Clinical outcome and prosthodontic compensation of tilted interforaminal implants for mandibular overdentures

PURPOSE: The aim of this study was to evaluate the sagittal inclination of interforaminal implants, the clinical implant outcome, and the necessary extent of prosthodontic compensation modalities for implant overdentures (IODs). MATERIALS AND METHODS: Lateral cephalometric radiographs of 62 patients, each with a mandibular IOD retained by 2 to 4 implants, were analyzed. The sagittal inclination of the longitudinal implant axis of the most anterior implant was analyzed relative to the mandibular and occlusal planes. The angle needed to compensate for the inclination of the mandibular implant to obtain Angle's class I for the prosthesis (the compensation angle) was measured and compared with respect to skeletal class. Peri-implant structures were measured using the Plaque Index and the Gingival Index. The compensation angle was correlated with the mandibular implant inclination, the degree of mandibular atrophy, and the anterior facial height. RESULTS: The most anterior mandibular implants showed a mean retroinclination of 74.3 +/- 9.3 degrees in relation to the mandibular plane; retroinclination was significantly more pronounced in skeletal class II than skeletal classes I and III (P < .05). The compensation angle (26.9 +/- 10.5 degrees) was more significant for skeletal class II than for skeletal classes I and III (P < .01). Sagittal mandibular implant inclination correlated significantly to the compensation angle (r = -0.46; P < .05), mandibular atrophy (r = 0.32; P < .05) and mandibular facial height (r = -0.45; P < .05). Implant survival rate and peri-implant parameters (bone loss, pocket-depth, Plaque and Gingival Indices) of the interforaminal implants were not shown to be influenced by implant retroinclination. Nine patients (2 skeletal class 1, 7 skeletal class II) reported phonetic problems with the IOD because of narrowing of the lingual space but described significant improvement after a median 4.7 months (range, 3 to 12 months). DISCUSSION AND CONCLUSION: Depending on skeletal class, prosthetic compensatory mechanisms will be operative in the presence of mandibular implant retroinclination for IOD. Knowledge of mandibular inclinations and the compensatory mechanisms may be an essential factor in successful prosthetic rehabilitation and may provide for a homogenous design of the bar construction and easier handling and may also reduce stress on the attachment mechanism.     

One-year prosthetic outcomes with implant overdentures: a randomized clinical trial

PURPOSE: This randomized clinical trial examined implant overdenture (IOD) fabrication and maintenance time and costs, adjustment and repair incidence, and patient satisfaction after 1 year. MATERIALS AND METHODS: Sixty-four patients received 2 mandibular implants and an IOD with either a bar with 2 clips or 2 ball attachments for denture retention. RESULTS: Fabrication time, number of appointments, and chair time for adjustments were similar for the 2 denture designs. The most common adjustments for both types were to the IOD contours. Ball-attachment dentures required about 8 times longer for repairs than bar-clip prostheses. Approximately 84% of patients with ball-attachment dentures needed at least 1 repair, versus 20% of those with a bar-clip mechanism. The most common repairs were replacement of the cap spring or cap for the ball-attachment IOD and replacement of a lost or loose clip for bar-clip dentures. DISCUSSION: Patients were equally and highly satisfied with the improvements in function, comfort, and appearance with both types of IOD compared to their original conventional dentures. CONCLUSIONS: Given equivalent levels of patient satisfaction with either method of retention and a much higher repair rate for the ball attachment, it is suggested that a bar-clip design be used rather than the particular ball attachment utilized in this study.     

A biomechanical effect of wide implant placement and offset placement of three implants in the posterior partially edentulous region

To prevent loosening or fracture of screws retaining the prosthesis to the implants in the posterior partially edentulous region, the use of staggered buccal and lingual offset placement or wide implants is suggested. However, it is not known how this usage compensates for the torque produced by lateral occlusal forces. This study evaluated the effectiveness of offset placement of three implants and a wide implant placement at the most posterior site. Three-dimensional geometric analysis was used to calculate the tensile force applied to gold screws in clinical situations with buccal or lingual loading perpendicular to cuspal inclination (10 or 20 degrees ). Four variations of the placement of three implants (3.75 mm) are: (1) straight; (2) buccal offset of the second implant; (3) lingual offset of the second implant; (4) a wide implant (5 mm) placement at most posterior site. The offset placement did not always decrease tensile force at the gold screw, but wide implant placement and decrease in cuspal inclination did.     

The effect of the design of a mandibular implant-supported zirconia prosthesis on stress distribution

Statement of problemProsthetic complications have been frequently reported in implant-supported complete-arch prosthesis. Prosthetic restorations designed with an all-on-four treatment concept and fabricated from zirconia ceramic may be used to overcome these problems.PurposeThe purpose of this biomechanical study was to evaluate the effects of cantilever length and inclination of implant on the stress distribution in bone tissue, implant, and a monolithic zirconia ceramic-lithium disilicate glass-ceramic superstructure for all-on-four prosthesis.Material and methodsAll-on-four mandibular prosthesis fabricated from a zirconia and lithium disilicate glass-ceramic (LDGC) superstructure was designed with cantilever lengths of either 5 mm or 9 mm and posterior implants with a distal tilt of either 15 or 30 degrees. Stresses were evaluated with a simulated application of a static load of 600 N.ResultsIncreasing implant inclination from 15 to 30 degrees led to a decrease in maximum principal stress (MaxPS) values of approximately 4 to 7 MPa in cortical bone around all implants except the right anterior implant in the designs with short cantilevers and an increase in MaxPS values (approximately 3 to 19 MPa) in the same places in the designs with the long cantilevers. Increasing cantilever length from 5 to 9 mm resulted in an increase in minimum principal stress (MinPS) values of approximately 3 to 13 MPa in the cortical bone surrounding all posterior implants. In the designs with the long cantilever, MaxPS values increased approximately 3 to 4 MPa in spongy bone adjacent to the right posterior implant. An increase in cantilever length also led to higher vMS values at the first and second implant grooves in the right posterior implant in the design with the 15-degree implant tilt. An increase in implant inclination in the design with the short cantilever resulted in lower vMS values at the apex and all grooves of the left posterior implant, whereas in the design with the long cantilever, an increase in implant inclination resulted in lower stress values in the first and second grooves of the same implant. An increase in implant inclination led to in an increase in vMS values in the core structure.ConclusionsIn zirconia ceramic restorations by using an all-on-four design with an LDGC superstructure, short cantilevers may be preferable because they result in a more favorable distribution of stress than long cantilevers. An increase in implant angulation from 15 to 30 degrees decreased MaxPS values in cortical bone.     

Evaluation of the effect of the residual bone angulation on implant-supported fixed prosthesis in mandibular posterior edentulism. Part II: 3-D finite element stress analysis

Buccolingual angulation of the mandibular posterior edentulous region may affect the prosthetic load conditions, so as to cause high stress concentrated areas that may easily lead to failure. The aim of this study was to evaluate the effect of various predetermined buccolingual angulation values on stress distribution in the mandibular posterior edentulous region restored with implant-supported fixed partial dentures, using three-dimensional finite element analysis. Stress analyses were performed applying 400N oblique force to implant-supported fixed prosthesis. Stress analyses indicated tensile stress values on the buccal surface and compressive stress values on the lingual surface of cortical bone were increased as the angulation of the edentulous bone increased (especially corresponding to the cervical region of the implants). Compressive stress values, observed where two implants were placed at the second premolar and second molar regions (5-7 design) and first and second molar regions (6-7 design), respectively, were very close to or even exceeded the ultimate compressive strength of bone. It is concluded that when a definite buccolingual angulation is added to other existing risk factors such as bruxism, placing an implant for every missing tooth might reduce the high stress concentration areas.     

Biomechanical rationale for intentionally inclined implants in the posterior mandible using 3D finite element analysis

PURPOSE: Since natural dental arches usually form Monson or Spee occlusal curvatures among the posterior teeth, they tend to incline in mesial and lingual directions. The purpose of this study was to examine the biomechanical rationale for placing implants according to these curvatures in the mandibular posterior region. MATERIALS AND METHODS: A 3-dimensional finite element model was created in which 2 implants were placed in the mandibular molar area. Stress distribution in the bone around the implants was analyzed under different distal implant inclinations. RESULTS: Stress in the cervical area of the mesial and distal implants and the surrounding bone was higher when the implants were placed parallel to each other compared to when the distal implant was placed with a mesial or mesiolingual inclination. DISCUSSION: The slightly smaller effect of a mesiolingual inclination compared to a mesial inclination can be explained by the large cantilever on the buccal side of the superstructure. CONCLUSION: Within the limitations of this study, it was suggested that there is a biomechanical rationale for placing implants in the posterior mandible area with a mesial inclination similar to that of natural teeth. It was also suggested that too much lingual inclination can put the implant at risk of overload.     

Dimension of keratinized mucosa and the interproximal papilla between adjacent implants

BACKGROUND: The interproximal papilla between two adjacent implants is gaining critical interest in the implant dentistry. The aims of this study were to evaluate the effect of 1) the width of keratinized mucosa, 2) the distance from the base of the contact point to the crestal bone, and 3) the horizontal distance between two implants on the radiographic dimension from the tip of the papilla to the crestal bone between two implants. METHODS: This study involved 72 interproximal papillae between two adjacent implants (interimplant papilla) in 52 patients who had implants placed adjacent to each other and had a prosthesis in place more than 1 year. The shortest distance between the radiopaque material on the tip of the interimplant papilla and most coronal portion of the interimplant crestal bone was measured (the radiographic length of the papilla [RL]). The width of keratinized mucosa from the tip of the papilla was measured (WK). The vertical distance between the base of the contact point and the interimplant crestal bone was measured (CC). The horizontal distance between the two adjacent implants was measured at the fixture-abutment interface level (HD). Multiple regression analysis was performed between WK-RL, CC-RL, and HD-RL. RESULTS: RL had a significant relation with WK between two adjacent implants (P = 0.001). However, RL was not related with other variables, such as CC and HD (CC, P = 0.641; HD, P = 0.901). CONCLUSION: The results of this study suggest that the width of keratinized mucosa between two adjacent implants might be related to the dimension of the interproximal papilla between two adjacent implants.     

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??Objective    To measure the anatomic buccolingual angulation values of the mandibular alveolar process based on CBCT images in order to help determine the implant angulation at the implant treatment-planning phase. Methods    A random sample of 51 CBCT images were selected and analyzed. The NewTom 5G CBCT data sets were reformatted at a 5-mm spacing??with the inferior border of the region of interest parallel to the base of the mandible. Twenty-four buccolingual cross-sectional images of the mandibular alveolar process of each CBCT scan were obtained for angulation measurements by NNT5.6 software. Results    The mean or median values of the buccolingual angulation of the mandibular alveolar process??ranging from 1.8 degrees to 28.5 degrees??were obtained. There were no statistically significant differences on the angulation values of the alveolar process between the right side and left side or between male and female patients??P??0.05??. The number of buccally-inclined alveolar process cross-sections increased from cross-section NO.8 to NO.11??and decreased from cross-section NO.14 to NO.17??which were statistically significant??P??0.05??. Conclusion    The mean or median values of the buccolingual angulation of mandibular alveolar process increase gradually from the anterior tooth region via the premolar region to the second molar region. Most of the mandibular alveolar process cross-sections at the anterior teeth region incline buccally??while most of those at the premolar region and all of those at the molar region incline lingually. Knowing buccolingual angulation values of the mandibular alveolar process before dental implantation may help the clinician plan the orientation of implants.     

下颌牙槽突颊舌向生理倾斜角锥形束CT影像研究

目的    采用锥形束CT（CBCT）影像测量整个下颌骨牙槽突颊舌向生理倾斜角,为种植手术提供参考。方法      按照事先制定的纳入与排除标准,从中国人民解放军总医院口腔医学中心影像数据库中随机抽取2014年11月至2015年11月初次就诊患者拍摄的CBCT影像51例。采用NewTom 5G自带软件进行重建,重建区域上下边界与下颌骨下缘平行,采用0.5 mm层厚、5 mm层间距,在牙列弧形线上对牙槽突进行垂直切割,获得下颌牙槽突的24个等间距的颊舌向切面。使用NNT 5.6软件测量每个颊舌向切面的牙槽突倾角。结果    从右下颌磨牙区（第2层）到左下颌磨牙区（第23层）,牙槽突倾角均值或中位值分别为-27.6°、-28.5°、-26.2°、-21.7°、-17.7°、-12.9°、-7.4°、-2.8°、2.2°、3.7°、4.8°、5.8°、3.5°、1.8°、-2.5°、-6.9°、-12.0°、-15.7°、-20.0°、-24.9°、-27.0°和-28.2°,负值表示向舌侧倾斜。左右对称层面间和男女之间的牙槽突倾角差异均无统计学意义（均P＞0.05）。第2 ~ 7层、第17 ~ 23层绝大多数牙槽突向舌侧倾斜（P＜0.05）;第8 ~ 11层偏向颊侧牙槽突逐渐增多,第14 ~ 17层偏向颊侧牙槽突逐渐减少（P＜0.05）;第10 ~ 15层偏向颊侧牙槽突数目多于偏向舌侧牙槽突数目,偏向舌侧牙槽突比例为7.8%（4/51） ~ 37.3%（19/51）。结论    下前牙区牙槽突倾角值最小,从前磨牙区至第二磨牙区牙槽突倾角值逐渐增大。前牙区主要向颊侧倾斜,前磨牙区主要向舌侧倾斜,磨牙区均向舌侧倾斜。了解牙槽突倾斜方向和倾角大小有助于种植体植入方向的确定,可为种植手术提供参考作用。     

Dimension of interproximal soft tissue between adjacent implants in two distinctive implant systems

BACKGROUND: The purpose of this study was to compare the dimension of interproximal soft tissue between adjacent implants in distinctive implant systems. METHODS: This study involved 85 interproximal papillae between two adjacent implants in 50 patients who had implants placed adjacent to each other and who had prosthesis in place for longer than 1 year. The shortest distance between the radiopaque material on the tip of interimplant papilla and the most coronal portion of the interimplant crestal bone was measured (radiographic length of papilla [RL]). The horizontal distance (HD) between the two adjacent implants was measured at the fixture-abutment interface level. Considering the possible effect of interimplant crestal bone resorption on closely implanted sites, HDs were divided into two categories: HD <3 and >or=3 mm. The Mann-Whitney test was performed to find the difference in the dimension of interimplant papilla. RESULTS: In cases of HD <3 mm, RL did not differ statistically in both systems. Also, in cases of HD >3 mm, RL did not show a statistically significant difference in both systems. CONCLUSION: Both systems had similar dimensions of interproximal soft tissue between adjacent implants, irrespective of the horizontal distance of the fixture.     

Correction of a malpositioned endosseous implant by a segmental osteotomy: a case report

A mandibular overdenture supported by 2 or 4 endosseous implants has been proven to be a reliable treatment modality for patients suffering from conventional denture problems. However, fabrication of an implant-retained mesostructure to support an overdenture is not possible in all cases. Malpositioning of implants is a common cause of failure in such cases. A case is presented in which a ball attachment caused pain and severe swelling of the floor of the mouth because of the lingual inclination of an endosseous implant. The lingual inclination of the implant was corrected by a segmental osteotomy. Six weeks later, prosthodontic treatment began, and the resultant overdenture supported by a Dolder bar was quite acceptable for the patient.     

Use of cephalometric analysis for implant placement in a patient with an edentulous maxilla with a severe Class III intermaxillary relationship

A patient with a totally edentulous maxilla and a seVere Class III intermaxillary relationship in the anterior region was treated by implants. In the mandible, there were 10 teeth between the second premolars. The inclination and width of the maxillary anterior residual bone were measured on cephalometric X-ray film obtained before treatment. The results of cephalometric analysis did not support clockwise rotation of the mandible or lingual angling of the maxillary anterior teeth by use of prosthesis to improve the Class III relationship. Ten implants were simultaneously placed in the maxilla. Then, a maxillary temporary full bridge was seated after reduction of the crown lengths of the mandibular anterior teeth. An apically positioned flap operation was performed to eliminate periodontal pockets and to obtain clinically suitable crown lengths of the mandibular anterior teeth. A noncemented, screw-retained maxillary full bridge and a conventional mandibular full bridge were placed. Postoperative cephalometric analysis showed that the outcome was clinically acceptable. The patient has been satisfied for more than 5 years since placement of the implant prostheses.     

上部结构材料对无牙下颌种植固定修复影响的三维有限元分析

目的:通过三维有限元方法探讨上部结构材料对无牙下颌种植固定修复生物力学的影响,为无牙颌修复治疗提供参考。方法:构建无牙下颌种植固定修复三维有限元模型,用6种牙科材料（纯钛、钴铬合金、金合金、氧化锆、聚醚醚酮及碳纤维增强聚醚醚酮）分别对种植上部结构进行赋值,得到6种模型,模拟斜向加载,对种植体、周围骨组织及上部结构进行应...     

基于锥形束CT的不同垂直骨面型重度骨性Ⅲ类错牙合成人患者上下前牙冠根成角分析

目的    应用锥形束CT分析不同垂直骨面型重度骨性Ⅲ类错牙合成人患者上下前牙牙冠与牙根所成的角度（冠根成角）,为正畸治疗过程中上下前牙更安全而有效地移动提供参考依据。方法    选取2012年1月至2021年1月于大连市口腔医院正畸科就诊的重度骨性Ⅲ类错牙合成人患者152例,根据下颌平面角分为高角组（53例）、均角组（52例）、低角组（47例）,应用Invivo dental 5.0软件将所有患者的锥形束CT影像进行三维重建,测量并比较各组上下前牙的冠根角（CRA）和面轴角（SSA）。结果    各组上下中切牙冠根成角总的比较,差异均有统计学意义（均P < 0.05）。组间两两比较结果显示,上中切牙CRA和下中切牙SSA由大至小均依次为低角组、均角组和高角组,而下中切牙CRA和上中切牙SSA由大至小均依次为高角组、均角组和低角组,差异均有统计学意义（均P < 0.05）;其中,低角组上中切牙CRA > 180°且SSA为负值。结论    重度骨性Ⅲ类错牙合患者上下中切牙冠根成角在不同垂直骨面型之间有显著差异,其中高角和均角患者上中切牙冠相对牙根向舌侧倾斜,且高角患者更加明显;低角患者上中切牙与之相反,表现为牙冠相对牙根向唇向倾斜。3种骨面型患者的下中切牙牙冠相对牙根均向舌侧倾斜,且下颌平面角越小,其牙冠舌向倾斜越明显。     

Retrieval and replacement of a malpositioned dental implant: a clinical report

This clinical report describes the retrieval of a malpositioned mandibular implant with a severe lingual inclination. A replacement implant was inserted with an emphasis on its relationship with the maxillary antagonist, resulting in a buccal inclination of approximately 10 degrees. The treatment review highlights the importance of thorough communication among all members of the dental implant team.     

Accuracy of two impression techniques with angulated implants

STATEMENT OF PROBLEM: Accurate recording of implant locations is required so that definitive restorations are properly supported and do not place additional stress on the implants. Angulated implants may result in inaccurate impressions, and the impression technique may affect the accuracy of the definitive cast. PURPOSE: The purpose of this study was to determine the effect the combined interaction of impression technique, implant angulation, and implant number has on the accuracy of implant definitive casts. MATERIAL AND METHODS: One definitive stone cast was fabricated for each of 6 experimental groups and 1 control group. All 7 definitive casts had 3 implants arranged in a triangular pattern creating a plane. In the 6 experimental groups, the center implant was perpendicular to the plane of the cast while the outer implants had 5, 10, or 15 degrees convergence towards or divergence away from the center implant. The control definitive cast had all 3 implants parallel to each another and perpendicular to the plane of the cast. Five open tray and 5 closed tray addition silicone impressions were made of each definitive cast. Impressions were poured with type IV dental stone, and a fine tip measuring stylus was used to record multiple axis (X-Y-Z) coordinates on the top surface of the implant hex and on the cast base. Computer software was used to align the data sets and vector calculations determined the difference in degrees between the implant angles in the definitive cast and the duplicate casts. Statistical analysis used repeated-measures ANOVA (alpha=.05) with post-hoc tests of significant interactions. RESULTS: The angle errors for the closed and open tray impression techniques did not differ significantly (P=.22). Implant angulations and implant numbers differed in average angle errors but not in any easily interpreted pattern (P<.001). The combined interaction of impression technique, implant angulation, and implant number had no effect on the accuracy of the duplicate casts compared to the definitive casts (P=.19). CONCLUSIONS: The average angle errors for the closed and open tray impression techniques did not differ significantly. There was no interpretable pattern of average angle errors in terms of implant angulation and implant number. The magnitude of distortion was similar for all combinations of impression technique, implant angulation, and implant number.     

Bone level changes at axial- and non-axial-positioned implants supporting fixed partial dentures. A 5-year retrospective longitudinal study

AIM: The aim of this study was to retrospectively analyze the potential influence of implant inclination on marginal bone loss at freestanding, implant-supported, fixed partial dentures (FPDs) over a 5-year period of functional loading. MATERIAL AND METHODS: The material comprised 38 periodontally treated, partially dentate patients with a total of 42 free-standing FPDs supported by implants of the Astra Tech System. Mesio-distal inclination of the implants in relation to a vertical axis perpendicular to the occlusal plane was measured with a protractor on standardized photographs of the master cast. The two tail quartiles of the distribution of the implants with regard to the implant inclination were defined as axial-positioned (mean 2.4 degrees; range 0-4 degrees) and non-axial-positioned implants (mean 17.1 degrees; range 11-30 degrees), respectively. For FPDs supported by two implants, both the mesial-distal and buccal-lingual inter-implant inclination was measured. The primary outcome variable was change in peri-implant bone level from the time of FPD placement to the 5-year follow-up examination. Comparison between axial- and non-axial-positioned implants was performed by the use of a Mann-Whitney U-test. Spearman's correlation analysis was used to analyze relationships between inter-implant inclination (mesial-distal and buccal-lingual) and 5-year bone level change on the FPD level. RESULTS: The 5-year mean bone level change amounted to 0.4 mm (SD 0.97) for the axial and 0.5 mm (0.95) for non-axial-positioned implants (P>0.05). For the FPDs supported by two implants, the mean inter-implant inclination was 9.2 degrees (1-36 degrees) in the mesial-distal direction and 6.7 degrees (0-24 degrees) in the buccal-lingual direction. Correlation analysis revealed lack of statistically significant correlation between inter-implant inclination (mesial-distal and buccal-lingual) and 5-year bone level change (r=-0.19 and r=-0.32, respectively). CONCLUSION: The study failed to support the hypothesis that implant inclination has an effect on peri-implant bone loss.     

The zygomaticus implant protocol in the treatment of the severely resorbed maxilla.

The zygomaticus dental implant, designed by NobelBiocare, was developed primarily for the treatment of the severely resorbed maxilla. Br?nemark has reported an overall success rate of 97.6% with the placement of over 200 zygomatic implants during the period 1989 to 2001. There are well-defined characteristics within the patient's resorbed skeletal frame which guide the surgical placement of the zygomatic implant, thus determining whether the surgeon should use an implant with a 45 degrees or 55 degrees angulated head. This allows implant-supported restoration of the resorbed maxilla with a fixed cross arch prosthesis in the maxilla without a bone graft to the posterior maxilla. The use of a modified head angulation of 55 degrees, with implant placement as close to the crest of the edentulous ridge as possible, allows restorative clinicians to achieve an ideal restorative position in the posterior maxilla. The use of a zygomatic implant with a 55 degrees head reduces the buccal cantilever by 20%.     

Fabrication and use of a simple implant placement guide

Proper placement and orientation of dental implants is a requirement for optimum function and esthetics to be obtained with the definitive restoration. This article describes an acrylic resin implant placement guide which is simple to fabricate and easy to use. This device guides the surgeon in the precise position and angulation planned for the implant, yet allows for some flexibility in the event slight adjustments are necessary during surgery.     

Evaluation of the effect of the residual bone angulation on implant-supported fixed prostheses in mandibular posterior edentulism. Part I: Spiral computed tomography study

Dental implants are usually angulated buccolingually because of the anatomy of the residual bone in mandibular posterior edentulous cases. Although angulated dental implants compromise the construction of implant-supported prostheses, the effect of buccolingual angulation of the residual bone has not been clearly stated. This study is performed to determine the biomechanical effect of buccolingual angulation. The goal was to reveal the actual buccolingual angulation values of the residual bone in which implants were to be placed. Thirty mandibular Kennedy I and II cases comprised of forty edentulous posterior regions with missing second premolars and first, second, and third molars were included. Buccolingual angulation values along the 28 mm of residual bone were measured on 1-mm spacing cross-sectional images of spiral computed tomography. Paired sample t test was used for the statistical analysis. The minimum angulation values at the second premolar, first molar, and second molar region were 0 degrees, 3 degrees, and 9 degrees, respectively. The average angulation values were 4 degrees, 10 degrees, and 15 degrees, respectively, and the maximum angulation values were 11 degrees, 18 degrees, and 22 degrees, respectively. The ability to measure the buccolingual angulation of mandibular posterior residual bone before dental implantation may help the clinician at the implant treatment-planning phase.