Influence of periodontal therapy on chemical and mineralogical characteristics of root surface

Introduction: Dental cementum is an avascular and non-innervated mineralized tissue covering the root surface that is continuously and slowly created throughout life. The distribution of minerals and different chemical elements in mature dental cementum shows great variability, and changes in chemical and mineralogical characteristics also occur during the implementation of different therapeutic procedures in periodontology. Aim: This research was to compare the chemical and mineralogical characteristics after performing three different therapeutic procedures. Material and Method: The examined sample included a total number of 60 teeth in which there was an indication for extraction. All extracted teeth that were part of the sample had stage III and IV of periodontal disease. The total number of teeth that met the criteria for participation in this research were divided into three groups of 20 teeth, according to which of the performed therapeutic procedures was applied: (1) Group I: Teeth that have undergone a therapeutic procedure including usage of ultrasonic instruments and manual instruments. All of them were chemically analysed using ICP with mass spectrophotometry and X-ray diffractometry; (2) Group II: Consisted of teeth in which, after ultrasonic instrumentation, laser-assisted treatment with Er: YAG laser were used that were chemically analysed using ICP with mass spectrophotometry and X-ray diffractometry and (3) Control group: Impacted teeth with an indication for extraction or teeth that are for extraction for a non-periodontal reason. These teeth were chemically analysed using ICP with mass spectrophotometry and X-ray diffractometry. Results: There was a reduction in the calcium present in the treated root surfaces, and the calcium loss was greater in the laser treated root surfaces. There were changes in the ratio of organic and inorganic constituents of cementum observed in root surfaces of treated teeth compared to root surfaces obtained from healthy teeth. The greatest loss of inorganic components in the cement structure was observed in surfaces treated with conventional periodontal therapy. There was a significantly closer ratio of the organic and inorganic part of cementum on root surfaces obtained from laser-treated teeth and healthy teeth. There were insignificant changes in the mineralogical composition of the cementum observed in treated teeth compared to root surfaces obtained from healthy teeth. Root surfaces originating from healthy teeth were dominated by hydroxyl-apatite and carbonate apatite, root surfaces treated with conventional periodontal therapy are dominated by amorphous apatite (indicating loss of the proper crystal structure of apatite), while root surfaces from teeth treated with laser-assisted therapy, apart from hydroxyl apatite, portlandite (calcium hydroxide with a grid similar to brushite) also occurs. Conclusion: Changes in the chemical characteristics of the root surfaces occur during the application of any therapeutic procedure in relation to the surfaces of healthy teeth. There are numerous chemical changes observed in untreated periodontal affected root surfaces compared to root surfaces obtained from healthy teeth.