Hemorrhagic Complications in Implant Surgery: A Scoping Review on Etiology, Prevention, and Management.

This article seeks to provide the most relevant aspects of the etiology, prevention, and management of bleeding in routine implant surgery. A comprehensive and systematic electronic search was conducted in MEDLINE, EMBASE, the Cochrane Central Register of Controlled Trials, and the Cochrane Database of Systematic Reviews databases until June 2021. Further references of interest were retrieved from bibliographic lists of the selected articles and the "Related Articles" feature of PubMed. Eligibility criteria were papers about bleeding, hemorrhage, or hematoma associated with routine implant surgery on human subjects. Twenty reviews and 41 case reports fulfilled eligibility criteria and were included in the scoping review. Involved implants were mandibular in 37 and maxillary in 4 cases. The major number of bleeding complications was in the mandibular canine region. The most injured vessels were sublingual and submental arteries, due mainly to perforation of the lingual cortical plate. Time to bleeding occurred intraoperatively, at suturing, or postoperatively. The most reported clinical manifestations were swelling and elevation of the mouth floor and the tongue with partial or complete airway obstructions. First aid to manage airway obstruction was intubation and tracheostomy. For active bleeding control, gauze tamponade, manual or digital compression, hemostatic agents, and cauterization were applied. When conservative procedures failed, hemorrhage was controlled by intra- or extraoral surgical approaches to ligate injured vessels or by angiographic embolization. The present scoping review provides knowledge and evidence on the most relevant aspects of the etiology, prevention, and management of implant surgery bleeding complications.

Effects of an amino acid buffered hypochlorite solution as an adjunctive to air-powder abrasion in open-flap surface decontamination of implants failed for peri-implantitis: an ex vivo randomized clinical trial.

OBJECTIVES: To evaluate ex vivo the efficacy of an amino acid buffered hypochlorite solution supplemented to surface debridement with air-powder abrasion in removing bacterial biofilm following open-flap decontamination of implants failed due to peri-implantitis. MATERIALS AND METHODS: This study was an ex vivo, single-blind, randomized, intra-subject investigation. Study population consisted of 20 subjects with at least three implants failed for peri-implantitis (in function for > 12 months and progressive bone loss exceeding 50%) to be explanted. For each patient, implants were randomly assigned to surface decontamination with sodium bicarbonate air-powder abrasion (test-group 1) or sodium bicarbonate air-powder abrasion supplemented by amino acid buffered hypochlorite solution (test-group 2) or untreated control group. Following open-flap surgery, untreated implants (control group) were explanted. Afterwards, test implants were decontaminated according to allocation and explanted. Microbiological analysis was expressed in colony-forming units (CFU/ml). RESULTS: A statistically significant difference in the concentrations of CFU/ml was found between implants of test-group 1 (63,018.18 ± 228,599.36) (p = 0.007) and implants of test-group 2 (260.00 ± 375.80) (p < 0.001) compared to untreated implants (control group) (86,846.15 ± 266,689.44). The concentration of CFU/ml on implant surfaces was lower in test-group 2 than in test-group 1, with a statistically significant difference (p < 0.001). CONCLUSION: The additional application of amino acid buffered hypochlorite solution seemed to improve the effectiveness of implant surface decontamination with air-powder abrasion following open-flap surgery. CLINICAL RELEVANCE: Lacking evidence on the most effective method for biofilm removal from contaminated implant surfaces, the present experimental study provides further information for clinicians and researchers.

Immediate flapless full-arch rehabilitation of edentulous jaws on 4 or 6 implants according to the prosthetic-driven planning and guided implant surgery: A retrospective study on clinical and radiographic outcomes up to 10 years of follow-up.

OBJECTIVES: to retrospectively evaluate clinical and radiographic outcomes of immediate, flapless full-arch prostheses, supported by 4/6 implants according to prosthetic-driven planning and guided surgery. MATERIALS AND METHODS: The study involved 28 edentulous patients (20 female/8 males; average age 67.75 ± 8.627 years), 32 prostheses (17 all-on-4/15 all-on-6) and 164 implants. The Implants survival, prostheses success/survival, peri-implant marginal bone loss, incidence of biological and prosthetic complications were evaluated. Multiple linear regression analysis was performed to analyze the influence of implant and patient characteristics on marginal bone loss. RESULTS: Cumulative implant survival rate was 89.7% for all-on-four (seven failures) and 99.0% for all-on-six (one failure) after a mean follow-up of 6.46 ± 2.236 years (range 1-10 years). Cumulative prosthesis success rate was 51.5% (58.8% for all-on-four/ 43.8% for all-on-six). Prosthesis survival rate was 88.2% for all-on-four. No failure was registered in all-on-six. Mean value of marginal bone loss was 1.38 ± 0.1.28 mm at 5-year and 2.09 ± 0.56 mm at 10-year follow-up. No difference was found in the mean value of marginal bone resorption between all-on-four (1.56 ± 1.61 mm) and all-on-six (1.20 ± 0.85 mm) (p = 0.104) and between tilted (1.22 ± 1.29 mm) and axial implants (1.44 ± 1.27 mm) (p = 0.385) after 5-year follow-up. The incidence of biological complications was 1.0% in all-on-six (one mucositis) and 10.3% in all-on-four (two peri-implantitis). Prosthetic complications affected teeth of final rehabilitations with 3 detachments, 10 chippings or fractures, and 3 severe occlusal wears. CONCLUSIONS: Based on the results and within the limitations of the present study, the implant-supported hybrid prosthesis according to prosthetic-driven planning and guided surgery showed to be an efficient, safe, and effective approach to rehabilitate edentulous jaws.

Effects of ibuprofen administration timing on oral surgery pain: A randomized clinical trial.

OBJECTIVE: This study aimed to compare the analgesic effect of ibuprofen 400 mg given 30 min before or immediately after third molars surgery under local anaesthesia. MATERIALS AND METHODS: The single-centre, randomized, split-mouth, triple-blind, clinical trial involved 38 outpatients, for a total of 76 bilateral symmetrical fully bone impacted mandibular third molars. Each patient was undergone to separate surgical sessions for the right and left side, and ibuprofen was randomly administered 30 min before or immediately after the intervention. Study participants recorded pain intensity using Numerical Rating Scale-11, the timing of rescue therapy intake and overall tablets consumption over 3 days. RESULTS: The overall pain intensity score was lower in the group receiving ibuprofen immediately after (3.13 ± 2.46) than before (3.58 ± 2.40) surgery, with statistically significant differences only on the second and third days. The mean time to the first using rescue therapy was longer in the postoperative (598.33 ± 422.62 min) than in the preoperative (406.25 ± 149.79 min) analgesic treatment group (p = .123). The number of supplemented ibuprofen tablets did not differ (p = .530) between both groups. CONCLUSIONS: Within the limits of the present study, ibuprofen administration immediately after surgery seemed to be more effective than preoperative administration.

COMPARATIVE ANALGESIC EFFECTS OF SINGLE-DOSE PREOPERATIVE ADMINISTRATION OF PARACETAMOL (ACETAMINOPHEN) 500 mg PLUS CODEINE 30 mg AND IBUPROFEN 400 mg ON PAIN AFTER THIRD MOLAR SURGERY.

BACKGROUND: Efficacy and rapid onset of postsurgical oral pain relief are critical to improve clinical outcomes and reduce the risk of excessive dosing with analgesic drugs. PURPOSE: To compare analgesic effects of preoperative administration of paracetamol 500 mg plus codeine 30 mg in single-tablet and effervescent formulation to ibuprofen 400 mg, and placebo in the management of moderate to severe postoperative pain after mandibular third molar surgery. MATERIALS AND METHODS: One hundred twenty healthy outpatients aged 15-29 years undergoing surgical removal of 1 bony impacted mandibular third molar were enrolled in this, single-center, prospective, randomized, triple-blind parallel-group, placebo-controlled, clinical trial. Study participants were randomly assigned to three treatment arms. According to the concealed allocation, each patient 30 minutes before surgery received paracetamol 500 mg plus codeine 30 mg (group APAP/COD), ibuprofen 400 mg (group IBU) or placebo (group PLA). Rescue therapy allowed in the postoperative period was paracetamol 500 mg plus codeine 30 mg in groups APAP/COD and PLA and ibuprofen 400 mg in group IBU. Patients recorded on Numerical Rating Scale-11 (NRS-11) the pain intensity, total number of postoperative-supplement medications and time of the first intake, until 12-hours after surgery and over extra 2 days, RESULTS: Over postoperative 3 days, patients in the APAP/COD group (2.33 ± 1.99) displayed significantly (P< .001) less pain intensity than IBU (3.43 ± 2.47) and placebo (3.57 ± 2.62) groups. The first-day postoperative pain was significantly (P < .001) higher in group PLA than in groups APAP/COD and IBU, but not between the latter 2 groups. However, at 2 hours postdose, the IBU group displayed average pain intensity lower than APAP/COD group (P> .05). On the next 2 days, pain intensity was significantly (P< .001) lower in group APAP/COD than in groups IBU and PLA but failed to reach statistical significance between groups IBU and PLA. Although the time to the first using rescue therapy was longer (445.88 ± 159.96 minute) in group IBU, compared to groups APAP/COD (392.67 ± 138.90 minutes) and PLA (323.00 ± 143.95 minutes), the number of supplemented tablets was significantly higher in group IBU (2.89 ± 2.13) than in groups APAP/COD (1.24 ± 1.79) (P= .001) and PLA (1.53 ± 1.67) (P = .008). No adverse events were registered for all groups. CONCLUSIONS: Within the limits of the present study, over postoperative 3 days, a statistically significant intensity pain reduction and decreased rescue therapy consumption were recorded in the paracetamol-codeine group than to ibuprofen group. Nevertheless, lower pain intensity at 2 hours postdose and longer time using rescue therapy was found in the ibuprofen group without statistical significance. No adverse events occurred over the studied period.

First and second permanent molars with failed or delayed eruption: Clinical and statistical analyses.

INTRODUCTION: The aim of this work was to analyze data of patients with failed or delayed eruption of first and second permanent molars, to assess the effectiveness of the treatment methods used. METHODS: Epidemiologic and clinical data of 125 patients (mean age 14.08 ± 4.04 years) with 197 affected molars (30 first and 167 second molars) were retrospectively analyzed. The treatment outcome was known in 161 molars after patient drop-out (20 patients with 36 molars). The cases were categorized into 8 groups according to the choice of treatment: orthodontic uprighting, surgical-orthodontic uprighting, surgical uprighting, surgical repositioning, surgical exposure, first or second molar extraction, third molar extraction, or removal of pathologic conditions. RESULTS: The overall treatment outcome was positive in 141 molars (87.6%). It was positive in all cases treated with orthodontic uprighting (7 molars), surgical exposure (10 molars), surgical uprighting (38 molars), and surgical repositioning (8 molars), but it was significantly lower for surgical-orthodontic uprighting (34/48 molars, 70.8%). The positive outcome was significantly lower for inclusion (52/68 molars, 76.5%) than for early-diagnosed condition (11/11 molars, 100%) and retention (78/82 molars, 95.1%), and for total bone crown coverage (21/28 molars, 75.0%) than for osteomucosal or mucosal crown coverage (120/133 molars, 90.2%). CONCLUSIONS: This study demonstrates that an early diagnosis results in a better outcome regardless of the treatment used, with the number of cases with a positive outcome being higher in younger patients.

Sequelae in permanent teeth after traumatic injuries to primary dentition.

Traumatic injuries to the primary dentition are critical events in dentistry not only due to the need for urgent care, but also since they have potential sequelae in the permanent dentition, with a prevalence ranging from 12% to 74%. The aim of this article was to provide an overview of the prevalence, etiology, and clinical and radiographic characteristics as well as the management of permanent teeth sequelae resulting from traumatic injuries to their deciduous predecessors. An extensive literature review was performed to reveal the current evidence on enamel discoloration with or without hypomineralization/hypoplasia, crown dilaceration, odontoma-like malformation, root anomalies, partial or complete arrest of root formation, sequestration of the permanent tooth germ, and eruption disturbances.

Clinical and radiographic outcomes of a surgical reconstructive approach in the treatment of peri-implantitis lesions: A 5-year prospective case series.

OBJECTIVES: The aim of this study was to evaluate the 5-year clinical and radiographic outcomes following reconstructive therapy of peri-implantitis lesions using mineralized dehydrated bone allograft and resorbable membrane in the nonsubmerged mode of wound healing. MATERIALS AND METHODS: Thirty-four patients with at least one implant diagnosed with peri-implantitis were treated by mechanical debridement; chemical decontamination using hydrogen peroxide (3%), chlorhexidine (0.2%), and a tetracycline hydrochloride solution; and bone defect filling with mineralized dehydrated bone allograft and resorbable membrane. Clinical and radiographic assessments were obtained during 5-year follow-up. The primary outcome was the absence of additional marginal peri-implant bone loss ≥1.0 mm after surgery, and the composite outcome included the additional marginal peri-implant bone loss, absence of probing depth (PD) ≥5 mm, and absence of bleeding on probing (BoP)/suppuration. RESULTS: According to the primary and composite outcomes, the success rate of 34 implants included in the study was 100% and 91% (N = 31), at 1 year after surgery, and decreased progressively to 77% (N = 26) and to 59% (N = 20) at 5-year follow-up, respectively. Five years following treatment, only the BoP reduction was statistically significant compared to baseline (p < 0.001), and no difference was found in PD (p = 0.318) and in marginal peri-implant bone level (p = 0.064). CONCLUSIONS: At 1-year follow-up, the surgical reconstructive therapy showed clinical improvement and radiographic defect filling. However, the results appeared to be unpredictable over time, due to a progressive decrease in the bone filling of the peri-implant defects and an increase in the mean PD.

Efficacy of Preoperative Administration of Paracetamol-Codeine on Pain following Impacted Mandibular Third Molar Surgery: A Randomized, Split-Mouth, Placebo-Controlled, Double-Blind Clinical Trial.

Objectives. The aim of this study was to determine the effectiveness of preoperative administration of single-dose of paracetamol-codeine, in the relieving of acute postoperative pain after the surgical removal of an impacted mandibular third molar. Materials and Methods. The study cohort consisted of 32 Caucasian outpatients, giving a total of 64 bilateral symmetrical impacted mandibles. Patients were randomized in two experimental groups to receive a preoperative oral dose of paracetamol-codeine (analgesic group) or a placebo (placebo group) at the first and second surgeries. Study participants were asked to record pain intensity scores during the operation and the next 2 days, the time of the first request for rescue analgesic, and the total number of postoperative-supplement paracetamol-codeine tablets. Results. The pain intensity score on the first day was significantly lower in the analgesic group than in the placebo group (p < 0.001). The time to using rescue therapy was significantly longer in the analgesic group than in the placebo group (p = 0.004). The number of paracetamol-codeine tablets used postoperatively did not differ between the analgesic and placebo groups (p = 0.104). Conclusions. Preoperative paracetamol-codeine is effective in providing immediate postoperative pain control after third molar surgery and in delaying the initial onset of pain. This trial is registered with ClinicalTrials.gov Identifier (Registration Number): NCT03049878.

Prevention of neurological injuries during mandibular third molar surgery: technical notes.

Surgery to the mandibular third molar is common, and injuries to the inferior alveolar nerve and the lingual nerve are well-recognized complications of this procedure. The aim of these technical notes is to describe operative measures for reducing neurological complications during mandibular third molar surgery. The following procedure should be used to prevent damage to the inferior alveolar nerve: a well-designed mucoperiosteal flap, to obtain appropriate access to the surgical area; a conservative ostectomy on the distal and distal-lingual side; tooth sectioning, to facilitate its removal by decreasing the retention zones; tooth dislocation in the path of withdrawal imposed by the curvature of the root apex; and careful socket debridement, when the roots of the extracted tooth are in intimate contact with the mandibular canal. To prevent injury to the lingual nerve, it is important (I) to assess the integrity of the mandibular inner cortex and exclude the presence of fenestration, which could cause the dislocation of the tooth or its fragment into the sublingual or submandibular space; (II) to avoid inappropriate or excessive dislocation proceedings, in order to prevent lingual cortex fracture; (III) to perform horizontal mesial-distal crown sectioning of the lingually inclined tooth; (IV) to protect the lingual flap with a retractor showing the cortical ridge; and (V) to pass the suture not too apically and from the inner side in a buccal-lingual direction in the retromolar area.

Is erbium:yttrium-aluminum-garnet laser versus conventional rotary osteotomy better in the postoperative period for lower third molar surgery? Randomized split-mouth clinical study.

PURPOSE: Lasers have been extensively used in dentistry for several applications. We investigated and compared the use of an erbium:yttrium-aluminum-garnet laser and conventional rotary instruments for bone removal in third molar surgery. MATERIALS AND METHODS: We implemented a randomized, split-mouth clinical trial. Patients with bilateral and symmetrical third molar impaction referred to the Department of Oral and Maxillo-Facial Sciences, "Sapienza" University of Rome, were enrolled in the study. Each patient was treated once with the erbium:yttrium-aluminum-garnet laser and once with conventional rotary instruments for bone removal during third molar surgery. Pain, swelling, and trismus were taken into account to match the 2 techniques.In addition, the times required to complete osteotomy and for the full operation were recorded. Descriptive and bivariate statistics were computed, and the P value was set at .05. RESULTS: The sample was composed of 15 patients (8 men and 7 women) ranging in age from 18 to 30 years. Pain perceived in the laser-treated group was significantly less than that in the conventional group(P = .0013). This also was true for trismus (P = .0002) and swelling. The operating time for osteotomy was longer in the laser group. CONCLUSIONS: The results of this study suggest that the laser could be an interesting alternative to conventional rotary instruments. Future studies with a larger number of patients are required to confirm the conclusions achieved from this work.

The "CROMa" Project: A Care Pathway for Clinical Management of Patients with Bisphosphonate Exposure.

Aim. To describe 7 years of activity of "CROMa" (Coordination of Research on Osteonecrosis of the Jaws) project of "Sapienza" University of Rome. Materials and Methods. A preventive and therapeutic care pathway was created for patients with bisphosphonates (BPs) exposure. Demographic, social, behavioural, pharmacological, and clinical variables were registered in a dedicated database. Results. In the project, 502 patients, 403 females and 99 males, were observed. Bone pathologies were 79% osteometabolic diseases (OMD) and 21% metastatic cancer (CA). Females were 90% in OMD group and 41% in CA. BP administration was 54% oral, 31% IV, and 11% IM; 89% of BPs were amino-BP and 11% non-amino-BP. Consistently with bone pathology (OMD/CA), alendronate appears to be prevalent for OMD (40% relative), while zoledronate was indicated in 92% of CA patients. Out of 502 cases collected, 28 BRONJ were detected: 17 of them were related to IV BP treatment. Preventive oral assessment was required for 50% of CA patients and by 4% of OMD patients. Conclusions. The proposed care pathway protocols for BP exposed patients appeared to be useful to meet treatment and preventive needs, in both oncological and osteometabolic diseases patients. Patients' and physicians' prevention awareness can be the starting point of a multilevel prevention system.

Micro-CT and PET analysis of bone regeneration induced by biodegradable scaffolds as carriers for dental pulp stem cells in a rat model of calvarial "critical size" defect: Preliminary data.

Bone regeneration strategies in dentistry utilize biodegradable scaffolds seeded with stem cells able to induce bone formation. However, data on regeneration capacity of these tissue engineering constructs are still deficient. In this study micro-Computed tomography (micro-CT) and positron emission tomography (PET) analyses were used to investigate bone regeneration induced by two scaffolds [Granular deproteinized bovine bone (GDPB) and Beta-tricalcium phosphate (ß-TCP)] used alone or in combination with dental pulp stem cells (DPSC) in a tissue engineered construct implanted in a rat critical calvarial defect. Bone mineral density (BMD) and standard uptake value (SUV) of tracer incorporation were measured after 2, 4, 8, and 12 weeks post-implant. The results showed that: (1) GDPB implants were mostly well positioned, as compared to ß-TCP; (2) GDPB induced higher BMD and SUV values within the cranial defect as compared to ß-TCP, either alone or in combination with stem cells; (3) addition of DPSC to the grafts did not significantly induce an increase in BMD and SUV values as compared to the scaffolds grafted alone, although a small tendency to increase was observed. Thus our study demonstrates that GDPB, when used to fill critical calvarial defects, induces a greater percentage of bone formation as compared to ß-TCP. Moreover, this study shows that addition of DPSC to pre-wetted scaffolds has the potential to ameliorate bone regeneration process, although the set of optimal conditions requires further investigation.

A comparative morphometric analysis of biodegradable scaffolds as carriers for dental pulp and periosteal stem cells in a model of bone regeneration.

Bone regeneration and bone fixation strategies in dentistry utilize scaffolds containing regenerating-competent cells as a replacement of the missing bone portions and gradually replaced by autologous tissues. Mesenchymal stem cells represent an ideal cell population for scaffold-based tissue engineering. Among them, dental pulp stem cells (DPSCs) and periosteal stem cells (PeSCs) have the potential to differentiate into a variety of cell types including osteocytes, suggesting that they can be used with this purpose. However, data on bone regeneration properties of these types of cells in scaffold-based tissue engineering are yet insufficient.In this study, we evaluated temporal dynamic bone regeneration (measured as a percentage of bone volume on the total area of the defect) induced by DPSCs or PeSCs when seeded with different scaffolds to fill critical calvarial defects in SCID Beige nude mice. Two commercially available scaffolds (granular deproteinized bovine bone with 10% porcine collagen and granular ß;-tricalcium phosphate) and one not yet introduced on the market (a sponge of agarose and nanohydroxyapatite) were used. The results showed that tissue-engineered constructs did not significantly improve bone-induced regeneration process when compared with the effect of scaffolds alone. In addition, the data also showed that the regeneration induced by ß;-tricalcium phosphate alone was higher after 8 weeks than that of scaffold seeded with the 2 stem cell lines. Altogether these findings suggest that further studies are needed to evaluate the potential of DPSCs and PeSCs in tissue construct and identify the appropriate conditions to generate bone tissue in critical-size defects.

Human maxillary sinuses augmented with mineralized, solvent-dehydrated bone allograft: a longitudinal case series.

BACKGROUND: This prospective case series aimed to assess the clinical stability of maxillary sinus floors regenerated with mineralized, solvent-dehydrated bone allograft (MSDBA) and restored with dental implants after at least 5 years of function. MATERIALS AND METHODS: Eleven sinuses in 7 patients (4 bilateral) were augmented with 50% cortical and 50% cancellous MSDBA (Puros, Zimmer Dental Italy srl, Vittorio Veneto, Treviso, Italy). After a mean healing period of 8.1 months, a total of 11 bone specimens (1 per sinus graft) were retrieved and 25 implants were placed. Bone samples were analyzed using histology, histomorphometry, and immunohistochemistry. Standardized periapical radiographs were taken at prosthetic loading (baseline) and annually. RESULTS: There were no complications or failures. Histologically, almost all residual MSDBA particles were surrounded by bone. Histomorphometry characterized the tissue as 39% ± 1.6% newly formed bone, 34% ± 1.6% marrow spaces, and 31% ± 1.4% residual material reflective of high cortical content of the composite graft. Immunohistochemistry indicated that osteoblasts expressed OB-cadherin at high levels. After a mean follow-up of 5.1 years, implants and regenerated bone appeared clinically stable. Radiographically, implants appeared to be surrounded by dense bone and ridges did not lose clinically measurable volume. CONCLUSIONS: Composite MSDBA allografts formed good quality maxillary sinus bone without complications after 8.1 months of mean healing time, and demonstrated clinical and radiographic stability after a mean follow-up time of 5.14 years.

Fused upper central incisors: management of two clinical cases.

This paper reports the management of two clinical cases, in which the upper right central incisor was fused with a supernumerary tooth and the upper left central incisor was macrodontic. A radiographic examination revealed that the fused teeth had two separate roots. Hemisectioning of the fused teeth was performed, the supernumerary portion was extracted and the remaining part was reshaped to remove any sharp margins and to achieve a normal morphology. The macrodontic central incisors were not treated. At 12-months post-surgery there were no periodontal problems and no hypersensitivity. Orthodontic treatment was performed to appropriately align the maxillary teeth and to correct the malocclusion.

Local accidents in dental implant surgery: prevention and treatment.

Many articles have detailed local accidents and complications in dental implant treatment. Comparisons of the data they report are not always easy because different criteria have been followed in the various classifications and there is confusion between the terms accident and complication. The aim of this paper is to propose a classification that considers the timing of the events and makes a distinction between the two terms. Accidents are events that occur during surgery, and complications are any pathologic conditions that appear postoperatively. The proper diagnostic procedures and surgical techniques for their prevention and treatment are also described.

The role of the template in prosthetically guided implantology.

In prosthetically guided implantology, where ideal placement of implants is determined by the definitive restoration, the use of a radiographic/surgical template plays an essential role. This article describes how to fabricate a radiographic/surgical template to be used for radiographic diagnosis of the selected implant sites and as a guide during surgery for the insertion of the implant with correct angulation.