Caries and periodontal reactions associated with long-term use of different types of bonded lingual retainers

An investigation was carried out (1) to test the tendency of different types of bonded retainers to accumulate plaque and calculus and (2) to find out whether long-term use of bonded retainers caused any damage to the teeth involved. Two test groups of patients--one with 3-3 retainers made of 0.032-inch spiral wire, and the other with 3-3 retainers made of 0.032-inch plain wire--and a reference group of persons without 3-3 retainers were compared. Also, a test group of patients with retainers made of flexible spiral wire (0.0195 inch) bonded lingually to each anterior tooth in the maxilla was compared to a reference group of patients with retention plates in the maxilla. All the persons selected had received routine orthodontic treatment with a multibonded edgewise light wire technique and had been out of active treatment for 1 to 8 years. Different indices were used to score accumulation of plaque and calculus, prevalence of caries, and periodontal reactions. The findings indicated that there was no basis on which to claim that retainers made of spiral wire accumulated more plaque and calculus than retainers made of plain wire. The presence of a bonded lingual retainer and the occasional accumulation of plaque and calculus gingival to the retainer wire after long-term use caused no apparent damage to the hard and soft tissues adjacent to the wire.