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Background Little attention has been paid to the effect of implant restorations on speech. Purpose The aim of this study was threefold: (1) to find out if speech problems occur after inserting a fixed provisional restoration in the edentulous maxilla; (2) to explore speech adaptation in case articulation problems arise after rehabilitation; and (3) to describe the effect of changing the shape of the restoration on improving speech. Materials and Methods Ten patients with an edentulous maxilla were treated with fixed rehabilitation on implants. Speech evaluation was performed at four occasions: before implant surgery, immediately after restoration, and 3 weeks later before and after managing the speech problem by changing the shape of the restoration if speech problems occurred. Comparative three-dimensional-analysis of casts of the restoration before and after changing the shape of the restoration was carried out. Results The majority of patients (n = 7) experienced speech problems immediately after rehabilitation. Three weeks later, none of the seven patients with deteriorated speech returned to baseline speech. Then, volumetric reduction of the palatal aspects of the (pre)molars was performed, which allowed speech to return to baseline levels in five out of seven patients. In the two remaining patients, the intervention resulted in an improvement of speech without reaching their baseline levels. Three-dimensional-analysis showed that reducing the palatal volume of the premolars was effective in correcting speech. Conclusions Speech problems may frequently occur after fixed rehabilitation of the completely edentulous maxilla. A novel speech management concept, consisting of reducing the palatal volume of the (pre)molars, is introduced, demonstrating to solve speech problems in most cases.

Background Information regarding linear accuracy is necessary for efficient treatment evaluation, especially for maxillofacial reconstruction or implants. Purpose To investigate the accuracy of linear measurements from multiple cone beam computed tomography (CBCT) devices. Materials and Methods A RANDO® phantom was scanned with eight CBCT scanners (11 modes). The viewing software accompanying each scanner was employed for measurements in mediolateral, anteroposterior, and supero-inferior dimensions by two dentomaxillofacial radiologists. Digital caliper measurements were used as a “gold standard.” ANOVA with Scheffe post hoc analysis and intraclass correlation coefficient (ICC) were utilized for statistical analyses. The level of confidence was 95%. Results Differences from the gold standard among 11 acquisition modes were statistically significant (p

Background The term bone quality is often used in a dentomaxillofacial context, for example in implant planning, as bone density and bone structure have been linked to primary implant success. Purpose This research aimed to investigate the performance of adaptive thresholding of trabecular bone in cone beam CT (CBCT) images. The segmentation quality was assessed for different imaging devices and upper and lower jaws. Materials and Methods Four jaws were scanned with eight CBCT scanners and one micro-CT device. Images of the jaws were spatially aligned with the micro-CT images. Two volumes of interest for each jaw were manually delineated. Trabecular bone in the volumes of interest in the micro-CT images was segmented so that the micro-CT images could serve as high-resolution ground truth images. The volumes of interest in the CBCT images were segmented using both global and adaptive thresholding. Results Segmentation was significantly better for the lower jaw than for the upper jaw. Differences in performance between the scanners were significant for both jaws. Adaptive thresholding performed significantly better in segmenting the bone structure out of CBCT images. Conclusions When assessing jaw bone structure, the observer should always choose adaptive thresholding. It remains a challenge to identify the optimal threshold selection for the structural assessment of jaw bone.

Purpose To develop a method for characterizing trabecular bone microarchitecture using cone beam computed tomography (CBCT) and to evaluate trabecular bone changes after rehabilitation using immediate versus delayed implant protocols. Materials and Methods Six mongrel dogs randomly received 27 titanium implants in the maxillary incisor or mandibular premolar areas, following one of four protocols: (1) normal extraction socket healing; (2) immediate implant placement and immediate loading; (3) delayed implant placement and delayed loading; (4) delayed implant placement and immediate loading. The animals were euthanized at 8 weeks, and block biopsies were scanned using high resolution CBCT. Standard bone structural variables were assessed in coronal, middle, and apical levels. Results Coronal and middle regions had more compact, more platelike, and thicker trabeculae. Protocols (2), (3), and (4) had significantly higher values (p

Background: The innervation of skin and oral mucosa plays a major physiological role in exteroception. This innervation is also clinically relevant as sensory changes occur after neurosurgical procedures. Purpose: The goal of this study was to compare the perception of mechanical stimuli applied to the buccal mucosa in the vicinity of osseointegrated oral implants with that in the controlateral dentate side. The role of the previously reported increased innervation in the peri-implant soft tissues in the oral sensorimotor function was thus examined. Materials and Methods: Seventeen subjects with 20 implants were tested. Directional cutaneous kinaesthesia (DCK) and graphesthesia (G) were performed on the buccal side of the alveolar mucosa before and at planned intervals after implant placement. The observation was pursued until 6 months after the prosthetic rehabilitation. In each subject, the contralateral mucosa served as a control to the implant sites. Average percentages of correct responses in a four-choice task for DCK and a three-choice task for G were calculated. Results: Despite an intersubject variation in both the DCK and G, high intraindividual correlations were found (p < .005). The implant sites showed a significant difference toward the control sites at the four interval test for both tests. For DCK and G, the average of correct responses decreased after abutment connection (i.e., after the implant uncovering surgery) to increase afterwards to reach a level close to, but still lower than, the control sites 3 to 6 months after the prosthetic rehabilitation. Conclusion: The DCK and G are simple but reliable sensory tests that can be easily applied in the oral region. This prospective study indicates that tooth loss reduces tactile function compared with implant-supported prostheses. The peri-implant soft tissues could be partially involved in the osseoperception function.

Little attention has been paid to the effect of implant restorations on speech.The aim of this study was threefold: (1) to find out if speech problems occur after inserting a fixed provisional restoration in the edentulous maxilla; (2) to explore speech adaptation in case articulation problems arise after rehabilitation; and (3) to describe the effect of changing the shape of the restoration on improving speech.Ten patients with an edentulous maxilla were treated with fixed rehabilitation on implants. Speech evaluation was performed at four occasions: before implant surgery, immediately after restoration, and 3 weeks later before and after managing the speech problem by changing the shape of the restoration if speech problems occurred. Comparative three-dimensional-analysis of casts of the restoration before and after changing the shape of the restoration was carried out.The majority of patients (n = 7) experienced speech problems immediately after rehabilitation. Three weeks later, none of the seven patients with deteriorated speech returned to baseline speech. Then, volumetric reduction of the palatal aspects of the (pre)molars was performed, which allowed speech to return to baseline levels in five out of seven patients. In the two remaining patients, the intervention resulted in an improvement of speech without reaching their baseline levels. Three-dimensional-analysis showed that reducing the palatal volume of the premolars was effective in correcting speech.Speech problems may frequently occur after fixed rehabilitation of the completely edentulous maxilla. A novel speech management concept, consisting of reducing the palatal volume of the (pre)molars, is introduced, demonstrating to solve speech problems in most cases.

Background: The anterior mandible is generally considered a rather safe surgical area, involving few risks of damage to vital anatomic structures. Nevertheless, both neurosensory disturbances and hemorrhages have been reported after implant surgery in that particular area. Purpose: With the increasing demand for oral implant placement, the anatomy of the anterior mandible should receive more attention. This review will focus on the anatomic peculiarities of the anterior mandible and the related clinical implications. Methods: The scientific evidence on the anatomic, histologic, physiologic, and clinical aspects of the neurovascularization of the anterior mandible will be reviewed. Results: Surgical complications may be attributed to the existence of a mandibular incisive canal with a true neurovascular supply. Potential risks may also be related to the presence of the lingual foramen and anatomic variations, such as an anterior looping of the mental nerve. Conclusions: Preoperative radiographic planning for oral implant placement in the anterior mandible should therefore not only consider all esthetic and functional demands but should also pay particular attention to the anatomic peculiarities of this region to avoid any neurovascular complications.

Background: As the use of oral implants for the treatment of partially as well as fully edentulous patients has increased the past two decades, more specialized radiographie techniques have become available for the preoperative planning of oral implant placement. Purpose: The goal of this article was to enable clinicians to select the appropriate imaging techniques when planning for oral implants. Materials and Methods: This article reviews the available literature about various imaging techniques and their indication for the preoperative planning of oral implants. The advantages and drawbacks of each technique are described. A dosimet-ric overview is given relative to different radiologie techniques used in various clinical situations. Results: For preoperative planning of implant placement, advantages and drawbacks of the available imaging techniques have been considered, which allows guidelines for image technique selection to be formulated based on the clinical situation provided, considering the diagnostic yield of each technique and the radiation doses involved. Conclusions: From the available literature, it can be stated that many clinical situations demand the use of cross-sectional imaging techniques for optimal preoperative planning of implant placement. Nevertheless, such techniques are not required in cases in which the clinical examination reveals sufficient bone width and where standard radiographie examinations, such as intraoral and panoramic radiography, reveal adequate bone height and space for implant placement.

Information regarding linear accuracy is necessary for efficient treatment evaluation, especially for maxillofacial reconstruction or implants.To investigate the accuracy of linear measurements from multiple cone beam computed tomography (CBCT) devices.A RANDO® phantom was scanned with eight CBCT scanners (11 modes). The viewing software accompanying each scanner was employed for measurements in mediolateral, anteroposterior, and supero-inferior dimensions by two dentomaxillofacial radiologists. Digital caliper measurements were used as a "gold standard." ANOVA with Scheffé post hoc analysis and intraclass correlation coefficient (ICC) were utilized for statistical analyses. The level of confidence was 95%.Differences from the gold standard among 11 acquisition modes were statistically significant (p .001). Measurements from one unit were always underestimated compared with all others (p .001). The range of absolute measurement errors for tested units was -2.56 to 0.54 mm (mean ± SD 0.45 ± 0.71) including the outlier and -0.34 to 0.54 mm (0.16 ± 0.11) excluding the outlier. Slightly more values were underestimated than overestimated (41 of 66 measurements, 7 out of 11 CBCT modes). ICC scores for inter- and intraobserver agreement were perfect (1.000).Treatment planning from large-volume CBCT was found to be reliable in all except one of the investigated scanners. New CBCT scanners should always be tested for geometric accuracy.

The term bone quality is often used in a dentomaxillofacial context, for example in implant planning, as bone density and bone structure have been linked to primary implant success.This research aimed to investigate the performance of adaptive thresholding of trabecular bone in cone beam CT (CBCT) images. The segmentation quality was assessed for different imaging devices and upper and lower jaws.Four jaws were scanned with eight CBCT scanners and one micro-CT device. Images of the jaws were spatially aligned with the micro-CT images. Two volumes of interest for each jaw were manually delineated. Trabecular bone in the volumes of interest in the micro-CT images was segmented so that the micro-CT images could serve as high-resolution ground truth images. The volumes of interest in the CBCT images were segmented using both global and adaptive thresholding.Segmentation was significantly better for the lower jaw than for the upper jaw. Differences in performance between the scanners were significant for both jaws. Adaptive thresholding performed significantly better in segmenting the bone structure out of CBCT images.When assessing jaw bone structure, the observer should always choose adaptive thresholding. It remains a challenge to identify the optimal threshold selection for the structural assessment of jaw bone.

To develop a method for characterizing trabecular bone microarchitecture using cone beam computed tomography (CBCT) and to evaluate trabecular bone changes after rehabilitation using immediate versus delayed implant protocols.Six mongrel dogs randomly received 27 titanium implants in the maxillary incisor or mandibular premolar areas, following one of four protocols: (1) normal extraction socket healing; (2) immediate implant placement and immediate loading; (3) delayed implant placement and delayed loading; (4) delayed implant placement and immediate loading. The animals were euthanized at 8 weeks, and block biopsies were scanned using high resolution CBCT. Standard bone structural variables were assessed in coronal, middle, and apical levels.Coronal and middle regions had more compact, more platelike, and thicker trabeculae. Protocols (2), (3), and (4) had significantly higher values (p0.001) than protocol (1) for bone surface density, bone surface volume ratio, and connectivity density, while significantly lower values (p0.001) were found for trabecular separation and fractal dimension. However, protocols (2), (3), and (4) did not show significantly different bone remodeling.Compared with normal extraction healing, the implant protocols have an improved bone structural integration. Results do not suggest a different bone remodeling pattern when a delayed versus an immediate implant protocol is used.

The innervation of skin and oral mucosa plays a major physiological role in exteroception. This innervation is also clinically relevant as sensory changes occur after neurosurgical procedures.The goal of this study was to compare the perception of mechanical stimuli applied to the buccal mucosa in the vicinity of osseointegrated oral implants with that in the controlateral dentate side. The role of the previously reported increased innervation in the peri-implant soft tissues in the oral sensorimotor function was thus examined.Seventeen subjects with 20 implants were tested. Directional cutaneous kinaesthesia (DCK) and graphesthesia (G) were performed on the buccal side of the alveolar mucosa before and at planned intervals after implant placement. The observation was pursued until 6 months after the prosthetic rehabilitation. In each subject, the contralateral mucosa served as a control to the implant sites. Average percentages of correct responses in a four-choice task for DCK and a three-choice task for G were calculated.Despite an intersubject variation in both the DCK and G, high intraindividual correlations were found (p.005). The implant sites showed a significant difference toward the control sites at the four interval test for both tests. For DCK and G, the average of correct responses decreased after abutment connection (i.e., after the implant uncovering surgery) to increase afterwards to reach a level close to, but still lower than, the control sites 3 to 6 months after the prosthetic rehabilitation.The DCK and G are simple but reliable sensory tests that can be easily applied in the oral region. This prospective study indicates that tooth loss reduces tactile function compared with implant-supported prostheses. The peri-implant soft tissues could be partially involved in the osseoperception function.

Background: The innervation of skin and oral mucosa plays a major physiologic role in exteroception. It is also of interest clinically, as illustrated by sensory changes after neurosurgical procedures. Purpose: The goal of this study was to assess the perception of mechanical stimuli applied to the anterior maxilla in denture wearers and subjects rehabilitated with osseointegrated implants compared with that in subjects with a natural dentition. Materials and Methods: Five groups of subjects were selected and tested in the maxillary region only. Test groups included patients with a complete denture, an implant-supported fixed prosthesis (full or partial), or a single-tooth replacement. Light-touch sensation and two-point discrimination were performed on the buccal side of the alveolar mucosa and vibrotactile function was determined for natural teeth, full dentures, or implant-supported prostheses. Results: For light-touch sensation, no significant differences could be found between the groups. For two-point discrimination, full-denture patients showed higher threshold levels than the other groups. The threshold levels for vibrotactile function were higher in both full dentures and implant-supported prostheses compared with natural dentitions. Conclusion: Natural dentitions offer superior vibrotactile function compared to any other dental status. Full dentures often show a stronger deterioration of the (vibro)tactile function compared with implant-supported prostheses.

Background: The original protocol or Branemark to achieve predictable osseointegration for oral implants has substantially been modified. One may question whether results are influenced by those modifications, especially for the longterm prognosis. Purpose: The goal of the present study was to investigate the impact of those parameters that deviate from the original protocol as defined by P-I Branemark. Materials and Methods: In this study, 246 patients with 263 fixed partial prostheses supported by 668 Branemark implants were followed from 1 to 15 years (mean:6.3 yr). Radiographs were taken at the time of abutment connection, at 3 to 6 months, at 12 months, and then every 3 years. The bone level was rated mesially and distally from the implants on a total of 2588 radiographs. Results: A positive relation between abutment length and marginal bone level was found (p >.0001). The maxilla (p =.03), porcelain (p =.007), long abutments (p =.008), and regular-sized diameter implants (p =.001) all exhibited more bone loss in the first 6 months. After 6 months, only long implants showed more bone loss (p =.03). Conclusions: Overall, the marginal bone level remained stable around Branemark implants, never surpassing 2.2 mm, even after 15 years. Although longer implants lost more bone over time, this has to be interpreted with respect to higher resorption rates in less resorbed jaws.

Background: The replacement of a single tooth or several teeth by means of single-implant restorations is an increasingly used method that needs long-term validation. Purpose: The goal of this study was to evaluate the outcome of single-implant restorations by means of fixed restorations and to define the prognosis through marginal bone level estimations. Materials and Methods: From November 1986 to June 1998, 270 Branemark implants (215 in the upper jaw) were installed in 219 patients (106 males). Both anterior and posterior sites were involved. Of the 263 single restorations, 28 were placed in private dental offices. The patients were followed until June 1999. Results: Twelve implants failed before or at abutment connection or within 6 months afterward. Only four implants failed later. The cumulative success rates were 93% for the implants and 96.5% for the restorations over a period of 11 years. The marginal bone loss during the first 6 months after abutment connection reached 0.71 mm and then dropped to 0.036 mm annually over a period of 10 years. Conclusions: Single-implant restorations (Branemark System) are a reliable treatment with a good long-term prognosis. Failures were concentrated during the healing period and early loading phase.