Cone-beam computed tomography assessment of maxillary anterior alveolar bone remodelling in extraction and non-extraction orthodontic cases using stable extra-alveolar reference.

OBJECTIVE: To explore alveolar cortical positional change in response to tooth movement in extraction and non-extraction orthodontic cases, using cone-beam computed tomography (CBCT) and stable extra-alveolar references. MATERIALS AND METHODS: The pre-treatment (T1) and post-treatment (T2) CBCT scans of 25 extraction (EXT) and matched 25 non-extraction (Non-EXT) orthodontic cases were imported into Dolphin Imaging 3D, and oriented uniformly. Sagittal and axial CBCT cross-sections were traced using customized software-generated guides. The displacement of teeth and alveolar bone cortices were automatically measured using the palatal plane (PP) and the line perpendicular to PP and passing Sella as reference. Intra- and inter-group differences between T1 and T2 were analysed. Subjects were also superimposed three-dimensionally using Geomagic Control X for qualitative analysis of cortical remodelling. RESULTS: The EXT group showed incisor retraction, while the Non-EXT group exhibited statistically significant incisor anterior tipping (P < .05). In EXT, both the labial and palatal cortices are resorbed. Non-EXT showed labial cortex anterior modelling, and statistically significant palatal cortex resorption (P < .05). In both groups, statistically significant decrease in total and palatal alveolar widths, increase in labial widths, and palatal dehiscence were observed. Comparatively, EXT showed significantly more incisal total and palatal width decrease and palatal vertical bone loss. CONCLUSION: Labial cortical remodelling was shown to follow anterior tooth movement, but the palatal cortical response to incisor retraction and labial cortical remodelling in general remained inconclusive. Narrowing of the alveolar housing and palatal dehiscence were observed regardless of extraction following orthodontic treatment.

Maxillary Sinus and Surrounding Bone Anatomy With Cone Beam Computed Tomography After Multiple Teeth Loss: A Retrospective Multicenter Clinical Study.

PURPOSE: The aim of this multicenter study was to examine the residual alveolar bone anatomy and sinus mucosa pattern at maxillary sinus regions in multiple teeth loss. MATERIALS AND METHODS: This study was conducted with cone beam computed tomography images of 518 patients (267 females and 251 males) with multiple posterior maxillary teeth loss. Variables associated with sinus membrane (SM), sinus dimensions, ostium, septa, sinus neighborhood, alveolar bone height and ridge width, posterior superior alveolar artery, and adjacent roots were evaluated. RESULTS: No (58.2%) or flat (19.3%) thickening morphology was detected at most of the SMs. Membrane thickening and mucosal-like morphology was more prevalent for male patients (P = 0.005). The mean sinus width was relatively low (3.64 ± 3.33 mm) at the 5-mm level and showed an expected increase toward upper levels. Most of the sinus spaces were dimensionally average (39.5%) or wide (44.7%), and no effect of gender was observed in terms of sinus dimensions (P > 0.05). CONCLUSION: Multiple teeth loss plays a role in creating an imaginary sinus anatomy constituted of a relatively narrow space compared with single-tooth loss cases, from 3.6-mm mean coronal width to 11.3 mm in the apical portion.

Anatomic Variation of Posterior Superior Alveolar Artery: Review of Literature and Case Introduction.

The objective of this article is to review topography of posterior superior alveolar artery (PSAA), and to present a case with visualization of a rare anatomic variation of PSAA. An electronic search was undertaken to identify articles about topography of PSAA in Medline, Embase, and Google Scholar databases, published between January 1977 and December 2017. Two animal studies, 8 cadaver studies, 18 cone-beam computerized tomography (CBCT) studies, and 2 review articles were found. The animal studies, cadaver studies, and review articles were excluded because they were not about topography of PSAA. Only CBCT studies were included in this review. Accurate knowledge of vital structures in the surgical area is critical during surgical procedures. PSAA should be analyzed during planning sinus lifting with lateral approach. In the present case, a detailed evaluation of patient by CBCT provided the opportunity to find out a rare variation of PSAA with multiple vessels.

Transplantation of Autogenous Bone Block With an Osseointegrated Implant: Seedling Technique With Twelve-Month Follow-Up.

OBJECTIVE: Loss of teeth frequently results in compound horizontal and vertical alveolar bone defects. An appropriate bone structure is the key for implant placement and bony support of soft tissues. Advanced bone augmentation techniques are required for the reconstruction of these defects. This report will present a new bone block grafting technique with 12-month follow-up. METHOD: The seedling technique was used to augment the alveolar bone 3-dimensionally with autologous bone block and an osseointegrated implant in a 2-stage procedure. Horizontal and vertical bone loss is revealed after cone beam radiographic examination in the right maxillary lateral incisor area. Initially, the implant was placed at the right maxillary tuber area, where the bone was abundant. After 2-months healing phase, the osseointegrated implant was harvested with the surrounding bone and transplanted to the anterior region of maxilla to augment the horizontal and the vertical components of the recipient site. Transplanted implant inserted into autogenous bone block was fixed with mini plate to the adjacent native bone. Prosthetic restoration was applied 4 months after the transplantation. RESULTS: Seven months after the first surgery, treatment of anterior bone deficiency was accomplished. The patient was fully satisfied with the function and the esthetics of the restoration. The radiological and clinical examinations at 1-year follow-up evaluation showed successful outcome of transplanted autogenous bone block without any resorption. CONCLUSION: This clinical report demonstrated that anterior maxillary single-tooth replacement, according to seedling concept of autogenous bone block with osseointegrated implant, is a successful and predictable treatment modality.

Validation of Therapeutic Anatomy-Oriented Classification in Endosseous Dental Implant Treatment: A Pilot Study.

BACKGROUND: The purpose of the study was to validate a newly proposed therapeutic anatomically based clinical and radiological classification for dental implant treatment. METHODS: Eighty-one patients with at least 1 edentulous jaw segment (EJS) from 2 dental clinics were included in this study. Both clinical and radiological parameters were assessed in aesthetic and nonaesthetic zones. The data were then compared at preoperative, intraoperative, and postoperative (subdivided into early and late stage) study stages. RESULTS: Based on the hard and soft tissue support, EJSs were divided into 3 types. The outcomes were then validated at preoperative, intraoperative, and early postoperative stages. Data were then analyzed using paired sample t test and the Wilcoxon signed ranks test. No statistically significant difference (P > 0.05) was identified between any the measurements. CONCLUSIONS: The proposed therapeutic anatomically based clinical and radiological classification for the dental implant treatment seems to be reproducible, objective, and helpful in planning dental implant treatment. Future studies with a larger sample size are needed to further validate the outcome obtained in this pilot study.

Implant-Site Related and Patient-Based Factors With the Potential to Impact Patients' Satisfaction, Quality of Life Measures and Perceptions Toward Dental Implant Treatment.

OBJECTIVES: The present study aimed at evaluating both the implant site-related and patient-based factors with the potential to affect the extent of patients' satisfaction and also their perceptions regarding dental implant treatment. Potential differences between the esthetic evaluations of dental patients and dental specialists were also considered. MATERIALS AND METHODS: Implant-supported fixed prosthesis (n = 164) in 264 anterior esthetic implant sites were included. Patients' satisfaction, esthetic considerations, and perceptions toward dental implants, were evaluated by both Oral Health Impact Profile-14 (OHIP-14) questionnaire and visual analog scale. Pink Esthetic Score/White Esthetic Score were used for the professional esthetic evaluations of dental specialists. RESULTS: Overall patient satisfaction was high (87.42 ± 11.86). Compared with implant supported single-tooth restorations, patients with implant-supported bridges had lower OHIP scores (P = 0.001) and were relatively less satisfied with particular aspects of dental implant treatment (eg, cleanability, phonetics, surgical discomfort, and pretreatment information). Generally, type of prosthesis, history of soft/hard tissue augmentation, and reason for tooth loss had a clear impact on the extent of patients' satisfaction, esthetic considerations regarding treatment outcome, and their perceptions toward dental implant treatment (P < 0.05). CONCLUSIONS: Fixed implant-supported restorations generally provide with high levels of satisfaction and oral health-related quality of life.

Evaluation of Single Tooth Loss to Maxillary Sinus and Surrounding Bone Anatomy With Cone-Beam Computed Tomography: A Multicenter Study.

BACKGROUND: Posterior maxillary tooth loss may complicate the implant treatment due to the alterations in alveolar anatomy and maxillary sinus pneumatization. This study aimed to comprehensively examine the anatomical structure of this region from cone-beam computed tomography (CBCT) images. MATERIALS AND METHODS: The posterior maxilla regions with single tooth loss were analyzed by dividing the variables into 3 subgroups from images of 597 patients chosen from 1160 CBCTs. Variables associated with sinus membrane (SM), sinus dimensions, ostium, septa, sinus neighborhood, alveolar bone height (ABH) and width (RW), posterior superior alveolar artery (PSAA), and adjacent roots were evaluated. RESULTS: The majority of the patients demonstrated 0 to 5 mm membrane thickness. Irregular SM thickening was lower for female patients. While females showed higher number of narrow sinus, males had higher RW than females. Sinus augmentation classification showed negative correlation with ABH, root-tip sinus floor and edentulous site classification. Posterior septa height was correlated with number of septa and ABH. PSAA diameter and location were also correlated between each other. CONCLUSION: The present results define formation of a sinus space with 11 mm coronal and 16 mm apical width after single tooth loss. A flat or semispherical thickening around 4 mm is usual in most cases with 51% possibility of anterior septum existence. A ridge anatomy, around 7.5 mm ABH and 7.2 to 9.3 RW from coronal to apical, complements this anatomy. Further studies are needed to clarify the reasons behind the SM and crestal anatomy variations between genders.

Apical/Retrograde Periimplantitis/Implant Periapical Lesion: Etiology, Risk Factors, and Treatment Options: A Systematic Review.

OBJECTIVES: To review the literature on retrograde periimplantitis symptoms, risk factors, and treatment methods and to propose a decision-making tree of retrograde periimplantitis management. MATERIALS AND METHODS: An electronic literature search was conducted on the MEDLINE and EMBASE databases for articles published between 1990 and 2015. Clinical human studies in the English language were included. RESULTS: The search resulted in 44 case reports published by 27 authors. The average time of the diagnosis of the pathology was found to be 26.07 weeks after implant placement (SD ± 39.7). Fistula formation was found to be the most common clinical symptom, statistically significantly more often occurring in the maxilla (P = 0.04). A negative correlation was found between pain and the adjacent tooth with incomplete endodontic treatment/endodontic pathology (r = -0.4; P = 0.009) and a positive correlation between the later risk factor and implant removal (r = 0.3; P = 0.028). Regenerative treatment (45.2% of the cases) or implant removal (35.7% of the cases) was the most common treatment techniques used. A decision-making tree of retrograde periimplantitis management is suggested. CONCLUSIONS: The etiology of retrograde periimplantitis is most often infectious. A decision-making tree aimed at managing patients with retrograde periimplantitis according to the possible etiology and symptoms of the disease can be a useful tool in the treatment of the pathology.

Radiographic Fractal and Clinical Resonance Frequency Analyses of Posterior Mandibular Dental Implants: Their Possible Association With Mandibular Cortical Index With 12-Month Follow-up.

BACKGROUND: The aim of the present study was to investigate whether the mandibular cortical index (MCI) has a relationship with fractal dimension of bone and/or implant stability, and to justify the possible association between MCI, fractal dimension, and stability. MATERIALS AND METHODS: Eighty-two subjects who received dental implants to replace missing mandibular premolar/molar sites were selected. Three months after surgical placement, implants were restored with fixed ceramic fused metal crowns. MCI was evaluated at baseline; fractal dimensions were measured with fractal analysis (FA) and implant stability quotient (ISQ) with resonance frequency analysis immediately after surgery and 12-month follow-up. RESULTS: FA at mesial and distal regions for Class 1, Class 2, and Class 3 MCI resulted with significant increases at 12-month follow-up compared to baseline. The ISQ in patients with Class 2 and Class 3 MCI resulted with a significant decrease compared to Class 1 MCI at baseline and at 12 months. All MCI classes evaluated with ISQ and FA at baseline values resulted with significant increases at 12 months. Significant correlations were considered for all mandibular posterior implants between baseline and 12-month measurements for ISQ and FA evaluations. CONCLUSIONS: Fractal analysis may be a useful method for understanding the healing process around implants and implant stability quotient values. Mandibular cortical index evaluations should be considered before implant procedures, which may provide a presurgical treatment plan and may provide information about the mandibular bone quality.

30-Year Outcomes of Dental Implants Supporting Mandibular Fixed Dental Prostheses: A Retrospective Review of 4 Cases.

PURPOSE: The aim of this study was to present the 30-year outcomes of 28 implants supporting mandibular screw-retained fixed dental prostheses (FDPs). MATERIALS AND METHODS: Dental charts of the 4 patients were carefully reviewed, and it was noticed that they received 28 implants and 5 screw-retained FDPs in 1983 and 1984. The chief concerns raised by these patients were poor retention of their complete dentures and decreased masticatory function at the time of treatment planning. Each dental care they received was recorded in the last 30 years. Implant survival, radiographic, and prosthodontic examinations were performed. RESULTS: No implants were lost after 30 years, giving the implant a survival rate of 100%. The average marginal bone level was 2.6 ± 0.5 mm at the last recall appointment. Of the 5 FDPs delivered, 1 needed replacement, indicating a prosthesis survival rate of 80%. The patients needed 21 repairs such as replacement of denture teeth/gold screws and hard relining, and 19 adjustments such as occlusal adjustments and acrylic resin contouring, over 30 years. CONCLUSION: This clinical report shows that machined-surface dental implants can successfully support screw-retained fixed dental prostheses for over 30 years, making dental implants an important dental treatment alternative compared to the traditional prosthetic treatment methods.

Intraoral use of extraoral implants for oral rehabilitation of a pediatric patient after resection of ewing sarcoma of the mandible and reconstruction with iliac osteocutaneous free flap.

Large osseous defects secondary to resection of the mandibular segment may lead to significant facial deformity, functional disabilities, and associated psychologic problems. The therapeutic approach is more complicated in pediatric patients because it must not interfere with normal craniofacial growth process. Here, we present a clinical report to emphasize the application of extraoral short implants with magnetic abutments used for mandible of a growing patient reconstructed with free iliac flap after resection of Ewing sarcoma. A 5-year-old boy, complaining of an ulcerated mass of the anterior mandibular area and floor of the mouth, was referred to our clinic. Incisional biopsy from the lesion confirmed the diagnosis of Ewing sarcoma. After resection, free iliac osteocutaneous flap, with a 6.5 × 4.0-cm skin paddle and based on the deep circumflex iliac vessels, was used to reconstruct the mandibular integrity and to cover the floor of the mouth simultaneously. Nine months after the operation, the patient was referred for oral rehabilitation. Prosthodontic plan included the placement of 5 extraoral implants with magnetic abutment and fabrication of an implant-retained overdenture. Magnetic abutment was preferred not to interfere with the expected craniofacial growth. During a follow-up period, radiographic images showed no pathologic signs with consideration of overall bone loss and recurrence of the tumor; 12 months after the initiation of prosthetic loading, no peri-implant bone loss was observed. In conclusion, this reported case would be an example for the management of challenging pediatric mandibular tumor cases in terms of resection, reconstruction and dental rehabilitation.

Effect of history of periodontitis on implant success: meta-analysis and systematic review.

PURPOSE: To determine if there is a relationship between history of periodontitis and dental implant success (used marginal bone loss [MBL] as the assessment criteria) and survival rates. MATERIALS AND METHODS: PubMed search was performed in the period between 2002 and 2012. Studies qualified for the inclusion should have ≥5 years followed-up and reported the incidence of peri-implantitis and/or implant survival and/or MBL in patients with and without a history of periodontitis. A meta-analysis was performed using the random-effects model on the selected qualified articles. RESULTS: All the 14 studies showed better implant survival rates for non-periodontitis patients' group. Six of 10 studies reported statistically significantly higher MBL and prevalence of peri-implantitis among periodontitis patients. Our meta-analysis did not find implant survival rates to be significantly lower among periodontitis patients (P = 0.99) but revealed a history of periodontitis to be significantly related to the higher prevalence of peri-implantitis (P < 0.001). CONCLUSIONS: There is no difference, in terms of implant survival rate, between periodontitis and non-periodontitis patients. However, patients with history of periodontitis had lower implant success rate (more MBL and incidence of peri-implantitis) when compared with non-periodontitis patients.

Evaluation of mandibular lingual foramina related to dental implant treatment with computerized tomography: a multicenter clinical study.

BACKGROUND: Bleeding can be one of the severe complications during implant placement or other surgeries. Presurgical assessment of the area should be performed precisely. Thus, we examined lingual vascular canals of the mandible using dental computerized tomography (CT); define the anatomical characteristics of canals and the relationship with mandibular bone. METHODS: One thousand sixty-one foramina in 639 patients, in 5 dental clinics, were included in this multicenter study. Distance between crest and lingual foramen, tooth apex and lingual foramen, distance from mandibular border, diameter of lingual foramen, canal type, anastomosis, and location of foramen were examined. RESULTS: Foramen was 18.33 ± 5.45 mm below the bony crest and 17.40 ± 7.52 mm from the mandibular border, with men showing larger measurements. The mean diameter of lingual foramina was 0.89 ± 0.40 mm; 76.8% canal type was mono; 51.8% patients presented with median lingual canal-foramen (MLC) and 21.1% with lateral lingual foramen. Diameter of MLC was statistically larger. CONCLUSIONS: With a large sample group, results represented that lingual foramina could be visualized with dental CT, providing useful data for mandibular implant surgeries. Findings suggest that vascular canals and several anastomoses exist in the anterior mandible extending through premolar and molar regions as well. It is imperative to consider these vessels with the dental CT before and during the mandibular surgery to prevent threatening hemorrhage.

The impact of handicap severity on oral and periodontal status of patients with mental retardation.

AIM: Mental retardation (MR) subjects comprise a considerable amount of the community and are susceptible to oral and periodontal problems due to insufficient oral care. The aim of this cross-sectional study was to determine the oral health and periodontal status of MR patients in Turkey with regard to periodontal indices and Decay missed filling teeth (DMFT) scores and compare findings according to severity of the MR. MATERIALS AND METHODS: One hundred and five MR patients were included to the study and divided into 3 groups according to MR severity diagnoses. Demographic variables like age, gender, disabled sibling, BMI, living an institution and clinical parameters like plaque index (PI), gingival index (GI), bleeding on probing (BOP), probing depth (PD), clinical attachment level (CAL), missing teeth and DMFT scores were recorded from all subjects. Appropriate statistical analyses were used to compare the findings. RESULTS: There were no statistically significant differences between groups according to age, gender, disabled sibling, living status and DMFT scores. Clinical periodontal indices and the number of missing teeth were showed a statistically significant increasing trend with the severity of MR (p < 0.05). Correlation analysis showed significant positive correlations between PI and periodontal disease measures like GI, PD, CAL and BOP and also between PI and DMFT (p < 0.05). CONCLUSION: The deteriorated teeth condition and deprived periodontal health of MR patients may be most likely caused by the poor oral hygiene and may be worsen with the severity of the MR. Clinical significance: Knowledge of oral and periodontal status of mental retardation patients has great importance for public health and family education.

Indications for implant-supported rehabilitation of the posterior atrophic maxilla: A multidisciplinary consensus among experts in the field utilising the modified Delphi method.

PURPOSE: To establish consensus-driven guidelines that could support the clinical decision-making process for implant-supported rehabilitation of the posterior atrophic maxilla and ultimately improve long-term treatment outcomes and patient satisfaction. MATERIALS AND METHODS: A total of 33 participants were enrolled (18 active members of the Italian Academy of Osseointegration and 15 international experts). Based on the available evidence, the development group discussed and proposed an initial list of 20 statements, which were later evalu-ated by all participants. After the forms were completed, the responses were sent for blinded ana-lysis. In most cases, when a consensus was not reached, the statements were rephrased and sent to the participants for another round of evaluation. Three rounds were planned. RESULTS: After the first round of voting, participants came close to reaching a consensus on six statements, but no consensus was achieved for the other fourteen. Following this, nineteen statements were rephrased and sent to participants again for the second round of voting, after which a consensus was reached for six statements and almost reached for three statements, but no consensus was achieved for the other ten. All 13 statements upon which no consensus was reached were rephrased and included in the third round. After this round, a consensus was achieved for an additional nine statements and almost achieved for three statements, but no consensus was reached for the remaining statement. CONCLUSION: This Delphi consensus highlights the importance of accurate preoperative planning, taking into consideration the maxillomandibular relationship to meet the functional and aesthetic requirements of the final restoration. Emphasis is placed on the role played by the sinus bony walls and floor in providing essential elements for bone formation, and on evaluation of bucco-palatal sinus width for choosing between lateral and transcrestal sinus floor elevation. Tilted and trans-sinus implants are considered viable options, whereas caution is advised when placing pterygoid implants. Zygomatic implants are seen as a potential option in specific cases, such as for completely edentulous elderly or oncological patients, for whom conventional alternatives are unsuitable.

Is there a gender difference in anatomic features of incisive canal and maxillary environmental bone?

OBJECTIVES: The effect of gender on anatomic structures and various body systems were illustrated in the literature. The purpose of this study was to identify the influence of gender and tooth loss on incisive canal characteristics and buccal bone dimensions in the anterior maxilla. MATERIALS AND METHODS: Computed tomographies (CTs) of 417 male and 516 female patients in four dental clinics were included in this study. The diameter and the length of the incisive canal; width and the length of the bone anterior to the canal; palatal bone length, root length, and root width of the central incisor teeth were measured and recorded from CT sections. RESULTS: Mean incisive canal length was 11.96 ± 2.73 mm and 10.39 ± 2.47 mm in men and women, respectively, (P < 0.05). In men, mean canal diameter was 2.79 ± 0.94 mm whereas in women it was 2.43 ± 0.85 mm and this difference was statistically significant (P < 0.05). Men had significant higher buccal bone dimensions (length and width of the bone anterior to the canal) than women. Absence of teeth in the anterior maxilla decreased incisive canal length and buccal bone dimensions; however, canal diameter remain unchanged. CONCLUSIONS: Present results suggested a gender related differences in anatomic features of incisive canal and surrounding buccal bone. In addition, crestal canal diameter, buccal bone length, and thickness parameters might be different in distinct countries.

Inpatient evaluation of periodontal, esthetic and inflammatory parameters around dental implants and natural teeth.

AIM: The use of endosseous dental implants (DI) has become a successful treatment alternative. However, providing periimplant tissue health and achieving a natural esthetic look are important topics in this treatment. The aim of the present study was to evaluate periodontal and esthetic parameters around DI and natural teeth (NT) and also to analyze myeloperoxidase (MPO) levels in gingival crevicular fluid (GCF) and peri-implant sulcus fluid (PISF). MATERIALS AND METHODS: Twenty DI supported fixed prosthesis and contralateral 20 NT were enrolled to the present study. Clinical periodontal parameters (probing depth, clinical attachment level, gingival bleeding time index and gingival index) were recorded and GCF/PISF samples were obtained from mesial (mesiobuccal and mesiolingual) and distal (distobuccal and distolingual) sites of DI and NT. MPO levels were spectrophotometrically determined. Additionally clinical photographs were obtained and esthetical evaluations were performed by using Jemt papilla index. The parameters belong to DI and NT were compared and correlations were evaluated using statistical analysis. RESULTS: A total of 40 samples were evaluated. No statistically significant differences were detected between groups in all periodontal parameters and MPO levels from mesial and distal sites. Jemt papilla index scores were slightly higher in NT however, this difference was not statistically significant (p > 0.05). Total PES score were similiar in DI and NT groups. Significant correlations were detected between MPO and gingival index values as expected. CONCLUSION: These results suggest that DI and NT have similar inflammatory conditions and esthetics, representing DI as a predictable treatment option. CLINICAL SIGNIFICANCE: Dental implants are satisfactory treatments, they provide patient esthetic natural looking, phonetic and masticatory functions.

Are marginal bone levels and implant stability/mobility affected by single-stage platform switched dental implants? A comparative clinical study.

OBJECTIVES: The aim of this study was to evaluate short-term bone level and stability/mobility measurement alterations at platform switched (PS) and standard platform (SP) implants placed in mandibular premolar/molar regions using a single-stage protocol. MATERIALS AND METHODS: Sixteen PS and 16 SP implants restorated with fixed prosthesis were included. Standard implant dimensions were used for both implant systems. After 3 months of osseointegration, implants were connected to abutments and final restorations were performed. Marginal bone loss was measured by standardized periapical radiographs. Implant stability/mobility was determined by resonance frequency analysis (RFA) and mobility measuring (MM) device values. Peri-implant parameters were evaluated with clinical periodontal indices and all parameters were assessed at baseline, 1, 3, and 6 months after the surgery. RESULTS: After 6 months, all implants showed uneventful healing. Radiographic evaluation showed a mean bone loss of 0.72 mm for PS and 0.56 mm for SP implants, and there were no significant differences between implant types. At 6 months, mean implant stability quotient (ISQ) values were 73.38 and 77 for PS and SP implants, respectively. Mean MM values were -4.75 for PS and -6.38 for SP implants. Mean MM values were lower for SP implants compared to PS implants at all time points. No significant differences were detected between implant types according to clinical peri-implant parameters. CONCLUSIONS: The micro-gap at crestal level which immediately exposed to the oral cavity in non-submerged two part implants seems to have adverse influence on the marginal bone level.

Primary stability/mobility of 1-stage and 2-stage dental implants: a comparative in vitro study.

PURPOSE: To evaluate the primary stability of 1-stage (nonsubmerged) and 2-stage (submerged) implants via newest wireless resonance frequency (RF) analyzer and newer wireless mobility measuring (MM) device. MATERIALS AND METHODS: Six 1-stage dental implants with internal hex connection and six 2-stage dental implants, 4.1 mm in diameter and 11.5 mm in length, were inserted bilaterally into the first premolar, second premolar, and first molar regions of 6 standard mandibular transparent self-curing acrylic resin models. After that, the periimplant circular bone defects were created in millimeter increments ranging between 0 and 5 mm to the same extent on all implants. RESULTS: Implant stability quotient values significantly decreased at 1-stage and 2-stage implants when periimplant defects increased. Similar implant stability quotient values were found for both implant types; however, significantly lower MM values were noted for 2-stage implants. Irrespective of implant systems, the results indicated a significant association between wireless RF analyzer and wireless MM device. CONCLUSION: Both wireless RF analyzer and wireless MM device were adequate in assessing implant stability. There was no difference between 2-stage and 1-stage implant systems, except lower MM values were noted for nonsubmerged implants.

Inferior alveolar nerve topography and its bifurcation features: a cone beam computed tomography evaluation.

BACKGROUND: Mandibular canal (MC) is the most important vital structure in mandible to prevent from complications such as bleeding and paresthesia. The aims of the present study were to inform the features (diameter, distances to the mandibular borders, and distance to tooth apex) of the MC for each posterior tooth region, and to present the bifurcation features of the MC. METHODS: Four-hundreds-eighteen MC images of 209 patients were evaluated. The parameters were recorded from right and left hemi-mandibles for each posterior teeth region: 1) MC diameter; 2) MC and mandibular basis distance; 3) MC and crest distance; 4) MC and tooth apex distance; 5) MC and buccal plate distance; 6) MC and lingual plate distance; and 7) possible implant length (the distance between 2 mm coronal of the MC and 1 mm apical of the crest). Additionally, MC bifurcation type and bifid mandibular canal length were noted for right and left sides. RESULTS: While higher MC diameter values were recorded at molars, MC diameter in first premolars bilaterally were the lowest. In premolars, MC and mandibular basis distance showed higher values than molars. There was a trend of decrease in MC and crest distance from molars to premolars. The highest MC and tooth apex distance was measured in second molar; however, the lowest was in the first premolar. Additionally, MC and buccal plate distances were higher in molars, while MC and lingual plate distances were higher in premolars. Possible implant length in first premolar was the lowest, when it was the highest in second molars. CONCLUSIONS: For simulating overall MC topography, it extended bucco-coronally from molars to premolars. Due to this topography, possible implant length increased from premolars to molars.