29 Microsurgery A therapeutic revolution has taken place in gen- cation, has become an integral part of modern Three types of keplerian loupes are common- eral surgery requiring the retraining of thousands dental practices. ly employed in dentistry: simple single-element of surgeons and the retooling of their operating loupes (Figures 29-3 and 29-4), compound loupes rooms. This change has come about owing to the (Figures 29-5 and 29-6), and prism telescopic Magnification Systems acceptance of microscopic surgery in many areas loupes (Figures 29-7 and 29-8). Each type may dif- of medicine, such as vascular, corneal, otologic, A variety of simple and complex magnification fer widely in optical sophistication and individual neurologic, gynecologic, and, in particular, laparo- systems are available to practitioners, ranging construction (Table 29-1). For most periodontal scopic and arthroscopic procedures. from simple loupes to prism telescopic loupes procedures performed using loupe magnification These procedures were a natural evolution of and, ultimately, to the surgical microscope. Each for increased preciseness, either compound or microsurgical advances and have become accept- magnification system has specific advantages and prism loupes, of ×4 to ×5 magnification, are used ed as routine by the general public. Over the past limitations. When selecting which mode of mag- to provide the most effective combination of mag- decade, the field of periodontics has seen increas- nification should be used for improved visual nification, field size, and depth of focus. ing surgical refinement of many procedures. Such acuity, the task at hand must be considered. The refinements require more detailed surgical skills assumption that more magnification is better Simple Loupes resulting from increased visual acuity. Consistent must be weighed against the decrease in field of Simple loupes consist of a pair of single, positive, successful guided tissue regeneration, cosmetic view and depth of focus that occurs as magnifica- side-by-side menicus lenses (see Figure 29-4). crown lengthening, gingival augmentation pro- tion increases (Figure 29-1). Therefore, an under- Such loupes are primitive magnifiers, with limit- cedures, soft and hard tissue ridge augmentation, standing of the optical principles that govern ed capabilities. Each lens has two refracting sur- osseous resection, and dental implants demand magnification is essential to the successful use of faces, with one occurring as light enters the lens clinical expertise that challenges the technical magnification in the clinical practice of dentistry. and the other when it leaves. The magnification skills of periodontists to the limits of and beyond Microdentistry and periodontal microsurgery are of simple loupes can be increased only by aug- the range of normal visual acuity. acquired skills, requiring magnification, micro- menting the lens diameter or thickness. Because Periodontal microsurgery has thus evolved. surgical instruments, intensive training, and fre- of their size and weight limitations, they have no Periodontal microsurgery is not a specific opera- quent practice to achieve and maintain excellence. practical dental application beyond a magnifica- tion intended to replace traditional periodontal tion range of 1.5 diameters, where working dis- surgery but a methodology that improves all Magnifying Loupes tances and depths of field are compromised. aspects of surgical techniques. “Microsurgery” is Surgical loupes are the most common system of defined as refinements in existing basic surgical optical magnification used in dentistry. Funda- Compound Loupes techniques that are made possible by the use of the mentally, loupes are two monocular microscopes Compound loupes (see Figure 29-6) are converg- surgical microscope with subsequent, significant with side-by-side lenses converging to focus on ing multiple lenses with intervening air spaces to improved visual acuity. Traditional “macroscopic the operative field. The magnified image is gain additional refracting power, magnification, surgery” or “macrosurgery” is defined as those sur- formed with stereoscopic properties by virtue of working distance, and depth of field. They are gical procedures performed with the unaided eye, the convergent lenses. A convergent lens system is also “achromatic” (color correct), which is highly without the assistance of magnification. called a keplerian optical system (Figure 29-2). desirable. Size and weight are not significant Owing to the “visual advantage” gained with microsurgery, macrosurgery and microsurgery are not comparable. In macrosurgery, hand move- Eye ments are guided proprioceptively, whereas in microsurgery, they are guided visually. These visu- Lenses of eye piece ally guided movements not only position the hands for the execution of prelearned movements but also through their entire range of motion, with visual feedback and midcourse corrections. Visual- Binocular ly guided movements result in greater accuracy of objectives hand movements, which are retrained with use and practice. Microscopically visually guided move- ments allow the periodontist to achieve clinical results once thought unlikely on a consistent basis. Optical magnification has, therefore, broad- Object ened the horizons of dentistry in general and periodontics in particular. Improvement in visu- FIGURE 29-1 Magnifications (clockwise from upper FIGURE 29-2 Keplerian optics. al acuity, made possible through optical magnifi- left) 2×, 4×, 8×, and 16×. 434 Advanced Surgical Procedures FIGURE 29-3 Simple loupes. FIGURE 29-4 Simple loupe optical diagram. FIGURE 29-5 Compound loupes. FIGURE 29-6 Compound loupe optical diagram. FIGURE 29-7 Eyeglass-mounted prism loupes. FIGURE 29-8 Prism loupe optical diagram. problems for the ×4 to ×5 magnification com- Operating Microscope should also incorporate fully coated optics and monly used in periodontics. The surgical operating microscope is much more achromatic lenses, with high resolution and good versatile and advantageous than magnifying contrast stereoscopic vision. Prism Loupes loupes (Table 29-2). The microscope offers mul- Prism loupes are the most optically advanced tiple flexibility in magnification optics and com- Maneuverability type of loupe magnification presently available fort (Figure 29-9). Operating microscopes suit- (see Figure 29-8). Prism loupes contain Schmidt able for use in periodontics use galilean optical For practical use in periodontics, a surgical micro- or rooftop prisms, which lengthen the light path principles (Figure 29-10). scope must have maneuverability, stability, and an through a series of mirror reflections within the Such scopes use the application of the mag- adequate working distance for instrumentation. loupes, virtually folding the light so that the bar- nifying loupe in combination with a magnifica- Microscope mountings play an important role in rel of the loupe can be shortened. Only the surgi- tion changer and a binocular viewing system so maneuverability and scope stability and are avail- cal microscope can provide better magnification that the scopes employ parallel binoculars for able for the ceiling, the wall, or a floor stand. and optical characteristics than prism loupes. protection against eye strain and fatigue. They Maneuverability must always be sufficient to meet the requirements of clinicians for increased visual accessibility to the various anatomic struc- Table 29-1 Keplerian Loupes tures dealt with in periodontics. Inclinable eye- pieces are an indispensable necessity for the Maximum Usable Type Lens Magnification Advantages Disadvantages* maneuverability and flexibility necessary for the clinical use of the surgical microscope in peri- Simple Single 1.5 × Simplicity Spherical (shape) and odontics. Because the optical characteristics of chromatic (color) distortions most manufacturers’ lenses are comparable, with increased size and microscope maneuverability is often more weight increased important than optical characteristics in deter- magnifications mining the appropriate microscope for peri- Compound Multiple 3.0 × Increased magnification Limited depth of field odontal procedures (Figures 29-11 and 29-12). Limited field access Prism Multiple 4.0 × Higher magnification Increased weight above 4× Wide depth of field Illumination Longer working distances Larger fields of view Illumination of the field is an important consid- eration. Periodontists are accustomed to lateral *A major disadvantage of the design of keplerian loupes is that the clinician’s eyes must converge to view the operative field. This can result in eye strain, fatigue, and even vision changes, especially after prolonged use of poorly fitted loupes. illumination from side-mounted dental lights. Clinicians who work with loupes often require a Microsurgery 435 Table 29-2 Operating Microscope Maximum Usable Type Lens Magnification Advantages Disadvantages Microscopic Multiple 4–20× Binocular eyepieces Fixed positioning of patient Parallel optical eyepieces permit High initial setup costs relaxed stereoscopic viewing Limited site use to 60–80% Achromatic (color stable) lenses High resolution Efficient illumination Increased depth of field Increased field of view FIGURE 29-12 Periodontal operatory equipped for Ability to easily change microsurgery. magnification procedures of all types: either 35 mm slides or dig- ital photographs can be easily produced using a headlamp to compensate for the decreased Documentation beam splitter camera attachment (Figure 29-13). amount of light passing through the loupes. Documentation of periodontal procedures has With a foot-operated shutter control, the surgeon Until recently, coaxial fiber optic illumination become increasingly important for both dental- can compose the photographic field as the proce- had been a major advantage of the operating legal reasons and for patient and professional edu- dure unfolds without interrupting the surgical microscope over surgical loupes. Coaxial lighting cation purposes. The surgical operating micro- process for photography. An advantage of micro- places the light source parallel to the optical axis scope is ideal for documenting periodontal scopic photography is that it represents the surgi- via a prism beam splitter. With coaxial lighting, cal field exactly as the surgeon sees it as opposed to no shadows are produced, and the clinician can a photographer’s view produced from a different better view into the farthest reaches of the oral angle while the surgeon works. Excellent video cavity, including into some subgingival pockets Eye documentation is also available through the oper- and angular defects. Improved visualization of ating microscope using a video beam splitter root surface irregularities and deposits is pos- Lenses of eye piece attachment. High-resolution digital cameras with sible. The clinician is often able to view aspects of video and slide printers are currently replacing both normal and abnormal periodontal anatomy 35 mm camera photography in many microsurgi- never previously accessible. Clinical decisions cal disciplines. High-resolution S-VHS recorders can be made based on improved visual knowl- Prism assembly bring new capabilities for video recording of peri- edge of altered anatomy rather than educated odontal procedures for educational purposes. guesses. Coaxial lighting has also become avail- Binocular able in prism telescopic loupes. objectives Periodontal Microsurgery In recent years, periodontics has witnessed increasing refinement and consistency of proce- dures, requiring progressively more intricate sur- Object gical skills. Regenerative and resective osseous FIGURE 29-10 Galilean optics microscope diagram. surgery, periodontal plastic surgery, and dental implants demand clinical performance that chal- lenges the technical skills of periodontists beyond the range of ordinary visual acuity. FIGURE 29-9 Operating microscope. FIGURE 29-11 Microscope on a rotating mount. FIGURE 29-13 Microscope camera and beam splitter. 436 Advanced Surgical Procedures Periodontal microsurgery introduces the Conclusions possibility for considerably less invasive surgical procedures in periodontics, exemplified by small- Viewing periodontal surgery under magnification er, more precise surgical incisions for access and, cannot help but impress the clinician with the consequently, less need for vertical releasing inci- coarseness of conventional surgical manipulation. sions. Periodontists, like other microsurgeons, What appears to the unaided eye as gentle han- have been surprised by the extent to which dling is revealed, under magnification, as gross reduced incision size is directly related to reduced crushing and tearing of delicate tissues. Periodon- postoperative patient pain. FIGURE 29-14 Microsurgical instruments. Advantages 1. Less tissue trauma 2. Less mobility 3. Less patient anxiety 4. Atraumatic tissue management 5. Accurate primary wound closure 6. Increased diagnostic skills 7. Minimally invasive 8. Improved cosmetic results 9. Increased surgical quality A 10. Increased effectiveness of root débridement FIGURE 29-15 Castroviejo microsurgical scalpel. results in greater predictability of a. Regeneration procedures b. Cosmetic procedures Improved documentation a. Video b. Slide c. Digital Disadvantages 1. Educational requirements a. Surgical technique B b. Understanding of optics 2. Long adjustment period for clinical profi- ciency 3. Initial increased surgical time 4. Higher patient cost 5. Limited surgical access Microsurgical Instruments In addition to the use of magnification and reliance on atraumatic technique, microsurgery entails the use of specially constructed microsur- C gical instruments specifically designed to mini- FIGURE 29-16 Microsutures and microinstruments mize trauma (Figures 29-14 and 29-15). An at ×10 magnification. important characteristic of microsurgical instru- ments is their ability to create clean incisions to prepare the wound for healing by primary inten- tion. Such incisions are established at 90° angles to the surface using a Castroviejo microsurgical scalpel (Figure 29-16). Magnification permits easy identification of ragged wound edges for trim- ming and freshening. To permit primary wound closure, microsutures in the range of 6-0 to 9-0 (Figure 29-17) with microsurgical needle holders D are required to correctly approximate the wound FIGURE 29-18 A, Suture practice on latex at ×8 mag- edges (Figure 29-18). Microsurgical wound appo- nification. B, Suture practice on latex at ×24 magnifi- sition minimizes gaps or voids at the wound cation. C, Suture practice on latex at ×32 magnifica- edges, which encourages rapid healing, with less tion. D, Suture practice on foliage (anthurium flower) postoperative inflammation and less pain. FIGURE 29-17 Sutures in human hair. at ×32 magnification. Microsurgery 437 tists have attempted to treat the surgical site atrau- Periodontal surgery is a natural extension of matically to achieve primary wound closure. conventional surgical principles by which magni- However, the limits of normal vision dictate the fication is employed to permit accurate and extent to which this goal is possible. For surgeons atraumatic handling of soft and hard tissues to who perform periodontal surgery to continue to enhance wound healing. live up to their reputation of being experts in deft- Figures 29-19 to 29-21 illustrate periodon- ly handling soft and hard tissues, proficiency in tal surgery cases treated using microsurgical periodontal microsurgery is a necessity. techniques. A1 B1 A2 B2 A3 B3 FIGURE 29-19 A, 1, Deep-wide gingival recession on maxillary cuspid. 2, Microsurgical subepithelial con- nective tissue graft ×4 magnification. 3, Same case viewed at ×20 magnification. 4, Final postoperative result. B, 1, Multiple areas of recession (central incisor and cuspid). 2, Microsurgical subepithelial connective tissue graft sutured with minimal trauma. 3, One-month postoperative result. A4 438 Advanced Surgical Procedures A1 A2 A3 B1 B2 B3 FIGURE 29-20 A, 1, Mucogingival frenum abnormality with slight recession. 2, Subepithelial microsurgery to reposition the frenum and augment attached gingiva with a connective tissue graft. 3, One-month postoperative result. B, 1, Multiple areas of gingival recession. 2, Mirosurgical subepithelial connective tissue graft with a coro- nally positioned flap. 3, Final result with 100% root coverage. A1 A2 A3 B1 B2 B3 FIGURE 29-21 A, 1, Papilla reconstruction prior to surgery. 2, Microsurgical view of papillary reconstruction. 3, Papillary reconstruction completed. B, 1, Significant recession on the canine tooth. 2, Microsurgical subepithelial connective tissue graft coverage by a double-papilla flap. 3, Complete root coverage with a wide zone of keratinized gingiva, 3-month result.
Pages to are hidden for
"ch29 (PDF)"Please download to view full document