Differences in periodontal parameters between SPT patients who regularly and irregularly visited the dental clinic analyzed at tooth level: a 14-year retrospective cohort study.

The purpose of this study was to evaluate the periodontal status of patients who routinely did SPT, when compared to patients that did not SPT. This retrospective cohort study was conducted at a general dental office from 2001 to 2019. Patients aged 18 to 81 years who visited the dental office over a 10-year period were assigned into two groups: an SPT group, which included patients who continually visited the dental office for SPT one or more times every year, and an irregular group, consisting of patients who did not visit the dental office at least once a year.

Risk factors for tooth loss with a mean follow-up period of 13.9 years in supportive periodontal therapy patients.

Background: Clinical evidence indicates that there are various risk factors of tooth loss. However, the degree of this risk among other risk factors remains unclear. In this retrospective cohort study, the authors evaluated the hazard ratios of several risk factors for tooth loss.

Relationship between periodontal parameters and non-vital pulp in dental clinic patients: a cross-sectional study.

Background: Endodontic diseases, such as apical periodontitis, communicate with periodontitis and mutually exacerbate them. However, it remains unclear whether pulp condition is a risk factor for periodontal disease. The purpose of this retrospective study was to examine relations between pulp condition and periodontal parameters in Japanese patients who visited a general dental clinic.

Observation of the synchronization of chaos in mutually injected vertical-cavity surface-emitting semiconductor lasers.

Synchronization of chaotic oscillations was observed in mutually injected vertical-cavity surface-emitting lasers (VCSELs) in a low-frequency fluctuation regime. In the experiments, only one of the two polarization modes (x mode) showed synchronized oscillations, and the other polarization components (y mode) were synchronized as a result of the effect of anticorrelated oscillations that is a characteristic feature of VCSELs.

Observation of low-frequency fluctuations in vertical-cavity surface-emitting lasers.

Low-frequency fluctuations, which are typical irregular oscillations in edge-emitting semiconductor lasers, are experimentally observed for the y-polarization mode (y is the direction along the optical axis of a laser material) in a vertical-cavity surface-emitting laser with optical feedback.