Comparing efficacy and safety of four intravenous sedation regimens in dental outpatients.

BACKGROUND: Management of patients' fear and anxiety during dental treatment is a primary concern of dental practitioners. Pharmacological strategies used in outpatient dental settings must be both safe and effective. Regimens of intravenously administered sedative drugs were evaluated in a collaborative, multicenter study of outpatients undergoing removal of impacted third molars. METHODS: A total of 997 patients randomly received one of five treatments: placebo; midazolam administered to a clinical endpoint of conscious sedation (mean dose, 8.6 milligrams); midazolam plus additional midazolam as needed during the procedure (mean total dose, 12.2 mg); fentanyl (1.4 micrograms/kilogram) plus midazolam to achieve the same endpoint of conscious sedation (mean dose, 5.7 mg); or fentanyl (1.4 (micrograms/kg), midazolam (mean dose, 5.8 mg) and methohexital as needed during the procedure (mean dose, 61.0 mg). RESULTS: Each drug regimen reduced anxiety during surgery in comparison with placebo, with the combination of midazolam, fentanyl and methohexital resulting in significantly less anxiety in comparison with the other treatment groups. Pain reports by patients during surgery also were reduced significantly by the combination of fentanyl, midazolam and methohexital. Patients' global evaluations of the efficacy of sedation ranked midazolam with supplemental midazolam and the combination of fentanyl, midazolam and methohexital as significantly more efficacious than the other two drug regiments. The authors noted transient respiratory depression in patients in the two opioid-treated groups, but no other physiological changes were detected. CONCLUSIONS: These data provide evidence that the drugs and doses evaluated resulted in therapeutic benefit to dental outpatients, with minimal incidence of potentially serious adverse effects. CLINICAL IMPLICATIONS: The results of this large-scale study provide assurance to both the public and the dental profession of the safety of parenteral sedation with these drugs and combinations of these drugs when titrated slowly in the recommended doses by appropriately trained dentists.

Lingual flap retraction and prevention of lingual nerve damage associated with third molar surgery: a systematic review of the literature.

OBJECTIVE: Lingual nerve damage sometimes occurs after the removal of third molars. The use of a lingual retractor has been advocated to protect the lingual nerve. A systematic review of the literature was undertaken to evaluate the incidence of lingual nerve damage after third molar surgery and the effect of a lingual retractor on nerve damage. STUDY DESIGN: An exhaustive computerized search of several databases and references cited in the various studies was performed. Predetermined inclusion and exclusion criteria were used to identify the 8 published studies acceptable for detailed analysis. The incidence and spontaneous recovery of lingual nerve injury for the following 3 surgical techniques were evaluated: the buccal approach with lingual flap retraction (BA+), or the buccal approach without lingual flap retraction (BA-), and the lingual split technique with lingual flap retraction (LS). RESULTS: In the 8 selected articles, lingual nerve injury occurred in 9.6%, 6.4%, and 0.6% of the pooled LS, BA+, and BA- procedures, respectively. On the basis of risk ratios comparing combined incidence rates, lingual nerve injury is 8.8 times more likely to occur in BA+ than in BA- procedures (CI = 4.3-17.8), 13.3 times more likely to occur in LS than in BA- procedures (CI = 6.6-26.9), and 1.5 times more likely to occur in LS than in BA+ procedures (CI = 1.2-1.8). Permanent lingual nerve injury occurred in 0.1%, 0.6%, and 0.2% of the combined LS, BA+, and BA- procedures, respectively. The combined permanent incidence risk ratios were not calculated because of the low permanent incidence rates. CONCLUSIONS: The use of a lingual nerve retractor during third molar surgery was associated with an increased incidence of temporary nerve damage and was neither protective nor detrimental with respect to the incidence of permanent nerve damage.

Survival of hydroxyapatite-coated implants: a meta-analytic review.

PURPOSE: Some reports show a benefit of coating dental implants with hydroxyapatite (HA), and others assert that resorption of the HA coating compromises long-term implant survival. This study examined this controversy by systematically reviewing all the current literature that reports the outcomes of HA-coated implants in human clinical trials. MATERIALS AND METHODS: A systematic Medline computer search of the English literature yielded 45 human clinical trials that reported on the outcome of HA-coated implants. Eleven studies that met specific inclusion criteria were selected for detailed analysis. The studies were divided into 2 groups. One group of 5 studies reported implant survival using overall percentage, and another group of 6 studies reported implant survival using life-table analysis. RESULTS: The overall percentage survival rates ranged from 93.2% to 98.5%, with 4 to 8 years of follow-up. The cumulative survival rates for studies that used life-table analysis ranged from 79.2% to 98.5%, with 5 to 8 years of follow-up. The yearly interval survival rates reported for the studies using life-tables were variable but remained above 90% and did not show a progressive or precipitous decrease with increasing years of follow-up. CONCLUSIONS: The survival rates reported for HA-coated implants were similar to the survival rates reported for uncoated titanium implants. If resorption of the HA coating causes late failure of implants, the yearly interval survival rates should have decreased with increased years of follow-up. This decrease was not observed in the longitudinal human clinical trials that met the selection criteria for this study. Detailed analysis of these clinical trials did not show that HA-coating compromises the long-term survival of dental implants.

Venous cannulation and topical ethyl chloride in patients receiving nitrous oxide.

The purpose of this study was to evaluate the effect of ethyl chloride spray on the anxiety and pain associated with placing an intravenous catheter in patients sedated with nitrous oxide. Eighty-eight patients scheduled for dental surgery with a combination of intravenous and nitrous oxide sedation were randomly assigned to have ethyl chloride spray or a placebo, water spray, applied before cannulation of a vein. Anxiety and pain were reported using a 10.0-cm visual analog scale before nitrous oxide administration, after nitrous oxide sedation, following application of the spray, and following venous cannulation. The first 2 assessments measured overall levels of patient anxiety and pain and confirmed that nitrous oxide sedation reduced anxiety without changing already low levels of pain. The second 2 assessments of anxiety and pain measured the reaction toward the spray and cannulation. The application of ethyl chloride spray produced significantly more anxiety and pain than did the placebo. The results of this study demonstrate that ethyl chloride spray does not significantly reduce the anxiety and pain associated with venous cannulation in patients sedated with nitrous oxide.

A review of survival rates for implants placed in grafted maxillary sinuses using meta-analysis.

A variety of materials and procedures are used to create adequate bone volume in the maxillary sinus for placement of endosseous implants in the posterior atrophic maxilla. This review used the structured method of meta-analysis to evaluate the survival of the implants placed into various materials that have been used in the maxillary sinus with the sinus lift procedure. A MEDLINE computer search of the English literature yielded 28 studies that reported using the maxillary sinus augmentation procedure to increase bone volume for placement of endosseous implants; only 10 of these met the inclusion criteria for meta-analysis. Data regarding immediate or delayed placement of implants were combined to simplify analysis. Implant survival was 90% for autogenous bone (484 implants in 130 patients followed for 6 to 60 months), 94% for the combination of hydroxyapatite (HA) and autogenous bone (363 implants in 104 patients followed for 18 months), 98% for the combination of demineralized freeze-dried bone (DFDB) and HA (215 implants in 50 patients followed for 7 to 60 months), and 87% for HA alone (30 implants in 11 patients followed for 18 months). The results for autogenous bone were based on six reports, for the combination of autogenous bone and HA on three reports, and for DFDB/HA and HA alone on one study each. The results of single studies cannot be weighted as heavily as the results combining several studies; however, the analysis of these studies suggests that implant survival rates were similar for autogenous bone, HA/autogenous bone mix, HA/DFDB, and HA alone.

Surgical management of patients on warfarin sodium.

PURPOSE: Management of anticoagulated patients has changed significantly over the past 10 years. The change occurred after the introduction of the international normalized ratio (INR) in 1983. This method of reporting prothrombin time for anticoagulated patients has resulted in a decrease in the level at which hematologists and cardiologists keep their patients anticoagulated. Currently, patients are anticoagulated less for the successful prevention of thromboemboli. Recent recommendations are to keep patients anticoagulated to an INR no greater than 3.5. It has been proposed that the extraction of teeth can be performed with INRs of 4 or less. Therefore, the current trend is to maintain patients on their anticoagulation regimens without altering their warfarin dosages. CONCLUSION: With proper local measures, teeth can be extracted safely and the development of thromboemboli in high-risk patients can still be prevented. However, with procedures having a high risk of bleeding, warfarin dosage may need to be modified.

Undergraduate education in implant dentistry.

A special interest group meeting devoted to clinical educational programs in implant dentistry for undergraduate students was held in March 1994 at the annual session of the American Association of Dental Schools in Seattle, Washington. Summaries of the presentations of representatives from three United States dental schools and the moderator's introductory remarks are included in this article.

The anxiolytic effects of intravenous sedation using midazolam alone or in multiple drug techniques.

This study examines four drug combinations (midazolam, midazolam-midazolam, fentanyl-midazolam, and fentanyl-midazolam-methohexital) in a placebo-controlled double-blind clinical trial of intravenous sedation. It tests the hypothesis that there is no difference between the anxiolytic effect of the four combinations when compared with a saline placebo. Subjects were 207 mildly anxious young adults having their third molars removed. Cognitive measures of anxiety increased from preoperative levels in the placebo and both midazolam groups (P < .05). The anxiety response remained the same in the fentanyl-midazolam and fentanyl-midazolam-methohexital groups (P > .05). The level of successful anxiolysis ranged from 24% in the placebo group to 74% in the barbiturate group. Using the log likelihood method, comparisons suggest that the drug groups (from midazolam alone to the methohexital combination) have increasingly positive anxiolytic effects even when controlling for the effects of dental fear and intraoperative pain. The fentanyl-midazolam group is 8.1 and the methohexital group is 9.0 times more likely to have had a favorable outcome than the placebo group. Additional analyses of behavioral measures of anxiety yielded parallel results. Global evaluations after surgery were related to the success of anxiolysis for subjects in the active drug conditions (P < .05).

The safety and efficacy of outpatient midazolam intravenous sedation for oral surgery with and without fentanyl.

This study examined midazolam and midazolam plus fentanyl in a placebo-controlled, double-blind clinical trial. It tested the hypothesis that combined drug therapy results in significantly poorer safety but no difference in efficacy compared to the single drug approach. Subjects were among 207 mildly anxious young adults having their third molars removed. Fentanyl had a significant depressant effect on respiration. Fifty of 79 (63%) subjects who received a midazolam-fentanyl combination became apneic, while only two of 78 (3%) who received midazolam alone were apneic (Fisher's Exact Test, P < 0.001). Two subjects (2.5%) in the combination group and none in the midazolam alone group had oxygen saturations drop below 90%. About twice as many subjects in the combination group had end-tidal carbon dioxide (EtCO2) levels greater than 25% above baseline. While these results are consistent with those for apnea, contingency analyses of the oxygen saturation and EtCO2 results were not statistically significant. Subjects in the combination group were more than four times as likely to have excellent versus good, fair, or poor sedation at a given level of intraoperative pain, and behavioral (movement and verbalization) but not cognitive measures of anxiety were attenuated.

Histologic evaluation of hydroxylapatite-coated versus uncoated titanium blade implants in delayed and immediately loaded applications.

It has been suggested that the long-term success of blade implants could be improved by placing the implants using a two-stage surgical protocol to allow the implant to develop a direct bony interface instead of a fibrous tissue interface. This study compared the implant interfaces of delayed and immediately loaded blade implants in nonhuman primates. A second objective was to compare the effects of hydroxylapatite coating on delayed and immediate loading applications. The delayed loaded uncoated titanium and hydroxylapatite-coated blade implants did osseointegrate. This study also suggests that hydroxylapatite-coated blade implants may form a direct bony interface even when they are loaded immediately after implantation, provided that they are splinted to a firm natural tooth.

Osseointegration of two types of implants in nonhuman primates.

Branemark developed a dental implant that can reliably replace missing teeth. The success of this implant is attributed to a direct connection of bone with the implant (osseointegration). Several implants, including the Core-Vent implant, adhere to the requirements described by Branemark and his coworkers to achieve osseointegration, yet no studies have attempted to directly compare osseointegration of the Biotes implant with other implants. This study directly compared the response of bone to the unloaded and occlusally loaded Core-Vent and Biotes implants at the light microscopic level by using the nonhuman primate model. Histologic examination revealed that both Core-Vent and Biotes implants achieved osseointegration and maintained the direct contact with bone after 5 months of occlusal loading.

Long-standing mandibular dislocation: report of a case.

This report describes a rare case of long-standing mandibular dislocation and its treatment by condylectomy, coronoidectomy, and suprahyoid myotomy.

Effect of hydroxylapatite, tricalcium phosphate, and collagen on the healing of defects in the rat mandible.

The effects of hydroxylapatite and tricalcium phosphate alone or mixed with collagen on the repair of surgically created bony defects in the mandible of 30 rats were evaluated by gross examination and light microscopy. When specimens were examined 4 and 12 weeks after placement of the implants, bone was observed in direct contact with the implants at the periphery; however, in the central portion of the defects, the implants were surrounded by fibrous connective tissue containing macrophages and a few multinucleated giant cells. Neither the hydroxylapatite or the tricalcium phosphate induced bony healing in the defect, and the addition of collagen did not interfere with healing. Because collagen does not alter healing, it might be possible to use it as biocompatible resorbable binder to confine particulate ceramic implants and inhibit their migration.

Autogenous bone grafts for atrophic edentulous mandibles: a final report.

While autogenous bone augmentations for atrophic edentulous mandibles are not the ideal solution for this problem, we do not share the pessimism of other investigators. The average loss of bone over the 92-month observation period was 60% for this small sample of eight patients. However, there was an 81% gain in bone height in the premolar-molar regions when compared with presurgical measurements. Seven of the eight patients believed these procedures were beneficial.

Comparison of complications after bone removal from lateral and medial plates of the anterior ilium for mandibular augmentation.

6 patients whose mandibles were to be augmented with autogenous bone were divided into 2 groups of 3 patients each. In one group, autogenous donor bone was harvested from the medial plate of the anterior ilium, whereas in the second group bone was harvested from the lateral plate. Although some clinicians have asserted that there is less morbidity when bone is harvested from the medial plate, no difference between the 2 groups was noted in the length of hospitalization, amount of blood loss during surgery, incidence of seroma development, or need for a cane or walker. The decision to remove bone from the lateral or medial plates should be based on surgical access rather than incidence of complications.

Viability of the retained bone core in the core-vent dental implant.

The survival of dental implants has been correlated with the formation of a bone-implant interface. This study was done to determine whether the recently developed Core-Vent dental implant forms a bone-implant interface without intervening fibrous tissue. Core-Vent implants were placed in four dogs, and healing was evaluated histologically 15, 30, 60, and 120 days after insertion. Bone grew through the implant vents to join with the inner bone plug, and the implants approximated the bone without an intervening fibrous tissue layer.