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Advances in restorative dentistry
ADVANCES IN RESTORATIVE
DENTISTRY
NATHAN LEWIS DUBIN, D.M.D. Hartford,
Corm.
DEPENDS not only on basic concepts, theories, ultra high-speed techniques, electronics, ultrasonics, and restorative materials, but also on the understanding of the physiology of the mouth, its supporting structures, and the jaws. Emphasis must be placed on the stabilization of the remaining teeth and the development of an occlusion that is in harmony with functional jaw movements so that the periodontium and the supporting bone can be maintained in a healthy condition.’ A thorough examination of the patient and evaluation of all available data are the essential elements that are necessary for comprehensive diagnosis and treatment planning and they determine the success or failure of extensive restorative dentistry. The data should include : (1) a complete medical history, (2) a thorough clinical examination, (3 ) complete mouth roentgenograms, including 14 intraoral films, 2 bite-wing films (ultra fast), and extraoral panoramic films, (4) accurately occluded diagnostic and working casts, (5) preoperative color photographs, and (6) a study of emotional and psychogenic factors.
D
ENTETRY
FACTORS
OF HARMONIOUS
OCCLUSION
“The need to produce a harmonious occlusion always must be kept in mind when restoring teeth with crowns, bridges, inlays or onlays. Otherwise, complete mouth reconstruction may result in complete mouth destruction.“2 “The gains of occluso-rehabilitation in the saving of teeth are inextricably linked to a greater knowledge today of dental occlusion, articulation and muscle physiology.“” Although we can improve on nature, we must never overstep our bounds. Failure can result from overzealous and numerous unwarranted changes. Many mouths are better left untouched. Each problem must be weighed with all available scientific and practical knowledge. Form and function go hand in hand. An arithmetical normal occlusion cannot be created by increasing or decreasing the vertical relation of occlusion beyond the limits of interocclusal clearance. The goal in occlusal rehabilitation is that of rebuilding a disordered dental mechanism into an orderly one with maximum tooth contact during function. The finished restorations must result in the distribution of stress over the largest number of teeth and reduce the strain on each individual tooth to a minimum. Thereby, a state of physiologic tone and health is created for all teeth and their inresting tissues (Fig. 1 j.
J. r’uos. Ih. Scpt:(h, 1964
Fig. 1.-A,
The pretreatment
periodontal and prosthetic tional restoration.
problem.
B, The post-treatment
func-
Fig. 2.-A mouth that has advanced periodontal involvement is treated by a combined therapy that includes periodontics, surgery, orthodontics, and prosthodontics. A, The diagnostic pretreatment casts. B, A section of the periodontal pack is in position following a gingivectomy.
\‘dume Numhrr
14 5
IMPORTANCE
ADVANCES
OF FULL
COVERAGE
In’
RESTORATIVE
TO OCCLUSAL
051
DEKTISTRY
REHABILITATION
Much controversy exists concerning the deleterious effects of full coverage crowns. Although some restorations that cover less tooth structure than full crowns are fine precision castings, they are unacceptable for occlusal rehabilitation because they may be (1) unsightly in appearance, (2) cumbersome in shape, (3) anatomically incorrect, (4) not caries resistant, (5) irritating to gingivae, and often (6) cannot be made retentive or parallel to one another so that occlusal forces can be distributed along the long axes of the teeth. Full coverage crowns are largely the restorations of choice for occlusal rehabilitation. However, definite requirements are essential for good results. These include (1) the meticulous preparation of each tooth, (2) an anatomically correct form and contour of the restorations, (3) a perfect marginal fit to protect the periodontal tissues, (4) proper fabrication, and (5) esthetics acceptable to both the dentist and the patient. VACUUM-FIRED
PORCELAIN
Vacuum-fired porcelain fused to gold is the finest material for full coverage crowns and fixed partial dentures in mouths with a high caries index, advanced periodontal disease, malformation of clinical crowns, and faulty occlusion (Fig. 2). The advantages of porcelain fused to gold over other materials are in its (1) accuracy of fit, (2) strength with little attritional and abrasive wear, (3) lifelike appearance, (4) compatibility with soft tissue, (5) hygiene, (6) color stability, (7) reduced pressure on the teeth and underlying bone, (8) insurance against recurrent decay, (9) ease in shaping for anatomic and functional occlusion, and (10) ease of repair. “Porcelain is one of the oldest restorative materials used in dentistry. In many ways, its physical properties are comparable to those of enamel. It can be molded, contoured, and fired to any form desired, and its smooth, hard surface makes it compatible with soft tissues. The similarity of the available translucent porcelain to tooth structure makes porcelain restorations inconspicuous.“4 Glazed porcelain
Fig.
3.-A,
Before
treatment.
B, The
teeth have been restorations.
restored
with
porcelain
fused
to
gold
Fig.
4.-Porcelain
i
\
fused
to gold restorations may resemble porcel,ain anterior crown. B, A posterior crown.
jacket
crowns.
A, An
\
L\\, \ Fig. 5.-A
porcelain
veneer
may be fused to gold restorations. posterior crown.
A,
An anterior
crown.
B, A
is the most benign material to the tissue that can be placed in the oral cavity and is the most natural and vital appearing dental material available. Glazed porcelain is impervious to mouth fluids and is nonporous and color fast. However, porcelain used by itself has many limitations. It has a tendency to fracture under stress and has little edge strength. Therefore, it was necessary to design a functional restoration with hidden strength by fusing porcelain to an individually constructed, strong understructure of precision cast gold. The two materials are well wed, and the results with vacuum firing are unsurpassed (Fig. 3). There are two types of porcelain fused to gold restorations. All visible gold is covered with porcelain for the one type so that the finished restoration resembles a porcelain jacket crown (Fig. 4). The other type is the veneer crown with porce-
volunlc Nunhe
I-I 5
i\DVANCES
Fig. G.--Processing
equipment
1X
RESTORATIVE
DENTISTRY
of this type is used in construction fused to gold restorations.
053
of vacuum-fired
porcelain
lain fused onto the labial or buccal surfaces (Fig. 5 1. The porcelain veneer crown requires no loops, undercuts, or other mechanical forms of retention in the gold casting. The bond of the porcelain fused to gold is so strong that all such aids are superfluous. The combination of gold and porcelain gives all of the advantages of both materials, while their individual disadvantages are eliminated. The strength and fit of gold are combined with the beauty and function of glazed porcelain. \7acuuni firing prevents air-cell formation and produces a dense porcelain. Such restorations are vital in appearance, thin, non-bulky, and have fine shades (Fig. 6). Acrylic resins are undesirable in many situations hecause they are subject to wear and discoloration. They may l,ecmne irritating to the gingival tissues, can absorb mouth fluids and odors, and are extremely difficult to repair properly. However, acrylic resin veneers must be used with full cast crowns or other types of restorations where there is not a space of at least 2 mm. between the occlusal surfaces of the prepared teeth and the teeth of the opposing dental arch. CONCLUSIONS
The aims of preventive oral rehabilitation are to preserve and protect the dentition in its Rest state of health with properly constructed restorations that stabilize the remaining teeth against destructive forces. Pathologic dentitions can he restored to healthy masticatory units of the whole biologic apparatus by conservative, coniprehensive diagnosis and treatment planning, scientific and esthetically designed restorations, and the establishment of a harmonious occlusion.
1. l)uhin,
IC. I>.: Advances 1956.
in Functional
Occlusal
Rehabilitation.
J. PROS. Der.
6:252-258.
954
J. Pros. Den. SepbOct., 1964
DUBIPi
2. SwensoTb61$ M. : Complete Mouth Reconstruction or Destruction?
J.A.D.A.
65 :345-350,
3. Cohn, L. A:: Occluso-Rehabilitation: Principles of Diagnosis and Treatment Planning, D. Clin. North America, p. 259-281, 1962. 4. Bartels, J. C.: Dental Ceramics, J. PROS. DEN. 11437..551, 1961. 18 ASYLUM ST. HARTFORD 3. CONN.
DENTISTRY
NATHAN LEWIS DUBIN, D.M.D. Hartford,
Corm.
DEPENDS not only on basic concepts, theories, ultra high-speed techniques, electronics, ultrasonics, and restorative materials, but also on the understanding of the physiology of the mouth, its supporting structures, and the jaws. Emphasis must be placed on the stabilization of the remaining teeth and the development of an occlusion that is in harmony with functional jaw movements so that the periodontium and the supporting bone can be maintained in a healthy condition.’ A thorough examination of the patient and evaluation of all available data are the essential elements that are necessary for comprehensive diagnosis and treatment planning and they determine the success or failure of extensive restorative dentistry. The data should include : (1) a complete medical history, (2) a thorough clinical examination, (3 ) complete mouth roentgenograms, including 14 intraoral films, 2 bite-wing films (ultra fast), and extraoral panoramic films, (4) accurately occluded diagnostic and working casts, (5) preoperative color photographs, and (6) a study of emotional and psychogenic factors.
D
ENTETRY
FACTORS
OF HARMONIOUS
OCCLUSION
“The need to produce a harmonious occlusion always must be kept in mind when restoring teeth with crowns, bridges, inlays or onlays. Otherwise, complete mouth reconstruction may result in complete mouth destruction.“2 “The gains of occluso-rehabilitation in the saving of teeth are inextricably linked to a greater knowledge today of dental occlusion, articulation and muscle physiology.“” Although we can improve on nature, we must never overstep our bounds. Failure can result from overzealous and numerous unwarranted changes. Many mouths are better left untouched. Each problem must be weighed with all available scientific and practical knowledge. Form and function go hand in hand. An arithmetical normal occlusion cannot be created by increasing or decreasing the vertical relation of occlusion beyond the limits of interocclusal clearance. The goal in occlusal rehabilitation is that of rebuilding a disordered dental mechanism into an orderly one with maximum tooth contact during function. The finished restorations must result in the distribution of stress over the largest number of teeth and reduce the strain on each individual tooth to a minimum. Thereby, a state of physiologic tone and health is created for all teeth and their inresting tissues (Fig. 1 j.
J. r’uos. Ih. Scpt:(h, 1964
Fig. 1.-A,
The pretreatment
periodontal and prosthetic tional restoration.
problem.
B, The post-treatment
func-
Fig. 2.-A mouth that has advanced periodontal involvement is treated by a combined therapy that includes periodontics, surgery, orthodontics, and prosthodontics. A, The diagnostic pretreatment casts. B, A section of the periodontal pack is in position following a gingivectomy.
\‘dume Numhrr
14 5
IMPORTANCE
ADVANCES
OF FULL
COVERAGE
In’
RESTORATIVE
TO OCCLUSAL
051
DEKTISTRY
REHABILITATION
Much controversy exists concerning the deleterious effects of full coverage crowns. Although some restorations that cover less tooth structure than full crowns are fine precision castings, they are unacceptable for occlusal rehabilitation because they may be (1) unsightly in appearance, (2) cumbersome in shape, (3) anatomically incorrect, (4) not caries resistant, (5) irritating to gingivae, and often (6) cannot be made retentive or parallel to one another so that occlusal forces can be distributed along the long axes of the teeth. Full coverage crowns are largely the restorations of choice for occlusal rehabilitation. However, definite requirements are essential for good results. These include (1) the meticulous preparation of each tooth, (2) an anatomically correct form and contour of the restorations, (3) a perfect marginal fit to protect the periodontal tissues, (4) proper fabrication, and (5) esthetics acceptable to both the dentist and the patient. VACUUM-FIRED
PORCELAIN
Vacuum-fired porcelain fused to gold is the finest material for full coverage crowns and fixed partial dentures in mouths with a high caries index, advanced periodontal disease, malformation of clinical crowns, and faulty occlusion (Fig. 2). The advantages of porcelain fused to gold over other materials are in its (1) accuracy of fit, (2) strength with little attritional and abrasive wear, (3) lifelike appearance, (4) compatibility with soft tissue, (5) hygiene, (6) color stability, (7) reduced pressure on the teeth and underlying bone, (8) insurance against recurrent decay, (9) ease in shaping for anatomic and functional occlusion, and (10) ease of repair. “Porcelain is one of the oldest restorative materials used in dentistry. In many ways, its physical properties are comparable to those of enamel. It can be molded, contoured, and fired to any form desired, and its smooth, hard surface makes it compatible with soft tissues. The similarity of the available translucent porcelain to tooth structure makes porcelain restorations inconspicuous.“4 Glazed porcelain
Fig.
3.-A,
Before
treatment.
B, The
teeth have been restorations.
restored
with
porcelain
fused
to
gold
Fig.
4.-Porcelain
i
\
fused
to gold restorations may resemble porcel,ain anterior crown. B, A posterior crown.
jacket
crowns.
A, An
\
L\\, \ Fig. 5.-A
porcelain
veneer
may be fused to gold restorations. posterior crown.
A,
An anterior
crown.
B, A
is the most benign material to the tissue that can be placed in the oral cavity and is the most natural and vital appearing dental material available. Glazed porcelain is impervious to mouth fluids and is nonporous and color fast. However, porcelain used by itself has many limitations. It has a tendency to fracture under stress and has little edge strength. Therefore, it was necessary to design a functional restoration with hidden strength by fusing porcelain to an individually constructed, strong understructure of precision cast gold. The two materials are well wed, and the results with vacuum firing are unsurpassed (Fig. 3). There are two types of porcelain fused to gold restorations. All visible gold is covered with porcelain for the one type so that the finished restoration resembles a porcelain jacket crown (Fig. 4). The other type is the veneer crown with porce-
volunlc Nunhe
I-I 5
i\DVANCES
Fig. G.--Processing
equipment
1X
RESTORATIVE
DENTISTRY
of this type is used in construction fused to gold restorations.
053
of vacuum-fired
porcelain
lain fused onto the labial or buccal surfaces (Fig. 5 1. The porcelain veneer crown requires no loops, undercuts, or other mechanical forms of retention in the gold casting. The bond of the porcelain fused to gold is so strong that all such aids are superfluous. The combination of gold and porcelain gives all of the advantages of both materials, while their individual disadvantages are eliminated. The strength and fit of gold are combined with the beauty and function of glazed porcelain. \7acuuni firing prevents air-cell formation and produces a dense porcelain. Such restorations are vital in appearance, thin, non-bulky, and have fine shades (Fig. 6). Acrylic resins are undesirable in many situations hecause they are subject to wear and discoloration. They may l,ecmne irritating to the gingival tissues, can absorb mouth fluids and odors, and are extremely difficult to repair properly. However, acrylic resin veneers must be used with full cast crowns or other types of restorations where there is not a space of at least 2 mm. between the occlusal surfaces of the prepared teeth and the teeth of the opposing dental arch. CONCLUSIONS
The aims of preventive oral rehabilitation are to preserve and protect the dentition in its Rest state of health with properly constructed restorations that stabilize the remaining teeth against destructive forces. Pathologic dentitions can he restored to healthy masticatory units of the whole biologic apparatus by conservative, coniprehensive diagnosis and treatment planning, scientific and esthetically designed restorations, and the establishment of a harmonious occlusion.
1. l)uhin,
IC. I>.: Advances 1956.
in Functional
Occlusal
Rehabilitation.
J. PROS. Der.
6:252-258.
954
J. Pros. Den. SepbOct., 1964
DUBIPi
2. SwensoTb61$ M. : Complete Mouth Reconstruction or Destruction?
J.A.D.A.
65 :345-350,
3. Cohn, L. A:: Occluso-Rehabilitation: Principles of Diagnosis and Treatment Planning, D. Clin. North America, p. 259-281, 1962. 4. Bartels, J. C.: Dental Ceramics, J. PROS. DEN. 11437..551, 1961. 18 ASYLUM ST. HARTFORD 3. CONN.