• Title/Summary/Keyword: Periodontology

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Degradation rate of several types of Calcium Polyphosphate;Long term results (다양한 형태의 다공질 Calcium Polyphosphate의 생분해성에 관한 장기적인 연구)

  • Yang, S.M.;Seol, Y.J.;Kye, S.B.;Lee, I.K.;Lee, C.W.;Kim, S.Y.;Lee, Yong-Mu;Ku, Y.;Han, S.B.;Chung, C.P.;Choi, S.M.;Rhyu, I.C.
    • Journal of Periodontal and Implant Science
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    • v.33 no.2
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    • pp.301-310
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    • 2003

  • The purpose of this study is to evaluate the biocompatibility and the biorsorbability of several types of calcium polyphosphate made through change of manufacturing process for 12 month. To solve limitation of calcium phosphate, we developed a new ceramic, Calcium Polyphosphate(CPP), and report the biologic response to CPP in extraction sites of beagle dog. Porous CPP blocks were prepared by condensation of anhydrous $Ca(H_2PO_4)_2$ to form non-crystalline $Ca(PO_3)_2$ and then milled to produce CPP powder. CPP powder, CPP block, and CPP granules added with $Na_2O$ were implanted in extraction sockets and histologic observation were performed at 12 months later. Like 3 months results, histologic observation at 12 months revealed that CPP matrix were mingled with and directly apposed to new bone without any adverse tissue reaction, CPP powder show direct bony contact, but new bone formation and fibrous tissue encapsulation showed in CPP block. 10% $Na_2O$ CPP granules show more inflammatory cells infiltration around graft materials compared at 3 month, but 15% $Na_2O$ CPP granules show less. This result revealed that regardless of addition of $Na_2O$, CPP had a high affinity for bone and had been resorbed slowly. From this results, it was suggested that CPP is promising ceramic as a bone substitute and addition of $Na_2O$ help biodegradation but optimal concentration of $Na_2O$ and other additive component to increase degradation rate should be determined in further study.

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Impact of COVID-19 spread on visit intervals and clinical parameters for patients with periodontitis in supportive periodontal therapy: a retrospective study

  • Mizuho Yamazaki-Takai;Yumi Saito;Shoichi Ito;Moe Ogihara-Takeda;Tsuyoshi Katsumata;Ryo Kobayashi;Shuta Nakagawa;Tomoko Nishino;Namiko Fukuoka;Kota Hosono;Mai Yamasaki;Yosuke Yamazaki;Yuto Tsuruya;Arisa Yamaguchi;Yorimasa Ogata
    • Journal of Periodontal and Implant Science
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    • v.54 no.2
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    • pp.75-84
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    • 2024

  • Purpose: This study investigated the relationship between the number of days that hospital visits were postponed and changes in clinical parameters due to the spread of coronavirus disease 2019 (COVID-19), after the Japanese government declared a state of emergency in April 2020. Methods: Regarding the status of postponement of appointments, we analyzed the patients who had visited the Nihon University Hospital at Matsudo for more than 1 year for supportive periodontal therapy (SPT) and classified them into low-, moderate- and high-risk subgroups according to the periodontal risk assessment (PRA). Clinical parameters for periodontal disease such as probing depth (PD), full-mouth bleeding score (FMBS), full-mouth plaque score, periodontal inflamed surface area (PISA), and periodontal epithelial surface area (PESA) were analyzed in 2 periods, from October 2019 to March 2020 and after April 2020. Correlation coefficients between days of deferral and the degree of changes in clinical parameters were calculated. Results: The mean age of the 749 patients was 67.56±10.85 years, and 63.82% were female. Out of 749 patients, 33.24% deferred their SPT appointments after April 2020. The average total of postponement days was 109.49±88.84. The number of postponement days was positively correlated with changes in average PD (rs=0.474) and PESA (rs=0.443) in the high-risk subgroup of FMBS, and average PD (rs=0.293) and PESA (rs=0.253) in the highrisk subgroup of tooth number (TN). Patients belonging to the high-risk subgroups for both FMBS and TN had a positive correlation between postponement days and PISA (rs=0.56). Conclusions: The findings, the spread of COVID-19 appears to have extended the visit interval for some SPT patients. Moreover, longer visit intervals were correlated with the worsening of some clinical parameters for SPT patients with high PRA.

  • https://doi.org/10.5051/jpis.2300620031 인용 PDF