Complications Encountered in Temporary Orthodontic Anchorage Device Therapy

Chitosan gel prevents the growth of Porphyromonas gingivalis, Tannerella forsythia, and Treponema denticola in mini-implant during orthodontic treatment

Aims

We evaluated the effect of chitosan gel on total oral bacteria, Porphyromonas gingivalis, Tannerella forsythia, and Treponema denticola, during orthodontic treatment with mini-implants.

Material and methods

Thirty subjects with 52 orthodontic mini-implants were divided into three groups: one group was treated with chitosan gel, the other group with chlorhexidine gel, and the control group with placebo. The plaque of the orthodontic peri-mini-implant area was collected before and after gel treatment. The total oral bacteria and red-complex bacteria of P. pingivalis, T. forsythia, and T. denticola were determined with reverse transcription-quantitative PCR.

Results

Thirty-four orthodontic mini-implants (65.38%) appeared as healthy and showed no clinical signs of inflammation. The total number of bacteria was reduced after chitosan gel application. The highest decrease in the proportion of P. gingivalis was observed in the chlorhexidine gel application group, which showed a value of 70.86%, whereas the chitosan gel application showed a reduction of only 26.59%, and the control gel application showed the lowest reduction effect of only 2.55%. The difference in the reduction between gel application groups was significant (P < 0.05) for T. denticola and T. forsythia.

Conclusion

The gel containing chitosan reduced the levels of total oral bacteria and red-complex bacteria.

Dental, skeletal and soft tissue effects of the Distal Jet appliance: A prospective clinical study

Objective:

This study evaluated the dental, skeletal and soft tissue effects in Class II malocclusion patients treated with Distal Jet appliance, compared to an untreated control group.

Methods:

44 patients with Class II malocclusion were divided into two groups: Group 1 (experimental) - 22 patients, mean age of 12.7 years, treated with the Distal Jet appliance for a mean period of 1.2 years; Group 2 (control) - 22 untreated patients, mean age of 12.2 years, followed by a mean period of 1.2 years. Lateral cephalograms were obtained before treatment (T₀) and at the end of the distalization (T₁).Independent t test was used to identify intergroup differences.

Results:

When compared to control group, the Distal Jet produced a significant increase in mandibular plane angle (0.7 ± 2.0^o). The maxillary second molars presented distal inclination (6.6 ± 3.8^o), distalization (1.1 ± 1.1 mm) and extrusion (1.3 ± 2.1 mm). The maxillary first molars distalized by 1.2 ± 1.4 mm. The maxillary first premolars mesialized by 3.4 ± 1.1 mm. The maxillary incisors showed slight labial tipping of 4.3 ± 4.7^o and were protruded by 2.4 ± 1.7 mm. There were no significant changes in the facial profile. The overjet increased 1.5 ± 1.1 mm and overbite had no significant changes.

Conclusion:

The Distal Jet appliance is effective to distalize the maxillary first molars, but promotes increase in mandibular plane angle, distal inclination, extrusion and distalization of maxillary second molars, mesialization of maxillary first premolars, proclination and protrusion of maxillary incisors, and increase in overjet, when compared to a control group.