Determination of the mental foramen position in dental radiographs in 18-30 year olds.

OBJECTIVES: To determine the radiographic position and reliability of assessing mental foramen (MF) position in relation to premolar crowns in an 18- to 30-year-old UK-based population. METHODS: Following ethical approval and a power calculation, the position of the MF was recorded in relation to premolar crowns and apices in 100 dental panoramic tomographs. Positions were assessed by three senior clinicians independently, then by consensus. Data were analysed using descriptive statistics, χ(2) and Fleiss' and Cohen's kappa. RESULTS: Reliability data showed only fair to moderate agreement on independent scoring. Substantial to almost perfect agreement was achieved by consensus, demonstrating the most common position for the MF to be between the first and second premolar teeth when using both premolar crowns (51%) and apices (76%) as reference points. There was a significant difference in the position of the foramen between the left and right sides (p < 0.05), with only 62% of cases showing symmetry. CONCLUSIONS: The most common position for the MF is between the first and second premolar teeth; however, anatomical variation is seen. Use of pre-operative radiographs to relate the position of the MF to premolar crowns may not be reliable.

Haemostasis. Part 2: Medications that affect haemostasis.

Post-operative haemorrhage is a recognized complication in dental practice. This may be more prevalent in patients taking antithrombotic medications. It is important that the dentist understands the mechanism of action of these drugs and how they may affect management of dental patients. Clinical Relevance: Dental professionals must be aware of those medications affecting haemostasis and how they may impact on management. The emergence of different therapeutic regimens has increased the number of such drugs.

Haemostasis. Part 1: The management of post-extraction haemorrhage.

UNLABELLED: The management of bleeding complications following a dental extraction is an essential skill for the dental practitioner. Extractions are often carried out on patients with complex medical histories and a long list of medications. This paper aims to help the clinician manage post-extraction haemorrhage. A review of the management of patients on anti-thrombotic medications will be covered in a subsequent paper. CLINICAL RELEVANCE: This article reviews the management of haemorrhage following tooth extraction; from the risk assessment of any underlying medical conditions and medications, to the clinical techniques used to control bleeding following an extraction.

Use of Pre-Injection Diffusion of Local Anaesthetic as a Means of Reducing Needle Penetration Discomfort.

AIM: To determine if pre-injection diffusion of local anaesthetic solution influences the discomfort of needle penetration in the palate. METHODS: A placebo-controlled, randomised, double-blind split-mouth investigation was conducted. 25 healthy adult volunteers were recruited and each received two needle penetrations in a random order during one visit. The penetration sites were 1 cm from the gingival margin of the first maxillary premolars on each side of the mouth. 30 gauge-13 mm needles which were attached to syringes that contained either 2% lidocaine with 0.125mg/ml epinephrine or physiological saline were used. For each penetration an operator encouraged a drop of solution to appear at the end of the needle and placed this drop with the bevel of the needle flat on the palate for 20 seconds. The discomfort was noted on a 100 mm visual analogue scale with end points marked "No pain" and "Unbearable pain". RESULTS: There was no significant difference in penetration discomfort between solutions, (mean VAS = 26.80±19.36mm for lidocaine and 26.20±18.39mm for saline) however the 2nd penetration was significantly more uncomfortable than the first (mean VAS = 31.00±19.84 mm and 22.00±16.65 mm respectively). CONCLUSION: Pre-injection diffusion of local anaesthetic solution did not influence the discomfort of needle penetration in the palate.

Is mandibular molar buccal infiltration a mental and incisive nerve block? A randomized controlled trial.

INTRODUCTION: The aim of this study was to compare the efficacies of buccal local anesthetic infiltrations at various sites of the mandible in order to elucidate the mechanism of action of articaine mandibular infiltrations. METHODS: After a power calculation and ethical approval, 22 volunteers received 1.8 mL 4% articaine hydrochloride with 1:100,000 adrenaline as a buccal infiltration at the canine, first, or second molar in a randomized, double-blind, crossover design. The injections at the canine and first molar were considered equidistant from the mental foramen. Responses of the first and second molars, first premolar, and lateral and central incisors were assessed using an electronic pulp tester over a 47-minute period. Volunteers were asked to rate the discomfort of each injection using a visual analog scale. Data were analyzed using repeated measures analysis, McNemar, and Mann-Whitney U testing. RESULTS: Injections at the canine and first molar teeth produced anesthesia in all teeth tested in some volunteers. There was no significant difference between anesthetic success of the first premolar after infiltration at the canine or the first molar. Injection at the second molar failed to produce anesthesia of the incisor teeth. Anesthesia was significantly more likely after injections at an adjacent site. There was no difference in discomfort associated with injections at different sites of the mandible. CONCLUSIONS: Articaine first mandibular molar infiltrations achieve an effect via a combination of modified mental and incisive nerve block and local infiltration. Infiltration at the second molar produces anesthesia of both molar and premolar teeth, primarily via infiltration.

A comparison of the efficacy of 4% articaine with 1:100,000 epinephrine and 2% lidocaine with 1:80,000 epinephrine in achieving pulpal anesthesia in maxillary teeth with irreversible pulpitis.

INTRODUCTION: To assess the efficacy of buccal infiltrations of 4% articaine with 1:100,000 epinephrine and 2% lidocaine with 1:80,000 epinephrine in achieving anesthesia in maxillary teeth with irreversible pulpitis. METHODS: This randomized double-blind clinical trial included 100 patients diagnosed with irreversible pulpitis in maxillary teeth. Patients received 2.0 mL 4% articaine with 1:100,000 epinephrine or 2% lidocaine with 1:80,000 epinephrine in the buccal sulcus adjacent to the tooth with pulpitis. Before and every 2 minutes up to a maximum of 10 minutes after injection, the response of the test tooth was assessed using an electronic pulp tester. Successful pulp anesthesia was considered to have occurred when no response was obtained to the maximum stimulation (80 reading) of the pulp tester during the test period, at which time treatment commenced. Treatment was regarded as being successfully completed when it was associated with no pain. The time to onset of successful pulp anesthesia was recorded for each test tooth. Injection discomfort was recorded on standard 100-mm visual analog scales (VASs). Data were analyzed by the Chi-square and Student t tests. RESULTS: Fifty patients received articaine and 50 received lidocaine. Seventy-three of the 100 patients achieved pulpal anesthesia within 10 minutes of injection: 38 after articaine and 35 after lidocaine (P = .5). The onset of pulpal anesthesia after articaine and lidocaine buccal infiltrations was similar (mean and standard deviations: 4.9 ± 2.7 minutes vs 5.1 ± 2.4 minutes, respectively; t = 0.2; P = .82). Pain-free treatment was completed in 33 patients after articaine and 29 after lidocaine buccal infiltrations (P = .63). Although articaine buccal injection was significantly more comfortable than lidocaine buccal injection (t = 2.3, P = .026), both were associated with mild discomfort on VAS (means ± standard deviation: 10.8 mm ± 11.7 mm vs 17.5 mm ± 17.6 mm, respectively). CONCLUSIONS: There was no significant difference in efficacy between 4% articaine with 1:100,000 epinephrine and 2% lidocaine with 1:80,000 epinephrine in achieving anesthesia in maxillary teeth with irreversible pulpitis after buccal infiltration.

The use of the mandibular infiltration anesthetic technique in adults.

BACKGROUND: The author describes the use of the infiltration anesthetic technique to anesthetize mandibular teeth in adults and explores its mechanism of action. METHODS: The author reviewed articles describing randomized controlled trials of the mandibular infiltration anesthetic technique in healthy participants. RESULTS: The author found that using the mandibular infiltration anesthetic technique can produce anesthesia in adult mandibular teeth. The success was dose dependent and the choice of anesthetic solution was significant; 4 percent articaine with 1:100,000 epinephrine was more effective than 2 percent lidocaine with 1:100,000 epinephrine. Combining buccal and lingual infiltrations increased success in the mandibular incisor region. The success of the mechanism of infiltration of anesthetic at the mandibular first molar appeared to depend on the mental foramen. CONCLUSIONS: The mandibular infiltration anesthetic technique is an effective method of anesthetizing mandibular incisors. Four percent articaine with epinephrine appears to be the preferred solution. CLINICAL IMPLICATIONS: The choice of anesthetic solution is important when using the infiltration anesthetic technique in the adult mandible.

The Oral Health Impact Profile: ranking of items for temporomandibular disorders.

The study aimed to rank the Oral Health Impact Profile (OHIP-49) items by relevance to temporomandibular disorders (TMD). A modified version of the OHIP-49 was completed by 110 patients with TMD and by age- and gender-matched TMD-free individuals. Patients were diagnosed using the Research Diagnostic Criteria (RDC) for TMD. The modified OHIP included a reference to the 'jaw' and a 1-month reference period. The difference in item prevalence for problems reported fairly/very often (FOVO) between the two groups was calculated for each OHIP item. The FOVO prevalence differences were ranked to reveal the most relevant problems for TMD. Patients' total OHIP scores were higher (60.6, SD = 31.6) than those of controls (17.1, SD = 18.1). Patients scored higher on all items, with 41 items showing a statistically significant difference between the patient score and the control score. The patient-control difference in FOVO item prevalence varied considerably between different items, ranging from 1 to 67%. Substantial differences were noted between patients and controls for a number of specific items, including those relating to pain and physical impact. Smaller differences across most items were also noted, even those not expected to have an impact. The OHIP provides a starting point for a measure of TMD treatment outcome, once items less attributable to TMD are excluded.

A comparison of the anterior middle superior alveolar nerve block and infraorbital nerve block for anesthesia of maxillary anterior teeth.

BACKGROUND: The authors conducted a study to compare the efficacy of the anterior middle superior alveolar (AMSA) nerve block with that of the infra-orbital nerve block (IONB) in achieving pulpal anesthesia in the anterior maxilla. METHODS: Twenty-eight healthy adult volunteers received 1.0 milliliter of 2 percent lidocaine with 1:80,000 epinephrine as an AMSA nerve block or IONB via computer-controlled local anesthetic delivery (CCLAD) across two visits. The authors used electronic pulp testing to measure pulpal anesthesia. Participants provided subjective reports of lip numbness and injection discomfort. The authors analyzed the data by using the McNemar, Mann-Whitney and t tests. RESULTS: Anesthetic success, defined as two or more consecutive episodes of no sensation in response to maximal stimulation, was significantly greater with the AMSA nerve block than with the IONB in central (P = .012) and lateral (P < .001) incisors; however, anesthesia was achieved in only 42.9 percent of central incisors with the AMSA nerve block. The authors observed a significantly greater number of episodes of no response in the premolar and canine teeth after IONB. Onset of anesthesia was shorter after IONB in canines (P = .002) and central incisors (P = .022). The incidence of subjective lip numbness was 100 percent after IONB and 14.3 percent after AMSA nerve block (P < .001), with numbness lasting twice as long after IONB (P = .019). The authors noted no significant difference in injection discomfort between the two techniques (P = .768). CONCLUSIONS: The IONB produced anesthetic success in canine and premolar teeth, with a more rapid onset than that for the AMSA nerve block. Although the AMSA technique was significantly more successful than IONB in attaining incisor anesthesia, it was ineffective for central incisors, as assessed according to rigorous electronic pulp testing. The IONB and AMSA nerve block produced similar levels of injection discomfort.

Infiltration anesthesia in the mandible.

Infiltration is preferred to regional block techniques in the maxilla as the former offers a number of advantages. This paper considers the evidence for the efficacy of infiltration anesthesia in the mandible in the adult dentition, both as a primary and as a supplemental method.

Pharmacology and the elderly.

UNLABELLED: This paper describes the impact of ageing on an individual's ability to process drugs. It considers adverse drug reactions in the elderly and discusses prescribing for the older dental patient. CLINICAL RELEVANCE: Many older dental patients will be suffering from medical conditions or taking prescribed or non-prescribed drugs. These can influence the impact of drugs prescribed by dentists.

Effect of time on clinical efficacy of topical anesthesia.

The objective of this study was to determine the effect of time on the clinical efficacy of topical anesthetic in reducing pain from needle insertion alone as well as injection of anesthetic. This was a randomized, double-blind, placebo-controlled, split-mouth, clinical trial which enrolled 90 subjects, equally divided into 3 groups based upon time (2, 5, or 10 minutes) of topical anesthetic (5% lidocaine) application. Each group was further subdivided into 2: needle insertion only in the palate or needle insertion with deposition of anesthetic (0.5 mL 3% mepivacaine plain). Each subject received drug on one side and placebo on the other. Subjects recorded pain on a 100-mm visual analog scale (VAS). The results showed that for needle insertion only, 5% lidocaine reduced pain as determined by a significant difference in mean VAS after 2 minutes (20.1 mm, P < .002), 5 minutes (15.7 mm, P < .022), and 10 minutes (13.7 mm, P < .04), as analyzed by paired t tests. For needle insertion plus injection of local anesthetic, a significant difference in mean VAS was noted only after 10 minutes (14.9 mm, P < .031), yet pain scores for both topical anesthetic and placebo were elevated at this time point resulting in no reduction in actual pain. Time of application did not result in a significant difference in effect for either needle insertion only or needle insertion plus injection of local anesthetic, as analyzed by 1-way analysis of variance (ANOVA). In conclusion, topical anesthetic reduces pain of needle insertion if left on palatal mucosa for 2, 5, or 10 minutes, but has no clinical pain relief for anesthetic injection.

Local anaesthesia: risks and controversies.

UNLABELLED: This paper describes the complications that can occur as the result of the intra-oral injection of local anaesthetics. It considers important localized and systemic complications and describes strategies to limit the occurrence of such problems. CLINICAL RELEVANCE: Local anaesthetics are routinely administered during many dental procedures. An understanding of the risks involved in these injections is important.

Articaine infiltration for anesthesia of mandibular first molars.

A randomized, controlled trial of 31 healthy volunteers compared 4% articaine with 1:100,000 epinephrine buccal infiltration to buccal plus lingual infiltration of the same dose of drug in achieving pulpal anesthesia of mandibular first molar teeth. Data were compared with efficacy of an inferior alveolar nerve block using 2% lidocaine 1:80,000 epinephrine in a cohort of 27 of the volunteers. Anesthesia was determined using electronic pulp testing. Buccal and buccal plus lingual infiltrations of articaine with epinephrine did not differ in efficacy in obtaining pulpal anesthesia for mandibular permanent first molars (p = 0.17). Efficacy of 4% articaine with epinephrine infiltrations for first molar pulp anesthesia was similar to that of an IANB using lidocaine with epinephrine over a 30-minute study period (96 and 80 episodes of no response to maximal stimulation respectively, p = 0.097). Subjective tooth numbness was more common after IANB than buccal infiltration (p = 0.005). The discomfort of buccal infiltration with articaine was volume dependent (p = 0.017) and similar to that of an IANB.

A method for clinically defining "improvers" in chronic pain studies.

AIMS: To test a measurement model based on clinicians' assessments of patient data that allows simple and confident clinical validation of any statistical or numerical technique designed to separate patients improving with treatment from those who are not, particularly for pain that shows large daily variation. METHODS: Diaries using daily visual analog scales (VAS) of pain intensity were obtained from 39 patients treated for chronic temporomandibular disorders. Three experienced clinicians visually assessed 39 VAS/time graphs. Criteria indicating improvement (general trend, height and apparent frequency of graph spikes) evolved over 3 assessments. The third assessment defined improvers visually. Numeric analyses considered the difference between first and last months of treatment for mean, area under the curve (AUC), and maximum VAS scores. Thresholds of 40%, 50%, or 60% pain reduction defined improvement numerically. Aggregate sensitivity and specificity was compared with visual definition to find the optimal threshold. RESULTS: Patients were defined visually as improvers, nonimprovers, and borderline cases. Interexaminer reliability for identifying improvers was good (k = 0.79). Mean VAS and AUC were highly correlated (r = 0.999). The optimal threshold of mean and maximum VAS relative to visual definition was 50% pain reduction. Cases defined as improvers by both mean and maximum agreed best with the visual definition (sensitivity 90%, specificity 84%). CONCLUSION: Visual assessment of VAS demonstrates distinct pain/time patterns that can validate numeric definition of complex pain recovery. No single numeric method can be guaranteed to give a clinically valid outcome.

The effects of antihypertensive medication on dental treatment.

UNLABELLED: Hypertension is a medical problem that impacts on health worldwide. A number of different medications are used to treat hypertension. These drugs can affect the mouth and perioral structures and impact upon dental management. It is therefore important that dentists are aware of the side-effects and relevant drug interactions that occur in patients on antihypertensive medication. CLINICAL RELEVANCE: Dentists will encounter patients receiving antihypertensive therapy and should be aware of how these drugs impact upon dental treatment.

Dental management of patients taking methadone.

Methadone is a synthetic opiate used in the treatment of opiate addiction. Various side-effects have been associated with the use of methadone. These include xerostomia, which can contribute to a high caries rate. The UK Regional Drug Misuse Database reported that around 118,500 drug users were receiving treatment from drug misuse agencies and GPs. The vast majority (87%) were receiving treatment from community specialist services. As many drug abusers have poor oral health, general dental practitioners are likely to encounter such individuals. It is essential therefore that dentists are aware of the potential difficulties that may be encountered when treating subjects receiving methadone. These problems may relate to previous drug abuse and to the effects of methadone therapy.

Injection pain: comparison of three mandibular block techniques and modulation by nitrous oxide:oxygen.

BACKGROUND: The authors conducted this study to compare the pain on injection of the three mandibular block techniques and to determine the effect that the delivery of nitrous oxide:oxygen, or N2O:O2, had on this pain. METHODS: Based on sample size calculation, the authors randomly assigned 60 subjects to receive either local anesthetic alone or local anesthetic with N2O:O2 titrated to effect. Each subject received two mandibular block injections bilaterally from three possible pairings: Gow-Gates/standard block, standard block/Vazirani-Akinosi or Gow-Gates/ Vazirani-Akinosi. Subjects scored their pain using a 100-millimeter visual analog scale immediately after each injection. The authors analyzed data using analysis of variance, Student t tests and multiple regression analyses. RESULTS: There were no significant differences in pain on injection among the three injection techniques. The subjects in the group that received N2O:O2 and the local anesthetic demonstrated a statistically significant reduction in pain on injection compared with subjects in the group that received the local anesthetic only (P < .05). When N2O:O2 was used, there was a statistically significant decrease in pain with the first injection (P < .0005), an effect not seen with the second injection. CONCLUSIONS: There was no significant difference in pain among the three mandibular block techniques. N2O:O2 can reduce pain on the first injection given, but this effect is not seen subsequently. CLINICAL IMPLICATIONS: The decision to select one of the three mandibular block techniques should be based on factors other than pain on injection. N2O:O2 reduces pain on the first injection only.

Effective topical anesthetic agents and techniques.

What conclusions can be drawn concerning intraoral topical anesthesia? First, a variety of agents have been shown to have a pharmacologic effect. When used as a single agent, lidocaine is effective at concentrations between 5% and 20%. There is evidence of a dose response with lidocaine [17]. The combination of 2.5% lidocaine and 2.5% prilocaine has been shown to be a reliable agent; however, at the time of writing, this mixture is not licensed for intraoral use. Benzocaine is effective when used alone at a concentration of 20% and when combined at a dose of 15% with 1.7% amethocaine. Second, a crucial factor governing effectiveness is the time of application. One study cited in this paper [23] has shown an effect occurring in the maxillary buccal sulcus after a 1-minute application. Others [17,25] have shown that a 2- to 3-minute application at the same site is no better than placebo. The differences in these studies may be caused by the use of different test stimuli, such as the gauge of the needle used and the depth of insertion. When applied for 5 minutes, it seems that success is guaranteed when used in the buccal fold of either jaw. Finally, the site of application is important. Palatal mucosa is more resistant to the effects of topical anesthetics than other intraoral sites investigated. There is no evidence that topical anesthetics have any value in reducing the discomfort of deep regional block administrations such as inferior alveolar nerve block injections.