Transcript
Pontics
Preeti kaliaIInd year PG student
Dept of ProsthodonticsA.E.C.S Maaruti College of Dental
Sciences
Pontics
Definition
Requirements
Design
Pretreatments assessment
Types
Fabrication
Definition
Pontic GPT : An artificial tooth on a fixed dental prosthesis that replaces a missing natural tooth, restores its function, and usually fills the space previously occupied by the clinical crown
Definition
Acc to Tylman –pontic is the suspended member of a fixed partial denture. it replaces the lost natural tooth, restores function ,and occupies the space of the missing tooth.
Ideal requirements of pontics
Smooth surfaced and convex in all directions
Easily cleansable
Pinpoint pressure free contact on the ridge
No irritation to the gingival tissues
Ideal requirement of pontics
Facilitate plaque control
Emergence profile
Strength and longevity
Be esthetic
Ideal requirements of pontics
Restore function
No abutment overloading
Color stable
Functions of pontics
Mastication
Speech
Esthetics
Considerations for a successful pontic design
Biologic considerations
Ridge contact Area of contact
with ridge should be small and convex.
Oral hygiene considerations
Pontic materials
Differences in the plaque-retaining capacities of.samples of a Type III gold, gold for veneering with porcelain, a vacuum-fired
bonded porcelain Veneer, and an acrylic resin.
After 48 hours in vivo, the Ceramco metal and Type III gold specimens accumulated significantly more dark stains than acrylic ones
Wise. M et al and Dykema .R, The plaque-retaining capacity of four dental materials,J Proshtet 1975;33:178
Occlusal forces
Reduce buccolingual width – 30% to lessen occlusal forces
12% increase in chewing efficiency Pontics with normal occlusal widths
– in the occlusal third area
Mechanical considerations
Improper choice of materials Poor framework design Poor tooth preparation Poor occlusion
It can be seen that the maximum tensile stress at the solder joint, mesial to the second molar and above the gingiva, was reduced from2,400 p.s.i, in the conventional pontic to 1,200 p.s.i, in the sanitary pontic and finally to 720 p.s.i, in the modified sanitary pontic.
For the solder joint distal to the second
premolar, also above till gingiva, the reductions were in the order of 1,920 (C.P.)to 960 (S.P.) to 720 p.s.i. (M.S.P.).
Hood, J. A. Stress and deflection of three different pontic designs. J Prosthet Dent 33:54-59, 1975
Esthetic considerations
Incisogingival length
Root can be stained to simulate exposed dentine.
Pink porcelain to simulate the gingival tissues
Mesiodistal width
Space discrepancy – less problem in posteriors
Mesiodistal width
Orthodontic treatment Pontic of abnormal size- illusion of natural tooth
Pretreatment assessment
Diagnostic cast Wax up
Pontic space
Individual crowns of increased proximal contours were preferredto an FPD with undersized pontics
Residual ridge contour
Loss of residual ridge contour leading tounesthetic open gingival embrasures
Food entrapment
Residual ridge contour
Class II defect.Class I defect.
Class III defect.
Sieberts classification
Residual ridge contour
Abrams et al showed Class I defects to constitute 32.4%Class II- 2.9% Class III- 55.9% 8.8% having no defects
Surgical management of class I defect
Pouch technique
Surgical management of class I defect
Pouch technique
Surgical management of class II and III defect
Interpostional graft
Surgical management of class II and III defect
onlay graft
Gingival architecture preservation
Classification
1. Depending on shape of surface contacting the ridge(Tylmann)
Sanitary Modified sanitary Spheroidal Saddle Ridge lap Modified ridgelap Ovate
2.According to Rosenstiel depending on mucosal contact A. mucosal contact ridge lap modified ridge lap ovate conical B. No mucosal contact sanitary(hygenic) modified sanitary
3.According to the form(Johnston)
Sanitary or Hygenic
Anatomic type
4.Based on materials used Metal Metal and porcelain Metal and resin
5.Prefabricated pontics
Flat back Trupontic
Longpinfacing
Pontips
Reverse pin facings
Sanitary or hygienic
Modified sanitary pontic
Ridge lap pontic
Modified ridge lap pontic
Conical pontic
Ovate pontic
Modified ovate pontic
Contact more labially than ovate pontic Easier to clean No need of surgical augmentation Push the labial gingival margin away
to floss
Liu.S,J Esthet Restor Dent 16:273-283, 2004
Residual ridge contour To determine the frequency and the
nature of tissue reactions of underlying residual ridge mucosa to specific pontic designs, and
To compare the frequency and the nature of tissue reactions of residual ridge mucosa to various materials used in pontic construction.
Stein.R.S , Pontic residual ridge relationship, J Proshtet Dent 1966;16: 251-285
Metal Ceramic pontics Uniform veneer of porcelain- 1.2 mm Metal surface – smooth and free of pits Round angles Occlusal centric contacts – 1.5 mm away from junction
Metal ceramic pontics
wax the prosthesis
All ceramic pontics
Resin veneered pontics
Fiber reinforced composite resin pontics
Pontic fabrication
All metal hygienic pontic Metal ceramic pontic
Armamentarium
Sable brush Plaster bowl Spatula Quick setting plaster Bunsen burner PKT waxing instruments- No
1,2,3,4,5 Beavertail burnisher No 7 wax spatula Inlay casting wax Die lubricant Cotton pliers Hollow plastic sprue
All metal hygienic pontic fabrication
All metal hygienic pontic fabrication
All metal hygienic pontic fabrication
All metal hygienic pontic fabrication
All metal hygienic pontic fabrication
Metal ceramic pontics
Requirements Adequate bulk of
metal Uniform
thickness of porcelain
Continuous strip of metal on lingual surface
Scalloped or trestle design
Connector is diminished in faciolingual dimension – Indication
Bulk or rigidity in connector areas Tissue contact – modified ridge lap
Metal ceramic pontics
To produce continuous contour and uniform thickness of porcelain – fabricate wax pattern to full contour and cut back
Fabricate the copings – No 7 wax spatula
Blue inlay wax stick – edentulous area
Metal ceramic pontics
Check the alignment in a mesiodistal and the facial profile
Metal ceramic pontics
Metal ceramic pontics
Available pontic systemsAdvantages Disadvantag
esIndications Contraindicatio
ns
Metal ceramic
EstheticsBiocompatible
Difficult if abutment not metal ceramic
Most situations
Long span with high stress
All metal StrengthStraightforward procedure
Non esthetic Mandibular molars, under high bite force
Esthetics
Fibre reinforced all resin
Conservative with inlaysEsthetics
Limited to short spans
Esthetics Long span
Facings Rarely used Rarely used Rarely used
Rarely used
Review of literature
Kumbulolu.O et al, A Different Pontic Design for Fiber-Reinforced Composite Bridgeworks: A Clinical Report, Eur J Dent. 2007 January; 1(1): 50–53.
Review of literature
Kim.T.H.Yet al, Simulated tissue using unique pontic design, J Prosthet Dent 2009;102:205-210
References
Malone W.F.P., Koth D.L., Cavazos E. : Tylman’s theory of practice of fixed prosthodontics. 8 Ed., lshiyaku publications, 1993,357-370
Rosenstiel R.F., Land M.F., Fujimot J.: Contemporary fixed prosthodontics. 4th Ed., Mosby Publications, 2007, 616-648
References
Shillingburg H.T., Hobo S., Whisett L.D., Jacobi R., Brackett S.E. Fundamentals of fixed prosthodontics, 3 Ed., Quintessence Publication,2007,India ,485-506
Stein.R.S , Pontic residual ridge relationship, J Proshtet Dent 1966;16: 251-285
References
Wise. M et al and Dykema .R, The plaque-retaining capacity of four dental materials,J Proshtet 1975;33:178
Liu.S ,Use of a modified ovate pontic in areas of ridge defects: A report of 2 cases, J Esthet Restor Dent 16:273-283, 2004
References
Kumbulolu.O et al, A Different Pontic Design for Fiber-Reinforced Composite
Bridgeworks: A Clinical Report, Eur J Dent. 2007 January; 1(1): 50–53.
Kim.T.H.Yet al, Simulated tissue using unique pontic design, J Prosthet Dent 2009;102:205-210
References
R.Duane Douglas ,Pontic design
FPDpontic wax up .ppt
FPD.ppt
top related