Record Bases/Wax Rims Flashcards
What is the average initial VDO for occulsal wax rims?
- 44mm from upper/lower labial sulci adjacent ot the labial frenula when teeth are in occlusion
- upper sulcus to incisal edge of the upper central incisor is 22mm
- lower sulcus to incisal edge of the lower central incisor is 18 mm
What is the point of the record base?
An interim denture base used to support the record rim material for recording maxillomandibular records
What are interim record bases?
discarded during denture processing (resin, triad)
What are permanent record bases?
actually become part of the completed denture (processed resin, metal)
What is the trial base?
a material or device representing the base of a denture. It is used for making maxillomandibular relationship records and for the arrangement of teeth
What is the postpalatal seal area?
the soft tissue area at or beyond the junction of the hard or soft palates on which pressure, within physiologic limits can be applied by a denture to aid in its retention
What is the postpalatal seal?
the seal area at the posterior border of a maxillary prosthesis
How do you establish a postpalatal seal?
- Locate vibrating line in mouth by palpating hamular notches with mirror.
- Have pnt. say “AH” and mark the area where the soft palate flexes upward.
- Mark “vibrating line” with indelible pencil.
- Transfer the marked posterior palatal seal line from the mouth to the final impression.
- Carve the transferred posterior palatal seal into the master cast before making the recored base.
What are the different record base fabrication materials?
- autopolymerized resin
- visible-light-cured material
- vacuum formed
- heat-processed resin
- cast metal
What are the roles of the record bases/wax rims?
Establish Rest Vertical Dimension
Establish Occlusal Vertical Dimension
Establish adequate interocc. Distance
Establish tentative occlusal plane
Determine & record centric relation
Transfer jaw relationship to articulator
Enable “Trial denture” arrangement
What must the record bases be…
- rigid
- stable
- smooth, contoured, comfortable
- accurately fitting for retention and stability
What are the most common mistakes with record bases/wax rims?
Improper Occ. Vert. Dimension
Inaccurate centric relation registration
Unstable “Trial Denture” (renders phonetic tests and esthetic assessments inaccurate)
Decreased patient confidence in dentist
What is the purpose of the wax occlusion rims?
- serve as means of transfer of face bow
- aid in orientation of the incisors and occusal plane
- aid in developing contours of the lips/cheeks
- used in developing the vertical dimension
- used in making tentatie centric relation records
- serve as a general aid in selection of teeth
What is a wax occlusion rim?
an analogue for the mouth’s neutral zone
What is an ala tragus line?
a line running form the inferior border of the ala of the nose to some defined point on the tragus of the ear, usually considered to be the tip of the tragus.
