RESUMO
Objective@#To analyze the ability of micro-implant nails placed in different locations in the posterior region to improve the hard and soft tissues of the labiodental region in patients with gummy smiles to provide a reference for clinicians.@*Methods@#This study was reviewed and approved by the Ethics Committee, and informed consent was obtained from the patients. Thirty young female patients with anterior tooth protrusions and gummy smiles were included in the retrospective study; 18 patients had micro-implant nails implanted between the premolars (group A), and 12 patients had implant nails placed between the roots of the premolar and the molar and an intraoperatively placed rocking-chair archwire (group B). The preoperative and postoperative distances from the incisal end of the upper mesial incisors to the lower point of the upper lip (U1-Stms), the vertical distance from the incisal end of the upper mesial incisors to the palatal plane (U1-PP), the vertical distance from the point of the alveolar ridge to the palatal plane (Spr-PP), the distance from the incisal end of the upper mesial incisors to the point of the alveolar margin (U1-Spr), and the vertical distance from the point of the proximal middle buccal cusp of the maxillary first molar to the palatal plane of the maxillary first molar (U6-PP) were measured in the cephalometric lateral radiographs of the two groups; additionally, the amount of hard and soft tissues of the upper anterior region exposedduring smiling and the maximum amount of gingiva exposed during smiling were assessed from the smile photograph.@*Results@#After correction, the lip-dentition relationship improved significantly in both groups, with an average reduction of 2.6 mm in U1-Stms, 2.4 mm in U1-PP, 1.4 mm in Spr-PP, and 0.9 mm in U1-Spr in Group A. In group B, the U1-Stms was reduced by an average of 2.3 mm, the U1-PPs by an average of 1.6 mm, the Spr-PPs by 1.4 mm, and the U1-Spr by 0.2 mm. The difference between pre- and postoperative U6-PP in both groups was not significant (P>0.05). Group A had greater ∆U1-PP and ∆U1-Spr changes than group B(P<0.05). There was no difference between the two groups in terms of ∆U1-Stms or ∆Spr-PP (P>0.05). The amount of soft and hard tissue exposed and maximum amount of gingiva exposed in the upper anterior region of the smile were reduced in 30 patients postoperatively, with group A having anaverage reduction of 70.19% of the preoperative amount of soft and hard tissue exposed in the upper anterior region and an average reduction of 24.12% of the preoperative maximum amount of gingiva exposed, and group B having an average reduction of 76.12% of the preoperative amount of hard and soft tissue exposed in the upper anterior region and an average reduction of 31.88% of the preoperative maximum gingiva exposed after the operation. The difference in the ratio between the two groups was not statistically significant (P>0.05).@*Conclusion@#For patients with proptosis and gummy smiles, placing micro-implant nails between the roots of maxillary premolars can effectively lead to retraction and intrusion of anterior teeth to improve the lip-dentition relationship and improve gummy smile, and placing micro-implant nails between the roots of the maxillary second premolar and the first molar together with the use of rocking chair arches can also achieve a good therapeutic effect.
RESUMO
Objective@#To investigate the clinical efficacy of disc repositioning surgery combined with orthodontic treatment in patients with temporomandibular disorder and facial asymmetry.@*Methods@#One patient who underwent disc repositioning surgery combined with orthodontic treatment for temporomandibular joint disorder and facial asymmetry was reported. Preoperatively, the patient had a skewed shape of the opening, mild pressure pain in the right preauricular region with left mandibular deviation, and a mismatch between the width of the upper and lower dental arches. In the arthrosurgery department, bilateral temporomandibular disc replacement and anchorage were performed through a transauricular incision, and an auxiliary splint was worn to stabilize the jaw position for 6 months. In the orthopedic department, maxillary skeletal expansion was used in combination with the multiloop edgewise archwire technique to reconstruct the occlusion after 16 months of orthodontic treatment.@*Results@#The deviation was corrected by wearing an occlusal splint for six months after joint repositioning and anchoring; moreover, the pain symptoms disappeared, and the cone beam CT examination showed that the bilateral temporomandibular joint space was uniformly enlarged, the lower alveolar ridge midline deviated to the right, the posterior regions of the teeth were bilaterally inverted, and the anterior region and the posterior region of the left side were open. The orthodontic treatment matched the width of the upper and lower dental arches and established the cuspal molar neutrality relationship and the normal overjet coverage of the anterior teeth; additionally, the mandibular position was not obviously skewed. A review of the results of the related literature shows that abnormal occlusal relationships, such as mismatched arch width and skewed occlusal plane, can cause adaptive mandibular deviation, which can lead to the occurrence of TMD. Temporomandibular joint disc anchorage with splint treatment can effectively improve maxillofacial deformity in young TMD patients. After the establishment of a stable, physiologically functional disc-condylar relationship, orthodontic treatment is required to remove the interfering factors to rebuild the occlusion, and long-term postoperative review and follow-up are needed.@*Conclusion@#In patients with TMD and mandibular accommodative deviation due to occlusal anomalies, establishing a normal disc-condylar relationship and eliminating occlusal interference through disc repositioning surgery combined with orthodontic treatment can effectively improve facial shape and establish a stable jaw position.