Evaluation of hemodynamic changes and patient-reported outcome measures in surgical therapy with or without intravenous sedation: a prospective controlled clinical study.

OBJECTIVES: To determine whether intravenous (IV) sedation would contribute to the stabilization of patients' hemodynamics during periodontal and oral surgical procedures, and to evaluate the patient-reported outcome measures (PROMs). MATERIALS AND METHODS: Periodontal or oral surgery patients were recruited and distributed into two groups: (1) sedation group (SG): intravenous sedation plus local anesthesia; (2) control group (CG): local anesthesia only. Systolic and diastolic blood pressure (SBP, DBP), heart rate (HR), and oxygen saturation (SaO2), were monitored at 15-min intervals from sitting in the dental chair (baseline) until the end of the treatment. In addition, a subjective assessment of PROMs was obtained through a post-operative questionnaire. RESULTS: Forty-nine patients (25 in SG and 24 in CG) were included. The highest SBP and DBP were significantly higher in CG compared to the SG (141.1 ± 18.4 and 133.6 ± 15.1, respectively in SBP; and 85.5 ± 11.0 and 82.9 ± 10.1, respectively in DBP), but no mean significant differences were found between groups (P value of 0.85 and 0.72 for systolic and diastolic BP, respectively). HR and SaO2 did not show statistical intra- and inter-group differences. The overall patient satisfaction score was significantly higher in the SG group compared to CG. CONCLUSIONS: Intravenous moderate sedation seems to contribute to the stabilization of patient's hemodynamics, especially the systolic blood pressure, although small differences have been found. CLINICAL RELEVANCE: Intravenous sedation seems to contribute to stabilize the hemodynamic values, and enhances the patient satisfaction after periodontal and oral surgical treatment in the dental office.

Accuracy of static fully guided implant placement in the posterior area of partially edentulous jaws: a cohort prospective study.

OBJECTIVE: A cohort prospective study was conducted to assess the three-dimensional positioning accuracy of the implant between pre-surgical and the final implant position using a static fully guided approach in the posterior area of the jaws. MATERIALS AND METHODS: A total of 60 implants (30 patients) were digitally analyzed after superimposing the Digital Imaging and Communications in Medicine (DICOM) files obtained from the Cone Beam Computed Tomography (CBCT) pre- and post-implant placement. The software calculations included deviations at the implant shoulder and at the implant apex, global deviation (3D offset), and angle deviation. Statistical analysis was performed with α = 0.05. RESULTS: Considering the total number of implants, mesiodistal, buccolingual, and apicocoronal mean deviations at the shoulder and implant apex were equal or below 0.21 ± 0.69 mm, and only the buccolingual mean deviation at the apex reached up to 0.67 ± 1.06 mm. The mesiodistal and apicocoronal deviations were not statistically significant at both the shoulder and apex levels of the implant. The mean total angular deviation was 5.62° ± 4.09. The main limitation of this surgical approach was the requirement for a wide mouth opening. CONCLUSIONS: Static fully guided surgery for dental implant placement exhibits minimum deviations respect to presurgical planning. The main limitation in the posterior areas is the requirement for a wide mouth opening. CLINICAL RELEVANCE: Even with minimum deviations clinically acceptable, precautions and safety margins must be respected when using static full-guided surgery to place dental implants.

Accuracy of dynamic implant navigation surgery performed by a novice operator.

AIM: The main objective was to evaluate the accuracy of dynamic navigation-guided surgery (DNGS) for implant positioning performed by a novice operator. The secondary objectives were to analyze the operator's learning curve and identify possible complications deriving from the technique. MATERIALS AND METHODS: Twenty-five implants were placed in eight partially edentulous human heads. Preoperative CBCT scans were imported to planning software to determine the implant positions. Implants were placed using a dynamic navigation system. Postoperative CBCTs were superimposed onto the implant planning images. Discrepancies between the virtually planned implant positions and the postoperative positions were evaluated by measuring horizontal platform deviation, apex deviation, apicocoronal (vertical) deviation, and angular deviation. RESULTS: Mean platform, apex, vertical, and angle deviations were 1.55 ± 0.81 mm, 2.45 ± 0.84 mm, 1.59 ± 0.70 mm, and 5.56 ± 4.03 degrees, respectively. No significant differences were found between the maxilla and mandible or between anterior and posterior sites. A flat learning curve was observed, with the exception of the implant platform, where a tendency toward improvement in accuracy was observed between the 8th and the 17th implant placed. No complications were reported. CONCLUSIONS: Based on the results of a study performed by a novice operator on a cadaveric model, DNGS allows accurate implant placement within a 2-mm safety margin in terms of implant platform and vertical positions, and a 3-mm margin in apical vicinities. The technique requires practice to learn the required eye-hand coordination. (Int J Comput Dent 2022;25(4):377-0; doi: 10.3290/j.ijcd.b2588207).

Intra-osseous heat generation during implant bed preparation with static navigation: Multi-factor in vitro study.

OBJECTIVES: To compare the intra-osseous temperature reached during bone drilling for dental implant placement using open versus closed static surgical guides and evaluate the influence of bone density, osteotomy drilling depth, and irrigation fluid temperature. MATERIAL AND METHODS: 960 osteotomies were performed with 2 mm pilot drills in 16 solid rigid polyurethane foam blocks. Two main variables were considered: the guide type (open or closed guide) and bone density (hard (D1) or soft (D4). The blocks were divided into four groups according to the type of surgical template and bone density as follows: group one: closed guide and hard bone; group two: open guide and hard bone; group three: closed guide and soft bone; and group four: open guide and soft bone. A combination of different experimental conditions was used, including different bone osteotomy depths (6 or 13 mm) and irrigation fluid temperatures (5°C or 21°C). RESULTS: The highest mean temperature was found in group one (28.29 ± 4.02°C). In the soft bone groups (three and four), the mean maximum temperature decreased compared to groups one and two (dense bone) and was always higher with closed guides (23.38 ± 1.92°C) compared to open guides (21.97 ± 1.22°C) (p < .001). The osteotomy depth and irrigation fluid temperature also significantly influenced the bone temperature (p < .001), especially in hard bone. CONCLUSIONS: The greatest heat generation was observed in high-density bone. The final intra-bone temperature was about 1°C higher with a closed static surgical guide than with an open guide. The heat generation in osteotomy sites was substantially reduced by cooling the irrigation fluid to 5°C.

Influence of bone density, drill diameter, drilling speed, and irrigation on temperature changes during implant osteotomies: an in vitro study.

OBJECTIVE: The aim of this in vitro study was to evaluate the influence of bone type, drill diameter, drilling speed, and irrigation on heat generation while performing osteotomy for dental implants. MATERIALS AND METHODS: Six polyurethane foam blocks simulating type I (dense) and type IV (soft) bone were selected for the study. Each block was subjected to two different experimental conditions for each drill (2- and 3.5-mm diameter): three sub-groups were created: (a) revolutions per minute (50, 100, or 800 rpm) and (b) irrigation (with or without irrigation). RESULTS: In 2-mm drill group, maximum temperature attained was practically identical: 23.73 ± 2.28 °C in the cortical bone and 23.74 ± 2.03 °C in the cancellous bone. For 3.5-mm, groups showed similar results (25.01 ± 1.88 °C for cortical and 24.05 ± 1.94 °C for trabecular bone). In any type of bone, the presence of irrigating fluid helped to control the maximum temperature (p = 0.001). When comparing the 2-mm and 3.5-mm drills, most differences were found at 100 rpm without irrigation (p < 0.001) and at 800 rpm with irrigation (p = 0.001). CONCLUSIONS: Maximum temperature attained was always below the critical threshold that can cause osteonecrosis, showing that both external irrigation with higher drilling speeds and no irrigation with lower speeds were effective methods to avoid excessive heat generation. CLINICAL RELEVANCE: Despite being always below the critical temperature, bone type, drill diameter, drilling speed, and irrigation must be considered temperature-influencing factors during implant osteotomies.

Meta-analysis of randomized clinical trials comparing clinical and patient-reported outcomes between extra-short (≤6 mm) and longer (≥10 mm) implants.

AIM: To compare the clinical outcomes of ≤6 mm extra-short implants (test group) versus ≥10 mm long implants (control group), with and without bone augmentation procedures. MATERIALS AND METHODS: A systemic literature search of randomized clinical trials was performed using the PubMed (MEDLINE) and EMBASE databases. A quantitative meta-analysis was conducted to compare all the outcome variables. Meta-regression analysis determined the effect of bone augmentation procedures and the influence of other clinical covariates on the results. RESULTS: Eighteen studies comprising 1,612 implants (793 extra-short and 820 long implants) were selected for the meta-analysis. No statistically significant difference in the survival rate was observed at 1 and 3 years (p > 0.05). Extra-short implants displayed less marginal bone loss (MBL) from both implant placement time points (1 and 3 years) and prosthetic placement (1 year), as well as less biological complications, surgical time and treatment cost (p < 0.05). Contrarily, a statistically significant small number of prosthetic complications were reported with long implants (p < 0.05). CONCLUSIONS: Placement of extra-short implants (≤6 mm) presented as an equivalent option in the treatment of patients with an atrophic posterior arch up to 3-year follow-up. However, the long-term effectiveness of extra-short dental implants remains to be further studied.

Schneiderian membrane perforation via transcrestal sinus floor elevation: A randomized ex vivo study with endoscopic validation.

OBJECTIVE: To endoscopically determine the incidence of Schneiderian membrane perforation during transcrestal maxillary sinus floor elevation (SFE), in relation to the bone preparation technique, amount of bone graft, membrane elevation height and different surgical steps. MATERIALS AND METHODS: Seven cadaver heads corresponding to 12 maxillary sinuses were used to perform three SFE via transcrestal approach per sinus (36 elevations). Each sinus was randomly assigned to either the Sinus Crestal Approach (SCA) drill kit technique (experimental group) or the conventional osteotome technique (control group). During all phases of the surgery, the integrity of the sinus membrane was monitored through endoscopic examination. RESULTS: A significant difference was found in the incidence of perforation (p = 0.007) and vertical elevation height (p < 0.001) between the study groups, favoring the experimental group. A safety elevation threshold of 5 mm without bone graft and implant placement was estimated. A significant correlation was observed between the residual ridge height and the incidence of perforation (p < 0.001; OR = 0.51). CONCLUSION: The SCA drill kit may demonstrate superior osteotomy preparation and membrane elevation capabilities to the osteotome technique, and significantly when a 6-mm SFE is indicated. Residual ridge height and vertical elevation height are risk determinant factors.

Microscope and micro-camera assessment of Schneiderian membrane perforation via transcrestal sinus floor elevation: A randomized ex vivo study.

OBJECTIVE: We sought to assess the effectiveness of using a microscope and non-invasive camera for assessing sinus membrane perforations during transcrestal sinus floor elevation (TSFE). MATERIALS AND METHODS: Five fresh human cadaver heads corresponding to eight maxillary sinuses (six bilateral and two unilateral) underwent 4 TSFEs per sinus (a total of 32 single site elevations). Each elevation was randomly assigned to receive a three or six mm membrane elevation height (MEH). A microscope and micro-camera were used to assess the sinus membrane perforation. Afterwards, radiological and clinical membrane perforation assessments were performed. The statistical analysis results are expressed using the means, standard deviations, range values of the residual ridge height (RRH), residual ridge width (RRW), sinus membrane thickness (SMT) and incidence of perforation (IoP). Generalized linear methods were used to test for the correlation of RRH and MEH to the microscope and micro-camera perforation assessments and the correlation of microscope and micro-camera assessments with the post-operative CBCT and crestal liquid evaluation. RESULTS: The cumulative percentage of IoP was 40.62%, (23.07% with 3 mm MEH, and 76.92% with 6 mm MEH, p < 0.05). The perforation assessed using either the microscope or micro-camera coincided with the post-operative CBCT and crestal liquid assessment in 87.55% sites. No significant correlation was found between the microscope or micro-camera assessments with RRH or MEH. CONCLUSION: Application of a microscope and micro-camera during transcrestal sinus floor elevation may allow the detection of the integrity of the Schneiderian membrane with greater than 85% accuracy in this ex vivo model.

Correction to: Influence of surface treatment on osseointegration of dental implants: histological, histomorphometric and radiological analysis in vivo.

Dear Professor Dr. Matthias Hannig. Editor-in-Chief Clinical Oral Investigations. Following the publication of our paper by Calvo Guirado et al, 2015 [1] in Clinical Oral Investigations, it came to light that a certain part of the text at the materials and methods and results sections were similar.

Influence of Implant Position in Implant-Assisted Removable Partial Denture: A Three-Dimensional Finite Element Analysis.

PURPOSE: To determine the ideal position of a dental implant to assist a posterior extended partial removable dental prosthesis (PRDP), through stress values, displacement values, and deformation of periodontal ligament (PDL). MATERIALS AND METHODS: A finite element analysis of different implant positions was analyzed using a 3D mandible model from a human patient. Test models were created: model A (implant in second molar area), model B (implant in the first molar area), and model C (implant in premolar area). A control model without implant support was also created. Overall displacement values, von Mises stress distribution maps, and nonlinear deformations were evaluated. RESULTS: Some differences could be observed between test models. The introduction of an implant in the edentulous area, unlike a conventional removable partial denture without implant support, decreases stress values in the biological structures such as: mandible, tooth, soft tissue, and PDL. Placing the implant in the first molar area resulted in improved displacement values, and reduced maximum stress values at the peri-implant bone area, metal structure, and implant were observed. CONCLUSIONS: Within the limitations of this study we can conclude that placing the implant in the position of the first molar improves biomechanical behavior of implant-assisted PRDPs.

Conditioned medium from fresh and demineralized bone enhances osteoclastogenesis in murine bone marrow cultures.

OBJECTIVES: Osteoclasts rapidly form on the surface of bone chips at augmentation sites. The underlying molecular mechanism, however, is unclear. Soluble factors released from bone chips in vitro have a robust impact on mesenchymal cell differentiation. Whether these soluble factors change the differentiation of hematopoietic cells into osteoclasts remains unknown. METHODS: Osteoclastogenesis, the formation of tartrate-resistant acid phosphatase-positive multinucleated cells, was studied with murine bone marrow cultures exposed to RANKL and M-CSF, and conditioned medium from fresh (BCM) and demineralized bone matrix (DCM). Histochemical staining, gene and protein expression, as well as viability assays were performed. RESULTS: This study shows that BCM had no impact on osteoclastogenesis. However, when BCM was heated to 85°C (BCMh), the number of tartrate-resistant acid phosphatase-positive multinucleated cells that developed in the presence of RANKL and M-CSF approximately doubled. In line with the histochemical observations, there was a trend that BCMh increased expression of osteoclast marker genes, in particular the transcription factor c-fos. The expression of c-fos was significantly reduced by the TGF-ß receptor I antagonist SB431542. DCM significantly stimulated osteoclastogenesis, independent of thermal processing. CONCLUSIONS: These data demonstrate that activated BCM by heat and DBM are able to stimulate osteoclastogenesis in vitro. These in vitro results support the notion that the resorption of autografts may be supported by as yet less defined paracrine mechanisms.

Topical applications of vitamin D on implant surface for bone-to-implant contact enhance: a pilot study in dogs part II.

OBJECTIVE: The aim of this study was to evaluate the effect of topical application of vitamin D over implant surface, placed immediately to the extraction, throughout histological and histomorphometric analysis of peri-implant tissue. MATERIAL AND METHODS: Six American foxhound dogs were used in the study. Mandibular premolar distal roots were extracted. Twenty-four immediate conical C1 implants (MIS, Barlev, Israel) were randomly assigned to the distal site on each site of the mandible in three groups: (Group CI) 12 titanium implants alone; (Test Group DI) 12 titanium implants supplemented with vitamin D. Prior to implanting, test implants (DI) were submerged in vitamin D 10% solution. No treatment was applied at control implants (CI). After 12 weeks, animals were sacrificed. Block sections were obtained and processed for mineralized ground sectioning. Bone-to-implant contact (Total BIC and BIC%), new bone formation (NBF), interthread bone (ITB), and histological linear measurements (HLM) were analyzed. RESULTS: At 12 weeks, all implants were clinically stable and histologically osseointegrated. BIC evaluation showed Total BIC mean and SD values for DI (48.96 ± 2.14), CI (44.56 ± 1.75) (P < 0.05), BIC% DI (43.59 ± 0.98), and CI (42.67 ± 9.26) (P > 0.05). For interthread bone formation, values were as follows: DI (15.21 ± 3.87), CI (14.79 ± 1.45) (P > 0.05), no statistically differences. Regarding peri-implant new bone formation, no statistically differences could be found between the two groups DI (31.87 ± 1.23), CI (27.18 ± 2.38) (P > 0.05). For linear measurements, test group (DI) showed statistically significant less buccal crestal bone loss (CBL) DI (0.37 ± 0.12)*, CI (1.26 ± 0.8) (P < 0.05), and vitamin D implants showed less lingual junctional epithelium DI (1.58 ± 0.43)*, CI (2.18 ± 0.48) (P < 0.05). No differences were observed in the buccal mucosa. CONCLUSION: With the limitation of animal studies, topical application of vitamin D on dental implants could reduce crestal bone loss and increase 10% more bone-to-implant contact at 12-week follow-up period.

Xenografts Supplemented with Pamindronate placed in postextraction sockets to avoid crestal bone resorption. Experimental study in Fox hound dogs.

OBJECTIVES: The aim of the study was to compare the effects of porcine xenografts (MP3(®)) with or without pamindronate for the healing of small and large defects of postextraction sockets. MATERIALS AND METHODS: Six beagle dogs were used in the study; second premolars and first molars of the mandible were extracted, small defects (SD) and large defects (LD) were identified. Each defect was measured and randomly filled as follows: SC (small control defects filled with MP3(®) alone), ST (small test defects filled with MP3(®) modified with pamindronate), LC (large control defects filled with MP3(®) alone), LT (large test defects filled with MP3(®) modified with pamindronate). After 4 and 8 weeks, the animals were euthanized and the percentages of new bone formation (NB), residual graft (RG) and connective tissue (CT) were analysed by histology and histomorphometry of undecalcified samples. RESULTS: After 4 weeks, NB formation was higher for ST compared to all groups and for LT compared to LC (P < 0.05); RG was significantly higher in both control groups compared to tests (P < 0.05); and CT was higher in large defects (LC and LT) compared to small defects. After 8 weeks, NB formation was higher for test groups (ST and LT) compared to controls (P < 0.05); RG was significantly higher in both control groups compared to tests (P < 0.05); and CT was higher in large defects (LC and LT) compared to small defects (P < 0.05). CONCLUSIONS: Within the limitations of this experimental study, the findings suggest that porcine xenografts modified with pamindronate favours the new bone formation and increased the porcine xenograft substitution/replacement after 4 and 8 weeks of healing.

Effect of implant macro-design on primary stability: A prospective clinical study.

BACKGROUND: Implant restorations have become a high predictable treatment option. Several caracteristics such as surgical technique and implant design can influence the treatment outcomes. The aim of the present study was to evaluate the influence of implant macro-design on primary stability measured with resonance frequency analysis (RFA) and insertion torque (IT). Material and Mehods: A total of 47 implants divided in two groups: Test group (TI): 22 Tapered MIS® Seven implants; Control group (CI): 25 cylindrical Astra® Osseospeed implants. All implants were inserted following the manufacturers' standard protocols. Implant primary stability was measured at the moment of implant placement by registering insertion torque values (ITv) and ISQ values by means of Osstell™ Mentor (ISQv) (Integration Diagnostic Ltd., Goteborg, Sweden). RESULTS: In the mandible, mean ISQv for tapered implants (TI) was 71.67±5.16 and for cylindrical implants (CI) 57.15±4.83 (p=0.01). Mean insertion torque was 46.67±6.85 Ncm for TI and 35.77±6.72 Ncm for CI (p=0.01). In the maxilla, mean ISQ was 67.2±4.42 for tapered implants and 49.17±15.30 for cylindrical implants (p=0.01). Mean insertion torque for TI was 41.5±6.26 Ncm and for CI 39.17±6.34 Ncm (p>0.05). For tapered implants, no correlation could be found between implant diameter and primary stability. But for cylindrical implants there was a statistically significant correlation between implant diameter and primary stability: ITv (p=0.03); ISQv (p=0.04). CONCLUSIONS: Within the limits of the present study, tapered shaped implants achieve higher primary stability measured through ISQ and insertion torque values. Moreover, for cylindrical implants positive correlation has been established between implant diameter and primary stability.

Zirconia with laser-modified microgrooved surface vs. titanium implants covered with melatonin stimulates bone formation. Experimental study in tibia rabbits.

OBJECTIVES: The aim of the study was to evaluate if zirconia implants with micro-grooved surfaces supplemented with melatonin enhance the bone-to-implant contact (BIC) vs. titanium implants with the same coating. MATERIALS AND METHODS: Eighty implants divided in four groups were inserted in the tibia of 20 New Zealand rabbits as follows: (group A) 20 titanium implants; (group B) 20 micro-grooved zirconia implants; (group C) 20 titanium implants supplemented with melatonin and (group D) 20 micro-grooved zirconia implants supplemented with melatonin. Histometric and SEM evaluation of BIC were evaluated after 1 and 4 weeks. RESULTS: At 1 week, group C (29.7 ± 2.4%) and group D (28.9 ± 1.3%) implants showed higher BIC% compared with group A and B (P < 0.05). After 4 weeks, group D showed higher BIC compared with all the groups (47.5 ± 2.2%) (P < 0.05). Also Connective tissue was higher in groups B (78.9 ± 2.1%) and D (88.7 ± 1.2%) related to titanium and zirconia melatonin untreated at 4 weeks (P < 0.05). CONCLUSIONS: Within the limitations of this pilot study in rabbits, we can conclude that the local application of melatonin increases the BIC values in titanium and in zirconia implants at 1 week.

Influence of surface treatment on osseointegration of dental implants: histological, histomorphometric and radiological analysis in vivo.

OBJECTIVE: The aim of this article is to compare the influence of surface treatment on the integration (at 2, 4 and 8 weeks) of 120 dental implants inserted in 60 tibiae of rabbits. MATERIALS AND METHODS: Four different surfaces were double-blind tested: blasted, acid-etched and discrete crystal deposition (DCD) (group A); blasted (group B); acid-etched (group C) and blasted and acid-etched (group D). Bone-to-implant contact plus reverse torque and bone level were measured at the time of implant insertion and at 14, 28 and 56 days of healing. RESULTS: Group A showed the highest early and late bone-to-implant contact (BIC) values: 40.8 ± 2.3 % at 14 days decreasing to 27.7 ± 1.1 % after 28 days and 39.4 ± 1.4 % at 56 days. For group B, the average BIC values at 14, 28 and 56 days were 23.34 ± 2.1, 23.77 ± 1.9 and 29.47 ± 1.7 %, respectively. Group C showed a value of 25.72 ± 2.3 % after 14 days of integration, 34.92 ± 2.2 % at 28 days and 32.91 ± 1.6 % at 56 days. Group D showed a BIC value of 32 ± 2.5 % at 14 days, 32.85 ± 1.4 % at 28 days and 34.04 ± 2.3 % at 56 days. In the scanning electron microscopy (SEM) analysis, no statistically significant differences were found. The Ca/P ratio values were 1.762 for surface A, 1.625 for surface B, 1.663 for surface C and finally 1.722 for surface D. CONCLUSIONS: Therefore, we conclude that even if there seems to be a tendency to obtain better BIC results with surface A (blasted-etched and covered with hydroxyapatite (HA)), no statistical differences were obtained in this study. CLINICAL RELEVANCE: The study shows the influence of different implant surfaces in increasing osseointegation for immediate loading implants.

Crestal bone loss related to immediate implants in crestal and subcrestal position: a pilot study in dogs.

OBJECTIVES: The aim of the present study was to compare crestal bone loss with different implant designs inserted immediately in crestal or subcrestal position in post-extraction sockets in a dog model. MATERIALS AND METHODS: The mandibular second, third, fourth premolars, and the first molars of six adult fox hound dogs were extracted bilaterally, and 48 implants were placed immediately in both hemi-arches of each dog. Randomly, eight implants (sky classic (®) and blue sky (®) ) were inserted, four crestally (control group) and four 2 mm subcrestally (test group). Both groups were treated with a minimal mucoperiosteal flap elevation approach. After a 12-week healing period, the animals were sacrificed, and samples were obtained. Biopsies were processed for ground sectioning. Histomorphometric analysis was carried out to compare buccal and lingual bone height loss. RESULTS: All implants were clinically and histologically osseointegrated. Healing patterns examined microscopically at eight and 12 weeks for both groups (crestal and subcrestal) yielded similar qualitative bone findings. At 12 weeks, the distance from the top of the implant collar to the first BIC (ISBc) showed significant difference between implant positions (crestal or subcrestal) in the buccal aspect (P = 0.1253), values for the crestal group being higher (1.79 ± 0.3 mm) in comparison with the subcrestal group (0.89 ± 0.5 mm). Better results were achieved by both implant designs when implants were placed in the deeper position. No significant differences were found in BIC values (P > 0.05). The total BIC at 8 weeks was (46.22 ± 4.29%) for the crestal group and (49.72 ± 2.21%) for the subcrestal group; at 12 weeks, it was (41.54 ± 3.87%) for the crestal group and (56.87 ± 3.46%) for the subcrestal group. CONCLUSIONS: Within the limitations of this study, the findings suggest that apical positioning of the top of the implant does not jeopardize bone crest and peri-implant tissue remodeling. However, less resorption of the lingual and buccal crest may be expected when implants are placed 2 mm subcrestally, but this is not related to implant design. Moreover, implants placed subcrestally produced better bone-to-implant contact measurements.

Comparison of hemodynamic changes with general or local anesthesia during dental treatment in pediatric patients: A prospective clinical study.

BACKGROUND AND AIM: Severe hemodynamic fluctuations during dental treatment can trigger highly undesirable physical reactions. A study was made to determine whether the administration of propofol and sevoflurane contributes to the stabilization of hemodynamic parameters during dental treatment in pediatric patients versus the use of local anesthesia alone. MATERIALS AND METHODS: Forty pediatric patients needing dental treatment were assigned to either general anesthesia with local anesthesia (study group [SG]) or local anesthesia alone (control group [CG]). Two percent sevoflurane in oxygen (100% oxygen, 5 L/min) and continuous propofol infusion (target-controlled infusion [TCI], 2 µg/mL) were used as general anesthesia agents in SG; and 2% lidocaine with 1:80,000 adrenaline was used as local anesthesia in both groups. Heart rate, blood pressure and oxygen saturation were measured before starting dental treatment (baseline) and every 10 min during dental treatment. RESULTS: Blood pressure (p < .001), heart rate (p = .021) and oxygen saturation (p = .007) decreased substantially after the administration of general anesthesia. The levels of these parameters subsequently remained low and then recovered at the end of the procedure. On the other hand, the oxygen saturation values remained closer to baseline in SG versus CG. In contrast, the hemodynamic parameters experienced lesser fluctuations in CG than in SG. CONCLUSIONS: General anesthesia affords more favorable cardiovascular parameters during the entire dental treatment in comparison to local anesthesia alone (blood pressure and heart rate decrease significantly and oxygen saturation proves more stable and with values closer to baseline), and allows dental treatment to be performed on healthy, lacking cooperative ability children who otherwise could not be treated with local anesthesia alone. No side effects were observed in either group.