TYPES OF CARVER

They are used for carving amalgam and resin composites

TYPES

Large discoid - cleoid

Small discoid - cleoid

No.14 sickel shaped carver

Hollenback no. ½ caver

Frahms 90 degree carver

Walls no.3

Interproximal carver

Wards carver

Scalpel blade no. 12 mounted on scalpel handle

• Cleoid-discoid - for carving occlusal surface in molar and useful for lingual concavities in anterior teeth

• Walls no.3 – for carving occlusal surface,the end that is shaped like hoe is used for shaping cusps & for carving lingual and facial surfaces

• Hollenback – used for occlusal,proximal,axial surfaces
  

• Interproxiaml – have very thin blades for carving proximal amalgam surface

• Scalpel blade No. 12 - is used for carving resin composite restorations

• Sickel No.14L – For carving interproximal areas.It has very strong hollow round triangular blade – to remove amalgam over hangs.
  

• Wards carver - for occlusal surface and carving proximal surface in class IIrestoration.

• Frahm's 90 degree carver(diamond carver) - for carving occlusal surface.

FLUORIDE RELEASE AND RECHARGE OF DIFFERENT MATERIALS

GLASS IONOMER

The releasing and recharge ability of the material fully depends on the glass particle,particularly the amount of hydrogel layer over glass filler.

In case of glass ionomer the powder liquid reaction is acid base reaction and the reaction results in more well defined amount of hydrogel matrix over the glass particle.

So that glass ionomer release large amount of fluoride initially(hydrogel matrix) and release reduces with time, at the same time the released fluoride is recharged with exernal fluoride source such as fluoride solution,fluoride varnish,fluoride tooth paste.fluoride mouthrinse.

The initial "burst" effect is only seen in glass ionomer,compomer and giomer does on exibit initial "burst".


COMPOMER
In Compomer, polyacrylic acid and resin matrix combined into one molecule.

Initially polymerization reaction takes place followed by subsequent sorption of water leads to ionization of acid and acid base reaction takes place at the slow rate.The fluoride release is during first sevan days in expected to be low.

The acid base reaction is less prominent in this case and hydrogel layer formed in small part.

In Compomer fluoride release is less when compared to glass ionomer and the recharging ability is not seen case of compomer.

GIOMER
In Giomer the fluoride release is similar to that of glass ionomer,the difference of giomer from compomer in fluoride release is both contain glass ionomer and resin matrix but in case of giomer the glass particles are pre-reacted with polyacrylic acid before blending with resin matrix.

The hydrogel layer is more extensive in giomer similar to that of glass ionomer.

Fluoride release in case of giomer is by exchange mechanism in the direction of lower fluoride concentration from higher concentration.The existence of a CONCENTRATION GRADIENT is the driving force for fluoride release.

Fluoride release of giomer was greaer than other materials at day sevan and it became significantly lower at day due to diminishing fluoride gradient

REFERENCES
Giomer restorations,Dental Abstracts
Volume 50, Issue 6, November-December 2005, Page 355

A three-year clinical evaluation of two dentin bonding agents
J Am Dent Assoc, Vol 135, No 4, 451-457
BRUCE A. MATIS, D.D.S., M.S.D., MICHAEL J. COCHRAN, D.D.S., M.S.D.,

Evaluation of a self-etching primer and a giomer restorative material: Results at eight years
J Am Dent Assoc 2007;138;621-627
Valeria V. Gordan, Eduardo Mondragon, Ronald

Surface Finish of a New Hybrid Aesthetic Restorative Material
Operative Dentistry, 2002, 27, 161-166
AUJ Yap • BYY Mok

Short-Term Fluoride Release from Various Aesthetic Restorative Materials
Operative Dentistry, 2002, 27, 259-265,AUJ Yap • SY Tham,LY Zhu • HK Lee

Fluoride release and recharge in giomer,compomer and resin composite
Dental Materials (2004) 20, 789–795
Toshiyuki Itotaa,b, Thomas E. Carricka, Masahiro Yoshiyamab,John F. McCabea

Clinical evaluation of two one-bottle dentin adhesives at three years ,
J Am Dent Assoc, Vol 132, No 8, 1117-1123
EDWARD J. SWIFT JR., D.M.D., M.S., JORGE PERDIGÃO, D.D.S., M.S., PH.D.,

GIOMER

GIOMER is basically a modified GLASS IONOMER.

It is a true hybrid of two compounds, Glass Ionomer and Composite

The difference of Giomer from Compomer is, in Compomer variable amount of unhydrated polyacrylic acid is added to the resin matrix and the acid base reaction wont takes place until water comes and contact with compomer

The main disadvantage of COMPOMER is less amount of Fluoride release and absence of Fluoride recharging ability.This makes the GIOMER more preferable then compomer

GIOMER uses PRG( Pre Reacted Glass ionomer ) TECHNOLOGY by which it differs from compomer, in giomer the glass filler particles used are pre reacted with polyacrylic acid

By using this technology,we can get the properties of both glass ionomer and composites.

The properties of GIOMER is fluoride release and fluoride recharging of glass ionomer and esthetics,easy of polishing,and strength of composite.

COMPOSITION Of GIOMER (BEAUTIFUL)

• Bisphenol A glycidyl dimethacrylate,
• TEGDMA,
• inorganic glass filler,
• aluminuoxide, silica,
• pre-reacted glass ionomer filler,
• DL-camphorquinone

PRG TECHNOLOGY IN GIOMER

There is a pre reaction of Fluoroalumino silicate glass fillers with Polyacrylic acid,the reaction produce a glass ionomer which is more stable

This phase is called”WET SILICEOUS HYDROGEL”

This material is freeze dried, milled, treated with silane and then round to produce PRG fillers, then these glass fillers are added to the resin matrix(GIOMER)

PRG TECHNOLOGY is used in production of two types of fillers.

They are:
S-PRG (Surface Pre Reacted Glass Ionomer) marketed as BEAUTIFUL (shofu)

F-PRG (Full Pre Reacted Glass Ionomer) marketed as REACTMER (shofu)

GOD'S GRACE