Seung-Yun Shin

Shin SY. J Periodontal Implant Sci. 2026 ;56:e5. https://doi.org/10.5051/jpis.265601edi01

Background: Oral health is closely linked to overall health conditions, particularly in older adults. Objectives: To explore the longitudinal effects of the number of remaining natural teeth on the incidence of falls and fractures among Korean community‐dwelling adults utilising the data from the Korean Frailty and Aging Cohort Study. Methods: Participants were categorised into five categories based on their number of teeth: 0–4, 5–10, 11–20, 21–25 and more than 25. The number of remaining natural teeth was recorded using dental panoramic radiographs. Diagnostic criteria proposed by the Asian Working Group on Sarcopenia were adopted to diagnose sarcopenia. The Activities‐Specific Balance Confidence (ABC) was utilised to evaluate balance confidence. Incidences of falls and fractures were assessed at the baseline, 2‐year and 4‐year follow‐ups. Results: Among the 1404 participants initially enrolled, 1275 remained at the 2‐year follow‐up and 1030 continued through the 4‐year follow‐up. Participants with fewer teeth at baseline had significantly higher rates of falls in the preceding year. Significant differences were observed in handgrip strength, walking speed, the 5‐time chair stand test, Short Physical Performance Battery score, appendicular skeletal muscle mass index and ABC scales. In the Cox regression model, fewer than five teeth were significantly associated with increased risk of falls (HR, 1.606; 95% CI, 1.008–2.557; p = 0.046) and fractures (HR, 4.322; 95% CI, 1.037–18.015; p = 0.044) within the 4‐year follow‐up, after adjustments for potential confounders. Conclusions: Having fewer than five dentitions in older adults is a significant predictor of falls and fall‐related fractures over 4 years.

Aim: To compare the dimensional stability of a self‐retaining synthetic block bone (srBB) and synthetic bone particles (SBP) for alveolar ridge augmentation (ARA) in damaged extraction sockets. Materials and Methods: ARA was randomly performed in two centres on 57 participants presenting damaged extraction socket in a non‐molar tooth: (i) srBB and collagen membrane (srBB group, n = 29) or (ii) SBP and collagen membrane (SBP group, n = 28). Cone beam computed tomography (CBCT) was performed immediately after ARP (baseline, T0) and at 6 months (T1). T0 and T1 CBCTs were superimposed, and horizontal widths (H0–H5), vertical heights and volume changes were assessed using t ‐test. Results: Due to wound dehiscence, srBB was removed in 10 patients. The change in horizontal width at the most coronal level (H0) was significantly lower for srBB compared to SBP (srBB: 0.8 ± 1.0 mm; SBP: 1.9 ± 2.2 mm, p < 0.05). Significantly less volume decrease was seen at the bucco‐coronal level for srBB (srBB: 3.2 ± 0.6 mm ³ ; SBP: 10.4 ± 2.3 mm ³ , p < 0.05). Conclusion: Compared to synthetic bone particles, synthetic bone blocks have the potential to more effectively augment and maintain the coronal horizontal dimension and width of damaged extraction sockets for up to 6 months. However, this advantage is offset by their relatively high rates of early wound dehiscence. Trial Registration: Korean Clinical Research information service ( CRIS ) ( KCT0005462 )

Na-Yeon Tak, Su-Jin Kim, Jae-In Ryu, Belong Cho, Nam-Yoon Kim, Seung-Min Yang, Kyoung-Man Min, In-Woo Cho, Ji-Young Han, Seung-Yun Shin. J Korean Acad Oral Health 2024;48:186-91. https://doi.org/10.11149/jkaoh.2024.48.4.186

Aim: To determine bone regeneration following sinus floor elevation (SFE) at sites with or without prior sinus membrane perforation.Materials and Methods: The sinus membranes in the maxillary sinuses of 12 rabbits were intentionally perforated (≥ 5 mm) on one side, followed by application of a collagen matrix. SFE was performed on both sinuses after 8 weeks of healing, presenting two groups: SFE with a previous large sinus membrane perforation (group SFE_Perf), and in an intact sinus (group SFE). The animals were euthanized at 2 and 4 weeks after SFE. Micro‐computed tomographic and histomorphometric analyses were performed.Results: The amount of newly formed bone within the augmented area did not differ significantly between the two groups at 2 weeks and 4 weeks (4.7 ± 1.0 mm² vs. 5.3 ± 1.4 mm² and 9.2 ± 1.7 mm² vs. 10.8 ± 2.2 mm², respectively, mean ± SD; p > 0.05). However, the amount of newly formed bone near the middle of the sinus membranes was significantly greater in group SFE than in group SFE_Perf (p < 0.05). There was no significant difference in the augmented volume. Fewer subepithelial glands and denser collagen fibres within the sinus membranes were observed in group SFE_Perf than in group SFE.Conclusions: A large perforation of the sinus membrane followed by an 8‐week healing period did not jeopardize new bone formation following SFE.

Objectives: This study evaluated the impact of masticatory difficulty on the development and progression of malnutrition, frailty, sarcopenia, and disability in community‐dwelling adults, using data from the Korean Frailty and Aging Cohort Study.Methods: Participants were categorised by presence of masticatory difficulty. The Fried frailty phenotype, mini‐nutritional assessments, and diagnostic criteria proposed by Asian Working Group on Sarcopenia were adopted to diagnose frailty, malnutrition, and sarcopenia respectively. Physical disabilities were measured using the Korean activities of daily living (ADL) and Korean instrumental activities of daily living (IADL) scales.Results: A total of, 3010 participants were initially enrolled, 2864 participants remained in the study after 2 years, reflecting a 95.1% retention compliance. At baseline, the prevalence of frailty (28.0% vs. 18.1%), malnutrition (1.5% vs. 0.8%), IADL disability (10.1% vs. 7.7%), and ADL disability (10.8% vs. 8.0%) was higher among those experiencing masticatory difficulty than in those without. After 2 years, baseline masticatory difficulty was associated with the incidence of malnutrition (OR, 2.62; 95% CI, 0.99–6.90; p = 0.042) after full adjustment for confounders. However, no associations were found between baseline masticatory difficulty and the incidence of frailty, sarcopenia or physical disability over 2 years after adjustment. Additionally, masticatory difficulty did not affect the persistence or remission of malnutrition, frailty, sarcopenia, IADL disability, and ADL disability in individuals who already had these conditions at baseline.Conclusion: Restoring chewing function and masticatory satisfaction improves not only oral health but also contributes to overall health and promotes healthy aging in older individuals.

Aim: To determine the effects of implant timing and type of soft‐tissue grafting on histological and histomorphometric outcomes in a preclinical model.Materials and Methods: Four implant placement protocols were randomly applied at the mesial root sites of the third and fourth mandibular premolars in 10 mongrel dogs: immediate placement (group IP), early placement (group EP), delayed placement with/without alveolar ridge preservation (groups ARP and DP, respectively). A connective‐tissue graft (CTG) or porcine‐derived volume‐stable collagen matrix (VCMX) was applied to enhance the ridge profile (simultaneously with implant placement in group IP and staged for others), resulting in five sites for each combination. All dogs were sacrificed 3 months after soft‐tissue grafting. Histological and histomorphometric analyses were performed, and the data were analysed descriptively.Results: CTG and VCMX were difficult to differentiate from the augmented area. The median total tissue thickness on the buccal aspect of the implant was largest in group IP/CTG (between 2.78 and 3.87 mm). The soft‐tissue thickness was generally favourable with CTG at all implant placement timings. Within the DP groups, CTG yielded statistically significantly larger total and soft‐tissue thickness than VCMX (p < .05). Among the groups with VCMX, group EP/VCMX showed the largest soft‐tissue thickness at apical levels to the implant shoulder.Conclusions: CTG generally led to greater tissue thickness than VCMX.

Park JB, et al. J Periodontal Implant Sci. 2024 Dec;54:e33. https://doi.org/10.5051/jpis.245406edi01

Park JB, et al. J Periodontal Implant Sci. 2024 Jun;54(3):137-138. https://doi.org/10.5051/jpis.245403edi01

Park JB, et al. J Periodontal Implant Sci. 2024 Apr;54(2):63-64. https://doi.org/10.5051/jpis.245402edi01