Prostho (CD)

Diagnostic Criteria (Thomas McGarry ACP Classification) of Complete Denture Patients The diagnostic criteria are organized by their objective nature and not in the sequence of significance. Certain criteria even are more significant than others. However,the following objective criteria allow the most accurate application of the classification system.43 8.A 7. Bone Heights (Mandible) The continued decrease in bone volume affects: • Denture-bearing area; • Tissues remaining for reconstruction; • Facial muscle support/attachment; • Total facial height; and • Ridge morphology. In order to minimise variability in radiographic techniques, the measurement should be made on the radiograph at that portion of the mandible of the least vertical height. A measurement is made and the patient is classified as follows: 21 mm or greater measured at the least vertical height of the mandible Type II: Residual bone height of 16 to 20 mm measured at the least vertical height of the mandible Type III: Residual alveolar bone height of 11 to 15 mm measured at the least vertical height of the mandible Type IV: Residual vertical bone height of 10 mm or less measured at the least vertical height of the mandible. 8.A.2. Residual Ridge Morphology (Maxilla) Residual ridge morphology is the most objective criterion for the maxilla because measurement of the maxillary residual bone height by radiography is not reliable. The classification system continues on a logical progression, describing the effects of residual ridge morphology and the influence of musculature on a maxillary denture. Type A (most favorable): • Anterior labial and posterior buccal vestibular depth that resists vertical and horizontal movements of the denture base. • Palatal morphology resists vertical and horizontal movement of the denture base. • Sufficient tuberosity definition to resist vertical and horizontal movement of the denture base. • Hamular notch is well defined to establish the posterior extension of the denture base. • Absence of tori or exostoses. Type B: Loss of posterior buccal vestibule. Palatal vault morphology that resists vertical and horizontal movements of the denture base. Tuberosity and hamular notch are poorly defined, compromising delineation of the posterior extension of the denture base. Maxillary palatal tori and/or lateral exostoses are rounded and do not affect the posterior extension of the denture base. Type C: Loss of anterior labial vestibule. Palatal vault morphology offers minimal resistance to vertical and horizontal movements of the denture base. Maxillary palatal tori and/or lateral exostoses with bony undercuts that do not affect the posterior extension of the denture base. Hyperplastic, mobile anterior ridge offers minimum support and stability of the denture base. Reduction of the postmalar space by the coronoid process during mandibular opening and/or excursive movements. 45

See Further

Classification System for Complete Edentulism

Class I, II,or III maxillomandibular relationship. • Limited interarch space( 18-20 mm). • Moderate psychosocial considerations and /or moderate oral manifestations of systemic diseases or conditions, such as xerostomia.

Class I

This classification levelcharacterizes the stage ofedentulism that is most apt to be successfully treated with complete dentures using conventional prosthodontic techniques.

All four of the diagnostic criteria are favorable. • Residual bone height of 21 mm or greater measured at theleast vertical height ofthe mandible ona panoramic radiograph. • Residual ridge morphology resists horizontal and vertical movements of the denture base;Type A maxilla. • Location of muscle attachments that are conducive to denture base stability and retention. • Type A orB mandible. • Class Imaxillomandibular relationship. Class II This classification level distinguishes itself by the continued physical degradation of the denturesupporting anatomy, and, in addition, is characterized by the early onset of systemic disease interactions, patient management, and/or lifestyle considerations. • Residual bone height of 16 to 20 mm measured at the least vertical height of the mandible on a panoramic radiograph. • Residual ridge morphology that resists horizontal and vertical movements of the denture base; Type A or B maxilla. • Location of muscle attachments with limited influence on denture base stability and retention; Type A or B mandible. • Class I maxillomandibular relationship. • Minor modifiers, psychosocial considerations, systemic disease with oral manifestation. mild • TMD symptoms present. • Large tongue (occludes interdental space) with or without hyperactivity. • Hyperactive gag. Class III This classification level is characterized by the need for surgical revision of supporting structures to allow for adequate prosthodontic function. Additional factors now play a significant role in treatment outcomes. • Residual alveolar bone height of 11 to 15 mm measured at the least vertical height of the mandible on a panoramic radiograph. • Residual ridge morphology has minimum influence to resist horizontal or vertical movement of the denture base;Type C maxilla. 48 • Location of muscle attachments with moderate influence on denture base stability and retention;Type C mandible. • Conditions requiring preprosthetic surgery: (1) Minor soft tissue procedures; ( 2) Minor hard tissue procedures including alveoloplasty; (3) Simpleimplant placement,noaugmentationrequired; (4) Multiple extractions leading to complete edentulism for immediate denture placement. Class IV This classification level depicts the most debilitated edentulous condition. Surgical reconstruction is almost always indicated but cannot always be accomplished because of the patient's health, preferences, dental history,and financial considerations. When surgical revision is not an option, prosthodontic techniques of a specialized nature must be used to achieve an adequate treatment outcome. • Residual vertical bone height of 10 mmor less measured at the least vertical height of the mandible on a panoramic radiograph. • Residual ridge offers no resistance to horizontal or vertical movement. • Type D maxilla. • Muscle attachment location that can be expected to have significant influence on denture base stability and retention;Type D orE mandible. • Class I, ll,or III maxillomandibular relationships. • Major conditions requiring preprosthetic surgery: (1) Complex implant placement,augmentation required; (2) Surgical correction of dentofacial deformities; (3) Hard tissue augmentation required; (4) Major soft tissue revision required, i.e., vestibular extensions with or without soft tissue grafting. • History of parasthesia or dysesthesia. • Insufficient interarch space with surgical correction required. • Acquired or congenital maxillofacial defects. Severe oral manifestation of systemic disease or conditions, such as sequelae from oncological treatment. • Maxillomandibular ataxia (incoordination). Hyperactivity of tongue that can be associated witha retracted tongue position and/or its associated morphology. • Hyperactive gag reflex managed with medication. Refractory patient (a patient who presents with chronic complaints following appropriate therapy). These patients may continue to have difficulty achieving their treatment expectations despite the thoroughness or frequency of the treatments provided. • Psychosocial conditions warranting professional intervention.