62‐year‐old man complete upper and lower removable prostheses Class III skeletal and left‐sided transverse asymmetry of the mandible. Chin deviation without maxillary or lip cant
Intra-orally, class III upper alveolar ridge minimal signs of alveolar bone resorption with adequate height and width. Class II lower alveolar ridge was moderately resorbed.
Panorex left mandibular condyle and ramus were shortened and slightly widened. No evidence of previous trauma or mandibular fractures.
Potential causes of mandibular asymmetries.
Developmental
Hemimandibular elongation
Unknown etiology
Affects the mandible unilaterally
Presents as transverse displacement of the chin point to contralateral side which presents in early adulthood
No vertical asymmetry
The contralateral mandibular molars deviate lingually in attempt to remain in occlusion
Cross‐bite may develop on the unaffected side
Radiographic elongation of the condyle or body of mandible on the affected side
Hemimandibular hyperplasia
Horizontal and vertical enlargement on one side of the mandible which involves the condyle, ramus, and body of the mandible
The condition usually begins in puberty
The maxillary dentition on the affected side will overerupt to compensate for the excessive vertical mandibular growth, which results in a characteristic transverse cant of the maxillary occlusal plane
If the vertical growth is rapid, then dental eruption may not keep pace and a lateral open bite will occur on the affected side
Radiographic elongation of ramus and condylar enlargement can be seen. The lower border of mandible on the affected side is lower than the unaffected side. There is usually increased distance between molar roots and inferior alveolar canal on the affected side. The unaffected side will have normal height
Hemifacial microsomia
Deficiency of hard and soft tissues on one side of the face during embryonic development (congenital disorder)
Chin point displacement is to the affected side
Hypodontia is commonly noted in these patients
Hemifacial hypertrophy
Asymmetry affects the craniofacial soft and hard tissues
Intrauterine pressure can lead to shortening of the sternocleidomastiod muscle leading to mandibular assymetries
Likely genetic contribution
Hemifacial atrophy (Parry–Romberg syndrome)
Uncertain etiology
Atropy of hard and soft tissues on one side of the face leading to mandibular asymmetry
May be accompanied by hyperpigmentation of the skin, seizures, and facial pain
Pathological
Tumors
For example, benign ameloblastoma
Condylar head tumors cause deviation of the mandible to the unaffected side with unilateral condylar enlargement radiographically
Cysts
Dentigerous cysts
Keratocysts
Infection
Dentoalveolar abscess
Sialadenitis
Condylar resorption
May be secondary to juvenile rheumatoid arthritis, steroid therapy, or orthognathic surgery
Unilateral resorption can lead to mandibular asymmetry
Traumatic
Condylar Fractures
During childhood can lead to arrest in growth
Chin point toward affected side
Functional
Mandibular Displacements
Maxillary narrowing can lead to occlusal interferences leading to lateral displacement of the mandible
Diagnosis
Edentate upper class III alveolar ridge, lower class II alveolar ridge.
Class III skeletal discrepancy and unilateral left‐sided transverse mandibular asymmetry.
Treatment options orthognathic surgery. The patient decided the conservative prosthodontic option would be most appropriate for him in this case based on the information provided on the clinic.
Treatment plan:
Upper and lower complete denture construction.
Upper teeth were set up as per the registration rim and based around the midline. Conventional posterior occlusion was set up on the right side. In order to maintain occlusal contact, the posterior teeth on the lower left side were placed lingual to the alveolar ridge in a balanced occlusal scheme (cross‐bite). Anatomical teeth were used rather than a flat occlusal table.
Due to the gum fit anteriorly and the risk of midline fracture of the denture, processing involved the use of high impact acrylic.
Proth: If the patient wants fix prostheis, what are the workup and considerations?