Effects of gastroesophageal reflux on the oral cavity.

The effects of chronic exposure of the oral cavity to gastric acid can be many and varied. Soft tissue symptoms (nonspecific burning and sensitivity) have been mentioned in the literature, but pathognomonic soft tissue lesions have not been documented. Dental erosion can be considered to be the predominant oral manifestation of gastroesophageal reflux disease. Erosion begins with subtle changes in the surface enamel and can progress to severe loss of tooth substance. Because the causes of such tooth lesions may be multifactorial, combining the effects of erosion, attrition, and abrasion and because of the subtle changes present in the beginning stages of such lesions, diagnosis may be difficult. Although the basic mechanism of erosion in gastroesophageal reflux patients is the dissolution of enamel and dentin due to acid exposure, a multitude of other factors can modify the effects of gastric acid. Salivary parameters, in particular, may play an important role in affecting oral pH after reflux episodes. Once dental erosion is diagnosed, thorough evaluation is necessary to document the extent of damage and to detect a cause, which may have both intrinsic and extrinsic components. Treatment goals include eliminating the causes of acid exposure, preventing the effects of acid exposure when it is not controllable, treating symptoms of soft tissue irritation and dental erosion, and restoring the dentition to an esthetically and functionally acceptable level.

Dental evaluation in bone marrow transplantation.

In the case presented, thorough radiographic and clinical examinations would have precluded misinforming the patient and prevented a six-week delay of the bone marrow transplant. The patient's ill feeling was generated because of confusion about the recommended dental treatment. This was unfortunate, given the considerable physical and emotional stress that these patients endure under the best of circumstances. Because of the severity of immunosuppression before and (for three months) after transplantation, and the life-threatening nature of oral infection, elimination of oral infection is paramount for successful BMT. This can only be achieved by adequate diagnosis and prompt, aggressive dental treatment.

Dental erosion and acid reflux disease.

OBJECTIVE: To determine the relation between gastroesophageal reflux disease and dental erosion using ambulatory 24-hour esophageal pH testing. DESIGN: Cross-sectional observational study. SETTING: Tertiary referral center. PATIENTS: The dental group consisted of 12 patients with idiopathic dental erosion who were identified by dentists and screened for gastroesophageal reflux disease using 24-hour pH testing. The gastroenterology group consisted of 30 patients who had 24-hour pH testing in the esophageal laboratory and who were referred for dental evaluation (10 did not have reflux, 10 had distal reflux, and 10 had proximal reflux). MEASUREMENTS: 24-hour esophageal pH monitoring using a pH probe in the distal and proximal esophagus. Complete dental examination with particular attention to the presence and severity of dental erosion; plaque; gingival damage; and decayed, missing, and filled teeth. Analysis of saliva for pH, flow rates, buffering capacity, and calcium and phosphorus levels. Standardized questionnaire to ascertain possible causes of dental erosion and presence of reflux symptoms. RESULTS: Ten of the 12 patients in the dental group (83% [95% CI, 52% to 98%]) had gastroesophageal reflux on esophageal pH monitoring. Nine had distal and 7 had proximal reflux. Seven had reflux in the upright position only, 1 had reflux in the supine position only, and 2 had both upright and supine reflux. No saliva abnormalities were found. Ten patients had typical symptoms of gastroesophageal reflux, but dietary or mechanical problems that may have been causing dental erosion were not identified. In the gastroenterology group, upright reflux was seen in 5 of the 10 patients with distal reflux and in all 10 patients with proximal reflux. In addition, 40% of patients in the gastroenterology group (12 of 30) had dental erosion (4 of the 10 with distal reflux [40%], 7 of the 10 with proximal reflux [70%], and only 1 of the 10 without reflux [10%]; P = 0.02 for those with reflux compared with those without reflux). The cumulative dental erosion score correlated with proximal upright reflux when all 24 study patients with erosion were analyzed (r = 0.55 [P < 0.01]); this correlation was even stronger in the subgroup of 12 patients with abnormal amounts of proximal upright reflux (r = 0.84 [P = 0.001]). CONCLUSION: Dental erosion is a common finding in patients with gastroesophageal reflux disease and should be considered an atypical manifestation of this disease.

Radiographic evaluation of occlusal caries: effect of training and experience.

The purpose of this study was to investigate what effect differing levels of didactic education and clinical experience have on the ability to diagnose occlusal caries from radiographs. Freshman and senior dental students and dental school faculty were asked to evaluate bitewing radiographs for the presence of occlusal caries and for a recommendation for restorative treatment. The agreement between histologic and radiographic diagnosis was assessed by calculating sensitivity, specificity, accuracy, and interexaminer agreement. It was concluded that dental students and faculty did differ in their abilities to evaluate radiographs for occlusal caries, and that education and clinical experience especially affected interexaminer agreement.

Shear bond strengths of composite to chlorhexidine-treated enamel.

This study determined the shear bond strength (SBS) of composite bonded to chlorhexidine-treated enamel and untreated enamel. Fifty human molars were mounted in cold- cure acrylic and the superficial enamel of the buccal or lingual surface was exposed using 600-grit silicon carbide paper. During the experimental protocol, the control group (n = 25) and the experimental group (n = 25) were stored in distilled water at 37 degrees C. The experimental group was immersed in 0.12% chlorhexidine gluconate for 1 minute, 4 times daily, for 7 days. Prisma APH composite was then bonded to all samples following acid etching for 30 seconds, and the SBS was determined. Shear bond strengths for the control (13.23 +/- 3.22 MPa) and the experimental (13.67 +/- 4.59 MPa) groups were not significantly different using a t-test. The result may be attributed to either a lack of effect of chlorhexidine or to the acid etch which dissolves the affected superficial enamel leaving an unaffected substrate for bonding.

Tooth erosion: an unusual case.

A case of tooth erosion due to prolonged exposure to acidic pool water has been presented. Dentists and swimmers must be aware of the detrimental dental effects associated with prolonged exposure to improperly maintained pool water, and what measures can be taken to prevent such effects.

Effect of immune bovine milk on Streptococcus mutans in human dental plaque.

The use of a mouthrinse of bovine milk containing antibodies to Streptococcus mutans resulted in an initial reduction in the numbers of recoverable Strep. mutans in a group of 9 individuals. Ten volunteers who used control bovine milk that contained no antibody activity to Strep. mutans had variable levels of plaque Strep. mutans. In addition, after culture on Mitis Salivarius and Gold's agar, the plaque Strep. mutans from subjects who used the immune bovine milk rinse formed smaller colonies than those from pre-treatment plaque and from all plaque samples of subjects who used the control rinse.

Function of anti-Streptococcus mutans antibodies: inhibition of virulence factors and enzyme neutralization.

The levels of parotid salivary IgA and serum IgG antibodies from dental caries-resistant (CR) and caries-susceptible (CS) individuals to Streptococcus mutans antigens were determined. In general, the levels of salivary IgA and serum IgG antibodies to S. mutans antigens were significantly higher in CR subjects than in CS individuals. There were significantly higher levels of IgA2, but not IgA1, salivary antibodies to S. mutans whole cells in CR subjects than in CS individuals. These results led us to investigate the functional effects parotid saliva and sera containing these antibodies had on several factors associated with S. mutans virulence. Parotid saliva and sera from CR subjects significantly inhibited S. mutans growth, adherence, acid production, glucosyltransferase and glucose-phosphotransferase activities to a greater extent than saliva and sera from CS individuals. The data suggest that neutralization of S. mutans enzymes and inhibition of S. mutans virulence factors by saliva and serum may be responsible for the lower numbers of carious lesions in CR subjects.

Protective secretory immunoglobulin A antibodies in humans following oral immunization with Streptococcus mutans.

Ingestion of a vaccine containing killed Streptococcus mutans, originally isolated from each volunteer, daily for 10 consecutive days induced increased levels of specific secretory immunoglobulin A (sIgA) antibodies to S. mutans cells and two cell surface proteins, glucosyltransferase and surface antigen I/II, in parotid saliva and tears of four healthy males and in parotid saliva, tears, colostrum, and milk of a pregnant woman. In addition, these antibodies inhibited glucosyltransferase activity. Both IgA1 and IgA2 antibodies were induced. The levels of IgA antibodies in all secretions remained significantly above preimmunization levels for more than 50 days after oral administration of antigen. A second series of immunizations for 7 consecutive days resulted in even higher levels of sIgA antibodies, which peaked earlier and persisted longer than those observed after the primary immunizations. No increase in levels of antibodies in serum were detected in any subject. Antibodies reactive with human heart and kidney antigens could not be detected in saliva, tears, colostrum, milk, or serum samples collected at any time during the immunization regimen. The numbers of viable S. mutans organisms in dental plaque and whole saliva decreased after each series of immunizations, which correlated with increased levels of IgA antibodies in saliva, suggesting that IgA antibodies in saliva were responsible for the reduced adherence of this bacterium. These results indicate that ingested S. mutans antigen induces secretion of specific IgA1 and IgA2 antibodies in saliva, tears, colostrum, and milk, providing further evidence for the existence of a common mucosal immune system.

Protection of gnotobiotic rats against dental caries by passive immunization with bovine milk antibodies to Streptococcus mutans.

A multivalent vaccine consisting of whole cell antigens of seven strains, representing four serotypes (b, c, d and g), of mutans streptococci was used to hyperimmunize a group of cows. Serum samples from these animals contained immunoglobulin G1 (IgG1) antibody activity to seven serotypes (a to g) of mutans streptococci. Whey obtained from the animal with the highest serum antibody activity, which also contained high levels of IgG1 antibody, was used in passive caries immunity studies. Gnotobiotic rats monoinfected with Streptococcus mutans MT8148 serotype c or Streptococcus sobrinus OMZ176 (d) or 6715 (g) and provided a caries-promoting diet containing immune whey had lower plaque scores, numbers of streptococci in plaque, and degree of caries activity than similarly infected animals given a diet containing control whey obtained from nonimmunized cows. To establish the nature of the protective component(s) present in the immune whey, an ultrafiltrate fraction of the whey was prepared. This preparation contained higher levels of IgG1 anti-S. mutans antibody activity than the immune whey. Rats monoinfected with S. mutans MT8148 and provided with a diet supplemented with 0.1% of this fraction exhibited a degree of caries protection similar to that seen in animals provided a diet containing 100% immune whey. In fact, a diet containing as little as 0.01% of the ultrafiltrate fraction gave some degree of protection against oral S. mutans infection. The active component in the immune whey was the IgG1 anti-S. mutans antibody, since rats monoinfected with S. mutans MT8148 and provided a diet supplemented with purified immune whey IgG1 had significantly reduced plaque scores, numbers of S. mutans in plaque, and caries activity compared with control animals. Prior adsorption of the IgG fraction with killed S. mutans MT8148 whole cells removed antibody activity and abrogated caries protection.

Salivary immunoglobulin A and serum antibodies to Streptococcus mutans ribosomal preparations in dental caries-free and caries-susceptible human subjects.

Caries-free subjects or individuals with low caries susceptibility exhibited significantly higher (P less than 0.001) levels of naturally occurring salivary immunoglobulin A (IgA) and serum IgG, IgA, and IgM antibodies to a Streptococcus mutans ribosomal preparation than subjects with high caries susceptibility. Absorption of saliva and serum samples with S. mutans ribosomal preparations, but not with other S. mutans antigens or with Escherichia coli and Neisseria gonorrhoeae ribosomal preparations, removed the antibody activity. Absorption with Streptococcus sanguis ribosomes and NH4Cl-washed S. mutans ribosomes partially removed the anti-S. mutans ribosome antibody activity. These results provide evidence that naturally occurring salivary and serum antibodies to the S. mutans ribosomal preparation correlate with susceptibility to dental caries.

Tooth extraction by orthodontic force after radiation therapy: report of case.

This report presents a therapeutic approach to orthodontic tooth extraction in a patient at high risk for the development of osteoradionecrosis with conventional techniques. The rationale for this procedure is discussed in detail, combining principles of radiation biology, clinical radiation therapy, and biomechanics of tooth movement.

Prevention of Streptococcus mutans colonization by salivary IgA antibodies.

The levels of salivary and serum IgA, IgG, and IgM antibodies to the seven serotypes (a-g) of Streptococcus mutans were established in 12 laboratory volunteers using a sensitive enzyme-linked immunosorbent assay. Salivary IgA antibody levels to the serotype c organism were significantly lower (P less than 0.005) than antibody levels to the other six serotypes of S. mutans. Similar results were found with a purified S. mutans serotype c carbohydrate. Serum IgG and IgM antibody titers to the serotype c whole cells were significantly higher (P less than 0.05) than to four other S. mutans serotypes (a, e-g). The abilities of S. mutans serotypes c and d to colonize molar tooth surfaces were examined in eight volunteers. S. mutans serotype d was cleared from the tooth surfaces within 24 hr of challenge, whereas S. mutans serotype c was detected in six of the eight volunteers after 2 weeks and in three of eight after 3 weeks. These results provide additional evidence for the role of salivary IgA antibodies in regulating S. mutans infection and suggest that the low levels of salivary IgA antibodies to S. mutans serotype c may contribute to the predominance of this serotype in the U.S. population.