Fracture behavior of short fiber-reinforced CAD/CAM inlay restorations after cyclic fatigue aging.

The aim of this study was to assess the fracture behavior of molar teeth restored with MOD inlays made of experimental short fiber-reinforced CAD/CAM composite block (SFRC CAD) before and after cyclic fatigue aging. Standardized MOD cavities were prepared on 60 intact mandibular molars. Three groups of CAD/CAM made inlay restorations (Cerasmart 270, Enamic, and SFRC CAD) were fabricated (n = 20/group). All restorations were luted with self-adhesive dual-cure resin cement (G-Cem One). Half of restored teeth per each group (n = 10) were quasi-statically loaded until fracture without aging. The other half underwent cyclic fatigue aging for 500,000 cycles (Fmax = 150 N) before being loaded quasi-statically until fracture. Then, the fracture type was visually inspected. The microstructure and elemental content of CAD/CAM materials were assessed using SEM and EDS. Two-way analysis of variance (ANOVA) was used to statistically examine the data, and it was followed by the Tukey HSD test (α = 0.05). ANOVA demonstrated that both material type and aging had a significant effect (p < 0.05) on the load-bearing capacity values of the restorations. Teeth restored with SFRC CAD showed significantly the highest (p < 0.05) load-bearing capacity (2535 ± 830 N) after fatigue aging among all groups. SEM images showed the ability of short fibers in SFRC CAD composite to redirect and hinder crack propagation. With regard to fracture mode, Enamic group revealed 85% of catastrophic failure (vs. 45% and 10% for Cerasmart 270 and SFRC CAD, respectively). Large MOD cavities on molar teeth were most favorably restored with SFRC CAD inlays, yielding the highest load-bearing capacity and more restorable failures.

Marginal adaptation of CAD-CAM onlays: Influence of preparation design and impression technique.

STATEMENT OF PROBLEM: Factors that may affect the marginal adaptation of computer-aided design and computer-aided manufacturing (CAD-CAM) restorations include preparation design, impression technique, and CAD-CAM system. The influence of impression technique and preparation design on CAD-CAM partial coverage restorations has not been fully addressed. PURPOSE: The purpose of this in vitro study was to investigate the influence of direct and indirect digital scanning techniques and 2 preparation designs on the marginal adaptation of CAD-CAM onlays. MATERIAL AND METHODS: Two mesio-occlusal buccal onlay preparations with reduction of the mesiobuccal cusp were made: conventional preparation (CP) with a 1.2-mm modified shoulder margin and modified preparation (MP) flat cuspal reduction without shoulder. Virtual models were generated from each preparation by using a digital scanner (BlueCam; Dentsply Sirona) from the plastic teeth (direct digital scan) or from the stone dies (indirect digital scan). Onlays were designed using a CAD-CAM system (CEREC 4.0; Dentsply Sirona), and nanoceramic resin blocks (Lava Ultimate Restorative; 3M ESPE) were milled using the CEREC MCX milling machine. Marginal discrepancy was evaluated using an optical stereomicroscope at ×25 magnification in 18 locations distributed along the margins of the preparation. The data were analyzed by using 3-way ANOVA followed by the Tukey HSD test (α=.05). RESULTS: CP presented a statistically significant reduced average marginal adaptation (59 ±50 µm) than did MP (69 ±58 µm) (P<.001). The Tukey HSD test showed the presence of a significantly larger marginal discrepancy in the mesial and buccal locations of MP when compared with CP. Regarding impression techniques, the buccal location presented the smallest average marginal discrepancy in restorations fabricated with indirect impression when compared with direct impression (42 ±33 µm and 60 ±39 µm) (P<.001). CONCLUSIONS: The results showed that conventional preparation with a modified shoulder margin presented improved marginal adaptation compared with modified preparation with flat cuspal reduction. Direct and indirect digital scanning techniques produced restorations within a clinically acceptable range; however, the indirect scanning technique resulted in the fabrication of restorations with superior marginal adaptation on the buccal location.

Evaluation of marginal leakage after mechanical fatigue cycling of composite inlays luted with different cements.

This in vitro study evaluated the marginal microleakage of composite inlays luted with 3 different cement systems. The null hypothesis was that the luting materials would not influence dye penetration, showing the same degree of microleakage. Thirty-six sound molars were selected, mesio-occlusodistal cavities were prepared, and the teeth were randomly divided into 3 groups (n = 12). Composite resin inlay restorations were made and cemented using a dual-curing resin cement (Calibra), a light-curing flowable composite (Charisma Flow), or a self-adhesive resin cement (RelyX Unicem). The restored teeth were subjected to fatigue cycles and immersed in 0.5% basic fuchsin dye for 24 hours. Two orthogonal cuts were made to enable evaluation of dye penetration at the cervical and occlusal margins. The sections were evaluated with a 4-point scale ranging from 0 (no penetration) to 3 (penetration up to the cavity floor [occlusal margins] or axial wall [cervical margins]). The Calibra and Charisma Flow groups showed greater microleakage, notably at the cervical margins, whereas RelyX Unicem specimens showed the least dye penetration. Significant differences were found between the Calibra and Charisma Flow groups and between the Charisma Flow and RelyX Unicem groups (P < 0.05). No statistically significant differences were detected between the Calibra and RelyX Unicem groups. The microleakage associated with the flowable composite was significantly greater than that associated with both resin cements, results that discourage its use for luting of Class II composite inlays.

Effect of cavity design on the fracture resistance of zirconia onlay ceramics.

OBJECTIVE: The purpose of this study was to evaluate the fracture resistance and failure modes of onlay restorations prepared with different preparation designs. MATERIALS AND METHODS: A total of 42 extracted, mandibular first molars (36, 46) were used and divided into six groups according to preparation design, as follows 1A: Anatomic preparation of cusps/rounded shoulder margin/occlusal groove; 1B: Flat preparation of cusps/rounded shoulder margin/occlusal groove; 2A: Anatomical preparation of cusps/occlusal groove; 2B: Flat preparation of cusps/occlusal groove; 3A: Complete anatomical reduction of cusps/rounded shoulder margin; 3B: Complete flat reduction of cusps/rounded shoulder margin groups; intact tooth: No preparation. Onlays were constructed with 0.5-mm copings of Zirconia ceramic. The copings were veneered with porcelain (IPS e. max Ceram). All samples were subjected to fracture resistance testing. Data were analyzed with Kruskal-Wallis and Bonferroni-Dunn tests. RESULTS: Fracture resistance varied significantly according to preparation design. Among the anatomic occlusal preparation designs, fracture resistance was significantly lower in Group 3 when compared to Groups 1 and 2 (P < 0.05). Among the flat occlusal preparation designs, fracture resistance was significantly higher in Group 1 when compared to Groups 2 and 3 (P < 0.05). CONCLUSION: Preparation design affected the fracture resistance of onlay restorations. Cavities with flat occlusal preparation designs, a groove and shoulder margins (1B) resulted in the highest fracture resistance, whereas teeth prepared with a complete reduction of cusps and shoulder margins (3A) had the lowest fracture resistance.

Sequential healing of onlay bone grafts using combining biomaterials with cross-linked collagen in dogs.

OBJECTIVES: The aim of this study was to observe the sequential healing of onlay grafts in terms of the volumetric and histologic changes using different bone substances and absorbable membranes according to the presence of collagen cross-linking. MATERIAL AND METHODS: Four groups involving onlay grafting with different materials were randomly assigned to both sides of the maxillae of 15 beagle dogs: (i) control group without any treatment; (ii) group NN, bovine hydroxyapatite incorporated into a non-cross-linked collagen matrix (BHC) + non-cross-linked collagen membrane (NCCM); (iii) group NC, BHC + cross-linked collagen membrane (CCM); and (iv) group CC, porcine hydroxyapatite incorporated into a cross-linked collagen matrix + CCM. Radiographic and histological analyses were performed after three different healing periods: 4, 8 and 12 weeks. RESULTS: At week 4, the bone substances were well localized under the barrier membrane in groups NC and CC, while the bone substances became spread out and flattened in group NN. Similarly, the augmented height was significantly greater in groups NC and CC (2.55 and 2.51 mm, respectively; median) than in group NN (1.96 mm, P < 0.001, both). The percentages of newly formed bone were significantly higher at week 12 than at weeks 4 and 8 in all of the groups. The NCCM showed an earlier angiogenesis pattern than the CCM; however, earlier degradation was observed at week 12. CONCLUSION: Combining biomaterials with cross-linked collagen might contribute to maintaining its initial morphology with excellent biocompatibility in early healing period of lateral onlay grafts.

Demineralized Xenogenic Dentin and Autogenous Bone as Onlay Grafts to Rabbit Tibia.

PURPOSE: The present study was undertaken to evaluate the healing pattern of xenogenic demineralized dentin onlay grafts in comparison with autogenous bone grafts to the rabbit tibia. MATERIAL AND METHODS: Eight 6-month-old New Zealand male rabbits were used in the experiments. Standardized sized dentin blocks from human premolars and similar autogenous bone blocks harvested from tibia were grafted as onlay blocks on each tibia (n = 8 × 2). All animals were killed after a healing period of 12 weeks. RESULTS: Healing was uneventful for all animals. In general, both the dentin and bone block grafts were fused to the bone, resorbed, and replaced by bone and connective tissue to a varying degree. Both types of grafts were still present after 12 weeks, on an average to approximately one third of the original sizes. Resorption cavities could be seen in the dentin with bone formation. Zones of osseous replacement resorption of the dentin could be noted. In both graft types, higher rate of bone formation was seen at the interface between graft and recipient site. CONCLUSION: Demineralized xenogenic dentin onlay grafts showed similar resorption characteristics as autogenous bone onlay grafts, being resorbed in a similar rate during 12 weeks. New bone formation occurred mainly in terms of replacement resorption in the interface between dentin/bone graft and native bone.

Minimally invasive prosthetic restoration of posterior tooth loss with resin-bonded, wing-retained, and inlay-retained fixed dental prostheses fabricated from monolithic zirconia: A clinical report of two patients.

The esthetics and biocompatibility of ceramic resin-bonded fixed dental prostheses (RBFDPs) are regarded as better than those of their metal ceramic counterparts. However, a high incidence of complications in the posterior arches of ceramic RBFDPs initiated a process of continuous and evolving design development. This clinical report describes 2 successful restorations of a missing posterior tooth with monolithic zirconia RBFDPs with 2 different retainer designs: retentively prepared adhesive wings and inlays.

Clinical Evaluation of Indirect Composite Resin Restorations Cemented with Different Resin Cements.

PURPOSE: To clinically evaluate the performance of indirect composite resin restorations cemented with conventional and self-adhesive resin cements over a 12-month period. MATERIALS AND METHODS: Ten patients fulfilled all the inclusion criteria. Twenty-four composite resin restorations were performed using an indirect technique and cemented with a resin cement (RelyX ARC) or a self-adhesive resin cement (RelyX U100). Two independent evaluators analyzed the restorations using modified USPHS criteria after periods of two weeks and 6 and 12 months. Statistical significance between the cements at each timepoint was evaluated with the Wilcoxon test and between timepoints with the Mann-Whitney test, both at a significance level of 5%. Fisher's exact test was used to assess the occurrence of absolute failures. RESULTS: No statistically significant differences were found between the groups at the same timepoint nor between groups at different timepoints. The only significant difference was found for color match for both groups after 12 months. CONCLUSION: After 12 months, indirect composite resin restorations cemented with self-adhesive resin cement performed similarly to those cemented with conventional resin cement.

Effect of surface treatment and aging on bond strength of composite resin onlays.

STATEMENT OF PROBLEM: Additional polymerization of indirect composite resins enhances their physical properties but lessens the potential for chemical bonding. PURPOSE: The purpose of this in vitro study was to evaluate the influence of different surface treatments and 6-month water storage on the microtensile bond strength (µTBS) of composite resin onlays. MATERIAL AND METHODS: Composite resin onlays (Filtek Z250) randomly received 6 different surface treatments: (1) airborne-particle abrasion with 27-µm alumina particles+Adper Scotchbond 1XT adhesive application, (2) airborne-particle abrasion with alumina particles+silane application (ESPE SIL)+Adper Scotchbond 1XT, (3) airborne-particle abrasion with alumina particles+Scotchbond Universal adhesive, (4) tribochemical silica coating with 30-µm particles (CoJet Sand)+Adper Scotchbond 1XT adhesive, (5) tribochemical silica coating+silane application+Adper Scotchbond 1XT, and (6) tribochemical silica coating+Scotchbond Universal adhesive. Onlays were luted to fresh composite resin specimens with RelyX Ultimate resin cement. Bonded assemblies were stored in water for 24 hours or 6 months at 37°C and subjected to the µTBS test. Additional surface-treated composite resin onlays were analyzed with a contact profilometer to determine average roughness, and micromorphologic changes were analyzed with scanning electron microscopy. RESULTS: Airborne-particle abrasion with alumina followed by Adper Scotchbond 1XT or Scotchbond Universal adhesive application provided the highest bond strength values at 24 hours. Lower values were obtained after tribochemical silica coating. After 6 months of artificial aging, airborne-particle abrasion with alumina or silica-coated alumina particles followed by Scotchbond Universal application yielded the greatest bond strength results. Airborne-particle abrasion with alumina produced the highest roughness values and a more irregular surface. CONCLUSION: Adhesive selection seems to be relevant to the µTBS of luted composite resin onlays after 6 months of water aging, as specimens treated with Scotchbond Universal, after alumina airborne-particle abrasion or tribochemical silica coating, yielded the highest values and better aging stability.

Considerations for Altering Preparation Designs of Porcelain Inlay/Onlay Restorations for Nonvital Teeth.

PURPOSE: The aim of this study was to compare all ceramic inlay/onlay survival rates in vital and nonvital teeth having the same cavity design. Filling the pulp chamber with ceramic materials or not was also discussed. MATERIALS AND METHODS: Ceramic class II inlays/onlays were made on 11 premolars and 30 molars: 14 vital, 27 endodontically treated. The same tooth preparation design was performed on vital and nonvital teeth: In nonvital teeth the pulp chambers were covered by a glass ionomer cement until the pulpal floor depths were between 2 and 2.5 mm, more likely similar to the vital teeth preparations. In vital teeth, glass ionomer was used as a liner to achieve pulpal floor depths between 2 and 2.5 mm when needed. The restorations were assessed (at baseline, 6 months, 1 and 2 years) according to three criteria: marginal discoloration, marginal integrity, and fracture of teeth/restorations, consistent with United States Public Health Service (USPHS) criteria. RESULTS: Eight teeth (19%) showed minor marginal discolorations, while three molars (7%) had loss of marginal integrity. These margins were adjusted using rubber polishing cups and were then judged clinically acceptable. From these three molars, one was vital and two were endodontically treated. No fracture of teeth or restorations was observed. Chi square and exact probability tests were used. There was no statistical difference between vital and nonvital teeth (p = 0.719 chi-squared and Fisher) or between premolars and molars (p = 0.564 chi-squared; 1.000, Fisher). CONCLUSION: Within the limitations of this study there was no difference for the same inlay/onlay cavity design between vital and nonvital teeth. In nonvital teeth, it seems that filling the pulp chamber with a ceramic core material is not important. Long-term observation periods are needed to reinforce the clinical behavior outcome.

Posterior atrophic mandible rehabilitation with onlay allograft created with CAD-CAM procedure: a case report.

AIM: Implant rehabilitation of the atrophic right posterior mandible in a 48-year-old woman using dehydrated homologous bone block, shaped with a computer aided design-computer aided manufacturing (CAD-CAM) system, to avoid harvesting of autologous bone block and to assure a perfect fitting of the block above the alveolar crest. RESULTS: After 7 months, 6.09, 7.36, and 8.08 mm (mean, 7.18 mm) of total horizontal bone gain was observed at sites 6, 12, and 18 mm posterior to the right mental foramen, respectively. CONCLUSIONS: The use of a bone block with CAD-CAM system for alveolar ridge augmentation is a valuable alternative to autograft because it reduces time, cost, and complications for the patients. Data from a computerized tomographic scan can be used to shape a precise 3-dimensional homologous bone block using a CAD-CAM system.

Utilization of iTero digital impression unit for resin composite inlay.

Historically, traditional elastomeric impression techniques for indirect fixed procedures have presented challenges for the operator, laboratory, and patient. Recent digital impression unit technology offers a compelling alternative to elastomeric impressions. The iTero system applies parallel confocal imaging to create a virtual impression that can be easily captured, edited, and uploaded electronically to the dental laboratory. Computer-aided design/computer-aided manufacturing technology is applied to the virtual impression to create an unlimited number of identical polyurethane models. This case report is presented from the perspectives of the clinicians and the laboratory technician using an iTero system to treat a left mandibular second premolar with a resin composite inlay.

[Types and colors of 1 374 chair-side CAD/CAM all-ceramic restorations].

PURPOSE: To analyse the types of chairside CAD/CAM all-ceramic restorations and the color range of all-ceramic materials used so as to provide reference for the application of clinical chairside all-ceramic restoration and the color selection of all-ceramic materials. METHODS: IPS e.max CAD prostheses and related data were collected from January 2021 to December 2021 from the Department of Prosthodontics, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine. The number and type of restorations and the color of materials were investigated and analyzed by descriptive statistics. RESULTS: A total of 1 374 restorations were included, of which 624 were crown restorations, accounting for 45.41% of the total restorations. 516 cases were veneer, accounting for 37.55%; 219 were inlays, accounting for 15.94%; fixed bridges were all adhesive bridges, with the least number with only 15 cases, accounting for 1.09%. In terms of the selection of restoration materials, the use rate of low-transparent(LT) ceramic blocks was significantly higher than that of other transparent ceramic blocks. A was the most frequently used ceramic color. The most frequently used porcelain blocks for veneers were LTA2 and LTA1; for inlay were LTA3; for crowns were LTA2 and LTA3. The blocks used in the fixed bridges were all LT, and A3 color was the majority. CONCLUSIONS: Chairside CAD/CAM all-ceramic prostheses made of IPS e.max CAD materials have been widely used in clinical practice. The types of prostheses include veneer, inset, crown and fixed bridge. The most commonly used IPS e.max CAD blocks are LTA2, LTA3 and LTA1. These findings have certain guiding significance for the clinical restoration decision and the reserve of porcelain blocks in primary hospitals.

Comparison of load-fatigue performance of posterior ceramic onlay restorations under different preparation designs.

OBJECTIVE: The objective of this study was to evaluate the load-fatigue performance of posterior ceramic onlay restorations relative to two variables: preparation design (with or without buccal veneers); and the existing amount of tooth structure (non-worn tooth, worn tooth). METHODS: Sixty extracted third molars were divided into five groups. One group received a mesial-occlusal-distal (MOD) gold onlay restoration (control). The other four experimental groups were prepared for ceramic onlay restorations. Two of the groups additionally received 2-mm occlusal reduction to simulate occlusal wear. All restored teeth were subjected to thermocycling prior to fatigue testing. A fatigue load of 150 N was applied on the occlusal surface at a frequency of 1.2 hz, at an angle of 135 degrees to the long axis of the tooth. Specimen failure was defined as the occurrence of crack propagation in the luting cement layer. This was monitored by the strain gauge on the specimen. RESULTS: All specimens restored on worn tooth had significantly lower fatigue failure cycle counts than those of non-worn tooth. The fracture mode analysis revealed that ceramic fracture tended to be demonstrated only in the group of worn tooth groups. CONCLUSIONS: The addition of a buccal veneer component had no significant effect on the load-fatigue performance of posterior ceramic onlay restorations, but the existing amount of tooth structure did have a significant effect on the load-fatigue performance of posterior ceramic onlay restorations. Catastrophic failures (ceramic fracture) occurred only in the group of worn tooth.

[Short-term and long-term effects of all-ceramic onlay on restoration of premolars and its influence on dental function].

PURPOSE: To investigate the short-term and long-term effects of all-ceramic onlay on restoration of premolars and its influence on dental function. METHODS: Ninety-five premolars receiving root canal treatment in People's Hospital of Peking University from January 2017 to January 2018 were enrolled, and randomly divided into two groups based on different repairing methods. Patients in the control group (n=47) received full crown restoration, while patients in the experimental group(n=48) received all-ceramic onlay restoration. The success, survival and failure rates of the teeth were compared. The United States Public Health Service(USPHS) and occlusal function of the prosthesis were compared 6, 12 and 36 months after treatment. The data were processed using SPSS 19.0 software package. RESULTS: The success and survival rate of the experimental group were higher than those of the control group, but without significant difference (P＞0.05). The morphology, marginal integrity, marginal coloration, surface texture, secondary caries, gingival health and proximal contacts showed no significant difference between the two groups 12 months after treatment(P＞0.05). Thirty-six months after treatment, the marginal integrity, marginal coloration and surface texture showed no significant difference between the two groups (P＞0.05), while the morphology, secondary caries, gingival health and proximal contacts were significantly better in the experimental group than in the control group (P＜0.05). The occlusal function between the affected side and contralateral side of both groups showed no significant difference 6, 12 and 36 months after treatment(P＞0.05). CONCLUSIONS: All-ceramic onlay restoration of premolars has high success and survival rate, and good short-term and long-term restoration effect, which is beneficial to improve the occlusal function of the affected teeth.

Fracture Resistance of Root-Canal Treated Premolars Restored with Dentin Replacement Materials: An In-vitro Study.

PURPOSE: Conservative restorations of endodontically treated premolars have yielded mixed results. The present study aimed to compare fracture resistance of endodontically treated premolars with Class II mesial-occlusal cavity preparations, restored with either Smart Dentin Replacement (SDR; Dentsply Sirona) material, Biodentine (Septodont) or ceramic inlays. MATERIALS AND METHODS: Thirty-two extracted premolars were randomly divided into four equal groups (n = 8): Group 1 served as a control group with teeth left intact; teeth in the remaining three groups received root canal treatment followed by a mesio-occlusal cavity preparation. These crowns were restored with: Biodentine in group 2, SDR in group 3 and ceramic inlays in group 4. A computer-controlled Instron universal testing machine subjected all specimens to compressive load until failure. Force at failure and fracture mode (above or below the cementoenamel junction) were recorded. The data were analysed using Fisher's exact test and one-way ANOVA followed by the post-hoc Tukey's test. Statistical significance was set at p < 0.05. RESULTS: The lowest mean load at failure was recorded for the inlay group. Loads at failure were statistically significantly higher for teeth restored with Biodentine than with SDR (p = 0.012) and ceramic inlays (p = 0.007). There were no statistically significant differences between the groups in terms of fracture mode (p = 0.440). CONCLUSION: Endodontically treated premolars with mesial-occlusal cavity preparation restored with Biodentine were more resistant to fracture than those restored with either SDR or ceramic inlays. Biodentine may prove a promising material to restore endodontically treated teeth with one missing proximal wall.

Effect of immediate dentin sealing on the fracture strength of lithium disilicate ceramic onlays.

This study aimed to evaluate the effect of immediate dentin sealing (IDS) on the fracture strength of ceramic onlays when compared with delayed dentin sealing (DDS). Twenty extracted human maxillary premolars were randomly divided into 2 groups according to the dentin sealing technique (n=10). A standardized mesio-occlusal-distal cavity was prepared with reduction of the palatal cusp. The dentin surfaces of the IDS group were immediately sealed after finishing the preparation (before taking impressions, temporization, and 14-day storage at 37°C) using a bonding system (ALL-BOND 3®, ALL-BOND 3® RESIN) and flowable composite (Te-Econom Flow). Impressions were made and temporary restorations were fabricated using PRO-V FILL®. The wax patterns were milled and the onlays were fabricated by heat-pressing technique (IPS e.max Press). After bonding the final restorations with resin cement (Variolink N), the specimens were thermocycled. Fracture strength was measured using a universal testing machine (Testometric M350-10KN) at 1 mm/min until failure occurred. Student's t-test was used to evaluate the results of the fracture strength test. The failure mode was examined using a stereomicroscope. The mean fracture strength in the IDS group (1335 ± 335 N) was statistically significantly higher than that for the DDS group (931 ± 274 N) (p < 0.05). Fracture of the restoration with a small portion of the tooth was the most frequent mode of failure. Within the limitation of this in vitro study, there was an improvement in the fracture strength of ceramic onlays with the use of IDS. However, the ceramic onlays were strong enough to withstand the physiological mastication force in both groups.

[Digital inlaid design based on anatomical characteristics and preliminary implementation of its program].

OBJECTIVE: To explore the technical guideline of inlays computer aided design (CAD) for further development, to test the feasibility of processing for the design results of the technical guideline, and to assist co-operation with automatic inlay CAD software development. METHODS: On the basis of point cloud data of right mandibular first molar of standard crown, we established the coordinate system,the landmarks and lines and the characteristic curves. A dental cast of right mandibular first molar MOD-inlay of an individual normal occlusion was scanned. The following objects were digitized: prepared tooth, neighbor teeth and intercuspal bite record. On the basis of parametric standard crown established in the research, using Surfacer 11.0, we achieved the reconstruction of MOD-inlay by extracting margin line, constructing tissue surface, constructing outer surface and occlusal grinding, then the design result was processed and try-in on the cast. We also developed automatic inlay CAD software based on the guideline of inlay CAD. RESULTS: The guideline of inlay CAD was established, the design results were processed and an automatic inlay CAD software was developed on basis of Surfacer 11.0. CONCLUSION: It is a feasible method to establish technical guideline of inlay based on reverse engineering technology and process its design result, and a automatic inlay CAD software could be developed based on the technical guideline.