Department of Periodontics, VA Hospital, Greater Los Angeles Healthcare System, California, USA; Catholic University Sacro Cuore, Rome, Italy.
University of Southern California School of Dentistry, Los Angeles, CA, USA.
Arch Oral Biol. 2020 Apr;112:104678. doi: 10.1016/j.archoralbio.2020.104678. Epub 2020 Feb 6.
To evaluate posterior implant placement feasibility shortly after tooth extraction in non-grafted sockets with and without dehiscence at the time of extraction.
Ninety-five patients requiring posterior extractions entered this cross-sectional study. They were divided in three groups after extraction: G1 without dehiscence, G2 with dehiscence ≤5 and G3 > 5 mm. CBCT were taken prior to implant placement at an average of 12-weeks post-extraction to evaluate the need for grafting, cortical bone formation and bucco-lingual width (BLW). Actual BLW (n = 60) were compared to minimum expected BLW in 3 scenarios of BLW thickness averaging 6.4-7.4-8.4 mm. Peri-implant tissues were assessed for pocket formation and inflammation following established success criteria.
New cortical bone formation and sufficient BLW made implant placement feasible in sites with and without dehiscence at the time of extraction after an average healing time of 11.9 ± 2.4weeks (range: 8-18). Total average CBCT BLW was 10.1 ± 1.6 mm. All groups had a significantly higher BLW, than scenarios 1-3 (p < 0.0001). Molars were 20 times more likely than premolars to heal with BLW>10 mm (OR = 20; RR = 4.2; CI95 %: 5.3-74.2; p < 0.0001). Dehiscence sockets were 1.5 times more likely than non-dehiscenced sockets to present BLW ≤ 10 mm (OR = 1.5; RR = 0.6; CI95 %:0.9-2.5; p = 0.08). A band of keratinized tissue was present in all implants and success rates were 100 % at an average follow-up of 51.0 ± 23.4 months.
Implant placement is feasible without socket grafting shortly after tooth extraction. Non-grafted sockets present a significant osteogenic potential. Dehiscence sockets are likely to self-repair by forming a new cortical plate. The unassisted regenerated intra-socket bone allows for functional implant stability long-term.
评估拔牙后即刻无骨开窗和有骨开窗（骨开窗宽度≤5mm 和>5mm）的非移植牙槽窝中即刻植入后牙的可行性。
本横断面研究纳入 95 例需行后牙拔除的患者。拔牙后将患者分为 3 组：G1 组无骨开窗，G2 组骨开窗宽度≤5mm，G3 组骨开窗宽度>5mm。拔牙后平均 12 周时，在植入前进行 CBCT 检查，以评估是否需要植骨、皮质骨形成和颊舌向宽度（BLW）。实际 BLW（n=60）与 3 种 BLW 厚度平均为 6.4-7.4-8.4mm 时的最小预期 BLW 进行比较。根据既定的成功标准，评估种植体周围组织的袋状形成和炎症情况。
在平均 11.9±2.4 周（8-18 周）的愈合时间后，新皮质骨形成和足够的 BLW 使拔牙后即刻有骨开窗和无骨开窗的部位能够进行种植体植入。总平均 CBCT BLW 为 10.1±1.6mm。所有组的 BLW 均显著高于方案 1-3（p<0.0001）。磨牙发生 BLW>10mm 的可能性是前磨牙的 20 倍（OR=20；RR=4.2；95%CI：5.3-74.2；p<0.0001）。骨开窗牙槽窝发生 BLW≤10mm 的可能性是无骨开窗牙槽窝的 1.5 倍（OR=1.5；RR=0.6；95%CI：0.9-2.5；p=0.08）。所有种植体均有角化组织带，在平均 51.0±23.4 个月的随访中，成功率为 100%。
拔牙后即刻不进行牙槽窝植骨即可进行种植体植入。非移植牙槽窝具有显著的成骨潜能。骨开窗牙槽窝可能通过形成新的皮质板而自行修复。未辅助再生的牙槽内骨可长期提供功能性种植体稳定性。
