Patients' perceptions regarding microimplant as anchorage in orthodontics

OBJECTIVE: To determine patients' expectations, acceptance, and experience of pain with microimplant surgery compared to other orthodontic procedures. MATERIALS AND METHODS: Seventy-eight microimplants were placed in 37 patients as an anchorage unit for orthodontic treatment. Patients were asked to rate anticipated pain and pain experienced with various orthodontic procedures (tooth extraction, insertion of separators, initial tooth alignment, and microimplant surgery) on a visual analog scale (VAS) over a 7-day period. One month after insertion of microimplants, patients were asked to rate their acceptance of the procedure using a structured questionnaire. RESULTS: Unlike other orthodontic procedures, patients expected to experience a significantly higher level of pain with microimplant surgery than they experienced (P < .001). The postoperative pain experienced decreased continuously from day 1 to day 7 for all orthodontic procedures (P < .05). The total area under the curve (AUC) of pain experienced over the 7-day period was significantly larger for initial tooth alignment than for microimplant surgery (P < .05). Most patients were satisfied with the microimplant surgery (76%) and would recommend it to a friend or family member (78%). CONCLUSIONS: Patients tended to overestimate the pain anticipated with microimplant surgery. Patients were accepting of the surgery and would recommend it to others.     

正畸微种植体支抗即刻加载的稳定性研究

目的 本研究通过观察即刻加载的微种植体支抗周围骨界面组织学变化,旨在探索即刻加载是否会影响微种植体支抗的稳定性.方法 本试验选用成年狗1只,16枚正畸用微种植体植入狗的下颌骨后即刻施加1.5 N力,施力9周后狗被处死.骨标本作病理切片后进行组织学观察和测量.结果 微种植体可以承受即刻加载的1.5 N正畸力而无松动.组织学观察显示骨-微种植体界面有骨组织沉积,没有纤维组织生成,即刻加载的正畸力没有影响骨细胞在微种植体表面的沉积.结论 在严格控制植入创伤、加载力量大小的前提下,微种植体的即刻加载是可行的.     

Comparison of the primary stability of orthodontic miniscrews after repeated insertion cycles:: An in vitro study

ObjectivesTo compare the primary stability of miniscrews after repeated cycles of insertion through insertion torque (IT) measurements and resonance frequency analysis (RFA).Materials and MethodsSixty titanium miniscrews were divided into two groups according to the insertion protocol: one with predrilled sites and the other self-drilled into porcine iliac crest bone specimens. Each group had three cycles of reinsertion. After each insertion, the IT and RFA were measured. The IT was measured by using a torque meter, and the RFA was measured using the Osstell ISQ device. A total of five miniscrews of each group were selected for sequential assessment of the morphology of their tip and threads using scanning electron microscopy after each insertion cycle.ResultsNo statistically significant differences were found in the IT values of miniscrews reinserted up to three times in the group with predrilled surgical sites. The IT value increased significantly with the number of reinsertions in the self-drilled group. The RFA value decreased as the number of insertions increased in both groups.ConclusionsUnder the conditions of this in vitro study, reinserting miniscrews deteriorates the integrity of their tip and thread. Reinsertion should be discouraged particularly when insertion sites are not predrilled.     

Microimplant-based mandibular advancement therapy for the treatment of snoring and obstructive sleep apnea: a prospective study

Objective:To investigate the efficacy of orthodontic microimplant–based mandibular advancement therapies for the treatment of snoring and obstructive sleep apnea (OSA) in adult patients.Materials and Methods:Ten adult OSA patients (seven men, three women; mean age 60.00 ± 9.25 years) were each treated with two mandibular orthodontic microimplants attached to a customized reverse face mask for mandibular advancement. Pretreatment and posttreatment outcome measures of microimplant mobility, apnea-hypopnea index, snoring, respiratory movement, and Epworth sleepiness scores were evaluated after 6 months.Results:Highly significant reductions in the apnea-hypopnea index, snoring, and sleep variables were observed. Sixteen of the 20 (80%) microimplants were stable and showed no mobility, and four (20%) demonstrated grade 1 or 2 mobility and required removal and reinsertion of a new microimplant.Conclusions:Favorable reductions in sleep variables highlight the potential of microimplant-based mandibular advancement therapy as an alternative treatment modality for OSA patients who cannot tolerate continuous positive airway pressure and oral appliance therapy.     

钛合金/不锈钢微植体支抗稳定性的组织学研究

目的:评估钛合金和不锈钢微植体支抗即刻负载的稳定性。方法:选用8只本地成年雄性犬,每只犬任选一侧上颌骨和对侧下颌骨各植入1枚钛合金和不锈钢微植体。同颌2枚微植体间即刻加载1.96 N的力。4周和12周时各随机处死4只实验犬,制作硬组织切片进行组织学研究。结果:所有微植体均没有松动、脱落。微植体与周围组织有良好的生物相容性,种植体周围有纤维组织和骨组织共同包绕。骨结合率随着愈合时间的延长而增高,钛合金微植体骨结合率高于不锈钢微植体。结论:即刻负载下,钛合金和不锈钢微植体支抗的愈合形式都是纤维骨性结合,均可保持稳定,钛合金微植体更为稳定。     

Biomechanical characteristics and reinsertion guidelines for retrieved orthodontic miniscrews

Objectives:To analyze morphological variations of retrieved orthodontic miniscrews and to evaluate the mechanical properties that may adversely affect relocation of miniscrews.Materials and Methods:Retrieved miniscrews were classified with scanning electron microscopy according to the degree of morphological deformation of the tip. To evaluate the differences in mechanical characteristics during reinsertion, changes in insertion torque, insertion time and differences in successful insertion load were compared between unused controls and retrieved miniscrews. In addition, surface composition analysis of retrieved miniscrews was performed using energy-dispersive x-ray spectroscopy.Results:Significant tip deformation was evident in the majority (>84.5%) of retrieved miniscrews. Initial conditions such as insertion site or duration of insertion were not associated with the presence of tip deformation. Insertion load for successful bone penetration increased in proportion to the degree of tip deformation; however, serial changes in insertion torque were similar to those of the controls. Deposited debris such as carbon, calcium, and phosphorus was noted on the retrieved miniscrews.Conclusion:Miniscrews retrieved after primary insertion exhibited decreased cutting ability due to deformation of the tip structure, as well as surface contamination.     

The use of microimplants in orthodontic anchorage.

PURPOSE: Various types of temporary implants have been introduced to serve as orthodontic anchorage. The hypothesis of this study is that microimplants of 1.2 mm diameter can be used as orthodontic anchors, and that their success is related to their length. The aim of this study is to determine the incidence of anchor retention after orthodontic force application for moving teeth, and to determine the relationship of microimplant length to retention rate. METHODS: Fifty-nine microimplants (diameter: 1.2 mm) were placed in 29 patients as orthodontic anchorages. After 2 weeks of microimplant placement, a force of 100 to 200 g was loaded with an elastometric chain or NiTi coil spring. Risk factors were characterized as to why a microimplant may fail, and Fisher's exact test was used for statistical analysis. RESULTS: Nine microimplants were removed and the overall success rate was 84.7%. Exploring the causes for failure, we found significant differences between the length of microimplants and success rate; 6 mm was 72.2% and 8 mm was 90.2%. CONCLUSIONS: The results suggest that microimplants are suited as an alternative orthodontic anchorage. We recommend that 8-mm microimplants are preferable to 6-mm.     

A randomized clinical 1‐year trial comparing two types of non‐submerged dental implants

Objectives: This study compared the implant stability and clinical outcomes obtained with two types of non‐submerged dental implants that have different thread designs and surface treatments. Materials and methods: A randomized clinical trial with 1 year of follow‐up was performed on 56 participants with 75 implants (control group, 36 implants in 28 subjects; experimental group, 39 implants in 28 subjects). The experimental group received the Osstem SSII Implant system; the control group received the Standard Straumann^® Dental Implant System. The diameter and length of the fixture were uniform at 4.1 mm and 10 mm and all the implants restored the unilateral loss of one or two molars from the mandible. To compare implant stability, the peak insertion torque, implant stability quotient (ISQ), and periotest value (PTV) were evaluated during surgery, and at 4 and 10 weeks after surgery. To compare marginal bone loss, standard periapical radiographs were obtained during surgery, and at 10 weeks and 1 year after surgery. Results: This study showed statistically significant differences between the two groups in peak insertion torque (P=0.009) and ISQ (P=0.003) but not in PTV (P=0.097) at surgery. In contrast, there was no statistically significant difference in the pattern of change of ISQ during the 10 weeks after surgery (P=0.339). For marginal bone loss, no significant difference was observed between the control and the experimental groups before functional loading (P=0.624), but after 1 year of follow‐up, a borderline difference was observed (P=0.048). Conclusion: The success rate after 1 year of follow‐up was 100% for both implant system despite the presence of a significant difference in implant stability during surgery. There was a borderline difference in marginal bone loss after 1 year of follow‐up. To cite this article:
Park J‐C, Ha S‐R, Kim S‐M, Kim M‐J, Lee J‐B, Lee J‐H. A randomized clinical 1‐year trial comparing two types of non‐submerged dental implant.
Clin. Oral Impl. Res. 21 , 2010; 228–236.
doi: 10.1111/j.1600‐0501.2009.01828.x     

Radiographic and surgical template for placement of orthodontic microimplants in interradicular areas: a technical note

PURPOSE: In recent years, microimplants have gained popularity in orthodontics. Microimplants are primarily placed in complex sites where critical anatomic structures, such as roots of teeth, may be damaged, so precise surgical planning is required prior to placement. The goal of this report was to introduce a newly developed technique for the placement of microimplants in interradicular areas and evaluate its accuracy. MATERIALS AND METHODS: The planned placement site is radiographed using a radiographic template and film holder fabricated by the investigators. The resultant radiograph is clipped and attached to the radiographic template to make a surgical template to guide the placement of the microimplant. Forty-one patients, 15 men and 26 women ranging in age from 21 to 29 years, were enrolled in this study. On 1 side of the arch, this novel technique was used for implant placement, and on the other side, an established method reported by Maino and associates (i.e., the control technique) was used. RESULTS: A total of 116 microimplants 2 mm wide and 9 mm long were placed interradicularly in 41 patients. Twelve of 58 microimplants were placed unsuccessfully in the control group, versus 2 of 58 in the test group. Statistical analysis showed that there was a significant difference between the 2 techniques in terms of success rate (P < .05). DISCUSSION: Presurgical diagnosis of bone quantity and transfer of the information to the surgical sites are vital in microimplant placement. Radiographic templates modified for surgical purposes have the advantage of transferring radiographic information directly to the surgical site. CONCLUSION: This study, although limited in some respects, demonstrated that microimplant placement can be improved using the newly developed technique described.     

Nanoporous TiO2 Thin Film on Titanium Oral Implants for Enhanced Human Soft Tissue Adhesion: A Light and Electron Microscopy Study

Background: Previous experimental studies have demonstrated direct soft tissue attachment for nanoporous titanium dioxide (TiO₂) thin film on implants, while implants without TiO₂ thin film have not shown this capability. Purpose: The aims were to evaluate and compare TiO₂ surface‐modified experimental microimplants with unmodified microimplants with respect to tissue interaction of the human oral mucosa evaluated by light microscopy on ground sections and semithin sections and transmission electron microscopy on ultrathin sections, and to characterize the inflammatory response and the level of the marginal bone resorption. Materials and Methods: The study was a single‐center, randomized, comparative, clinical investigation with intrasubject comparison of implants with and without TiO₂ thin film in 15 patients. Results: Two comparator microimplants showed mild erythema and expulsion of fluids. The surrounding tissues around all test implants were clinically healthy. The oral mucosa in contact with the abutment part of the microimplant was 72% for the test implants and 48% for the comparator implants, a statistically significant difference (p = .0268). No statistically significant difference was found in other histological variables. The marginal bone loss in 14 weeks was 0.5 mm for the stable test (n = 11) and 1.7 mm for the stable comparator implants (n = 9; p = .0248). Conclusions: The nanoporous TiO₂ surface modification has potential clinical benefits because of increased adherence of soft tissue and possible reduced bone resorption.     

The perception of pain following interdental microimplant treatment for skeletal anchorage: a retrospective study

During orthodontic therapy, patients frequently complain about pain and discomfort, especially during insertion of fixed appliances. Skeletal anchorage using an interdental microimplant is a new concept in orthodontic treatment. The purpose of this study was to investigate differences and changes in the level of pain among patients in relation to orthodontic microimplant treatments. Forty microimplants were applied to the maxilla as skeletal anchors in the orthodontic treatment. The visual analog scale (VAS) was used to evaluate the patients’ perception of pain during this new modality treatment. The premolar extraction VAS core was used as a baseline for the complete orthodontic procedure. The mean VAS score was 35.8 mm at 24 h after premolar extraction. The mean VAS score for insertion and removal of the microimplant 24 h after the operation was 12.3 and 7.8 mm, respectively. Three months after removal of the skeletal anchors, the VAS score had decreased to 3.2 mm and was the same as with the traditional orthodontic treatment. By using the repeated-measure general linear model (GLM), we found that the score 1 day after microimplant placement was significantly less than that 1 day after first premolar extraction or that 1 day after fixed appliance insertion. This result indicates that interdental microimplant did not generate any greater pain than other orthodontic procedures. Therefore, patients were willing to adopt the new orthodontic treatment.     

Is trabecular bone related to primary stability of miniscrews?

Objective: To compare the primary stability of miniscrews inserted into bone blocks of different bone mineral densities (BMDs) with and without cortical bone, and investigate whether some trabecular properties could influence primary stability.Materials and Methods:Fifty-two bone blocks were extracted from fresh bovine pelvic bone. Four groups were created based on bone type (iliac or pubic region) and presence or absence of cortical bone. Specimens were micro-computed tomography imaged to evaluate trabecular thickness, trabecular number, trabecular separation, bone volume density (BV/TV), BMD, and cortical thickness. Miniscrews 1.4 mm in diameter and 6 mm long were inserted into the bone blocks, and primary stability was evaluated by insertion torque (IT), mini-implant mobility (PTV), and pull-out strength (PS).Results:Intergroup comparison showed lower levels of primary stability when the BMD of trabecular bone was lower and in the absence of cortical bone (P ≤ .05). The Pearson correlation test showed correlation between trabecular number, trabecular thickness, BV/TV, trabecular BMD, total BMD, and IT, PTV, and PS. There was correlation between cortical thickness and IT and PS (P ≤ .05).Conclusion:Cancellous bone plays an important role in primary stability of mini-implants in the presence or absence of cortical bone.     

The effect of the thread depth on the mechanical properties of the dental implant

PURPOSE

This study aimed to evaluate the effect of implant thread depth on primary stability in low density bone.

MATERIALS AND METHODS

The insertion torque was measured by inserting Ti implants with different thread depths into solid rigid polyurethane blocks (Sawbones) with three different bone densities (0.16 g/cm³, 0.24 g/cm³, and 0.32 g/cm³). The insertion torque value was evaluated with a surgical engine. The static compressive strength was measured with a universal testing machine (UTM) and the Ti implants were aligned at 30° against the loading direction of the UTM. After the static compressive strength test, the Ti implants were analyzed with a Measurescope.

RESULTS

The Ti implants with deeper thread depth showed statistically higher mean insertion torque values (P<.001). Groups A and group B had similar maximum static compressive strengths, as did groups C and D (P>.05). After the static compressive strength, the thread shape of the Ti implants with deeper thread depth did not show any breakage but did show deformation of the implant body and abutment.

CONCLUSION

The implants with deeper thread depth had higher mean insertion torque values but not lower compressive strength. The deep threads had a mechanical stability. Implants with deeper thread depth may increase the primary stability in areas of poor quality bone without decreasing mechanical strength.     

The effect of implant design on insertion torque and immediate micromotion

Objectives: To evaluate the effect of insertion torque on micromotion to a lateral force in three different implant designs. Material and methods: Thirty‐six implants with identical thread design, but different cutting groove design were divided in three groups: (1) non‐fluted (no cutting groove, solid screw‐form); (2) fluted (90° cut at the apex, tap design); and (3) Blossom^? (Patent pending) (non‐fluted with engineered trimmed thread design). The implants were screwed into polyurethane foam blocks and the insertion torque was recorded after each turn of 90° by a digital torque gauge. Controlled lateral loads of 10 N followed by increments of 5 up to 100 N were sequentially applied by a digital force gauge on a titanium abutment. Statistical comparison was performed with two‐way mixed model ANOVA that evaluated implant design group, linear effects of turns and displacement loads, and their interaction. Results: While insertion torque increased as a function of number of turns for each design, the slope and final values increased (P<0.001) progressively from the Blossom^? to the fluted to the non‐fluted design (M±standard deviation [SD]=64.1±26.8, 139.4±17.2, and 205.23±24.3 Ncm, respectively). While a linear relationship between horizontal displacement and lateral force was observed for each design, the slope and maximal displacement increased (P<0.001) progressively from the Blossom^? to the fluted to the non‐fluted design (M±SD=530±57.7, 585.9±82.4, and 782.33±269.4 μm, respectively). There was negligible to moderate levels of association between insertion torque and lateral displacement in the Blossom^?, fluted and non‐fluted design groups, respectively. Conclusion: Insertion torque was reduced in implant macrodesigns that incorporated cutting edges, and lesser insertion torque was generally associated with decreased micromovement. However, insertion torque and micromotion were unrelated within implant designs, particularly for those designs showing the least insertion torque. To cite this article:
Freitas AC Jr, Bonfante EA, Giro G, Janal MN, Coelho PG. The effect of implant design on insertion torque and immediate micromotion.
Clin. Oral Impl. Res. 23 , 2012; 113–118.
doi: 10.1111/j.1600‐0501.2010.02142.x     

Mechanical Performance and Metallurgical Features of ProTaper Universal and 6 Replicalike Systems

IntroductionThis study aimed to compare the ProTaper Universal (PTU; Dentsply Maillefer, Ballaigues, Switzerland) system with 6 replicalike instruments regarding instrument design, mechanical performance, and alloy characteristics.MethodsNew rotary instruments (size 20/.07v) of PTU and 6 replicalike systems (EdgeTaper [EdgeEndo, Johnson City, TN], U-File [Dentmark, Ludhiana, India], Go-Taper Universal [Access, Shenzhen, China], Super Files [Flydent, Shenzhen, China], Multitaper [Proclinic Expert, Besançon, France], and Pluri Taper [Bestdent, Shenzhen, China]) (n = 329) were selected and evaluated regarding their design, mechanical performance, and metallurgical characteristics. The results were compared using the nonparametric Mood median test and 1-way analysis of variance with the significance level set at 0.05.ResultsReplicalike instruments were similar to PTU regarding design, maximum torque to fracture (P > .05), and ratio of nickel and titanium elements. Scanning electron microscopy revealed differences in the geometry of the tip and finishing surfaces. Time to fracture of Go-Taper Universal (50.0 seconds) was similar to PTU (44.0 seconds) (P > .05), but the U-File (63.5 seconds), Edge Taper (87.5 seconds), and Super Files (130 seconds) showed significantly higher values (P < .05). The highest maximum torque was observed in the Super Files instrument (P < .05), but no statistical difference was noted among the other instruments (P > .05). The angle of rotation before rupture of the Multitaper (574°) and Pluri Taper (481°) was higher than PTU (354°) (P < .05). Differential scanning calorimetric analysis showed clear differences on the transformation temperatures among the tested instruments. The R-phase start and finish temperatures of PTU were 11.0°C and −18.0°C, respectively.ConclusionsOverall, replicalike instruments were similar to PTU regarding the torsional resistance, geometric design, and near equiatomic proportions of nickel and titanium elements. In 3 of the 4 mechanical tests, the EdgeTaper (torque, angle of rotation, and bending load) and Go-Taper Universal (time to fracture, torque, and angle of rotation) systems were similar to PTU.     

Effects of insertion angle and implant thread type on the fracture properties of orthodontic mini-implants during insertion

Objective:To determine the effects of insertion angle (IA) and thread type on the fracture properties of orthodontic mini-implants (OMIs) during insertion.Materials and Methods:A total of 100 OMIs (self-drilling cylindrical; 11 mm in length) were allocated into 10 groups according to thread type (dual or single) and IA (0°, 8°, 13°, 18°, and 23°) (n  =  10 per group). The OMIs were placed into artificial materials simulating human tissues: two-layer bone blocks (Sawbones), root (polymethylmethacrylate stick), and periodontal ligament (Imprint-II Garant light-body). Maximum insertion torque (MIT), total insertion energy (TIE), and peak time (PT) were measured and analyzed statistically.Results:There were significant differences in MIT, TIE, and PT among the different IAs and threads (all P < .001). When IA increased, MIT increased in both thread groups. However, TIE and PT did not show significant differences among 0°, 8°, and 13° IAs in the dual-thread group or 8°, 13°, and 18° IAs in the single-thread group. The dual-thread groups showed higher MIT at all IAs, higher TIE at 0° and 23° IAs, and longer PT at a 23° IA than the single-thread groups. In the 0°, 8°, and 13° IA groups, none of the OMIs fractured or became deformed. However, in the 18° IA group, all the OMIs were fractured or deformed. Dual-thread OMIs showed more fracturing than deformation compared to single-thread OMIs (P < .01). In the 23° IA group, all OMIs penetrated the artificial root without fracturing and deformation.Conclusions:When OMIs contact artificial root at a critical contact angle, the deformation or fracture of OMIs can occur at lower MIT values than those of penetration.     

Optimal force magnitude loaded to orthodontic microimplants: A finite element analysis

Objective:To find an optimal force that can be loaded onto an orthodontic microimplant to fulfill the biomechanical demands of orthodontic treatment without diminishing the stability of the microimplant.Materials and Methods:Using the finite element analysis method, 3-D computer-aided design models of a microimplant and four cylindrical bone pieces (incorporating cortical bone thicknesses of 0.5, 1.2, 2.0, and 3.0 mm) into which the microimplant was inserted were used. Various force magnitudes of 0.5, 1.0, 1.5, 2.0, 2.5, 3.0, 3.5, and 4.0 N were then horizontally and separately applied to the microimplant head as inserted into the different bone assemblies. For each bone/force assembly tested, peak stresses developed at areas of intimate contact with the microimplant along the force direction were then calculated using regression analysis and compared with a threshold value at which pathologic bone resorption might develop.Results:The resulting peak stresses showed that bone pieces with thicker cortical bone tolerated higher force magnitudes better than did thinner ones. For cortical bone thicknesses of 0.5, 1.2, 2.0, and 3.0 mm, the maximum force magnitudes that could be applied safely were 3.75, 4.1, 4.3, and 4.45 N, respectively.Conclusions: For the purpose of diminishing orthodontic microimplant failure, an optimal force that can be safely loaded onto a microimplant should not exceed a value of around 3.75–4.5 N.     

一种微型自攻型支抗钉的设计与制造

目的 研制一种具有良好生物力学功能、可直接自攻到位的微型自攻型支抗钉。方法 选用高强度植入物用钛合金TC4，或316L植入物医用不锈钢，设计支抗钉螺杆尖端自攻、螺杆主体、非骨质埋入部(龈部)、支抗钉功能头部和周向稳定槽，并采用6轴数控加工中心、配专用夹具工艺制造微型自攻型支抗钉。结果 成功设计了一种支抗钉螺杆尖端、螺杆主体骨螺纹和轻锥度、力矩输入段及牵引悬挂结构的微型自攻型支抗钉，该支抗钉能满足多重牵拉结扎，无需通过黏膜切口手术，可直接从牙龈穿透自攻植入牙床骨质中。结论 支抗钉具有良好的植入稳定性、生物相容性，在自攻固位后即可牵拉结扎，有效地缩短了正畸周期，避免了牵引过程中出现植入部分松动或植入部分失效的现象。     

Assessment of damping capacity as an index of root proximity in self-drilling orthodontic mini-implants

Objectives

This study aims to investigate orthodontic mini-implant root proximity, placement torque, and damping capacity and to determine whether placement torque and damping capacity (Periotest value (PTV)) are useful indices for the estimation of mini-implant root proximity.

Materials and methods

The root proximity of 143 orthodontic mini-implants (1.6 mm diameter, 8 mm screw thread length) was evaluated in 79 patients (24 males, 55 females; mean age, 22.5?±?8 years) using cone-beam computed tomography. The placement torque and PTV of each implant were determined using a torque tester and the Periotest, respectively. Variability in these values according to root proximity was evaluated.

Results

PTVs of mini-implants with multiple (two or more) points of contact between the root and implant were significantly larger than those of mini-implants with no root contact in the self-drilling group. Placement torque did not differ significantly according to root proximity. In the self-drilling group, the odds ratio for root contact was 20.82 (P?=?0.000) for a PTV >6.

Conclusions

Placement torque could not be used to estimate root proximity. The PTV was significantly affected by root proximity in the self-drilling group.

Clinical relevance

A threshold of PTV >6 could be applied clinically for the estimation of self-drilling mini-implant root proximity.     

Does bone mineral density influence the primary stability of dental implants? A systematic review

Objective: The aim of this systematic review was to investigate the influence of bone mineral density on the primary stability of dental implants. Material and methods: A search of health science databases (Cochrane Library, MEDLINE‐PubMed, ISI Web of Knowledge, EMBASE, LILACS) and grey literature was performed, including papers published until January 2011. The main key words used were “bone density” (MeSH/DeCS), “dental implant” (MeSH/DeCS), “implant stability”, “implant stability quotient”, “ISQ”, “resonance frequency analysis”, “RFA”, “Osstell”, “Periotest value”, “PTV”, “Periostest”, “insertion torque”, “placement torque”, “cutting torque”. The inclusion criteria comprised observational clinical studies performed in patients who received dental implants for rehabilitation; studies that evaluated the association between bone mineral density and implant primary stability; bone density assessment performed by measurement of Hounsfield units using cone beam computed tomography; and dental implant primary stability evaluated by ISQ value, PTV value or insertion torque measurement. The articles selected were carefully read and classified as low, moderate and high methodological quality, and data of interest were tabulated. Results: Ten articles met the inclusion criteria, but only seven were included because of overlapping patients. They were classified as low or moderate methodological quality and control of bias, and presented positive association between primary stability and bone density. Conclusions: There is a positive association between implant primary stability and bone mineral density of the receptor site. However, the methodological quality and control of bias of the studies should be improved to produce stronger evidences. To cite this article:
Marquezan M, Osório A, Sant'Anna E, Souza MM, Maia L, Does bone mineral density influence the primary stability of dental implants? A systematic review.
Clin. Oral Impl. Res. 23 , 2012; 767–774.
doi: 10.1111/j.1600‐0501.2011.02228.x