WHAT DR KENNETH LEW'S RESEARCH MEANS TO YOU.
Q. What is the strength that underpins Dr Kenneth Lew’s clinical practice?
Q. What are themes that threads through Dr Kenneth Lew’s almost 10 years of clinical dental research?
A. It is a strong commitment to a Face and Profile Centric Orthodontic Diagnosis, the linchpin being Dr Kenneth Lew’s internationally refereed research on The Ideal Asian facial profiles and how Orthodontics can help achieve an esthetic and stable result for his patients.
READ BELOW… A SNAPSHOT OF how Dr Kenneth Lew’s scholarly academic research may be relevant to you, as his Patient, or you, as his mentored Dentist!
Dr Kenneth Lew BDS (Singapore), MDS Orthodontics (Adelaide), FDSRCS (Edinburgh), FAMS (Singapore)
Founder, Clinical Mentor Director and board certified Specialist Orthodontist, TANGLIN DENTAL SURGEONS INVISIBLE BRACES CENTER
Dr Kenneth Lew received his Dental Degree from the National University of Singapore in 1985, his Masters with Specialty Training in Orthodontics from the University of Adelaide in 1987, his Fellowship in Dental Surgery from the Royal College of Surgeons in Edinburgh without examination (as a recognition of his contribution to Orthodontics) in 1992 and his Fellowship from the Academy of Medicine in Singapore in Orthodontics in 1992.
Dr Kenneth Lew graduated from dental school as the Best Clinical Student and the prestigious Cheah Cheng Kooi University medal for his final BDS examination whilst on a coveted undergraduate Public Service Commission Scholarship. He went on to his postgraduate specialist orthodontic masters degree on a National University of Singapore Postgraduate Scholarship.
Passionate about giving his patients in Tanglin Dental Surgeons a Face and Profile-centric orthodontic diagnosis and treatment, Dr Kenneth Lew’s earlier career lecturing Orthodontics in NUS presented him with the opportunity of delving into scholarly research on orthodontics.
Dr Kenneth Lew’s Basic Science-Centric Orthodontic Scholarly Research
His research got off the ground with a SEM and Transmission Electron Microscope (TEM) study of the microvasculature changes incident to orthodontic tooth extrusion (1); a morphological and morphometric study of the periodontal ligament (2); and tooth extrusion effects on microvessel volumes, endothelial areas and fenestrae in molar apical periodontal ligament (3)( which was later quoted or cited by 22 researchers in their own studies). Dr Kenneth Lew’s research was conducted under the auspices of the University of Adelaide, supervised by his mentor, the well-regarded doyen of research, late Professor (Dr) Milton Sims. Kenneth Lew spent hours in the laboratory (risking angry nips by rats), anesthesizing and cannulating via the aorta, six 12 week old male Porton rats, after applying an 1N extrusive force on the rats’ right maxillary first molars (4).
Lew’ research added to his clinical understanding how teeth and supporting periodontal ligament reacts to different types of loading and force in patients undergoing dental braces (orthodontic) treatment. Indeed, if there were no periodontal ligament, there would be no orthodontic tooth movement because teeth would be otherwise fused to the jaw bone (5).
Dr Kenneth Lew’s Esthetic Face-Driven Orthodontic Research
Lew’s return to Singapore in 1987 marked a shift to more clinically-driven research. His keen interest in dento-facial esthetics, piqued his interest in the role and extent orthodontics ( the exercise generally perceived of ‘straightening crooked teeth’) could change his patients’ smile-lines, facial profiles and frontal facial appearances. Dr Kenneth Lew realized that most of his patients who looked to him to ‘straighten’ their teeth, are esthetically motivated, and motivated to improve their appearance beyond just aligning their crooked teeth.
Lew also noted that nice, straight teeth does not on its own mean good facial balance. Dr Kenneth Lew’s realizes that a good clinician must understand soft tissue behavior in relation to orthodontic and orthopaedic changes, and also must comprehend growth and development of various soft tissue traits. Soft tissue is the major factor determining his patients’ final facial profile (6). At that point time, most academic research revolved around the ideals and norms of the largely Caucasian population sample.
But to realize all this was not good enough, Dr Kenneth Lew knew that clinicians had to work with numbers, angles, norms, deviations from the norms. Only then could he treat his patients to an ideal facial profile.
Dr Kenneth Lew then carried out a double blind selection process comprising pofessional and lay judges who analysed the cephalometric tracings of a sample of 48 Chinese adults with ‘aesthetically pleasing profiles’. Dr Lew then established that in comparison with white norms, the Chinese nose was less prominent (P<.01), the nasolabial angle was less obtuse (P<.01), both upper and lower lips were more protrusive (P<.05), the upper lip curvature was greater (P<.01), and the soft tissue chin thickness was less (P<.0.5) (7).
This variance between racial types emphasizes the need to recognize that soft tissue lateral cephalometric norms are specific for the racial group and cannot be applied across the different racial types. Dr Kenneth Lew’s pioneering research on Chinese facial profiles is published in the respected Journal of Oral and Maxillofacial Surgery, indeed helpful - it seeks to give guidance to clinicians when treating their Chinese patients.
These findings on Chinese facial profiles by a Dr Kenneth Lew, a Singaporean orthodontist, has been cited by 45 international research papers. Later researchers citing his study on Chinese profiles, subsequently report that ethnicity of the judges is a significant factor in influencing the perception of an esthetic lip position. The Chinese judges prefer a more retrusive (or straighter profile) and are more likely to rate a protrusive facial profile as unacceptable, compared to White judges (8).
South Indian facial profiles
Dr Kenneth Lew’s research is used to establish the soft tissue cepahlometric norms for the Mahabubnagar population in South India. Indeed, males have thicker soft tissue structures, acute nasolabial angles, increased facial lengths and heights, increased midface deficiency, recessive lower face, more convex profiles and less upright mandibular incisors than females in this South Indian population (9).
Dr Kenneth Lew’s Academic Research on Cephalometric Ideals in Chinese, Malay and Indian Population
Driven by a strong desire to do the best by his patient base, Dr Kenneth Lew went on to establish that in a sample of 105 females (35 Chinese, 35 Malay, 35 Indian) all with good occlusion and aesthetically pleasing facial profiles (as determined by a trained clinician and endorsed by the lay public), the cephalometric ideals of the Chinese and Malay ethnic groups are rather similar, but cepahlometric differences exist between the Chinese and Indian, and as well as between the Malays and Indians.
Compared to the Chinese and Malays, Dr Kenneth Lew has established that Indians appear to have less prognathic mandibles and maxillae, less protrusive and proclined upper and lower incisors and also less protrusive upper and lower lips (10)
Dr Kenneth Lew’s research is published in the peer reviewed Asian Journal of Aesthetic Dentistry and thus shows that there are intrinsic ethnic differences and an orthodontist or clinician would be well placed to be sensitive to this aspect; and when he treats patients of different ethnic groups, it is clinically appropriate and proper for the orthodontist to consider and use cephalometric ideals (not norms or averages) which are peculiar to their own ethnic group (10). Dr Kenneth Lew’s research piece continues to be referred to and is cited by 19 other international research papers.
Indeed, researchers citing Dr Kenneth Lew’s academic paper (10) have found that the Malaysian Malay maxilla and mandible are set more forward that Caucasian, and the Malaysian Malay show more bimaxillary protrusion than the Caucasian, has more protrusive upper and lower lips, and less prominent chin than the Caucasian (11).
All this research adds to Dr Kenneth Lew’s depth of understanding of how to treat his orthodontic braces patients to an Ideal Facial Profile, and what the Ideal is for different patients who seek him for dental braces treatment in Tanglin Dental Surgeons Invisible Braces Center.
Dr Kenneth Lew’s Research on Soft to Hard Tissue Lip Response and Facial Profile Preference
In his boutique style Tanglin Dental Surgeons Invisible Braces Center, Dr Kenneth Lew has found his métier treating patients and correcting their smiles with orthodontics and in more severe cases, orthognathic surgery. His is a strongly esthetically driven orthodontic practice where aesthetic form and biological function sit side by side.
Lew’s particular area of interest lies in soft tissue profile changes following orthodontic treatment of Chinese adults with Class III malocclusions (12) as seen in his research chosen to be included in The International Journal of Adult Orthodontics and Orthognathic Surgery.
Here, Dr Kenneth Lew examines a sample of 38 adult Chinese patients ( mean age 24.3 +- 3.2years) exhibiting true Class III dental and skeletal malocclusions that were treated orthodontically with edgewise appliance and extractions of mandibular first premolars together with simultaneous anterior expansion of the maxillary arch. A retrospective cephalometric study was undertaken by Dr Kenneth Lew to determine the SOFT tissue changes at least 6 months postretention. Significant cephalometric changes included decrease in the mandibular incisor protrusiveness by 6.4mm(P<.001), and accompanying lower lip protrusiveness by 4.4mm (P<.01), together with a slight forward movement of the maxillary incisors by 1.7mm ( P<.05) and decrease in nasolabial angle (P<.05). Thus, Dr Kenneth Lew shows that the overall improvement in lip profile provided by this mandibular arch contraction/maxillary arch expansion orthodontic approach apeears to be a viable alternative when treating his patients who have a mild-to-moderate Class III and decline orthognathic surgery.
By nature observant of his patients’ concerns, Dr Kenneth Lew observes that when facial profiles are ranked among Asians to determine facial profile preference, the ranking in descending order of attractiveness is as follows:
Orthognathic profile, then bimaxillary retrusive profile, followed by bimaxillary protrusive profile, then mandibular retrognathic profile, and lastly, the least favoured mandibular prognathic profile (13). With this, Dr Kenneth Lew has an enhanced understanding of what an Asian patient considers as a ‘good’ and ‘bad’ facial profile, and tailors his patients’ orthodontic diagnosis and treatment planning with this in mind. Dr Kenneth Lew also hopes that publishing these articles will assist in assuaging the clinicians’ appetite for more knowledge.
Lew and Tay’s Study of Submentovertex (SMV) Cephalometric Norms in Chinese
In his academic career lecturing in the National University of Singapore, Dr Kenneth Lew , together with his colleague, studied the SMV cephalograms of a ramdon sample of 32 male Chinese subjects who were free from temporomandibular joint symptoms. The two gentlemen have developed a SMV cephalometric analysis comprising 5 angular measurements and 10 linear parameters to establish the SMV norms in Chinese adult population for clinical usage.
This is is seminal piece of research which provides clinicians with relevant information for the treatment of dentofacial orthopaedics in the diagnosis of mandibular asymmetry. The gentlemen established two NEW dento-anatomical points, the “Mei” and “L” points (the “Mei” point being named after Dr Kenneth Lew’s wife). When measured, and these 2 new points are found to be too close, this would indicate that the patient’s lower jaw may be assymetrical, and the human upper jaw is not movable (14).
Dr Kenneth Lew et al’s discovery of the “Mei” and “L” points was selected to be published in the international, peer reviewed academic journal, The American Journal of Orthodontics & Dentofacial Orthopaedics. Dr Kenneth Lew’s article is cited by 25 other international research papers, and is used to establish the SMV norms of Turkish adults (15).
In 1994, Dr Kenneth Lew establishes his private practice, TANGLIN DENTAL SURGEONS INVISIBLE BRACES CENTER. He treats his patients on a full time basis, imbued with his research knowledge. Dr Kenneth Lew set up his eponymous Advanced Dentist Training Center where he continues share his orthodontic knowledge by teaching and mentoring dentists in Asia via his modular Orthodontic courses conducted in Singapore, Thailand, Hong Kong and Indonesia.
Dr Kenneth Lew hopes by his research which is summarized here will help dentists and the lay public understand the intricacies and granularities of the world he lives in and enjoys – that of Dentistry and Orthodontics. He also hopes that his dental research will be continue to be built upon and remain useful in this fast changing world.
Some of Dr Kenneth Lew’s articles cited are here:
- published in the Australian Orthodontic Journal 1986;9-36, web4library.adelaide.edu.au/theses/09DM/09dm1669.pdf
- published in the Journal of Nihon University School of Dentistry (Japan) 1987;29:262-268 (Japan) 1987;29:262-268
- published in the American Journal of Orthodontics and Oral Surgery, 1989
- Microvascular changes in the rat molar periodontal ligament incident to orthodontic tooth extrusion with special reference to fenestrae, report submitted in partial fulfilment of the requirements for the Master of Dental Surgery, by Dr Kenneth Lew, BDS, Dept of Dentistry, University of Adelaide, South Australia
- Per the late Professor Dr Milton Sims, University of Adelaide.
- Holdaway, RA, A soft tissue cephalometric analysis and its use in orthodontic planning. Part 1, Am J Orthod 1983; 84;1-28
- Soft-tissue cephalometric norms in Chinese adults with esthethic facial profiles by Kenneth KK Lew e al, Journal of Oral & Maxillofacial Surgery, November 1992, vol 50 (11):1184-1189, cited by 45
- Comparison of white and Chinese perception of esthetic lip position by Hui Theng Cheong et al, The Angle Orthodontist, ol 84; Issue 2; Pages 246-253 ( volume publication date March 2014)
- Soft-tissue norms for Mahabubnagar population of Southern India, Journal of Clinical and Diagnostic Research (serial online) 2014, cited 2014, July 22: 255-259
- Cephalometric ideals in Chinese, Malay and Indian ethnic groups by KKK Lew, Asian J Aesthetic Dentistry, 1994; 2;35-38
- Cephalometric evaluation for Malaysian Malays by Steiner analysis, Mohammed HA et al, Scientific Research and Essays vol 6(3), pp 627-623, 4 Feb 2011
- Soft tissue profile changes following orthodontic treatment of Chinese adults with Class III malocclusion by KKK Lew, The International Journal of Adult Orthodontics and Orthognathic Surgery, Volume 5, number 1, 1990
- Ranking of facial profiles among Asians by KKK Lew et al, Journal of Esthetic Dentistry, vol 4, numbe4 4, July.Aug 1992, subsequently cited by 20 related research articles, onlinelibrary.wiley.com Vol 4 Issue 4, scholarbank.nus.edu.sg>DENTISTRY>PREVENTIVE DENTISTRY
- Submentovertex cephalometric norms in male Chinese adults by KKK Lew and Tay, American Journal of Orthodontics and Dentofacial Orthopaedics, USA 1993; 103:247-52, cited by 25.
- Submentovertex cepahlometric norms in Turkish adults by T Uysal et al, American Journal of Orthodontics and Dentofacial Orthopaedics December 2005; vol 128(6); 724-730.
- Dr Kenneth Lew Advanced Dentist Training Center, www.tanglindentalsurgeons.com
- Faceworks, Cover Story, The Straits times, Singapore, December 23, 1991.
- The Southern Light, Adelaide University Alumni Association