IADR Abstract Archives
Functional Matrix: The Lamina Dura and Orthodontic Tooth Movement
Objectives: To elucidate whether the lamina dura of the alveolus of a tooth socket can be observed on a radiograph as a continuous white line before, during and after orthodontic tooth movement.
Methods: Periapical and panoramic radiographs were used. Xrays of teeth of untreated patients from private practices and clinics were studied to see the normal lamina dura. Xrays were located of teeth of patients under going orthodontic tooth movement of at least 3 mm or more. The tooth movement could be either horizontally or vertical. Some xrays of patients who were retained for atleast one year were studied to locate the lamina dura. The observations were made by Orthodontists and Periodontists. The team tried to locate a continuous line or lamina dura or partials of the lamina dura. Statistical analyses were used to assist in interpreting the data. We tried ANOVA, t-tests and graphs.
Results: (1) On x-rays of non treated persons, the lamina dura was observed as a continuous white line in the alveolus around the tooth root. (2) On the radiograph, the lamina dura was not fully visible in the alveolus of tooth roots that had been moved for 3 mm or more (these were primarily persons being treated by extracting two or four premolars to assist in orthodontic treatment). (3) The xrays of persons that were taken at least a year following the completion of active treatment (retention) appeared more normal, i.e. the lamina dura was usually in tact. (4) Intruded anterior teeth resembled diseased teeth.
Conclusions: Dentists should be aware of this transitional condition since the profession generally use the lamina dura as an aid in diagnosis and treatment planning. This author wonders whether any teeth have been treated by root canal therapy or the tooth replaced by an implant due to the absence of the lamina dura.
Methods: Periapical and panoramic radiographs were used. Xrays of teeth of untreated patients from private practices and clinics were studied to see the normal lamina dura. Xrays were located of teeth of patients under going orthodontic tooth movement of at least 3 mm or more. The tooth movement could be either horizontally or vertical. Some xrays of patients who were retained for atleast one year were studied to locate the lamina dura. The observations were made by Orthodontists and Periodontists. The team tried to locate a continuous line or lamina dura or partials of the lamina dura. Statistical analyses were used to assist in interpreting the data. We tried ANOVA, t-tests and graphs.
Results: (1) On x-rays of non treated persons, the lamina dura was observed as a continuous white line in the alveolus around the tooth root. (2) On the radiograph, the lamina dura was not fully visible in the alveolus of tooth roots that had been moved for 3 mm or more (these were primarily persons being treated by extracting two or four premolars to assist in orthodontic treatment). (3) The xrays of persons that were taken at least a year following the completion of active treatment (retention) appeared more normal, i.e. the lamina dura was usually in tact. (4) Intruded anterior teeth resembled diseased teeth.
Conclusions: Dentists should be aware of this transitional condition since the profession generally use the lamina dura as an aid in diagnosis and treatment planning. This author wonders whether any teeth have been treated by root canal therapy or the tooth replaced by an implant due to the absence of the lamina dura.