Impact of smoking on marginal bone loss

PURPOSE: To compare marginal implant bone loss (MBL), survival, and radiographic evidence of success of dental implants among smokers and nonsmokers. MATERIALS AND METHODS: Consecutive records of 161 patients (aged 23 to 89 years, mean 57 years) treated with a total of 646 implants between the years 1995 and 1998 were examined. Patients were divided into 3 groups: nonsmokers, moderate smokers, and heavy smokers. Tobacco exposure was calculated by cigarettes per day and by pack-years. Follow-up ranged from 1 to 7 years (mean 3.8 years). Postoperative panoramic radiographs obtained before implant exposure and annually thereafter were analyzed for MBL changes. The influence of smoking and other variables on MBL was analyzed at all implant sites. RESULTS: Generally, smokers had more MBL than nonsmokers (0.153 +/- 0.092 mm and 0.047 +/- 0.048 mm, respectively; P < .001). When each jaw was examined separately, smoking had a greater effect on MBL in the maxilla than in the mandible (0.158 +/- 0.171 mm versus 0.146 +/- 0.158 mm, respectively; P < .001). Furthermore, in the maxilla, heavy smokers had the greatest amount of MBL (0.1897 +/- 0.1825 mm), followed by moderate smokers (0.123 +/- 0.156 mm) and nonsmokers (0.0460 +/- 0.070 mm) (P < .001). In the mandible, there was no distinction between heavy and moderate smokers, and both had greater MBL than nonsmokers (P < .001). Only 3 of the 646 implants failed; the cumulative survival rate was 99.5%. Overall radiographic success rate was 93.2%. Nonsmokers had a higher radiographic success rate (97.1%) than smokers (87.8%) (P < .001). CONCLUSIONS: This study demonstrated a relationship between MBL and smoking habits. A higher incidence of MBL was found in the smoking group, and this was more pronounced in the maxilla.     

初始黏膜厚度对种植体边缘骨吸收影响的研究进展

［摘要］ 稳定的颈部边缘骨水平是种植体长期成功的一个重要指标,而黏膜厚度作为一个影响种植体边缘骨吸收(marginal bone loss, MBL)的因素一直被研究和讨论。大多数的临床研究和动物实验表明,相对于薄黏膜(≤2 mm),厚黏膜（＞2 mm）区域的种植体颈部MBL更少。基于推测黏膜厚度影响重建种植体生物学宽度(biologic width,BW)从而影响种植体MBL,学者们根据缺牙区初始的黏膜厚度,尝试调整临床种植操作。有学者增加黏膜厚度达到了减少种植体MBL的目的,也有学者根据黏膜厚度调节种植深度达到了避免种植体表面早期暴露的目的。本文就初始黏膜厚度对种植体颈部MBL影响和对临床种植参考意义的相关研究进展综述如下。     

Clinical and radiographic comparison of implants in regenerated or native bone: 5-year results

Purpose: The aim of this study was to test whether or not implants associated with bone regeneration show the same survival and success rates as implants placed in native bone in patients requiring both forms of therapy. Material and methods: Thirty‐four patients (median age of 60.3 years, range 18–77.7 years) had been treated 5 years before the follow‐up examination. Machined screw‐type implants were inserted following one of two surgical procedures: (1) simultaneously with a guided bone regeneration (GBR) procedure, which involved grafting with xenogenic bone substitute material, autogenous bone or a mixture of the two and defect covering with a bio‐absorbable collagen membrane (test) and (2) standard implantation procedure without bone regeneration (control). For data recording, one test and one control implant from each patient were assessed. Examination included measurements of plaque control record (PCR), probing pocket depth (PPD), bleeding on probing (BOP), width of keratinized mucosa (KM), frequency of situations with supra‐mucosal location of the crown margin, implant survival assessment and radiographic examination. Radiographs were digitized to assess the marginal bone level (MBL). Differences between groups were tested using the one‐sample t‐test. The estimation of survival rate was based on Kaplan–Meier analysis. Results: The follow‐up period of the 34 GBR and 34 control implants ranged from 49 to 70 months (median time 57 months). Cumulative survival rates reached 100% for the GBR group and 94.1% for the control group without statistical significance. No statistically significant differences for clinical and radiographic parameters were found between the two groups regarding PCR, BOP, PPD, KM and MBL. Conclusion: The present study showed that, clinically, implants placed with concomitant bone regeneration did not performed differently from implants placed into native bone with respect to implant survival, marginal bone height and peri‐implant soft tissue parameters.     

Marginal bone loss pattern around hydroxyapatite-coated versus commercially pure titanium implants after up to 12 years of follow-up

PURPOSE: The purpose of this study was to compare the marginal bone loss (MBL), complications, and 12-year survival rates of commercially pure titanium (cpTi) and hydroxyapatite (HA)-coated implants placed in the maxilla. MATERIALS AND METHODS: The study group consisted of 120 patients (77 women, 43 men) treated from 1988 to 1997. A total of 388 implants (156 cpTi and 232 HA-coated) were placed in the maxilla. There were 126 immediate (32.5%) and 262 (67.5%) nonimmediate implants. Patients were evaluated annually. Mean follow-up was 60 +/- 32.3 months. MBL was measured on radiographs using the implant threads as the dimensional reference. MBL, complications, and 12-year survival and success rates were correlated with implant coating, time of implantation, implant dimensions, and position in arch. RESULTS: Total mean MBL was 1.07 +/- 2.16 mm. MBL was significantly lower with cpTi implants (0.55 +/- 1.04 mm) compared to HA-coated implants (1.51 +/- 2.71 mm) (P < .001). No statistical difference in regard to MBL was found between immediate and nonimmediate implants (0.86 +/- 1.8 mm vs 1.16 +/- 2.3 mm). The total 12-year survival rate was 91.4%. HA-coated implants had a significantly higher 12-year survival rate than cpTi implants (93.2% vs 89%; P < .03). Nonimmediate implants had a significantly higher failure rate (8.2%) than the immediate implants (1.3%) (P < .009). No correlation was found between type of implant coating and late implant failure. DISCUSSION: Immediate implants can serve as a predictable option, providing higher survival and success rates. HA-coated implants tended to fail less during the surgical phase, but had higher mean MBL compared to cpTi implants. CONCLUSIONS: HA-coated implants had greater MBL than cpTi implants but a higher 12-year survival rate. Immediate implants had a lower failure rate than the nonimmediate implants in this study population.     

Prospective clinical evaluation of 835 multithreaded tapered screw-vent implants: results after two years of functional loading

Multithreaded tapered screw implants have been used for several years, but lack of clinical documentation about marginal bone stability and survival rates have raised concerns about the design among some clinicians. This study prospectively evaluated the survival rates, success rates, and marginal bone stability of multithreaded tapered screw implants. A total of 835 implants in diameters of 3.7 mm (9%), 4.7 mm (76%), and 6.0 mm (15%) were placed in 328 patients using a single-stage, delayed-loading protocol. The implants were restored with a variety of prostheses and monitored over 2 years of functional loading. Five implants failed and were removed before loading. Cumulative implant survival was 99.4% (n = 835); differences between mandibular (99.0%, n = 408) and maxillary (99.8%, n = 427) implants were not statistically significant (P > .20). Mean marginal bone resorption was 1.66 mm (+/- 0.13 mm). Six implants failed to meet the success criteria by sustaining mesial and distal bone loss below the first implant thread; however, they remained stable and continued functioning without pain or inflammation. Cumulative implant success was 98.6% (n = 835); differences between maxillary (98.6%) and mandibular (98.8%) implants were not statistically significant (P > .20). Success rates by implant diameter were 98.6% (3.7 mm), 98.4% (4.7 mm), and 100% (6 mm). After 2 years of functional loading, survival and success rates for multithreaded tapered implants placed in a nonsubmerged protocol equaled or surpassed those of single-thread, straight-walled implant historical controls.     

A radiographic evaluation of cervical bone loss associated with immediate and delayed implants placed for fixed restorations in edentulous jaws

BACKGROUND: Placement of dental implants is considered a successful and predictable procedure. An important biological benefit is the preservation of bone height following implantation. The purpose of this study was to examine the cervical bone loss (CBL) and its correlation with implant characteristics and anatomic factors, 1 to 8 years post-implantation of immediate and delayed implants. METHODS: A total of 381 implants (144 immediate and 237 delayed) were placed in 44 edentulous patients (53 jaws) for fixed ceramometal restoration from 1989 to 1996. The mean mesial and distal cervical bone resorption of each implant was measured using panoramic radiographs, by an objective examiner using a computerized scanner before second stage surgery and 1 to 8 years (mean 3.5 years) follow-up. The length of the implant served as an internal standard. The examiner had no prior information on the examined implants. RESULTS: Total CBL was 0.78 +/- 1.22 mm. There was a significant difference (P = 0.049) between CBL of immediate implants compared to delayed ones. Implants > 13 mm showed a significantly (P < 0.001) lower CBL than shorter implants. Hydroxyapatite-coated implants had a higher CBL (P < 0.001) compared to commercially pure titanium implants (P < 0.001). The CBL of maxillary implants was higher than mandibular implants (P < 0.001). Step-wise multiple regression pr.obability tests demonstrated that implant location followed by coating, length, and timing of placement were the most important parameters for implant success (R2 = 0.102). CONCLUSION: Cervical bone loss around dental implants is influenced by location, coating, length, and implant timing.     

Multiple teeth replacement with endosseous one-piece yttrium-stabilized zirconia dental implants

Objectives: The purpose of this study is to clinically and radiographically evaluate survival and success rate of multiple zirconia dental implants positioned in each patient during a follow-up period of at least 12 months up to 48 months. Study Design: Eight patients were treated for multiple edentulism with 29 zirconia dental implants. All implants received immediate temporary restorations and 6 months after surgery were definitively restored. 6 months to 4 years after implant insertion, a clinical-radiographic evaluation was performed in order to estimate peri-implant tissues health and peri-implant marginal bone loss. Results: Survival rate within follow-up period was therefore 100%. The average marginal bone loss (MBL) from baseline to 6 months was +1.375±0.388 mm; from 6 months to 1 year was +0.22±0.598 mm; from 1 year to 2 years was -0.368±0.387 mm; from 2 years to 3 years was -0.0669±0.425 mm; from 3 years to 4 years +0.048±0.262 mm. The mean marginal bone loss at 4 years from the implants insertion was +1.208 mm. Conclusions: According to several studies, when using a radiographic criterion for implant success, marginal bone loss below 0.9-1.6 mm during the first year in function can be considered acceptable. In our work, radiographic measurements of MBL showed values not exceeding 1.6 mm during the first year of loading and also 1 year up to 4 years after surgery further marginal bone loss was minimal and not significant. This peri-implant bone preservation may be associated to the absence of micro-gap between fixture and abutment since zirconia dental implants are one-piece implant. Moreover, zirconia is characterized by high biocompatibility and it accumulates significantly fewer bacteria than titanium. Key words:Zirconia dental implants, multiple implants, radiographic evaluation, marginal bone loss (MBL).     

同期植骨的即刻与延期种植在上颌中切牙区的骨量对比研究

目的:分析比较上颌中切牙即刻种植与延期种植同期唇侧植骨术的疗效。方法:选择2018年度行上颌中切牙区单颗牙种植的患者57例,根据治疗方式分为即刻组(28例)和延期组(29例),2组均同期行唇侧引导骨再生技术(guided bone regeneration,GBR)。所有患者于术前(T0)、术后即刻(T1)、术后6个月(T2)进行锥形束CT(CBCT)检查,并通过影像分析软件测量种植体肩台下2 mm和10 mm处的唇侧水平骨量。结果:在观察期内,2组种植体存留率均为100%。在T1~T2时间段内,即刻组患者2个位点处的唇侧骨板吸收量小于延期组(P<0.05),即刻组2个位点处唇侧剩余骨厚度>2 mm的患者多于延期组,且即刻组获得更好的美学效果与更高的满意度评分。结论:与延期种植相比,即刻种植同期唇侧植骨更有利于减缓牙槽骨吸收,能维持种植体周围软硬组织稳定。     

Evaluation of 316 narrow diameter implants followed for 5–10 years: a clinical and radiographic retrospective study

Objectives: Narrow diameter implants (NDIs; diameter >3.75 mm) are useful in replacement of missing incisor teeth and when the bucco‐lingual width of the edentulous crest is insufficient. The present study evaluated the success and survival rates, peri‐implant parameters, mechanical and prosthetic post‐loading complications of NDIs followed over a 10‐year period. Material and methods: Three hundred and sixteen NDIs were inserted into 139 patients and restored with 120 prostheses. Clinical and radiographic assessment data were collected during recall visits. Implant success (SC), cumulative survival rate (CSR), marginal bone loss (MBL), peri‐implant conditions and prosthetic complications were assessed. Cox proportional hazards regression analysis, Kaplan–Meier survival curves with the log‐rank test and life table analysis were used to evaluate the outcome of NDIs within comparable subgroups. MBL and peri‐implant parameters measured annually were further analyzed. Results: The mean follow‐up time was 9.1 years (range: 60–124 months). Twelve implants were lost in the healing phase and two during function. The mean MBL in the maxilla and the mandible was 1.32 ± 0.13 and 1.28 ± 0.3 mm, respectively, after 10 years. SC and CSR were 91.4% and 92.3%, respectively, after 124 months. Smoking and posterior localization were associated with an increased risk of failure. Cement loosening (16.8%) was the most common prosthetic complication. No implants were fractured. Conclusions: NDIs can be used with confidence where a regular diameter implant is not suitable. MBL around NDIs occurred predominantly within 2 years of loading and was minimal thereafter. Further studies are required to clarify the possible risks associated with smoking and posterior placement. To cite this article:
Arιsan V, Bolukbasι N, Ersanlι S, Ozdemir T. Evaluation of 316 narrow diameter implants followed for 5–10 years: a clinical and radiographic retrospective study.
Clin. Oral Impl. Res. 21 , 2010; 296–307.
doi: 10.1111/j.1600‐0501.2009.01840.x     

Maxillary alveolar ridge reconstruction with nonvascularized autogenous block bone: clinical results.

PURPOSE: The purposes of this study were to evaluate the clinical success of bone reconstruction of the severely atrophic maxilla using autogenous bone harvested from the anterosuperior edge of iliac wing and to analyze the clinical success and the marginal bone level of dental implants placed 4 to 5 months after bone grafting and before prosthetic rehabilitation. PATIENTS AND METHODS: Fifty-six patients (18 men, 38 women) aged 27 to 63 years were included in the study and required treatment for maxillary atrophy. All patients selected were scheduled for onlay bone graft and titanium implants in a 2-stage procedure. The dental implants were inserted 4 to 5 months after grafting. RESULTS: No major complications were observed from the donor sites. A total of 129 onlay bone grafts were used to augment 56 severely resorbed maxillas. Three out of 129 bone grafts had to be removed because of early exposure occurring with bone grafts placed to increase the vertical dimension of the alveolar ridge. One hundred sixty-two implants were placed in the area of bone augmentation. Seven implants failed to integrate and were successfully re-placed without any need for additional bone grafting. The clinical measurements for bone resorption around implants revealed a mean bone loss of 0.05 mm (+/- 0.2); the marginal bone level evaluated with periapical radiographies was 0.3 mm (+/- 0.4) at implant placement and 0.1 mm (+/- 0.3) 6 months after placement. CONCLUSION: The success rate of the block grafts was very good. The clinical and radiographic bone observations showed a very low rate of resorption after bone graft and implant placement. Therefore, on the basis of this preliminary study, iliac bone grafts (from the anterosuperior edge of the iliac wing) can be considered a promising treatment for severe maxillary atrophy.     

Implant Abutment Cleaning by Plasma of Argon: 5‐Year Follow‐Up of a Randomized Controlled Trial

Background: Contamination of implant abutments could potentially influence the peri‐implant tissue inflammatory response. The aim of the present study is to assess the radiographic bone changes around customized, platform‐switched abutments placed according to the “one‐abutment‐one‐time” protocol, with and without plasma of argon cleaning treatment. Methods: Thirty healthy patients with thin gingival biotype (<1 mm) and history of periodontal disease received one maxillary implant each. Immediately before abutment connection, patients were randomly assigned to control group (cleaning protocol by steaming) or test group (plasma of argon treatment). Outcome measures were: 1) success rate of implants and prostheses; 2) biologic and prosthetic complications; 3) peri‐implant marginal bone loss (MBL); 4) esthetic and periodontal parameters; and 5) patient satisfaction. Results: Neither implants nor prostheses were lost in either group at the 5‐year follow‐up examination. Overall, both groups showed a slight amount of peri‐implant bone loss from baseline to 5 years. A statistically higher mean MBL was found in the control group compared with the test group at 6, 24, and 60 months after crown connection. Nevertheless, during the entire follow‐up period, intragroup comparison demonstrated statistically significant mean MBL in the control group, but not in the test group. The test group showed a higher mean gain at the soft tissue margin, but not for the papilla. All implants showed good periodontal parameters, with no significant differences between groups. Conclusion: Plasma of argon could be used to disinfect implant abutments before insertion to minimize future peri‐implant bone resorption.     

Apical and marginal bone alterations around implants in maxillary sinus augmentation grafted with autogenous bone or bovine bone material and simultaneous or delayed dental implant positioning

Objective: A re‐pneumatization phenomenon was recorded in sinuses grafted with different materials. The specific aims of this paper were to assess the dental implant survival rate and the behavior of marginal and apical bone remodeling around dental implants placed following sinus augmentation. Materials and methods: A retrospective study was conducted on consecutive patients treated in two surgical centers. Different surgical techniques were adopted for sinus augmentation: simultaneous or delayed dental implant insertion with bovine bone‐material augmentation or autologous bone grafting (chin and iliac crest). Survival rates were recorded for the overall number of implants (patients of group A). Apical and marginal bone levels (ABL and MBL, respectively) were radiographically measured, and statistical analysis was performed in implants of a subgroup of patients (group B). Results: A total of 282 dental implants were positioned. Recorded cumulative survival rates (CSRs) were 95.6% and 100% for autogenous and bovine bone material, respectively, while CSRs at 2‐year follow‐up for immediate and delayed procedures were 99.3% and 96.5%. For the subgroup B, 57 sinus augmentation procedures were performed in 39 patients, with the positioning of 154 implants. Generally, the apical‐ and marginal‐bone resorption of the bovine bone‐material group was less than that of the autogenous group. The differences between the ABL values of the bovine bone‐material and iliac‐crest groups were statistically significant at 1 year, whereas this significance disappeared at the 2‐year follow‐up; tests showed that a statistical difference was recorded in the bovine bone‐material group between the 1‐ and 2‐year follow‐ups. With regard to MBL comparisons between simultaneous and delayed implantation, the differences maintained their significance at the 2‐year follow‐up also. Conclusions: Differences regarding apical bone alteration between autogenous bone from the iliac crest and bovine bone material at the 1‐ and 2‐year follow‐ups, as well as in the bovine bone‐material group between the 1‐ and 2‐year follow‐ups, attested to slower but more prolonged physiologic bone remodeling in the bovine‐graft‐material group than in the autogenous‐bone group. The MBL analysis showed that remodeling in the delayed implant group demonstrated a greater resorption in the cervical portion than was seen in the simultaneous implant group. To cite this article:
Sbordone L, Levin L, Guidetti F, Sbordone C, Glikman A, Schwartz‐Arad D. Apical and marginal bone alterations around implants in maxillary sinus augmentation grafted with autogenous bone or bovine bone material and simultaneous or delayed dental implant positioning.
Clin. Oral Impl. Res 22 , 2011; 485–491
doi: 10.1111/j.1600‐0501.2010.02030.x     

Marginal Bone Loss in Implants Placed in the Maxillary Sinus Grafted With Anorganic Bovine Bone: A Prospective Clinical and Radiographic Study

Background: Sinus elevation is a reliable and often‐used technique. Success of implants placed in such situations, even with bone substitutes alone, prompted the authors of this study to strive for bone loss close to zero and research variables that cause higher or lower rates of resorption. The objective of this study is to evaluate survival rates and marginal bone loss (MBL) around implants placed in sites treated with maxillary sinus augmentation using anorganic bovine bone (ABB), and identify surgical and prosthetic prognostic variables. Methods: Fifty‐five implants were placed in 30 grafted maxillary sinuses in 24 patients. Periapical radiographs were evaluated immediately after implant placement (baseline), 6 months, and at the most recent follow‐up. MBL was calculated from the difference between initial and final measurements, taking into account a distortion rate for each radiograph compared with original implant measurements. Results: Survival rate was 98.2%, with only one implant lost (100% survival rate after loading) over a mean follow‐up time of 2.0 ± 0.9 years. MBL ranged from 0 to 2.85 mm: 75.9% of mesial sites and 83.4% of distal sites showed <1 mm of MBL, whereas 35.2% of mesial sites and 37% of distal sites exhibited no bone loss. MBL was significantly (P <0.05) greater in open‐flap compared with flapless surgery. Conclusions: Within the limitations of the present study, it was concluded that maxillary sinus elevation with 100% ABB gives predictable results, and that flapless surgery results in less MBL compared with traditional open‐flap surgery.     

Therapy of peri-implantitis with resective surgery. A 3-year clinical trial on rough screw-shaped oral implants. Part II: radiographic outcome

OBJECTIVES: This clinical study on therapy of peri-implantitis aimed to compare the marginal bone loss of implants treated with different surgical approaches: implantoplasty and peri-implant resective surgery only. MATERIAL AND METHODS: Over a period of 6 years, 10 patients (20 implants) were treated with implantoplasty (test group) and 9 had resective surgery (control group). A computerized analysis of radiographs was performed to calculate marginal bone loss (MBL) values mesial and distal to the implants. The measurement system was set by means of known implant sizes. Data on MBL were collected at the time of peri-implantitis diagnosis, 1, 2 and 3 years after surgery. RESULTS: There was no difference between the mean MBL values three years after implantoplasty in the test group: 0 and 0.01 mm of MBL mesial and distal to the implant were found (P>0.05). Conversely, the mean MBL values recorded in the control group were statistically different: 1.44 and 1.54 mm of MBL mesial and distal to the implant were found (P<0.05) 3 years after resective surgery. Moreover, the variation of peri-implant marginal bone after peri-implantitis surgical treatment was significantly lower in the test group than in the control group (P<0.05). CONCLUSIONS: The results of this radiographic research suggested that implantoplasty was an effective treatment of peri-implant infections and peri-implantitis progression.     

Clinical outcome of narrow diameter implants: a retrospective study of 510 implants

BACKGROUND: Narrow diameter implants ([NDIs]; diameter <3.75 mm) are a potential solution for specific clinical situations such as reduced interradicular bone, thin alveolar crest, and replacement of teeth with small cervical diameter. NDIs have been available in clinical practice since the 1990s, but only a few studies have analyzed their clinical outcome. METHODS: From November 1996 to February 2004, 237 patients were selected, and 510 NDIs were inserted. Implant diameter ranged from 3.0 to 3.5 mm, multiple implant systems were used, and 255 implants were restored immediately without loading (IRWL). No statistical differences were detected among the studied variables. Consequently, marginal bone loss (MBL) was considered an indicator of the success rate (SCR) to evaluate the effect of several host-, surgery-, and implant-related factors. A general linear model (GLM) was used to detect those variables statistically associated with MBL. RESULTS: Only three of 510 implants were lost (survival rate [SRR] = 99.4%), and no differences were detected among the studied variables. On the contrary, the GLM showed that delayed loading and longer (>13 mm) and larger (3.4 and 3.5 mm) NDIs reduced MBL. CONCLUSIONS: NDIs have a high SRR and SCR, similar to those reported in previous studies of regular diameter implants. Moreover, IRWL of NDIs is a reliable procedure, although a slightly higher bone resorption is reported compared to delayed loading. No implant fractures were detected in the present series.     

Success of dental implants placed in intraoral block bone grafts

BACKGROUND: The purpose of this study was to evaluate the survival and success of dental implants placed in alveolar bone following augmentation using intraoral block bone grafts. METHODS: A consecutive retrospective study was conducted on patients who had onlay bone grafts for vertical or horizontal augmentations followed by dental implantation from 1999 to 2001. Files of 50 healthy patients who received 129 implants in augmented sites were reviewed. Implant survival, radiologic implant success (marginal bone loss), and complications were recorded. RESULTS: Follow-up from time of implantation ranged from 6 to 67 months (mean: 24.3 +/- 11.2 months). Ranges of implant widths and lengths were 3.25 to 4.7 mm and 10 to 16 mm, respectively. The overall survival rate was 96.9% (four implants were removed). Marginal bone loss around implants ranged from 0 to 3.3 mm (average: 0.22 +/- 0.45 mm). Only 5% of the implants presented marginal bone loss > or =1.5 mm over the follow-up time. CONCLUSIONS: Intraoral bone block graft surgery is a predictable operation for the use of dental implants. Implant placement in augmented areas presents high survival and radiologic success rates with minimal bone loss.     

Clinical and radiographic characteristics of single‐tooth replacements preceded by local ridge augmentation: a prospective randomized clinical trial

Objectives: To assess in a randomized‐clinical trial the influence of three augmentation techniques (chinbone with or without a Bio‐Gide^® membrane and Bio‐Oss^® with a Bio‐Gide^® membrane) on the clinical and radiographic characteristics of hard and soft tissues around implants and adjacent teeth in the reconstructed maxillary anterior region, up to 1 year after functional loading. Materials and methods: Ninety‐three patients requesting single‐tooth replacement and presenting with a horizontal (bucco‐palatinal) bone deficiency were included. After augmentation, 93 ITI‐Esthetic^Plus implants were placed. Clinical variables, standardized photographs and radiographs were analysed to assess the impact on the levels of the marginal gingiva (MGL) and marginal bone (MBL) around implants and adjacent teeth, viz at pre‐augmentation, pre‐implantation (TPI) and 1 (T₁) and 12 (T₁₂) months after final crown placement. Results: Implant survival was 97.8%. No significant differences were observed in the treatment outcomes of the three augmentation modalities. Combining the three modalities, a slight but significant increase in the implants approximal pocket depth was found between T₁ and T₁₂. Approximal bone loss at the implant between T₁ and T₁₂ was 0.14 ± 0.76 mm (mesial) and 0.14 ± 0.47 mm (distal); the approximal MGL slightly increased (mesial: 0.24 ± 0.46 mm, distal: 0.25 ± 0.66 mm), and the buccal MGL decreased (0.11 ± 0.61 mm). Bone loss at the adjacent teeth, although minor, was significant between TPI and T₁. No correlations were observed in changes of MBL and MGL. Conclusions: None of the three applied augmentation technique procedures influenced the characteristics of the MGL and MBL or the implant survival of single‐tooth replacements. Peri‐implant hard and soft tissues were very stable in the first year after loading.     

T2DM患者即刻种植预后及影响因素的回顾性研究

目的:比较T2DM患者与全身健康患者应用即刻种植的效果,探究可能影响因素.方法:收集156例患者,植入185枚种植体的病例资料.T2DM组21例,种植体24枚,正常血糖对照组135例,种植体161枚.对比两组间的边缘骨吸收、种植体成功率、并发症发病率,对数据进行比较,并探讨不同修复因素的影响.结果:两组间MBL值无显著...     

Maxillary osteotomy with an interpositional bone graft and implants for reconstruction of the severely resorbed maxilla: a clinical report

PURPOSE: The aim of this study was to report the outcome of using a maxillary osteotomy with an interpositional bone graft and implants in the treatment of extremely resorbed maxillae. MATERIALS AND METHODS: Twenty-two consecutive patients (mean age 65.7 years) were included in the study. Bone grafts from the iliac bone were used. The patients were followed in a standardized clinical and radiographic method for up to 5 years. RESULTS: A total of 176 Astra Tioblast ST implants were placed. Six implant losses occurred. All patients had fixed prostheses. Only minor bone resorption (1.0 to 1.5 mm) occurred in the bone graft, as well as a certain amount of marginal bone remodeling around the implants (1.0 to 1.9 mm) during periods up to 5 years. Remodeling and resorption in the bone graft and around the implants occurred during the first postoperative year. The results represent cumulative success and survival rates of 97%, which is comparative to implant integration in conventional maxillary bone. DISCUSSION AND CONCLUSIONS: The orthognathic surgical technique using maxillary osteotomy with interpositional bone graft and implants in a 2-stage procedure has been shown to be a predictable and reliable method for rehabilitation of patients with extreme resorption of the maxilla when conventional implant surgical methods cannot be used. Although the procedures are trying for the patients, overall satisfaction with the end result can be rewarding.     

Influence of Crown/Implant Ratio on Marginal Bone Loss: A Systematic Review

Background: With the increased use of short dental implants (<10 mm), a high crown/implant (C/I) ratio has become a common finding. However, the effect of the C/I ratio on the marginal bone loss (MBL) has not yet been examined extensively. Hence, the aim of the present systematic review is to explore the influence of the C/I ratio on the success rate and MBL of dental implants. Methods: Three electronic databases (PubMed, Ovid MEDLINE, and Cochrane Central) and a manual search for human trials with a minimal follow‐up of 6 months are used for the present study. A statistical analysis of the influence of the C/I ratio was performed on the peri‐implant MBL while considering follow‐up period, type of implants, implant connection, and technical and biologic complications. Results: One hundred ninety‐six potential articles were identified on the selected databases. Only 57 articles were selected for full‐text evaluation. According to the inclusion criteria, a total of 13 articles were included in this systematic review. A significant negative association between the C/I ratio and the MBL was found (P = 0.012). However, no statistically significant difference was found (P >0.15) for potential effects regarding the observation period, the type of implant connection, or between both methods of evaluating the C/I ratio. Conclusions: Within the limitations of the present study, the C/I ratio of implant‐supported restorations has an effect on peri‐implant marginal bone level. Within the range of 0.6/1 to 2.36/1, the higher the C/I ratio, the less the peri‐implant MBL.