permanent teeth were selected in order to ensure an even distribution of multi-rooted teeth. The skulls presented little or no caries, thus eliminating the possibility of a furcation involvement occurring as a result of pulpal disease extending into a furca via an accessory root canal. The exact location of each furcation involvement was recorded, providing the necessary data for determin ing the incidence and distribution of furcal lesions for each age group. It was also determined whether the furcal surface or surfaces denuded as a result of perio dontal disease were located closer to the cemento enamel junction than the noninvolved surface(s). This was ac complished by gently lifting the involved tooth from the socket and measuring the distance between the curve of the denuded furca and the cemento enamel junction versus the distance between the curve of the noninvolved surfaces(s) of the furca and the cemento enamel junction. All measurements were made using a Boley gauge. Masters has suggested that cervical enamel projec tions occurring in molar furcations may be a contributing factor in the development of isolated furcation involve ments. Therefore the number of teeth exhibiting furca tion involvements with cervical enamel projections were also recorded.
Some Anatomical Factors Related to Furcation Involvements
7
by D.
C . LARATO, B.A., D . D . S . ,
M.S.D.*
THE TERM "furcation involvement" refers to the exten sion of pocket formation into the interradicular area of bone of multi-rooted teeth. In the past, teeth with furcation involvements were given a poor prognosis. New concepts of periodontal therapy have now provided dentists with the means to treat such teeth, enabling them to be retained with a good prognosis. Because the treatment of the furcal lesion requires an understanding of the actual disease process involved, it behooves the dentist to know as much as possible about the nature of furcation involvements. In an earlier study by this author, using dry human skull specimens, it was found that the average number of furcation involvements per skull increased with age, and that the first permanent molars most often exhibited denudation of the furca as a result of periodontal disease. The incidence of furcal disease was also found to be related to the length of time the tooth was present in the oral cavity. In addition, the more posterior the position of the tooth in the dental arch, the less the chance the tooth would develop a furcation involvement. It was also observed that in the maxilla and mandible, the buccal aspects of molar furcations were most often denuded as a result of periodontal disease. In the maxilla the second most commonly involved surface was the mesial surface of the furcation. Of all multi-rooted teeth, the maxillary first bicuspids had the lowest incidence of furcation involvements. As a result of these findings, a study was designed to determine whether the position of the root furcation in relation to the cemento enamel junction influences the location of furcation involvements. 1
2-6
8
6
RESULTS
Of a total of 188 furcation involvements, 142 (75%) of the involved furcations were located closer to the ce mento enamel junction than the noninvolved root sur faces (Table 1). In the maxilla 65%, and in the mandible 85% of the root surfaces exhibiting a furcation involve ment were located nearer to the cemento enamel junc tion of the tooth than the noninvolved root surface(s) (Table 2). Of the 188 teeth with furcation involvements only 24 (13%) exhibited cervical enamel projections. DISCUSSION
The high percentage of furcation involvements found associated with a close proximity of the furca to the cemento enamel junction, suggests that the furcal surface closest to the cemento enamel junction of the tooth is the area most susceptible to bone denudation as a result of periodontal disease. A question arises however, as to why the furcal area closest to the cemento enamel junction is most often involved, when bone destruction from perio dontal disease often exhibits an uneven pattern of bone loss. Masters examined a total of 474 extracted permanent maxillary and mandibular molar teeth for the presence of cervical enamel projections. N o attempt was made to select teeth extracted specifically because of periodontal disease. He felt, that when a projection of enamel extended into a root bifurcation, there could be no true fibrous attachment of the periodontal ligament, but rather an attachment of cervicular epithelium to the enamel projection. Such an arrangement he suggested, was highly susceptible to pocket formation in the pres-
MATERIAL AND METHODS
The experimental sample consisted of the same 305 dry human skull specimens of Mexican origin used in the prior study.f Information concerning the age and sex of the skulls was not available, therefore the age of each specimen could only be estimated by the degree of suture closure. The skulls were divided into four approximate age groups as shown in Table 1. Only skulls having 32
9
* Veterans Administration Hospital, Denver, Colorado. t Skulls obtained from the Atkinson Museum of Applied Anatomy School of Applied Anatomy School of Dentistry, University of the Pacific, San Francisco, Calif.
608
Volume 46 Number 10
Anatomical
Total N o . of Skulls Examined
No. of Furcation Involvements
No. of Furcation Involvements Related to the Closeness of the Furca to C E Junction
17-29 yrs.
40
2
2
30-44 yrs. 45-59 yrs. 60 yrs.
59 84 122
22 49 115
17 39 84
Total
305
188
142
(100%)
SUMMARY
A total of 305 dry human skull specimens were examined for the presence of furcation involvements. Of a total of 188 furcation involvements, 142 (75%) were related to the close proximity of the furcation to the cemento enamel junction of the tooth.
(75%)
TABLE 2. Number of Furcation Involvements Related to the Proximity of the Furca to the Cemento EnamelJ unction {Maxilla and Mandible) No. of Furcation No. of Furcation Involvements in 305 Skulls
Involvements Related to the Closeness of the Furca to C E Junction
Maxilla
99
65
Mandible
89
77
188
142
Junction
Total
ence of even slight gingival inflammation. He found that 24% of the 474 teeth he examined had cervical enamel projections, and preliminary clinical findings made by him indicated that enamel projections were found in more than 90% of the isolated periodontal involvements of mandibular root bifurcations. In this author's study only 24 (13%) of the 188 teeth
Involvements
having furcation involvements exhibited cervical enamel projections, therefore one can only speculate as to the reason for the frequent location of furcation involve ments as exhibited in this study. Either the furcal surface closest to the cemento enamel junction is denuded first because it is in closest proximity to the inflamed gingiva, or a furca closely positioned to the cemento enamel junction is a structural area particularly prone to bone resorbtion from periodontal disease by virtue of its anatomical configuration or some other unknown factor.
TABLE 1. Number of Furcation Involvements Related to the Proximity of the Furca to the Cemento EnamelJ unction (According to Age Groups)
Age Groups of Skulls
Factors Related to Furcation
REFERENCES 1. G o l d m a n , H . M., and Cohen, D. W.: Periodontal Ther apy, 4th ed. St. Louis, T h e C. V. M o s b y Co., 1968. 2. G o l d m a n , H.: T h e r a p y of the incipient bifurcation in volvement. J Periodontol 2 9 : 112, 1958. 3. Schallhorn, R. G.: Eradication of bifurcation defects utilizing frozen autogenous hip m a r r o w implants. Periodont Abst 1 5 : 101, 1967. 4. N a b e r s , C. L., and O ' L e a r y , T. J.: Autogenous bone transplants in the t r e a t m e n t of osseous defects. J Periodontol 3 6 : 5, 1965. 5. Prichard, J.: Advanced Periodontal Disease; Surgical and Prosthetic Management. Philadelphia, W. B. Saunders Co., 1965. 6. L a r a t o , D. C : Furcation involvements: Incidence and distribution. In preparation. 7. Simring, M., and Goldberg, M.: The pulpal pocket approach: R e t r o g r a d e periodontitis. J Periodontol 3 5 : 22, 1964. 8. Masters, D. H., and Hoskins, S. W.: Projection of cervical enamel into molar furcations. J Periodontol 3 5 : 49, 1963. 9. Masters, D. H . Ibid.
Announcement BOSTON UNIVERSITY
SCHOOL OF GRADUATE
DENTISTRY
C O U R S E IN ITS C O N T I N U I N G
T H E M A N A G E M E N T OF CLINICAL PROBLEMS "What Do You Do When
November 22, 1975 Henry M. Goldman, D.M.D. Dean of the School Professor of Stomatology Herbert Schilder, D.D.S. Professor and Chairman Department of Endodontics Leo Talkov, D.M.D. Professor and Chairman Department of Prosthetics
ANNOUNCES
EDUCATION
THE
FOLLOWING
PROGRAM
This course is designed to identify and solve the exasperating " W h a t do you do when.. problems that arise often in the practice of general dentistry. Practical examples of clinical management problems are dis cussed in detail from initial diagnosis through final treatment proce dures. Also to be discussed are sudden unexpected problems like root perforation during post preparation procedures, loss of attached gingiva from abutment teeth, washout of abutments under permanently cemented full coverage cases, unexpected pulp exposure during full crown preparations, etc. The school is delighted to make Drs. Gold man, Schilder, and Talkov available for this very special day in clinical management. If registrants desire, they may submit documented management problems prior to November 7 for inclusion in the day's discussion. Fee: $80
Some Anatomical Factors Related to Furcation Involvements
7
by D.
C . LARATO, B.A., D . D . S . ,
M.S.D.*
THE TERM "furcation involvement" refers to the exten sion of pocket formation into the interradicular area of bone of multi-rooted teeth. In the past, teeth with furcation involvements were given a poor prognosis. New concepts of periodontal therapy have now provided dentists with the means to treat such teeth, enabling them to be retained with a good prognosis. Because the treatment of the furcal lesion requires an understanding of the actual disease process involved, it behooves the dentist to know as much as possible about the nature of furcation involvements. In an earlier study by this author, using dry human skull specimens, it was found that the average number of furcation involvements per skull increased with age, and that the first permanent molars most often exhibited denudation of the furca as a result of periodontal disease. The incidence of furcal disease was also found to be related to the length of time the tooth was present in the oral cavity. In addition, the more posterior the position of the tooth in the dental arch, the less the chance the tooth would develop a furcation involvement. It was also observed that in the maxilla and mandible, the buccal aspects of molar furcations were most often denuded as a result of periodontal disease. In the maxilla the second most commonly involved surface was the mesial surface of the furcation. Of all multi-rooted teeth, the maxillary first bicuspids had the lowest incidence of furcation involvements. As a result of these findings, a study was designed to determine whether the position of the root furcation in relation to the cemento enamel junction influences the location of furcation involvements. 1
2-6
8
6
RESULTS
Of a total of 188 furcation involvements, 142 (75%) of the involved furcations were located closer to the ce mento enamel junction than the noninvolved root sur faces (Table 1). In the maxilla 65%, and in the mandible 85% of the root surfaces exhibiting a furcation involve ment were located nearer to the cemento enamel junc tion of the tooth than the noninvolved root surface(s) (Table 2). Of the 188 teeth with furcation involvements only 24 (13%) exhibited cervical enamel projections. DISCUSSION
The high percentage of furcation involvements found associated with a close proximity of the furca to the cemento enamel junction, suggests that the furcal surface closest to the cemento enamel junction of the tooth is the area most susceptible to bone denudation as a result of periodontal disease. A question arises however, as to why the furcal area closest to the cemento enamel junction is most often involved, when bone destruction from perio dontal disease often exhibits an uneven pattern of bone loss. Masters examined a total of 474 extracted permanent maxillary and mandibular molar teeth for the presence of cervical enamel projections. N o attempt was made to select teeth extracted specifically because of periodontal disease. He felt, that when a projection of enamel extended into a root bifurcation, there could be no true fibrous attachment of the periodontal ligament, but rather an attachment of cervicular epithelium to the enamel projection. Such an arrangement he suggested, was highly susceptible to pocket formation in the pres-
MATERIAL AND METHODS
The experimental sample consisted of the same 305 dry human skull specimens of Mexican origin used in the prior study.f Information concerning the age and sex of the skulls was not available, therefore the age of each specimen could only be estimated by the degree of suture closure. The skulls were divided into four approximate age groups as shown in Table 1. Only skulls having 32
9
* Veterans Administration Hospital, Denver, Colorado. t Skulls obtained from the Atkinson Museum of Applied Anatomy School of Applied Anatomy School of Dentistry, University of the Pacific, San Francisco, Calif.
608
Volume 46 Number 10
Anatomical
Total N o . of Skulls Examined
No. of Furcation Involvements
No. of Furcation Involvements Related to the Closeness of the Furca to C E Junction
17-29 yrs.
40
2
2
30-44 yrs. 45-59 yrs. 60 yrs.
59 84 122
22 49 115
17 39 84
Total
305
188
142
(100%)
SUMMARY
A total of 305 dry human skull specimens were examined for the presence of furcation involvements. Of a total of 188 furcation involvements, 142 (75%) were related to the close proximity of the furcation to the cemento enamel junction of the tooth.
(75%)
TABLE 2. Number of Furcation Involvements Related to the Proximity of the Furca to the Cemento EnamelJ unction {Maxilla and Mandible) No. of Furcation No. of Furcation Involvements in 305 Skulls
Involvements Related to the Closeness of the Furca to C E Junction
Maxilla
99
65
Mandible
89
77
188
142
Junction
Total
ence of even slight gingival inflammation. He found that 24% of the 474 teeth he examined had cervical enamel projections, and preliminary clinical findings made by him indicated that enamel projections were found in more than 90% of the isolated periodontal involvements of mandibular root bifurcations. In this author's study only 24 (13%) of the 188 teeth
Involvements
having furcation involvements exhibited cervical enamel projections, therefore one can only speculate as to the reason for the frequent location of furcation involve ments as exhibited in this study. Either the furcal surface closest to the cemento enamel junction is denuded first because it is in closest proximity to the inflamed gingiva, or a furca closely positioned to the cemento enamel junction is a structural area particularly prone to bone resorbtion from periodontal disease by virtue of its anatomical configuration or some other unknown factor.
TABLE 1. Number of Furcation Involvements Related to the Proximity of the Furca to the Cemento EnamelJ unction (According to Age Groups)
Age Groups of Skulls
Factors Related to Furcation
REFERENCES 1. G o l d m a n , H . M., and Cohen, D. W.: Periodontal Ther apy, 4th ed. St. Louis, T h e C. V. M o s b y Co., 1968. 2. G o l d m a n , H.: T h e r a p y of the incipient bifurcation in volvement. J Periodontol 2 9 : 112, 1958. 3. Schallhorn, R. G.: Eradication of bifurcation defects utilizing frozen autogenous hip m a r r o w implants. Periodont Abst 1 5 : 101, 1967. 4. N a b e r s , C. L., and O ' L e a r y , T. J.: Autogenous bone transplants in the t r e a t m e n t of osseous defects. J Periodontol 3 6 : 5, 1965. 5. Prichard, J.: Advanced Periodontal Disease; Surgical and Prosthetic Management. Philadelphia, W. B. Saunders Co., 1965. 6. L a r a t o , D. C : Furcation involvements: Incidence and distribution. In preparation. 7. Simring, M., and Goldberg, M.: The pulpal pocket approach: R e t r o g r a d e periodontitis. J Periodontol 3 5 : 22, 1964. 8. Masters, D. H., and Hoskins, S. W.: Projection of cervical enamel into molar furcations. J Periodontol 3 5 : 49, 1963. 9. Masters, D. H . Ibid.
Announcement BOSTON UNIVERSITY
SCHOOL OF GRADUATE
DENTISTRY
C O U R S E IN ITS C O N T I N U I N G
T H E M A N A G E M E N T OF CLINICAL PROBLEMS "What Do You Do When
November 22, 1975 Henry M. Goldman, D.M.D. Dean of the School Professor of Stomatology Herbert Schilder, D.D.S. Professor and Chairman Department of Endodontics Leo Talkov, D.M.D. Professor and Chairman Department of Prosthetics
ANNOUNCES
EDUCATION
THE
FOLLOWING
PROGRAM
This course is designed to identify and solve the exasperating " W h a t do you do when.. problems that arise often in the practice of general dentistry. Practical examples of clinical management problems are dis cussed in detail from initial diagnosis through final treatment proce dures. Also to be discussed are sudden unexpected problems like root perforation during post preparation procedures, loss of attached gingiva from abutment teeth, washout of abutments under permanently cemented full coverage cases, unexpected pulp exposure during full crown preparations, etc. The school is delighted to make Drs. Gold man, Schilder, and Talkov available for this very special day in clinical management. If registrants desire, they may submit documented management problems prior to November 7 for inclusion in the day's discussion. Fee: $80
