Correlation Between Root Resorption and Dentin Sialoprotein Upon Application of Different Orthodontic Forces.

Correlation Between Root Resorption and Dentin Sialoprotein Upon Application of Different Orthodontic Forces.

Correlation Between Root Resorption and Dentin Sialoprotein Upon Application of Different Orthodontic Forces, a Split-mouth Technique, a Randomized Clinical Trial

Since root resorption is a frequent consequence of orthodontic treatment, DSP are non-collagenous dentin-specific matrix proteins postulated to be involved in the mineralization of pre-dentin into dentin. Calculating the amount of DSP -Dentine Sialo Protein- produced upon root resorption might be an indicative biological marker for root resorption

Histological and radiographic observations have shown that root resorption is a frequent consequence of orthodontic treatment (Reitan, 1974; Rygh, 1977; Harry and Sims, 1982). In most patients this resorption is minor and of no importance. A few teeth however exhibit severe resorption. In a study by Goldson and Henrikson (1975) it was found that 6 per cent of 924 teeth were resorped more than 2 mm after treatment with a Begg appliance and Malmgren et al. ( 1982) found a similar degree of root resorption in 10 percent of 264 incisors treated with an edgewise appliance and in 5 percent of 176 incisors treated with a Begg appliance(1). Root resorption resulting from undesirable orthodontic force is an unwanted sequele , that fears all orthodontists including their experts as well(2). DSP are non-collagenous dentin-specific matrix proteins postulated to be involved in the mineralization of pre-dentin into dentin (3,4) .Dentin undergoes continuous deposition throughout life as a secondary dentin only on the pulpal surface. Therefore, these proteins are not routinely released into the surrounding space as dentin does not undergo the process of remodeling as in bone. It is only in the presence of active external root resorption that these proteins could be freed into the periodontal ligament space(5). Since periapical -intraoral- radiograph gives a two dimensional information, which detect root resorption after 60- 70% of the mineralized tissue is lost. (6) So, it's not sensitive in detecting early root resorption so in this study the investigators introduce the biological marker DSP to monitor root resorption from its onset by collecting samples from the GCF -gingival crevicular fluid- for its detection. Calculating the amount of DSP -Dentine Sialo Protein- produced upon root resorption might be an indicative biological marker for root resorption.

27 female patients coming to the Orthodontic department, Cairo University seeking orthodontic treatment, where their age ranges from 15 - 18 years, where their treatment plan include extraction of upper first premolars, and using the split-mouth technique, one side will be control group without application of force where the other side will receive intrusive mechanics for the same patient in the upper arch (one side will not receive any force and the same tooth on the other side of the arch will suffer intrusive mechanics, that's why named SPLIT MOUTH TECHNIQUE - as if the arch is split into two subjects, one control subject (tooth) and the other study subject (tooth) . According to the amount of force of the working side, the total number of patients will be divided into 3 groups. Each of 9 subjects, the first group where a light force will be applied (10 gm), the second group where moderate force will be applied (25gm), the third group where heavy force will be applied(100 gram).

concentration of DSP is expected to be secreted into the gingival crevicular fluid upon root resorption

Inclusion Criteria: Adolescent female patients age ranging from 15- 18 yrs, with the full set of the permanent dentition. No previous orthodontic treatment. Class I crowding or Class II malocclusion whose treatment requires extraction of first maxillary premolars. Adequate oral hygiene. Exclusion Criteria: Systematic diseases. Bad Oral hygiene. Missing permanent teeth (except for third molars). Uncontrolled Pathological Conditions that may contra-indicate immediate orthodontic treatment (caries, gingivitis, periodontitis).