Chapter 30 Pediatric Dental Procedures
Parents are more concerned about esthetics than ever before. In the past, parents accepted whatever restoration the dentist used, whether it was dental amalgam or stainless steel crowns. Those are still used in pediatric dentistry, but parents are asking more and more that the dentist incorporate an esthetically desirable approach into the restorative dentistry or other procedures. It may be an extension of the phenomenon in society that everything is about esthetics, perhaps as a result of the consumer marketing world or the professional world of dentistry. In pediatric dentistry, parents are typically young and often have had whitening or veneers. The difference between adult dentistry and pediatric dentistry with regard to esthetics is that pediatric patients are rarely brought in specifically for esthetic purposes. Esthetics is an added part of restoration fairly exclusively, whereas in adult dentistry esthetics is often the primary objective.
If a child loses the primary maxillary incisors prematurely, that is, before the permanent successors are erupted, he or she can have 2 or 3 years during which there is a space. The child might be made fun of in school or other social situations. Many studies show that children with crowded teeth may have low self-esteem.1,2 A main cause of crowding in the permanent dentition is space lost in the primary dentition because orthodontic treatment was not performed. If the skeletal causes of orthodontic problems are excluded, crowding in the permanent dentition most often results from the early loss of primary teeth through decay or infections. Space may also be lost without loss of the tooth when an interproximal caries lesion remains untreated. Clearly the primary dentition can have an effect on the permanent dentition and can potentially damage the child’s self-esteem.
Esthetically desirable procedures for children have undergone a continuous development process. Twenty or 30 years ago there were few choices of procedures or materials. Before command-cure resin composites were available, using a self-cured composite in a moving, young child was very challenging. Light-cured composites have been extremely important in pediatric dentistry. Stainless steel crowns have been a mainstay and still are used for primary molars when the decay extends beyond ideal size for a composite restoration. Amalgams have not stood the test of time well, whereas stainless steel crowns have. The convergence of the primary molar toward the occlusal surface anatomically makes it more challenging to perform an intracoronal restoration. The permanent counterparts, stainless steel crowns, have been around and are still used, but, as noted, parents are asking for esthetically desirable alternatives. The clinicians have responded by trying to create window facings on stainless steel crowns or to place composite resin (strip) crowns. Other substitutes for stainless steel crowns are more esthetically desirable prefabricated veneered stainless steel crowns.
The greatest area of challenge in primary anterior teeth is the degree of surface decay present. Typically, interproximal and lingual decay sites are found in early childhood caries, formerly termed nursing bottle decay. Restoring these teeth esthetically with composite is a significant challenge for pediatric dentists because these lesions are mostly close to the pulp and may extend subgingivally. It is necessary to determine the pulp’s status before the tooth is restored. If the pulp is involved in the preparation, with or without disease, pulpectomy should be included in the treatment plan. The diameter of the crown mesio-distally is greater than the length cervico-incisally, which makes the tooth appear wider. The retention of the restoration is compromised by the short crown length.
First, a radiograph is obtained to find out if the decay is close to the pulp. Second, the history is carefully reviewed with the parents. The diagnosis is based on the information obtained from the history, the dental radiographs, and the soft tissue examination. The visual and tactile examinations are very important. The dentist may not be able to see a sinus tract, but careful palpation can sometimes reveal small craters on the labial side, indicating that the pulp is involved.
Resin composite crowns are the most esthetically desirable anterior restorations for primary anterior teeth but are also among the most technique-sensitive procedures. With crowding of the anterior teeth, it is quite challenging to perform a direct composite restoration. Also, primary teeth are whiter than permanent teeth. Most of the time, shade A1 or Extra White must be used. If in doubt, a tab of composite can be placed on the tooth and light cured to account for the shade changes occurring during polymerization. Once the proper shade has been selected, the process continues using that composite. Figure 30-1 presents an example of adhesively bonded resin composite (strip) crowns.
FIGURE 30-1 Resin composite (strip) crowns. A, Clinical photograph shows extensive caries lesions and white spot lesions on all four incisors. Left untreated, these lesions will develop into larger lesions and possibly affect the adjacent teeth and the underlying permanent successors. B, Palatal view. Caries lesions are found in all the interproximal areas of the incisors. Wear facets are seen on the lingual aspect close to the gingival line. These wear facets result from the grinding of teeth, which is very common in primary teeth. C, Rubber dam isolation technique. Dental floss is used to secure the elastic rings. The procedure is performed using general anesthesia. Decayed areas are removed and the area restored. In this case, the lingual surface was prepared and tooth reduction was performed mainly on the facial and interproximal surfaces. The pulp was not exposed in these four incisors after complete removal of decay. D, Immediate post-treatment photograph shows gingival bleeding from the sulcus. E, Post-treatment photograph shows a slightly open bite. In restoring the case, the bite was intentionally opened slightly to eliminate the wear on the lingual facets of the maxillary anterior teeth.
Preparation design for primary anterior teeth is different from what is needed for permanent anterior teeth because the teeth are small and more amenable to good esthetically desirable results. There should be sufficient incisal reduction (about 1.5 mm) to avoid incisal fracture. In the preferred design, more reduction on the labial surface is required. A small undercut on the facial surface in the gingival third of the tooth is recommended to serve as a mechanical lock. On the lingual surface there is often minimal reduction (about 0.5 mm) and a feather-edged gingival margin.
Because placing composite is so technique sensitive, it is necessary to use rubber dam isolation to achieve a good result. Many isolation techniques have been used by clinicians. Traditionally the most popular techniques are the use of ligature ties with dental floss to retract the gingival tissue or gingivectomy with electrosurgery. A simplified technique using orthodontic elastomers was recently proposed and shown to be both efficient and effective.3
Placement of stainless steel crowns with window facings is the most time-consuming of the anterior esthetically desirable procedures. A two-step procedure is required to place a stainless steel crown with a window facing. The preparation is almost identical to that for a strip crown except that no facial undercut is needed. Contouring and crimping of the stainless steel crown can provide adequate retention and a good marginal fit. Esthetically, these crowns are not as pleasing as the strip crowns because there is usually some metal showing. They are indicated for severely decayed teeth or children with evident severe bruxism.
Many manufactures sell pre-veneered stainless steel crowns. A few studies have addressed their success in primary anterior teeth. More tooth structure reduction is required for veneered stainless steel crowns to accommodate their thickness. The advantages of these crowns are that they are (1) relatively less technique sensitive and (2) less time-consuming than resin composite crowns and stainless steel crowns with window facings. However, crimping of facial margins cannot be performed, and retention relies mainly on the lingual surfaces. In cases of anterior crowding, they can become very difficult to fit.
Esthetically, resin composite crowns are the best option among the other substitutes. In terms of gingival health, properly finished resin composite crowns are also better than either stainless steel crowns with window facings or veneered stainless steel crowns. However, adequate remaining tooth structure and controllable gingival hemorrhage are crucial for their success. Studies have reported high parental satisfaction with veneered stainless steel crowns.4,5 The failure of the resin facings can be problematic, and these crowns cannot be repaired easily, as opposed to resin composite crowns. The stainless steel crowns with window facings are very retentive and can be used for teeth with minimal remaining structure. The facings may be dislodged as with veneered stainless steel crowns. Owing to their time-consuming and compromised esthetics compared with other options, stainless steel crowns are not very promising for a future in which alternative and easier solutions may be available.