BACKGROUND: To prevent the absorption and collapse of the labial bone plate of the anterior teeth, immediate implantation and socket shield technique have been increasingly applied to anterior dental aesthetic implant restoration.
OBJECTIVE: To provide a biomechanical basis for implant restoration of maxillary anterior teeth, finite element analysis was used to investigate the stress peak and distribution in different anatomical sites of natural teeth, conventional immediate implantation and socket shield technique.
METHODS: Three maxillary finite element models were established, including a maxillary incisor as a natural tooth, a conventional immediate implantation and a socket shield technique. A mechanical load of 100 N was applied to simulate and analyze the biomechanical behavior of the root, periodontal ligament (PDL), implant and surrounding bone interface.
RESULTS: The stress distribution of the natural tooth was relatively uniform under load. The maximum von Mises stress of the root, periodontal ligament, cortical bone and cancellous bone were 20.14 MPa, 2.473 MPa, 19.48 MPa and 5.068 MPa, respectively. When the conventional immediate implantation was loaded, the stress was mainly concentrated around the neck of implant. Maximum stress on the surface of the implant was 102 MPa, the cortical bone was 16.13 MPa, and the cancellous bone was 18.29 MPa. When the implantation with socket shield technique was loaded, the stress distribution of the implant was similar to that of immediate implantation. Maximum stress on the surface of the implant was 100.5 MPa, the cortical bone was 23.11 MPa, the cancellous bone was 21.66 MPa, the remaining tooth fragment was 29.42 MPa and the periodontal ligament of the tooth fragment was 1.131 MPa.
CONCLUSIONS: 1. Under static loading, both socket shield technology and conventional immediate implantation can support the esthetic restoration of anterior teeth biomechanically. 2.Under short-term follow-up, both immediate implant and socket shield technology achieved satisfactory clinical results, including bone healing and patient satisfaction. 3.The stress distribution is mainly located on the buccal bone surface of the implant and is associated with resorption of the buccal bone plate after implant replacement in both socket shield technology and conventional immediate implantation. 4.The presence of retained root fragment had an impact on the bone graft gap. In immediate implantation, the peak stress was located in the cortical bone near the implant position, while in socket shield technology, the peak stress was at the neck of the cortical bone corresponding to the retained root fragment.

To investigate the accuracy of immediate anterior implantation using static computer-assisted implant surgery (s-CAIS) and robotic computer-assisted implant surgery (r-CAIS).
One hundred and six implants were immediately inserted in the anterior zone of 69 patients using a freehand technique, s-CAIS or r-CAIS. Postoperative cone-beam computed tomography scans were matched with preoperative plans to evaluate the deviations between the planned and placed implant positions.
The global coronal deviations in the freehand, s-CAIS, and r-CAIS groups were 1.29 ± 0.52 mm, 1.01 ± 0.41 mm, and 0.62 ± 0.28 mm, respectively. Significant differences were observed in the r-CAIS group compared to both the s-CAIS group and the freehand group (p < 0.05). However, no significant differences were found between the s-CAIS group and the freehand group (p > 0.05). The global apical deviations in the freehand, s-CAIS and r-CAIS groups were 1.78 ± 0.59 mm, 1.24 ± 0.52 mm and 0.65 ± 0.27 mm, respectively, while the angular deviations in the freehand, s-CAIS and r-CAIS groups were 6.46 ± 2.21°, 2.94 ± 1.71° and 1.46 ± 0.57°, respectively. Significant differences were observed in both the global apical deviations and angular deviations among the three groups (p < 0.05).
The accuracy of immediate anterior implantation with r-CAIS was better than that with s-CAIS. This difference is attributed to better control of the coronal, vertical and axial errors during r-CAIS.
This study provides significant evidence to support the use of r-CAIS as a potential alternative in immediate anterior implantation.

When edentulism is accompanied by an impacted tooth, conventional treatment usually involves traumatic tooth extraction, which would inevitably destroy the surrounding alveolar bone and cause unfavorable esthetics, especially for anterior teeth. Recently, implant placement through the impacted tooth or residual root has been proposed as an alternative to invasive extraction. A particular type of integration has been observed between dentin/cementum and titanium implant, while enamel-implant contact has not been reported. In this article, an implant was placed through the impacted maxillary central incisor, thereby avoiding an invasive extraction surgery. The buccal section of the tooth, including crown enamel, was retained in situ for buccal alveolar ridge preservation. The follow-up results were satisfactory, and a stable enamel-implant contact was observed. Combining with previous similar studies, this technique opens intriguing possibilities and brings fresh insight for the concept of dentointegration. More histological and clinical studies with long-term follow-up are warranted before endorsing this technique in routine application.

This study presents the development and evaluation of a poly(3-hydroxybutyrate-co-4-hydroxybutyrate) (P34HB) ultrafine fiber slow-release system for in vivo osteogenic induction of human umbilical cord mesenchymal stem cells (HUCMSCs). Utilizing dual-nozzle and cell electrospinning techniques, the system encapsulates L-ascorbic acid-2-phosphate magnesium (ASP), β-glycerophosphate sodium and dexamethasone (DEX) within the fibers, ensuring sustained osteogenic differentiation. The scaffold\'s morphology, characterization, hydrophilicity, mechanical properties and cellular behavior were examined. Immediate subcutaneous implantation in rabbits was conducted to observe its ectopic osteogenic induction effect. Successfully fabricated P34HB ultrafine fiber slow-release system. Characterization confirmed the uniform distribution of HUCMSCs and inducing components within the scaffold, with no chemical reactions affecting the active components. In vitro tests showcased a prolonged release of DEX and ASP, while biocompatibility assays highlighted the scaffold\'s suitability for cellular growth. Alizarin Red, type I collagen, and osteopontin (OPN) staining verified the scaffold\'s potent osteogenic induction effect on HUCMSCs. Notably, immediate implantation into New Zealand White rabbits led to significant new bone formation within 8 weeks. These findings underscore the system\'s potential for immediate in vivo implantation without prior in vitro induction, marking a promising advancement in bone tissue engineering.

UNASSIGNED: To study the clinical application effect of two kinds of implants in the upper and lower molars.
UNASSIGNED: A selection of 120 patients (134 teeth) who underwent implant treatment in the upper and lower molars in the army hospital of the Chinese people\'s liberation army from January 2018 to June 2019 were divided into an immediate group (using immediate implantation) and a delayed group (using delayed implantation) using a random number table 60 cases (60 teeth) in each group; differences in implant success rate, buccal keratinized gingival width before and after treatment, alveolar bone absorption, periodontal pocket depth, and gingival aesthetic indicators were compared between the two groups.
UNASSIGNED: The gingival aesthetics effect of the immediate group was better than that of the delayed group on the whole and the difference was statistically significant (P<0.05); after 12 months of restoration, the implantation success rate of the immediate group was 96.67%. The deferred group was 93.33%, and the difference between the two groups was not statistically significant (P>0.05).
UNASSIGNED: Both delayed restoration and immediate implant restoration can achieve good results in implant restoration treatment in the maxillary and maxillary molars. However, immediate implantation has certain advantages in reducing the amount of alveolar bone absorption and maintaining the aesthetic effect of the gums.

BACKGROUND: To establish an immediate implantation rat model and to evaluate the effects of pre-existing periodontitis and two different socket rinse solutions on immediate implantation prognosis.
METHODS: Sprague-Dawley (SD) rats were randomly divided into three groups before immediate implantation, including the control group, the group with experimentally induced periodontitis (EP), in which rats have been experimentally induced periodontitis before implantation, and the group with induced periodontitis and with extraction sockets rinsed with three percent H2O2 (EP-H2O2), in which rats have been induced periodontitis before implantation, and extraction sockets were rinsed with three percent H2O2. Periodontitis was induced by ligating the thread around the molars for four weeks. Six weeks after titanium alloy implants were self-tapped and left to heal transmucosally, maxillae were dissected after the clinical examination to perform micro-CT and histological analysis.
RESULTS: An immediate implantation model was successfully built in rats. There was no significant difference in implant survival rates between the EP and control groups. However, the clinical examination results, micro-CT analysis, and histological analysis in EP and EP-H2O2 groups showed a significantly worse prognosis than in the control group. Three percent H2O2 showed a similar effect with saline.
CONCLUSIONS: This study presented a protocol for establishing a rat immediate implantation model and showed that periodontitis history might negatively affect the prognosis of immediate implantation. These findings urge caution and alternative strategies for patients with periodontal disease history, enhancing the long-term success of immediate implantation in dental practice. Additionally, the comparable outcomes between 3% H2O2 and saline suggest the use of saline as a cost-effective and safer alternative for implant site preparation in dental practice.

OBJECTIVE: Designed and applicated a modified customized CAD-CAM socket-shield preparation guide template in immediate implant and followed up for 3 years.
METHODS: Socket-shield technique could improve the esthetic effect of immediate implant restorations by preserving the labial fascicular bone-periodontal complex at the implant site. While the socket-shield technique is highly technique-sensitive. A modified customized CAD/CAM guided template was designed and fabricated by 3D printing. The movement of the carbide bur during preparing the socket-shield was limited by the socket-shield preparation template. In this case report, the socket-shield preparation template was used for preparing the socket-shield in the tooth root with irregular morphology and the case was followed up for 3 years.
CONCLUSIONS: The modified CAD/CAM socket-shield preparation template effectively improved the accuracy and efficiency of preparing the socket-shield by limiting the movement of the high-speed carbide bur in both in both lip-to-palatal and crown-to-root orientation. The socket-shield with accurate morphology could effectively maintain the gingival marginal level and contour.
CONCLUSIONS: The modified CAD/CAM socket-shield preparation template with the depth-locking ring effectively reduced the technique sensitivity and time consumption of the socket-shield technique, especially for tooth roots with irregular morphology.

OBJECTIVE: To study the effect of immediate implantation on the restoration effect and aesthetic indicators in patients with class III and IV bone loss of the anterior teeth.
METHODS: This retrospective study collected the data of 82 patients with single loss of anterior teeth who received tooth implantation. According to the treatment methods, these patients were divided into an observation group (N=43) and a control group (N=39). Patients from the observation group underwent immediate implantation treatment, while those from the control group received conventional implantation processing. Pink aesthetic index (PES) and gingival nipple index (GNI) were used to evaluate the aesthetic indicators. Implant stability quotient (ISQ) was applied to evaluate the stability. The incidences of complications after treatment and the success rate of implantation were also recorded and compared between two groups.
RESULTS: At the same day of completed implantation, the observation group had higher various PES index scores than those in the control group (all P<0.05) and no significant differences were found for GNI index between two groups. At the 6th month following the implantation, there was no statistical difference in various PES index scores, GNI index, ISQ value of bone type III and IV between the two groups. The treatment time for bone type III and IV in the observation group was obviously less than that in the control group (all P<0.05). There was no significant difference in the total incidence of complications between the two groups (9.30% vs 12.82%, χ2=0.634, P>0.05). The success rate of implantation in the observation group was remarkably higher than that in the control group (95.35% vs 84.62%, χ2=4.1129, P=0.041).
CONCLUSIONS: An immediate implantation treatment for patients with single loss of an anterior tooth with bone type III and IV could clearly shorten the treatment period and improve the PES scores at baseline and have better restoration and aesthetic effects.

The present study aimed to evaluate the clinical and radiographic outcomes of immediate implant placement (IIP) with guided bone regeneration (GBR) as compared to delayed implant placement (DIP) following alveolar ridge preservation (ARP) and to identify the potential risk factors influencing these outcomes.
A total of 56 patients (IIP = 28 vs. DIP = 28) with class I or II bony defects received 56 implants were included. GBR procedure using Bio-Oss® bone substitute mixed with advanced platelet-rich fibrin (A-PRF) and covered by Bio-Gide® membrane and additional A-PRF membrane was performed either simultaneously with the IIP or earlier at the time of ARP in DIP. Clinical and 3-D radiographic analyses of bone level, thickness, and density were performed at three-time intervals (T1, immediately; T2, 6-7 months; and T3, 1.5 to 2 years post-implantation), corresponding to the neck, coronal, middle, and apex of implants.
The survival rate was 100% in both groups. IIP showed significant favorable outcomes regarding distal marginal bone level (anterior maxilla, T1-T3) and neck and coronal horizontal facial bone thickness (HFBT) (posterior maxilla, T1; and anterior maxilla, T1-T3, respectively) compared to DIP. However, DIP showed significant facial bone density at the neck and coronal parts in the anterior maxilla (T1) and the coronal part in the posterior maxilla (T3). The facial marginal bone level change was positively correlated with HFBT change (P = 0.007), which is negatively correlated with the secondary implant stability (P = 0.019). The implant region (anterior or posterior maxilla) was the only factor affecting on Implant stability quotient value (ISQ) and change in HFBT (P ˂ 0.05).
Overall, the IIP combined with GBR in the post-extraction sites with pre-implant class I or II bony defects had some favorable outcomes compared to DIP after ARP. However, the clinical outcomes, ISQ value, and changes in bone level, thickness, and density from T1-T3 were comparable.

BACKGROUND: The breasts of Oriental women are characterized by an obvious scar constitution and a relatively small mammary gland volume. Thus, plastic surgery, which is now popular in the West, is not suitable for most patients in China, and Chinese surgeons are searching for symmetrical plastic surgery options that are suitable for patients with breast tumors, unilateral breast implants and an obvious scar constitution.
METHODS: Between January 2016 and December 2019, 15 patients underwent contralateral breast overlapped reconstruction (COBOR) at the Affiliated Hospital of Putian University. We assessed their clinicopathological data, complications, cosmetic satisfaction and quality of life.
RESULTS: The mean age was 41.6 years (range, 31-54 years), the average BMI was 24.36 kg/m2 (range, 20.3-28.4 kg/m2), the most common tumor location was the upper outer quadrant (n = 9), the mean preoperative tumor size was 21.11 mm (range, 7-42 mm), and 4 patients underwent neoadjuvant chemotherapy. The cancer grades and histological types were as follows: G3 nonspecial type (NST), 3 cases; G2 NST, 6 cases; G2 lobular carcinoma, 1 case; and ductal carcinoma in situ (DCIS), 5 cases. The nipple margin was negative in all of these cases. Among them, there was 1 case of poor wound healing caused by subcutaneous fat liquefaction around the incision. In another case, partial nipple necrosis occurred on the affected side due to an insufficient nipple blood supply after the operation and healed after debridement and dressing changes. There were no cases of tumor recurrence during the mean follow-up of 22.53 months (range, 11-47 months). The BREAST-Q scores showed that COBOR provided good patient satisfaction.
CONCLUSIONS: For Oriental patients with small breasts, COBOR, which results in fewer scars, good symmetry and good satisfaction, is an effective and safe surgical method. However, larger studies with longer follow-up periods are needed to obtain more reliable postoperative results.