of carnauba wax or by adding a paraffin wax with a higher melting point or small amount of resin. Inlay waxes are available in various colours such as deep blue, green, or purple and in various forms such as small pellets or cones or in jars [3].
Lecron Carver
The Lecron carver is a stainless‐steel instrument used for carving tooth morphology on carving wax. It is also used for carving on inlay wax [4].
It has the following parts (Figure 2.2):
1 The knife end
2 The spoon end/excavating end
3 The handle
4 The shank
The Knife End
Cutting Edge
The knife end has a cutting edge or blade which has a curved anterior part (Figure 2.3a). This edge is used for carving bulk wax. This part of the cutting edge also helps in creating concavities (Figure 2.3b) on the wax surface (eg, in creating the concave lingual or palatal outline of the anterior teeth) [5].
Figure 2.1 Rectangular wax block used for carving human dentition.
Figure 2.2 Parts of the Lecron carver.
Figure 2.3 Edges of the knife end of the Lecron carver.
Non‐cutting Edge/Side
The non‐cutting edge/side is used for smoothing wax and creating the slopes of the triangular ridge. Figure 2.4 shows the carving of the mesial slope (2.4a) and distal slope (2.4b) of the mandibular first molar mesiobuccal cusp.
The Spoon End/Excavating End
This end is used in carving lingual or palatal fossae on the crown of anterior teeth and developmental depression on the roots of all teeth (Figure 2.5a–d), by excavating wax [6].
The Handle
This part of the instrument is used to hold the carver (Figure 2.2) [7].
The Shank
The shank connects handle to knife (Figure 2.2). It may be either straight or angled. In carvers the shank is straight [8].
Figure 2.4 Carving the slopes of the triangular ridge using the non‐cutting side of the carver.
Figure 2.5 (a–d) Carving the developmental depression on the root portion using the spoon end of the carver.
Metallic Scale or Ruler
The metallic scale (Figure 2.6) is used to measure the dimension of the carving before and after the carving procedure.
Vernier Caliper
The Vernier caliper (Figure 2.7) is an aid used to measure
1 Diameter of a small spherical/cylindrical body
2 The dimensions of a given regular body of known mass and hence to determine its density
It has a main scale and a sliding Vernier scale and four jaws [8].
Waxing Instruments
Based on their use waxing instruments are classified as wax addition, carving, or burnishing. PKT instruments (Figure 2.8) used for waxing technique were designed by Dr. Peter K. Thomas. PKT no. 1 and no. 2 are used for adding wax. (They can also be used for burnishing.) PKT no. 3 is a burnisher for refining the occlusal anatomy, and PKT nos. 4 and 5 instruments are wax carvers. For larger increments of wax, PKT no. 1 is used; for smaller increments, PKT no. 2 is used. A no. 7 waxing spatula is used for adding large increments of wax, especially for the initial coating. Wax is melted by heating the instrument first near its shank, then touching the wax and quickly reheating the shank [9].
Figure 2.6 Metallic scale with markings in centimetres.
Figure 2.7 Vernier caliper.
Figure 2.8 PKT instruments set.
Instrument Grasps
The modified pen grasp improves the tactile sense. The pads of the thumb and of the index and middle fingers contact the instrument, while the tip of the ring finger (or tips of the ring and little fingers) is placed on the opposing hand to obtain the rest (Figure 2.10a and b) [7].
Figure 2.9 Pen grasp.
Figure 2.10 Modified pen grasp used for holding the instruments.
References