BACKGROUND Temporomandibular joint(TMJ)disorders are closely related to high-angle and skeletal Class II malocclusion.Sometimes pathological changes in the mandibular condyle can cause open bite to occur after growth ...BACKGROUND Temporomandibular joint(TMJ)disorders are closely related to high-angle and skeletal Class II malocclusion.Sometimes pathological changes in the mandibular condyle can cause open bite to occur after growth is complete.CASE SUMMARY This article is about the treatment of an adult male patient with a severe hyperdivergent skeletal Class II base,an unusual and gradually occurring open bite and an abnormal mandibular condyle anterior displacement.Because the patient refused surgery,four second molars with cavities and root canal therapy were extracted,and four mini-screws were used for intrusion of the posterior teeth.The treatment duration was 22 mo,and after the treatment,the open bite was corrected and the displaced mandibular condyles were seated back to the articular fossa as shown by cone-beam computed tomography(CBCT).Based on the patient’s open bite history,the result of clinical examinations and CBCT comparisons,we believe it is possible that the occlusion interference was eliminated after the four second molars were extracted and the posterior teeth were intruded,and the patient's condyle spontaneously returned to its physiologic position.Finally,a normal overbite was established,and stable occlusion was achieved.CONCLUSION This case report suggested that identifying the cause of open bite is essential,and the TMJ factors for hyperdivergent skeletal Class II cases should be particularly examined.For these cases,intruding posterior teeth may place the condyle in a more appropriate position and provide an environment suitable for TMJ recovery.展开更多
Introduction: One of the most common risks of fixed orthodontic therapy is the evidence of root resorption post orthodontic treatment ranging from mild root blunting to severe root resorption of significant portions o...Introduction: One of the most common risks of fixed orthodontic therapy is the evidence of root resorption post orthodontic treatment ranging from mild root blunting to severe root resorption of significant portions of the root structure. The etiology of apical root resorption is multifactorial but largely depends upon the type of orthodontic tooth movement and treatment duration. Study Objective: The primary aim of this study is to examine the association of external apical root resorption and vertical correction in anterior open bite malocclusions using panoramic radiographs for evaluation. Materials and Methods: Pre-treatment and post-treatment panoramic radiographs of 16 patients with anterior open bite malocclusions were scored to assess root resorption of anterior teeth (U/L 3-3). Initial and final root length and total tooth length for U/L 3-3 were measured on panoramic radiographs in Dolphin imaging. Results: Of the 24 pairs of measurements, 7 had a significant p-value (p Conclusions: A statistically significant amount of root resorption was observed, from pre-treatment to post-treatment radiographs. All mandibular anterior teeth except the mandibular right lateral incisors showed evidence of root resorption.展开更多
Supernumerary marker chromosome 15 （sSMC[15]） is the most frequent marker chromosome, and it is generally regarded as unimportant if it does not contain the Prader-Willi/Angelman syndrome critical region （PWACR）. ...Supernumerary marker chromosome 15 （sSMC[15]） is the most frequent marker chromosome, and it is generally regarded as unimportant if it does not contain the Prader-Willi/Angelman syndrome critical region （PWACR）. The clinical importance of the larger markers in association with the critical region is mentioned in almost all reports related to marker chromosome 15, and smaller markers are solely associated with minor dysmorphic features, azoospermia and recurrent miscarriages. However, these small sSMC（15）s without the PWACR may also determine a specific phenotype. A dysmorphic examination of an azoospermic patient in a genetics clinic was performed and was followed by a peripheral blood lymphocyte chromosomal analysis according to standard cytogenetic methods. Nucleolar region （NOR） banding, C-banding, fluorescence in situ hybridization and a molecular investigation of Y-microdeletions were also performed. The clinical evaluation identified dysmorphic features accompanied with azoospermia and severe ‘Angle Class Ⅱ, Division 1 Open Bite Deformity＇. The molecular cytogenetic study revealed the small sSMC（15）. In addition, a Y-microdeletion analysis showed that the azoospermia was not the result of a deletion. Although the presented case might represent a coincidental example of supernumerary marker 15 and mandibular anomaly association, the condition may also define a specific phenotype that may be more than azoospermia. This condition may be characterized by infertility, malar hypoplasia, mandibular anomaly, keloid formation and minor dysmorphic features.展开更多
文摘BACKGROUND Temporomandibular joint(TMJ)disorders are closely related to high-angle and skeletal Class II malocclusion.Sometimes pathological changes in the mandibular condyle can cause open bite to occur after growth is complete.CASE SUMMARY This article is about the treatment of an adult male patient with a severe hyperdivergent skeletal Class II base,an unusual and gradually occurring open bite and an abnormal mandibular condyle anterior displacement.Because the patient refused surgery,four second molars with cavities and root canal therapy were extracted,and four mini-screws were used for intrusion of the posterior teeth.The treatment duration was 22 mo,and after the treatment,the open bite was corrected and the displaced mandibular condyles were seated back to the articular fossa as shown by cone-beam computed tomography(CBCT).Based on the patient’s open bite history,the result of clinical examinations and CBCT comparisons,we believe it is possible that the occlusion interference was eliminated after the four second molars were extracted and the posterior teeth were intruded,and the patient's condyle spontaneously returned to its physiologic position.Finally,a normal overbite was established,and stable occlusion was achieved.CONCLUSION This case report suggested that identifying the cause of open bite is essential,and the TMJ factors for hyperdivergent skeletal Class II cases should be particularly examined.For these cases,intruding posterior teeth may place the condyle in a more appropriate position and provide an environment suitable for TMJ recovery.
文摘Introduction: One of the most common risks of fixed orthodontic therapy is the evidence of root resorption post orthodontic treatment ranging from mild root blunting to severe root resorption of significant portions of the root structure. The etiology of apical root resorption is multifactorial but largely depends upon the type of orthodontic tooth movement and treatment duration. Study Objective: The primary aim of this study is to examine the association of external apical root resorption and vertical correction in anterior open bite malocclusions using panoramic radiographs for evaluation. Materials and Methods: Pre-treatment and post-treatment panoramic radiographs of 16 patients with anterior open bite malocclusions were scored to assess root resorption of anterior teeth (U/L 3-3). Initial and final root length and total tooth length for U/L 3-3 were measured on panoramic radiographs in Dolphin imaging. Results: Of the 24 pairs of measurements, 7 had a significant p-value (p Conclusions: A statistically significant amount of root resorption was observed, from pre-treatment to post-treatment radiographs. All mandibular anterior teeth except the mandibular right lateral incisors showed evidence of root resorption.
文摘Supernumerary marker chromosome 15 （sSMC[15]） is the most frequent marker chromosome, and it is generally regarded as unimportant if it does not contain the Prader-Willi/Angelman syndrome critical region （PWACR）. The clinical importance of the larger markers in association with the critical region is mentioned in almost all reports related to marker chromosome 15, and smaller markers are solely associated with minor dysmorphic features, azoospermia and recurrent miscarriages. However, these small sSMC（15）s without the PWACR may also determine a specific phenotype. A dysmorphic examination of an azoospermic patient in a genetics clinic was performed and was followed by a peripheral blood lymphocyte chromosomal analysis according to standard cytogenetic methods. Nucleolar region （NOR） banding, C-banding, fluorescence in situ hybridization and a molecular investigation of Y-microdeletions were also performed. The clinical evaluation identified dysmorphic features accompanied with azoospermia and severe ‘Angle Class Ⅱ, Division 1 Open Bite Deformity＇. The molecular cytogenetic study revealed the small sSMC（15）. In addition, a Y-microdeletion analysis showed that the azoospermia was not the result of a deletion. Although the presented case might represent a coincidental example of supernumerary marker 15 and mandibular anomaly association, the condition may also define a specific phenotype that may be more than azoospermia. This condition may be characterized by infertility, malar hypoplasia, mandibular anomaly, keloid formation and minor dysmorphic features.
