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
The purpose of this paper is to present the rationale for registration of the Seated Condylar Position (SCP)/Centric Relation (CR) position of the condyles.
The purpose of this paper is to present the technique for registration of the Seated Condylar Position (SCP)/Centric Relation (CR) position of the condyles: a two-piece wax bite registration with deprogramming and no ...The purpose of this paper is to present the technique for registration of the Seated Condylar Position (SCP)/Centric Relation (CR) position of the condyles: a two-piece wax bite registration with deprogramming and no mandibular manipulation.展开更多
Dental instrumentation has long provided insight into the mechanism of musculo-skeletal function of the gnathic system. While large population studies associate dental arch displacement （DAD）, especially laterally, ...Dental instrumentation has long provided insight into the mechanism of musculo-skeletal function of the gnathic system. While large population studies associate dental arch displacement （DAD）, especially laterally, with symptoms, mandibular condyle displacement （CD） resulting from DAD has not been targeted as possibly etiologic in the production of common muscle contraction headache （CMCH） and temporo-mandibular dysfunction （TMD）. The objective was to evaluate the three-dimensional nature of DAD and CD between the seated condylar position （SCP） and the intercuspal position （ICP） and to compare results derived from large deprogrammed asymptomatic and symptomatic populations. A total of 1 192 sets of dental casts collected from asymptomatic and symptomatic populations were articulated in the SCP. The initial occlusal contact, DAD, and condylar displacement were evaluated for frequency, direction, and magnitude of displacement between the SCP and ICP. The data revealed significant displacement between the SCP and ICP of the condyles （displaced most frequently inferior （down） and posterior （distal）） and substantially increased frequency and magnitude of displacement of the dental arches （with posterior premature occlusal contacts, increased overjet, decreased overbite, midline differences, and occlusal classification changes） in symptomatic subjects. These discrepancies were statistically significant and clinically significant. The data support the concept of increased DAD and CD with dysfunction. Transverse condylar displacement, commonly presenting with dental cross bite, may be associated with CMCH and TMD. Displacement of the mandibular condyle may be an etiologic factor in CMCH and dysfunction of the temporo-mandibular joint.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The purpose of this paper is to present the rationale for registration of the Seated Condylar Position (SCP)/Centric Relation (CR) position of the condyles.
文摘The purpose of this paper is to present the technique for registration of the Seated Condylar Position (SCP)/Centric Relation (CR) position of the condyles: a two-piece wax bite registration with deprogramming and no mandibular manipulation.
文摘Dental instrumentation has long provided insight into the mechanism of musculo-skeletal function of the gnathic system. While large population studies associate dental arch displacement （DAD）, especially laterally, with symptoms, mandibular condyle displacement （CD） resulting from DAD has not been targeted as possibly etiologic in the production of common muscle contraction headache （CMCH） and temporo-mandibular dysfunction （TMD）. The objective was to evaluate the three-dimensional nature of DAD and CD between the seated condylar position （SCP） and the intercuspal position （ICP） and to compare results derived from large deprogrammed asymptomatic and symptomatic populations. A total of 1 192 sets of dental casts collected from asymptomatic and symptomatic populations were articulated in the SCP. The initial occlusal contact, DAD, and condylar displacement were evaluated for frequency, direction, and magnitude of displacement between the SCP and ICP. The data revealed significant displacement between the SCP and ICP of the condyles （displaced most frequently inferior （down） and posterior （distal）） and substantially increased frequency and magnitude of displacement of the dental arches （with posterior premature occlusal contacts, increased overjet, decreased overbite, midline differences, and occlusal classification changes） in symptomatic subjects. These discrepancies were statistically significant and clinically significant. The data support the concept of increased DAD and CD with dysfunction. Transverse condylar displacement, commonly presenting with dental cross bite, may be associated with CMCH and TMD. Displacement of the mandibular condyle may be an etiologic factor in CMCH and dysfunction of the temporo-mandibular joint.
