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Tomographic images of two contiguous submerged roots, in the Intermediate Phase of Evolution, still showing punctual presence of periodontal space, areas with alveolodental ankylosis and replacement tooth resorption on the majority of surfaces.
Source publication
Introduction
In clinical practice, submerged roots are found with high frequency, and their presence can change the planning of dental movements and implant placement.
Objectives
To provide explanations of possible developments in the area involved, according to the evolutionary stage of the process, at the time of diagnosis.
Discussion
After atr...
Context in source publication
Context 1
... there is movement of a tooth to the site when the root is still in the intermediate or advanced phase of evolution, there will be a "bone" density (Figs 3 and 4) that may lead to a considerable risk of lateral root resorption, as if it were an area of idiopathic osseous osteosclerosis or a focal sclerosing osteitis. 6 In this situation, if you assume the risks and choose to move a tooth towards these denser areas, you should reduce the intensity of the force by between 20 and 30%, and prioritize the distribution of forces along the root of the tooth. ...
Citations
... For example, excessive stress concentrations in the posterior region could increase the risk of root resorption and damage to the periodontal membrane, potentially leading to irreversible changes in the tooth's support structure. In contrast, an even stress distribution can promote more controlled tooth movements and enhance treatment stability, especially during mandibular advancement (Consolaro et al., 2023). Our study observed that when the mandibular advancement distance was equal or slightly excessed the occlusal opening distance, the stress on posterior PDL decreased and became more evenly distributed. ...
Introduction
This study aimed to evaluate the biomechanical effects of different mandibular movements and torque compensations during mandibular advancement with clear aligners using finite element analysis.
Methods
Models were constructed to include the mandible, teeth, periodontal ligament (PDL), and clear aligners with buccal wings. Five oral muscles (superficial masseter, deep masseter, medial temporalis, posterior temporalis, and medial pterygoid) were represented as springs. Muscle values were measured and applied during different mandibular movements, including advancement distances (1–7 mm) and occlusal opening distances (2–4 mm). Different torque compensation angles (0°, 1°, 2°, and 3°) were applied to the mandibular central incisor.
Results
When the mandibular advancement was equal to or slightly excessed the occlusal opening distance, stress on the posterior PDL decreased and became more evenly distributed. Increasing the occlusal opening distance significantly raised stress on the posterior PDL and caused grater labial inclination of the mandibular anterior teeth. As the torque compensation increased, the labial inclination of the mandibular central incisor decreased, but stress on the PDL increased. Nearly complete bodily movement of the lower central incisor was achieved with torque compensation angles of approximately 15°, 19°, and 20° in models M1-2, M2-3, and M3-4, respectively.
Conclusion
To maintain periodontal health during mandibular advancement, it is recommended that the mandibular advancement distance be equal to or slightly excessed the occlusal opening distance. Excessive occlusal opening distance increases stress on the posterior PDL and the labial inclination of mandibular anterior teeth, requiring careful control. Additionally, proper torque control of the mandibular interior teeth is crucial for optimal outcomes.
