International Journal of Periodontics & Restorative Dentistry最新文献

This study clinically and histologically evaluated the outcome of a porcineapatite xenograft used to elevate the maxillary sinus floor in a severely atrophic ridge. A two-stage crestal window sinus elevation protocol was conducted in 24 patients with crestal bone ≤ 2 mm. Highly porous porcine carbonate apatite moistened with saline solution was placed in the elevated sinus cavity as the sole grafting material. Bone core biopsy samples were taken at 6, 9, and 12 months after sinus augmentation surgery (at implant placement). Treatment outcomes were assessed using microCT (μCT) and histologic analysis. Statistical analysis was performed using nonparametric Kruskal-Wallis test, followed by post-hoc Dunn multiple comparison test. At 6 months after implant placement, all implants achieved good primary stability (insertion torque ≥ 30 Ncm) and successfully osseointegrated. The residual graft amount (mean ± SE) was low (11.91% ± 1.99%) at 6 months and further decreased (6.11% ± 2.64%) by 12 months. On the contrary, the amount of new bone detected was 18.94% ± 4.08% at 6 months and was significantly (P < .05) increased (40.16% ± 5.27%) at 12 months. Histologic assessment revealed osteoclasts actively resorbing the graft as well as osteoblasts actively forming new bone. In the severely atrophic maxilla, the porcine-apatite xenograft promotes new bone formation while being slowly absorbed. Within the limited sample size, the porcine-apatite xenograft seems to be a good graft material for crestal window sinus augmentation.

The purpose of this study was to evaluate the effect of 2% chlorhexidine (CHX) on an etch-and rinse adhesive to dentin. Caries-free molars were selected and processed to expose a flat dentin surface. The specimens were bonded with a composite resin by an etch-and-rinse adhesive, which was pretreated with 2% CHX for 0, 15, 30, 45, and 60 seconds. The microtensile bond strength (MTBS) was evaluated before and after thermocycling. No significant differences were observed between groups before thermocycling. The 60-second CHX-pretreated group showed a significantly greater MTBS than the control group after thermocycling. The 2% CHX pretreatment could improve the bonding strength of the etch-and-rinse adhesive and slow down the aging progress of the bonding interface.

Successful rehabilitation of the anterior maxilla remains a challenge, primarily due to postextraction ridge collapse, which can lead to gingival recession and a nonesthetic appearance. The socket shield technique presents a viable alternative for immediate dental implant placement in the esthetic zone. This pilot study aimed to evaluate the survival, complication rates, and marginal bone loss around body-shift implants placed in fresh extraction sockets with the socket shield technique to replace maxillary incisors. After socket shield preparation, 14 hopeless incisors were extracted and immediately replaced by a body-shift implant (Inverta, Southern Implants) at baseline. Patients were followed up for 12 to 39 months (mean: 18.1 ± 8.2 months). The average age was 52.3 ± 16.9 years, and the survival rate was 100%. One socket shield presented minimal internal exposure that was successfully treated with a connective tissue graft. The mean PES score was 12.9 ± 1.2. Mean interproximal marginal bone loss was -0.4 ± 0.5 mm. Body-shift implants can be a promising alternative for immediate tooth replacement combined with the socket shield technique. The superior esthetic outcomes remained stable, suggesting that the extra space created by the narrow cervical portion of the implant is beneficial for preserving the alveolar bone and limiting internal shield exposure.

A retrospective chart review was conducted of CBCT images captured between November 2019 and April 2021 on patients who underwent dental implant placement and had a periodontal charting. The buccal and lingual bone thickness around the implants was measured as an average of three measurements taken from the buccal and lingual aspects of implants. Implants with peri-implantitis were placed in Group 1, and implants with peri-implant mucositis or good peri-implant health were placed in Group 2. Wilcoxon rank sum test was used to compare the differences between the bone thicknesses of the groups. In total, 93 CBCT radiographs were screened, and 15 CBCT images with both an implant and corresponding periodontal charting were analyzed. Of the 15 implants examined, 5 presented with peri-implantitis (33%), 1 with peri-implant mucositis, and 9 with good peri-implant health. Within the limitations of this study, buccal bone thickness averaging ≥ 1.10 mm or midlingual probing depths ≤ 3.4 mm correlates with a more favorable peri-implant response. Larger studies are needed to substantiate these findings.

Over the past two decades, the Khoury plate technique has been widely utilized with much success to facilitate bone augmentation in critically deficient bone areas. Simply, the technique includes harvesting autogenous bone plates and utilizing them with external screw fixation. The rigidity of the bone plates enclosing the bony defect on both the buccal and lingual surfaces allows for tension-free bone remodeling to occur, favoring an ideal bone-forming environment. Following, a 4- to 6-month healing period, a flap is raised, screws may be removed, and implants are placed. With advancements made in tissue engineering, a novel mineral-organic resorbable bone adhesive (MORBA) formulated from underwater biomimetic marine proteins has recently been utilized for immediate bone-to-bone or bone-to-metal fixation. MORBA is a synthetic, injectable, self-setting, and resorbable load-bearing adhesive biomaterial that exhibits over 300 pounds of fixation strength. The unique adhesive properties of MORBA enable it to immediately stabilize dental implants into host bone. The present article describes a novel modification of the Khoury plate technique that utilizes MORBA as a substitute for screws during bone plate fixation. A step-by-step protocol is described that utilizes this novel biomaterial, favoring a more biologic approach to this conventional technique. This novel modification is surgically easier to conduct and is a more biocompatible option that avoids screw fixation and removal.

Osteoporosis is an increasingly prevalent disease. The development of an osteoporosis-like experimental animal model is of great importance for the study of peri-implant osteogenesis in osteoporosis. The present authors aimed to establish a rapid modeling method of osteoporotic rabbits for implant-bone analysis and validate whether the models can affect the implant osseointegration. The present study included 29 female New Zealand rabbits (age: 5 to 6 months). Two rabbits were lost during anesthetization. Of the remaining 27 rabbits, 18 received an ovariectomy, with 9 receiving dexamethasone injections for 8 weeks (OVX+D group) and 9 receiving equivalent-volume saline injections (OVX group). As a control group, the remaining 9 rabbits were sham-operated and received an equivalent volume of normal saline (SHAM group). Then, serum biochemical markers of bone metabolism were detected and densitometric measurements were performed. Implants were then placed in the tibias of each rabbit. Bone samples (including implants) were obtained after 4, 8, and 12 weeks of healing and were subjected to histologic and histomorphometric analyses. The results showed that the OVX+D group experienced a 32% reduction in bone mineral density (BMD) from baseline. The BMD of the OVX+D group was significantly lower than that of the SHAM and OVX groups. Moreover, alkaline phosphatase (ALP) blood concentrations of in the OVX+D group were increased significantly. The osteoporotic rabbits exhibited marked decreases in osseointegration, characterized by slowed bone formation and decreased bone-to-implant contact (BIC). The combination of an ovariectomy and dexamethasone injections could experimentally induce osteoporosis in rabbits in the short term, which can be used as an appropriate animal model to study the osseointegration of implants under osteoporosis.

This retrospective clinical study compared two different professional maintenance therapy (MT) approaches (with and without periodic removal and decontamination of prosthetic components) on peri-implant inflammatory clinical and biochemical parameters after 5 years of implant function. A retrospective analysis based on patient records was used to assess inflammatory clinical and biochemical parameters around dental implants placed by the same clinician in a private practice. The Plaque Index (PI), peri-implant probing depth (PPD), mucosal recession (REC), bleeding on probing (BOP), and radiographic marginal bone level were determined at baseline and at each follow-up year. Moreover, at the last follow-up visit, the peri-implant intrasulcular levels of active metalloproteinasis 8 (aMMP-8) were also assessed. All participants were under MT with a 6-month recall interval. A total of 92 patients with 132 implants were selected. At the end of the study period, 12 patients with 12 implants were classified as dropouts. The remaining 80 patients and 120 implants were classified into two groups: Group 1 (42 patients, 62 implants) received MT with periodic removal and decontamination of prosthetic components; Group 2 (38 patients, 58 implants) received MT without periodic removal and decontamination of prosthetic components. No statistical differences were found between the groups regarding PI, PPD, and REC. Group 1 presented a statistically significant higher number of sites with BOP (12.4% vs 6.2%). Marginal bone loss was statistically higher in Group 2 than in Group 1 (0.23 ± 0.6 mm vs 0.78 ± 0.3 mm). Intrasulcular levels of aMMP-8 were statistically higher in Group 1 than in Group 2. The supplemental application of periodic removal and decontamination of prosthetic components during MT had a significantly positive effect on the inflammatory status of peri-implant tissues.

Purpose: To evaluate the clinical efficacy of the coronally advanced lingual flap (CALF) technique in terms of the extent of lingual and buccal flap advancement, the maintenance of primary wound closure, and safety in comparison to buccal flap advancement alone during horizontal ridge augmentation in the posterior mandible.

Materials and methods: A total of 14 patients were randomly allocated to two different groups: buccal flap advancement without the CALF technique (control), referred to as the NO-CALF group, and buccal flap advancement with the CALF technique (test), referred to as the CALF group. Wound healing was monitored weekly for the first 4 weeks, then at 2, 4, 6, and 9 months postoperatively for any soft tissue dehiscence (titanium mesh [TM] exposure) along the incision line. The extent of lingual and buccal flap advancement was measured, and any intraoperative and postoperative CALF-related complications were reported.

Results: The difference between groups was statistically significant (P < .0001) in terms of (1) TM exposure: 83.3% of cases in the NO-CALF group showed early Class П exposures, whereas the CALF group showed no exposure; (2) mean lingual flap advancement: 3.9 ± 1.1 mm and 14.4 ± 3.8 mm for the NO-CALF and CALF groups, respectively; and (3) mean buccal flap advancement: 15.8 ± 2.1 mm and 10.5 ± 1.4 mm for the NO-CALF and CALF groups, respectively. There were no reported complications related to the CALF technique.

Conclusion: Tension-free primary wound closure was facilitated and maintained during the healing period by applying the CALF technique, which is a reliable technique to safely advance the lingual flap coronally.

Few studies have reported the outcomes of short implants with a follow-up time > 10 years. This retrospective study aimed to evaluate the long-term outcomes of short locking-taper implants supporting single crowns in the posterior region. Patients who received these supporting implants (≤ 8 mm) in the posterior region from 2008 to 2010 were included. The clinical and radiographic outcomes and patient satisfaction were recorded. A total of 18 patients with 34 implants were included. The cumulative survival rate was 91.4% and 83.3% at implant and patient levels, respectively. Tooth brushing habit and history of periodontitis were significantly associated with implant failure (P < .05). The median marginal bone loss (MBL) was 0.24 mm (IQR: 0.01 to 0.98 mm). Biologic and technical complications occurred in 14.7% and 17.8% of implants, respectively. The mean modified Sulcus Bleeding Index was 0.52 ± 0.63, and the mean peri-implant probing depth was 2.38 ± 0.79 mm. All patients were at least quite satisfied, with the majority of patients (88.9%) being fully satisfied with the treatment. Within the limitations of this study, the short locking-taper implants supporting single crowns in the posterior region achieved promising outcomes in the long-term follow-up.

Purpose: To evaluate tooth discoloration after the use of calcium silicate-based materials and to examine the effect of internal bleaching on tooth discoloration.

Materials and methods: The specimens were randomly divided into two experimental groups (n = 45) and a control group (n = 6). Cavities were filled with ProRoot MTA (Dentsply) in Group 1 and Biodentine (Septodont) in Group 2. Color measurements were taken with a spectrophotometer before and after the application of materials at 1 week and then at 13, and 6 months. After 6 months, Groups 1 and 2 were divided into three subgroups according to internal bleaching techniques. All color change ratios and lightness differences were calculated using the CIE L*a*b* system. Data were analyzed using repeated ANOVA and the Kruskal-Wallis test (P = .05).

Results: There were statistically significant differences between Groups 1 and 2 at all time intervals (P < .05). Group 1 showed more discoloration than Group 2 (P < .05). There were no significant differences between the bleaching agents (P > .05). Additionally, specimens in both groups became lighter than their initial color (P < .05).

Conclusion: Teeth treated with ProRoot MTA exhibited darkening at 1 week that increased over time, whereas those treated with Biodentine maintained the lightness for 6 months.