A 4-Year Prospective Study to Assess Peri-Implant Hard and Soft Tissues Adjacent to Titanium Versus Gold-Alloy Abutments in Cemented Single Implant Crowns

PURPOSE: The purpose of this prospective clinical study was to compare titanium and gold-alloy abutments when used with cemented, implant-supported single-tooth crowns. For 4 years following prosthodontic rehabilitation, these abutments were evaluated with respect to peri-implant marginal bone levels and peri-implant soft tissue parameters. MATERIALS AND METHODS: During the years 1998 to 2000, 20 patients were selected from a patient population receiving treatment in the Implantology Department at the University of Padova, Italy. They all presented with single-tooth bilateral edentulous sites in the premolar/molar region with adequate bone width, similar bone height on each side, and an occlusal scheme that allowed for the establishment of identical occlusal cusp/fossa contacts on each side. Each subject received two identical implants (one in each edentulous site). One was randomly selected to be restored with a titanium abutment and a cemented implant-supported single-tooth crown, and the other was restored with a gold-alloy abutment and a cemented implant-supported single tooth crown. Data on peri-implant marginal bone levels and soft tissue parameters were collected for 4 years after abutment and crown insertion placement and analyzed to determine whether there was a significant (p< .001) difference with respect to the type of abutments (titanium vs. gold alloy) used. RESULTS: All subjects completed the study. All 40 implants survived, resulting in a cumulative implant success rate of 100%. Statistical analysis revealed no significant differences between the two groups with respect to peri-implant marginal bone levels and soft tissue parameters. CONCLUSIONS: Within the limitations of this study, the results indicate that there was no evidence of different response with the peri-implant marginal bone and soft tissue when titanium or gold-alloy abutments were used in conjunction with the cemented, single-tooth implant restorations provided for this limited patient population. There was no evidence of different behavior of peri-implant marginal bone and of peri-implant soft tissue when titanium abutments or gold-alloy abutments were used for cemented single-tooth implant restorations in this limited patient population.     

Cemented versus screw-retained implant-supported single-tooth crowns: a 4-year prospective clinical study

PURPOSE: The purpose of this controlled prospective clinical study was to compare cemented and screw-retained implant-supported single-tooth crowns followed for 4 years following prosthetic rehabilitation with respect to peri-implant marginal bone levels, peri-implant soft tissue parameters, and prosthetic complications. MATERIALS AND METHODS: Twelve consecutive patients were selected from a patient population attending the Implantology Department at the University of Padova. They all presented with single-tooth bilateral edentulous sites in the canine/premolar/molar region with adequate bone width, similar bone height at the implant sites, and an occlusal scheme that allowed for the establishment of identical occlusal cusp/fossa contacts. Each patient received 2 identical implants (1 in each edentulous site). One was randomly selected to be restored with a cemented implant-supported single-tooth crown, and the other was restored with a screw-retained implant-supported single-tooth crown. Data on peri-implant marginal bone levels and on soft tissue parameters were collected 4 years after implant placement and analyzed to determine whether there was a significant difference with respect to the method of retention (cemented versus screw-retained). RESULTS: All patients completed the study. All 24 implants survived, resulting in a cumulative implant success rate of 100%. Statistical analysis revealed no significant differences between the 2 groups with respect to peri-implant marginal bone levels and soft tissue parameters. DISCUSSION: The data obtained with this study suggested that the choice of cementation versus screw retention for single-tooth implant restorations is likely not based on clinical results but seems to be based primarily on the clinician's preference. CONCLUSIONS: Within the limitations of this study, the results indicate that there was no evidence of different behavior of the peri-implant marginal bone and of the peri-implant soft tissue when cemented or screw-retained single-tooth implant restorations were provided for this patient population.     

Implant-supported titanium prostheses following augmentation procedures: a clinical report

BACKGROUND: This report describes a novel technique for fabricating retrievable implant-supported titanium (Ti) prostheses in patients requiring a comprehensive treatment plan involving the combined efforts of maxillofacial surgery and implant prosthodontics. METHODS: Following bone graft reconstructive surgery and implant placement prosthetic treatment was initiated by inserting ITI-Octa abutments. An impression was made, and a framework was fabricated by fusing Ti-cast frameworks to prefabricated titanium copings by laser-welding. This was followed by veneering or fabrication of a removable denture with Ti metal re-enforcement. RESULTS: Favourable clinical results have been achieved using these screw-retained Ti implant-supported restorations for patients treated with reconstructive bone graft-surgery, with clinical observation periods ranging from three to four years. CONCLUSIONS: The present observations suggest that these screw-retained implant-supported Ti prostheses may be a meaningful contribution to implant prosthodontics, facilitating retrievable restorations of optimum biocompatibility, good marginal precision and with a good esthetic result. However, controlled clinical studies are needed to establish the long-term serviceability of these Ti restorations.     

不同冠根比种植单冠修复体短期临床疗效评价

目的 评价不同冠根比的种植单冠修复体短期临床效果。方法 选择2006年1月至2010年12月在中国医科大学附属口腔医院种植中心接受种植单冠修复的152例患者,共172枚螺纹状种植体。计算种植体冠根比（crown-root ratio,CRR）,将所有种植牙按照CRR≤1和1＜CRR＜2分为两组。统计两组种植牙5年累计存留率,并测量两组种植牙在修复后3个月、1年、2年种植体周围骨吸收的数值。结果 共有5例患者5枚种植体脱落,CRR≤1组和1＜CRR＜2组种植牙5年累计存留率分别为96.52%和93.27%,差异无统计学意义（P＞0.05）;两组种植牙在修复后3个月、1年、2年种植体周围骨吸收量差异均无统计学意义（均P＞0.05）。结论 不同冠根比的种植单冠修复体5年累计存留率、周围骨吸收量均无明显差异,冠根比CRR≤1和1＜CRR＜2种植单冠修复体的短期临床效果均较好。     

Human mineralized bone in extraction sites before implant placement: preliminary results

BACKGROUND: Bone loss after tooth extraction may prevent dental implant placement. Human mineralized bone grafts can be used to restore bone volume and allow for tooth replacement with dental implants. METHODS: The authors grafted 22 sites in 18 patients with human mineralized bone after tooth extraction. They allowed molar sites 16 weeks for graft healing, placed the implants and restored them with a final crown after a four-month integration period. Single-rooted maxillary sites received implants and immediate placement of provisional crowns or underwent a delayed two-stage restoration approach. The authors used radiographs and clinical examinations to evaluate the results. RESULTS: All of the sites were restored successfully with a single-tooth implant restoration. Periapical radiographs indicated that the crestal bone levels were limited to the first thread of the implants or slightly coronal to the first thread of the implant. Clinical evaluation indicated excellent gingival health around the provisional and final restorations, without obvious gingival migration. CONCLUSIONS: The use of human mineralized bone may have significant potential to reconstruct missing bone resulting from tooth extraction and to preserve bone after tooth extraction. In addition, healed bone graft sites seem to be able to support immediate placement of a provisional crown and implant restorations. CLINICAL IMPLICATIONS: Patients who are having teeth extracted may become candidates for implant restorations when the sites are appropriately grafted to preserve and reconstruct bone volume, thus allowing for more options for reconstructing the missing tooth site.     

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目的 评价不同冠根比的种植单冠修复体短期临床效果。方法 选择2006年1月至2010年12月在中国医科大学附属口腔医院种植中心接受种植单冠修复的152例患者,共172枚螺纹状种植体。计算种植体冠根比（crown-root ratio,CRR）,将所有种植牙按照CRR≤1和1＜CRR＜2分为两组。统计两组种植牙5年累计存留率,并测量两组种植牙在修复后3个月、1年、2年种植体周围骨吸收的数值。结果 共有5例患者5枚种植体脱落,CRR≤1组和1＜CRR＜2组种植牙5年累计存留率分别为96.52%和93.27%,差异无统计学意义（P＞0.05）;两组种植牙在修复后3个月、1年、2年种植体周围骨吸收量差异均无统计学意义（均P＞0.05）。结论 不同冠根比的种植单冠修复体5年累计存留率、周围骨吸收量均无明显差异,冠根比CRR≤1和1＜CRR＜2种植单冠修复体的短期临床效果均较好。     

牙列及牙槽骨缺损固定式种植义齿修复

目的：本文报告用Replace种植体支持和固位的固定式种植义齿修复伴有颌骨缺损的牙列缺损患者12例（43个种植体）,从种植体周围组织状况,种植体及义齿稳定性,美观和功能等角度评价种植义齿的临床应用效果。方法：根据临床检查和X线片测量结果,确定治疗方案,选择Replace种植体数量、类别与规格。在颌骨成形、种植体植入、义齿修复后,定期复查。12例患者中的9位在种植体植入的同期接受了自体牙槽骨、粘骨膜移植或人工骨植入手术。根据对种植体周围软组织健康情况、高度、外形和色泽的临床观察,检查种植体及义齿稳定性,结合医、患双方对种植修复体的美观效果、功能状况满意度评价来确定修复效果。结果：12例患者都按期进行了复查,种植义齿修复后咀嚼功能恢复良好,面容和语音功能有显著改观,种植体周围软组织健康。金属烤瓷全冠和修复基台的接缝位于龈下,对接密合,给人以从龈下长出来的视觉效果,美观。11例患者的修复体及其临床应用效果评价为满意,1例评价为可接受。结论：用Replace种植体支持的、螺钉或粘固剂固定的金属烤瓷桥或义齿能够获得医、患双方都满意或可接受的临床应用效果。     

12例重度慢性牙周炎患者全颌种植义齿修复的临床观察

目的探讨对经牙周治疗的重度慢性牙周炎患者拔除剩余牙齿后同期植入种植体并采用全颌种植义齿修复的可行性。方法对12例重度慢性牙周炎患者行牙周治疗，控制病情后，拔除剩余牙齿并同期植入种植体，5～6个月后行全颌种植义齿修复。根据临床、X线检查和患者主诉评价修复效果。结果共计108枚种植体植入20个牙弓，其中37枚种植体即刻植入拔牙窝内。种植体平均承载3年，所有种植体均无松动。2枚种植体发生种植体周围炎，有进行性骨吸收，其中1枚为即刻植入拔牙窝内的种植体。除2枚有进行性骨吸收的种植体外，其余种植体周围的骨吸收高度平均为（1．33±0．10）mm。108枚种植体的存留率为98．1％，37枚即刻种植体的存留率为97．3％。结论对重度慢性牙周炎患者行牙周治疗后拔除剩余牙齿并同期植入种植体，采用全颌种植义齿修复，可减少牙槽骨的吸收、缩短种植修复疗程，在定期的口腔卫生维护下获得理想的修复效果。     

用Replace种植修复体修复上颌前牙缺失

目的：本文报告单独用Replace种植体、或联合邻牙支持和固位的、用粘固剂固定的金属陶瓷单冠修复上颌前牙缺失患者的基本情况、临床修复程序,评价了种植修复体的临床应用效果.方法：用Replace种植体支持的种植单冠为25例患者缺失的31颗上颌前牙进行了修复治疗.22位患者（26枚种植牙）按期复查,其中,10位患者在种植体植入的同期接受了自体组织移植或人工骨植入手术.根据对种植体周围软组织健康情况、附丽高度、外形和色泽的临床观察,结合医、患双方对种植修复体的美观效果、功能状况满意度评价来确定修复效果.结果：种植牙修复后咀嚼功能恢复良好,面容和语音功能有显著改观,种植体周围软组织健康.种植单冠和修复基台的接缝位于龈下,种植牙给人以从龈下长出来的视觉效果,美观.20例按期复查的患者和修复医生对修复体、及其临床应用效果都评价为满意.2例患者对3个种植牙评价为可接受.结论：用Replace种植体支持的、暂时性粘固剂固定的种植上颌前牙能够获得医、患双方都满意或可接受的临床应用效果.     

Aesthetic outcome of single-tooth implant restorations following early implant placement and guided bone regeneration: crown and soft tissue dimensions compared with contralateral teeth

Objectives: The aim of this study was to compare crown and soft tissue dimensions of single-tooth implant restorations following early implant placement and guided bone regeneration (GBR) with contralateral non-restored teeth.
Material and methods: Twenty-seven patients treated by one and the same surgeon and prosthodontist to restore a single-tooth gap with a class I bone defect in the premaxilla by means of an implant-supported restoration were reviewed. Patients were examined at least 6 months following placement of the crown. All implants had been inserted 6–8 weeks following tooth extraction in conjunction with GBR. At evaluation, crown dimensions, soft tissue dimensions, clinical conditions and patients' aesthetic satisfaction were assessed by one clinician who had not been involved in the treatment.
Results: Implant-supported crowns were not significantly longer than contralateral teeth and midfacial soft tissues showed comparable levels after on average 21 months of function. Our data also indicated significant papilla loss especially at the distal aspect of the implants. As the patient's aesthetic appreciation was favourable in 88% of the cases, this appeared to be of trivial importance.
Conclusions: Favourable aesthetics may be achieved for single-tooth implant restorations following early implant placement and GBR. The impact of the latter on papilla levels, however, remains to be determined in longitudinal studies.     

The effect of load cycling on metal ceramic screw-retained implant restorations with unrestored and restored screw access holes

STATEMENT OF PROBLEM: It has been shown that under cyclic loading, more chipping fractures of the veneer ceramic occur on the occlusal surface of screw-retained implant-supported fixed partial dentures (FPDs) with unrestored screw access holes (SAHs) than in cemented restorations. This lack of stability may result in esthetic and functional problems. PURPOSE: The purpose of this study was to investigate whether, under dynamic loading, fewer chipping fractures occur on the occlusal surface of screw-retained ceramic veneered implant FPDs with restored SAHs than in those with unrestored SAHs. MATERIAL AND METHODS: Twenty screw-retained ceramic veneered 5-unit FPDs were manufactured for a 3-implant situation and divided into 2 groups of 10 unrestored and 10 SAHs restored with adhesive composite resin restorations (Tetric Evo Ceram). A masticatory simulator was used to load the FPDs occlusal to the implant positions for 20,000 cycles with a force of 100 N applied for 1 second, followed by 1 second of no loading. Three prosthodontists evaluated the FPDs using a light microscope and a dental probe. The number of chipping fractures found were analyzed using a generalized linear model with Poisson response and log link function (alpha =.05). RESULTS: Investigators found significantly more chipping fractures in the group of screw-retained FPDs with unrestored SAHs. The rate ratio of unrestored versus restored prostheses was 3.29 (P=.006). CONCLUSIONS: Adhesive composite resin restorations can significantly reduce the number of chipping fractures occurring around the SAHs of screw-retained implant-supported restorations.     

Dental occlusion: modern concepts and their application in implant prosthodontics

The aim of this article was to review the literature on various aspects of occlusion related to implant prosthodontics, using PubMed and the Cochrane library. Even if the number of studies on implants and prosthodontics is very large, no randomized controlled trials or Cochrane reviews were found on the possible influence of occlusal design or characteristics of occlusion on treatment outcome. Therefore, studies and articles of a lower evidence level were accepted as the main part of the review. The widely spread opinion that implants are superior to natural teeth was refuted by two recent consensus conferences, which concluded that the long-term outcome of implant restorations is not better than that of natural teeth. No controlled studies on the optimal features of a harmonious natural and/or restored occlusion, including implant prostheses, were found. Nor was there any evidence that more sophisticated methods in jaw registration, e.g., using face-bows and adjustable articulators, compared with simpler methods, will yield better clinical prosthodontic results. This article discusses, among other things, concepts of occlusion of implant-supported restorations, occlusal material, cantilevers, and occlusal risk factors. Within the limitations of the review, it was concluded that many factors can influence implant failure and peri-implant bone loss but that little is known of the relative importance of such factors. Most probably, however, occlusal factors and details of occlusion are in general of minor importance for the outcome of implant restorations. Occlusion can be managed successfully by using simple methods for jaw registration and different occlusal concepts. This article is based on a lecture presented at the Asian Academy of Osseointegration, Hiroshima, Japan, July 18, 2008     

Minimizing the discrepancy between implant platform and alveolar bone for tilted implants with a sloped implant platform: A clinical report

In a patient with edentulism, distally tilted implants with a novel sloped implant platform were used to minimize the discrepancy between the implant platform and alveolar bone crest and to restore complete-arch monolithic zirconia implant-supported fixed prostheses.     

Replacement of mandibular molars with single-unit restorations supported by wide-body implants: immediate versus delayed loading. A randomized controlled study

PURPOSE: This prospective randomized controlled trial aimed to compare single implant-supported mandibular molar restorations using either an immediate or a delayed loading protocol. MATERIALS AND METHODS: Thirty subjects requiring single mandibular molar replacement were consecutively treated. One implant was placed in each patient. Fifteen subjects were assigned to delayed loading protocol and 15 to immediate loading protocol according to a randomization table. After insertion, the delayed loaded implants were connected to a healing abutment and restored after 3 to 4 months of healing without loading. The immediately loaded implants were loaded within 24 hours of surgery with a provisional restoration. The interim prosthesis was placed in centric occlusion. All contacts in lateral excursions were eliminated. At implant placement the maximum value of insertion torque was recorded. Radiographic bone level change was measured on periapical radiographs obtained at the time of implant placement and 12 months after loading. Means of the 2 groups were compared by Student t test and analysis of variance (ANOVA). The level of significance was set at .05. RESULTS: No implants were lost in the delayed loading group (0/15), whereas 1 implant failed (1/15) in the immediate loading group. No differences were observed in relation to implant length or insertion torque between the groups. The average radiographic bone level change after 1 year of function was 1.2 +/- 0.55 mm (range, 0.5 to 2.6 mm) and 0.77 +/- 0.38 mm (range, 0.29 to 1.23 mm) for the delayed loaded and the immediately loaded implants, respectively. The difference in radiographic bone level change between the delayed and immediate loading groups was statistically significant (P = .022; CI = -0.79 to -0.06; Student t test). CONCLUSIONS: Immediate loading of wide-diameter implants supporting single restorations in mandibular molar sites seems to be a suitable clinical option. Moreover, the radiographic bone level change observed after 12 months of loading was significantly less for immediately loaded implants.     

Immediate nonocclusal versus early loading of dental implants in partially edentulous patients: 1-year results from a multicenter, randomized controlled clinical trial

PURPOSE: To compare the efficacy of immediate nonocclusal loading (test group) versus early loading (control group) in partially edentulous patients. MATERIALS AND METHODS: Fifty-two patients in 5 Italian private practices were randomized to 1 of the treatments: 25 to the immediately loaded group and 27 to the early loaded group. To be immediately loaded, single implants had to be inserted with a torque of > 30 Ncm, and splinted implants had to be inserted with a torque of > 20 Ncm. Implants in the immediately loaded group were provided with full acrylic resin nonoccluding temporary restorations within 48 hours after placement. After 2 months, full occluding provisional restorations were provided. Implants in the early loading group were not submerged and were loaded after 2 months. At 8 months, provisional restorations were replaced with definitive metal-ceramic prostheses. Outcome measures were prosthesis and implant failures as well as biologic and prosthetic complications recorded by nonblinded assessors. The Fisher exact test was used to compare the proportion of implant failures. RESULTS: Fifty-two implants were placed in the immediately loaded group and 52 in the early loaded group. No dropouts or complications occurred up to 14 months postinsertion. One single implant failed in the immediately loaded group 2 months after placement. There was no statistically difference for the tested outcome measures between the 2 procedures (P > .99). CONCLUSIONS: The results of this randomized controlled clinical trial with 25 patients rehabilitated with immediately restored nonocclusally loaded implant-supported prostheses compared to 27 patients restored 2 months following placement suggest that there are no major clinical differences in implant survival between these 2 protocols. No biologic or prosthetic complications occurred.     

后牙区螺丝固位与黏结固位种植义齿修复效果的比较研究

目的探讨后牙区螺丝同位与黏结固位种植固定义齿临床修复效果的差异。方法选择上下颌后牙区牙列缺损患者42例共70枚种植体．其中24枚采用螺丝固位修复体．46枚采用黏结周位修复体。分别于修复后1年复诊．检测种植体周围边缘骨吸收量、改良菌斑指数（mPLI）、改良出血指数（mSBI）等临床指标以及患者对种植义齿的美观满意度。结果螺丝固位组及黏结固位组平均种植体周围边缘骨吸收量分别为0．78mm和0．68mm：螺丝组与黏结组mPLI平均水P50均为1，mSBI平均水平P50亦均为1：两组美观满意度平均得分P50为1。统计结果显示螺丝固位组与黏结固位组间种植体周围边缘骨吸收量、mPLI、mSBI以及患者满意度的差异均无统计学意义（P〉0．05）。结论后牙区螺丝固位与黏结固位种植义齿短期临床修复效果差异无统计学意义。     

Treatment outcomes of fixed or removable implant-supported prostheses in the edentulous maxilla. Part I: patients' assessments

STATEMENT OF PROBLEM: Distinct clinical parameters determine whether fixed or removable implant-supported prostheses are indicated to restore the edentulous maxilla. However, there is a strong belief that fixed implant prostheses meet with greater patient acceptance and satisfaction, but this may differ from the patients' perceptions, their psychological responses to treatment, and their assessments of the treatment outcome. PURPOSE: This prospective clinical study compared the treatment outcomes of fixed and removable implant-supported restorations in the edentulous maxilla with the main emphasis on the patient's point of view.Material and methods: Twenty patients who requested an implant-supported superstructure to restore the edentulous maxilla were asked to complete a questionnaire measuring their satisfaction with the present situation and the psychologic impact of their oral health status with their responses marked on a Visual Analog Scale (VAS). Ten patients were treated with a fixed, screw-retained implant prosthesis (group 1), and 10 were treated with a removable, implant-supported and bar-retained overdenture (group 2). Six months after prosthetic rehabilitation, patients were again given the questionnaire to assess their psychologic well-being and satisfaction with the implant-supported restoration. RESULTS: Both prosthesis designs were associated with significant improvements in comfort and retention, function, esthetics and appearance, taste, speech, and self-esteem. No difference was found between the 2 groups with respect to how the patients assessed the implant therapy. However, the results indicated that patients in group 2 experienced greater differences between pretreatment and posttreatment scores for the parameters esthetics, taste, and speech. Treatment costs per unit were significantly higher in group 1 than in group 2. CONCLUSION: Patients in groups 1 and 2 were similarly satisfied with their implant-supported prostheses in the edentulous maxilla with regard to their well-being and the cost-utility, irrespective of whether the restoration was fixed or removable.     

Single implant-supported restorations in the anterior maxilla

Achieving functional and esthetic implant-supported single-tooth restorations in the anterior region of the maxilla can be particularly challenging. Insufficient hard tissue can preclude proper implant positioning, while inadequately treated soft tissue will not exhibit a gingival appearance similar to that of the adjacent teeth. The aims of this article are to analyze the different clinical possibilities (standard and compromised situations) for implant-supported single-tooth restorations in the anterior zone and highlight the importance of knowing the biologic, anatomic, surgical, and prosthetic concepts, particularly the interproximal bone height of adjacent teeth, in the prognosis and predictability of achieving an esthetic result.     

Occlusion patterns of dental arches containing implant-supported restoration

An experimental and clinical study was carried out on 76 patients with implant-supported restorations in the posterior zones of the lower jaw, divided in two groups (with no signs of bone resorption around the implants and with resorption signs) and one control group. The results of the study allowed optimizing the angulation of dental implants, providing an opportunity for individual positioning of dental implant in the mandible depending on the direction of functional load.     

采用分光光度计比较种植支持式氧化锆全瓷和贵金属金瓷修复的牙冠颜色

目的 应用一种小型分光光度计对上前牙区种植支持式氧化锆全瓷修复与贵金属金瓷修复的牙冠颜色进行比较,为临床选择修复材料提供参考依据。方法 纳入 18例（男 7例,女 11例）行口腔种植修复后复查患者的上前牙区种植支持式单冠 29颗进行研究,其中氧化锆全瓷修复单冠 11颗,贵金属金瓷修复单冠 18颗。采用小型反射型分光光度计型比色仪 SpectroShadeTM采集图片并输入计算机,应用相关软件测量每个种植牙冠体 1/3与对照天然牙的CIE L﹡a﹡b﹡颜色差异。应用统计学软件 SPSS 17.0进行统计分析。结果 氧化锆全瓷修复和贵金属金瓷修复的牙冠明度均高于天然牙,全瓷修复引起的明度差异（ 4.5±3.2）大于金瓷修复引起的明度差异（ 1.0±2.6）,具有统计学意义（ P=0.004）;色相差异和饱和度差异均无统计学意义。全瓷修复和金瓷修复与天然牙的颜色差异（ 7.0±2.8和4.0±1.9）均高于人眼的分辨阈值（ 3.7）,且前者差异大于后者,具有统计学意义（ P=0.002）。氧化锆全瓷和贵金属金瓷两种修复方式的临床主观评分无统计学差异（ P=0.977）。上前牙天然牙色由前向后明度渐低,色相变红黄。结论 就本试验所选用的修复材料而言,分光光度计测量显示氧化锆全瓷修复与天然牙的牙冠颜色差异大于贵金属金瓷修复与天然牙的颜色差异,但两种修复方式的临床效果无明显区别。