RESUMEN
Asymmetric distraction with different expansions of left and right maxillary parts is a serious complication of surgically assisted rapid maxillary expansion. An individual, highly standardized surgical intervention based on three-dimensional finite element analysis (FEA) is a new method to improve the quality of therapy. We describe a fundamental simulation-based workflow for preoperative evaluation of the osteotomies in a pilot study to achieve symmetry. A CT scan of the skull was used for analysis. Many feasible osteotomy configurations were generated and optimized using Latin hypercube sampling method and FEA choosing an individual osteotomy and maxillary movement. We successfully applied this workflow to 14 patients with symmetrical distraction.
Asunto(s)
Maxilar , Técnica de Expansión Palatina , Humanos , Análisis de Elementos Finitos , Proyectos Piloto , Flujo de Trabajo , Maxilar/diagnóstico por imagen , Maxilar/cirugíaRESUMEN
OBJECTIVES: Surgically assisted rapid maxillary expansion (SARME) is a treatment modality to overcome maxillary constrictions. During the procedure of transverse expansion, unwanted asymmetries can occur. This retrospective study investigates the transverse expansion behavior of the maxilla utilizing a simulation-driven SARME with targeted bone weakening. MATERIALS AND METHODS: Cone beam computer tomographies of 21 patients before (T1) and 4 months after treatment (T2) with simulation-driven SARME combined with a transpalatal distractor (TPD) and targeted bone weakening were superimposed. The movements of the left, right, and frontal segments were evaluated at the modified WALA ridge, mid root level, and at the root tip of all upper teeth. Linear and angular measurements were performed to detect dentoalveolar changes. RESULTS: Dentoalveolar changes were unavoidable, and buccal tipping of the premolars (6.1° ± 5.0°) was significant (p < 0.05). Transverse expansion in premolar region was higher (6.13 ± 4.63mm) than that in the molar region (4.20 ± 4.64mm). Expansion of left and right segments did not differ significantly (p > 0.05). CONCLUSION: Simulation-driven SARME with targeted bone weakening is effective to achieve symmetrical expansion in the transverse plane. CLINICAL RELEVANCE: Simulation-driven targeted bone weakening is a novel method for SARME to achieve symmetric expansion. Dental side effects cannot be prohibited.
Asunto(s)
Maxilar , Técnica de Expansión Palatina , Diente Premolar/cirugía , Tomografía Computarizada de Haz Cónico , Humanos , Maxilar/diagnóstico por imagen , Maxilar/cirugía , Estudios RetrospectivosRESUMEN
Synovial chondromatosis (SC) is a rare metaplastic disease of the larger joints. It is rarely observed in smaller joints, especially in the temporomandibular joint (TMJ). This disease is considered to be metaplastic and shows no malignant tendencies, but can become locally aggressive, erode the cranial base, and even spread intracranially. To date, nine cases of spread into the intracranial space have been reported in the literature; however, the disease remained extradural in all cases. The authors present a review of the literature and report the case of a 70-year-old man with SC of the right TMJ that had eroded the cranial base, reaching the dura mater; a large intracranial mass was not present. The disease was considered to be stage 3 according to Milgram's classification. The patient was treated surgically, the tumour mass was removed, reconstruction of the cranial base was performed using titanium mesh, and the joint was reconstructed with a temporal muscle interposition flap. Diagnostic images and intraoperative photographs are also presented.