OBJECTIVE: To observe the long-term health condition of the single-tooth dental implant at the first molar site, and to evaluate the related factors affecting the peri-implant health. METHODS: In this study, 82 patients who were treated in the Second Clinical Division, Peking University School and Hos-pital of Stomatology from January 2008 to December 2020 were enrolled. Peri-implant tissue conditions were assessed by clinical and radiographic examination. The peri-implant probing depth (PPD), modified sulcus bleeding index (mSBI), modified plaque index (mPLI) and papilla index (PI) were recorded for 278 implants. The X-ray analysis included the restoration emergence angle (REA), the clinical crown-implant ratio (cC/I), the horizontal tooth-implant distance (HTID), the contact point level (CPL) and the embrasure surface area (ESA), etc. Kruskal-Wallis rank sum test and generalized estimation equation were used for statistical analysis. RESULTS: The average age of the patients was (40.2±9.5) years (19 to 84 years), with 33 males and 49 females. The follow-up time was (4.9±3.3) years (1 to 10 years). According to the diagnostic criteria in 2018, the prevalence of peri-implantitis in this study was 14.03% on the implant level and 21.95% on the patient level. The peri-implant health rate was 19.06% on the implant level and 18.29% on the patient level. The prevalence of peri-implant mucositis was 66.91% on the implant level and 59.75% on the patient level. At the baseline, there were statistically significant differences between the peri-implant health group and peri-implantitis group in PPD, distal HTID and mesial/distal CPL, cC/I (P < 0.05), while there was no statistically significant difference in mSBI, mPLI, PI, mesial HTID, mesial/distal REA and mesial/distal ESA between the two groups. Among the differences between follow-up and baseline, there were statistically significant dif-ferences between the two groups in PPD, mesial/distal HTID, mesial/distal CPL and mesial/distal ESA (P < 0.05). Generalized estimation equation showed that PPD, mesial/distal HTID, mesial CPL, and mesial ESA had significant positive correlations with the risk of peri-implantitis in the difference between baseline and follow-up. CONCLUSION Based on the results of this study, the peri-implant health rate is still unsatisfied, and the PPD, HTID, CPL, ESA may be related to the long-term health of the implant.
Humans ; Male ; Female ; Middle Aged ; Adult ; Dental Implants, Single-Tooth/adverse effects* ; Aged ; Aged, 80 and over ; Periodontal Index ; Young Adult ; Peri-Implantitis/epidemiology*

OBJECTIVES: To study the clinical effect of the L-shape technique combined with concentrated growth factor on the horizontal bone defects of maxillary anterior teeth. METHODS: Twenty-five implants from 25 patients who underwent single maxillary anterior tooth implantation with simultaneous bone grafting were selected as the study subjects. Based on the bone grafting techniques, the patients were divided into a test group (L-shaped technique with guided bone regeneration combined with concentrated growth factor, 11 cases) and a control group (traditional guided bone regeneration combined with concentrated growth factor, 14 cases). The early discomfort and wound healing conditions in the two groups at two weeks after surgery were compared. The horizontal bone thickness, vertical bone thickness, and grayscale values in the augmentation area were measured immediately postsurgery and six months after surgery. Implant stability, hard tissue resorption within six months, and grayscale values were compared between the two groups. RESULTS: Differences in early discomfort, wound healing, implant stability, and grayscale values between the two groups were not statistically significant (P>0.05). Vertical bone thickness in the test group was significantly better than that in the control group at six months after surgery (P<0.05). The variation in horizontal bone thickness in the test group was significantly higher than that in the control group (P<0.05). CONCLUSIONS The application of the L-shape technique with concentrated growth factor for horizontal bone defects in the anterior maxillary area yielded satisfactory short-term results in terms of bone augmentation, early discomfort, wound healing, and implant stability at six months after surgery.
Humans ; Maxilla/diagnostic imaging* ; Intercellular Signaling Peptides and Proteins/therapeutic use* ; Wound Healing ; Bone Transplantation/methods* ; Dental Implantation, Endosseous/methods* ; Bone Regeneration ; Male ; Female ; Adult ; Dental Implants, Single-Tooth ; Middle Aged

Implant treatment in the esthetic area requires stable osseointegration and successful esthetic outcomes. Achieving this goal requires careful consideration of accurate implant axis and ideal three-dimensional position. Owing to the high esthetics and the special anatomical structure of the maxillary, a successful implant means a synthesized deli-beration of the residual bone dimensions, soft-tissue thickness, and the relationship of the residual alveolar ridge with the planned restoration. This article offers an in-depth analysis of the clinical decisions and key factors affecting the implant direction in the esthetic area.
Dental Implantation, Endosseous/methods* ; Dental Implants ; Esthetics, Dental ; Alveolar Ridge Augmentation/methods* ; Osseointegration ; Maxilla/surgery* ; Dental Implants, Single-Tooth

OBJECTIVES: This study aimed to evaluate the long-term clinical efficacy of simple taper retentive implants in the posterior dental area after immediate implantation for 5-7 years. METHODS: Selected from January 2015 to December 2017 in the Fourth Affiliated Hospital of Nanchang University dental clinic line tooth area immediately after the implant prosthesis, a total of 38 patients, 53 implants, were deep into (bone under 2 mm or higher) and the upper structure was repaired. In addition, after the completion of tracking observation of 60-90 months, the implant surrounding bone health was recorded and analyzed. RESULTS: After 5-7 years of follow-up, 1 of the 53 implants failed to fall out, and the implant retention rate was 98.1%. The amount of bone resorption in the proximal and distal margins 5-7 years after implant restoration was (0.16±0.94) mm and (-0.01±1.29) mm, respectively, and the difference in bone height between the proximal and distal margins of the implant and the immediate post-restoration period was not statistically significant (P>0.05). No statistically significant differences were found in the effects of periodontitis, implant site inflammation, and smoking on peri-implant marginal bone resorption (P>0.05). CONCLUSIONS The single taper-retained implant broadens the indications for immediate implant placement in the posterior region, and its deep sub-osseous placement (≥2 mm below the bone) avoids to a certain extent the disturbance of the implant by external stimuli and the exposure of the cervical abutment of the implant, with the good long-term stability of the marginal bone around the implant.
Humans ; Dental Implantation, Endosseous ; Dental Implants ; Immediate Dental Implant Loading ; Follow-Up Studies ; Dental Implants, Single-Tooth ; Alveolar Bone Loss/surgery* ; Treatment Outcome ; Dental Prosthesis, Implant-Supported ; Dental Restoration Failure

Humans ; Esthetics, Dental ; Dental Implantation, Endosseous ; Dental Implants, Single-Tooth

Objective: To evaluate the pink and white esthetics of conventional and socket shield technique (SST) immediate implant restoration. Methods: Thirty volunteers were recruited according to preset criteria, and were assigned to 3 groups. Natural teeth group (ten undergraduates or postgraduates from Peking University School and Hospital of Stomatology in January 2020, n=10): all volunteers' maxillary anterior teeth were natural teeth with healthy gingiva, and none of the teeth were restored by crowns or composite. Conventional group and SST group (patients had a maxillary central incisor immediate implant placed in Department of Prosthodontics, Peking University School and Hospital of Stomatology during October 2016 to January 2021, n=10 for each group): the volunteer had an unrestored natural maxillary central incisor, and the contralateral maxillary central incisor was restored by conventional or SST immediate implant placement, temporization and all ceramic final restoration, photos were taken 12 months post-surgery. Three groups of evaluators namely layperson (staff from Second Clinical Division of Peking University School and Hospital of Stomatology and 2 family members, n=10), dental students (class 2015 undergraduates from Peking University School and Hospital of Stomatology, n=10) and prosthodontists (from Department of Prosthodontics, Peking University School and Hospital of Stomatology, n=10) were invited to assess the esthetics using pink esthetic score (PES) and white esthetic score (WES). The results were statistically analyzed. Results: PES and WES of natural teeth group [9(8, 10) and 8(7, 10)] were significantly higher than conventional group [7(6,8) and 7(6,9)] (H=287.08, 132.79,P<0.01) and SST group [7(6, 9) and 8(7, 9)] (H=216.01, 101.21, P<0.01). SST group yielded higher PES than the conventional group (H=-71.06, P<0.01), yet had similar WES (H=-31.57, P>0.05). Dental students had significant lower PES and WES than prosthodontists (H=-120.90, -218.86, P<0.01) and layperson (H=-109.55, 134.97, P<0.01). Prosthodontists and layperson got similar PES (H=-11.36, P>0.05), however yielded different WES (H=-83.89, P<0.01). Conclusions: SST immediate implant placement obtained better pink esthetics than conventional protocol 12-month after implant surgery, profession may have significant impact on evaluators during pink and white esthetic evaluation.
Crowns ; Dental Implants ; Dental Implants, Single-Tooth ; Esthetics, Dental ; Humans ; Immediate Dental Implant Loading ; Maxilla/surgery* ; Treatment Outcome

OBJECTIVES: To evaluate the clinical effect of integrated angulated screw channel (ASC) abutment crown in implant-supported rehabilitation of the aesthetic area. METHODS: Sixteen patients who received single implant-supported rehabilitation using integrated ASC abutment crown in the aesthetic area were included in the study. After one-year follow-up, the cumulative survival rate, aesthetic effectiveness, bone resorption around implants, and patient satisfaction were analyzed through periapical film, clinical examination, and the visual analog scale (VAS). RESULTS: The implant cumulative survival rate of the integrated ASC abutment crown in the implant-supported rehabilitation of the aesthetic area was 100%. The average pink esthetic index scores reached 9.5, and the white esthetic index scores reached 9.4. The mean marginal bone loss of implants was (0.439±0.123) mm at the mesial side and (0.341±0.118) mm at the distal side. The average VAS satisfaction score was 8.9, which showed that all patients were satisfied with the final restorative effect. CONCLUSIONS Using integrated ASC abutment crown for implant restoration is an ideal implant restoration design in the aesthetic zone and can be applied clinically.
Bone Screws ; Crowns ; Dental Implants ; Dental Implants, Single-Tooth ; Dental Prosthesis, Implant-Supported ; Esthetics, Dental ; Humans

OBJECTIVE: To analyze the clinical curative effect after 5-year follow-up of single tooth implant-supported restorations in the posterior region. METHODS: In the study, patients with single tooth implant-supported restorations in the posterior region after loading 5-year in the Second Clinical Division of Peking University School and Hospital of Stomatology from October 2005 to May 2010 was enrolled. The implant survival rate, prosthetic conditions (including the structural integrity or loosening of the prosthesis, the retention of the materials used to fill access holes of screw-retained implant crowns, loosening or fractures of the implant abutment or screw) and marginal bone lever level around implants were determined by clinical and radiographic examination. RESULTS: The study was composed of 215 patients, the mean age was 48.6 years (range: 27 to 71), and 321 soft tissue implants were inserted. There were 9 implants loose and lost during the visit, the cumulative success rate was 97.2%. In the 312 remaining implants, 120 implants were placed in the upper jaws (38.5%) and 192 in the lower jaws (61.5%). Three different diameters as 3.3 mm (5 implants), 4.1 mm (115 implants) and 4.8 mm (192 implants) and three different lengths as 8 mm (21 implants), 10 mm (206 implants) and 12 mm (85 implants) were used, respectively. 277 (88.8%) cement-retained and 35 (11.2%) screw-retained implant-supported single crowns were made. The marginal bone loss (MBL) around dental implants after loading 5 years in the mesial and distal sides were (0.73±0.25) mm and (0.78±0.26) mm, respectively. There was no significant difference among MBL and bone quality, implant type, angle of abutment, prosthodontic type, crown-to-implant ratio, gender, and age of the patients (P > 0.05). The major mechanical complications after restoration involved loosening (8.6%) and fracture (2.9%) of the crown retainer screw, loss of resin covering the screw (11.4%), and the most frequent mechanical complications were loss of crown retention (14.1%) and fracture of porcelain (13.8%). The incidence of loss of crown retention was correlated with insufficient clinical crown height or using angle abutment (P < 0.05). CONCLUSION After loading 5 years, the bone level around the soft-tissue-implant placed in posterior region was stable. To minimize the frequency of mechanical complications after restoration, protocols must be established from diagnosis to the completion of treatment and follow up of implant-supported prostheses, especially in terms of adequate technical steps and careful radiographic evaluation of the components.
Crowns ; Dental Implants ; Dental Implants, Single-Tooth ; Dental Prosthesis Design ; Dental Prosthesis, Implant-Supported ; Dental Restoration Failure ; Follow-Up Studies ; Humans ; Middle Aged ; Survival Rate

OBJECTIVE: To explore the feasibility of immediate implantation after tooth extraction in the maxillary molar socket with poor bone quality beneath the sinus. METHODS: We collected the data from the patients undergoing extraction of maxillary molars with poor bone quality between the sockets and sinuses. Sinus lifting and immediate implant following the extraction were performed simultaneously in these cases, and the primary stability of the implants, wound healing, and changes of the sinus were observed. At 6 months after the operations, the crowns were installed on the implants. The masticatory function was observed, and the growth of the alveolar bones and their changes after the operations were examined using microcomputed tomography (MCT). RESULTS: We analyzed 32 extraction cases with immediate implantation in the maxillary molar sockets with poor bone quality beneath the sinus. The average age of the patients was 59.8 years, and the length and diameter of the implant ranged from 8.5 to 10 mm and from 4.5 to 5.5 mm, respectively. The torque force of the implants varied from the minimum (in which cases the implants remained fixed after insertion with fingers) to the maximum of 30 N·cm. The postoperative recovery was uneventful in all the cases and no failed or movable implants were found. At 6 months after the operation, none of the patients showed abnormalities in the sinus, and in all the cases the crowns were successfully installed on the implants with good recovery of the masticatory functions. Follow-up of the patients for 12 to 96 months after the operation showed successful immediate implantation in all the cases. After the operation, the changes of the mean alveolar ridge heights on the buccal, palatal, mesial, and distal sides of the patients were 0.8069±0.6253 mm (=1.2904, >0.1), 0.5272± 0.3331 mm (=1.5836, >0.05), 0.5416±0.4048 mm (=1.3379, >0.05), and 0.5172±0.3874 mm (=1.3351, >0.05), respectively; the change of the alveolar ridge width was 0.5522±0.4381 mm (=1.2604, >0.1) mm. The dimension of the alveolar bone underwent no significant changes after the operation in these patients. CONCLUSIONS Immediate implantation in the maxillary extraction socket with a poor bone quality can avoid damages to the sinus and achieve good outcomes with such advantages of less trauma, full use of the innate gingiva and alveolar ridge, and well preserved morphology of the alveolar ridge as compared with delayed implantation.
Dental Implantation ; methods ; Dental Implants, Single-Tooth ; Feasibility Studies ; Humans ; Immediate Dental Implant Loading ; methods ; Maxilla ; Middle Aged ; Molar ; surgery ; Tooth Extraction ; Tooth Socket ; Treatment Outcome ; X-Ray Microtomography

OBJECTIVE: To compare the clinical effects of a modified socket shield technique (SST) and the conventional immediate implant placement in the esthetic zone. METHODS: Twenty-four patients with one hopeless upper incisor were consecutively enrolled in this study. All patients were scheduled for immediate implant placement. Twelve patients underwent a modified SST (experimental group) whereas the others underwent conventional procedures (control group). Radiographic and clinical data were obtained preoperatively, immediately after surgery, and 12 months after surgery. The success rate of the implants, the pink esthetic score (PES) and patient satisfaction were analyzed. Statistical analysis was conducted using SPSS 21.0 software. RESULTS: One year after operation, the success rate of the implants was 100% in both groups. The PES and patient satisfaction of the experimental group were significantly higher than those of the control group (P<0.05). The buccal bone plate resorbed less in the experimental group than in the control group (P<0.05). CONCLUSIONS The modified SST is advantageous over the conventional immediate implant placement in terms of buccal bone and soft tissue maintenance.
Dental Implants, Single-Tooth ; Esthetics, Dental ; Humans ; Immediate Dental Implant Loading ; Tooth Extraction ; Tooth Socket ; Treatment Outcome