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Biomedical subjects

D R Morse

Publications and source records attributed to D R Morse.

At least 19 recordsLinked to original sources
PubMed1991

Age-related changes of the dental pulp complex and their relationship to systemic aging.

The dental pulp and its associated structures, the dentin and the cementum, are discussed. Because many of the age-related pulpal changes have components considered in several of the current theories of aging, these theories are briefly reviewed. Part 2 describes the age-related changes of the dental pulp, the dentin, and the cementum (the dental pulp complex). An attempt is made to differentiate inherent aging changes from physiologic defensive changes and pathologic irritant-induced changes. Part 3 describes the relationship of age-induced changes in the dental pulp complex to components of the current aging theories together with a unified concept of the dental pulp complex aging. Part 4 considers whether dental pulp complex aging can be used as a biomarker for generalized aging. Whether age-related changes of the dental pulp complex can be altered by interventions is discussed.

Aging↗
PubMed1991

A review of aging of dental components and a retrospective radiographic study of aging of the dental pulp and dentin in normal teeth.

A review of aging of dental components is followed by a clinical radiographic study. Patients received radiographs at 5-year intervals with a 10-year minimum followup. Data obtained were age, gender, tooth, and systemic diseases. Measurements taken were tooth length, coronal length, apical length, cervical width, midroot width, and apical width. Root canal shrinkage was calculated vertically, horizontally, and as a combination (vertical and horizontal). Results showed statistically significantly more shrinkage in men, the elderly, and people with calcification-related diseases. Shrinkage increased with advancing age. With further studies, radiographically determined root canal measurements could prove useful in anthropology, forensics, and as a biomarker of aging.

Adult↗
PubMed1990

The antimicrobial effect of various endodontic sealers.

The antimicrobial activity of an endodontic sealer can be helpful in destroying any remaining root canal microbes. Therefore it was decided to test the antimicrobial activity of several commonly used endodontic sealers. The sealers used were Grossman's sealer, Tubliseal, Calciobiotic, Sealapex, Hypocal, eucapercha, Nogenol, and AH26. Also tested were dry calcium hydroxide powder, calcium hydroxide mixed with saline, and a Teflon formulation. The microbes used were Streptococcus mutans (a gram-positive microaerophile). Staphylococcus aureus (a gram-positive facultative anaerobe), and Bacteroides endodontalis (a gram-negative obligate anaerobe). The freshly mixed sealers were placed into the prepared wells of agar plates inoculated with the test microorganisms. After varying periods of incubation, the zones of inhibition of bacterial growth were observed and measured. Grossman's sealer had the greatest overall antibacterial activity. However, AH26 had the greatest activity against B. endodontalis. The zinc oxide-eugenol-based sealers had more antimicrobial activity than either the calcium hydroxide-based sealers or eucapercha.

Bacteroides↗
PubMed1990

A dentist's dilemma: nonsurgical endodontic therapy or periapical surgery for teeth with apparent pulpal pathosis and an associated periapical radiolucent lesion.

First presented is a brief review of nonsurgical versus surgical treatment of radicular cysts. This is followed by a consideration of the use of radiographs for differential diagnosis of periapical radiolucent lesions. Some of the nonendodontic local and systemic lesions that can occur periapically are then presented. Next examined are the fallibilities of pulp vitality testing methods. The need for histopathologic examination of periapical lesions is the subject of the next discussion. The dentist's dilemma is then examined: should teeth with apparent pulpal pathosis and an associated periapical radiolucent lesion have routine surgical treatment including biopsy or should they be treated nonsurgically and have periodic follow-ups? A possible resolution of this dilemma is the final consideration.

Dental Pulp Diseases↗
PubMed1990

A clarification on endodontic flare-ups.

In an article on endodontic flare-ups by Robert J. Matusow, our research and publications are discussed. Since we found what we consider to be distortions and misinterpretations of our work, it was decided to clarify the apparent discrepancies found in Matusow's article.

Acute Disease↗
PubMed1990

A comparison of erythromycin and cefadroxil in the prevention of flare-ups from asymptomatic teeth with pulpal necrosis and associated periapical pathosis.

In a previous study by our group with patients having asymptomatic teeth with pulpal necrosis and an associated periapical radiolucent lesion (PN/PL), it was shown that prophylactic administration of penicillin V or erythromycin (high-dose, 1-day regimen) resulted in a low incidence of flare-up (mean = 2.2%) and a low incidence of swelling and pain not associated with flare-up. No hypersensitivity responses occurred, and gastrointestinal side effects were found primarily with the erythromycins. To ascertain whether a single-dose administration of a long-acting 1-gm tablet of the cephalosporin antibiotic cefadroxil would result in a similar outcome, the present study was undertaken with 200 patients having quiescent PN/PL. The patients were randomly given either cefadroxil or erythromycin (base or stearate). Evaluations of flare-up were done 1 day, 1 week, and 2 months after endodontic treatment. A 2.0% flare-up incidence was found, with no statistically significant differences for cefadroxil (1.0%), stearate (2.0%), or base (4.0%). No hypersensitivity responses occurred. Gastrointestinal side effects were found primarily with the erythromycins (19.0%). The results showed that a 1-gm, single-dose regimen of cefadroxil was as effective as erythromycin and penicillin in preventing flare-ups and serious sequelae. A comparative analysis of the data from our first study (no peritreatment antibiotics) and the pooled data from our last three investigations (including the current trial) showed that peritreatment antibiotic coverage significantly reduced flare-ups and serious sequelae after endodontic treatment of asymptomatic PN/PL (p less than 0.001).

Acute Disease↗
PubMed1990

Comparison of prophylactic and on-demand diflunisal for pain management of patients having one-visit endodontic therapy.

To determine whether the posttreatment prophylactic use of diflunisal (Dolobid 500) would be more effective than the on-demand use of diflunisal in reducing endodontic posttreatment pain, the current open-label, randomized study was undertaken. After one-visit nonsurgical endodontic therapy, 100 patients with asymptomatic teeth having either vital-inflamed pulp, pulpal necrosis, or pulpal necrosis with periapical radiolucent lesion were randomly given either prophylactic diflunisal (two tablets immediately at the conclusion of the visit, then four tablets to be taken in the schedule of one every 8 to 12 hours for pain if needed) or on-demand diflunisal (same dosage schedule; pills to be taken only if needed). The outcome showed that compared to the on-demand usage, the posttreatment prophylactic administration of diflunisal resulted in a statistically significant reduction in the number of episodes of endodontic posttreatment pain that required analgesic intervention. It appears from the results of this study that the posttreatment prophylactic use of diflunisal is significantly more effective than the on-demand usage of diflunisal in reducing endodontic posttreatment pain for one-visit endodontic therapy with all types of originally asymptomatic endodontic conditions. Further studies are necessary to determine whether pretreatment prophylactic deflunisal would be more effective, and also the effectiveness of prophylactic diflunisal in reducing posttreatment pain in presenting symptomatic cases and for cases treated in multiple visits.

Adolescent↗
PubMed1990

Use of analgesics and antibiotics in endodontics: current concepts.

In this review, the principal drugs used for prevention and treatment of pain--analgesics, and swelling--antibiotics, are examined. The rationale for prevention of pain and swelling is given. Then the specific drugs are considered. The analgesics evaluated include: the non-steroidal anti-inflammatory agents (e.g., aspirin, acetaminophen, ibuprofen, diflunisal); and the narcotics (e.g., codeine, oxycodone, hydrocodone, meperidine). The antibiotics evaluated include: the penicillins (e.g., penicillin V, ampicillin, methicillin); the cephalosporins (e.g., cephalexin, cefadroxil); the erythromycins (e.g., erythromycin stearate, erythromycin base); clindamycin; metronidazole; and some rarely used drugs (e.g., ciprofloxacin).

Analgesics↗
PubMed1990

Apexification: review of the literature.

Five methods for the treatment of teeth with an incompletely formed apex (open apex) and a necrotic pulp are discussed. The methods discussed include the use of (1) a customized cone (blunt-end, rolled cone); (2) a short-fill technique; (3) periapical surgery (with or without a retrograde seal); (4) apexification (apical closure induction); and (5) one-visit apexification. The apexification techniques, which use various formulations of calcium hydroxide to induce closure, are stressed. Based on the review of the literature and clinical experience of the authors, it was concluded that successful treatment of an immature pulpless tooth can partly result from the antibacterial and calcification-inducing action of calcium hydroxide.

Calcium Hydroxide↗
PubMed1990

Management of teeth with open apexes and necrotic pulps: representative cases.

This paper briefly reviews the pros and cons of five methods used to treat a tooth with a necrotic pulp and an open apex (incompletely developed root), and presents representative treatments of open apex cases. These treatments include customized cone, short-fill, periapical surgery, apexification, and one-visit apexification.

Adult↗
PubMed1990

A unified theory of aging.

In the 1988 issue of this Journal, in the article: "Aging: Causes and control," 17 aging theories were presented. Those theories are now amplified, and an additional 7 theories are considered. Utilizing concepts from these theories, a unified theory of aging is then presented.

Adult↗
PubMed1989

A prospective randomized double-blind trial on efficacy of dexamethasone for endodontic interappointment pain in teeth with asymptomatic inflamed pulps.

To determine whether a relatively large dose of oral dexamethasone given for a short period of time would be effective in reducing endodontic interappointment pain, the current double-blind, placebo-controlled study was undertaken. After the visit for instrumentation, 40 patients with asymptomatic teeth having vital-inflamed pulps were randomly given either dexamethasone (3 tablets of 4 mg each) or a dextrose placebo identical in appearance (same dosage schedule). The outcome showed that the oral administration of dexamethasone resulted in a statistically significant reduction in endodontic interappointment pain at all three time periods evaluated, that is, at 8 hours, 24 hours, and 48 hours (p less than 0.01). It appears from the results of this study that this dosage schedule of oral dexamethasone is sufficient to significantly reduce endodontic interappointment pain for teeth with asymptomatic vital-inflamed pulps. Further studies are needed for teeth with other endodontic pulpal-periapical conditions and for symptomatic teeth.

Clinical Trials as Topic↗
PubMed1989

An evaluation of tricalcium phosphate as a treatment for endodontic perforations.

In the rat, perforations of maxillary molars were created and treated with either tricalcium phosphate (Synthograft) or Cavit. At four time intervals (1 day, 1 wk, 2 wk, and 1 month), four evaluative factors (inflammation, bone resorption, cementum and dentin resorption, and epithelial proliferation) were analyzed and compared for the two materials. For the individual time periods, there were no statistically significant differences between the two materials. However, when all four time periods were combined, there was a statistically significant better result for tricalcium phosphate than for Cavit with respect to decreased inflammation (p less than 0.05).

Animals↗
PubMed1989

Oral digestion of a complex-carbohydrate cereal: effects of stress and relaxation on physiological and salivary measures.

A comprehensive study was undertaken with 12 dental hygiene students to ascertain whether the time of chewing or the degree of relaxation is more important in the oral digestion of complex carbohydrates. In addition, we studied whether the effects of stress and relaxation on salivary alpha-amylase activity was corroborated by physiologic measures. The dental hygiene students chewed an oat cereal for either 20 or 60 s while under two different orders of stress and relaxation conditions: 1) stress/20 s, stress/60 s, relax/20 s, relax/60 s; and 2) relax/20 s, relax/60 s, stress/20 s, stress/60 s. Galvanic skin resistance, pulse rate, and blood pressure (systolic and diastolic) were used to physiologically verify the effects of stress and relaxation on amylase activity. Amylase activity was judged by spectrophotometric analysis of maltose produced from a specific dilution of expectorated saliva. Results showed that the physiological measures significantly corroborated the salivary determinations of stress and relaxation and that deep relaxation was significantly more important than thorough chewing in the oral digestion of complex carbohydrates.

Adult↗
PubMed1988

A prospective randomized trial on efficacy of antibiotic prophylaxis in asymptomatic teeth with pulpal necrosis and associated periapical pathosis.

A recent study from a private endodontic practice compared "prophylactic" antibiotic (high-dose, 1-day) regimens of penicillin V and erythromycin (base or stearate) for patients who had asymptomatic teeth with pulpal necrosis and associated periapical radiolucent lesions (PN/PL). A 2.2% flare-up incidence was found, with no statistically significant differences for penicillin (0.0%), base (2.9%), and stearate (3.8%). No hypersensitivity responses occurred, and gastrointestinal side effects were found primarily with the erythromycins (12.4%). To ascertain whether or not similar results would occur with student operators in a dental school clinic population, the current study was undertaken. One-hundred ninety-five patients with quiescent PN/PL were randomly given either penicillin V or erythromycin (base or stearate). A 2.6% flare-up incidence was found, with no statistically significant differences for penicillin (3.1%), base (1.5%), and stearate (3.1%). No hypersensitivity responses occurred, and GI side effects were found primarily with the erythromycins (17.7%). As can be seen, the results were very similar to those of the recent endodontic practice study. Hence, it can be concluded that the results of the previous endodontic practice study were not unique to any one clinician or method. A comparison was also made between the "prophylactic" penicillin group of the current study and the placebo control group of our previous dental school clinic, student operator study (in which the methods, population, and regimen were almost identical to those of the current study). The results showed that the "prophylactic" penicillin group had significant fewer flare-ups and non-flare-up-associated swelling and pain than did the placebo group. In view of these findings and those from studies from the literature in which "prophylactic" antibiotics were not used, it is our opinion that the antibiotic regimens used in the current study should be a component of clinical endodontic therapy for quiescent PN/PL.

Adolescent↗
PubMed1988

A comparative tissue toxicity evaluation of established and newer root canal sealers.

Grossman's sealer, eucapercha, Endo-Fill, CRCS, Sealapex, Hypocal, and sterile saline solution (0.3 ml of each) were injected into specific dorsal subdermal tissue sites of 12 guinea pigs. The animals were killed after 6 days, 15 days, and 80 days (four per time period). Analysis of tissue response showed that, overall, Sealapex and Endo-Fill had less severe inflammatory reactions than any of the other test materials. Grossman's sealer, CRCS, and Hypocal showed principally severe inflammatory responses at both 6 and 15 days, but mild reactions at 80 days. Overall, eucapercha showed less severe inflammatory responses than Grossman's sealer, CRCS, and Hypocal. Diffuse calcification was induced by the three calcium hydroxide preparations (CRCS, Sealapex, and Hypocal). Eucapercha and Endo-Fill had minute local areas of calcification. Both Grossman's sealer and CRCS did not have overall favorable histologic reactions; however, Grossman's sealer and CRCS have been used successfully clinically. Further clinical studies are needed.

Animals↗