One abutment one time vs. repeatable abutment disconnections in implants, restored with cemented / screw retained fixed partial dentures: Marginal bone level changes. A systematic review and meta-analysis

PURPOSE

The aim of this systematic review and meta-analysis is to evaluate the impact of abutment disconnections / reconnections on peri-implant marginal bone loss changes in partially edentulous patients.

METHODS

Clinical studies were selected via electronic and hand searches in English language journals until January 1, 2020. Only randomized clinical trials (RCGTs) and prospective controlled clinical trials (CCTs) showing direct comparison between the definitive implant abutments and multiple abutment replacements in the same patient or different patient groups in the partially edentulous patients were considered. The outcome measures were (1) the type of the abutment was used, (2) the time the abutment was placed, (3) marginal bone loss changes, (4) biological complications, (5) mechanical complications.

RESULTS

After evaluation, 4 controlled clinical studies were included. Majority of the articles reveled protective marginal bone loss preservation for the implants with FAP (final abutment placement) at the time of implant placement compared with the implants with MAP (multiple abutment placements) in connected dental implants, in partially edentulous patients. Meta-analysis of the four studies with 280 implants reviled significantly greater bone loss in cases with multiple abutment disconnections/reconnections. The weighted mean difference in marginal bone loss was 0.4 mm (95% confidence interval, 0.16-0.63 mm), showing bone preservation in the FAP group.

CONCLUSION

Within the limitations of this meta-analysis, multiple abutments disconnections significantly affected marginal bone loss changes in partially edentulous patients. The finding suggests to overview current prosthetic and surgical treatment planning protocols to prevent greater marginal bone loss.

Comparison of Bone Formation After Sinus Membrane Lifting Without Graft or Using Bone Substitute "Histologic and Radiographic Evaluation"

PURPOSE

Sinus floor elevation without using autogenous bone graft or bone substitute will eliminate donor site morbidity and reduce the cost and the risk of infection. We evaluated the bone gain after sinus membrane elevation without graft or using bone substitute in the same maxilla. Dental implants were inserted simultaneously as a 1-stage procedure.

PATIENTS AND METHODS

In a split-mouth design, we conducted a randomized double-blinded clinical trial performing sinus lifts and simultaneous implant insertion in 10 healthy patients (n = 20). On the 1 site, we performed graft-less sinus lift (group 1) and on the other site Cerabone was used as bone substitute (group 2), respectively. The quantity and quality of bone gained in each sinus were evaluated and compared radiologically and histomorphometrically.

RESULTS

After 6 months, the average gain of bone height was 6.21 and 9.58 mm in group 1 and 2, respectively, as measured radiologically (P < .001, P < .001). Histomorphometric examination showed significantly higher thickness of trabeculae and bone formation in group 1 (P = .003 and P = .002). However, the neovascularization was higher, but not significantly (P = .288).

CONCLUSIONS

Radiological bone gain was similar in both groups. However, histomorphometric examination showed superior bone formation in graft-less group as compared to the Cerabone group. The blood clot seems to be an adequate filler and excellent medium for bone formation. More studies in split-mouth design are needed to compare different bone substitutes.

Influence of Bone Anatomy on Implant Placement Procedures in Edentulous Arches of Elderly Individuals: A Cross-Sectional Study on Computed Tomography Images

PURPOSE

To describe the prevalence of alveolar bone atrophy in edentulous arches of elderly individuals in relation to insertion of dental implants and the eventual need for bone grafting procedures.

MATERIALS AND METHODS

Computed tomography scan files of 228 edentulous arches of elderly patients (ages 65 to 100 years) were evaluated in relation to implant placement. Six measurements per arch were taken on cross-sectional reconstructions. Bone atrophy categories were described, in relation to implant placement, for the anterior and posterior sections of the arches. Six bone sections per arch were evaluated and allocated to the predetermined categories. Prevalence of each type of atrophy was calculated.

RESULTS

In the maxilla, only 5.0% of the patients showed a bone anatomy capable of receiving implants without any augmentation both in the posterior and anterior regions; 64.4% showed the need for major reconstruction in both areas. In the mandible, 17.3% of the patients did not require any augmentation in both regions; 9.4% were in need of major reconstruction in both areas. The anterior part of the arches could eventually be treated without any bone augmentation in 10.9% of the maxillae and 72.4% of the mandibles, while minor augmentation was needed in 16.8% of maxillae and 15.8% of mandibles.

CONCLUSION

Most edentulous elderly patients show some degree of alveolar bone atrophy. It is often feasible to insert implants in the anterior mandible to support a restoration. In most maxillary cases, alveolar atrophy calls for augmentation procedures in both the anterior and posterior areas. In elderly individuals, the anterior maxilla often shows bone deficiency interfering with simple implant placement procedures, thus also limiting the use of tilted implants.

Factors Affecting Soft and Hard Tissues Around Two-Piece Transmucosal Implants: A 3-Year Prospective Cohort Study

PURPOSE

This 3-year study aimed to evaluate hard and soft tissue modification around a two-piece implant characterized by a transmucosal hyperbolic neck in healthy consecutive patients with a need for single-tooth replacement.

MATERIALS AND METHODS

Two-piece implants (n = 66) were placed with a flapless technique in 56 patients (27 men; 29 women; mean age 55 ± 9 years): 16 immediately after root extraction (immediate group), 20 after 8 to 12 weeks (early group), and 30 after 10 or more months (delayed group). The transmucosal hyperbolic neck was exposed 1 to 1.5 mm above gingival level. Customized abutments were positioned 3 months later with the implant-abutment connection located approximately 1 to 1.5 mm above soft tissue level. Provisional cemented resin crowns were designed with the finishing line at the hyperbolic neck and then positioned to avoid excessive compression of soft tissue, to guide gingival contours. Twenty days later, a definitive metal-ceramic crown was cemented. In all patients, the gingival biotype (thin or thick) was also evaluated. The primary outcomes were as follows: 36-month implant survival rate, peri-implant marginal bone level (MBL, in mm) changes observed in single-blind on radiographs at 1, 3, 6, 12, 24, and 36 months (T₁, T₃, T₆, T₁₂, T₂₄, and T₃₆), and pink esthetic score (PES) at T₆, T₁₂, and T₃₆ to analyze soft tissue adaptation after loading and crown application. The secondary outcomes were as follows: plaque score and bleeding on probing (BOP). Linear regression models and multilevel mixed logistic regression were used to detect any statistical difference of MBL according to operative parameters. Kruskal-Wallis one-way analysis of variance (ANOVA) on ranks was performed to assess statistical differences of PES at T₆, T₁₂, and T₃₆.

RESULTS

The survival rate was 100%. The dropout rate was 1.79%. No infections, mucositis, or peri-implantitis were reported. Implants placed in thick-biotype tissues showed a statistically different lower bone loss at 36 months with respect to the thin biotype (P < .05). At 36 months, the early group showed lower bone loss compared with the delayed group (P < .05). Multilevel mixed logistic regression revealed that gingival biotype was the parameter that was most related to MBL variations (P = .025). The PES value (mean ± SD) at T₆ was 10.76 ± 1.19 (median: 11; range: 8 to 13; IQR: 10 to 12). The values statistically increased at T₁₂ and T₃₆, where the mean values were 11.76 ± 1.10 (median: 12; range: 9 to 13; IQR: 11 to 12) and 11.83 ± 1.03 (median: 12; range: 9 to 14; IQR: 11 to 13).

CONCLUSION

MBL and soft tissue clinical parameters measured around two-piece hyperbolic-neck implants were stable during the 3-year follow-up and free from complications. The exposure of the hyperbolic neck for 1.0 to 1.5 mm allowed a flapless one-stage surgery, which supported fast adaptation of the soft tissues, evidenced by high PES values and low percentages of BOP. The results from the study imply a new simple approach in the clinical management of gingival and bone tissue.

A life-threatening floor of the mouth hematoma secondary to explantation attempt in the anterior mandible

<p>Implant dentistry is considered to be a safe and routine surgical procedure. However, cases of life-threatening hematoma of the floor of the mouth resulting in airway obstruction were previously reported as a complication of implant placement in the anterior mandible. Massive bleeding in this anatomical site may be caused by perforating the lingual cortex and/or damaging the lingual perimandibular vessels. In the long term, dental implants can fail, mainly due to peri-implantitis, and must be removed. Explantation procedure may occasionally become a complex challenge, with a risk for various complications.<br /> Case report: This report presents the first case of life-threatening hematoma of the floor of the mouth, as a complication secondary to a failed attempt of dental implant removal at the anterior mandible. The proximity of the implant to the lingual vascular canal might have served as a cause for vascular damage during explantation.<br /> Conclusions: Implant removal complications are scarcely described in the literature. Nonetheless, damaging blood vessels during explantation should not be underestimated. Computed tomography (CT) may be of value not only in preoperative implant planning but also before implant removal in jeopardized anatomical zones such as the anterior mandible. Lingual vascular canals should be looked for on computed tomography scans.</p>.

Is there an association between the use of antidepressants and complications involving dental implants? A systematic review and meta-analysis

The aim of this systematic review was to evaluate published evidence on the association between the use of antidepressants and complications involving dental implants. Two reviewers independently performed electronic searches of the MEDLINE/PubMed, Cochrane Library, and Scopus databases for relevant articles published up to May 30, 2019. This review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The Newcastle-Ottawa Scale was used for the appraisal of the methodological quality of the studies included. A meta-analysis was performed to determine the risk of dental implant failure in individuals taking antidepressants. Five comparative observational studies were selected for this review; these included a total of 2056 participants with 5302 implants. The results suggest a risk ratio of 3.73 (95% confidence interval 1.85-7.52, P=0.0002) for implant failure in antidepressant users submitted to oral rehabilitation when compared to non-users. However, these studies did not present methodological rigour or standardize the drugs used. Thus, there is insufficient evidence for an association between antidepressant use and dental implant complications.

Revisiting major anatomical risk factors of maxillary sinus lift and soft tissue graft harvesting for dental implant surgeons

The anatomical variations of the maxillary sinus septa, greater palatine artery, and posterior superior alveolar arteries might cause unexpected complications when they are damaged. Dentists who know these structures well might hope to learn more practical knowledge to avoid and assess injury preoperatively. Therefore, this review paper aimed to review the reported anatomy and variations of the maxillary sinus septa, greater palatine artery/nerve, and posterior superior alveolar artery, and to discuss what has to be assessed preoperatively to avoid iatrogenic injury. To assess the risk of injury of surgically significant anatomical structures in the maxillary sinus and hard palate, the operator should have preoperative three-dimensional images in their mind based on anatomical knowledge and palpation. Additionally, knowledge of the average measurement results from previous studies is important.

Implant stability in patients treated with platelet-rich fibrin and bovine bone substitute for alveolar ridge preservation is associated with peripheral blood cells and coagulation factors

AIMS

The aim of the present study was to assess the association between dental implant stability and peripheral blood cell composition and levels of coagulation factors in patients treated with alveolar ridge preservation with platelet-rich fibrin (PRF) and bovine bone substitute.

MATERIALS AND METHODS

Fifty patients were included between 2015 and 2017. PRF was prepared from autologous blood, in which blood cells and coagulation factor levels were measured. PRF and bovine bone were placed in the socket, followed by closure with PRF membrane. Implants were placed 14 (±2.5) weeks postextraction. The implant stability quotient was measured at t = 0, t = 10 days, t = 7 weeks, and t = 17 weeks by resonance frequency analysis.

RESULTS

Erythrocyte count was inversely associated with PRF membrane length, but not with implant stability. Conversely, platelet count did not correlate with membrane size but inversely correlated with implant stability at 7 and 17 weeks. In addition, implant stability was directly correlated with levels FXIII (t = 0, p < .01), active von Willebrand factor (VWF; t = 0 and 7 weeks, p < .05), and total VWF (t = 7 weeks, p = .012).

CONCLUSION

Implant stability following alveolar ridge preservation with PRF and bovine bone substitute is associated with circulating blood cells and coagulation factors. In particular, fibrin structure, VWF, and FXIII may be important modulators of implant stability.

Implant insertion torque and marginal bone loss: A systematic review and meta-analysis

Purpose: The purpose of this study was to examine the possible association between implant insertion torque and marginal bone resorption. Materials and methods: Electronic and manual searches were conducted for articles published up to and including March 2020. The databases consulted were MEDLINE (PubMed), Embase, Scielo and Cochrane Library. Meta-analyses were performed to evaluate the marginal bone resorption around dental implants placed with high insertion torque values (≥ 50 Ncm) compared to marginal bone resorption around dental implants placed with low to moderate (< 50 Ncm) insertion torque values. Results: A total of five prospective studies and two randomised clinical trials were included in the qualitative analysis. Three of them were analysed quantitatively. The meta-analyses did not show a statistically significant difference between the groups at 3, 6 or 12 to 15 months. Conclusions: No association between insertion torque value and peri-implant marginal bone resorption was found. Further studies of higher methodological quality are necessary to evaluate the possible correlation.

Maxillary sinus floor elevation using Beta-Tricalcium-Phosphate (beta-TCP) or natural bone: same inflammatory response

Sinus elevation is a common procedure to increase bone volume in the atrophic maxilla to allow placement of dental implants. Autogenous bone is the gold standard but is limited in quantity and causes morbidity at the donor site. β-TCP is a synthetic biomaterial commonly used in that purpose. It appears to induce a poor inflammatory response. This study aimed to evaluate the degree of edema of the sinus mucosa after sinus lift surgery according to the type of biomaterial. Forty sinuses (20 patients) were included retrospectively and divided into 2 groups according to the biomaterial that was used: synthetic biomaterial (BTCP group), natural bone (BONE group). A control group (CTRL group) was constituted by the non-grafted maxillary sinuses. Twelve measurements per sinus were realized on pre- and post-operative computed tomography and averaged to provide the sinus membrane thickness value (SM.Th). SM.Th was thicker post-operatively in the BTCP and BONE groups in comparison with the CTRL group and in comparison with pre-operative measurements. No difference was found post operatively between the BTCP and BONE groups. We found that a synthetic biomaterial (β-TCP) induced the same degree of edema, and thus of inflammation, as natural bone. It constitutes therefore an interesting alternative to autogenous bone for maxillary sinus lifts.

Prevention and management of life-threatening complications during dental implant surgery: a clinical case series

Complications can occur during implant placement; thus, clinicians should be aware of all potential outcomes, and staff members should be fully prepared to respond in case of emergency. A thorough medical history, precise surgical technique, knowledge, and skill are essential to prevent complications. The most serious complications, which could threaten the patient's life, are airway obstruction, bleeding, aspiration of the implant or its parts, infection, cavernous sinus thrombosis, nerve injury, and mandibular fracture.

The Effect of Dental Implant Collar Design on Crestal Bone Loss at 1 Year After Implant Placement

The aim of this randomized, prospective study was to compare clinical and radiographic outcomes of microtextured implants with two different collar designs at 1 year postplacement. A total of 69 implants were assessed in 58 patients for site, patient-specific, and clinician-experience variables. Overall implant survival was 94.9%. A statistically significant preservation of crestal bone was observed in the microgrooved-collar group. Narrow implant diameter was associated with a statistically significant increase in crestal bone loss. Collar design and implant diameter may be important in limiting adverse esthetic and bone loss outcomes during initial function.

Long-Term Follow-up of Iatrogenic Implant Endodontitis: A Case Report

An undesirable injury of adjacent teeth is one of many accidents that may occur during implant placement. Limited surgical access in a noncooperative patient can induce apical root transection. When endodontic pathosis is identified, root canal treatment is often initiated to prevent implant microbial contamination. This case report demonstrates the successful resolution of implant endodontitis by endodontic intervention without any surgical treatment in a patient presenting a moderate mental disorder.

A Randomized Controlled Clinical Trial Comparing Conventional and Computer-Assisted Implant Planning and Placement in Partially Edentulous Patients. Part 1: Clinician-Related Outcome Measures

The objectives of this study were to compare conventional and computer-assisted implant planning and placement (CAIPP) protocols regarding surgical planning predictability, intraoperative complications, and patient-centered outcomes. Partially edentulous patients (N = 73) were randomly allocated to one of three treatment groups: control (C, n = 26), with preoperative planning based on conventional radiography and freehand implant placement; and test 1 (T1, n = 24) and test 2 (T2, n = 23), with two different CAIPP protocols. The clinicians' predictions of the bony morphology, materials needed for surgery, and surgery duration were matched with intrasurgical findings using kappa tests. Complications or deviations from the surgical or prosthetic protocol were recorded. Descriptive statistics were used to study the sample sorted out by treatment group. Differences between groups were evaluated with chi-square test for qualitative variables and with nonparametric Kruskal-Wallis test for quantitative continuous variables. For post-hoc tests, the Bonferroni corrected (P < .016 = .05/3) Mann-Whitney test was used. CAIPP protocols showed better diagnostic potential than conventional protocols for the bone topography, need for simultaneous GBR procedures, membrane selection, and implant length predictions. The rate of surgical protocol deviations was similar in all groups, but their nature differed. Conventional protocols showed fewer splint-related incidences. Implant bed preparation and insertion could not be fully completed using the surgical splint in 3.8% of patients in C (1/26), 45.8% in T1 (11/24), and 47.8% in T2 (11/23). Deviation from the initial prosthetic plan was necessary in one case (T2; 4.4%). No biologic or technical complications were observed. CAIPP protocols showed a higher diagnostic potential than conventional protocols. A high incidence of intraoperative surgical protocol modifications to adjust suboptimal implant placements was reported for every group. Therefore, strict intraoperative implant position monitoring is mandatory for both treatment protocols.

Microchemical and Micromorphologic ESEM-EDX Analysis of Bone Mineralization at the Thread Interface in Human Dental Implants Retrieved for Mechanical Complications After 2 Months to 17 Years

The aim of this study was to analyze the degree of mineralization around nine clinically stable titanium dental implants retrieved after 2 months to 17 years for mechanical complications from five patients. The micromorphology and microchemistry of the interface bone at the coronal and apical sides of the threads were analyzed by environmental scanning electron microscope and energy-dispersive X-ray spectroscopy (EDX) on histologic samples. Mineralization was investigated by atomic calcium-to-nitrogen (Ca/N), phosphorous-to-nitrogen (P/N), and calcium-to-phosphorous (Ca/P) ratio evaluation (statistical analysis by two-way analysis of variance with Student-Newman-Keuls; P < .05). EDX showed higher Ca/N, P/N, and Ca/P values for the bone at the coronal side compared to the apical side of the threads in the long-term (≥ 14 years) samples. The two most significant findings were that (1) the interface bone located at the coronal side of the implant threads was generally more mineralized than the interface bone located at the apical side, and (2) the mineralization of the peri-implant bone at the interface increased over time. A higher degree of mineralization was found at 2 months in an immediately loaded implant when compared to the 2-month submerged unloaded control, likely related to the different remodeling events (coronal vs apical side of the implant threads) due to the direction of the loading forces.

Clinical research on a flapless surgical technique application of narrow implants

The aim of the present study was to investigate the role of Axiom (implant diameter) ø2.8 mm narrow body implant in the clinical effect of minimally invasive implants in edentulous space.This study included 10 patients with 10 edentulous spaces less than 5 mm and received minimally invasive surgery with 10 Axiom ø2.8 mm narrow implants. Re-stabilization of all implants began 6 months after surgery to fix the partial denture. All cases were followed up for clinical and panoramic X-ray examinations.Imaging examination on these 10 pieces of narrow implants after 6 months showed that implant alveolar bone crest average absorption amount was 0.20 mm and no implant peripheral inflammation mucositis and denture with adjacent teeth gingival papilla between the fillings. All patients felt strong mastication and the reparation effect was more than up to expectation. No implant loosening and shedding were observed.Hence, <5 mm edentulous space by Axiom ø2.8 mm implant minimally invasive reparation can be used for aesthetic purposes.

Biological and technical complications of tilted implants in comparison with straight implants supporting fixed dental prostheses. A systematic review and meta-analysis

OBJECTIVES

To evaluate the implant failure, marginal bone loss (MBL), and other biological or technical complications of restorations supported by tilted and straight implants after at least 3 years in function.

METHODS

Electronic and manual searches were performed in MEDLINE, Embase, Web of Science, and OpenGrey to identify clinical studies published up to December 2017. After duplicate study selection and data extraction, the risk of bias was assessed with the ROBINS-I tool. Random-effects meta-analyses of relative risks (RRs) or mean differences (MD) and their 95% confidence intervals (CIs) were performed, followed by subgroup/sensitivity analyses and application of the GRADE approach.

RESULTS

A total of 17 nonrandomized studies (eight prospective/nine retrospective) were included. The number of implants of the overall systematic review was 7,568 implants placed in 1,849 patients supporting either full-arch or partial implant prostheses. No difference in the failure of tilted and straight implants was seen (eight studies; 4,436 implants; RR = 0.95; 95% CI = 0.70 to 1.28; p = 0.74), with the quality of evidence being very low due to bias and imprecision. Likewise, no difference in MBL was seen between tilted and straight implants (16 studies; 5,293 implants; MD = 0.03 mm; 95% CI = -0.03 to 0.10 mm; p = 0.32), with the quality of evidence being very low due to bias and inconsistency. Contradictory results regarding implant survival were found from prospective and retrospective studies, which could indicate bias from the latter.

CONCLUSIONS

Within the limitations of the present systematic review, no effect of implant inclination on implant survival or peri-implant bone loss was found.

10 Keys for Successful Esthetic-Zone Single Implants: Importance of Biotype Conversion for Lasting Success

The concept of 10 keys for successful esthetic-zone single immediate implants is an evidenced-based summary for the treatment planning and replacement of a hopeless tooth in the maxillary anterior sextant. It includes two treatment-planning, five surgical, and three prosthetic keys. These keys are aimed at minimizing soft- and hard-tissue complications to achieve an optimal long-term esthetic implant restoration. Based on the 10 keys, which were described in a prior publication and are reiterated herein, the management of an immediate implant in the esthetic zone is considered a complex SAC procedure (SAC = straightforward, advanced, and complex). The present article highlights the importance of connective tissue grafting as part of the 10 keys and its role in biotype conversion and esthetic success that endures.

Surgical Alternatives for Treating Peri-implantitis

The objective of this case series was to describe surgical approaches that can be used to efficiently and effectively treat peri-implantitis as measured by positive changes in clinical parameters. A total of 32 patients with 45 implants were treated surgically to eliminate peri-implantitis. Baseline clinical parameters measured prior to surgery were compared to those made 6 months postsurgery to evaluate the efficacy of each procedure. Implants demonstrating signs of peri-implantitis were treated by one of three approaches: (1) regenerative surgery, (2) osseous resective surgery, or (3) apically repositioned flap surgery. In all instances, the exposed implant surfaces were debrided and decontaminated. Relative to baseline values, regenerative surgery yielded statistically significant changes in probing depth (PD) (7.21 ± 0.27 mm to 4.09 ± 0.14 mm) and percentage of sites exhibiting bleeding on probing (BoP) (100.0% ± 0.0% to 10.6% ± 3.3%) as measured at the 6-month recall visit (P ≤ .05). The decrease in probing depth was not dependent on the type of graft material used (P ≤ .05). Resective surgery yielded statistically significant changes in PD (5.86 ± 0.23 mm to 3.63 ± 0.14 mm) and the percentage of sites exhibiting BoP (100.0% ± 0.0% to none) (P ≤ .05). Finally, the implants treated via apically repositioned flap surgery demonstrated statistically significant decreases (P ≤ .05) in both PD (6.79 ± 0.27 mm to 4.32 ± 0.16 mm) and BOP (100.0% ± 0.0% to 14.3% ± 6.7%) (P ≤ .05). Regenerative, resective, and apically positioned flap surgery can be utilized to successfully treat peri-implantitis.

Complications and Management of Implants Migrated into the Maxillary Sinus

The article describes complications following dental implant dislocation into the maxillary sinus and their management and attempts to elucidate the reasons for these complications and their prevention. This retrospective study presents 55 cases of dental implant migration into the maxillary sinus. Patients were 30 men and 25 women with average age of 58 years. Oroantral communication was found in 46 cases, primarily in cases without prior bone augmentation, in patients aged older than 60 years (mean), and medically compromised patients (ASA > 1). The dislocated implant and the infected tissue were removed from the sinus in most cases by Caldwell-luc intervention. The oroantral communication was closed by local and regional flaps. In most of the cases, the oroantral communication was closed by a single intervention. The conclusion was that oroantral communication and maxillary sinusitis are common findings following dental implant migration and dislocation into the maxillary sinus. The risk factors for these complications were dental implantation in the posterior maxilla without sufficient alveolar bone, implantation without prior maxillary sinus augmentation, and older and medically compromised patients. Successful closure of the communication is usually performed with local or regional flaps.

Comparative evaluation of soft and hard tissue changes following endosseous implant placement using flap and flapless techniques in the posterior edentulous areas of the mandible-a randomized controlled trial

BACKGROUND

Dental implant-supported restorations have long been used as a successful modality for replacing missing teeth. There are two well-established methods of implant placement. The traditional approach to implant surgery involves raising a mucoperiosteal flap and the alternative approach does not involve reflecting a flap, each having its own advantages and disadvantages. The purpose of the present study was to compare and evaluate the soft and hard tissue changes around endosseous implants placed using flap and flapless surgery in mandibular posterior edentulous sites over a period of time.

MATERIALS AND METHODS

A total of 20 systemically healthy patients with a single edentulous site in the posterior mandible were enrolled in this study and 20 endosseous implants were placed (10 in the flap group and 10 in the flapless group). The peri-implant probing depth was assessed. Radiographic assessment was done for changes in the marginal bone levels at the mesial and distal side of the implant with measurements made at baseline, 6 months, and 12 months. Patient-centered outcomes were assessed by using the visual analogue scale (VAS). All these parameters were statistically analyzed using the Wilcoxon signed-rank test, paired Student t test, and two-way ANOVA test and were considered to be significant if the p value was ≤ 0.05.

RESULTS

Twenty patients were enrolled in the present study and endosseous implants were placed. Eighteen subjects were followed up throughout the study period and two patients were excluded from the study. The mean PD in the flapless group was comparatively less than the flap group at 12 months and was found to be statistically significant. During the observation period of 12 months, reduction of crestal bone height around the implants placed by flapless and flap surgery were statistically significant. The flapless group showed less change in the crestal bone height which was statistically significant compared to the flap group. The mean VAS score on day 0 in the flap and flapless group was statistically significant. The flapless group showed significantly less pain when compared to the flap group.

CONCLUSION

Although the flapless technique of endosseous implant placement had statistically significant less PD, bone loss, and pain than the flap technique, the difference was found to have uncertain clinical significance.

Peri-implant bone loss clinical and radiographic evaluation around rough neck and microthread implants: a 5-year study

OBJECTIVE

To evaluate marginal bone loss over 5 years around microthreaded implants placed in the maxillary anterior/esthetic zone and immediate restored with non-occlusal loading.

MATERIALS AND METHODS

Seventy-one implants (with microthreads up to the platform-rough surface body and neck, internal connection and platform switching) were placed in healed bone in the maxillary arches of 30 men and 23 women (mean age 37.85 ± 7.09 years, range 27-60). All subjects had at least 3 mm of soft tissue to allow the establishment of adequate biologic width and to reduce bone resorption. Each patient received a provisional restoration immediately after implant placement with slight occlusal contact. Mesial and distal bone height was evaluated using digital radiography on the day following implant placement (baseline) and after 1, 2, 3, 4 and 5 years. Primary stability was measured with resonance frequency analysis.

RESULTS

No implants failed, resulting in a cumulative survival rate of 100% after 3 years. Marginal bone loss from implant collar to bone crest measured at baseline (peri-implant bone defect at the fresh extraction socket) and after 5 years was 0.90 mm ± 0.26 mm. Mesial and distal site crestal bone loss ranged from 3.42 ± 1.2 mm at baseline to 3.51 ± 1.5 mm after 5 years and from 3.38 ± 0.9 mm at baseline to 3.49 ± 0.9 mm after 5 years, respectively (P = 0.086).

CONCLUSIONS

The results of this study showed limited implant crestal bone loss 0.90 mm ± 0.26 mm and 100% of implant survival rate at 5-year follow-up of immediate restored implants with rough surface neck and microthreads.

Diagnostic performance of cone beam computed tomography in assessing peri-implant bone loss: A systematic review

OBJECTIVES

To evaluate the diagnostic performance of cone beam computed tomography (CBCT) in the assessment of peri-implant bone loss and analyze its influencing factors.

MATERIALS AND METHODS

Clinical and preclinical studies reporting diagnostic outcomes of CBCT imaging of peri-implant bone loss compared to direct reference measurements were sought by searching five electronic databases, PubMed, MEDLINE, EMBASE, Web of Science, and CINAHL Plus, and OpenGrey. QUADAS-2 criteria were adapted for quality analysis of the included studies. A qualitative synthesis was performed. Two meta-analysis models (random-effects and mixed-effects) summarized the area under receiver operating characteristic (AUC) curve observations reported in the selected studies. The mixed-effects meta-analysis model evaluated three possible influencing factors, "defect type," "defect size," and "study effect."

RESULTS

The initial search yielded 3,716 titles, from which 18 studies (13 in vitro and 5 animal) were included. Diagnostic accuracy of CBCT was fair to excellent in detecting in vitro circumferential-intrabony and fenestration defects, but moderate to low for peri-implant dehiscences, and tended to be higher for larger defect sizes. Both, over- and underestimation of linear measurements were reported for the animal models. The meta-analyses included 37 AUC observations from eight studies. The random-effects model showed significant heterogeneity. The mixed-effects model exhibited also significant but lower heterogeneity, and "defect type" and "study effect" significantly influenced the variability of AUC observations.

CONCLUSION

In vitro, CBCT performs well in detecting peri-implant circumferential-intrabony or fenestration defects but less in depicting dehiscences. Influencing factors due to other site-related and technical parameters on the diagnostic outcome need to be addressed further in the future studies.

Development of mirror pain following trigeminal nerve injury: a case report and review of neuropathic mechanisms

Following injury to a peripheral nerve, patients may complain of pain over the distribution of the same contralateral nerve, a phenomenon referred to as contralateral pain or mirror pain (MP). Symptoms of MP usually begin after the neuropathic pain from the original nerve injury has become chronic. Chronic neuropathic pain can lead to sensitization and spread of pain. Because the diagnosis of MP can be missed, patients may undergo multiple treatment procedures that prove to be ineffective in relieving the pain. This article presents a case of MP that appeared approximately 20 months following inferior alveolar nerve injury that occurred during placement of a dental implant in the region of the first molar. Acutely painful nerve injuries must be aggressively treated to prevent changeover to a chronic pain state characterized by sensitization and spread of pain beyond the initial injury. Consequently, clinicians need to begin effective, early pain management to prevent the changeover to chronic pain that has become centralized and refractive to treatment.

Implant-supported prosthesis treatment planning aspects of Kaunas city dentists and dental specialists

OBJECTIVE

Rehabilitation of mastication using fixed or removable prosthesis on dental implants is a daily procedure in modern dentistry.The huge variety of diagnostic tools and methods, such as cone beam computed tomography or surgical guides help to avoid complications. A vast quantity of diagnostic tools and prosthesis require a tight communication between surgeons and prosthodontists in order to achieve better treatment plan.

METHODS

The questionnaire was approved by LUHS Committee of Ethics. A questionnaire of 17 demographic and specialized questions was composed. A randomized survey of dentists and dental specialists was conducted in Kaunas. A statistical analysis was performed using χ²test and Student's T-test criteria.

RESULTS

Most of correspondents believe that treatment plan should be created by the current dentist, regardless his/hers specialization. All correspondents performing dental implantation, use elevation of mucoperiosteal flap. The most common diagnostic tool among dentists and oral surgeons is panoramic x-ray. The most common diagnostic tools between prosthodontists are panoramic x-ray and analysis of dental stone castings. The most common complications among dentists and prosthodontists are improper adjustment of soft tissue and errors of dental technicians, among oral surgeons - improper adjustment of soft tissues and implant position.

CONCLUSIONS

1. The creation of treatment plan does not depend on specialization of dentist. 2. The elevation of mucoperiosteal flap is more common than non-flap procedure. 3. The most used diagnostic method is panoramic x-ray. 4. The most prevalent complications are improper adjustment of soft tissues and errors of dental technicians.