hospital mortality rate. We analyzed mortality trends over time according to the number of cases, number of centers, severity of injury, and overall and subgroup mortality associated with REBOA usage. We performed a logistic analysis of mortality trends over time, adjusting for probability of survival based on the trauma and injury severity score.
RESULTS
Overall, 2557 patients were treated with REBOA and were deemed eligible for inclusion. The median age of the participants was 55 years, and male patients constituted 65.3% of the study population. Blunt trauma accounted for approximately 93.0% of the cases. The number of cases and facilities that used REBOA increased until 2019. While the injury severity score and revised trauma score did not change throughout the observation period, the hospital mortality rate decreased from 91.3 to 50.9%. The REBOA group without severe head or spine injuries showed greater improvement in mortality than the all-patient group using REBOA and all-trauma patient group. The greatest improvement in mortality was observed in patients with systolic blood pressure ≥ 80 mmHg. The adjusted odds ratios for hospital mortality steadily declined, even after adjusting for the probability of survival.
CONCLUSIONS
While there was no significant change in patient severity, mortality of patients treated with REBOA decreased over time. Further research is required to determine the reasons for these improvements in trauma care.
Topics: Humans; Balloon Occlusion; Japan; Male; Female; Retrospective Studies; Middle Aged; Resuscitation; Injury Severity Score; Adult; Endovascular Procedures; Aged; Hospital Mortality; Aorta; Wounds and Injuries; Hemorrhage
PubMed: 38822409
DOI: 10.1186/s13017-024-00548-5