Combination of real-time needle-tip pressure sensing and minimal intensity stimulation limits unintentional intraneural injection during an ultrasound-guided peripheral nerve block procedure: A randomized, parallel group, controlled trial.

STUDY OBJECTIVE: Ultrasound guidance does not eliminate the risk of intraneural injection, which must be avoided during PNB. Combining ultrasound guidance (USG), nerve stimulation (NS), and injection pressure monitoring is advocated to prevent nerve injury during PNB. We hypothesized that combining patient-tailored dynamic NS and real-time pressure sensing (RTPS) could reduce the incidence of intraneural injection and nerve puncture during USG PNB compared with a traditional fixed thresholds (Control) procedure. DESIGN: Randomized, prospective study. SETTING: Operating room. PATIENTS: One hundred ASA physical status I to III patients undergoing orthopedic surgery. INTERVENTIONS: Patient anesthetized using axillary, sciatic or femoral USG PNB were randomized to the PresStim group (Dynamic RTPS and NS set at 1.5 mA then decreased; n = 50) or Control group (fixed thresholds for in-line pressure mechanical manometer and NS at 0.2 mA; n = 50). MEASUREMENTS: Procedural ultrasound images and videos were recorded, stored and reviewed in random order by two experts in ultrasound-guided PNB blinded to the group. They noted the needle-to-nerve relationship and intraneural injection for all blocked nerves. MAIN RESULTS: One hundred and twenty-three USG PNBs were performed (56 axillary brachial plexus blocks, 40 femoral nerve blocks and 27 sciatic popliteal nerve blocks); 235 blocked nerves and videos were recorded and analyzed (PresStim, 118; Control, 117). Less paresthesia was noted in the PresStim group (12.7%) compared with the Control group (18.8%). The risk of intraneural injection was significantly higher in the Control group (odds ratio [OR], 17.1; 95% confidence interval [CI], 2.2-135, P = 0.007). The risk of nerve puncture (OR, 22.7; 95% CI, 2.9-175, p = 0.003) and needle-nerve contact (OR, 4.7; 95% CI, 2.4-9.5, p < 0.001) was significantly higher in the Control group than the PresStim group. CONCLUSIONS: Under the conditions of the study, dynamic triple monitoring combining RTPS, NS and USG decreases intraneural injection and unintentional needle-nerve contact and puncture during a PNB procedure.

Analysis of Epidural Waveform to Determine Correct Epidural Catheter Placement After CSE Labor Analgesia.

BACKGROUND: The epidural pressure is pulsatile and synchronized with arterial pulsations. Monitoring the epidural waveform has been suggested as a technique to reliably confirm the appropriate localization of the epidural catheter. OBJECTIVE: The aim of this study was to evaluate the sensitivity and specificity of the Computer Controlled Drug Delivery System with continuous pressure and waveform sensing technology (CCDDS) (CompuFlo® CathCheck™) as an instrument to assess the correct placement of the catheter in the epidural space in parturients who have received combined spinal-epidural technique (CSE) for labor analgesia. METHODS: We enrolled 40 consecutive healthy patients undergoing CSE labor analgesia with successful analgesia. All the cases in which pulsatile waveforms in synchrony with heart rate were detected were considered to be true positives; all the cases in which there was the absence of pulsatile waves were followed up. If these patients had to eventually relocate or manipulate the epidural catheter, they were considered to be true negative. If the absence of pulse waves was observed in the presence of successful analgesia during labor, the patients were considered to be false negatives. RESULTS: Pulsatile waveforms synchronous with heart rate were observed in 33 cases associated with adequate analgesia. In 5 cases, the pulsatile waveforms were absent due to unilateral analgesia or catheter occlusion (true negatives). In 2 cases, the patients had effective analgesia but we were not able to observe a distinct pulsatile waveform. The pressure waveform analysis through the epidural catheter had a sensitivity of 95%, a positive predictive value of 100%, a specificity of 100% and a negative predictive value of 60%. CONCLUSION: Pulsatile pressure waveform recording with CCDDS through the epidural catheter resulted in high sensitivity and positive predictive value which can help the proper placement of the epidural catheter.

A New Definition of Attached Gingiva Around Teeth and Implants in Healthy and Diseased Sites.

There is a need to modify the definition of attached gingiva (AG) as it applies to healthy and diseased teeth and implants. There are two parts to this new definition: Part A is when the biologic width is supracrestal (epithelial attachment and gingival fibers) and is attached to a healthy tooth or tissue-level implant, and the zone of AG is measured from the base of the sulcus to the mucogingival junction (MGJ); Part B is when the biologic width is subcrestal-as with infrabony defects on periodontally involved teeth, periodontally involved tissue-level implants, and bone-level implants placed at or below the bone crest-and the zone of AG is measured from the bone crest (not the base of the sulcus) to the MGJ. Further, what the AG is actually attached to around teeth and different types of implants, and the clinical significance of these differences, are thoroughly discussed.

Objective Epidural Space Identification Using Continuous Real-Time Pressure Sensing Technology: A Randomized Controlled Comparison With Fluoroscopy and Traditional Loss of Resistance.

BACKGROUND: Performance of epidural anesthesia and analgesia depends on successful identification of the epidural space (ES). While multiple investigations have described objective and alternative methodologies to identify the ES, traditional loss of resistance (LOR) and fluoroscopy (FC) are currently standard of care in labor and delivery (L&D) and chronic pain (CP) management, respectively. While FC is associated with high success, it exposes patients to radiation and requires appropriate radiological equipment. LOR is simple but subjective and consequently associated with higher failure rates. The purpose of this investigation was to compare continuous, quantitative, real-time, needle-tip pressure sensing using a novel computer-controlled ES identification technology to FC and LOR for lumbar ES identification. METHODS: A total of 400 patients were enrolled in this prospective randomized controlled noninferiority trial. In the CP management arm, 240 patients scheduled to receive a lumbar epidural steroid injection had their ES identified either with FC or with needle-tip pressure measurement. In the L&D arm, 160 female patients undergoing lumbar epidural catheter placements were randomized to either LOR or needle-tip pressure measurement. Blinded observers determined successful ES identification in both arms. A modified intention-to-treat protocol was implemented, with patients not having the procedure for reasons preceding the intervention excluded. Noninferiority of needle-tip pressure measurement regarding the incidence of successful ES identification was claimed when the lower limit of the 97.27% confidence interval (CI) for the odds ratio (OR) was above 0.50 (50% less likely to identify the ES) and P value for noninferioirty <.023. RESULTS: Demographics were similar between procedure groups, with a mild imbalance in relation to gender when evaluated through a standardized difference. Noninferiority of needle-tip pressure measurement was demonstrated in relation to FC where pain management patients presented a 100% success rate of ES identification with both methodologies (OR, 1.1; 97.27% CI, 0.52-8.74; P = .021 for noninferiority), and L&D patients experienced a noninferior success rate with the novel technology (97.1% vs 91%; OR, 3.3; 97.27% CI, 0.62-21.54; P = .019) using a a priori noninferiority delta of 0.50. CONCLUSIONS: Objective lumbar ES identification using continuous, quantitative, real-time, needle-tip pressure measurement with the CompuFlo Epidural Computer Controlled Anesthesia System resulted in noninferior success rates when compared to FC and LOR for CP management and L&D, respectively. Benefits of this novel technology may include nonexposure of patients to radiation and contrast medium and consequently reduced health care costs.

Layperson's Esthetic Preference to the Presence or Absence of the Interdental Papillae in the Low Smile Line: A Web-based Study.

PURPOSE: To determine the layperson's esthetic preference to the visual display (presence) or lack thereof (absence) of the interdental papillae during minimum smiling or the low smile line patient type. MATERIALS AND METHODS: Two hundred lay-people were shown three-paired smile images indicative of a low gingival smile line patient type in which the vermillion border of the maxillary lip covered the mid-facial gingiva of the anterior teeth. The three images differed only with respect to [1] presence of interdental papillae, [2] absence of the interdental papilla ("black triangle"), or [3] absence of the interdental papillae (replaced with a long restorative contact area). The three images were paired in multiple groupings; group-1 consisted of a comparison of the presence of interdental papillae vs the lack of the interdental papillae "black triangle," group-2 compared the long restorative contact compared to the presence of the interdental papillae and Group-3 compared the long restorative contact replacing a missing papilla to the absence of the interdental papillae "black triangle." The comparisons were designed to determine the subjective preference of lay individuals between these groupings. RESULTS: Ninety-eight percent of lay-people demonstrated a preference to the presence of the interdental papillae in the smile (image 1) when compared to its absence ("black triangle"; image 2) with a low smile line. Seventy percent preferred the visual display of the interdental papillae, that is, pink tissues (image 1), compared to the absence of the interdental papillae replaced with a long contact area (image 3), that is, white restorative materials, when viewing a low gingival smile line. And when comparing the absence of the interdental papillae "black triangle" to a long contact area, 92% of lay-people preferred a long contact area vs the absence of the interdental papillae with a "black triangle" with a low smile line. CONCLUSIONS: The visual display [presence] of the interdental papillae, that is, pink tissues, is notably preferred to the absence of the interdental papillae when replaced by either a "black triangle" or long contact area in the commonly known low smile line. This emphasizes the need to assess the Interdental Smile Line (ie, visual display of interdental papillae during smiling) in all patients and the importance to preserve and/or re-establishment of the interdental papillae, that is, pink tissues, even in patients with a low smile line.

Flapless Postextraction Socket Implant Placement: The Effects of a Platform Switch-Designed Implant on Peri-implant Soft Tissue Thickness-A Prospective Study.

This paper presents the results of a prospective study on the clinical effect of grafting the buccal gap with platform switching, following flapless tooth extraction and immediate implant placement and provisional restoration, on (1) alterations in buccolingual ridge dimension and (2) midfacial peri-implant soft tissue thickness. Fifty-six patients were placed in one of four treatment groups: (1) a non-platform-switching implant (Non-PS, n = 14); (2) a non-platform-switching implant and bone graft (BG/Non-PS, n = 14); (3) a platform-switching implant (PS, n = 15); and (4) a platform-switching implant and bone graft (BG/PS, n = 13). Buccolingual ridge dimensional change and peri-implant soft tissue thickness at 2 mm below the free gingival margin were measured. Both PS and BG/PS groups showed an increase in buccolingual dimension compared to the contralateral natural tooth site as well as peri-implant soft tissue thickness of > 2.5 mm, clinically. Platform switching was associated with significantly greater midfacial soft tissue thickness than bone grafting (mean ± standard deviation: 2.17 ± 0.04 for Non-PS and 3.55 ± 0.14 for PS). Using platform-switched implants, in conjunction with immediate implant placement and immediate provisional restoration, was associated with a significantly greater stability of ridge dimension and peri-implant soft tissue thickness than using non-platform-switched implants when measured 12 months after placement of the final restoration. Platform switching may help achieve preservation of ridge dimension and enhance the stability of peri-implant soft tissue following immediate implant placement and provisional restoration without bone grafting. Further research is required to assess the long-term outcome.

Subclassification and Clinical Management of Extraction Sockets with Labial Dentoalveolar Dehiscence Defects.

Immediate implant therapy involving implants placed into intact Type 1 extraction sockets has become a consistent clinical technique. The classification of Type 2 extraction sockets, where the mucosal tissues are present but there is a midfacial osseous dehiscence defect, has been described according to the extent of the buccal bone plate absence. The literature has offered different techniques in the treatment of Type 2 sockets; however, the extent of the defect has never been defined or delineated. In this article, the authors describe a subclassification of Type 2 sockets: Type 2A presents with a dehiscence defect roughly 5 mm to 6 mm from the free gingival margin (FGM) involving the coronal one-third of the labial bone plate; Type 2B presents with a dehiscence defect involving the middle one-third of the labial plate, approximately 7 mm to 9 mm from the FGM; and in Type 2C the dehiscence defect involves the apical one-third of the labial osseous plate roughly 10 mm or greater from the FGM. The authors also offer a protocol and technique employing immediate implant placement, guided bone regeneration, and bone graft containment with a custom two-piece healing abutment that can lead to consistent and satisfactory clinical outcomes in low-smile-line patients. The treatment protocol and sequence is outlined in a clinical case presentation involving a Type 2B socket.

A novel prosthetic device and method for guided tissue preservation of immediate postextraction socket implants.

Preservation of the surrounding hard and soft tissues associated with an immediate postextraction socket implant to replace a nonrestorable tooth in the esthetic zone is one of the greatest challenges facing the dental team. Several studies have documented the biologic and esthetic benefits of bone graft containment with either a custom healing abutment or provisional restoration. Use of a prefabricated shell that replicates the extracted tooth at the cervical region can help achieve guided tissue preservation and sustainable esthetic outcomes in an easy, simple, consistent, and less time consuming way. The following case report of a hopeless maxillary right central incisor in a female patient possessing adjacent teeth with a thin periodontal phenotype illustrates this new treatment device, method, and concept.

Maxillary anterior papilla display during smiling: a clinical study of the interdental smile line.

The purpose of this research was to quantify the visual display (presence) or lack of display (absence) of interdental papillae during maximum smiling in a patient population aged 10 to 89 years. Four hundred twenty digital single-lens reflex photographs of patients were taken and examined for the visual display of interdental papillae between the maxillary anterior teeth during maximum smiling. Three digital photographs were taken per patient from the frontal, right frontal-lateral, and left frontal-lateral views. The data set of photographs was examined by two examiners for the presence or absence of the visual display of papillae. The visual display of interdental papillae during maximum smiling occurred in 380 of the 420 patients examined in this study, equivalent to a 91% occurrence rate. Eighty-seven percent of all patients categorized as having a low gingival smile line (n = 303) were found to display the interdental papillae upon smiling. Differences were noted for individual age groups according to the decade of life as well as a trend toward decreasing papillary display with increasing age. The importance of interdental papillae display during dynamic smiling should not be left undiagnosed since it is visible in over 91% of older patients and in 87% of patients with a low gingival smile line, representing a common and important esthetic element that needs to be assessed during smile analysis of the patient.

A biometric approach to aesthetic crown lengthening: part II--interdental considerations.

Optimizing the aesthetic outcome for patients requiring periodontal aesthetic restorative treatment has become a primary objective in contemporary dentistry. Techniques that simplify and enhance quality of treatment provide substantial benefits to patients and clinicians. This article describes new concepts associated with interdental changes due to alterations in tooth and contact area position, and addresses the need for treatment of the interdental papillae. An innovative approach to aesthetic interdental periodontal crown lengthening will be discussed.

A biometric approach to aesthetic crown lengthening: part I--midfacial considerations.

Although human dental anatomy is taught in university curricula, clinicians often witness restorations that are not proportional to one another. Dental restorations should also be proportional to periodontal supporting tissues as an essential aspect of dental anatomy. Measurements can be performed directly on a patient's teeth with aesthetic gauges used to confirm the correct position of the supporting osseous topography. This article demonstrates a technique using these gauges to objectively determine the correct position of the underlying hard tissues and render predictable, aesthetic treatment.

A prospective clinical patient study evaluating the effect of increasing anesthetic volume on inferior alveolar nerve block success rate.

OBJECTIVE: The purpose of this study was to clinically evaluate an anesthetic technique in which a second cartridge was reloaded in a traditional dental syringe and reinjected at the same site in regard to success rate of the attempted inferior alveolar nerve block. During the same appointment, a computer-controlled delivery system was used on the opposite side of the same patient to administer 2 cartridges as well. Successful anesthesia and time efficiency of the traditional syringe and computer-controlled technique were then evaluated and compared. METHOD AND MATERIALS: Thirty-five subjects between the ages of 18 and 58 years were randomly assigned to both the traditional syringe delivery system using a standardized 2-cartridge reloading and reinjection technique and a computer-controlled system using a technique whereby the second cartridge was reloaded without having to remove the needle from the injection site. Subjects served as their own controls. Successful anesthesia was achieved when all soft tissues innervated by the inferior alveolar and lingual nerves were nonresponsive to painful stimulation with an explorer as evaluated at 3- and 10-minute intervals following final anesthetic administration. The time necessary to reload the second cartridge for each side was measured, as was the time necessary to deliver the second full 1.8-mL cartridge. RESULTS: Two-cartridge delivery with the traditional syringe resulted in a 94.3% success rate at 3 minutes and a 100% success rate at 10 minutes; 2-cartridge delivery with the computer-controlled delivery system resulted in an 80% success rate at 3 minutes and a 91.4% success rate at 10 minutes following final injection. Reloading time for the second cartridge was 11.37 seconds less with the computer-controlled delivery system, but no statistical difference was found between the 2 systems regarding time to deliver the second cartridge. CONCLUSIONS: The results for the 2-cartridge technique with both systems compare favorably with and surpass the accepted 85% success rate reported in the dental literature with only 1 cartridge. The computer-controlled delivery system did not require needle removal and was more time efficient at reloading than the traditional syringe system.

Single-tooth anesthesia: pressure-sensing technology provides innovative advancement in the field of dental local anesthesia.

This article will review standard techniques for intraligamentary injection and describe the technology and technique behind a new single-tooth anesthesia system. This system and technique represents a technological advancement and a greater understanding of intraligamentary anesthesia.

Interstitial tissue pressure associated with dental injections: a clinical study.

OBJECTIVES: The purpose was to measure the interstitial fluid pressure generated from tissue resistance during administration of local anesthetic solution at 4 anatomic locations within the oral cavity and to determine whether differences in soft tissue density affect interstitial fluid pressure when anesthetic solution is administered at a fixed flow rate. METHOD AND MATERIALS: A computer-controlled local anesthetic delivery device (CompuFlo, Milestone Scientific) that records and stores pressure data during a subcutaneous injection was used. Subjects consisted of adult patients seeking routine dental care that required local anesthesia. A total of 200 injections were administered and fluid pressure readings recorded. Injections were divided into 4 groups of 50: group 1--intraligamentary injections (PDL); group 2--palatal injection, anterior middle superior alveolar nerve block; group 3--supraperiosteal buccal infiltrations, and group 4--inferior alveolar nerve blocks. For all injections 1 cartridge (1.8 mL) of lidocaine containing 1:100,000 concentration of epinephrine was administered at a fixed flow rate of 0.005 mL/sec. RESULTS: One-way analysis of variance (ANOVA) revealed that the data were statistically significant (P < .001), with corresponding mean values as follows: group 1, 293.98 psi; group 2, 68.16 psi; group 3, 11.50 psi, and group 4, 9.76 psi (F-ratio of 2371.933). Groups 1 and 2 were different from all other groups; groups 3 and 4 were not statistically different from each other. CONCLUSION: Interstitial resistance to fluid pressure can be measured during administration of 4 different local anesthetic injections used in dentistry. Based on fluid pressure and tissue resistance characteristics, a soft tissue density classification was defined.