Crestal Width Research Articles

Conventional Versus Osseodensification Drilling in the Narrow Alveolar Ridge: A Prospective Randomized Controlled Trial.

Background Conventionally, undersized osteotomies were used to increase initial bone-to-implant contact to achieve primary stability in implantology. This is particularly evident in regions with low bone density. The potential for severe bone compression and ischemia poses a challenge to secondary stability. Instead, lateral bone compaction is caused by the idea of osseodensification. Research on the potential benefits of this method for narrow ridges is lacking. This study aimed to determine if the osseodensification drilling technique affects primary stability and how much the alveolar ridge expands following implant site preparation. Methodology A total of 30 participants aged 20 to 80 years were included in this randomized controlled clinical investigation. Each participant was randomly assigned to one of the following two groups: one that received standard drill preparation, and another that received osseodensification drill preparation. Implant stability using implant stability quotient values, crest width, apical width (5 mm from crest), and bone density were assessed both before and after six months using cone-beam computed tomography. Results Osseodensification impacted the width at the apex (5 mm from the crest) and radiographic bone density, adding to the quality, but did not affect implant stability and crestal width after osseointegration. The mean difference in conventional and osseodensification groups was 0.46 and 0.68 mm, respectively, concerning the crestal width. Moreover, the mean difference was 0.74 and 0.58 mm for conventional and osseodensification groups, respectively, concerning the width at the apex (5 mm from the crest). Conclusions This study demonstratesthat the osseodensification process increased both the radiographic bone density and the width at the apex, demonstrating that osseodensification drilling techniques allow for the placement of implants with larger diameters innarrow alveolar ridges.

Immediate Implant and Customized Healing Abutment for a Periodontally Compromised Socket: 1-Year Follow-Up Retrospective Evaluation.

Immediate dental implant placement with or without immediate loading is reported in daily dentistry and implantology, but these procedures are not common in the case of periradicular and periapical lesions around the tooth needed to be replaced. In the following retrospective evaluation, 10 cases with a 1-year follow-up were selected to propose the technique of an immediate provisional non-loading prosthesis being delivered on the same day of the post-extraction implant placement in multiradicular teeth affected by chronic periradicular and periapical lesions. Post-extractive sockets underwent immediate dental implant placement by filling the empty space with sterile, re-absorbable gelatin sponges. The widths of the alveolar ridge were measured on three-dimensional radiographs before and after the operation, 4 and 12 months later. Non-parametric statistics were performed to compare the outcomes over time with a level of significance of 0.05. Comparing the preoperative cross-sectional images of cone beam computerized tomography (CBCT) scans to the postoperative ones, it was noted that changes in the crestal ridge width, ΔCW, (compared to baseline) were negligible and not clinically appreciable. However, while ΔCW at 4 months appeared to be negative (-0.17 ± 045 mm), crestal width at 12 months was at the same level as the baseline (ΔCW = 0.02 ± 0.48 mm), with a significant difference between 4 and 12 months (p-value = 0.0494). Immediate implant placement with an immediate non-loading provisional customized healing abutment of polyether-ether-ketone placed into the post-extractive sockets with asymptomatic and large chronic periapical and periradicular lesions could represent a further treatment strategy for patients' rehabilitation and soft tissue preservation to replace a hopeless tooth.

Frozen Stored Teeth: Autogenous Dentin as an Alternative Augmentation Material in Dentistry.

Tooth Shell Technique (TST) with the use of autologous dentin has proven to be a suitable method of grafting in the context of lateral ridge augmentation. This present feasibility study aimed to retrospectively evaluate the preservation by lyophilization of processed dentin. Thus, the frozen stored processed dentin matrix (FST: 19 patients with 26 implants) was re-examined with that of processed teeth used immediately after extraction (IUT: 23 patients with 32 implants). Parameters of biological complications, horizontal hard tissue loss, osseointegration, and buccal lamella integrity were used for evaluation. For complications, the observation period was 5 months. Only one graft was lost (IUT group). In the area of minor complications, without the loss of an implant or augmentation, there were two cases of wound dehiscence and one case with inflammation and suppuration (IUT: n = 3, FST: n = 0). Osseointegration and integrity of the buccal lamella were present in all implants without exception. Statistically, there was no difference between the groups studied for the mean resorption of the crestal width and the buccal lamella. Results of this study show that prepared autologous dentin preserved with a conventional freezer had no disadvantage compared to immediately use autologous dentin in terms of complications and graft resorption in the context of TST.

Periosteum as a covering vascular flap in posterior mandibular augmentation: A retrospective cohort study

ObjectiveTo analyze the impact of creating periosteal vascular flaps on the amount of bone augmentation following inlay bone grafting (IBG) and cortical autogenous tenting (CAT). Materials and MethodsThis was a retrospective cohort study enrolling a sample cohort of patients presented to a private clinic in 2015 and 2019 for posterior mandibular ridge augmentation before dental implant placement. The predictor variables were surgical methods: CAT vs. CAT in conjunction with periosteal flap (CATP) vs. IBG vs. IBG in conjunction with periosteal flap (IBGP). The primary outcome variables were supra bundle bone (SBB) superior to the inferior alveolar canal (ΔH) and crestal width difference (ΔW) at a 4-month follow-up. Appropriate statistics were computed at 0.05 significance level. ResultsA total of 29 cases (10 males and 19 females) with a mean age of 57.96±7.14 years were included. A total of 33 sites were augmented through CATP, 16 sites through IBGP, 33 sites through CAT, and 11 sites through IBG techniques. All patients healed uneventfully without permanent neurosensory changes, and adequate horizontal (ΔW:3.33±0.71 mm) and vertical (ΔH:5.10±2.04 mm) bone dimensions were restored that allowed implant placement. Using periosteal vascular flaps significantly increased bone augmentation in both vertical and horizontal dimensions (P < 0.01). ConclusionPeriosteal vascular flaps can increase the efficacy of mandibular augmentation techniques and decrease post-surgical complications.

Decoronation-induced infected alveolar socket defect rat model for ridge preservation

Current rat alveolar ridge preservation models have not been well standardized. In this study, we proposed decoronation-induced infected alveolar socket model of rat. The bilateral maxillary first molars (M1) of twenty-four rats were decoronized or extracted. After 2, 6, 10, and 14 weeks, bone and soft tissue changes at M1 and periodontal conditions of maxillary second (M2) and third molars (M3) were evaluated by micro-computed tomography and histological analysis. Additional eighteen rats with standardized size defects were grafted with Bio-Oss Collagen to compare with unmanipulated contralateral side. Decoronation preserved greater bone and soft tissue dimensions at M1, provided larger three-dimensional (3D) bone contour volume, but also promoted periodontal breakdown of M2 Histological results showed intense inflammatory cell infiltrations and severe bone resorption within M1 socket and at mesial aspect of M2. The critical dimensions to accommodate largest standardized defect at M1 were 2.2–2.3 mm at vertical bone height and 2.8–3.2 mm at alveolar crestal width. Bio-Oss Collagen could not fully preserve buccal or palatal bone height but could be beneficial in preserving ridge width in large alveolar defects. Collectively, if periodontally-involved alveolar bone defect is preferred, we suggest extracting M1 roots 6 weeks after decoronation to allow periodontitis to occur at M2. If standardized critical dimension defect is preferred, we suggest extracting M1 roots 2 weeks after decoronation, and creating defect in the middle of M1 site with size no larger than 2.7 mm diameter to its full depth.

Lateral Alveolar Ridge Augmentation with Autologous Dentin of Periodontally Compromised Teeth: A Retrospective Study.

Tooth shell technique (TST) using autologous dentine is possible with lateral ridge augmentation while avoiding a donor region. This study aimed to clarify whether the use of periodontally compromised teeth (PCT) leads to similar results compared to non-periodontally compromised teeth (NPCT). In this retrospective study, the dentin matrix of 41 patients (PCT: n = 19 with 29 implants; NPCT: n = 22, with 29 implants) was used for TST. All cases were re-examined. Outcome parameters were biological complications, horizontal hard tissue loss, osseointegration, and the integrity of the buccal lamella. Only in one case in the PCT group, a graft was lost. In three cases, minor complications were identified, including two cases of wound dehiscence and one case of inflammation with suppuration (PCT: n = 1, NPCT: n = 3). All implants, except the one with the severe complication, were osseointegrated and the integrity of the buccal bone lamella was preserved. Mean difference of the resorption of the crestal width and the buccal lamella did not differ statistically between the two groups. TST using PCT showed results comparable to those of NPCT in terms of complications and graft resorption. Processed dentin matrix from PCT can be used and applied with predictable results for bone grafting, utilizing TST.

Marginal Bone Level and Bone Quality Evaluation Using CBCT after Functional Loading around Dental Implant in the Population of Bhubaneswar, Odisha: A Longitudinal Study

Introduction: The importance of Cone Beam Computed Tomography (CBCT) in the field of Implant Planning is a rapidly emerging imaging modality for the purpose of implant planning. Having the obvious benefits over the conventional methods of radiography, CBCT by far is the most promising aid in the efficient implant-supported prosthetic field.&#x0D; Aim: The present study aimed to evaluate the bone density and the height and width around dental implants and compare it to that of the edentulous space before placing the implant.&#x0D; Materials and Methods: A longitudinal study was conducted in the Department of Oral Medicine and Radiology of Kalinga Institute of Dental Sciences, Bhubaneswar. A total of 20 subjects from the CBCT database of the department with a single posterior edentulous space indicated for implant-supported dental prosthesis were selected. Approval of the Ethical Committee was taken. A pre-implant radiographic assessment was done with the help of CBCT, to evaluate the crestal height, crestal width and bone density, followed by surgical placement of the implant. After 6 months of implant placement, a post-operative radiographic assessment was done to evaluate the same parameters. &#x0D; Results: The mean difference of pre- and post-implant crestal width was 0.57 (p&lt;0.001), crestal height was 0.5 (p&lt;0.001) and bone density was 58.2 (p&lt;0.001). It was observed that the mean crestal height, width and bone density was higher in the post-operative radiographic assessment compared to the pre-operative radiographic assessment and the difference was statistically significant.&#x0D; Conclusion: From the given results, it can be concluded that alveolar bone width, height and bone density were significantly improved after implant placement and the osseointegration occurring after implant prosthesis greatly improves the periodontal status of the peri-implant tissues.

Comparative Efficacy of Osteotome vs CAS Kit Assisted Indirect Maxillary Sinus Lift and Immediate Implant Placement in Posterior Atrophic Maxilla – A Study Protocol

Background: In today’s era implants are mostly used for replacing missing teeth. The greatest challenge for placing an implant is posterior maxillary teeth where the problems arise due to presence of maxillary sinus due which increases the risk of perforating the sinus membrane while implanting. In literature there are many techniques to overcome these problems and place the implant without perforating the sinus membrane. The current study is conducted to check either the traditional technique osteotome or modern technique CAS-Kit is better for placing an implant in posterior maxillary region.&#x0D; Objectives: The aim of these study is to compare and evaluate clinical and radiological outcomes of conventional osteotome technique and CAS kit use for indirect sinus lifting in atrophic posterior maxilla.&#x0D; Methodology: Two groups (study &amp; control) with 20 individuals requiring implant prosthesis in atrophic posterior maxillary region with RBH &lt; 3mm and minimum crestal width of 6mm are considered for the study model. After completion of osteotome and sinus lift procedure, integrity of sinus membrane will be checked by Valsalva manoeuvre. At three months after implant placement a second step surgery will be performed, stability of each implant will be checked. Marginal bone loss and amount of bone generation will be checked on Cone-beam computed tomography systems (CBCT) at 3, 6 &amp; 9 month interval.&#x0D; Expected Results: CAS kit is relatively newer and advanced equipment which is safer in placing implant in posterior atrophic maxilla without perforating sinus membrane with good amount of bone generation and stability of implant. with minimal marginal bone loss.&#x0D; Conclusion: Placement of an implant with CAS-Kit is better option than performing osteotome procedure which is time consumable with high chance of membrane perforation and large amount of marginal bone loss.

Guided Bone Regeneration with Concentrated Growth Factor Enriched Bone Graft Matrix (Sticky Bone) vs. Bone-Shell Technique in Horizontal Ridge Augmentation: A Retrospective Study.

Background: The purpose of this study was to compare clinical results of two different horizontal ridge augmentation techniques: guided bone regeneration with sticky bone (SB) and the bone-shell technique (BS). Methods: Records of patients who underwent horizontal ridge augmentation with SB (test) and BS (control) were screened for inclusion. Pre-operative and 6-month post-operative ridge widths were measured on cone beam computer tomography (CBCT) and compared. Post-operative complications and implant survival rate were recorded. Results: Eighty consecutive patients were included in the present study. Post-operative complications (flap dehiscence, and graft infection) occurred in ten patients, who dropped out from the study (12.5% complication rate). Stepwise multivariate logistic regression analysis showed a significant inverse correlation between the occurrence of post-operative complications and ridge width (p = 0.025). Seventy patients (35 test; 35 control) with a total of 127 implants were included in the final analysis. Mean ridge width gain was 3.7 ± 1.2 mm in the test and 3.7 ± 1.1 mm in the control group, with no significant difference between the two groups. No implant failure was recorded, with a mean follow-up of 42.7 ± 16.0 months after functional loading. Conclusions: SB and BS showed comparable clinical outcomes in horizontal ridge augmentation, resulting in sufficient crestal width increase to allow implant placement in an adequate bone envelope.

Retrospective Study on Tooth Shell Technique Using Endodontically Treated Teeth in Lateral Ridge Augmentation

Autogenous dentin has been reported to be a suitable grafting material for certain indications. The purpose of this study was to assess the feasibility of using endodontically treated teeth for this application. In the present retrospective study, one-stage augmentation of lateral ridge defects with a dentin shell and particulate (tooth shell technique (TST)) either obtained from endodontically treated teeth (ETT, 17 patients with 21 implants) or non-endodontically treated teeth (NETT, 17 patients with 24 implants) were analyzed. Follow-up was conducted 3 months after augmentation. The target parameters were biological complications, horizontal hard tissue loss, osseointegration, and the integrity of the buccal lamella. Only minor complications occurred in three implants from three patients, including two cases of wound dehiscence (one each in ETT and NETT) and a localized three-walled defect in the NETT group, which was solved by re-augmentation. All the implants were osseointegrated and the integrity of the buccal lamella was preserved. The mean difference of the resorption of the crestal width and the buccal lamella did not differ statistically between the two groups. As TST using ETT showed, the results comparable to those of NETT dentin from endodontically treated teeth can be safely applied with predictable results for this grafting technique.

Impact of bone defect morphology on the outcome of reconstructive treatment of peri-implantitis

ObjectivesTo assess if (I) the alveolar bone defect configuration at dental implants diagnosed with peri-implantitis is related to clinical parameters at the time of surgical intervention and if (II) the outcome of surgical intervention of peri-implantitis is dependent on defect configuration at the time of treatment.Materials and methodsIn a prospective study, 45 individuals and 74 dental implants with ≥ 2 bone wall defects were treated with either an autogenous bone transplant or an exogenous bone augmentation material. Defect fill was assessed at 1 year.ResultsAt baseline, no significant study group differences were identified. Most study implants (70.7%, n = 53) had been placed in the maxilla. Few implants were placed in molar regions. The mesial and distal crestal width at surgery was greater at 4-wall defects than at 2-wall defects (p = 0.001). Probing depths were also greater at 4-wall defects than at 2-wall defects (p = 0.01). Defect fill was correlated to initial defect depth (p < 0.001). Defect fill at 4-wall defects was significant (p < 0.05).Conclusions(I) The buccal-lingual width of the alveolar bone crest was explanatory to defect configuration, (II) 4-wall defects demonstrated more defect fill, and (III) deeper defects resulted in more defect fill.

Implant placement in conjunction with ridge split and expansion technique

AbstractAimThe aim of this study was to evaluate the efficacy of ridge split technique and expansion technique to analyse peri‐implant hard tissue changes following implant placement.Materials and methodsA prospective study was conducted at Swami Devi Dyal Hospital &amp;Dental College, Panchkula, India, from 2015‐2017 on 10 patients, having at least 1–3 teeth missing, with a crestal width of at least 3 mm and an 8 mm apico‐coronal height (3 × 8 mm) from major anatomical structures.ResultsOut of the 10 patients in whom the inclusion criteria met, six were male and four were female. Out of a total of 20 implants inserted, (13 implants in mandible and 7 in maxilla), healing was uneventful in all cases with no major complication. The mean bone width bucco‐lingually preoperatively was found to be 3.79 ± 0.36 mm and bucco‐lingual width recorded immediately after RST was found to be and 6.38 ± 0.51 mm. This difference in bone width was found to be significant (P = 0.000). Also, a significant correlation was seen (P = 0.003), further strengthening the results obtained.ConclusionsWithin the limits of our study, placing implants with simultaneous ridge splitting can reduce the period of edentulism and reduces the duration of treatment with excellent results. Though it is an operator‐dependant technique and it cannot increase the vertical height of the ridge, still ridge split and expansion technique is the best method for augmentation and simultaneous implant insertion in case of narrow ridges with minimum morbidity and less treatment duration.

Ridge preservation procedures revisited: A randomized controlled trial to evaluate dimensional changes with two different surgical protocols.

The effect of different surgical techniques for ridge preservation on soft tissue parameters has seldom been investigated. The objective of this study was to compare the effect of two different ridge preservation techniques on soft and hard tissue dimensions. Thirty patients requiring tooth extraction were randomly allocated to either control group C (allograft covered with a non-crosslinked collagen membrane with primary closure) or experimental group E (allograft covered with cross-linked collagen membrane left exposed). Sites were surgically re-entered at 6 months. Soft and hard tissue measurements, cone beam computed tomography (CBCT), and cast measurements were taken at baseline and 6 months. Twenty-eight patients were included in this analysis. When the two treatment groups were compared, the width of the buccal keratinized tissue in the E group showed an increase of 0.43±0.42 mm compared to net loss of 1.57±0.51 mm for the C (P=0.006). Similarly, buccal tissue thickness has increased in the E group 0.46±0.22 mm compared to a loss of 0.15±0.23 mm in the C group (P=0.068). Volumetric assessment of the changes in the alveolar ridge for the E group showed a slight decrease (68.3±17mm3) whereas the C group has experienced almost double this loss (107.5±11mm3; P=0.07). Crestal width, measured on the CBCT scan, has shown significant reduction in the C group (4.18±0.56 mm) compared to only 1.74±0.4 mm in the E group (P=0.003). Crosslinked collagen membrane with allograft placed intentionally non-submerged resulted in better preservation of the keratinized tissues (width and thickness) with similar and at times better osseous preservation following extraction.

Effects of artifact removal on cone-beam computed tomography images

Dental implants and metal fillings may cause artifacts in cone-beam computed tomography (CBCT) images and reduce image quality and anatomic accuracy. The purposes of this study are a subjective evaluation of anatomic landmarks and linear bone measurements after applying artifact removal (low-medium) option on CBCT images. In this cross-sectional study, thirty CBCT images from thirty qualified patients were selected in a private radiology center. Low and medium artifact removal was applied to images. Three radiologists assessed the visibility of the mandibular canal, mental foramen, and lamina dura in images. Crestal width and bone length were also measured in three groups of images and was compared by exact McNemar test. ICC test (two-way random model, absolute agreement types) was calculated for comparison of linear bone measurements in three images groups. P ≤ 0.05 was considered statistically significant. Percent agreement of determining mental foramen (outline and location), mandibular canal (outline and location), and lamina dura between three groups of images were 100%, 100%, 83.3%, 96.7%, and 56.6%, respectively. The results of exact McNemar test revealed that medium artifact removal group had a statistical difference in lamina dura observation with none and low artifact removal groups (P < 0.001). Intraclass correlation coefficient showed no statistical differences in crestal width and bone length between groups (P < 0.001). Applying artifact removal does not affect the visibility of large anatomical structures and linear bone measurements, but delicate structures such as lamina dura may become less clear after artifact removal.

Safety and performance of a novel collagenated xenogeneic bone block for lateral alveolar crest augmentation for staged implant placement

To evaluate the performance and safety of placing a collagenated xenogeneic bone block (CXBB) graft for the lateral bone augmentation of the alveolar crest prior to implant placement. In patients with single or multiple tooth gaps and a severe horizontal collapse of the alveolar ridge, a ridge augmentation procedure was performed using CXBB fixated with osteosynthesis screws to the atrophic bone crest and complemented with deproteinized bovine bone mineral particles (DBBM) and a native bilayer collagen membrane (NBCM). Patients were examined with CBCT prior to and 24weeks after the augmentation. Twenty-six weeks postoperatively, a re-entry procedure was performed to evaluate the bone width and availability for adequate implant placement. Fifteen patients received 28 CXBB, and in 13 patients, a re-entry procedure was performed. Eleven patients (84.6%) gained enough bone volume for implant insertion without additional contouring or secondary bone augmentation. The mean crest width at baseline was 2.83mm (SD 0.57), and the mean crest width at re-entry was 6.90mm (SD 1.22), with a mean ridge width increase of 4.12mm (SD 1.32). Soft tissue dehiscence occurred during the follow-up in 5 of 14 patients (35.7%) at various time points. In addition, there was a high incidence of early implant loss (30.8% [patient-based]). CXBB achieved significant horizontal crestal width gains allowing a secondary implant placement in the majority of the patients. However, the occurrence of soft tissue dehiscence may notably affect the outcome of the subsequent implant therapy.

Histomorphometric and immunohistochemical evaluation of collagen containing xenogeneic bone blocks used for lateral bone augmentation in staged implant placement

BackgroundThe osteoconductive properties of collagen containing xenogeneic bone blocks (CCXBB) remain unclear. The aim of this prospective single-arm clinical study was to assess the histological outcomes of CCXBB blocks used as bone replacement grafts for lateral bone augmentation procedures.MethodsIn 15 patients with severe horizontal alveolar ridge resorption, lateral augmentation procedures were performed using CCXBB as bone replacement grafts. Twenty-six weeks postoperatively, a re-entry procedure was performed to evaluate the bone width for adequate implant placement and two histological specimens were retrieved from each patient, one being processed for ground sectioning and the other for decalcified paraffin-included sections. In non-decalcified sections, the relative proportions occupied by bone, biomaterials, and connective tissue present in the biopsies were identified. In de-calcified sections, structures and cells positive for osteopontin (OPN), tartrate-resistant acid phosphatase activity (TRAP), osteocalcin (OSC), and alkaline phosphatase (ALP) were assessed.ResultsSoft tissue dehiscence occurred during the follow-up in 5 out of 15 patients (33.3%). The mean crest width at baseline was 2.78 mm (SD 0.57) and the mean crest width at re-entry was 6.90 mm (SD 1.22), with a mean ridge width increase of 4.12 mm (SD 1.32). Twenty-six bone biopsies were obtained from 13 patients. Histomorphometric analysis showed a mean of 26.90% (SD 12.21) of mineralized vital bone (MVB), 21.37% (SD 7.36) of residual CCXBB, 47.13% (SD 19.15) of non-mineralized tissue, and 0.92% of DBBM. The immunohistochemical analysis revealed a large number of OPN-positive cells 8.12% (SD 4.73), a lower proportion of TRAP positive multinuclear cells 5.09% (SD 4.91), OSC-positive cells 4.09% (SD 4.34), and a limited amount of ALP positive cells 1.63% (SD 2).ConclusionsCCXBB achieved significant horizontal crestal width allowing for staged implant placement in most of the patients. In light of the histological outcomes and implant failures, special attention must be placed to prevent soft tissue dehiscence when CCXBB is used in severe atrophic alveolar crests.

Effect of Alveolar Segmental Sandwich Osteotomy on Alveolar Height: A Preliminary Study.

Bone loss following extraction is maximum in horizontal dimension. Height is also reduced which is pronounced on the buccal aspect. Various surgical procedures are available to correct the bone volume viz. GBR, onlay bone grafting, alveolar distraction and sandwich osteotomy. Sandwich osteotomy has been found to increase the vertical alveolar bone height successfully. The objective of the study was to assess the effect of alveolar segmental sandwich osteotomy on alveolar height and crestal width. A prospective study was undertaken from December 2012 to August 2014. Seven patients with 12 implant sites with a mean age of 36years were recruited. All seven patients with 12 implant sites underwent alveolar segmental sandwich osteotomy and interpositional bone grafting. Alveolar bone height was assessed radiographically preoperatively, immediate post-op, and at 3months post-op. Alveolar bone width was assessed radiographically preoperatively and at 3months post-op. Statistical significance was inferred at p<0.05. The mean vertical augmentation at immediate post-op was 6.58mm (p=0.001). The vertical augmentation that was achieved 3months post-op was a mean of 3.75mm which was statistically significant (p=0.004). The change in alveolar height from immediate post-op to 3month post-op was a mean 1.69mm. The mean change in alveolar crestal width at 3months was a mean of -0.29mm (p=0.57). Sandwich osteotomy can be used as an alternative technique to increase alveolar bone height prior to implant placement. Moderate alveolar deficiency can be predictably corrected by this technique.

Alveolar ridge dimensional changes following ridge preservation procedure using SocketKAP(™) : exploratory study of serial cone-beam computed tomography and histologic analysis in canine model.

The aim of this pilot study was to examine the kinetics of alterations in alveolar ridge width and height following tooth extraction with and without ridge preservation, using anorganic bovine bone mineral (ABBM) and a novel device (SocketKAP(™) ) designed for obturation of socket orifice. Maxillary left and right PM1 and mandibular right PM2 and PM4 were extracted on six beagle dogs and treated as follows: Group A: negative control; Group B: SocketKAP(™) alone; Group C: ABBM+SocketKAP(™) . Serial cone-beam computed tomography (CBCT) was taken at 0-, 1-, 2-, 4-, 8- and 12-week intervals to calculate the rate of alveolar bone loss, followed by histologic and histomorphometric analyses at 12weeks. Across group outcomes were compared. Without additional intervention, the crestal-most 3mm of alveolar bone width lost approximately 0.21-0.28mm per week. The rate of alveolar buccal bone height loss was 0.19mm per week. Comparatively, in group C, the alveolar bone was relatively stable, with loss of only 0.003-0.13mm of width and 0.12mm of height per week. These differences were statistically significant. The alveolar bone in sites treated by SocketKAP(™) alone was significantly different from control only at select time points and locations of the ridge, presumably due to small sample size. Without additional intervention, tooth extraction was accompanied by rapid loss of alveolar ridge width and height. Applications of SocketKAP(™) and ABBM were effective in reducing alveolar crestal width and height loss following tooth extraction.

Assessment of Bone Width for Implants in the Posterior Mandible

After implants are placed into mandibular molar sites, it is assumed that crestal bone width will not change considerably over time. The purpose of this retrospective study was to determine crestal bone changes for implants placed into mandibular molar locations. The hypotheses for all groups (immediate, delayed, and grafted) were that no major changes in bone width of the posterior mandible would occur in the long term. This is a retrospective cohort study involving 3 groups of patients within the senior author's practice who had at least 4 years of follow-up cone-beam computed tomograms available for measurement. The primary outcome variable, crestal width, was measured at 3 intervals, namely at tooth removal, before implant placement, and 4 to 5 years after placement. Group A underwent tooth extraction with immediate implant placement; group B underwent tooth extraction with delayed implant placement; and group C underwent tooth extraction with socket grafting and implant placement 4 months after grafting. Standardized cross-sectional cone-beam computed tomograms were used to measure ridge width. Two-sample t tests and regression analysis were used to compare crestal width measurements at different periods among groups. Analysis of variance was adapted to check whether ridge widths among groups were confounded by variables, such as age, gender, and medical comorbidities. Age, gender, medical comorbidities, and smoking were not statistically related to the outcome. Long-term comparisons indicated small yet significant (P = .0124) differences at the crestal level. The greatest change was for the grafted group, with width change from 12.4 ± 2.1 mm before extraction to 9.9 ± 1.8 mm 4 to 5 years after implant placement. Bone width changes 5 and 10 mm inferior to the crest did not change over time. Within the time course and sample size evaluated, the thickness of the buccal bone seems to be maintained over time, regardless of method used, with small yet important changes from before tooth removal through the long-term.

Delayed expansion of the atrophic mandible by ultrasonic surgery: a clinical and histologic case series.

Ridge expansion is used to widen narrow ridges with adequate height for implant placement. This human case series presents the clinical and histologic results of delayed expansion of mandibles by ultrasonic surgery. Patients with residual alveolar ridge width between 2.3 and 4.1 mm in the coronal area of the posterior mandible were included in the study. First, four linear corticotomies were carried out by ultrasonic surgical device. Four weeks later, adequate bone expansion with a combination of scalpels, thin chisels, and threaded osteotomes that did not compromise cortical vascularization was performed, and two implants per ridge were inserted. Any gaps were filled with corticospongious porcine biomaterial. Three months after implant placement, healing caps were inserted, and bone cores were harvested from the regenerated areas for histologic analysis. Crestal width was recorded at each surgery. The postoperative course was uneventful in all 32 patients (64 implants) who took part in the study, and the implant success rate was 96.88% at 3 months. The mean increase in ridge width was 5.17 ± 0.86 mm. The histologic specimens showed a mixture of new bone and particles of biomaterial, as well as newly formed bone. Histomorphometry demonstrated that 64% ± 3.1% of the specimen was composed of newly formed bone, 8% ± 0.8% was made up of marrow spaces, and 27% ± 2.6% comprised the residual grafted biomaterial. This study showed that mandibular ridge expansion using a delayed split-crest technique by means of ultrasonic surgery and association with biomaterial led to good horizontal bone gain, with no fractures of the buccal plate, and a high implant success rate. The histologic specimens showed newly formed bone and good integration of the biomaterial.