A clinical comparison of sealant and amalgam in the treatment of pits and fissures. 1. Clinical performance after 18 months.

A comparative study was made of two alternative methods for the clinical trea tmen t of occlusal pits and fissures in the early post-eruption state. Contralateral pairs of permanent first and second molars wore carefully selected so that one mo/ar couM be given a preventive treatment with pit and fissure soal~n t, while the paired molar surfaces were restored with amalgam. Dental Health Center criteria for color change, margin discoloration, margin adaptation, anatomic form and the presence of caries wore modifi’ed to increase sensitivity to the early signs of trea tmen t failure. Both treatments were evaluated independently by two examiners a t periods of zero, six, 12, and 18 men ths after placement, and at the earliest sign of sealant deterioration, the involved areas were rotrea ted and a rssume of the maintenance required to gain clinical efficacy in caries control is cited. Statistical analysis was used to compare the breakdown within each treatment group at vmious time intervals and between treatment groups. The retreatment rate for sealant was highest after 6 men ths (17.3 percen t) and declined to 7.8 percent after 18 months. There was evidence era generalized margin deterioration in more than 50 percent of amalgam restorations whereas 55 percent of the sealant margins remained not detectable clinically. PEDIATRIC DENTISTRY Vol. 2, No. 3 167 Introduction The treatment of occlusal pits and fissures with a resin sealant coating to prevent dental caries has been proven effective in a number of clinical investigations. 18 In most clinical studies, a half-mo~th design is utilized to compare a treated tooth or surface with its contralateral untreated tooth or surface as an internal reference for caries activity in the study population. One application of sealant is usually made at baseline and the efficacy of a single treatment for caries reduction is monitored at specified time intervals. Retention rates were found to vary in different studies and with various sealant materials. The clinical loss of material due to bond failure of the resin to enamel was a common problem in most studies. Typical results show a loss of sealant on permanent molars after one year of 28.6 percent in Kalispel, MT, 9 20.1 percent in Chelsea, MI,~0 32.9 percent in Alachua, FL,1~ and 29.4 percent in Birmingham, England.12 The loss of sealant continued to increase with time for each study, thus indicating the need for continual observation and periodic maintenance once sealant treatment is instituted. The clinical criteria and the protocol utilized during evaluation also vary somewhat among studies and, therefore, data are very difficult to compare. More recent studies have utilized clinical criteria developed by Cvar and Ryge~3 in coordination with those used previously for the evaluation of anterior or posterior restorations. ~4-~ Although validity has been established as a clinical testing instrument, further attempts have been made to modify the criteria to improve sensitivity. ~7,~8 It is the objective of this clinical investigation to compare, over a five-year period, two dissimilar methods for the management of defects on the pit and fissure surfaces of molar teeth. This study will address several major questions of primary importance to the dental practitioner. (1) Can a properly maintained sealant program result in 100 percent efficacy in the prevention of pit and fissure caries? (2) What are the maintenance factors and retreatment needs associated with a successful fissure sealant program? (3) HOw these factors relate to the clinical performance of similar amalgam restorations? A summary is presented of the clinical evaluations performed during the first 18 months. dren selected for treatment. Each patient had at least one pair of contralateral permanent first or second molars with the diagnosis of caries on one pit or fissure surface, the contralateral surface being caries free. Of the 110 paired occlusal surfaces treated in the study, 55 received a standard one surface amalgam a restoration while the matched surfaces were treated with a low viscosity filled resin pit and fissure sealant, b At the treatment appointment, the tooth to be sealed was polished with a non-fluoride abrasive slurry c on a rubber cup rotating at conventional speed. Isolation for the sealant treatment was obtained utilizing cotton rolls, absorbent wafers and high volume evacuation. The exposed fissure surface was conditioned for 60 seconds using the manufacturer’s etchant solution and recommended procedures, rinsed for 15 seconds and then dried thoroughly with warm air. Isolation was renewed and the freshly mixed sealant was applied immediately by drawing small increments across the fissures with a ball-tipped applicator, d pushing air ahead of the sealant flow. Isolation was maintained for three minutes from the start of mixing. The air-inhibited layer of resin was removed from the surface with a dampened cotton roll and the coating evaluated carefully for surface defects. In placing the amalgam restoration, topical anesthetic e was applied over the injection site for 30 seconds prior to the administration of local anesthetic, f and a two minute waiting period was used. Rubber dam isolation was applied and a Class I cavity was prepared and restored according to the principles taught within the Department of Pedodontics. After seven days, the patient returned to the clinic for polishing of the amalgam restoration utilizing only steel finishing burs. All operating procedures were performed by two experienced faculty members with the aid of trained auxiliary personnel. Stopwatches were used to record the exact time utilized to perform every aspect of both treatments and these data will be presented in a subsequent report. At the second appointment, baseline clinical evaluations, including color photographs and stone models for reference, were made for both treatMethods and Materials A group of children undergoing dental treatment in the Pedodontic Clinic at the University of Michigan School of Dentistry were screened by clinical and radiographic examination, and a population of 26 chilaTytin, S.S. White Division of Pennwalt Corp., King of Prussia, PA. bKerr Sealant, Kerr Manufacturing Company, Romulus, MI. (No longer commercially available.) Cxxx Silex, J. Bird Moyer Company, MOYCO, Philadelphia, PA. dKerr Cavitec Applicator, Kerr Manufacturing Company, Romudlus, MI. eHurricane, Beutlich, Inc. Chicago, Ill. fXylocaine, 2%, Astra Pharmaceutical Co., Worcester, Mass. CLINICAL EVALUATION OF SEALANT AND AMALGAM 1 b8 Dennison, St~affon, Corpron, Charbeneau ments. Similar evaluations were made at each sixmonth recall period, and both preventive and restorative treatment were rendered according to the patients needs. For clinical evaluation, the criteria developed at the Dental Health Center ~3 in San Francisco were modified as presented in Tables 1 through 5. The criteria for color change {Table 1) in the sealant were identical to those previously established. For margin discoloration (Table 2), the "Bravo" category for noticeable discoloration is divided into two ratings, dependent upon whether the length of discoloration was less than 50 percent of the exposed margin ("Bravo-l") greater than 50 percent ("Bravo-2"). The category for penetrating discoloration is similarly divided into a "Charlie-l" rating for less than 50 percent involvement and a "Charlie-2" rating for greater than 50 perceat. The criteria for margia adaptation (Table 3) were modified to detect a one-way catch of the explorer, resulting in "Alfa-l", "Alfa-2", or "Alfa-3" ratings according to the length of detectable margin. Crevice formation was also rated as "Bravo-l" or "Bravo-2" according to the extent of crevicing. The criteria for anatomic form (Table 4) were reworded distinguish the peripheral loss of material ("Bravo-l" or "Bravo-2") from a severe loss of material exposing fissure ("Charlie-l") or total loss of material ("CharTable 1. Criteria for quality evaluation Color Change* Health Center Criteria Amalgam Restoration Hotel Visually Undetectable Oscar Visually Detectable No mismatch in color Alfa Mismatch in Color Within acceptable range Bravo Mismatch in Color Outside acceptable range Charlie * Examined wet at 18 inches lie-2"). A "Charlie" rating was added to the criteria for caries (Table 5) to include retreatment necessitated by unrelated caries. In modifying the criteria, an attempt was made to increase the discrimination of Table 2. Criteria for quality evaluation Margin Discoloration (Dry) Health Modified Center Rating Criteria