Advanced Prosthodontics Lecture Series PDF

Advanced Prosthodontics Lecture Series Clinical try in, confirmation of maxillomandibular records and final tooth arrangement (Complete Dentures) Santvana Vyas DDS Clinical Assistant Professor, Department of Prosthodontics Laboratory Step Before Clinical Try In Goals of Clinical Try In 1. V...

Advanced Prosthodontics Lecture Series Clinical try in, confirmation of maxillomandibular records and final tooth arrangement (Complete Dentures) Santvana Vyas DDS Clinical Assistant Professor, Department of Prosthodontics Laboratory Step Before Clinical Try In Goals of Clinical Try In 1. Verification of Occlusal Plane 2. Verification of Occlusal Vertical Dimension (OVD) 3. Verification of Centric Relation (CR) and Centric Occlusion (CO) 4. Patient Acceptance How do we achieve them? 1. Esthetics 2. Phonetics 3. Occlusion Goal: Verification of Occlusal Plane Verification of Occlusal Plane 1. Parallelism with • Interpupillary line • Ala-tragus line 2. Esthetics 3. Phonetics Interpupillary Line Ala Tragus Line A line running from the inferior border of the ala of the nose to the superior border on the tragus of the ear; it is frequently used, with a third point on the opposing tragus, for the purpose of establishing the ala-tragus plane; ideally the ala-tragus plane is considered to be parallel to the occlusal plane. GPT 9 1. Esthetics Central Incisors and so on 1. Sagittal plane 2. Frontal plane 3. Horizontal plane 4. Repeat the evaluation for different frames Esthetics 1. 2. 3. 4. 5. 6. 7. 8. Tooth shade Dental and facial midline Incisal edge position Incisal display at rest and in function Occlusal cant Gingival display Even negative space on left and right sides (in upper and lower arches) Lip support Esthetics Incisal display at rest Lip support Lip contour & harmony of lower third of the face Esthetics 1. Verification of occlusal plane • Anterior esthetic plane (cant/no cant; too high up/too far down) • Relationship of maxillary and mandibular anterior teeth • Posterior occlusal plane (cant/no cant; too high up/too far down) 2. Verification of OVD • • • • Harmony of lower third of the face Lip contour Skin tone and appearance Changes in the lip as mandible moves from rest to occlusion 3. Patient acceptance Goal: Verification of Vertical Dimension of Occlusion Interocclusal Rest Space • Interocclusal rest distance/interocclusal rest space/freeway space: the difference between the rest vertical dimension and the occlusal vertical dimension. GPT 9 Verification of Vertical Dimension 1. 2. 3. 4. 5. 6. 7. Pre extraction records Using physiologic rest position Esthetics Phonetics Facial dimensions Deglutition Ridges parallel to each other Closest Speaking Space • Closest speaking space: the space between the anterior teeth when the patient is speaking. According to Dr Earl Pound, the space should not be more or less than 1 to 2 mm of clearance between the incisal edges of the teeth when the patient is unconsciously repeating the letter “S.” Silverman termed this speaking centric, which was defined as the closest relationship of the occlusal surfaces and incisal edges of the mandibular teeth to the maxillary teeth during function and rapid speech; this was later called closest speaking level by Silverman and finally the closest speaking space. GPT 9 2. Phonetics Phonetics Sibilants (linguoalveolar sound) : The sibilants are high frequency sounds produced by a stream of air directed through a minimal incisal separation. 2 forms; Surds & Sonants. • Surds - without laryngeal vibration - s/sh/ch - “sixty six, mississippi, church” • Sonants - with laryngeal vibration - z/zh/j 66 sound/ S sound 1. 2. 3. 4. Anteroposterior position of teeth Relationship of U/L anterior teeth Thickness of the anterior denture base Width of the arch Phonetics Fricatives (Labiodental) : A sound made by forcing air out of the mouth through a narrow opening that is made using the lips, teeth or tongue. • “f”, “v” sounds are fricatives. • Centrals touch the wet/dry border of the lower lip. • Fricatives are used to evaluate esthetic plane. • 55 sound Phonetics • Bilabial sound (b,p,m) : assess lip support • Linguodental sound (th) : assess labiolingual position of anterior teeth Phonetics 1. Verification of occlusal (esthetic) plane : Plane too high up, too far down (f, v sound) 2. Verification of OVD (adequate interocclusal space; s sound, m sound) 3. Patient acceptance Can you see the problems? 1. Esthetics? (think of frames) 2. Phonetics? (f,v,s) Did you correct the problems? 1. Esthetics? 2. Phonetics? Goal: Verification of Centric Relation and Occlusion Centric Relation A maxillomandibular relationship, independent of tooth contact, in which the condyles articulate in the anterior-superior position against the posterior slopes of the articular eminences; in this position, the mandible is restricted to a purely rotary movement; from this unstrained, physiologic, maxillomandibular relationship, the patient can make vertical, lateral or protrusive movements; it is a clinically useful, repeatable reference position. GPT 9 Methods to record CR 1. Anterior Jig (Lucia, 1958) 2. Leaf gauge (Long, 1973) 3. Chin point guidance (McCollum 1927) 4. Bilateral manipulation (Kantor 1972; Hobo 1975; Dawson 1989) operator manipulates mandible with upward pressure. Thumb is on chin with downward pressure to seat condyles in the superior position. 5. Muscle seated centric registration (Roth 1981) 6. Swallowing technique (Shanahan, 1955) 3. Occlusion Centric Occlusion The occlusion of opposing teeth when the mandible is in centric relation; this may or may not coincide with the maximal intercuspal position. GPT 9 Centric Occlusion Centric Occlusion Centric Occlusion CR Verification Record Picture Courtesy: Lecture presentation on CD Tryin Ilser Turkyilmaz DMD, PhD Goal : Patient Acceptance Patient Acceptance Patient accepts the tooth shade and esthetics of the denture. Special instructions are considered. Goals of Clinical Try In Achieved 1. Verification of Occlusal Plane 2. Verification of OVD 3. Verification of CR and CO 4. Patient Acceptance Posterior Palatal Seal (PPS) Area 1. Intraorally identify PPS area. 2. Transfer the PPS area on the master cast. 3. Lab will score the marked PPS area on the cast by scraping a groove 1.5-2 mm wide and deep in a tapering manner. References • Zarb, G. Prosthodontic Treatment for Edentulous Patients, 13th Edition • Burnett CA, Clifford TJ J Dent Res 72(6):964-967 June 1993, Closest Speaking Space During the Production of Sibilant Sounds and its Value in Establishing the Vertical Dimension of Occlusion, • Turrell AJ Clinical assessment of vertical dimension, JPD 1972 Sept • Glossary of Prosthodontic terms 9th ed Thank you